[v3] media: i2c: Add ar0234 camera sensor driver

  The driver is implemented with V4L2 framework,
and supports following features:

    - manual exposure and analog/digital gain control
    - vblank/hblank control
    - vflip/hflip control
    - runtime PM support
    - 1280x960 at 30FPS

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
---
v2 --> v3:
    - remove unused reg setting
    - add vflip/hflip control
    - add external clock check & lanes check

---
 drivers/media/i2c/Kconfig  |   11 +
 drivers/media/i2c/Makefile |    1 +
 drivers/media/i2c/ar0234.c | 1077 ++++++++++++++++++++++++++++++++++++
 3 files changed, 1089 insertions(+)
 create mode 100644 drivers/media/i2c/ar0234.c
  

Hi Dongcheng,

Thank you for the patch.

On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> The driver is implemented with V4L2 framework,
> and supports following features:
> 
>     - manual exposure and analog/digital gain control
>     - vblank/hblank control
>     - vflip/hflip control
>     - runtime PM support
>     - 1280x960 at 30FPS
> 
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> ---
> v2 --> v3:
>     - remove unused reg setting
>     - add vflip/hflip control
>     - add external clock check & lanes check
> 
> ---
>  drivers/media/i2c/Kconfig  |   11 +
>  drivers/media/i2c/Makefile |    1 +
>  drivers/media/i2c/ar0234.c | 1077 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 1089 insertions(+)
>  create mode 100644 drivers/media/i2c/ar0234.c
> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index c6d3ee472d81..7108d194c975 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called alvium-csi2.
>  
> +config VIDEO_AR0234
> +        tristate "ON Semiconductor AR0234 sensor support"
> +        depends on ACPI || COMPILE_TEST
> +        select V4L2_CCI_I2C
> +        help
> +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> +          AR0234 camera.
> +
> +          To compile this driver as a module, choose M here: the
> +          module will be called ar0234.
> +
>  config VIDEO_AR0521
>  	tristate "ON Semiconductor AR0521 sensor support"
>  	help
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index dfbe6448b549..57b4f62106d9 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
>  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
>  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
>  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
>  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
>  obj-$(CONFIG_VIDEO_BT819) += bt819.o
>  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> new file mode 100644
> index 000000000000..80fe5ffd1c64
> --- /dev/null
> +++ b/drivers/media/i2c/ar0234.c
> @@ -0,0 +1,1077 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2019 - 2024 Intel Corporation.
> +
> +#include <linux/acpi.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <asm/unaligned.h>
> +
> +#include <media/v4l2-cci.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +
> +/* Chip ID */
> +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> +#define AR0234_CHIP_ID			0x0a56
> +
> +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> +
> +#define AR0234_EXPOSURE_MIN		0
> +#define AR0234_EXPOSURE_MAX_MARGIN	80
> +#define AR0234_EXPOSURE_STEP		1
> +
> +#define AR0234_ANALOG_GAIN_MIN		0
> +#define AR0234_ANALOG_GAIN_MAX		0x7f
> +#define AR0234_ANALOG_GAIN_STEP		1
> +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> +
> +#define AR0234_GLOBAL_GAIN_MIN		0
> +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> +#define AR0234_GLOBAL_GAIN_STEP		1
> +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> +
> +#define AR0234_NATIVE_WIDTH		1920
> +#define AR0234_NATIVE_HEIGHT		1080
> +#define AR0234_COMMON_WIDTH		1280
> +#define AR0234_COMMON_HEIGHT		960
> +#define AR0234_PIXEL_ARRAY_LEFT		320
> +#define AR0234_PIXEL_ARRAY_TOP		60
> +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> +
> +#define AR0234_VTS_DEFAULT		0x04c4
> +#define AR0234_VTS_MAX			0xffff
> +#define AR0234_HTS_DEFAULT		0x04c4
> +#define AR0234_PPL_DEFAULT		3498
> +
> +#define AR0234_MODE_RESET		0x00d9
> +#define AR0234_MODE_STANDBY		0x2058
> +#define AR0234_MODE_STREAMING		0x205c
> +
> +#define AR0234_PIXEL_RATE		128000000ULL
> +#define AR0234_XCLK_FREQ		19200000ULL
> +
> +#define AR0234_TEST_PATTERN_DISABLE	0
> +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> +#define AR0234_TEST_PATTERN_WALKING	256
> +
> +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> +
> +struct ar0234_reg_list {
> +	u32 num_of_regs;
> +	const struct cci_reg_sequence *regs;
> +};
> +
> +struct ar0234_mode {
> +	u32 width;
> +	u32 height;
> +	u32 hts;
> +	u32 vts_def;
> +	u32 code;
> +	/* Sensor register settings for this mode */
> +	const struct ar0234_reg_list reg_list;
> +};
> +
> +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> +	{ CCI_REG16(0x3f4c), 0x121f },
> +	{ CCI_REG16(0x3f4e), 0x121f },
> +	{ CCI_REG16(0x3f50), 0x0b81 },
> +	{ CCI_REG16(0x31e0), 0x0003 },
> +	{ CCI_REG16(0x30b0), 0x0028 },
> +	/* R0x3088 specify the sequencer RAM access address. */
> +	{ CCI_REG16(0x3088), 0x8000 },
> +	/* R0x3086 write the sequencer RAM. */
> +	{ CCI_REG16(0x3086), 0xc1ae },
> +	{ CCI_REG16(0x3086), 0x327f },
> +	{ CCI_REG16(0x3086), 0x5780 },
> +	{ CCI_REG16(0x3086), 0x272f },
> +	{ CCI_REG16(0x3086), 0x7416 },

Storing the sequencer data in this table wastes lots of memory and CPU
cycles. Please move the data out to a

static const u16 ar0234_sequencer[] = {
	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
	...
};

table, and program it with

	/* Program the sequencer. */
	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
		cci_write(ar0234->regmap, CCI_REG16(0x3086),
			  ar0234_sequencer[i], &ret);

And please define macros for the sequencer access registers 0x3086 and
0x3088, as well as for the bits of the 0x3088 register.

[snip]

> +	{ CCI_REG16(0x302a), 0x0005 },
> +	{ CCI_REG16(0x302c), 0x0001 },
> +	{ CCI_REG16(0x302e), 0x0003 },
> +	{ CCI_REG16(0x3030), 0x0032 },
> +	{ CCI_REG16(0x3036), 0x000a },
> +	{ CCI_REG16(0x3038), 0x0001 },
> +	{ CCI_REG16(0x30b0), 0x0028 },
> +	{ CCI_REG16(0x31b0), 0x0082 },
> +	{ CCI_REG16(0x31b2), 0x005c },
> +	{ CCI_REG16(0x31b4), 0x5248 },
> +	{ CCI_REG16(0x31b6), 0x3257 },
> +	{ CCI_REG16(0x31b8), 0x904b },
> +	{ CCI_REG16(0x31ba), 0x030b },
> +	{ CCI_REG16(0x31bc), 0x8e09 },
> +	{ CCI_REG16(0x3354), 0x002b },
> +	{ CCI_REG16(0x31d0), 0x0000 },
> +	{ CCI_REG16(0x31ae), 0x0204 },
> +	{ CCI_REG16(0x3002), 0x0080 },
> +	{ CCI_REG16(0x3004), 0x0148 },
> +	{ CCI_REG16(0x3006), 0x043f },
> +	{ CCI_REG16(0x3008), 0x0647 },
> +	{ CCI_REG16(0x3064), 0x1802 },
> +	{ CCI_REG16(0x300a), 0x04c4 },
> +	{ CCI_REG16(0x300c), 0x04c4 },
> +	{ CCI_REG16(0x30a2), 0x0001 },
> +	{ CCI_REG16(0x30a6), 0x0001 },
> +	{ CCI_REG16(0x3012), 0x010c },
> +	{ CCI_REG16(0x3786), 0x0006 },
> +	{ CCI_REG16(0x31ae), 0x0202 },
> +	{ CCI_REG16(0x3088), 0x8050 },
> +	{ CCI_REG16(0x3086), 0x9237 },

This can stay here if it needs to be programmed separately from the rest
of the sequencer data, but please use macros to replace the
hardcoded register addresses, and the value of the 0x3088 register.


> +	{ CCI_REG16(0x3044), 0x0410 },
> +	{ CCI_REG16(0x3094), 0x03d4 },
> +	{ CCI_REG16(0x3096), 0x0280 },
> +	{ CCI_REG16(0x30ba), 0x7606 },
> +	{ CCI_REG16(0x30b0), 0x0028 },
> +	{ CCI_REG16(0x30ba), 0x7600 },
> +	{ CCI_REG16(0x30fe), 0x002a },
> +	{ CCI_REG16(0x31de), 0x0410 },
> +	{ CCI_REG16(0x3ed6), 0x1435 },
> +	{ CCI_REG16(0x3ed8), 0x9865 },
> +	{ CCI_REG16(0x3eda), 0x7698 },
> +	{ CCI_REG16(0x3edc), 0x99ff },
> +	{ CCI_REG16(0x3ee2), 0xbb88 },
> +	{ CCI_REG16(0x3ee4), 0x8836 },
> +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> +	{ CCI_REG16(0x3ef2), 0x0000 },
> +	{ CCI_REG16(0x3ef8), 0x6166 },
> +	{ CCI_REG16(0x3efa), 0x3333 },
> +	{ CCI_REG16(0x3efc), 0x6634 },
> +	{ CCI_REG16(0x3088), 0x81ba },
> +	{ CCI_REG16(0x3086), 0x3d02 },

Same here.

> +	{ CCI_REG16(0x3276), 0x05dc },
> +	{ CCI_REG16(0x3f00), 0x9d05 },
> +	{ CCI_REG16(0x3ed2), 0xfa86 },
> +	{ CCI_REG16(0x3eee), 0xa4fe },
> +	{ CCI_REG16(0x3ecc), 0x6e42 },
> +	{ CCI_REG16(0x3ecc), 0x0e42 },
> +	{ CCI_REG16(0x3eec), 0x0c0c },
> +	{ CCI_REG16(0x3ee8), 0xaae4 },
> +	{ CCI_REG16(0x3ee6), 0x3363 },
> +	{ CCI_REG16(0x3ee6), 0x3363 },
> +	{ CCI_REG16(0x3ee8), 0xaae4 },
> +	{ CCI_REG16(0x3ee8), 0xaae4 },
> +	{ CCI_REG16(0x3180), 0xc24f },
> +	{ CCI_REG16(0x3102), 0x5000 },
> +	{ CCI_REG16(0x3060), 0x000d },
> +	{ CCI_REG16(0x3ed0), 0xff44 },
> +	{ CCI_REG16(0x3ed2), 0xaa86 },
> +	{ CCI_REG16(0x3ed4), 0x031f },
> +	{ CCI_REG16(0x3eee), 0xa4aa },

Among all the registers above, at least the following need a macro for
the register name and register bits:

0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a,
0x302c, 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2,
0x30a6, 0x30b0, 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2,
0x31b4, 0x31b6, 0x31b8, 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
0x3786

Some of them should also be handled programmatically, not hardcoded.

Ideally, the following registers should also be documented with macros:

0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276

0x30ba, in particular, varies depending on the analog gain and pixel
clock, so it needs to be handled programmatically.

> +};
> +
> +static const char * const ar0234_test_pattern_menu[] = {
> +	"Disabled",
> +	"Color Bars",
> +	"Solid Color",
> +	"Grey Color Bars",
> +	"Walking 1s",
> +};
> +
> +static const int ar0234_test_pattern_val[] = {
> +	AR0234_TEST_PATTERN_DISABLE,
> +	AR0234_TEST_PATTERN_COLOR_BARS,
> +	AR0234_TEST_PATTERN_SOLID_COLOR,
> +	AR0234_TEST_PATTERN_GREY_COLOR,
> +	AR0234_TEST_PATTERN_WALKING,
> +};
> +
> +static const s64 link_freq_menu_items[] = {
> +	360000000ULL,
> +};
> +
> +static const struct ar0234_mode supported_modes[] = {
> +	{
> +		.width = AR0234_COMMON_WIDTH,
> +		.height = AR0234_COMMON_HEIGHT,
> +		.hts = AR0234_HTS_DEFAULT,
> +		.vts_def = AR0234_VTS_DEFAULT,
> +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> +		.reg_list = {
> +			.num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> +			.regs = mode_1280x960_10bit_2lane,
> +		},
> +	},
> +};
> +
> +struct ar0234 {
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +	struct v4l2_ctrl_handler ctrl_handler;
> +
> +	/* V4L2 Controls */
> +	struct v4l2_ctrl *link_freq;
> +	struct v4l2_ctrl *exposure;
> +	struct v4l2_ctrl *hblank;
> +	struct v4l2_ctrl *vblank;
> +	struct v4l2_ctrl *vflip;
> +	struct v4l2_ctrl *hflip;
> +	struct regmap *regmap;
> +	unsigned long link_freq_bitmap;
> +	const struct ar0234_mode *cur_mode;
> +};
> +
> +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct ar0234 *ar0234 =
> +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +	s64 exposure_max, exposure_def;
> +	struct v4l2_subdev_state *state;
> +	const struct v4l2_mbus_framefmt *format;
> +	int ret;
> +
> +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> +	format = v4l2_subdev_state_get_format(state, 0);
> +
> +	/* Propagate change of current control to all related controls */
> +	if (ctrl->id == V4L2_CID_VBLANK) {
> +		/* Update max exposure while meeting expected vblanking */
> +		exposure_max = format->height + ctrl->val -
> +			       AR0234_EXPOSURE_MAX_MARGIN;
> +		exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> +		__v4l2_ctrl_modify_range(ar0234->exposure,
> +					 ar0234->exposure->minimum,
> +					 exposure_max, ar0234->exposure->step,
> +					 exposure_def);
> +	}
> +
> +	/* V4L2 controls values will be applied only when power is already up */
> +	if (!pm_runtime_get_if_in_use(&client->dev))
> +		return 0;
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_ANALOGUE_GAIN:
> +		ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> +				ctrl->val, NULL);
> +		break;
> +
> +	case V4L2_CID_DIGITAL_GAIN:
> +		ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> +				ctrl->val, NULL);
> +		break;
> +
> +	case V4L2_CID_EXPOSURE:
> +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> +				ctrl->val, NULL);
> +		break;
> +
> +	case V4L2_CID_VBLANK:
> +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> +				ar0234->cur_mode->height + ctrl->val, NULL);
> +		break;
> +
> +	case V4L2_CID_HFLIP:
> +	case V4L2_CID_VFLIP:
> +		u64 reg;
> +
> +		ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> +			       &reg, NULL);
> +		if (ret)
> +			break;
> +
> +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> +			 AR0234_ORIENTATION_VFLIP);
> +		if (ar0234->hflip->val)
> +			reg |= AR0234_ORIENTATION_HFLIP;
> +		if (ar0234->vflip->val)
> +			reg |= AR0234_ORIENTATION_VFLIP;
> +
> +		ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> +				reg, NULL);
> +		break;
> +
> +	case V4L2_CID_TEST_PATTERN:
> +		ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> +				ar0234_test_pattern_val[ctrl->val], NULL);
> +		break;
> +
> +	default:
> +		ret = -EINVAL;
> +		break;
> +	}
> +
> +	pm_runtime_put(&client->dev);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> +	.s_ctrl = ar0234_set_ctrl,
> +};
> +
> +static int ar0234_init_controls(struct ar0234 *ar0234)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +	struct v4l2_fwnode_device_properties props;
> +	struct v4l2_ctrl_handler *ctrl_hdlr;
> +	s64 exposure_max, vblank_max, vblank_def, hblank;
> +	u32 link_freq_size;
> +	int ret;
> +
> +	ctrl_hdlr = &ar0234->ctrl_handler;
> +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> +	if (ret)
> +		return ret;
> +
> +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> +						   &ar0234_ctrl_ops,
> +						   V4L2_CID_LINK_FREQ,
> +						   link_freq_size, 0,
> +						   link_freq_menu_items);
> +	if (ar0234->link_freq)
> +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
> +			  AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> +			  AR0234_ANALOG_GAIN_STEP, AR0234_ANALOG_GAIN_DEFAULT);
> +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> +			  AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> +			  AR0234_GLOBAL_GAIN_STEP, AR0234_GLOBAL_GAIN_DEFAULT);
> +
> +	exposure_max = ar0234->cur_mode->vts_def - AR0234_EXPOSURE_MAX_MARGIN;
> +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> +					     V4L2_CID_EXPOSURE,
> +					     AR0234_EXPOSURE_MIN, exposure_max,
> +					     AR0234_EXPOSURE_STEP,
> +					     exposure_max);
> +
> +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> +			  AR0234_PIXEL_RATE);
> +
> +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> +	vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> +					   vblank_def);
> +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> +					   hblank);
> +	if (ar0234->hblank)
> +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> +
> +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> +				     V4L2_CID_TEST_PATTERN,
> +				     ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> +				     0, 0, ar0234_test_pattern_menu);
> +
> +	if (ctrl_hdlr->error)
> +		return ctrl_hdlr->error;
> +
> +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> +					      &props);
> +	if (ret)
> +		return ret;
> +
> +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> +
> +	return 0;
> +}
> +
> +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> +				     struct v4l2_mbus_framefmt *fmt)
> +{
> +	fmt->width = mode->width;
> +	fmt->height = mode->height;
> +	fmt->code = mode->code;
> +	fmt->field = V4L2_FIELD_NONE;
> +}
> +
> +static int ar0234_start_streaming(struct ar0234 *ar0234)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +	const struct ar0234_reg_list *reg_list;
> +	int ret;
> +
> +	ret = pm_runtime_resume_and_get(&client->dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> +	 * the frame being generated will be truncated.
> +	 */
> +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> +			AR0234_MODE_RESET, NULL);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to reset");
> +		goto err_rpm_put;
> +	}
> +
> +	usleep_range(1000, 1500);
> +
> +	reg_list = &ar0234->cur_mode->reg_list;
> +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> +				  reg_list->num_of_regs, NULL);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to set mode");
> +		goto err_rpm_put;
> +	}
> +
> +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> +	if (ret)
> +		goto err_rpm_put;
> +
> +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> +			AR0234_MODE_STREAMING, NULL);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to start stream");
> +		goto err_rpm_put;
> +	}
> +
> +	return 0;
> +
> +err_rpm_put:
> +	pm_runtime_put(&client->dev);
> +	return ret;
> +}
> +
> +static int ar0234_stop_streaming(struct ar0234 *ar0234)
> +{
> +	int ret;
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +
> +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> +			AR0234_MODE_STANDBY, NULL);
> +	if (ret < 0)
> +		dev_err(&client->dev, "failed to stop stream");
> +
> +	pm_runtime_put(&client->dev);
> +	return ret;
> +}
> +
> +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct ar0234 *ar0234 = to_ar0234(sd);
> +	struct v4l2_subdev_state *state;
> +	int ret = 0;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +	if (enable)
> +		ret = ar0234_start_streaming(ar0234);
> +	else
> +		ret = ar0234_stop_streaming(ar0234);
> +
> +	/* vflip and hflip cannot change during streaming */
> +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> +	v4l2_subdev_unlock_state(state);
> +
> +	return ret;
> +}
> +
> +static int ar0234_set_format(struct v4l2_subdev *sd,
> +			     struct v4l2_subdev_state *sd_state,
> +			     struct v4l2_subdev_format *fmt)
> +{
> +	struct ar0234 *ar0234 = to_ar0234(sd);
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +	struct v4l2_rect *crop;
> +	const struct ar0234_mode *mode;
> +	s64 hblank;
> +	int ret;
> +
> +	mode = v4l2_find_nearest_size(supported_modes,
> +				      ARRAY_SIZE(supported_modes),
> +				      width, height,
> +				      fmt->format.width,
> +				      fmt->format.height);
> +
> +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> +	crop->width = mode->width;
> +	crop->height = mode->height;
> +
> +	ar0234_update_pad_format(mode, &fmt->format);
> +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> +
> +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> +		return 0;
> +
> +	ar0234->cur_mode = mode;
> +
> +	hblank = AR0234_PPL_DEFAULT - mode->width;
> +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> +				       1, hblank);
> +	if (ret) {
> +		dev_err(&client->dev, "HB ctrl range update failed");
> +		return ret;
> +	}
> +
> +	/* Update limits and set FPS to default */
> +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> +				       AR0234_VTS_MAX - mode->height, 1,
> +				       mode->vts_def - mode->height);
> +	if (ret) {
> +		dev_err(&client->dev, "VB ctrl range update failed");
> +		return ret;
> +	}
> +
> +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> +	if (ret) {
> +		dev_err(&client->dev, "VB ctrl set failed");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *sd_state,
> +				 struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	if (code->index > 0)
> +		return -EINVAL;
> +
> +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> +
> +	return 0;
> +}
> +
> +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> +				  struct v4l2_subdev_state *sd_state,
> +				  struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	if (fse->index >= ARRAY_SIZE(supported_modes))
> +		return -EINVAL;
> +
> +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> +		return -EINVAL;
> +
> +	fse->min_width = supported_modes[fse->index].width;
> +	fse->max_width = fse->min_width;
> +	fse->min_height = supported_modes[fse->index].height;
> +	fse->max_height = fse->min_height;
> +
> +	return 0;
> +}
> +
> +static int ar0234_get_selection(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *state,
> +				struct v4l2_subdev_selection *sel)
> +{
> +	switch (sel->target) {
> +	case V4L2_SEL_TGT_CROP_DEFAULT:
> +	case V4L2_SEL_TGT_CROP_BOUNDS:
> +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> +		sel->r.width = AR0234_COMMON_WIDTH;
> +		sel->r.height = AR0234_COMMON_HEIGHT;
> +		break;
> +
> +	case V4L2_SEL_TGT_CROP:
> +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> +		break;
> +
> +	case V4L2_SEL_TGT_NATIVE_SIZE:
> +		sel->r.top = 0;
> +		sel->r.left = 0;
> +		sel->r.width = AR0234_NATIVE_WIDTH;
> +		sel->r.height = AR0234_NATIVE_HEIGHT;
> +		break;
> +
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ar0234_init_state(struct v4l2_subdev *sd,
> +			     struct v4l2_subdev_state *sd_state)
> +{
> +	struct v4l2_subdev_format fmt = {
> +		.which = V4L2_SUBDEV_FORMAT_TRY,
> +		.pad = 0,
> +		.format = {
> +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> +			.width = AR0234_COMMON_WIDTH,
> +			.height = AR0234_COMMON_HEIGHT,
> +		},
> +	};
> +
> +	ar0234_set_format(sd, sd_state, &fmt);
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> +	.s_stream = ar0234_set_stream,
> +};
> +
> +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> +	.set_fmt = ar0234_set_format,
> +	.get_fmt = v4l2_subdev_get_fmt,
> +	.enum_mbus_code = ar0234_enum_mbus_code,
> +	.enum_frame_size = ar0234_enum_frame_size,
> +	.get_selection = ar0234_get_selection,
> +};
> +
> +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> +	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
> +};
> +
> +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> +	.core = &ar0234_core_ops,
> +	.video = &ar0234_video_ops,
> +	.pad = &ar0234_pad_ops,
> +};
> +
> +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> +	.init_state = ar0234_init_state,
> +};
> +
> +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct device *dev)
> +{
> +	struct fwnode_handle *endpoint;
> +	struct v4l2_fwnode_endpoint bus_cfg = {
> +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> +	};
> +	int ret;
> +
> +	endpoint =
> +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> +						FWNODE_GRAPH_ENDPOINT_NEXT);
> +	if (!endpoint) {
> +		dev_err(dev, "endpoint node not found");
> +		return -EPROBE_DEFER;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> +	if (ret) {
> +		dev_err(dev, "parsing endpoint node failed");
> +		goto out_err;
> +	}
> +
> +	/* Check the number of MIPI CSI2 data lanes */
> +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> +		dev_err(dev, "only 2 or 4 data lanes are currently supported");
> +		goto out_err;
> +	}
> +
> +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> +				       bus_cfg.nr_of_link_frequencies,
> +				       link_freq_menu_items,
> +				       ARRAY_SIZE(link_freq_menu_items),
> +				       &ar0234->link_freq_bitmap);
> +	if (ret)
> +		goto out_err;
> +
> +out_err:
> +	v4l2_fwnode_endpoint_free(&bus_cfg);
> +	fwnode_handle_put(endpoint);
> +	return ret;
> +}
> +
> +static int ar0234_identify_module(struct ar0234 *ar0234)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> +	int ret;
> +	u64 val;
> +
> +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> +	if (ret)
> +		return ret;
> +
> +	if (val != AR0234_CHIP_ID) {
> +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> +			AR0234_CHIP_ID, val);
> +		return -ENXIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static void ar0234_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct ar0234 *ar0234 = to_ar0234(sd);
> +
> +	v4l2_async_unregister_subdev(&ar0234->sd);
> +	v4l2_subdev_cleanup(sd);
> +	media_entity_cleanup(&ar0234->sd.entity);
> +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> +	pm_runtime_disable(&client->dev);
> +	pm_runtime_set_suspended(&client->dev);
> +}
> +
> +static int ar0234_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct ar0234 *ar0234;
> +	struct clk *xclk;
> +	u32 xclk_freq;
> +	int ret;
> +
> +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> +	if (!ar0234)
> +		return -ENOMEM;
> +
> +	ret = ar0234_parse_fwnode(ar0234, dev);
> +	if (ret)
> +		return ret;
> +
> +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> +	if (IS_ERR(ar0234->regmap))
> +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> +				     "failed to init CCI");
> +
> +	v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> +
> +	xclk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(xclk)) {
> +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> +		return PTR_ERR(xclk);
> +	}
> +
> +	xclk_freq = clk_get_rate(xclk);
> +	if (xclk_freq != AR0234_XCLK_FREQ) {
> +		dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> +		return -EINVAL;
> +	}
> +
> +	/* Check module identity */
> +	ret = ar0234_identify_module(ar0234);
> +	if (ret) {
> +		dev_err(dev, "failed to find sensor: %d", ret);
> +		return ret;
> +	}
> +
> +	ar0234->cur_mode = &supported_modes[0];
> +	ret = ar0234_init_controls(ar0234);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to init controls: %d", ret);
> +		goto probe_error_v4l2_ctrl_handler_free;
> +	}
> +
> +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +
> +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> +	ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> +		goto probe_error_v4l2_ctrl_handler_free;
> +	}
> +
> +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> +	if (ret < 0) {
> +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> +		goto probe_error_media_entity_cleanup;
> +	}
> +
> +	/*
> +	 * Device is already turned on by i2c-core with ACPI domain PM.
> +	 * Enable runtime PM and turn off the device.
> +	 */
> +	pm_runtime_set_active(&client->dev);
> +	pm_runtime_enable(&client->dev);
> +	pm_runtime_idle(&client->dev);
> +
> +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> +			ret);
> +		goto probe_error_rpm;
> +	}
> +
> +	return 0;
> +probe_error_rpm:
> +	pm_runtime_disable(&client->dev);
> +	v4l2_subdev_cleanup(&ar0234->sd);
> +
> +probe_error_media_entity_cleanup:
> +	media_entity_cleanup(&ar0234->sd.entity);
> +
> +probe_error_v4l2_ctrl_handler_free:
> +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> +
> +	return ret;
> +}
> +
> +static const struct acpi_device_id ar0234_acpi_ids[] = {
> +	{ "INTC10C0" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> +
> +static struct i2c_driver ar0234_i2c_driver = {
> +	.driver = {
> +		.name = "ar0234",
> +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> +	},
> +	.probe = ar0234_probe,
> +	.remove = ar0234_remove,
> +};
> +
> +module_i2c_driver(ar0234_i2c_driver);
> +
> +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> +MODULE_LICENSE("GPL");
  

Hi Dongcheng,

kernel test robot noticed the following build errors:

[auto build test ERROR on media-tree/master]
[also build test ERROR on sailus-media-tree/master linuxtv-media-stage/master linus/master v6.10-rc4 next-20240617]
[cannot apply to sailus-media-tree/streams]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Dongcheng-Yan/media-i2c-Add-ar0234-camera-sensor-driver/20240614-161208
base:   git://linuxtv.org/media_tree.git master
patch link:    https://lore.kernel.org/r/20240614080941.3938212-1-dongcheng.yan%40intel.com
patch subject: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
config: powerpc64-randconfig-r064-20240618 (https://download.01.org/0day-ci/archive/20240618/202406180807.dvu7E34U-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240618/202406180807.dvu7E34U-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202406180807.dvu7E34U-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/media/i2c/ar0234.c:508:3: error: expected expression
                   u64 reg;
                   ^
>> drivers/media/i2c/ar0234.c:511:12: error: use of undeclared identifier 'reg'; did you mean 'ret'?
                                  &reg, NULL);
                                   ^~~
                                   ret
   drivers/media/i2c/ar0234.c:464:6: note: 'ret' declared here
           int ret;
               ^
   drivers/media/i2c/ar0234.c:515:3: error: use of undeclared identifier 'reg'; did you mean 'ret'?
                   reg &= ~(AR0234_ORIENTATION_HFLIP |
                   ^~~
                   ret
   drivers/media/i2c/ar0234.c:464:6: note: 'ret' declared here
           int ret;
               ^
   drivers/media/i2c/ar0234.c:518:4: error: use of undeclared identifier 'reg'; did you mean 'ret'?
                           reg |= AR0234_ORIENTATION_HFLIP;
                           ^~~
                           ret
   drivers/media/i2c/ar0234.c:464:6: note: 'ret' declared here
           int ret;
               ^
   drivers/media/i2c/ar0234.c:520:4: error: use of undeclared identifier 'reg'; did you mean 'ret'?
                           reg |= AR0234_ORIENTATION_VFLIP;
                           ^~~
                           ret
   drivers/media/i2c/ar0234.c:464:6: note: 'ret' declared here
           int ret;
               ^
   drivers/media/i2c/ar0234.c:523:5: error: use of undeclared identifier 'reg'; did you mean 'ret'?
                                   reg, NULL);
                                   ^~~
                                   ret
   drivers/media/i2c/ar0234.c:464:6: note: 'ret' declared here
           int ret;
               ^
   6 errors generated.


vim +508 drivers/media/i2c/ar0234.c

   455	
   456	static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl)
   457	{
   458		struct ar0234 *ar0234 =
   459			container_of(ctrl->handler, struct ar0234, ctrl_handler);
   460		struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
   461		s64 exposure_max, exposure_def;
   462		struct v4l2_subdev_state *state;
   463		const struct v4l2_mbus_framefmt *format;
   464		int ret;
   465	
   466		state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
   467		format = v4l2_subdev_state_get_format(state, 0);
   468	
   469		/* Propagate change of current control to all related controls */
   470		if (ctrl->id == V4L2_CID_VBLANK) {
   471			/* Update max exposure while meeting expected vblanking */
   472			exposure_max = format->height + ctrl->val -
   473				       AR0234_EXPOSURE_MAX_MARGIN;
   474			exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
   475			__v4l2_ctrl_modify_range(ar0234->exposure,
   476						 ar0234->exposure->minimum,
   477						 exposure_max, ar0234->exposure->step,
   478						 exposure_def);
   479		}
   480	
   481		/* V4L2 controls values will be applied only when power is already up */
   482		if (!pm_runtime_get_if_in_use(&client->dev))
   483			return 0;
   484	
   485		switch (ctrl->id) {
   486		case V4L2_CID_ANALOGUE_GAIN:
   487			ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
   488					ctrl->val, NULL);
   489			break;
   490	
   491		case V4L2_CID_DIGITAL_GAIN:
   492			ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
   493					ctrl->val, NULL);
   494			break;
   495	
   496		case V4L2_CID_EXPOSURE:
   497			ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
   498					ctrl->val, NULL);
   499			break;
   500	
   501		case V4L2_CID_VBLANK:
   502			ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
   503					ar0234->cur_mode->height + ctrl->val, NULL);
   504			break;
   505	
   506		case V4L2_CID_HFLIP:
   507		case V4L2_CID_VFLIP:
 > 508			u64 reg;
   509	
   510			ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
 > 511				       &reg, NULL);
   512			if (ret)
   513				break;
   514	
   515			reg &= ~(AR0234_ORIENTATION_HFLIP |
   516				 AR0234_ORIENTATION_VFLIP);
   517			if (ar0234->hflip->val)
   518				reg |= AR0234_ORIENTATION_HFLIP;
   519			if (ar0234->vflip->val)
   520				reg |= AR0234_ORIENTATION_VFLIP;
   521	
   522			ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
   523					reg, NULL);
   524			break;
   525	
   526		case V4L2_CID_TEST_PATTERN:
   527			ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
   528					ar0234_test_pattern_val[ctrl->val], NULL);
   529			break;
   530	
   531		default:
   532			ret = -EINVAL;
   533			break;
   534		}
   535	
   536		pm_runtime_put(&client->dev);
   537	
   538		return ret;
   539	}
   540
  

Hi Larent,

Thanks for your review and meaningful suggestions. I have contacted the vendor and optimized the code related to the register settings.
The response is as follows:

> -----Original Message-----
> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: Friday, June 14, 2024 10:25 PM
> To: Yan, Dongcheng <dongcheng.yan@intel.com>
> Cc: sakari.ailus@linux.intel.com; linux-media@vger.kernel.org;
> tomi.valkeinen@ideasonboard.com; jacopo.mondi@ideasonboard.com;
> bingbu.cao@linux.intel.com; dave.stevenson@raspberrypi.com; Li, Daxing
> <daxing.li@intel.com>; Yao, Hao <hao.yao@intel.com>
> Subject: Re: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
> 
> Hi Dongcheng,
> 
> Thank you for the patch.
> 
> On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > The driver is implemented with V4L2 framework, and supports following
> > features:
> >
> >     - manual exposure and analog/digital gain control
> >     - vblank/hblank control
> >     - vflip/hflip control
> >     - runtime PM support
> >     - 1280x960 at 30FPS
> >
> > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > ---
> > v2 --> v3:
> >     - remove unused reg setting
> >     - add vflip/hflip control
> >     - add external clock check & lanes check
> >
> > ---
> >  drivers/media/i2c/Kconfig  |   11 +
> >  drivers/media/i2c/Makefile |    1 +
> >  drivers/media/i2c/ar0234.c | 1077
> > ++++++++++++++++++++++++++++++++++++
> >  3 files changed, 1089 insertions(+)
> >  create mode 100644 drivers/media/i2c/ar0234.c
> >
> > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > index c6d3ee472d81..7108d194c975 100644
> > --- a/drivers/media/i2c/Kconfig
> > +++ b/drivers/media/i2c/Kconfig
> > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> >  	  To compile this driver as a module, choose M here: the
> >  	  module will be called alvium-csi2.
> >
> > +config VIDEO_AR0234
> > +        tristate "ON Semiconductor AR0234 sensor support"
> > +        depends on ACPI || COMPILE_TEST
> > +        select V4L2_CCI_I2C
> > +        help
> > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > +          AR0234 camera.
> > +
> > +          To compile this driver as a module, choose M here: the
> > +          module will be called ar0234.
> > +
> >  config VIDEO_AR0521
> >  	tristate "ON Semiconductor AR0521 sensor support"
> >  	help
> > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > index dfbe6448b549..57b4f62106d9 100644
> > --- a/drivers/media/i2c/Makefile
> > +++ b/drivers/media/i2c/Makefile
> > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > new file mode 100644 index 000000000000..80fe5ffd1c64
> > --- /dev/null
> > +++ b/drivers/media/i2c/ar0234.c
> > @@ -0,0 +1,1077 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/pm_runtime.h>
> > +#include <asm/unaligned.h>
> > +
> > +#include <media/v4l2-cci.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +
> > +/* Chip ID */
> > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > +#define AR0234_CHIP_ID			0x0a56
> > +
> > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > +
> > +#define AR0234_EXPOSURE_MIN		0
> > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > +#define AR0234_EXPOSURE_STEP		1
> > +
> > +#define AR0234_ANALOG_GAIN_MIN		0
> > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > +#define AR0234_ANALOG_GAIN_STEP		1
> > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > +
> > +#define AR0234_GLOBAL_GAIN_MIN		0
> > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > +#define AR0234_GLOBAL_GAIN_STEP		1
> > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > +
> > +#define AR0234_NATIVE_WIDTH		1920
> > +#define AR0234_NATIVE_HEIGHT		1080
> > +#define AR0234_COMMON_WIDTH		1280
> > +#define AR0234_COMMON_HEIGHT		960
> > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > +#define AR0234_PIXEL_ARRAY_TOP		60
> > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > +
> > +#define AR0234_VTS_DEFAULT		0x04c4
> > +#define AR0234_VTS_MAX			0xffff
> > +#define AR0234_HTS_DEFAULT		0x04c4
> > +#define AR0234_PPL_DEFAULT		3498
> > +
> > +#define AR0234_MODE_RESET		0x00d9
> > +#define AR0234_MODE_STANDBY		0x2058
> > +#define AR0234_MODE_STREAMING		0x205c
> > +
> > +#define AR0234_PIXEL_RATE		128000000ULL
> > +#define AR0234_XCLK_FREQ		19200000ULL
> > +
> > +#define AR0234_TEST_PATTERN_DISABLE	0
> > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > +#define AR0234_TEST_PATTERN_WALKING	256
> > +
> > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > +
> > +struct ar0234_reg_list {
> > +	u32 num_of_regs;
> > +	const struct cci_reg_sequence *regs; };
> > +
> > +struct ar0234_mode {
> > +	u32 width;
> > +	u32 height;
> > +	u32 hts;
> > +	u32 vts_def;
> > +	u32 code;
> > +	/* Sensor register settings for this mode */
> > +	const struct ar0234_reg_list reg_list; };
> > +
> > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > +	{ CCI_REG16(0x3f4c), 0x121f },
> > +	{ CCI_REG16(0x3f4e), 0x121f },
> > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > +	{ CCI_REG16(0x31e0), 0x0003 },
> > +	{ CCI_REG16(0x30b0), 0x0028 },
> > +	/* R0x3088 specify the sequencer RAM access address. */
> > +	{ CCI_REG16(0x3088), 0x8000 },
> > +	/* R0x3086 write the sequencer RAM. */
> > +	{ CCI_REG16(0x3086), 0xc1ae },
> > +	{ CCI_REG16(0x3086), 0x327f },
> > +	{ CCI_REG16(0x3086), 0x5780 },
> > +	{ CCI_REG16(0x3086), 0x272f },
> > +	{ CCI_REG16(0x3086), 0x7416 },
> 
> Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> Please move the data out to a
> 
> static const u16 ar0234_sequencer[] = {
> 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> 	...
> };
> 
> table, and program it with
> 
> 	/* Program the sequencer. */
> 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> 			  ar0234_sequencer[i], &ret);
> 
> And please define macros for the sequencer access registers 0x3086 and
> 0x3088, as well as for the bits of the 0x3088 register.
> 
> [snip]
> 
[Yan, Dongcheng
  

Hello Dongcheng,

On Mon, Jul 01, 2024 at 05:22:22AM +0000, Yan, Dongcheng wrote:
> Hi Larent,
> 
> Thanks for your review and meaningful suggestions. I have contacted
> the vendor and optimized the code related to the register settings.
> The response is as follows:

I think you forgot the response below :-)

> > -----Original Message-----
> > From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Sent: Friday, June 14, 2024 10:25 PM
> > To: Yan, Dongcheng <dongcheng.yan@intel.com>
> > Cc: sakari.ailus@linux.intel.com; linux-media@vger.kernel.org;
> > tomi.valkeinen@ideasonboard.com; jacopo.mondi@ideasonboard.com;
> > bingbu.cao@linux.intel.com; dave.stevenson@raspberrypi.com; Li, Daxing
> > <daxing.li@intel.com>; Yao, Hao <hao.yao@intel.com>
> > Subject: Re: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
> > 
> > Hi Dongcheng,
> > 
> > Thank you for the patch.
> > 
> > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > The driver is implemented with V4L2 framework, and supports following
> > > features:
> > >
> > >     - manual exposure and analog/digital gain control
> > >     - vblank/hblank control
> > >     - vflip/hflip control
> > >     - runtime PM support
> > >     - 1280x960 at 30FPS
> > >
> > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > ---
> > > v2 --> v3:
> > >     - remove unused reg setting
> > >     - add vflip/hflip control
> > >     - add external clock check & lanes check
> > >
> > > ---
> > >  drivers/media/i2c/Kconfig  |   11 +
> > >  drivers/media/i2c/Makefile |    1 +
> > >  drivers/media/i2c/ar0234.c | 1077
> > > ++++++++++++++++++++++++++++++++++++
> > >  3 files changed, 1089 insertions(+)
> > >  create mode 100644 drivers/media/i2c/ar0234.c
> > >
> > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > index c6d3ee472d81..7108d194c975 100644
> > > --- a/drivers/media/i2c/Kconfig
> > > +++ b/drivers/media/i2c/Kconfig
> > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > >  	  To compile this driver as a module, choose M here: the
> > >  	  module will be called alvium-csi2.
> > >
> > > +config VIDEO_AR0234
> > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > +        depends on ACPI || COMPILE_TEST
> > > +        select V4L2_CCI_I2C
> > > +        help
> > > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > > +          AR0234 camera.
> > > +
> > > +          To compile this driver as a module, choose M here: the
> > > +          module will be called ar0234.
> > > +
> > >  config VIDEO_AR0521
> > >  	tristate "ON Semiconductor AR0521 sensor support"
> > >  	help
> > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > > index dfbe6448b549..57b4f62106d9 100644
> > > --- a/drivers/media/i2c/Makefile
> > > +++ b/drivers/media/i2c/Makefile
> > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > > new file mode 100644 index 000000000000..80fe5ffd1c64
> > > --- /dev/null
> > > +++ b/drivers/media/i2c/ar0234.c
> > > @@ -0,0 +1,1077 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > > +
> > > +#include <linux/acpi.h>
> > > +#include <linux/clk.h>
> > > +#include <linux/delay.h>
> > > +#include <linux/i2c.h>
> > > +#include <linux/module.h>
> > > +#include <linux/pm_runtime.h>
> > > +#include <asm/unaligned.h>
> > > +
> > > +#include <media/v4l2-cci.h>
> > > +#include <media/v4l2-ctrls.h>
> > > +#include <media/v4l2-event.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +
> > > +/* Chip ID */
> > > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > > +#define AR0234_CHIP_ID			0x0a56
> > > +
> > > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > > +
> > > +#define AR0234_EXPOSURE_MIN		0
> > > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > > +#define AR0234_EXPOSURE_STEP		1
> > > +
> > > +#define AR0234_ANALOG_GAIN_MIN		0
> > > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > > +#define AR0234_ANALOG_GAIN_STEP		1
> > > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > > +
> > > +#define AR0234_GLOBAL_GAIN_MIN		0
> > > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > > +#define AR0234_GLOBAL_GAIN_STEP		1
> > > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > > +
> > > +#define AR0234_NATIVE_WIDTH		1920
> > > +#define AR0234_NATIVE_HEIGHT		1080
> > > +#define AR0234_COMMON_WIDTH		1280
> > > +#define AR0234_COMMON_HEIGHT		960
> > > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > > +#define AR0234_PIXEL_ARRAY_TOP		60
> > > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > > +
> > > +#define AR0234_VTS_DEFAULT		0x04c4
> > > +#define AR0234_VTS_MAX			0xffff
> > > +#define AR0234_HTS_DEFAULT		0x04c4
> > > +#define AR0234_PPL_DEFAULT		3498
> > > +
> > > +#define AR0234_MODE_RESET		0x00d9
> > > +#define AR0234_MODE_STANDBY		0x2058
> > > +#define AR0234_MODE_STREAMING		0x205c
> > > +
> > > +#define AR0234_PIXEL_RATE		128000000ULL
> > > +#define AR0234_XCLK_FREQ		19200000ULL
> > > +
> > > +#define AR0234_TEST_PATTERN_DISABLE	0
> > > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > > +#define AR0234_TEST_PATTERN_WALKING	256
> > > +
> > > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > > +
> > > +struct ar0234_reg_list {
> > > +	u32 num_of_regs;
> > > +	const struct cci_reg_sequence *regs; };
> > > +
> > > +struct ar0234_mode {
> > > +	u32 width;
> > > +	u32 height;
> > > +	u32 hts;
> > > +	u32 vts_def;
> > > +	u32 code;
> > > +	/* Sensor register settings for this mode */
> > > +	const struct ar0234_reg_list reg_list; };
> > > +
> > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > +	{ CCI_REG16(0x3f4c), 0x121f },
> > > +	{ CCI_REG16(0x3f4e), 0x121f },
> > > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > > +	{ CCI_REG16(0x31e0), 0x0003 },
> > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > +	/* R0x3088 specify the sequencer RAM access address. */
> > > +	{ CCI_REG16(0x3088), 0x8000 },
> > > +	/* R0x3086 write the sequencer RAM. */
> > > +	{ CCI_REG16(0x3086), 0xc1ae },
> > > +	{ CCI_REG16(0x3086), 0x327f },
> > > +	{ CCI_REG16(0x3086), 0x5780 },
> > > +	{ CCI_REG16(0x3086), 0x272f },
> > > +	{ CCI_REG16(0x3086), 0x7416 },
> > 
> > Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> > Please move the data out to a
> > 
> > static const u16 ar0234_sequencer[] = {
> > 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > 	...
> > };
> > 
> > table, and program it with
> > 
> > 	/* Program the sequencer. */
> > 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > 			  ar0234_sequencer[i], &ret);
> > 
> > And please define macros for the sequencer access registers 0x3086 and
> > 0x3088, as well as for the bits of the 0x3088 register.
> > 
> > [snip]
>
> [Yan, Dongcheng
  

Hi Larent,

Sorry for that I didn't check my sent items in time, a bug of outlook causes all commets after first quote to be lost. I have edited again and sorry for the delay.
Thanks for your review and meaningful suggestions. I have contacted the vendor and optimized the code related to the register settings.
The response is as follows:

> -----Original Message-----
> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: Friday, June 14, 2024 10:25 PM
> To: Yan, Dongcheng <dongcheng.yan@intel.com>
> Cc: sakari.ailus@linux.intel.com; linux-media@vger.kernel.org;
> tomi.valkeinen@ideasonboard.com; jacopo.mondi@ideasonboard.com;
> bingbu.cao@linux.intel.com; dave.stevenson@raspberrypi.com; Li, Daxing
> <daxing.li@intel.com>; Yao, Hao <hao.yao@intel.com>
> Subject: Re: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
> 
> Hi Dongcheng,
> 
> Thank you for the patch.
> 
> On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > The driver is implemented with V4L2 framework, and supports following
> > features:
> >
> >     - manual exposure and analog/digital gain control
> >     - vblank/hblank control
> >     - vflip/hflip control
> >     - runtime PM support
> >     - 1280x960 at 30FPS
> >
> > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > ---
> > v2 --> v3:
> >     - remove unused reg setting
> >     - add vflip/hflip control
> >     - add external clock check & lanes check
> >
> > ---
> >  drivers/media/i2c/Kconfig  |   11 +
> >  drivers/media/i2c/Makefile |    1 +
> >  drivers/media/i2c/ar0234.c | 1077
> > ++++++++++++++++++++++++++++++++++++
> >  3 files changed, 1089 insertions(+)
> >  create mode 100644 drivers/media/i2c/ar0234.c
> >
> > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > index c6d3ee472d81..7108d194c975 100644
> > --- a/drivers/media/i2c/Kconfig
> > +++ b/drivers/media/i2c/Kconfig
> > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> >  	  To compile this driver as a module, choose M here: the
> >  	  module will be called alvium-csi2.
> >
> > +config VIDEO_AR0234
> > +        tristate "ON Semiconductor AR0234 sensor support"
> > +        depends on ACPI || COMPILE_TEST
> > +        select V4L2_CCI_I2C
> > +        help
> > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > +          AR0234 camera.
> > +
> > +          To compile this driver as a module, choose M here: the
> > +          module will be called ar0234.
> > +
> >  config VIDEO_AR0521
> >  	tristate "ON Semiconductor AR0521 sensor support"
> >  	help
> > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > index dfbe6448b549..57b4f62106d9 100644
> > --- a/drivers/media/i2c/Makefile
> > +++ b/drivers/media/i2c/Makefile
> > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > new file mode 100644 index 000000000000..80fe5ffd1c64
> > --- /dev/null
> > +++ b/drivers/media/i2c/ar0234.c
> > @@ -0,0 +1,1077 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/i2c.h>
> > +#include <linux/module.h>
> > +#include <linux/pm_runtime.h>
> > +#include <asm/unaligned.h>
> > +
> > +#include <media/v4l2-cci.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +
> > +/* Chip ID */
> > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > +#define AR0234_CHIP_ID			0x0a56
> > +
> > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > +
> > +#define AR0234_EXPOSURE_MIN		0
> > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > +#define AR0234_EXPOSURE_STEP		1
> > +
> > +#define AR0234_ANALOG_GAIN_MIN		0
> > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > +#define AR0234_ANALOG_GAIN_STEP		1
> > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > +
> > +#define AR0234_GLOBAL_GAIN_MIN		0
> > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > +#define AR0234_GLOBAL_GAIN_STEP		1
> > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > +
> > +#define AR0234_NATIVE_WIDTH		1920
> > +#define AR0234_NATIVE_HEIGHT		1080
> > +#define AR0234_COMMON_WIDTH		1280
> > +#define AR0234_COMMON_HEIGHT		960
> > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > +#define AR0234_PIXEL_ARRAY_TOP		60
> > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > +
> > +#define AR0234_VTS_DEFAULT		0x04c4
> > +#define AR0234_VTS_MAX			0xffff
> > +#define AR0234_HTS_DEFAULT		0x04c4
> > +#define AR0234_PPL_DEFAULT		3498
> > +
> > +#define AR0234_MODE_RESET		0x00d9
> > +#define AR0234_MODE_STANDBY		0x2058
> > +#define AR0234_MODE_STREAMING		0x205c
> > +
> > +#define AR0234_PIXEL_RATE		128000000ULL
> > +#define AR0234_XCLK_FREQ		19200000ULL
> > +
> > +#define AR0234_TEST_PATTERN_DISABLE	0
> > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > +#define AR0234_TEST_PATTERN_WALKING	256
> > +
> > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > +
> > +struct ar0234_reg_list {
> > +	u32 num_of_regs;
> > +	const struct cci_reg_sequence *regs; };
> > +
> > +struct ar0234_mode {
> > +	u32 width;
> > +	u32 height;
> > +	u32 hts;
> > +	u32 vts_def;
> > +	u32 code;
> > +	/* Sensor register settings for this mode */
> > +	const struct ar0234_reg_list reg_list; };
> > +
> > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > +	{ CCI_REG16(0x3f4c), 0x121f },
> > +	{ CCI_REG16(0x3f4e), 0x121f },
> > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > +	{ CCI_REG16(0x31e0), 0x0003 },
> > +	{ CCI_REG16(0x30b0), 0x0028 },
> > +	/* R0x3088 specify the sequencer RAM access address. */
> > +	{ CCI_REG16(0x3088), 0x8000 },
> > +	/* R0x3086 write the sequencer RAM. */
> > +	{ CCI_REG16(0x3086), 0xc1ae },
> > +	{ CCI_REG16(0x3086), 0x327f },
> > +	{ CCI_REG16(0x3086), 0x5780 },
> > +	{ CCI_REG16(0x3086), 0x272f },
> > +	{ CCI_REG16(0x3086), 0x7416 },
> 
> Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> Please move the data out to a
> 
> static const u16 ar0234_sequencer[] = {
> 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> 	...
> };
> 
> table, and program it with
> 
> 	/* Program the sequencer. */
> 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> 			  ar0234_sequencer[i], &ret);
> 
> And please define macros for the sequencer access registers 0x3086 and
> 0x3088, as well as for the bits of the 0x3088 register.
> 
> [snip]
> 
Through communication with the vendor, we learned that this is a patch (writing to the sequencer) used to optimize the sensor's performance. It is not critical for the driver's normal operation. Therefore, I will remove this patch directly.

> > +	{ CCI_REG16(0x302a), 0x0005 },
> > +	{ CCI_REG16(0x302c), 0x0001 },
> > +	{ CCI_REG16(0x302e), 0x0003 },
> > +	{ CCI_REG16(0x3030), 0x0032 },
> > +	{ CCI_REG16(0x3036), 0x000a },
> > +	{ CCI_REG16(0x3038), 0x0001 },
> > +	{ CCI_REG16(0x30b0), 0x0028 },
> > +	{ CCI_REG16(0x31b0), 0x0082 },
> > +	{ CCI_REG16(0x31b2), 0x005c },
> > +	{ CCI_REG16(0x31b4), 0x5248 },
> > +	{ CCI_REG16(0x31b6), 0x3257 },
> > +	{ CCI_REG16(0x31b8), 0x904b },
> > +	{ CCI_REG16(0x31ba), 0x030b },
> > +	{ CCI_REG16(0x31bc), 0x8e09 },
> > +	{ CCI_REG16(0x3354), 0x002b },
> > +	{ CCI_REG16(0x31d0), 0x0000 },
> > +	{ CCI_REG16(0x31ae), 0x0204 },
> > +	{ CCI_REG16(0x3002), 0x0080 },
> > +	{ CCI_REG16(0x3004), 0x0148 },
> > +	{ CCI_REG16(0x3006), 0x043f },
> > +	{ CCI_REG16(0x3008), 0x0647 },
> > +	{ CCI_REG16(0x3064), 0x1802 },
> > +	{ CCI_REG16(0x300a), 0x04c4 },
> > +	{ CCI_REG16(0x300c), 0x04c4 },
> > +	{ CCI_REG16(0x30a2), 0x0001 },
> > +	{ CCI_REG16(0x30a6), 0x0001 },
> > +	{ CCI_REG16(0x3012), 0x010c },
> > +	{ CCI_REG16(0x3786), 0x0006 },
> > +	{ CCI_REG16(0x31ae), 0x0202 },
> > +	{ CCI_REG16(0x3088), 0x8050 },
> > +	{ CCI_REG16(0x3086), 0x9237 },
> 
> This can stay here if it needs to be programmed separately from the rest of the
> sequencer data, but please use macros to replace the hardcoded register
> addresses, and the value of the 0x3088 register.
> 
> 
I will annotate each of their usages here. These are two recommended common settings provided by the vendor.

> > +	{ CCI_REG16(0x3044), 0x0410 },
> > +	{ CCI_REG16(0x3094), 0x03d4 },
> > +	{ CCI_REG16(0x3096), 0x0280 },
> > +	{ CCI_REG16(0x30ba), 0x7606 },
> > +	{ CCI_REG16(0x30b0), 0x0028 },
> > +	{ CCI_REG16(0x30ba), 0x7600 },
> > +	{ CCI_REG16(0x30fe), 0x002a },
> > +	{ CCI_REG16(0x31de), 0x0410 },
> > +	{ CCI_REG16(0x3ed6), 0x1435 },
> > +	{ CCI_REG16(0x3ed8), 0x9865 },
> > +	{ CCI_REG16(0x3eda), 0x7698 },
> > +	{ CCI_REG16(0x3edc), 0x99ff },
> > +	{ CCI_REG16(0x3ee2), 0xbb88 },
> > +	{ CCI_REG16(0x3ee4), 0x8836 },
> > +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> > +	{ CCI_REG16(0x3ef2), 0x0000 },
> > +	{ CCI_REG16(0x3ef8), 0x6166 },
> > +	{ CCI_REG16(0x3efa), 0x3333 },
> > +	{ CCI_REG16(0x3efc), 0x6634 },
> > +	{ CCI_REG16(0x3088), 0x81ba },
> > +	{ CCI_REG16(0x3086), 0x3d02 },
> 
> Same here.
> 
> > +	{ CCI_REG16(0x3276), 0x05dc },
> > +	{ CCI_REG16(0x3f00), 0x9d05 },
> > +	{ CCI_REG16(0x3ed2), 0xfa86 },
> > +	{ CCI_REG16(0x3eee), 0xa4fe },
> > +	{ CCI_REG16(0x3ecc), 0x6e42 },
> > +	{ CCI_REG16(0x3ecc), 0x0e42 },
> > +	{ CCI_REG16(0x3eec), 0x0c0c },
> > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > +	{ CCI_REG16(0x3180), 0xc24f },
> > +	{ CCI_REG16(0x3102), 0x5000 },
> > +	{ CCI_REG16(0x3060), 0x000d },
> > +	{ CCI_REG16(0x3ed0), 0xff44 },
> > +	{ CCI_REG16(0x3ed2), 0xaa86 },
> > +	{ CCI_REG16(0x3ed4), 0x031f },
> > +	{ CCI_REG16(0x3eee), 0xa4aa },
> 
> Among all the registers above, at least the following need a macro for the
> register name and register bits:
> 
> 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a, 0x302c,
> 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2, 0x30a6, 0x30b0,
> 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2, 0x31b4, 0x31b6, 0x31b8,
> 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> 0x3786
> 
> Some of them should also be handled programmatically, not hardcoded.
> 
Thanks for your comments, I replace all with macros now.

> Ideally, the following registers should also be documented with macros:
> 
> 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> 
Most of the registers you listed cannot be found in the spec, and they work together within the recommended common settings provided by the vendor. Because the functions of these registers are not singular, defining macros not specified in the spec can cause misunderstandings. I add necessary comments to make code more readable.

> 0x30ba, in particular, varies depending on the analog gain and pixel clock, so it
> needs to be handled programmatically.
> 
0x30BA is independent of analog gain and pixel clock. Under the current pixel clock settings, 0x30BA is fixed in spec and set to 0x7606. It would be better to configure it to the recommended value but not crucial (the vendor did not provide a clear explanation whether this is for image quality or performance). handling it should be considered an optimization patch if using more pxlclk configurations in the future.

Thanks,
Dongcheng Yan

> > +};
> > +
> > +static const char * const ar0234_test_pattern_menu[] = {
> > +	"Disabled",
> > +	"Color Bars",
> > +	"Solid Color",
> > +	"Grey Color Bars",
> > +	"Walking 1s",
> > +};
> > +
> > +static const int ar0234_test_pattern_val[] = {
> > +	AR0234_TEST_PATTERN_DISABLE,
> > +	AR0234_TEST_PATTERN_COLOR_BARS,
> > +	AR0234_TEST_PATTERN_SOLID_COLOR,
> > +	AR0234_TEST_PATTERN_GREY_COLOR,
> > +	AR0234_TEST_PATTERN_WALKING,
> > +};
> > +
> > +static const s64 link_freq_menu_items[] = {
> > +	360000000ULL,
> > +};
> > +
> > +static const struct ar0234_mode supported_modes[] = {
> > +	{
> > +		.width = AR0234_COMMON_WIDTH,
> > +		.height = AR0234_COMMON_HEIGHT,
> > +		.hts = AR0234_HTS_DEFAULT,
> > +		.vts_def = AR0234_VTS_DEFAULT,
> > +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > +		.reg_list = {
> > +			.num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > +			.regs = mode_1280x960_10bit_2lane,
> > +		},
> > +	},
> > +};
> > +
> > +struct ar0234 {
> > +	struct v4l2_subdev sd;
> > +	struct media_pad pad;
> > +	struct v4l2_ctrl_handler ctrl_handler;
> > +
> > +	/* V4L2 Controls */
> > +	struct v4l2_ctrl *link_freq;
> > +	struct v4l2_ctrl *exposure;
> > +	struct v4l2_ctrl *hblank;
> > +	struct v4l2_ctrl *vblank;
> > +	struct v4l2_ctrl *vflip;
> > +	struct v4l2_ctrl *hflip;
> > +	struct regmap *regmap;
> > +	unsigned long link_freq_bitmap;
> > +	const struct ar0234_mode *cur_mode;
> > +};
> > +
> > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > +	struct ar0234 *ar0234 =
> > +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +	s64 exposure_max, exposure_def;
> > +	struct v4l2_subdev_state *state;
> > +	const struct v4l2_mbus_framefmt *format;
> > +	int ret;
> > +
> > +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > +	format = v4l2_subdev_state_get_format(state, 0);
> > +
> > +	/* Propagate change of current control to all related controls */
> > +	if (ctrl->id == V4L2_CID_VBLANK) {
> > +		/* Update max exposure while meeting expected vblanking */
> > +		exposure_max = format->height + ctrl->val -
> > +			       AR0234_EXPOSURE_MAX_MARGIN;
> > +		exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> > +		__v4l2_ctrl_modify_range(ar0234->exposure,
> > +					 ar0234->exposure->minimum,
> > +					 exposure_max, ar0234->exposure->step,
> > +					 exposure_def);
> > +	}
> > +
> > +	/* V4L2 controls values will be applied only when power is already up */
> > +	if (!pm_runtime_get_if_in_use(&client->dev))
> > +		return 0;
> > +
> > +	switch (ctrl->id) {
> > +	case V4L2_CID_ANALOGUE_GAIN:
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > +				ctrl->val, NULL);
> > +		break;
> > +
> > +	case V4L2_CID_DIGITAL_GAIN:
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > +				ctrl->val, NULL);
> > +		break;
> > +
> > +	case V4L2_CID_EXPOSURE:
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > +				ctrl->val, NULL);
> > +		break;
> > +
> > +	case V4L2_CID_VBLANK:
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > +				ar0234->cur_mode->height + ctrl->val, NULL);
> > +		break;
> > +
> > +	case V4L2_CID_HFLIP:
> > +	case V4L2_CID_VFLIP:
> > +		u64 reg;
> > +
> > +		ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > +			       &reg, NULL);
> > +		if (ret)
> > +			break;
> > +
> > +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> > +			 AR0234_ORIENTATION_VFLIP);
> > +		if (ar0234->hflip->val)
> > +			reg |= AR0234_ORIENTATION_HFLIP;
> > +		if (ar0234->vflip->val)
> > +			reg |= AR0234_ORIENTATION_VFLIP;
> > +
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > +				reg, NULL);
> > +		break;
> > +
> > +	case V4L2_CID_TEST_PATTERN:
> > +		ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > +				ar0234_test_pattern_val[ctrl->val], NULL);
> > +		break;
> > +
> > +	default:
> > +		ret = -EINVAL;
> > +		break;
> > +	}
> > +
> > +	pm_runtime_put(&client->dev);
> > +
> > +	return ret;
> > +}
> > +
> > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > +	.s_ctrl = ar0234_set_ctrl,
> > +};
> > +
> > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +	struct v4l2_fwnode_device_properties props;
> > +	struct v4l2_ctrl_handler *ctrl_hdlr;
> > +	s64 exposure_max, vblank_max, vblank_def, hblank;
> > +	u32 link_freq_size;
> > +	int ret;
> > +
> > +	ctrl_hdlr = &ar0234->ctrl_handler;
> > +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > +	if (ret)
> > +		return ret;
> > +
> > +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > +						   &ar0234_ctrl_ops,
> > +						   V4L2_CID_LINK_FREQ,
> > +						   link_freq_size, 0,
> > +						   link_freq_menu_items);
> > +	if (ar0234->link_freq)
> > +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > +
> > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_ANALOGUE_GAIN,
> > +			  AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> > +			  AR0234_ANALOG_GAIN_STEP,
> AR0234_ANALOG_GAIN_DEFAULT);
> > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> > +			  AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> > +			  AR0234_GLOBAL_GAIN_STEP,
> AR0234_GLOBAL_GAIN_DEFAULT);
> > +
> > +	exposure_max = ar0234->cur_mode->vts_def -
> AR0234_EXPOSURE_MAX_MARGIN;
> > +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					     V4L2_CID_EXPOSURE,
> > +					     AR0234_EXPOSURE_MIN, exposure_max,
> > +					     AR0234_EXPOSURE_STEP,
> > +					     exposure_max);
> > +
> > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> > +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > +			  AR0234_PIXEL_RATE);
> > +
> > +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > +	vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> > +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> > +					   vblank_def);
> > +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> > +					   hblank);
> > +	if (ar0234->hblank)
> > +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > +
> > +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> > +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> > +
> > +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > +				     V4L2_CID_TEST_PATTERN,
> > +				     ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > +				     0, 0, ar0234_test_pattern_menu);
> > +
> > +	if (ctrl_hdlr->error)
> > +		return ctrl_hdlr->error;
> > +
> > +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > +					      &props);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> > +
> > +	return 0;
> > +}
> > +
> > +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> > +				     struct v4l2_mbus_framefmt *fmt) {
> > +	fmt->width = mode->width;
> > +	fmt->height = mode->height;
> > +	fmt->code = mode->code;
> > +	fmt->field = V4L2_FIELD_NONE;
> > +}
> > +
> > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +	const struct ar0234_reg_list *reg_list;
> > +	int ret;
> > +
> > +	ret = pm_runtime_resume_and_get(&client->dev);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	/*
> > +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> > +	 * the frame being generated will be truncated.
> > +	 */
> > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > +			AR0234_MODE_RESET, NULL);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to reset");
> > +		goto err_rpm_put;
> > +	}
> > +
> > +	usleep_range(1000, 1500);
> > +
> > +	reg_list = &ar0234->cur_mode->reg_list;
> > +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > +				  reg_list->num_of_regs, NULL);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to set mode");
> > +		goto err_rpm_put;
> > +	}
> > +
> > +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > +	if (ret)
> > +		goto err_rpm_put;
> > +
> > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > +			AR0234_MODE_STREAMING, NULL);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to start stream");
> > +		goto err_rpm_put;
> > +	}
> > +
> > +	return 0;
> > +
> > +err_rpm_put:
> > +	pm_runtime_put(&client->dev);
> > +	return ret;
> > +}
> > +
> > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > +	int ret;
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +
> > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > +			AR0234_MODE_STANDBY, NULL);
> > +	if (ret < 0)
> > +		dev_err(&client->dev, "failed to stop stream");
> > +
> > +	pm_runtime_put(&client->dev);
> > +	return ret;
> > +}
> > +
> > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > +	struct v4l2_subdev_state *state;
> > +	int ret = 0;
> > +
> > +	state = v4l2_subdev_lock_and_get_active_state(sd);
> > +
> > +	if (enable)
> > +		ret = ar0234_start_streaming(ar0234);
> > +	else
> > +		ret = ar0234_stop_streaming(ar0234);
> > +
> > +	/* vflip and hflip cannot change during streaming */
> > +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> > +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> > +	v4l2_subdev_unlock_state(state);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > +			     struct v4l2_subdev_state *sd_state,
> > +			     struct v4l2_subdev_format *fmt) {
> > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +	struct v4l2_rect *crop;
> > +	const struct ar0234_mode *mode;
> > +	s64 hblank;
> > +	int ret;
> > +
> > +	mode = v4l2_find_nearest_size(supported_modes,
> > +				      ARRAY_SIZE(supported_modes),
> > +				      width, height,
> > +				      fmt->format.width,
> > +				      fmt->format.height);
> > +
> > +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > +	crop->width = mode->width;
> > +	crop->height = mode->height;
> > +
> > +	ar0234_update_pad_format(mode, &fmt->format);
> > +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > +
> > +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > +		return 0;
> > +
> > +	ar0234->cur_mode = mode;
> > +
> > +	hblank = AR0234_PPL_DEFAULT - mode->width;
> > +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > +				       1, hblank);
> > +	if (ret) {
> > +		dev_err(&client->dev, "HB ctrl range update failed");
> > +		return ret;
> > +	}
> > +
> > +	/* Update limits and set FPS to default */
> > +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > +				       AR0234_VTS_MAX - mode->height, 1,
> > +				       mode->vts_def - mode->height);
> > +	if (ret) {
> > +		dev_err(&client->dev, "VB ctrl range update failed");
> > +		return ret;
> > +	}
> > +
> > +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> > +	if (ret) {
> > +		dev_err(&client->dev, "VB ctrl set failed");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > +				 struct v4l2_subdev_state *sd_state,
> > +				 struct v4l2_subdev_mbus_code_enum *code) {
> > +	if (code->index > 0)
> > +		return -EINVAL;
> > +
> > +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > +
> > +	return 0;
> > +}
> > +
> > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > +				  struct v4l2_subdev_state *sd_state,
> > +				  struct v4l2_subdev_frame_size_enum *fse) {
> > +	if (fse->index >= ARRAY_SIZE(supported_modes))
> > +		return -EINVAL;
> > +
> > +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > +		return -EINVAL;
> > +
> > +	fse->min_width = supported_modes[fse->index].width;
> > +	fse->max_width = fse->min_width;
> > +	fse->min_height = supported_modes[fse->index].height;
> > +	fse->max_height = fse->min_height;
> > +
> > +	return 0;
> > +}
> > +
> > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > +				struct v4l2_subdev_state *state,
> > +				struct v4l2_subdev_selection *sel) {
> > +	switch (sel->target) {
> > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > +	case V4L2_SEL_TGT_CROP_BOUNDS:
> > +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > +		sel->r.width = AR0234_COMMON_WIDTH;
> > +		sel->r.height = AR0234_COMMON_HEIGHT;
> > +		break;
> > +
> > +	case V4L2_SEL_TGT_CROP:
> > +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > +		break;
> > +
> > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > +		sel->r.top = 0;
> > +		sel->r.left = 0;
> > +		sel->r.width = AR0234_NATIVE_WIDTH;
> > +		sel->r.height = AR0234_NATIVE_HEIGHT;
> > +		break;
> > +
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > +			     struct v4l2_subdev_state *sd_state) {
> > +	struct v4l2_subdev_format fmt = {
> > +		.which = V4L2_SUBDEV_FORMAT_TRY,
> > +		.pad = 0,
> > +		.format = {
> > +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > +			.width = AR0234_COMMON_WIDTH,
> > +			.height = AR0234_COMMON_HEIGHT,
> > +		},
> > +	};
> > +
> > +	ar0234_set_format(sd, sd_state, &fmt);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > +	.s_stream = ar0234_set_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > +	.set_fmt = ar0234_set_format,
> > +	.get_fmt = v4l2_subdev_get_fmt,
> > +	.enum_mbus_code = ar0234_enum_mbus_code,
> > +	.enum_frame_size = ar0234_enum_frame_size,
> > +	.get_selection = ar0234_get_selection, };
> > +
> > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > +	.unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > +
> > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > +	.core = &ar0234_core_ops,
> > +	.video = &ar0234_video_ops,
> > +	.pad = &ar0234_pad_ops,
> > +};
> > +
> > +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> > +	.link_validate = v4l2_subdev_link_validate, };
> > +
> > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > +	.init_state = ar0234_init_state,
> > +};
> > +
> > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct device
> > +*dev) {
> > +	struct fwnode_handle *endpoint;
> > +	struct v4l2_fwnode_endpoint bus_cfg = {
> > +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> > +	};
> > +	int ret;
> > +
> > +	endpoint =
> > +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > +						FWNODE_GRAPH_ENDPOINT_NEXT);
> > +	if (!endpoint) {
> > +		dev_err(dev, "endpoint node not found");
> > +		return -EPROBE_DEFER;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > +	if (ret) {
> > +		dev_err(dev, "parsing endpoint node failed");
> > +		goto out_err;
> > +	}
> > +
> > +	/* Check the number of MIPI CSI2 data lanes */
> > +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > +		dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > +		goto out_err;
> > +	}
> > +
> > +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > +				       bus_cfg.nr_of_link_frequencies,
> > +				       link_freq_menu_items,
> > +				       ARRAY_SIZE(link_freq_menu_items),
> > +				       &ar0234->link_freq_bitmap);
> > +	if (ret)
> > +		goto out_err;
> > +
> > +out_err:
> > +	v4l2_fwnode_endpoint_free(&bus_cfg);
> > +	fwnode_handle_put(endpoint);
> > +	return ret;
> > +}
> > +
> > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > +	int ret;
> > +	u64 val;
> > +
> > +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > +	if (ret)
> > +		return ret;
> > +
> > +	if (val != AR0234_CHIP_ID) {
> > +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > +			AR0234_CHIP_ID, val);
> > +		return -ENXIO;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void ar0234_remove(struct i2c_client *client) {
> > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > +
> > +	v4l2_async_unregister_subdev(&ar0234->sd);
> > +	v4l2_subdev_cleanup(sd);
> > +	media_entity_cleanup(&ar0234->sd.entity);
> > +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > +	pm_runtime_disable(&client->dev);
> > +	pm_runtime_set_suspended(&client->dev);
> > +}
> > +
> > +static int ar0234_probe(struct i2c_client *client) {
> > +	struct device *dev = &client->dev;
> > +	struct ar0234 *ar0234;
> > +	struct clk *xclk;
> > +	u32 xclk_freq;
> > +	int ret;
> > +
> > +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > +	if (!ar0234)
> > +		return -ENOMEM;
> > +
> > +	ret = ar0234_parse_fwnode(ar0234, dev);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > +	if (IS_ERR(ar0234->regmap))
> > +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > +				     "failed to init CCI");
> > +
> > +	v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > +
> > +	xclk = devm_clk_get(dev, NULL);
> > +	if (IS_ERR(xclk)) {
> > +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > +		return PTR_ERR(xclk);
> > +	}
> > +
> > +	xclk_freq = clk_get_rate(xclk);
> > +	if (xclk_freq != AR0234_XCLK_FREQ) {
> > +		dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > +		return -EINVAL;
> > +	}
> > +
> > +	/* Check module identity */
> > +	ret = ar0234_identify_module(ar0234);
> > +	if (ret) {
> > +		dev_err(dev, "failed to find sensor: %d", ret);
> > +		return ret;
> > +	}
> > +
> > +	ar0234->cur_mode = &supported_modes[0];
> > +	ret = ar0234_init_controls(ar0234);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to init controls: %d", ret);
> > +		goto probe_error_v4l2_ctrl_handler_free;
> > +	}
> > +
> > +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> > +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > +
> > +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > +	ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > +		goto probe_error_v4l2_ctrl_handler_free;
> > +	}
> > +
> > +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > +	if (ret < 0) {
> > +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> > +		goto probe_error_media_entity_cleanup;
> > +	}
> > +
> > +	/*
> > +	 * Device is already turned on by i2c-core with ACPI domain PM.
> > +	 * Enable runtime PM and turn off the device.
> > +	 */
> > +	pm_runtime_set_active(&client->dev);
> > +	pm_runtime_enable(&client->dev);
> > +	pm_runtime_idle(&client->dev);
> > +
> > +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > +			ret);
> > +		goto probe_error_rpm;
> > +	}
> > +
> > +	return 0;
> > +probe_error_rpm:
> > +	pm_runtime_disable(&client->dev);
> > +	v4l2_subdev_cleanup(&ar0234->sd);
> > +
> > +probe_error_media_entity_cleanup:
> > +	media_entity_cleanup(&ar0234->sd.entity);
> > +
> > +probe_error_v4l2_ctrl_handler_free:
> > +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > +
> > +	return ret;
> > +}
> > +
> > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > +	{ "INTC10C0" },
> > +	{}
> > +};
> > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > +
> > +static struct i2c_driver ar0234_i2c_driver = {
> > +	.driver = {
> > +		.name = "ar0234",
> > +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > +	},
> > +	.probe = ar0234_probe,
> > +	.remove = ar0234_remove,
> > +};
> > +
> > +module_i2c_driver(ar0234_i2c_driver);
> > +
> > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> MODULE_LICENSE("GPL");
> 
> --
> Regards,
> 
> Laurent Pinchart
  

Hello Dongcheng,

On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> Hi Larent,
> 
> Sorry for that I didn't check my sent items in time, a bug of outlook
> causes all commets after first quote to be lost. I have edited again
> and sorry for the delay.

No worries. I'm sorry that you have to use outlook :-)

> Thanks for your review and meaningful suggestions. I have contacted
> the vendor and optimized the code related to the register settings.
> The response is as follows:
> 
> On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > 
> > Hi Dongcheng,
> > 
> > Thank you for the patch.
> > 
> > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > The driver is implemented with V4L2 framework, and supports following
> > > features:
> > >
> > >     - manual exposure and analog/digital gain control
> > >     - vblank/hblank control
> > >     - vflip/hflip control
> > >     - runtime PM support
> > >     - 1280x960 at 30FPS
> > >
> > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > ---
> > > v2 --> v3:
> > >     - remove unused reg setting
> > >     - add vflip/hflip control
> > >     - add external clock check & lanes check
> > >
> > > ---
> > >  drivers/media/i2c/Kconfig  |   11 +
> > >  drivers/media/i2c/Makefile |    1 +
> > >  drivers/media/i2c/ar0234.c | 1077 ++++++++++++++++++++++++++++++++++++
> > >  3 files changed, 1089 insertions(+)
> > >  create mode 100644 drivers/media/i2c/ar0234.c
> > >
> > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > index c6d3ee472d81..7108d194c975 100644
> > > --- a/drivers/media/i2c/Kconfig
> > > +++ b/drivers/media/i2c/Kconfig
> > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > >  	  To compile this driver as a module, choose M here: the
> > >  	  module will be called alvium-csi2.
> > >
> > > +config VIDEO_AR0234
> > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > +        depends on ACPI || COMPILE_TEST
> > > +        select V4L2_CCI_I2C
> > > +        help
> > > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > > +          AR0234 camera.
> > > +
> > > +          To compile this driver as a module, choose M here: the
> > > +          module will be called ar0234.
> > > +
> > >  config VIDEO_AR0521
> > >  	tristate "ON Semiconductor AR0521 sensor support"
> > >  	help
> > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > > index dfbe6448b549..57b4f62106d9 100644
> > > --- a/drivers/media/i2c/Makefile
> > > +++ b/drivers/media/i2c/Makefile
> > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > > new file mode 100644 index 000000000000..80fe5ffd1c64
> > > --- /dev/null
> > > +++ b/drivers/media/i2c/ar0234.c
> > > @@ -0,0 +1,1077 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > > +
> > > +#include <linux/acpi.h>
> > > +#include <linux/clk.h>
> > > +#include <linux/delay.h>
> > > +#include <linux/i2c.h>
> > > +#include <linux/module.h>
> > > +#include <linux/pm_runtime.h>
> > > +#include <asm/unaligned.h>
> > > +
> > > +#include <media/v4l2-cci.h>
> > > +#include <media/v4l2-ctrls.h>
> > > +#include <media/v4l2-event.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +
> > > +/* Chip ID */
> > > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > > +#define AR0234_CHIP_ID			0x0a56
> > > +
> > > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > > +
> > > +#define AR0234_EXPOSURE_MIN		0
> > > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > > +#define AR0234_EXPOSURE_STEP		1
> > > +
> > > +#define AR0234_ANALOG_GAIN_MIN		0
> > > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > > +#define AR0234_ANALOG_GAIN_STEP		1
> > > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > > +
> > > +#define AR0234_GLOBAL_GAIN_MIN		0
> > > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > > +#define AR0234_GLOBAL_GAIN_STEP		1
> > > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > > +
> > > +#define AR0234_NATIVE_WIDTH		1920
> > > +#define AR0234_NATIVE_HEIGHT		1080
> > > +#define AR0234_COMMON_WIDTH		1280
> > > +#define AR0234_COMMON_HEIGHT		960
> > > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > > +#define AR0234_PIXEL_ARRAY_TOP		60
> > > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > > +
> > > +#define AR0234_VTS_DEFAULT		0x04c4
> > > +#define AR0234_VTS_MAX			0xffff
> > > +#define AR0234_HTS_DEFAULT		0x04c4
> > > +#define AR0234_PPL_DEFAULT		3498
> > > +
> > > +#define AR0234_MODE_RESET		0x00d9
> > > +#define AR0234_MODE_STANDBY		0x2058
> > > +#define AR0234_MODE_STREAMING		0x205c
> > > +
> > > +#define AR0234_PIXEL_RATE		128000000ULL
> > > +#define AR0234_XCLK_FREQ		19200000ULL
> > > +
> > > +#define AR0234_TEST_PATTERN_DISABLE	0
> > > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > > +#define AR0234_TEST_PATTERN_WALKING	256
> > > +
> > > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > > +
> > > +struct ar0234_reg_list {
> > > +	u32 num_of_regs;
> > > +	const struct cci_reg_sequence *regs; };
> > > +
> > > +struct ar0234_mode {
> > > +	u32 width;
> > > +	u32 height;
> > > +	u32 hts;
> > > +	u32 vts_def;
> > > +	u32 code;
> > > +	/* Sensor register settings for this mode */
> > > +	const struct ar0234_reg_list reg_list; };
> > > +
> > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > +	{ CCI_REG16(0x3f4c), 0x121f },
> > > +	{ CCI_REG16(0x3f4e), 0x121f },
> > > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > > +	{ CCI_REG16(0x31e0), 0x0003 },
> > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > +	/* R0x3088 specify the sequencer RAM access address. */
> > > +	{ CCI_REG16(0x3088), 0x8000 },
> > > +	/* R0x3086 write the sequencer RAM. */
> > > +	{ CCI_REG16(0x3086), 0xc1ae },
> > > +	{ CCI_REG16(0x3086), 0x327f },
> > > +	{ CCI_REG16(0x3086), 0x5780 },
> > > +	{ CCI_REG16(0x3086), 0x272f },
> > > +	{ CCI_REG16(0x3086), 0x7416 },
> > 
> > Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> > Please move the data out to a
> > 
> > static const u16 ar0234_sequencer[] = {
> > 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > 	...
> > };
> > 
> > table, and program it with
> > 
> > 	/* Program the sequencer. */
> > 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > 			  ar0234_sequencer[i], &ret);
> > 
> > And please define macros for the sequencer access registers 0x3086 and
> > 0x3088, as well as for the bits of the 0x3088 register.
> > 
> > [snip]
>
> Through communication with the vendor, we learned that this is a patch
> (writing to the sequencer) used to optimize the sensor's performance.
> It is not critical for the driver's normal operation. Therefore, I
> will remove this patch directly.

I'm fine dropping it or keeping it, it's up to you. If it improves the
image quality I think it's useful. my only concern is that storing the
register address in every entry wastes space. With an optimized version
that only stores the data, I'm fine having the data in the driver.

> > > +	{ CCI_REG16(0x302a), 0x0005 },
> > > +	{ CCI_REG16(0x302c), 0x0001 },
> > > +	{ CCI_REG16(0x302e), 0x0003 },
> > > +	{ CCI_REG16(0x3030), 0x0032 },
> > > +	{ CCI_REG16(0x3036), 0x000a },
> > > +	{ CCI_REG16(0x3038), 0x0001 },
> > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > +	{ CCI_REG16(0x31b0), 0x0082 },
> > > +	{ CCI_REG16(0x31b2), 0x005c },
> > > +	{ CCI_REG16(0x31b4), 0x5248 },
> > > +	{ CCI_REG16(0x31b6), 0x3257 },
> > > +	{ CCI_REG16(0x31b8), 0x904b },
> > > +	{ CCI_REG16(0x31ba), 0x030b },
> > > +	{ CCI_REG16(0x31bc), 0x8e09 },
> > > +	{ CCI_REG16(0x3354), 0x002b },
> > > +	{ CCI_REG16(0x31d0), 0x0000 },
> > > +	{ CCI_REG16(0x31ae), 0x0204 },
> > > +	{ CCI_REG16(0x3002), 0x0080 },
> > > +	{ CCI_REG16(0x3004), 0x0148 },
> > > +	{ CCI_REG16(0x3006), 0x043f },
> > > +	{ CCI_REG16(0x3008), 0x0647 },
> > > +	{ CCI_REG16(0x3064), 0x1802 },
> > > +	{ CCI_REG16(0x300a), 0x04c4 },
> > > +	{ CCI_REG16(0x300c), 0x04c4 },
> > > +	{ CCI_REG16(0x30a2), 0x0001 },
> > > +	{ CCI_REG16(0x30a6), 0x0001 },
> > > +	{ CCI_REG16(0x3012), 0x010c },
> > > +	{ CCI_REG16(0x3786), 0x0006 },
> > > +	{ CCI_REG16(0x31ae), 0x0202 },
> > > +	{ CCI_REG16(0x3088), 0x8050 },
> > > +	{ CCI_REG16(0x3086), 0x9237 },
> > 
> > This can stay here if it needs to be programmed separately from the rest of the
> > sequencer data, but please use macros to replace the hardcoded register
> > addresses, and the value of the 0x3088 register.
>
> I will annotate each of their usages here. These are two recommended
> common settings provided by the vendor.
> 
> > > +	{ CCI_REG16(0x3044), 0x0410 },
> > > +	{ CCI_REG16(0x3094), 0x03d4 },
> > > +	{ CCI_REG16(0x3096), 0x0280 },
> > > +	{ CCI_REG16(0x30ba), 0x7606 },
> > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > +	{ CCI_REG16(0x30ba), 0x7600 },
> > > +	{ CCI_REG16(0x30fe), 0x002a },
> > > +	{ CCI_REG16(0x31de), 0x0410 },
> > > +	{ CCI_REG16(0x3ed6), 0x1435 },
> > > +	{ CCI_REG16(0x3ed8), 0x9865 },
> > > +	{ CCI_REG16(0x3eda), 0x7698 },
> > > +	{ CCI_REG16(0x3edc), 0x99ff },
> > > +	{ CCI_REG16(0x3ee2), 0xbb88 },
> > > +	{ CCI_REG16(0x3ee4), 0x8836 },
> > > +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> > > +	{ CCI_REG16(0x3ef2), 0x0000 },
> > > +	{ CCI_REG16(0x3ef8), 0x6166 },
> > > +	{ CCI_REG16(0x3efa), 0x3333 },
> > > +	{ CCI_REG16(0x3efc), 0x6634 },
> > > +	{ CCI_REG16(0x3088), 0x81ba },
> > > +	{ CCI_REG16(0x3086), 0x3d02 },
> > 
> > Same here.
> > 
> > > +	{ CCI_REG16(0x3276), 0x05dc },
> > > +	{ CCI_REG16(0x3f00), 0x9d05 },
> > > +	{ CCI_REG16(0x3ed2), 0xfa86 },
> > > +	{ CCI_REG16(0x3eee), 0xa4fe },
> > > +	{ CCI_REG16(0x3ecc), 0x6e42 },
> > > +	{ CCI_REG16(0x3ecc), 0x0e42 },
> > > +	{ CCI_REG16(0x3eec), 0x0c0c },
> > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > +	{ CCI_REG16(0x3180), 0xc24f },
> > > +	{ CCI_REG16(0x3102), 0x5000 },
> > > +	{ CCI_REG16(0x3060), 0x000d },
> > > +	{ CCI_REG16(0x3ed0), 0xff44 },
> > > +	{ CCI_REG16(0x3ed2), 0xaa86 },
> > > +	{ CCI_REG16(0x3ed4), 0x031f },
> > > +	{ CCI_REG16(0x3eee), 0xa4aa },
> > 
> > Among all the registers above, at least the following need a macro for the
> > register name and register bits:
> > 
> > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a, 0x302c,
> > 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2, 0x30a6, 0x30b0,
> > 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2, 0x31b4, 0x31b6, 0x31b8,
> > 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > 0x3786
> > 
> > Some of them should also be handled programmatically, not hardcoded.
>
> Thanks for your comments, I replace all with macros now.
> 
> > Ideally, the following registers should also be documented with macros:
> > 
> > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
>
> Most of the registers you listed cannot be found in the spec, and they
> work together within the recommended common settings provided by the
> vendor. Because the functions of these registers are not singular,
> defining macros not specified in the spec can cause misunderstandings.
> I add necessary comments to make code more readable.

OK I'm fine with that.

> > 0x30ba, in particular, varies depending on the analog gain and pixel
> > clock, so it needs to be handled programmatically.
>
> 0x30BA is independent of analog gain and pixel clock.

Doesn't table 26 in the developer guide show otherwise (for bits [2:0]
at least) ?

> Under the current pixel clock settings, 0x30BA is fixed in spec and
> set to 0x7606.

Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2
MHz. That's a pretty unusual value. Given that the sensor uses a quite
standard PLL model, I think you can use the ccs-pll helper to calculate
the PLL parameters dynamically at runtime. See for instance
https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.pinchart@ideasonboard.com/
for an example of how to do so, for a sensor that has a very similar (if
not identical) PLL topology. Sakari can also help if you have issues
with the ccs-pll helper.

> It would be better to configure it to the recommended value but not
> crucial (the vendor did not provide a clear explanation whether this
> is for image quality or performance). handling it should be considered
> an optimization patch if using more pxlclk configurations in the
> future.
> 
> > > +};
> > > +
> > > +static const char * const ar0234_test_pattern_menu[] = {
> > > +	"Disabled",
> > > +	"Color Bars",
> > > +	"Solid Color",
> > > +	"Grey Color Bars",
> > > +	"Walking 1s",
> > > +};
> > > +
> > > +static const int ar0234_test_pattern_val[] = {
> > > +	AR0234_TEST_PATTERN_DISABLE,
> > > +	AR0234_TEST_PATTERN_COLOR_BARS,
> > > +	AR0234_TEST_PATTERN_SOLID_COLOR,
> > > +	AR0234_TEST_PATTERN_GREY_COLOR,
> > > +	AR0234_TEST_PATTERN_WALKING,
> > > +};
> > > +
> > > +static const s64 link_freq_menu_items[] = {
> > > +	360000000ULL,
> > > +};
> > > +
> > > +static const struct ar0234_mode supported_modes[] = {
> > > +	{
> > > +		.width = AR0234_COMMON_WIDTH,
> > > +		.height = AR0234_COMMON_HEIGHT,
> > > +		.hts = AR0234_HTS_DEFAULT,
> > > +		.vts_def = AR0234_VTS_DEFAULT,
> > > +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > +		.reg_list = {
> > > +			.num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > +			.regs = mode_1280x960_10bit_2lane,
> > > +		},
> > > +	},
> > > +};
> > > +
> > > +struct ar0234 {
> > > +	struct v4l2_subdev sd;
> > > +	struct media_pad pad;
> > > +	struct v4l2_ctrl_handler ctrl_handler;
> > > +
> > > +	/* V4L2 Controls */
> > > +	struct v4l2_ctrl *link_freq;
> > > +	struct v4l2_ctrl *exposure;
> > > +	struct v4l2_ctrl *hblank;
> > > +	struct v4l2_ctrl *vblank;
> > > +	struct v4l2_ctrl *vflip;
> > > +	struct v4l2_ctrl *hflip;
> > > +	struct regmap *regmap;
> > > +	unsigned long link_freq_bitmap;
> > > +	const struct ar0234_mode *cur_mode;
> > > +};
> > > +
> > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > +	struct ar0234 *ar0234 =
> > > +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +	s64 exposure_max, exposure_def;
> > > +	struct v4l2_subdev_state *state;
> > > +	const struct v4l2_mbus_framefmt *format;
> > > +	int ret;
> > > +
> > > +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > +	format = v4l2_subdev_state_get_format(state, 0);
> > > +
> > > +	/* Propagate change of current control to all related controls */
> > > +	if (ctrl->id == V4L2_CID_VBLANK) {
> > > +		/* Update max exposure while meeting expected vblanking */
> > > +		exposure_max = format->height + ctrl->val -
> > > +			       AR0234_EXPOSURE_MAX_MARGIN;
> > > +		exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> > > +		__v4l2_ctrl_modify_range(ar0234->exposure,
> > > +					 ar0234->exposure->minimum,
> > > +					 exposure_max, ar0234->exposure->step,
> > > +					 exposure_def);
> > > +	}
> > > +
> > > +	/* V4L2 controls values will be applied only when power is already up */
> > > +	if (!pm_runtime_get_if_in_use(&client->dev))
> > > +		return 0;
> > > +
> > > +	switch (ctrl->id) {
> > > +	case V4L2_CID_ANALOGUE_GAIN:
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > > +				ctrl->val, NULL);
> > > +		break;
> > > +
> > > +	case V4L2_CID_DIGITAL_GAIN:
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > > +				ctrl->val, NULL);
> > > +		break;
> > > +
> > > +	case V4L2_CID_EXPOSURE:
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > +				ctrl->val, NULL);
> > > +		break;
> > > +
> > > +	case V4L2_CID_VBLANK:
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > +				ar0234->cur_mode->height + ctrl->val, NULL);
> > > +		break;
> > > +
> > > +	case V4L2_CID_HFLIP:
> > > +	case V4L2_CID_VFLIP:
> > > +		u64 reg;
> > > +
> > > +		ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > +			       &reg, NULL);
> > > +		if (ret)
> > > +			break;
> > > +
> > > +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > +			 AR0234_ORIENTATION_VFLIP);
> > > +		if (ar0234->hflip->val)
> > > +			reg |= AR0234_ORIENTATION_HFLIP;
> > > +		if (ar0234->vflip->val)
> > > +			reg |= AR0234_ORIENTATION_VFLIP;
> > > +
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > +				reg, NULL);
> > > +		break;
> > > +
> > > +	case V4L2_CID_TEST_PATTERN:
> > > +		ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > > +				ar0234_test_pattern_val[ctrl->val], NULL);
> > > +		break;
> > > +
> > > +	default:
> > > +		ret = -EINVAL;
> > > +		break;
> > > +	}
> > > +
> > > +	pm_runtime_put(&client->dev);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > +	.s_ctrl = ar0234_set_ctrl,
> > > +};
> > > +
> > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +	struct v4l2_fwnode_device_properties props;
> > > +	struct v4l2_ctrl_handler *ctrl_hdlr;
> > > +	s64 exposure_max, vblank_max, vblank_def, hblank;
> > > +	u32 link_freq_size;
> > > +	int ret;
> > > +
> > > +	ctrl_hdlr = &ar0234->ctrl_handler;
> > > +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > +						   &ar0234_ctrl_ops,
> > > +						   V4L2_CID_LINK_FREQ,
> > > +						   link_freq_size, 0,
> > > +						   link_freq_menu_items);
> > > +	if (ar0234->link_freq)
> > > +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > +
> > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > V4L2_CID_ANALOGUE_GAIN,
> > > +			  AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> > > +			  AR0234_ANALOG_GAIN_STEP,
> > AR0234_ANALOG_GAIN_DEFAULT);
> > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> > > +			  AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> > > +			  AR0234_GLOBAL_GAIN_STEP,
> > AR0234_GLOBAL_GAIN_DEFAULT);
> > > +
> > > +	exposure_max = ar0234->cur_mode->vts_def -
> > AR0234_EXPOSURE_MAX_MARGIN;
> > > +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					     V4L2_CID_EXPOSURE,
> > > +					     AR0234_EXPOSURE_MIN, exposure_max,
> > > +					     AR0234_EXPOSURE_STEP,
> > > +					     exposure_max);
> > > +
> > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> > > +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > +			  AR0234_PIXEL_RATE);
> > > +
> > > +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > +	vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> > > +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > +					   vblank_def);
> > > +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> > > +					   hblank);
> > > +	if (ar0234->hblank)
> > > +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > +
> > > +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > +
> > > +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +				     V4L2_CID_TEST_PATTERN,
> > > +				     ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > > +				     0, 0, ar0234_test_pattern_menu);
> > > +
> > > +	if (ctrl_hdlr->error)
> > > +		return ctrl_hdlr->error;
> > > +
> > > +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > > +					      &props);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> > > +				     struct v4l2_mbus_framefmt *fmt) {
> > > +	fmt->width = mode->width;
> > > +	fmt->height = mode->height;
> > > +	fmt->code = mode->code;
> > > +	fmt->field = V4L2_FIELD_NONE;
> > > +}
> > > +
> > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +	const struct ar0234_reg_list *reg_list;
> > > +	int ret;
> > > +
> > > +	ret = pm_runtime_resume_and_get(&client->dev);
> > > +	if (ret < 0)
> > > +		return ret;
> > > +
> > > +	/*
> > > +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > +	 * the frame being generated will be truncated.
> > > +	 */
> > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > +			AR0234_MODE_RESET, NULL);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "failed to reset");
> > > +		goto err_rpm_put;
> > > +	}
> > > +
> > > +	usleep_range(1000, 1500);
> > > +
> > > +	reg_list = &ar0234->cur_mode->reg_list;
> > > +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > +				  reg_list->num_of_regs, NULL);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "failed to set mode");
> > > +		goto err_rpm_put;
> > > +	}
> > > +
> > > +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > +	if (ret)
> > > +		goto err_rpm_put;
> > > +
> > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > +			AR0234_MODE_STREAMING, NULL);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "failed to start stream");
> > > +		goto err_rpm_put;
> > > +	}
> > > +
> > > +	return 0;
> > > +
> > > +err_rpm_put:
> > > +	pm_runtime_put(&client->dev);
> > > +	return ret;
> > > +}
> > > +
> > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > +	int ret;
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +
> > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > +			AR0234_MODE_STANDBY, NULL);
> > > +	if (ret < 0)
> > > +		dev_err(&client->dev, "failed to stop stream");
> > > +
> > > +	pm_runtime_put(&client->dev);
> > > +	return ret;
> > > +}
> > > +
> > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > +	struct v4l2_subdev_state *state;
> > > +	int ret = 0;
> > > +
> > > +	state = v4l2_subdev_lock_and_get_active_state(sd);
> > > +
> > > +	if (enable)
> > > +		ret = ar0234_start_streaming(ar0234);
> > > +	else
> > > +		ret = ar0234_stop_streaming(ar0234);
> > > +
> > > +	/* vflip and hflip cannot change during streaming */
> > > +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> > > +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> > > +	v4l2_subdev_unlock_state(state);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > +			     struct v4l2_subdev_state *sd_state,
> > > +			     struct v4l2_subdev_format *fmt) {
> > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +	struct v4l2_rect *crop;
> > > +	const struct ar0234_mode *mode;
> > > +	s64 hblank;
> > > +	int ret;
> > > +
> > > +	mode = v4l2_find_nearest_size(supported_modes,
> > > +				      ARRAY_SIZE(supported_modes),
> > > +				      width, height,
> > > +				      fmt->format.width,
> > > +				      fmt->format.height);
> > > +
> > > +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > +	crop->width = mode->width;
> > > +	crop->height = mode->height;
> > > +
> > > +	ar0234_update_pad_format(mode, &fmt->format);
> > > +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > > +
> > > +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > +		return 0;
> > > +
> > > +	ar0234->cur_mode = mode;
> > > +
> > > +	hblank = AR0234_PPL_DEFAULT - mode->width;
> > > +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > > +				       1, hblank);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "HB ctrl range update failed");
> > > +		return ret;
> > > +	}
> > > +
> > > +	/* Update limits and set FPS to default */
> > > +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > +				       AR0234_VTS_MAX - mode->height, 1,
> > > +				       mode->vts_def - mode->height);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "VB ctrl range update failed");
> > > +		return ret;
> > > +	}
> > > +
> > > +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "VB ctrl set failed");
> > > +		return ret;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > +				 struct v4l2_subdev_state *sd_state,
> > > +				 struct v4l2_subdev_mbus_code_enum *code) {
> > > +	if (code->index > 0)
> > > +		return -EINVAL;
> > > +
> > > +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > +				  struct v4l2_subdev_state *sd_state,
> > > +				  struct v4l2_subdev_frame_size_enum *fse) {
> > > +	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > +		return -EINVAL;
> > > +
> > > +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > +		return -EINVAL;
> > > +
> > > +	fse->min_width = supported_modes[fse->index].width;
> > > +	fse->max_width = fse->min_width;
> > > +	fse->min_height = supported_modes[fse->index].height;
> > > +	fse->max_height = fse->min_height;
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > +				struct v4l2_subdev_state *state,
> > > +				struct v4l2_subdev_selection *sel) {
> > > +	switch (sel->target) {
> > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > +	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > +		sel->r.width = AR0234_COMMON_WIDTH;
> > > +		sel->r.height = AR0234_COMMON_HEIGHT;
> > > +		break;
> > > +
> > > +	case V4L2_SEL_TGT_CROP:
> > > +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > +		break;
> > > +
> > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > +		sel->r.top = 0;
> > > +		sel->r.left = 0;
> > > +		sel->r.width = AR0234_NATIVE_WIDTH;
> > > +		sel->r.height = AR0234_NATIVE_HEIGHT;
> > > +		break;
> > > +
> > > +	default:
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > +			     struct v4l2_subdev_state *sd_state) {
> > > +	struct v4l2_subdev_format fmt = {
> > > +		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > +		.pad = 0,
> > > +		.format = {
> > > +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > +			.width = AR0234_COMMON_WIDTH,
> > > +			.height = AR0234_COMMON_HEIGHT,
> > > +		},
> > > +	};
> > > +
> > > +	ar0234_set_format(sd, sd_state, &fmt);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > +	.s_stream = ar0234_set_stream,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > +	.set_fmt = ar0234_set_format,
> > > +	.get_fmt = v4l2_subdev_get_fmt,
> > > +	.enum_mbus_code = ar0234_enum_mbus_code,
> > > +	.enum_frame_size = ar0234_enum_frame_size,
> > > +	.get_selection = ar0234_get_selection, };
> > > +
> > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > +	.unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > +
> > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > +	.core = &ar0234_core_ops,
> > > +	.video = &ar0234_video_ops,
> > > +	.pad = &ar0234_pad_ops,
> > > +};
> > > +
> > > +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> > > +	.link_validate = v4l2_subdev_link_validate, };
> > > +
> > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > +	.init_state = ar0234_init_state,
> > > +};
> > > +
> > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct device
> > > +*dev) {
> > > +	struct fwnode_handle *endpoint;
> > > +	struct v4l2_fwnode_endpoint bus_cfg = {
> > > +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> > > +	};
> > > +	int ret;
> > > +
> > > +	endpoint =
> > > +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > +						FWNODE_GRAPH_ENDPOINT_NEXT);
> > > +	if (!endpoint) {
> > > +		dev_err(dev, "endpoint node not found");
> > > +		return -EPROBE_DEFER;
> > > +	}
> > > +
> > > +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > +	if (ret) {
> > > +		dev_err(dev, "parsing endpoint node failed");
> > > +		goto out_err;
> > > +	}
> > > +
> > > +	/* Check the number of MIPI CSI2 data lanes */
> > > +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > +		dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > > +		goto out_err;
> > > +	}
> > > +
> > > +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > +				       bus_cfg.nr_of_link_frequencies,
> > > +				       link_freq_menu_items,
> > > +				       ARRAY_SIZE(link_freq_menu_items),
> > > +				       &ar0234->link_freq_bitmap);
> > > +	if (ret)
> > > +		goto out_err;
> > > +
> > > +out_err:
> > > +	v4l2_fwnode_endpoint_free(&bus_cfg);
> > > +	fwnode_handle_put(endpoint);
> > > +	return ret;
> > > +}
> > > +
> > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > +	int ret;
> > > +	u64 val;
> > > +
> > > +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	if (val != AR0234_CHIP_ID) {
> > > +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > +			AR0234_CHIP_ID, val);
> > > +		return -ENXIO;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static void ar0234_remove(struct i2c_client *client) {
> > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > +
> > > +	v4l2_async_unregister_subdev(&ar0234->sd);
> > > +	v4l2_subdev_cleanup(sd);
> > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > +	pm_runtime_disable(&client->dev);
> > > +	pm_runtime_set_suspended(&client->dev);
> > > +}
> > > +
> > > +static int ar0234_probe(struct i2c_client *client) {
> > > +	struct device *dev = &client->dev;
> > > +	struct ar0234 *ar0234;
> > > +	struct clk *xclk;
> > > +	u32 xclk_freq;
> > > +	int ret;
> > > +
> > > +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > > +	if (!ar0234)
> > > +		return -ENOMEM;
> > > +
> > > +	ret = ar0234_parse_fwnode(ar0234, dev);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > +	if (IS_ERR(ar0234->regmap))
> > > +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > +				     "failed to init CCI");
> > > +
> > > +	v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > > +
> > > +	xclk = devm_clk_get(dev, NULL);
> > > +	if (IS_ERR(xclk)) {
> > > +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > +		return PTR_ERR(xclk);
> > > +	}
> > > +
> > > +	xclk_freq = clk_get_rate(xclk);
> > > +	if (xclk_freq != AR0234_XCLK_FREQ) {
> > > +		dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	/* Check module identity */
> > > +	ret = ar0234_identify_module(ar0234);
> > > +	if (ret) {
> > > +		dev_err(dev, "failed to find sensor: %d", ret);
> > > +		return ret;
> > > +	}
> > > +
> > > +	ar0234->cur_mode = &supported_modes[0];
> > > +	ret = ar0234_init_controls(ar0234);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "failed to init controls: %d", ret);
> > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > +	}
> > > +
> > > +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > +
> > > +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > +	ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > > +	if (ret) {
> > > +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > +	}
> > > +
> > > +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > +	if (ret < 0) {
> > > +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > +		goto probe_error_media_entity_cleanup;
> > > +	}
> > > +
> > > +	/*
> > > +	 * Device is already turned on by i2c-core with ACPI domain PM.
> > > +	 * Enable runtime PM and turn off the device.
> > > +	 */
> > > +	pm_runtime_set_active(&client->dev);
> > > +	pm_runtime_enable(&client->dev);
> > > +	pm_runtime_idle(&client->dev);
> > > +
> > > +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > +	if (ret < 0) {
> > > +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > +			ret);
> > > +		goto probe_error_rpm;
> > > +	}
> > > +
> > > +	return 0;
> > > +probe_error_rpm:
> > > +	pm_runtime_disable(&client->dev);
> > > +	v4l2_subdev_cleanup(&ar0234->sd);
> > > +
> > > +probe_error_media_entity_cleanup:
> > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > +
> > > +probe_error_v4l2_ctrl_handler_free:
> > > +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > +	{ "INTC10C0" },
> > > +	{}
> > > +};
> > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > +
> > > +static struct i2c_driver ar0234_i2c_driver = {
> > > +	.driver = {
> > > +		.name = "ar0234",
> > > +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > +	},
> > > +	.probe = ar0234_probe,
> > > +	.remove = ar0234_remove,
> > > +};
> > > +
> > > +module_i2c_driver(ar0234_i2c_driver);
> > > +
> > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > MODULE_LICENSE("GPL");
  

Hi Laurent

On Mon, 1 Jul 2024 at 14:57, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hello Dongcheng,
>
> On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> > Hi Larent,
> >
> > Sorry for that I didn't check my sent items in time, a bug of outlook
> > causes all commets after first quote to be lost. I have edited again
> > and sorry for the delay.
>
> No worries. I'm sorry that you have to use outlook :-)
>
> > Thanks for your review and meaningful suggestions. I have contacted
> > the vendor and optimized the code related to the register settings.
> > The response is as follows:
> >
> > On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > >
> > > Hi Dongcheng,
> > >
> > > Thank you for the patch.
> > >
> > > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > > The driver is implemented with V4L2 framework, and supports following
> > > > features:
> > > >
> > > >     - manual exposure and analog/digital gain control
> > > >     - vblank/hblank control
> > > >     - vflip/hflip control
> > > >     - runtime PM support
> > > >     - 1280x960 at 30FPS
> > > >
> > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > > ---
> > > > v2 --> v3:
> > > >     - remove unused reg setting
> > > >     - add vflip/hflip control
> > > >     - add external clock check & lanes check
> > > >
> > > > ---
> > > >  drivers/media/i2c/Kconfig  |   11 +
> > > >  drivers/media/i2c/Makefile |    1 +
> > > >  drivers/media/i2c/ar0234.c | 1077 ++++++++++++++++++++++++++++++++++++
> > > >  3 files changed, 1089 insertions(+)
> > > >  create mode 100644 drivers/media/i2c/ar0234.c
> > > >
> > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > > index c6d3ee472d81..7108d194c975 100644
> > > > --- a/drivers/media/i2c/Kconfig
> > > > +++ b/drivers/media/i2c/Kconfig
> > > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > > >     To compile this driver as a module, choose M here: the
> > > >     module will be called alvium-csi2.
> > > >
> > > > +config VIDEO_AR0234
> > > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > > +        depends on ACPI || COMPILE_TEST
> > > > +        select V4L2_CCI_I2C
> > > > +        help
> > > > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > > > +          AR0234 camera.
> > > > +
> > > > +          To compile this driver as a module, choose M here: the
> > > > +          module will be called ar0234.
> > > > +
> > > >  config VIDEO_AR0521
> > > >   tristate "ON Semiconductor AR0521 sensor support"
> > > >   help
> > > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > > > index dfbe6448b549..57b4f62106d9 100644
> > > > --- a/drivers/media/i2c/Makefile
> > > > +++ b/drivers/media/i2c/Makefile
> > > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > > > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > > > new file mode 100644 index 000000000000..80fe5ffd1c64
> > > > --- /dev/null
> > > > +++ b/drivers/media/i2c/ar0234.c
> > > > @@ -0,0 +1,1077 @@
> > > > +// SPDX-License-Identifier: GPL-2.0
> > > > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > > > +
> > > > +#include <linux/acpi.h>
> > > > +#include <linux/clk.h>
> > > > +#include <linux/delay.h>
> > > > +#include <linux/i2c.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/pm_runtime.h>
> > > > +#include <asm/unaligned.h>
> > > > +
> > > > +#include <media/v4l2-cci.h>
> > > > +#include <media/v4l2-ctrls.h>
> > > > +#include <media/v4l2-event.h>
> > > > +#include <media/v4l2-device.h>
> > > > +#include <media/v4l2-fwnode.h>
> > > > +
> > > > +/* Chip ID */
> > > > +#define AR0234_REG_CHIP_ID               CCI_REG16(0x3000)
> > > > +#define AR0234_CHIP_ID                   0x0a56
> > > > +
> > > > +#define AR0234_REG_MODE_SELECT           CCI_REG16(0x301a)
> > > > +#define AR0234_REG_VTS                   CCI_REG16(0x300a)
> > > > +#define AR0234_REG_EXPOSURE              CCI_REG16(0x3012)
> > > > +#define AR0234_REG_ANALOG_GAIN           CCI_REG16(0x3060)
> > > > +#define AR0234_REG_GLOBAL_GAIN           CCI_REG16(0x305e)
> > > > +#define AR0234_REG_ORIENTATION           CCI_REG16(0x3040)
> > > > +#define AR0234_REG_TEST_PATTERN          CCI_REG16(0x0600)
> > > > +
> > > > +#define AR0234_EXPOSURE_MIN              0
> > > > +#define AR0234_EXPOSURE_MAX_MARGIN       80
> > > > +#define AR0234_EXPOSURE_STEP             1
> > > > +
> > > > +#define AR0234_ANALOG_GAIN_MIN           0
> > > > +#define AR0234_ANALOG_GAIN_MAX           0x7f
> > > > +#define AR0234_ANALOG_GAIN_STEP          1
> > > > +#define AR0234_ANALOG_GAIN_DEFAULT       0xe
> > > > +
> > > > +#define AR0234_GLOBAL_GAIN_MIN           0
> > > > +#define AR0234_GLOBAL_GAIN_MAX           0x7ff
> > > > +#define AR0234_GLOBAL_GAIN_STEP          1
> > > > +#define AR0234_GLOBAL_GAIN_DEFAULT       0x80
> > > > +
> > > > +#define AR0234_NATIVE_WIDTH              1920
> > > > +#define AR0234_NATIVE_HEIGHT             1080
> > > > +#define AR0234_COMMON_WIDTH              1280
> > > > +#define AR0234_COMMON_HEIGHT             960
> > > > +#define AR0234_PIXEL_ARRAY_LEFT          320
> > > > +#define AR0234_PIXEL_ARRAY_TOP           60
> > > > +#define AR0234_ORIENTATION_HFLIP BIT(14)
> > > > +#define AR0234_ORIENTATION_VFLIP BIT(15)
> > > > +
> > > > +#define AR0234_VTS_DEFAULT               0x04c4
> > > > +#define AR0234_VTS_MAX                   0xffff
> > > > +#define AR0234_HTS_DEFAULT               0x04c4
> > > > +#define AR0234_PPL_DEFAULT               3498
> > > > +
> > > > +#define AR0234_MODE_RESET                0x00d9
> > > > +#define AR0234_MODE_STANDBY              0x2058
> > > > +#define AR0234_MODE_STREAMING            0x205c
> > > > +
> > > > +#define AR0234_PIXEL_RATE                128000000ULL
> > > > +#define AR0234_XCLK_FREQ         19200000ULL
> > > > +
> > > > +#define AR0234_TEST_PATTERN_DISABLE      0
> > > > +#define AR0234_TEST_PATTERN_SOLID_COLOR  1
> > > > +#define AR0234_TEST_PATTERN_COLOR_BARS   2
> > > > +#define AR0234_TEST_PATTERN_GREY_COLOR   3
> > > > +#define AR0234_TEST_PATTERN_WALKING      256
> > > > +
> > > > +#define to_ar0234(_sd)   container_of(_sd, struct ar0234, sd)
> > > > +
> > > > +struct ar0234_reg_list {
> > > > + u32 num_of_regs;
> > > > + const struct cci_reg_sequence *regs; };
> > > > +
> > > > +struct ar0234_mode {
> > > > + u32 width;
> > > > + u32 height;
> > > > + u32 hts;
> > > > + u32 vts_def;
> > > > + u32 code;
> > > > + /* Sensor register settings for this mode */
> > > > + const struct ar0234_reg_list reg_list; };
> > > > +
> > > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > > + { CCI_REG16(0x3f4c), 0x121f },
> > > > + { CCI_REG16(0x3f4e), 0x121f },
> > > > + { CCI_REG16(0x3f50), 0x0b81 },
> > > > + { CCI_REG16(0x31e0), 0x0003 },
> > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > + /* R0x3088 specify the sequencer RAM access address. */
> > > > + { CCI_REG16(0x3088), 0x8000 },
> > > > + /* R0x3086 write the sequencer RAM. */
> > > > + { CCI_REG16(0x3086), 0xc1ae },
> > > > + { CCI_REG16(0x3086), 0x327f },
> > > > + { CCI_REG16(0x3086), 0x5780 },
> > > > + { CCI_REG16(0x3086), 0x272f },
> > > > + { CCI_REG16(0x3086), 0x7416 },
> > >
> > > Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> > > Please move the data out to a
> > >
> > > static const u16 ar0234_sequencer[] = {
> > >     0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > >     ...
> > > };
> > >
> > > table, and program it with
> > >
> > >     /* Program the sequencer. */
> > >     cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > >     for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > >             cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > >                       ar0234_sequencer[i], &ret);
> > >
> > > And please define macros for the sequencer access registers 0x3086 and
> > > 0x3088, as well as for the bits of the 0x3088 register.
> > >
> > > [snip]
> >
> > Through communication with the vendor, we learned that this is a patch
> > (writing to the sequencer) used to optimize the sensor's performance.
> > It is not critical for the driver's normal operation. Therefore, I
> > will remove this patch directly.
>
> I'm fine dropping it or keeping it, it's up to you. If it improves the
> image quality I think it's useful. my only concern is that storing the
> register address in every entry wastes space. With an optimized version
> that only stores the data, I'm fine having the data in the driver.
>
> > > > + { CCI_REG16(0x302a), 0x0005 },
> > > > + { CCI_REG16(0x302c), 0x0001 },
> > > > + { CCI_REG16(0x302e), 0x0003 },
> > > > + { CCI_REG16(0x3030), 0x0032 },
> > > > + { CCI_REG16(0x3036), 0x000a },
> > > > + { CCI_REG16(0x3038), 0x0001 },
> > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > + { CCI_REG16(0x31b0), 0x0082 },
> > > > + { CCI_REG16(0x31b2), 0x005c },
> > > > + { CCI_REG16(0x31b4), 0x5248 },
> > > > + { CCI_REG16(0x31b6), 0x3257 },
> > > > + { CCI_REG16(0x31b8), 0x904b },
> > > > + { CCI_REG16(0x31ba), 0x030b },
> > > > + { CCI_REG16(0x31bc), 0x8e09 },
> > > > + { CCI_REG16(0x3354), 0x002b },
> > > > + { CCI_REG16(0x31d0), 0x0000 },
> > > > + { CCI_REG16(0x31ae), 0x0204 },
> > > > + { CCI_REG16(0x3002), 0x0080 },
> > > > + { CCI_REG16(0x3004), 0x0148 },
> > > > + { CCI_REG16(0x3006), 0x043f },
> > > > + { CCI_REG16(0x3008), 0x0647 },
> > > > + { CCI_REG16(0x3064), 0x1802 },
> > > > + { CCI_REG16(0x300a), 0x04c4 },
> > > > + { CCI_REG16(0x300c), 0x04c4 },
> > > > + { CCI_REG16(0x30a2), 0x0001 },
> > > > + { CCI_REG16(0x30a6), 0x0001 },
> > > > + { CCI_REG16(0x3012), 0x010c },
> > > > + { CCI_REG16(0x3786), 0x0006 },
> > > > + { CCI_REG16(0x31ae), 0x0202 },
> > > > + { CCI_REG16(0x3088), 0x8050 },
> > > > + { CCI_REG16(0x3086), 0x9237 },
> > >
> > > This can stay here if it needs to be programmed separately from the rest of the
> > > sequencer data, but please use macros to replace the hardcoded register
> > > addresses, and the value of the 0x3088 register.
> >
> > I will annotate each of their usages here. These are two recommended
> > common settings provided by the vendor.
> >
> > > > + { CCI_REG16(0x3044), 0x0410 },
> > > > + { CCI_REG16(0x3094), 0x03d4 },
> > > > + { CCI_REG16(0x3096), 0x0280 },
> > > > + { CCI_REG16(0x30ba), 0x7606 },
> > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > + { CCI_REG16(0x30ba), 0x7600 },
> > > > + { CCI_REG16(0x30fe), 0x002a },
> > > > + { CCI_REG16(0x31de), 0x0410 },
> > > > + { CCI_REG16(0x3ed6), 0x1435 },
> > > > + { CCI_REG16(0x3ed8), 0x9865 },
> > > > + { CCI_REG16(0x3eda), 0x7698 },
> > > > + { CCI_REG16(0x3edc), 0x99ff },
> > > > + { CCI_REG16(0x3ee2), 0xbb88 },
> > > > + { CCI_REG16(0x3ee4), 0x8836 },
> > > > + { CCI_REG16(0x3ef0), 0x1cf0 },
> > > > + { CCI_REG16(0x3ef2), 0x0000 },
> > > > + { CCI_REG16(0x3ef8), 0x6166 },
> > > > + { CCI_REG16(0x3efa), 0x3333 },
> > > > + { CCI_REG16(0x3efc), 0x6634 },
> > > > + { CCI_REG16(0x3088), 0x81ba },
> > > > + { CCI_REG16(0x3086), 0x3d02 },
> > >
> > > Same here.
> > >
> > > > + { CCI_REG16(0x3276), 0x05dc },
> > > > + { CCI_REG16(0x3f00), 0x9d05 },
> > > > + { CCI_REG16(0x3ed2), 0xfa86 },
> > > > + { CCI_REG16(0x3eee), 0xa4fe },
> > > > + { CCI_REG16(0x3ecc), 0x6e42 },
> > > > + { CCI_REG16(0x3ecc), 0x0e42 },
> > > > + { CCI_REG16(0x3eec), 0x0c0c },
> > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > + { CCI_REG16(0x3ee6), 0x3363 },
> > > > + { CCI_REG16(0x3ee6), 0x3363 },
> > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > + { CCI_REG16(0x3180), 0xc24f },
> > > > + { CCI_REG16(0x3102), 0x5000 },
> > > > + { CCI_REG16(0x3060), 0x000d },
> > > > + { CCI_REG16(0x3ed0), 0xff44 },
> > > > + { CCI_REG16(0x3ed2), 0xaa86 },
> > > > + { CCI_REG16(0x3ed4), 0x031f },
> > > > + { CCI_REG16(0x3eee), 0xa4aa },
> > >
> > > Among all the registers above, at least the following need a macro for the
> > > register name and register bits:
> > >
> > > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a, 0x302c,
> > > 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2, 0x30a6, 0x30b0,
> > > 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2, 0x31b4, 0x31b6, 0x31b8,
> > > 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > > 0x3786
> > >
> > > Some of them should also be handled programmatically, not hardcoded.
> >
> > Thanks for your comments, I replace all with macros now.
> >
> > > Ideally, the following registers should also be documented with macros:
> > >
> > > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> >
> > Most of the registers you listed cannot be found in the spec, and they
> > work together within the recommended common settings provided by the
> > vendor. Because the functions of these registers are not singular,
> > defining macros not specified in the spec can cause misunderstandings.
> > I add necessary comments to make code more readable.
>
> OK I'm fine with that.
>
> > > 0x30ba, in particular, varies depending on the analog gain and pixel
> > > clock, so it needs to be handled programmatically.
> >
> > 0x30BA is independent of analog gain and pixel clock.
>
> Doesn't table 26 in the developer guide show otherwise (for bits [2:0]
> at least) ?

I'll agree with you, but only if the pixel clock (not rate) is not 90MHz.
I haven't read through this version of the patch set to work out what
the pixel clock is configured as. I'd queried all the clock setup and
timing values in v2 as they looked odd.

> > Under the current pixel clock settings, 0x30BA is fixed in spec and
> > set to 0x7606.

The bottom 3 bits being fixed at 0x6 is fine if the pixel clock is 45
or 22.5MHz according to table 26.

> Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2
> MHz. That's a pretty unusual value.

Not that unusual.
If you check the mainline drivers, you'll find imx258, imx319, imx355,
og01a1b, ov08x40, ov5670, ov5675, ov5693, and a number of others all
use 19.2MHz clock inputs.
There's a common element in which company submitted all those drivers....

  Dave

> Given that the sensor uses a quite
> standard PLL model, I think you can use the ccs-pll helper to calculate
> the PLL parameters dynamically at runtime. See for instance
> https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.pinchart@ideasonboard.com/
> for an example of how to do so, for a sensor that has a very similar (if
> not identical) PLL topology. Sakari can also help if you have issues
> with the ccs-pll helper.
>
> > It would be better to configure it to the recommended value but not
> > crucial (the vendor did not provide a clear explanation whether this
> > is for image quality or performance). handling it should be considered
> > an optimization patch if using more pxlclk configurations in the
> > future.
> >
> > > > +};
> > > > +
> > > > +static const char * const ar0234_test_pattern_menu[] = {
> > > > + "Disabled",
> > > > + "Color Bars",
> > > > + "Solid Color",
> > > > + "Grey Color Bars",
> > > > + "Walking 1s",
> > > > +};
> > > > +
> > > > +static const int ar0234_test_pattern_val[] = {
> > > > + AR0234_TEST_PATTERN_DISABLE,
> > > > + AR0234_TEST_PATTERN_COLOR_BARS,
> > > > + AR0234_TEST_PATTERN_SOLID_COLOR,
> > > > + AR0234_TEST_PATTERN_GREY_COLOR,
> > > > + AR0234_TEST_PATTERN_WALKING,
> > > > +};
> > > > +
> > > > +static const s64 link_freq_menu_items[] = {
> > > > + 360000000ULL,
> > > > +};
> > > > +
> > > > +static const struct ar0234_mode supported_modes[] = {
> > > > + {
> > > > +         .width = AR0234_COMMON_WIDTH,
> > > > +         .height = AR0234_COMMON_HEIGHT,
> > > > +         .hts = AR0234_HTS_DEFAULT,
> > > > +         .vts_def = AR0234_VTS_DEFAULT,
> > > > +         .code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > +         .reg_list = {
> > > > +                 .num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > > +                 .regs = mode_1280x960_10bit_2lane,
> > > > +         },
> > > > + },
> > > > +};
> > > > +
> > > > +struct ar0234 {
> > > > + struct v4l2_subdev sd;
> > > > + struct media_pad pad;
> > > > + struct v4l2_ctrl_handler ctrl_handler;
> > > > +
> > > > + /* V4L2 Controls */
> > > > + struct v4l2_ctrl *link_freq;
> > > > + struct v4l2_ctrl *exposure;
> > > > + struct v4l2_ctrl *hblank;
> > > > + struct v4l2_ctrl *vblank;
> > > > + struct v4l2_ctrl *vflip;
> > > > + struct v4l2_ctrl *hflip;
> > > > + struct regmap *regmap;
> > > > + unsigned long link_freq_bitmap;
> > > > + const struct ar0234_mode *cur_mode;
> > > > +};
> > > > +
> > > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > > + struct ar0234 *ar0234 =
> > > > +         container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > + s64 exposure_max, exposure_def;
> > > > + struct v4l2_subdev_state *state;
> > > > + const struct v4l2_mbus_framefmt *format;
> > > > + int ret;
> > > > +
> > > > + state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > > + format = v4l2_subdev_state_get_format(state, 0);
> > > > +
> > > > + /* Propagate change of current control to all related controls */
> > > > + if (ctrl->id == V4L2_CID_VBLANK) {
> > > > +         /* Update max exposure while meeting expected vblanking */
> > > > +         exposure_max = format->height + ctrl->val -
> > > > +                        AR0234_EXPOSURE_MAX_MARGIN;
> > > > +         exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> > > > +         __v4l2_ctrl_modify_range(ar0234->exposure,
> > > > +                                  ar0234->exposure->minimum,
> > > > +                                  exposure_max, ar0234->exposure->step,
> > > > +                                  exposure_def);
> > > > + }
> > > > +
> > > > + /* V4L2 controls values will be applied only when power is already up */
> > > > + if (!pm_runtime_get_if_in_use(&client->dev))
> > > > +         return 0;
> > > > +
> > > > + switch (ctrl->id) {
> > > > + case V4L2_CID_ANALOGUE_GAIN:
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > > > +                         ctrl->val, NULL);
> > > > +         break;
> > > > +
> > > > + case V4L2_CID_DIGITAL_GAIN:
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > > > +                         ctrl->val, NULL);
> > > > +         break;
> > > > +
> > > > + case V4L2_CID_EXPOSURE:
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > > +                         ctrl->val, NULL);
> > > > +         break;
> > > > +
> > > > + case V4L2_CID_VBLANK:
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > > +                         ar0234->cur_mode->height + ctrl->val, NULL);
> > > > +         break;
> > > > +
> > > > + case V4L2_CID_HFLIP:
> > > > + case V4L2_CID_VFLIP:
> > > > +         u64 reg;
> > > > +
> > > > +         ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > +                        &reg, NULL);
> > > > +         if (ret)
> > > > +                 break;
> > > > +
> > > > +         reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > > +                  AR0234_ORIENTATION_VFLIP);
> > > > +         if (ar0234->hflip->val)
> > > > +                 reg |= AR0234_ORIENTATION_HFLIP;
> > > > +         if (ar0234->vflip->val)
> > > > +                 reg |= AR0234_ORIENTATION_VFLIP;
> > > > +
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > +                         reg, NULL);
> > > > +         break;
> > > > +
> > > > + case V4L2_CID_TEST_PATTERN:
> > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > > > +                         ar0234_test_pattern_val[ctrl->val], NULL);
> > > > +         break;
> > > > +
> > > > + default:
> > > > +         ret = -EINVAL;
> > > > +         break;
> > > > + }
> > > > +
> > > > + pm_runtime_put(&client->dev);
> > > > +
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > > + .s_ctrl = ar0234_set_ctrl,
> > > > +};
> > > > +
> > > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > + struct v4l2_fwnode_device_properties props;
> > > > + struct v4l2_ctrl_handler *ctrl_hdlr;
> > > > + s64 exposure_max, vblank_max, vblank_def, hblank;
> > > > + u32 link_freq_size;
> > > > + int ret;
> > > > +
> > > > + ctrl_hdlr = &ar0234->ctrl_handler;
> > > > + ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > > + if (ret)
> > > > +         return ret;
> > > > +
> > > > + link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > > + ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > > +                                            &ar0234_ctrl_ops,
> > > > +                                            V4L2_CID_LINK_FREQ,
> > > > +                                            link_freq_size, 0,
> > > > +                                            link_freq_menu_items);
> > > > + if (ar0234->link_freq)
> > > > +         ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > +
> > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > V4L2_CID_ANALOGUE_GAIN,
> > > > +                   AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> > > > +                   AR0234_ANALOG_GAIN_STEP,
> > > AR0234_ANALOG_GAIN_DEFAULT);
> > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> > > > +                   AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> > > > +                   AR0234_GLOBAL_GAIN_STEP,
> > > AR0234_GLOBAL_GAIN_DEFAULT);
> > > > +
> > > > + exposure_max = ar0234->cur_mode->vts_def -
> > > AR0234_EXPOSURE_MAX_MARGIN;
> > > > + ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                      V4L2_CID_EXPOSURE,
> > > > +                                      AR0234_EXPOSURE_MIN, exposure_max,
> > > > +                                      AR0234_EXPOSURE_STEP,
> > > > +                                      exposure_max);
> > > > +
> > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> > > > +                   AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > > +                   AR0234_PIXEL_RATE);
> > > > +
> > > > + vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > > + vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> > > > + ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                    V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > > +                                    vblank_def);
> > > > + hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > > + ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                    V4L2_CID_HBLANK, hblank, hblank, 1,
> > > > +                                    hblank);
> > > > + if (ar0234->hblank)
> > > > +         ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > +
> > > > + ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                   V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > > + ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                   V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > > +
> > > > + v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                              V4L2_CID_TEST_PATTERN,
> > > > +                              ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > > > +                              0, 0, ar0234_test_pattern_menu);
> > > > +
> > > > + if (ctrl_hdlr->error)
> > > > +         return ctrl_hdlr->error;
> > > > +
> > > > + ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > > + if (ret)
> > > > +         return ret;
> > > > +
> > > > + ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +                                       &props);
> > > > + if (ret)
> > > > +         return ret;
> > > > +
> > > > + ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> > > > +                              struct v4l2_mbus_framefmt *fmt) {
> > > > + fmt->width = mode->width;
> > > > + fmt->height = mode->height;
> > > > + fmt->code = mode->code;
> > > > + fmt->field = V4L2_FIELD_NONE;
> > > > +}
> > > > +
> > > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > + const struct ar0234_reg_list *reg_list;
> > > > + int ret;
> > > > +
> > > > + ret = pm_runtime_resume_and_get(&client->dev);
> > > > + if (ret < 0)
> > > > +         return ret;
> > > > +
> > > > + /*
> > > > +  * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > > +  * the frame being generated will be truncated.
> > > > +  */
> > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +                 AR0234_MODE_RESET, NULL);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "failed to reset");
> > > > +         goto err_rpm_put;
> > > > + }
> > > > +
> > > > + usleep_range(1000, 1500);
> > > > +
> > > > + reg_list = &ar0234->cur_mode->reg_list;
> > > > + ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > > +                           reg_list->num_of_regs, NULL);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "failed to set mode");
> > > > +         goto err_rpm_put;
> > > > + }
> > > > +
> > > > + ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > > + if (ret)
> > > > +         goto err_rpm_put;
> > > > +
> > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +                 AR0234_MODE_STREAMING, NULL);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "failed to start stream");
> > > > +         goto err_rpm_put;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +
> > > > +err_rpm_put:
> > > > + pm_runtime_put(&client->dev);
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > > + int ret;
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +
> > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +                 AR0234_MODE_STANDBY, NULL);
> > > > + if (ret < 0)
> > > > +         dev_err(&client->dev, "failed to stop stream");
> > > > +
> > > > + pm_runtime_put(&client->dev);
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > + struct v4l2_subdev_state *state;
> > > > + int ret = 0;
> > > > +
> > > > + state = v4l2_subdev_lock_and_get_active_state(sd);
> > > > +
> > > > + if (enable)
> > > > +         ret = ar0234_start_streaming(ar0234);
> > > > + else
> > > > +         ret = ar0234_stop_streaming(ar0234);
> > > > +
> > > > + /* vflip and hflip cannot change during streaming */
> > > > + __v4l2_ctrl_grab(ar0234->vflip, enable);
> > > > + __v4l2_ctrl_grab(ar0234->hflip, enable);
> > > > + v4l2_subdev_unlock_state(state);
> > > > +
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > > +                      struct v4l2_subdev_state *sd_state,
> > > > +                      struct v4l2_subdev_format *fmt) {
> > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > + struct v4l2_rect *crop;
> > > > + const struct ar0234_mode *mode;
> > > > + s64 hblank;
> > > > + int ret;
> > > > +
> > > > + mode = v4l2_find_nearest_size(supported_modes,
> > > > +                               ARRAY_SIZE(supported_modes),
> > > > +                               width, height,
> > > > +                               fmt->format.width,
> > > > +                               fmt->format.height);
> > > > +
> > > > + crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > > + crop->width = mode->width;
> > > > + crop->height = mode->height;
> > > > +
> > > > + ar0234_update_pad_format(mode, &fmt->format);
> > > > + *v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > > > +
> > > > + if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > > +         return 0;
> > > > +
> > > > + ar0234->cur_mode = mode;
> > > > +
> > > > + hblank = AR0234_PPL_DEFAULT - mode->width;
> > > > + ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > > > +                                1, hblank);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "HB ctrl range update failed");
> > > > +         return ret;
> > > > + }
> > > > +
> > > > + /* Update limits and set FPS to default */
> > > > + ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > > +                                AR0234_VTS_MAX - mode->height, 1,
> > > > +                                mode->vts_def - mode->height);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "VB ctrl range update failed");
> > > > +         return ret;
> > > > + }
> > > > +
> > > > + ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "VB ctrl set failed");
> > > > +         return ret;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > > +                          struct v4l2_subdev_state *sd_state,
> > > > +                          struct v4l2_subdev_mbus_code_enum *code) {
> > > > + if (code->index > 0)
> > > > +         return -EINVAL;
> > > > +
> > > > + code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > > +                           struct v4l2_subdev_state *sd_state,
> > > > +                           struct v4l2_subdev_frame_size_enum *fse) {
> > > > + if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > +         return -EINVAL;
> > > > +
> > > > + if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > > +         return -EINVAL;
> > > > +
> > > > + fse->min_width = supported_modes[fse->index].width;
> > > > + fse->max_width = fse->min_width;
> > > > + fse->min_height = supported_modes[fse->index].height;
> > > > + fse->max_height = fse->min_height;
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > > +                         struct v4l2_subdev_state *state,
> > > > +                         struct v4l2_subdev_selection *sel) {
> > > > + switch (sel->target) {
> > > > + case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > + case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > +         sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > > +         sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > > +         sel->r.width = AR0234_COMMON_WIDTH;
> > > > +         sel->r.height = AR0234_COMMON_HEIGHT;
> > > > +         break;
> > > > +
> > > > + case V4L2_SEL_TGT_CROP:
> > > > +         sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > +         break;
> > > > +
> > > > + case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > +         sel->r.top = 0;
> > > > +         sel->r.left = 0;
> > > > +         sel->r.width = AR0234_NATIVE_WIDTH;
> > > > +         sel->r.height = AR0234_NATIVE_HEIGHT;
> > > > +         break;
> > > > +
> > > > + default:
> > > > +         return -EINVAL;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > > +                      struct v4l2_subdev_state *sd_state) {
> > > > + struct v4l2_subdev_format fmt = {
> > > > +         .which = V4L2_SUBDEV_FORMAT_TRY,
> > > > +         .pad = 0,
> > > > +         .format = {
> > > > +                 .code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > +                 .width = AR0234_COMMON_WIDTH,
> > > > +                 .height = AR0234_COMMON_HEIGHT,
> > > > +         },
> > > > + };
> > > > +
> > > > + ar0234_set_format(sd, sd_state, &fmt);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > > + .s_stream = ar0234_set_stream,
> > > > +};
> > > > +
> > > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > > + .set_fmt = ar0234_set_format,
> > > > + .get_fmt = v4l2_subdev_get_fmt,
> > > > + .enum_mbus_code = ar0234_enum_mbus_code,
> > > > + .enum_frame_size = ar0234_enum_frame_size,
> > > > + .get_selection = ar0234_get_selection, };
> > > > +
> > > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > > + .subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > > + .unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > > +
> > > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > > + .core = &ar0234_core_ops,
> > > > + .video = &ar0234_video_ops,
> > > > + .pad = &ar0234_pad_ops,
> > > > +};
> > > > +
> > > > +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> > > > + .link_validate = v4l2_subdev_link_validate, };
> > > > +
> > > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > > + .init_state = ar0234_init_state,
> > > > +};
> > > > +
> > > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct device
> > > > +*dev) {
> > > > + struct fwnode_handle *endpoint;
> > > > + struct v4l2_fwnode_endpoint bus_cfg = {
> > > > +         .bus_type = V4L2_MBUS_CSI2_DPHY,
> > > > + };
> > > > + int ret;
> > > > +
> > > > + endpoint =
> > > > +         fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > > +                                         FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > + if (!endpoint) {
> > > > +         dev_err(dev, "endpoint node not found");
> > > > +         return -EPROBE_DEFER;
> > > > + }
> > > > +
> > > > + ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > > + if (ret) {
> > > > +         dev_err(dev, "parsing endpoint node failed");
> > > > +         goto out_err;
> > > > + }
> > > > +
> > > > + /* Check the number of MIPI CSI2 data lanes */
> > > > + if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > > +     bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > > +         dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > > > +         goto out_err;
> > > > + }
> > > > +
> > > > + ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > > +                                bus_cfg.nr_of_link_frequencies,
> > > > +                                link_freq_menu_items,
> > > > +                                ARRAY_SIZE(link_freq_menu_items),
> > > > +                                &ar0234->link_freq_bitmap);
> > > > + if (ret)
> > > > +         goto out_err;
> > > > +
> > > > +out_err:
> > > > + v4l2_fwnode_endpoint_free(&bus_cfg);
> > > > + fwnode_handle_put(endpoint);
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > + int ret;
> > > > + u64 val;
> > > > +
> > > > + ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > > > + if (ret)
> > > > +         return ret;
> > > > +
> > > > + if (val != AR0234_CHIP_ID) {
> > > > +         dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > > +                 AR0234_CHIP_ID, val);
> > > > +         return -ENXIO;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void ar0234_remove(struct i2c_client *client) {
> > > > + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > +
> > > > + v4l2_async_unregister_subdev(&ar0234->sd);
> > > > + v4l2_subdev_cleanup(sd);
> > > > + media_entity_cleanup(&ar0234->sd.entity);
> > > > + v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > > + pm_runtime_disable(&client->dev);
> > > > + pm_runtime_set_suspended(&client->dev);
> > > > +}
> > > > +
> > > > +static int ar0234_probe(struct i2c_client *client) {
> > > > + struct device *dev = &client->dev;
> > > > + struct ar0234 *ar0234;
> > > > + struct clk *xclk;
> > > > + u32 xclk_freq;
> > > > + int ret;
> > > > +
> > > > + ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > > > + if (!ar0234)
> > > > +         return -ENOMEM;
> > > > +
> > > > + ret = ar0234_parse_fwnode(ar0234, dev);
> > > > + if (ret)
> > > > +         return ret;
> > > > +
> > > > + ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > > + if (IS_ERR(ar0234->regmap))
> > > > +         return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > > +                              "failed to init CCI");
> > > > +
> > > > + v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > > > +
> > > > + xclk = devm_clk_get(dev, NULL);
> > > > + if (IS_ERR(xclk)) {
> > > > +         if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > > +                 dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > > +         return PTR_ERR(xclk);
> > > > + }
> > > > +
> > > > + xclk_freq = clk_get_rate(xclk);
> > > > + if (xclk_freq != AR0234_XCLK_FREQ) {
> > > > +         dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > > > +         return -EINVAL;
> > > > + }
> > > > +
> > > > + /* Check module identity */
> > > > + ret = ar0234_identify_module(ar0234);
> > > > + if (ret) {
> > > > +         dev_err(dev, "failed to find sensor: %d", ret);
> > > > +         return ret;
> > > > + }
> > > > +
> > > > + ar0234->cur_mode = &supported_modes[0];
> > > > + ret = ar0234_init_controls(ar0234);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "failed to init controls: %d", ret);
> > > > +         goto probe_error_v4l2_ctrl_handler_free;
> > > > + }
> > > > +
> > > > + ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > > + ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > +                     V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > + ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > > + ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > +
> > > > + ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > + ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > > > + if (ret) {
> > > > +         dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > > +         goto probe_error_v4l2_ctrl_handler_free;
> > > > + }
> > > > +
> > > > + ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > > + ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > > + if (ret < 0) {
> > > > +         dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > > +         goto probe_error_media_entity_cleanup;
> > > > + }
> > > > +
> > > > + /*
> > > > +  * Device is already turned on by i2c-core with ACPI domain PM.
> > > > +  * Enable runtime PM and turn off the device.
> > > > +  */
> > > > + pm_runtime_set_active(&client->dev);
> > > > + pm_runtime_enable(&client->dev);
> > > > + pm_runtime_idle(&client->dev);
> > > > +
> > > > + ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > > + if (ret < 0) {
> > > > +         dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > > +                 ret);
> > > > +         goto probe_error_rpm;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +probe_error_rpm:
> > > > + pm_runtime_disable(&client->dev);
> > > > + v4l2_subdev_cleanup(&ar0234->sd);
> > > > +
> > > > +probe_error_media_entity_cleanup:
> > > > + media_entity_cleanup(&ar0234->sd.entity);
> > > > +
> > > > +probe_error_v4l2_ctrl_handler_free:
> > > > + v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > > +
> > > > + return ret;
> > > > +}
> > > > +
> > > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > > + { "INTC10C0" },
> > > > + {}
> > > > +};
> > > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > > +
> > > > +static struct i2c_driver ar0234_i2c_driver = {
> > > > + .driver = {
> > > > +         .name = "ar0234",
> > > > +         .acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > > + },
> > > > + .probe = ar0234_probe,
> > > > + .remove = ar0234_remove,
> > > > +};
> > > > +
> > > > +module_i2c_driver(ar0234_i2c_driver);
> > > > +
> > > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > > MODULE_LICENSE("GPL");
>
> --
> Regards,
>
> Laurent Pinchart
  

Hi Laurent,

Thanks for your comments

> -----Original Message-----
> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: Monday, July 1, 2024 9:57 PM
> To: Yan, Dongcheng <dongcheng.yan@intel.com>
> Cc: sakari.ailus@linux.intel.com; linux-media@vger.kernel.org;
> tomi.valkeinen@ideasonboard.com; jacopo.mondi@ideasonboard.com;
> bingbu.cao@linux.intel.com; dave.stevenson@raspberrypi.com; Li, Daxing
> <daxing.li@intel.com>; Yao, Hao <hao.yao@intel.com>
> Subject: Re: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
> 
> Hello Dongcheng,
> 
> On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> > Hi Larent,
> >
> > Sorry for that I didn't check my sent items in time, a bug of outlook
> > causes all commets after first quote to be lost. I have edited again
> > and sorry for the delay.
> 
> No worries. I'm sorry that you have to use outlook :-)
> 
> > Thanks for your review and meaningful suggestions. I have contacted
> > the vendor and optimized the code related to the register settings.
> > The response is as follows:
> >
> > On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > >
> > > Hi Dongcheng,
> > >
> > > Thank you for the patch.
> > >
> > > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > > The driver is implemented with V4L2 framework, and supports
> > > > following
> > > > features:
> > > >
> > > >     - manual exposure and analog/digital gain control
> > > >     - vblank/hblank control
> > > >     - vflip/hflip control
> > > >     - runtime PM support
> > > >     - 1280x960 at 30FPS
> > > >
> > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > > ---
> > > > v2 --> v3:
> > > >     - remove unused reg setting
> > > >     - add vflip/hflip control
> > > >     - add external clock check & lanes check
> > > >
> > > > ---
> > > >  drivers/media/i2c/Kconfig  |   11 +
> > > >  drivers/media/i2c/Makefile |    1 +
> > > >  drivers/media/i2c/ar0234.c | 1077
> > > > ++++++++++++++++++++++++++++++++++++
> > > >  3 files changed, 1089 insertions(+)  create mode 100644
> > > > drivers/media/i2c/ar0234.c
> > > >
> > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > > index c6d3ee472d81..7108d194c975 100644
> > > > --- a/drivers/media/i2c/Kconfig
> > > > +++ b/drivers/media/i2c/Kconfig
> > > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > > >  	  To compile this driver as a module, choose M here: the
> > > >  	  module will be called alvium-csi2.
> > > >
> > > > +config VIDEO_AR0234
> > > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > > +        depends on ACPI || COMPILE_TEST
> > > > +        select V4L2_CCI_I2C
> > > > +        help
> > > > +          This is a Video4Linux2 sensor driver for the ON
> Semiconductor
> > > > +          AR0234 camera.
> > > > +
> > > > +          To compile this driver as a module, choose M here: the
> > > > +          module will be called ar0234.
> > > > +
> > > >  config VIDEO_AR0521
> > > >  	tristate "ON Semiconductor AR0521 sensor support"
> > > >  	help
> > > > diff --git a/drivers/media/i2c/Makefile
> > > > b/drivers/media/i2c/Makefile index dfbe6448b549..57b4f62106d9
> > > > 100644
> > > > --- a/drivers/media/i2c/Makefile
> > > > +++ b/drivers/media/i2c/Makefile
> > > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o diff --git
> > > > a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c new file
> > > > mode 100644 index 000000000000..80fe5ffd1c64
> > > > --- /dev/null
> > > > +++ b/drivers/media/i2c/ar0234.c
> > > > @@ -0,0 +1,1077 @@
> > > > +// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 - 2024
> > > > +Intel Corporation.
> > > > +
> > > > +#include <linux/acpi.h>
> > > > +#include <linux/clk.h>
> > > > +#include <linux/delay.h>
> > > > +#include <linux/i2c.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/pm_runtime.h>
> > > > +#include <asm/unaligned.h>
> > > > +
> > > > +#include <media/v4l2-cci.h>
> > > > +#include <media/v4l2-ctrls.h>
> > > > +#include <media/v4l2-event.h>
> > > > +#include <media/v4l2-device.h>
> > > > +#include <media/v4l2-fwnode.h>
> > > > +
> > > > +/* Chip ID */
> > > > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > > > +#define AR0234_CHIP_ID			0x0a56
> > > > +
> > > > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > > > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > > > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > > > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > > > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > > > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > > > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > > > +
> > > > +#define AR0234_EXPOSURE_MIN		0
> > > > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > > > +#define AR0234_EXPOSURE_STEP		1
> > > > +
> > > > +#define AR0234_ANALOG_GAIN_MIN		0
> > > > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > > > +#define AR0234_ANALOG_GAIN_STEP		1
> > > > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > > > +
> > > > +#define AR0234_GLOBAL_GAIN_MIN		0
> > > > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > > > +#define AR0234_GLOBAL_GAIN_STEP		1
> > > > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > > > +
> > > > +#define AR0234_NATIVE_WIDTH		1920
> > > > +#define AR0234_NATIVE_HEIGHT		1080
> > > > +#define AR0234_COMMON_WIDTH		1280
> > > > +#define AR0234_COMMON_HEIGHT		960
> > > > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > > > +#define AR0234_PIXEL_ARRAY_TOP		60
> > > > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > > > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > > > +
> > > > +#define AR0234_VTS_DEFAULT		0x04c4
> > > > +#define AR0234_VTS_MAX			0xffff
> > > > +#define AR0234_HTS_DEFAULT		0x04c4
> > > > +#define AR0234_PPL_DEFAULT		3498
> > > > +
> > > > +#define AR0234_MODE_RESET		0x00d9
> > > > +#define AR0234_MODE_STANDBY		0x2058
> > > > +#define AR0234_MODE_STREAMING		0x205c
> > > > +
> > > > +#define AR0234_PIXEL_RATE		128000000ULL
> > > > +#define AR0234_XCLK_FREQ		19200000ULL
> > > > +
> > > > +#define AR0234_TEST_PATTERN_DISABLE	0
> > > > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > > > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > > > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > > > +#define AR0234_TEST_PATTERN_WALKING	256
> > > > +
> > > > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > > > +
> > > > +struct ar0234_reg_list {
> > > > +	u32 num_of_regs;
> > > > +	const struct cci_reg_sequence *regs; };
> > > > +
> > > > +struct ar0234_mode {
> > > > +	u32 width;
> > > > +	u32 height;
> > > > +	u32 hts;
> > > > +	u32 vts_def;
> > > > +	u32 code;
> > > > +	/* Sensor register settings for this mode */
> > > > +	const struct ar0234_reg_list reg_list; };
> > > > +
> > > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > > +	{ CCI_REG16(0x3f4c), 0x121f },
> > > > +	{ CCI_REG16(0x3f4e), 0x121f },
> > > > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > > > +	{ CCI_REG16(0x31e0), 0x0003 },
> > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > +	/* R0x3088 specify the sequencer RAM access address. */
> > > > +	{ CCI_REG16(0x3088), 0x8000 },
> > > > +	/* R0x3086 write the sequencer RAM. */
> > > > +	{ CCI_REG16(0x3086), 0xc1ae },
> > > > +	{ CCI_REG16(0x3086), 0x327f },
> > > > +	{ CCI_REG16(0x3086), 0x5780 },
> > > > +	{ CCI_REG16(0x3086), 0x272f },
> > > > +	{ CCI_REG16(0x3086), 0x7416 },
> > >
> > > Storing the sequencer data in this table wastes lots of memory and CPU
> cycles.
> > > Please move the data out to a
> > >
> > > static const u16 ar0234_sequencer[] = {
> > > 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > > 	...
> > > };
> > >
> > > table, and program it with
> > >
> > > 	/* Program the sequencer. */
> > > 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > > 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > > 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > > 			  ar0234_sequencer[i], &ret);
> > >
> > > And please define macros for the sequencer access registers 0x3086
> > > and 0x3088, as well as for the bits of the 0x3088 register.
> > >
> > > [snip]
> >
> > Through communication with the vendor, we learned that this is a patch
> > (writing to the sequencer) used to optimize the sensor's performance.
> > It is not critical for the driver's normal operation. Therefore, I
> > will remove this patch directly.
> 
> I'm fine dropping it or keeping it, it's up to you. If it improves the image quality
> I think it's useful. my only concern is that storing the register address in every
> entry wastes space. With an optimized version that only stores the data, I'm
> fine having the data in the driver.
> 

You concern is sound, moving the data to a list is a good idea to avoid too much stress, how about upstreaming the basic driver now and to upstream this optimized patch separately as vendor may fix them in firmware.

> > > > +	{ CCI_REG16(0x302a), 0x0005 },
> > > > +	{ CCI_REG16(0x302c), 0x0001 },
> > > > +	{ CCI_REG16(0x302e), 0x0003 },
> > > > +	{ CCI_REG16(0x3030), 0x0032 },
> > > > +	{ CCI_REG16(0x3036), 0x000a },
> > > > +	{ CCI_REG16(0x3038), 0x0001 },
> > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > +	{ CCI_REG16(0x31b0), 0x0082 },
> > > > +	{ CCI_REG16(0x31b2), 0x005c },
> > > > +	{ CCI_REG16(0x31b4), 0x5248 },
> > > > +	{ CCI_REG16(0x31b6), 0x3257 },
> > > > +	{ CCI_REG16(0x31b8), 0x904b },
> > > > +	{ CCI_REG16(0x31ba), 0x030b },
> > > > +	{ CCI_REG16(0x31bc), 0x8e09 },
> > > > +	{ CCI_REG16(0x3354), 0x002b },
> > > > +	{ CCI_REG16(0x31d0), 0x0000 },
> > > > +	{ CCI_REG16(0x31ae), 0x0204 },
> > > > +	{ CCI_REG16(0x3002), 0x0080 },
> > > > +	{ CCI_REG16(0x3004), 0x0148 },
> > > > +	{ CCI_REG16(0x3006), 0x043f },
> > > > +	{ CCI_REG16(0x3008), 0x0647 },
> > > > +	{ CCI_REG16(0x3064), 0x1802 },
> > > > +	{ CCI_REG16(0x300a), 0x04c4 },
> > > > +	{ CCI_REG16(0x300c), 0x04c4 },
> > > > +	{ CCI_REG16(0x30a2), 0x0001 },
> > > > +	{ CCI_REG16(0x30a6), 0x0001 },
> > > > +	{ CCI_REG16(0x3012), 0x010c },
> > > > +	{ CCI_REG16(0x3786), 0x0006 },
> > > > +	{ CCI_REG16(0x31ae), 0x0202 },
> > > > +	{ CCI_REG16(0x3088), 0x8050 },
> > > > +	{ CCI_REG16(0x3086), 0x9237 },
> > >
> > > This can stay here if it needs to be programmed separately from the
> > > rest of the sequencer data, but please use macros to replace the
> > > hardcoded register addresses, and the value of the 0x3088 register.
> >
> > I will annotate each of their usages here. These are two recommended
> > common settings provided by the vendor.
> >
> > > > +	{ CCI_REG16(0x3044), 0x0410 },
> > > > +	{ CCI_REG16(0x3094), 0x03d4 },
> > > > +	{ CCI_REG16(0x3096), 0x0280 },
> > > > +	{ CCI_REG16(0x30ba), 0x7606 },
> > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > +	{ CCI_REG16(0x30ba), 0x7600 },
> > > > +	{ CCI_REG16(0x30fe), 0x002a },
> > > > +	{ CCI_REG16(0x31de), 0x0410 },
> > > > +	{ CCI_REG16(0x3ed6), 0x1435 },
> > > > +	{ CCI_REG16(0x3ed8), 0x9865 },
> > > > +	{ CCI_REG16(0x3eda), 0x7698 },
> > > > +	{ CCI_REG16(0x3edc), 0x99ff },
> > > > +	{ CCI_REG16(0x3ee2), 0xbb88 },
> > > > +	{ CCI_REG16(0x3ee4), 0x8836 },
> > > > +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> > > > +	{ CCI_REG16(0x3ef2), 0x0000 },
> > > > +	{ CCI_REG16(0x3ef8), 0x6166 },
> > > > +	{ CCI_REG16(0x3efa), 0x3333 },
> > > > +	{ CCI_REG16(0x3efc), 0x6634 },
> > > > +	{ CCI_REG16(0x3088), 0x81ba },
> > > > +	{ CCI_REG16(0x3086), 0x3d02 },
> > >
> > > Same here.
> > >
> > > > +	{ CCI_REG16(0x3276), 0x05dc },
> > > > +	{ CCI_REG16(0x3f00), 0x9d05 },
> > > > +	{ CCI_REG16(0x3ed2), 0xfa86 },
> > > > +	{ CCI_REG16(0x3eee), 0xa4fe },
> > > > +	{ CCI_REG16(0x3ecc), 0x6e42 },
> > > > +	{ CCI_REG16(0x3ecc), 0x0e42 },
> > > > +	{ CCI_REG16(0x3eec), 0x0c0c },
> > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > +	{ CCI_REG16(0x3180), 0xc24f },
> > > > +	{ CCI_REG16(0x3102), 0x5000 },
> > > > +	{ CCI_REG16(0x3060), 0x000d },
> > > > +	{ CCI_REG16(0x3ed0), 0xff44 },
> > > > +	{ CCI_REG16(0x3ed2), 0xaa86 },
> > > > +	{ CCI_REG16(0x3ed4), 0x031f },
> > > > +	{ CCI_REG16(0x3eee), 0xa4aa },
> > >
> > > Among all the registers above, at least the following need a macro
> > > for the register name and register bits:
> > >
> > > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a,
> > > 0x302c, 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2,
> > > 0x30a6, 0x30b0, 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2,
> > > 0x31b4, 0x31b6, 0x31b8, 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > > 0x3786
> > >
> > > Some of them should also be handled programmatically, not hardcoded.
> >
> > Thanks for your comments, I replace all with macros now.
> >
> > > Ideally, the following registers should also be documented with macros:
> > >
> > > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> >
> > Most of the registers you listed cannot be found in the spec, and they
> > work together within the recommended common settings provided by the
> > vendor. Because the functions of these registers are not singular,
> > defining macros not specified in the spec can cause misunderstandings.
> > I add necessary comments to make code more readable.
> 
> OK I'm fine with that.
> 
> > > 0x30ba, in particular, varies depending on the analog gain and pixel
> > > clock, so it needs to be handled programmatically.
> >
> > 0x30BA is independent of analog gain and pixel clock.
> 
> Doesn't table 26 in the developer guide show otherwise (for bits [2:0] at
> least) ?
> 

Maybe what I said confused you, I mean that they can achieve better gain quality when combined, it fixed to 6 according to vendor's register setting, also seen in Dave's comments. I think it can be a TODO if more pixel clk is used later.

> > Under the current pixel clock settings, 0x30BA is fixed in spec and
> > set to 0x7606.
> 
> Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2 MHz.
> That's a pretty unusual value. Given that the sensor uses a quite standard PLL
> model, I think you can use the ccs-pll helper to calculate the PLL parameters
> dynamically at runtime. See for instance
> https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.pinchar
> t@ideasonboard.com/
> for an example of how to do so, for a sensor that has a very similar (if not
> identical) PLL topology. Sakari can also help if you have issues with the ccs-pll
> helper.
> 

As Dave mentioned, 19.2MHz is the XCLK we used all along. We currently have no plans to use other XCLK, as using ccs-pll is not so essential for this sensor. Of course, I have studied the instance you provided carefully, and if necessary, I am willing to add this feature.

Thanks,
Dongcheng

> > It would be better to configure it to the recommended value but not
> > crucial (the vendor did not provide a clear explanation whether this
> > is for image quality or performance). handling it should be considered
> > an optimization patch if using more pxlclk configurations in the
> > future.
> >
> > > > +};
> > > > +
> > > > +static const char * const ar0234_test_pattern_menu[] = {
> > > > +	"Disabled",
> > > > +	"Color Bars",
> > > > +	"Solid Color",
> > > > +	"Grey Color Bars",
> > > > +	"Walking 1s",
> > > > +};
> > > > +
> > > > +static const int ar0234_test_pattern_val[] = {
> > > > +	AR0234_TEST_PATTERN_DISABLE,
> > > > +	AR0234_TEST_PATTERN_COLOR_BARS,
> > > > +	AR0234_TEST_PATTERN_SOLID_COLOR,
> > > > +	AR0234_TEST_PATTERN_GREY_COLOR,
> > > > +	AR0234_TEST_PATTERN_WALKING,
> > > > +};
> > > > +
> > > > +static const s64 link_freq_menu_items[] = {
> > > > +	360000000ULL,
> > > > +};
> > > > +
> > > > +static const struct ar0234_mode supported_modes[] = {
> > > > +	{
> > > > +		.width = AR0234_COMMON_WIDTH,
> > > > +		.height = AR0234_COMMON_HEIGHT,
> > > > +		.hts = AR0234_HTS_DEFAULT,
> > > > +		.vts_def = AR0234_VTS_DEFAULT,
> > > > +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > +		.reg_list = {
> > > > +			.num_of_regs =
> ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > > +			.regs = mode_1280x960_10bit_2lane,
> > > > +		},
> > > > +	},
> > > > +};
> > > > +
> > > > +struct ar0234 {
> > > > +	struct v4l2_subdev sd;
> > > > +	struct media_pad pad;
> > > > +	struct v4l2_ctrl_handler ctrl_handler;
> > > > +
> > > > +	/* V4L2 Controls */
> > > > +	struct v4l2_ctrl *link_freq;
> > > > +	struct v4l2_ctrl *exposure;
> > > > +	struct v4l2_ctrl *hblank;
> > > > +	struct v4l2_ctrl *vblank;
> > > > +	struct v4l2_ctrl *vflip;
> > > > +	struct v4l2_ctrl *hflip;
> > > > +	struct regmap *regmap;
> > > > +	unsigned long link_freq_bitmap;
> > > > +	const struct ar0234_mode *cur_mode; };
> > > > +
> > > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > > +	struct ar0234 *ar0234 =
> > > > +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +	s64 exposure_max, exposure_def;
> > > > +	struct v4l2_subdev_state *state;
> > > > +	const struct v4l2_mbus_framefmt *format;
> > > > +	int ret;
> > > > +
> > > > +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > > +	format = v4l2_subdev_state_get_format(state, 0);
> > > > +
> > > > +	/* Propagate change of current control to all related controls */
> > > > +	if (ctrl->id == V4L2_CID_VBLANK) {
> > > > +		/* Update max exposure while meeting expected vblanking */
> > > > +		exposure_max = format->height + ctrl->val -
> > > > +			       AR0234_EXPOSURE_MAX_MARGIN;
> > > > +		exposure_def = format->height -
> AR0234_EXPOSURE_MAX_MARGIN;
> > > > +		__v4l2_ctrl_modify_range(ar0234->exposure,
> > > > +					 ar0234->exposure->minimum,
> > > > +					 exposure_max, ar0234->exposure->step,
> > > > +					 exposure_def);
> > > > +	}
> > > > +
> > > > +	/* V4L2 controls values will be applied only when power is already
> up */
> > > > +	if (!pm_runtime_get_if_in_use(&client->dev))
> > > > +		return 0;
> > > > +
> > > > +	switch (ctrl->id) {
> > > > +	case V4L2_CID_ANALOGUE_GAIN:
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > > > +				ctrl->val, NULL);
> > > > +		break;
> > > > +
> > > > +	case V4L2_CID_DIGITAL_GAIN:
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > > > +				ctrl->val, NULL);
> > > > +		break;
> > > > +
> > > > +	case V4L2_CID_EXPOSURE:
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > > +				ctrl->val, NULL);
> > > > +		break;
> > > > +
> > > > +	case V4L2_CID_VBLANK:
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > > +				ar0234->cur_mode->height + ctrl->val, NULL);
> > > > +		break;
> > > > +
> > > > +	case V4L2_CID_HFLIP:
> > > > +	case V4L2_CID_VFLIP:
> > > > +		u64 reg;
> > > > +
> > > > +		ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > +			       &reg, NULL);
> > > > +		if (ret)
> > > > +			break;
> > > > +
> > > > +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > > +			 AR0234_ORIENTATION_VFLIP);
> > > > +		if (ar0234->hflip->val)
> > > > +			reg |= AR0234_ORIENTATION_HFLIP;
> > > > +		if (ar0234->vflip->val)
> > > > +			reg |= AR0234_ORIENTATION_VFLIP;
> > > > +
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > +				reg, NULL);
> > > > +		break;
> > > > +
> > > > +	case V4L2_CID_TEST_PATTERN:
> > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > > > +				ar0234_test_pattern_val[ctrl->val], NULL);
> > > > +		break;
> > > > +
> > > > +	default:
> > > > +		ret = -EINVAL;
> > > > +		break;
> > > > +	}
> > > > +
> > > > +	pm_runtime_put(&client->dev);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > > +	.s_ctrl = ar0234_set_ctrl,
> > > > +};
> > > > +
> > > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +	struct v4l2_fwnode_device_properties props;
> > > > +	struct v4l2_ctrl_handler *ctrl_hdlr;
> > > > +	s64 exposure_max, vblank_max, vblank_def, hblank;
> > > > +	u32 link_freq_size;
> > > > +	int ret;
> > > > +
> > > > +	ctrl_hdlr = &ar0234->ctrl_handler;
> > > > +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > > +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > > +						   &ar0234_ctrl_ops,
> > > > +						   V4L2_CID_LINK_FREQ,
> > > > +						   link_freq_size, 0,
> > > > +						   link_freq_menu_items);
> > > > +	if (ar0234->link_freq)
> > > > +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > +
> > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > V4L2_CID_ANALOGUE_GAIN,
> > > > +			  AR0234_ANALOG_GAIN_MIN,
> AR0234_ANALOG_GAIN_MAX,
> > > > +			  AR0234_ANALOG_GAIN_STEP,
> > > AR0234_ANALOG_GAIN_DEFAULT);
> > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_DIGITAL_GAIN,
> > > > +			  AR0234_GLOBAL_GAIN_MIN,
> AR0234_GLOBAL_GAIN_MAX,
> > > > +			  AR0234_GLOBAL_GAIN_STEP,
> > > AR0234_GLOBAL_GAIN_DEFAULT);
> > > > +
> > > > +	exposure_max = ar0234->cur_mode->vts_def -
> > > AR0234_EXPOSURE_MAX_MARGIN;
> > > > +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					     V4L2_CID_EXPOSURE,
> > > > +					     AR0234_EXPOSURE_MIN, exposure_max,
> > > > +					     AR0234_EXPOSURE_STEP,
> > > > +					     exposure_max);
> > > > +
> > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_PIXEL_RATE,
> > > > +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > > +			  AR0234_PIXEL_RATE);
> > > > +
> > > > +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > > +	vblank_def = ar0234->cur_mode->vts_def -
> ar0234->cur_mode->height;
> > > > +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > > +					   vblank_def);
> > > > +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > > +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> > > > +					   hblank);
> > > > +	if (ar0234->hblank)
> > > > +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > +
> > > > +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > > +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > > +
> > > > +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +				     V4L2_CID_TEST_PATTERN,
> > > > +				     ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > > > +				     0, 0, ar0234_test_pattern_menu);
> > > > +
> > > > +	if (ctrl_hdlr->error)
> > > > +		return ctrl_hdlr->error;
> > > > +
> > > > +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > +					      &props);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static void ar0234_update_pad_format(const struct ar0234_mode
> *mode,
> > > > +				     struct v4l2_mbus_framefmt *fmt) {
> > > > +	fmt->width = mode->width;
> > > > +	fmt->height = mode->height;
> > > > +	fmt->code = mode->code;
> > > > +	fmt->field = V4L2_FIELD_NONE;
> > > > +}
> > > > +
> > > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +	const struct ar0234_reg_list *reg_list;
> > > > +	int ret;
> > > > +
> > > > +	ret = pm_runtime_resume_and_get(&client->dev);
> > > > +	if (ret < 0)
> > > > +		return ret;
> > > > +
> > > > +	/*
> > > > +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > > +	 * the frame being generated will be truncated.
> > > > +	 */
> > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +			AR0234_MODE_RESET, NULL);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "failed to reset");
> > > > +		goto err_rpm_put;
> > > > +	}
> > > > +
> > > > +	usleep_range(1000, 1500);
> > > > +
> > > > +	reg_list = &ar0234->cur_mode->reg_list;
> > > > +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > > +				  reg_list->num_of_regs, NULL);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "failed to set mode");
> > > > +		goto err_rpm_put;
> > > > +	}
> > > > +
> > > > +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > > +	if (ret)
> > > > +		goto err_rpm_put;
> > > > +
> > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +			AR0234_MODE_STREAMING, NULL);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "failed to start stream");
> > > > +		goto err_rpm_put;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +
> > > > +err_rpm_put:
> > > > +	pm_runtime_put(&client->dev);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > > +	int ret;
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +
> > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > +			AR0234_MODE_STANDBY, NULL);
> > > > +	if (ret < 0)
> > > > +		dev_err(&client->dev, "failed to stop stream");
> > > > +
> > > > +	pm_runtime_put(&client->dev);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > +	struct v4l2_subdev_state *state;
> > > > +	int ret = 0;
> > > > +
> > > > +	state = v4l2_subdev_lock_and_get_active_state(sd);
> > > > +
> > > > +	if (enable)
> > > > +		ret = ar0234_start_streaming(ar0234);
> > > > +	else
> > > > +		ret = ar0234_stop_streaming(ar0234);
> > > > +
> > > > +	/* vflip and hflip cannot change during streaming */
> > > > +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> > > > +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> > > > +	v4l2_subdev_unlock_state(state);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > > +			     struct v4l2_subdev_state *sd_state,
> > > > +			     struct v4l2_subdev_format *fmt) {
> > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +	struct v4l2_rect *crop;
> > > > +	const struct ar0234_mode *mode;
> > > > +	s64 hblank;
> > > > +	int ret;
> > > > +
> > > > +	mode = v4l2_find_nearest_size(supported_modes,
> > > > +				      ARRAY_SIZE(supported_modes),
> > > > +				      width, height,
> > > > +				      fmt->format.width,
> > > > +				      fmt->format.height);
> > > > +
> > > > +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > > +	crop->width = mode->width;
> > > > +	crop->height = mode->height;
> > > > +
> > > > +	ar0234_update_pad_format(mode, &fmt->format);
> > > > +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > > > +
> > > > +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > > +		return 0;
> > > > +
> > > > +	ar0234->cur_mode = mode;
> > > > +
> > > > +	hblank = AR0234_PPL_DEFAULT - mode->width;
> > > > +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > > > +				       1, hblank);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "HB ctrl range update failed");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	/* Update limits and set FPS to default */
> > > > +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > > +				       AR0234_VTS_MAX - mode->height, 1,
> > > > +				       mode->vts_def - mode->height);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "VB ctrl range update failed");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def -
> mode->height);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "VB ctrl set failed");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > > +				 struct v4l2_subdev_state *sd_state,
> > > > +				 struct v4l2_subdev_mbus_code_enum *code) {
> > > > +	if (code->index > 0)
> > > > +		return -EINVAL;
> > > > +
> > > > +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > > +				  struct v4l2_subdev_state *sd_state,
> > > > +				  struct v4l2_subdev_frame_size_enum *fse) {
> > > > +	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > +		return -EINVAL;
> > > > +
> > > > +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > > +		return -EINVAL;
> > > > +
> > > > +	fse->min_width = supported_modes[fse->index].width;
> > > > +	fse->max_width = fse->min_width;
> > > > +	fse->min_height = supported_modes[fse->index].height;
> > > > +	fse->max_height = fse->min_height;
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > > +				struct v4l2_subdev_state *state,
> > > > +				struct v4l2_subdev_selection *sel) {
> > > > +	switch (sel->target) {
> > > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > +	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > > +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > > +		sel->r.width = AR0234_COMMON_WIDTH;
> > > > +		sel->r.height = AR0234_COMMON_HEIGHT;
> > > > +		break;
> > > > +
> > > > +	case V4L2_SEL_TGT_CROP:
> > > > +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > +		break;
> > > > +
> > > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > +		sel->r.top = 0;
> > > > +		sel->r.left = 0;
> > > > +		sel->r.width = AR0234_NATIVE_WIDTH;
> > > > +		sel->r.height = AR0234_NATIVE_HEIGHT;
> > > > +		break;
> > > > +
> > > > +	default:
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > > +			     struct v4l2_subdev_state *sd_state) {
> > > > +	struct v4l2_subdev_format fmt = {
> > > > +		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > > +		.pad = 0,
> > > > +		.format = {
> > > > +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > +			.width = AR0234_COMMON_WIDTH,
> > > > +			.height = AR0234_COMMON_HEIGHT,
> > > > +		},
> > > > +	};
> > > > +
> > > > +	ar0234_set_format(sd, sd_state, &fmt);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > > +	.s_stream = ar0234_set_stream,
> > > > +};
> > > > +
> > > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > > +	.set_fmt = ar0234_set_format,
> > > > +	.get_fmt = v4l2_subdev_get_fmt,
> > > > +	.enum_mbus_code = ar0234_enum_mbus_code,
> > > > +	.enum_frame_size = ar0234_enum_frame_size,
> > > > +	.get_selection = ar0234_get_selection, };
> > > > +
> > > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > > +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > > +	.unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > > +
> > > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > > +	.core = &ar0234_core_ops,
> > > > +	.video = &ar0234_video_ops,
> > > > +	.pad = &ar0234_pad_ops,
> > > > +};
> > > > +
> > > > +static const struct media_entity_operations ar0234_subdev_entity_ops
> = {
> > > > +	.link_validate = v4l2_subdev_link_validate, };
> > > > +
> > > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > > +	.init_state = ar0234_init_state, };
> > > > +
> > > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct
> > > > +device
> > > > +*dev) {
> > > > +	struct fwnode_handle *endpoint;
> > > > +	struct v4l2_fwnode_endpoint bus_cfg = {
> > > > +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> > > > +	};
> > > > +	int ret;
> > > > +
> > > > +	endpoint =
> > > > +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > > +						FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > +	if (!endpoint) {
> > > > +		dev_err(dev, "endpoint node not found");
> > > > +		return -EPROBE_DEFER;
> > > > +	}
> > > > +
> > > > +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > > +	if (ret) {
> > > > +		dev_err(dev, "parsing endpoint node failed");
> > > > +		goto out_err;
> > > > +	}
> > > > +
> > > > +	/* Check the number of MIPI CSI2 data lanes */
> > > > +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > > +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > > +		dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > > > +		goto out_err;
> > > > +	}
> > > > +
> > > > +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > > +				       bus_cfg.nr_of_link_frequencies,
> > > > +				       link_freq_menu_items,
> > > > +				       ARRAY_SIZE(link_freq_menu_items),
> > > > +				       &ar0234->link_freq_bitmap);
> > > > +	if (ret)
> > > > +		goto out_err;
> > > > +
> > > > +out_err:
> > > > +	v4l2_fwnode_endpoint_free(&bus_cfg);
> > > > +	fwnode_handle_put(endpoint);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > +	int ret;
> > > > +	u64 val;
> > > > +
> > > > +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	if (val != AR0234_CHIP_ID) {
> > > > +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > > +			AR0234_CHIP_ID, val);
> > > > +		return -ENXIO;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static void ar0234_remove(struct i2c_client *client) {
> > > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > +
> > > > +	v4l2_async_unregister_subdev(&ar0234->sd);
> > > > +	v4l2_subdev_cleanup(sd);
> > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > > +	pm_runtime_disable(&client->dev);
> > > > +	pm_runtime_set_suspended(&client->dev);
> > > > +}
> > > > +
> > > > +static int ar0234_probe(struct i2c_client *client) {
> > > > +	struct device *dev = &client->dev;
> > > > +	struct ar0234 *ar0234;
> > > > +	struct clk *xclk;
> > > > +	u32 xclk_freq;
> > > > +	int ret;
> > > > +
> > > > +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > > > +	if (!ar0234)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	ret = ar0234_parse_fwnode(ar0234, dev);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > > +	if (IS_ERR(ar0234->regmap))
> > > > +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > > +				     "failed to init CCI");
> > > > +
> > > > +	v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > > > +
> > > > +	xclk = devm_clk_get(dev, NULL);
> > > > +	if (IS_ERR(xclk)) {
> > > > +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > > +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > > +		return PTR_ERR(xclk);
> > > > +	}
> > > > +
> > > > +	xclk_freq = clk_get_rate(xclk);
> > > > +	if (xclk_freq != AR0234_XCLK_FREQ) {
> > > > +		dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	/* Check module identity */
> > > > +	ret = ar0234_identify_module(ar0234);
> > > > +	if (ret) {
> > > > +		dev_err(dev, "failed to find sensor: %d", ret);
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	ar0234->cur_mode = &supported_modes[0];
> > > > +	ret = ar0234_init_controls(ar0234);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "failed to init controls: %d", ret);
> > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > +	}
> > > > +
> > > > +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > > +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > > +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > +
> > > > +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > +	ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > > > +	if (ret) {
> > > > +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > +	}
> > > > +
> > > > +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > > +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > > +	if (ret < 0) {
> > > > +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > > +		goto probe_error_media_entity_cleanup;
> > > > +	}
> > > > +
> > > > +	/*
> > > > +	 * Device is already turned on by i2c-core with ACPI domain PM.
> > > > +	 * Enable runtime PM and turn off the device.
> > > > +	 */
> > > > +	pm_runtime_set_active(&client->dev);
> > > > +	pm_runtime_enable(&client->dev);
> > > > +	pm_runtime_idle(&client->dev);
> > > > +
> > > > +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > > +	if (ret < 0) {
> > > > +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > > +			ret);
> > > > +		goto probe_error_rpm;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +probe_error_rpm:
> > > > +	pm_runtime_disable(&client->dev);
> > > > +	v4l2_subdev_cleanup(&ar0234->sd);
> > > > +
> > > > +probe_error_media_entity_cleanup:
> > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > +
> > > > +probe_error_v4l2_ctrl_handler_free:
> > > > +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > > +	{ "INTC10C0" },
> > > > +	{}
> > > > +};
> > > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > > +
> > > > +static struct i2c_driver ar0234_i2c_driver = {
> > > > +	.driver = {
> > > > +		.name = "ar0234",
> > > > +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > > +	},
> > > > +	.probe = ar0234_probe,
> > > > +	.remove = ar0234_remove,
> > > > +};
> > > > +
> > > > +module_i2c_driver(ar0234_i2c_driver);
> > > > +
> > > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > > MODULE_LICENSE("GPL");
> 
> --
> Regards,
> 
> Laurent Pinchart
  

Hi Dave,

On Mon, Jul 01, 2024 at 03:18:34PM +0100, Dave Stevenson wrote:
> On Mon, 1 Jul 2024 at 14:57, Laurent Pinchart wrote:
> > On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> > > Hi Larent,
> > >
> > > Sorry for that I didn't check my sent items in time, a bug of outlook
> > > causes all commets after first quote to be lost. I have edited again
> > > and sorry for the delay.
> >
> > No worries. I'm sorry that you have to use outlook :-)
> >
> > > Thanks for your review and meaningful suggestions. I have contacted
> > > the vendor and optimized the code related to the register settings.
> > > The response is as follows:
> > >
> > > On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > > >
> > > > Hi Dongcheng,
> > > >
> > > > Thank you for the patch.
> > > >
> > > > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > > > The driver is implemented with V4L2 framework, and supports following
> > > > > features:
> > > > >
> > > > >     - manual exposure and analog/digital gain control
> > > > >     - vblank/hblank control
> > > > >     - vflip/hflip control
> > > > >     - runtime PM support
> > > > >     - 1280x960 at 30FPS
> > > > >
> > > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > > > ---
> > > > > v2 --> v3:
> > > > >     - remove unused reg setting
> > > > >     - add vflip/hflip control
> > > > >     - add external clock check & lanes check
> > > > >
> > > > > ---
> > > > >  drivers/media/i2c/Kconfig  |   11 +
> > > > >  drivers/media/i2c/Makefile |    1 +
> > > > >  drivers/media/i2c/ar0234.c | 1077 ++++++++++++++++++++++++++++++++++++
> > > > >  3 files changed, 1089 insertions(+)
> > > > >  create mode 100644 drivers/media/i2c/ar0234.c
> > > > >
> > > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > > > index c6d3ee472d81..7108d194c975 100644
> > > > > --- a/drivers/media/i2c/Kconfig
> > > > > +++ b/drivers/media/i2c/Kconfig
> > > > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > > > >     To compile this driver as a module, choose M here: the
> > > > >     module will be called alvium-csi2.
> > > > >
> > > > > +config VIDEO_AR0234
> > > > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > > > +        depends on ACPI || COMPILE_TEST
> > > > > +        select V4L2_CCI_I2C
> > > > > +        help
> > > > > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > > > > +          AR0234 camera.
> > > > > +
> > > > > +          To compile this driver as a module, choose M here: the
> > > > > +          module will be called ar0234.
> > > > > +
> > > > >  config VIDEO_AR0521
> > > > >   tristate "ON Semiconductor AR0521 sensor support"
> > > > >   help
> > > > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> > > > > index dfbe6448b549..57b4f62106d9 100644
> > > > > --- a/drivers/media/i2c/Makefile
> > > > > +++ b/drivers/media/i2c/Makefile
> > > > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > > > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > > > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > > > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > > > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > > > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > > > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o
> > > > > diff --git a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c
> > > > > new file mode 100644 index 000000000000..80fe5ffd1c64
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/i2c/ar0234.c
> > > > > @@ -0,0 +1,1077 @@
> > > > > +// SPDX-License-Identifier: GPL-2.0
> > > > > +// Copyright (c) 2019 - 2024 Intel Corporation.
> > > > > +
> > > > > +#include <linux/acpi.h>
> > > > > +#include <linux/clk.h>
> > > > > +#include <linux/delay.h>
> > > > > +#include <linux/i2c.h>
> > > > > +#include <linux/module.h>
> > > > > +#include <linux/pm_runtime.h>
> > > > > +#include <asm/unaligned.h>
> > > > > +
> > > > > +#include <media/v4l2-cci.h>
> > > > > +#include <media/v4l2-ctrls.h>
> > > > > +#include <media/v4l2-event.h>
> > > > > +#include <media/v4l2-device.h>
> > > > > +#include <media/v4l2-fwnode.h>
> > > > > +
> > > > > +/* Chip ID */
> > > > > +#define AR0234_REG_CHIP_ID               CCI_REG16(0x3000)
> > > > > +#define AR0234_CHIP_ID                   0x0a56
> > > > > +
> > > > > +#define AR0234_REG_MODE_SELECT           CCI_REG16(0x301a)
> > > > > +#define AR0234_REG_VTS                   CCI_REG16(0x300a)
> > > > > +#define AR0234_REG_EXPOSURE              CCI_REG16(0x3012)
> > > > > +#define AR0234_REG_ANALOG_GAIN           CCI_REG16(0x3060)
> > > > > +#define AR0234_REG_GLOBAL_GAIN           CCI_REG16(0x305e)
> > > > > +#define AR0234_REG_ORIENTATION           CCI_REG16(0x3040)
> > > > > +#define AR0234_REG_TEST_PATTERN          CCI_REG16(0x0600)
> > > > > +
> > > > > +#define AR0234_EXPOSURE_MIN              0
> > > > > +#define AR0234_EXPOSURE_MAX_MARGIN       80
> > > > > +#define AR0234_EXPOSURE_STEP             1
> > > > > +
> > > > > +#define AR0234_ANALOG_GAIN_MIN           0
> > > > > +#define AR0234_ANALOG_GAIN_MAX           0x7f
> > > > > +#define AR0234_ANALOG_GAIN_STEP          1
> > > > > +#define AR0234_ANALOG_GAIN_DEFAULT       0xe
> > > > > +
> > > > > +#define AR0234_GLOBAL_GAIN_MIN           0
> > > > > +#define AR0234_GLOBAL_GAIN_MAX           0x7ff
> > > > > +#define AR0234_GLOBAL_GAIN_STEP          1
> > > > > +#define AR0234_GLOBAL_GAIN_DEFAULT       0x80
> > > > > +
> > > > > +#define AR0234_NATIVE_WIDTH              1920
> > > > > +#define AR0234_NATIVE_HEIGHT             1080
> > > > > +#define AR0234_COMMON_WIDTH              1280
> > > > > +#define AR0234_COMMON_HEIGHT             960
> > > > > +#define AR0234_PIXEL_ARRAY_LEFT          320
> > > > > +#define AR0234_PIXEL_ARRAY_TOP           60
> > > > > +#define AR0234_ORIENTATION_HFLIP BIT(14)
> > > > > +#define AR0234_ORIENTATION_VFLIP BIT(15)
> > > > > +
> > > > > +#define AR0234_VTS_DEFAULT               0x04c4
> > > > > +#define AR0234_VTS_MAX                   0xffff
> > > > > +#define AR0234_HTS_DEFAULT               0x04c4
> > > > > +#define AR0234_PPL_DEFAULT               3498
> > > > > +
> > > > > +#define AR0234_MODE_RESET                0x00d9
> > > > > +#define AR0234_MODE_STANDBY              0x2058
> > > > > +#define AR0234_MODE_STREAMING            0x205c
> > > > > +
> > > > > +#define AR0234_PIXEL_RATE                128000000ULL
> > > > > +#define AR0234_XCLK_FREQ         19200000ULL
> > > > > +
> > > > > +#define AR0234_TEST_PATTERN_DISABLE      0
> > > > > +#define AR0234_TEST_PATTERN_SOLID_COLOR  1
> > > > > +#define AR0234_TEST_PATTERN_COLOR_BARS   2
> > > > > +#define AR0234_TEST_PATTERN_GREY_COLOR   3
> > > > > +#define AR0234_TEST_PATTERN_WALKING      256
> > > > > +
> > > > > +#define to_ar0234(_sd)   container_of(_sd, struct ar0234, sd)
> > > > > +
> > > > > +struct ar0234_reg_list {
> > > > > + u32 num_of_regs;
> > > > > + const struct cci_reg_sequence *regs; };
> > > > > +
> > > > > +struct ar0234_mode {
> > > > > + u32 width;
> > > > > + u32 height;
> > > > > + u32 hts;
> > > > > + u32 vts_def;
> > > > > + u32 code;
> > > > > + /* Sensor register settings for this mode */
> > > > > + const struct ar0234_reg_list reg_list; };
> > > > > +
> > > > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > > > + { CCI_REG16(0x3f4c), 0x121f },
> > > > > + { CCI_REG16(0x3f4e), 0x121f },
> > > > > + { CCI_REG16(0x3f50), 0x0b81 },
> > > > > + { CCI_REG16(0x31e0), 0x0003 },
> > > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > > + /* R0x3088 specify the sequencer RAM access address. */
> > > > > + { CCI_REG16(0x3088), 0x8000 },
> > > > > + /* R0x3086 write the sequencer RAM. */
> > > > > + { CCI_REG16(0x3086), 0xc1ae },
> > > > > + { CCI_REG16(0x3086), 0x327f },
> > > > > + { CCI_REG16(0x3086), 0x5780 },
> > > > > + { CCI_REG16(0x3086), 0x272f },
> > > > > + { CCI_REG16(0x3086), 0x7416 },
> > > >
> > > > Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> > > > Please move the data out to a
> > > >
> > > > static const u16 ar0234_sequencer[] = {
> > > >     0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > > >     ...
> > > > };
> > > >
> > > > table, and program it with
> > > >
> > > >     /* Program the sequencer. */
> > > >     cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > > >     for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > > >             cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > > >                       ar0234_sequencer[i], &ret);
> > > >
> > > > And please define macros for the sequencer access registers 0x3086 and
> > > > 0x3088, as well as for the bits of the 0x3088 register.
> > > >
> > > > [snip]
> > >
> > > Through communication with the vendor, we learned that this is a patch
> > > (writing to the sequencer) used to optimize the sensor's performance.
> > > It is not critical for the driver's normal operation. Therefore, I
> > > will remove this patch directly.
> >
> > I'm fine dropping it or keeping it, it's up to you. If it improves the
> > image quality I think it's useful. my only concern is that storing the
> > register address in every entry wastes space. With an optimized version
> > that only stores the data, I'm fine having the data in the driver.
> >
> > > > > + { CCI_REG16(0x302a), 0x0005 },
> > > > > + { CCI_REG16(0x302c), 0x0001 },
> > > > > + { CCI_REG16(0x302e), 0x0003 },
> > > > > + { CCI_REG16(0x3030), 0x0032 },
> > > > > + { CCI_REG16(0x3036), 0x000a },
> > > > > + { CCI_REG16(0x3038), 0x0001 },
> > > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > > + { CCI_REG16(0x31b0), 0x0082 },
> > > > > + { CCI_REG16(0x31b2), 0x005c },
> > > > > + { CCI_REG16(0x31b4), 0x5248 },
> > > > > + { CCI_REG16(0x31b6), 0x3257 },
> > > > > + { CCI_REG16(0x31b8), 0x904b },
> > > > > + { CCI_REG16(0x31ba), 0x030b },
> > > > > + { CCI_REG16(0x31bc), 0x8e09 },
> > > > > + { CCI_REG16(0x3354), 0x002b },
> > > > > + { CCI_REG16(0x31d0), 0x0000 },
> > > > > + { CCI_REG16(0x31ae), 0x0204 },
> > > > > + { CCI_REG16(0x3002), 0x0080 },
> > > > > + { CCI_REG16(0x3004), 0x0148 },
> > > > > + { CCI_REG16(0x3006), 0x043f },
> > > > > + { CCI_REG16(0x3008), 0x0647 },
> > > > > + { CCI_REG16(0x3064), 0x1802 },
> > > > > + { CCI_REG16(0x300a), 0x04c4 },
> > > > > + { CCI_REG16(0x300c), 0x04c4 },
> > > > > + { CCI_REG16(0x30a2), 0x0001 },
> > > > > + { CCI_REG16(0x30a6), 0x0001 },
> > > > > + { CCI_REG16(0x3012), 0x010c },
> > > > > + { CCI_REG16(0x3786), 0x0006 },
> > > > > + { CCI_REG16(0x31ae), 0x0202 },
> > > > > + { CCI_REG16(0x3088), 0x8050 },
> > > > > + { CCI_REG16(0x3086), 0x9237 },
> > > >
> > > > This can stay here if it needs to be programmed separately from the rest of the
> > > > sequencer data, but please use macros to replace the hardcoded register
> > > > addresses, and the value of the 0x3088 register.
> > >
> > > I will annotate each of their usages here. These are two recommended
> > > common settings provided by the vendor.
> > >
> > > > > + { CCI_REG16(0x3044), 0x0410 },
> > > > > + { CCI_REG16(0x3094), 0x03d4 },
> > > > > + { CCI_REG16(0x3096), 0x0280 },
> > > > > + { CCI_REG16(0x30ba), 0x7606 },
> > > > > + { CCI_REG16(0x30b0), 0x0028 },
> > > > > + { CCI_REG16(0x30ba), 0x7600 },
> > > > > + { CCI_REG16(0x30fe), 0x002a },
> > > > > + { CCI_REG16(0x31de), 0x0410 },
> > > > > + { CCI_REG16(0x3ed6), 0x1435 },
> > > > > + { CCI_REG16(0x3ed8), 0x9865 },
> > > > > + { CCI_REG16(0x3eda), 0x7698 },
> > > > > + { CCI_REG16(0x3edc), 0x99ff },
> > > > > + { CCI_REG16(0x3ee2), 0xbb88 },
> > > > > + { CCI_REG16(0x3ee4), 0x8836 },
> > > > > + { CCI_REG16(0x3ef0), 0x1cf0 },
> > > > > + { CCI_REG16(0x3ef2), 0x0000 },
> > > > > + { CCI_REG16(0x3ef8), 0x6166 },
> > > > > + { CCI_REG16(0x3efa), 0x3333 },
> > > > > + { CCI_REG16(0x3efc), 0x6634 },
> > > > > + { CCI_REG16(0x3088), 0x81ba },
> > > > > + { CCI_REG16(0x3086), 0x3d02 },
> > > >
> > > > Same here.
> > > >
> > > > > + { CCI_REG16(0x3276), 0x05dc },
> > > > > + { CCI_REG16(0x3f00), 0x9d05 },
> > > > > + { CCI_REG16(0x3ed2), 0xfa86 },
> > > > > + { CCI_REG16(0x3eee), 0xa4fe },
> > > > > + { CCI_REG16(0x3ecc), 0x6e42 },
> > > > > + { CCI_REG16(0x3ecc), 0x0e42 },
> > > > > + { CCI_REG16(0x3eec), 0x0c0c },
> > > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > > + { CCI_REG16(0x3ee6), 0x3363 },
> > > > > + { CCI_REG16(0x3ee6), 0x3363 },
> > > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > > + { CCI_REG16(0x3ee8), 0xaae4 },
> > > > > + { CCI_REG16(0x3180), 0xc24f },
> > > > > + { CCI_REG16(0x3102), 0x5000 },
> > > > > + { CCI_REG16(0x3060), 0x000d },
> > > > > + { CCI_REG16(0x3ed0), 0xff44 },
> > > > > + { CCI_REG16(0x3ed2), 0xaa86 },
> > > > > + { CCI_REG16(0x3ed4), 0x031f },
> > > > > + { CCI_REG16(0x3eee), 0xa4aa },
> > > >
> > > > Among all the registers above, at least the following need a macro for the
> > > > register name and register bits:
> > > >
> > > > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a, 0x302c,
> > > > 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2, 0x30a6, 0x30b0,
> > > > 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2, 0x31b4, 0x31b6, 0x31b8,
> > > > 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > > > 0x3786
> > > >
> > > > Some of them should also be handled programmatically, not hardcoded.
> > >
> > > Thanks for your comments, I replace all with macros now.
> > >
> > > > Ideally, the following registers should also be documented with macros:
> > > >
> > > > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> > >
> > > Most of the registers you listed cannot be found in the spec, and they
> > > work together within the recommended common settings provided by the
> > > vendor. Because the functions of these registers are not singular,
> > > defining macros not specified in the spec can cause misunderstandings.
> > > I add necessary comments to make code more readable.
> >
> > OK I'm fine with that.
> >
> > > > 0x30ba, in particular, varies depending on the analog gain and pixel
> > > > clock, so it needs to be handled programmatically.
> > >
> > > 0x30BA is independent of analog gain and pixel clock.
> >
> > Doesn't table 26 in the developer guide show otherwise (for bits [2:0]
> > at least) ?
> 
> I'll agree with you, but only if the pixel clock (not rate) is not 90MHz.

Indeed, it's dependent on the pixel clock. I wonder what this register
value controls.

> I haven't read through this version of the patch set to work out what
> the pixel clock is configured as. I'd queried all the clock setup and
> timing values in v2 as they looked odd.
> 
> > > Under the current pixel clock settings, 0x30BA is fixed in spec and
> > > set to 0x7606.
> 
> The bottom 3 bits being fixed at 0x6 is fine if the pixel clock is 45
> or 22.5MHz according to table 26.
> 
> > Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2
> > MHz. That's a pretty unusual value.
> 
> Not that unusual.
> If you check the mainline drivers, you'll find imx258, imx319, imx355,
> og01a1b, ov08x40, ov5670, ov5675, ov5693, and a number of others all
> use 19.2MHz clock inputs.

Thanks for pointing it out.

> There's a common element in which company submitted all those drivers....
> 
> > Given that the sensor uses a quite
> > standard PLL model, I think you can use the ccs-pll helper to calculate
> > the PLL parameters dynamically at runtime. See for instance
> > https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.pinchart@ideasonboard.com/
> > for an example of how to do so, for a sensor that has a very similar (if
> > not identical) PLL topology. Sakari can also help if you have issues
> > with the ccs-pll helper.
> >
> > > It would be better to configure it to the recommended value but not
> > > crucial (the vendor did not provide a clear explanation whether this
> > > is for image quality or performance). handling it should be considered
> > > an optimization patch if using more pxlclk configurations in the
> > > future.
> > >
> > > > > +};
> > > > > +
> > > > > +static const char * const ar0234_test_pattern_menu[] = {
> > > > > + "Disabled",
> > > > > + "Color Bars",
> > > > > + "Solid Color",
> > > > > + "Grey Color Bars",
> > > > > + "Walking 1s",
> > > > > +};
> > > > > +
> > > > > +static const int ar0234_test_pattern_val[] = {
> > > > > + AR0234_TEST_PATTERN_DISABLE,
> > > > > + AR0234_TEST_PATTERN_COLOR_BARS,
> > > > > + AR0234_TEST_PATTERN_SOLID_COLOR,
> > > > > + AR0234_TEST_PATTERN_GREY_COLOR,
> > > > > + AR0234_TEST_PATTERN_WALKING,
> > > > > +};
> > > > > +
> > > > > +static const s64 link_freq_menu_items[] = {
> > > > > + 360000000ULL,
> > > > > +};
> > > > > +
> > > > > +static const struct ar0234_mode supported_modes[] = {
> > > > > + {
> > > > > +         .width = AR0234_COMMON_WIDTH,
> > > > > +         .height = AR0234_COMMON_HEIGHT,
> > > > > +         .hts = AR0234_HTS_DEFAULT,
> > > > > +         .vts_def = AR0234_VTS_DEFAULT,
> > > > > +         .code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > +         .reg_list = {
> > > > > +                 .num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > > > +                 .regs = mode_1280x960_10bit_2lane,
> > > > > +         },
> > > > > + },
> > > > > +};
> > > > > +
> > > > > +struct ar0234 {
> > > > > + struct v4l2_subdev sd;
> > > > > + struct media_pad pad;
> > > > > + struct v4l2_ctrl_handler ctrl_handler;
> > > > > +
> > > > > + /* V4L2 Controls */
> > > > > + struct v4l2_ctrl *link_freq;
> > > > > + struct v4l2_ctrl *exposure;
> > > > > + struct v4l2_ctrl *hblank;
> > > > > + struct v4l2_ctrl *vblank;
> > > > > + struct v4l2_ctrl *vflip;
> > > > > + struct v4l2_ctrl *hflip;
> > > > > + struct regmap *regmap;
> > > > > + unsigned long link_freq_bitmap;
> > > > > + const struct ar0234_mode *cur_mode;
> > > > > +};
> > > > > +
> > > > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > > > + struct ar0234 *ar0234 =
> > > > > +         container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > + s64 exposure_max, exposure_def;
> > > > > + struct v4l2_subdev_state *state;
> > > > > + const struct v4l2_mbus_framefmt *format;
> > > > > + int ret;
> > > > > +
> > > > > + state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > > > + format = v4l2_subdev_state_get_format(state, 0);
> > > > > +
> > > > > + /* Propagate change of current control to all related controls */
> > > > > + if (ctrl->id == V4L2_CID_VBLANK) {
> > > > > +         /* Update max exposure while meeting expected vblanking */
> > > > > +         exposure_max = format->height + ctrl->val -
> > > > > +                        AR0234_EXPOSURE_MAX_MARGIN;
> > > > > +         exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> > > > > +         __v4l2_ctrl_modify_range(ar0234->exposure,
> > > > > +                                  ar0234->exposure->minimum,
> > > > > +                                  exposure_max, ar0234->exposure->step,
> > > > > +                                  exposure_def);
> > > > > + }
> > > > > +
> > > > > + /* V4L2 controls values will be applied only when power is already up */
> > > > > + if (!pm_runtime_get_if_in_use(&client->dev))
> > > > > +         return 0;
> > > > > +
> > > > > + switch (ctrl->id) {
> > > > > + case V4L2_CID_ANALOGUE_GAIN:
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > > > > +                         ctrl->val, NULL);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_CID_DIGITAL_GAIN:
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > > > > +                         ctrl->val, NULL);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_CID_EXPOSURE:
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > > > +                         ctrl->val, NULL);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_CID_VBLANK:
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > > > +                         ar0234->cur_mode->height + ctrl->val, NULL);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_CID_HFLIP:
> > > > > + case V4L2_CID_VFLIP:
> > > > > +         u64 reg;
> > > > > +
> > > > > +         ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > > +                        &reg, NULL);
> > > > > +         if (ret)
> > > > > +                 break;
> > > > > +
> > > > > +         reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > > > +                  AR0234_ORIENTATION_VFLIP);
> > > > > +         if (ar0234->hflip->val)
> > > > > +                 reg |= AR0234_ORIENTATION_HFLIP;
> > > > > +         if (ar0234->vflip->val)
> > > > > +                 reg |= AR0234_ORIENTATION_VFLIP;
> > > > > +
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > > +                         reg, NULL);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_CID_TEST_PATTERN:
> > > > > +         ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > > > > +                         ar0234_test_pattern_val[ctrl->val], NULL);
> > > > > +         break;
> > > > > +
> > > > > + default:
> > > > > +         ret = -EINVAL;
> > > > > +         break;
> > > > > + }
> > > > > +
> > > > > + pm_runtime_put(&client->dev);
> > > > > +
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > > > + .s_ctrl = ar0234_set_ctrl,
> > > > > +};
> > > > > +
> > > > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > + struct v4l2_fwnode_device_properties props;
> > > > > + struct v4l2_ctrl_handler *ctrl_hdlr;
> > > > > + s64 exposure_max, vblank_max, vblank_def, hblank;
> > > > > + u32 link_freq_size;
> > > > > + int ret;
> > > > > +
> > > > > + ctrl_hdlr = &ar0234->ctrl_handler;
> > > > > + ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > > > + if (ret)
> > > > > +         return ret;
> > > > > +
> > > > > + link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > > > + ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > > > +                                            &ar0234_ctrl_ops,
> > > > > +                                            V4L2_CID_LINK_FREQ,
> > > > > +                                            link_freq_size, 0,
> > > > > +                                            link_freq_menu_items);
> > > > > + if (ar0234->link_freq)
> > > > > +         ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > +
> > > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > V4L2_CID_ANALOGUE_GAIN,
> > > > > +                   AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> > > > > +                   AR0234_ANALOG_GAIN_STEP,
> > > > AR0234_ANALOG_GAIN_DEFAULT);
> > > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> > > > > +                   AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> > > > > +                   AR0234_GLOBAL_GAIN_STEP,
> > > > AR0234_GLOBAL_GAIN_DEFAULT);
> > > > > +
> > > > > + exposure_max = ar0234->cur_mode->vts_def -
> > > > AR0234_EXPOSURE_MAX_MARGIN;
> > > > > + ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                      V4L2_CID_EXPOSURE,
> > > > > +                                      AR0234_EXPOSURE_MIN, exposure_max,
> > > > > +                                      AR0234_EXPOSURE_STEP,
> > > > > +                                      exposure_max);
> > > > > +
> > > > > + v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> > > > > +                   AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > > > +                   AR0234_PIXEL_RATE);
> > > > > +
> > > > > + vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > > > + vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> > > > > + ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                    V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > > > +                                    vblank_def);
> > > > > + hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > > > + ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                    V4L2_CID_HBLANK, hblank, hblank, 1,
> > > > > +                                    hblank);
> > > > > + if (ar0234->hblank)
> > > > > +         ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > +
> > > > > + ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                   V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > > > + ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                   V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > > > +
> > > > > + v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                              V4L2_CID_TEST_PATTERN,
> > > > > +                              ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > > > > +                              0, 0, ar0234_test_pattern_menu);
> > > > > +
> > > > > + if (ctrl_hdlr->error)
> > > > > +         return ctrl_hdlr->error;
> > > > > +
> > > > > + ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > > > + if (ret)
> > > > > +         return ret;
> > > > > +
> > > > > + ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +                                       &props);
> > > > > + if (ret)
> > > > > +         return ret;
> > > > > +
> > > > > + ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> > > > > +                              struct v4l2_mbus_framefmt *fmt) {
> > > > > + fmt->width = mode->width;
> > > > > + fmt->height = mode->height;
> > > > > + fmt->code = mode->code;
> > > > > + fmt->field = V4L2_FIELD_NONE;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > + const struct ar0234_reg_list *reg_list;
> > > > > + int ret;
> > > > > +
> > > > > + ret = pm_runtime_resume_and_get(&client->dev);
> > > > > + if (ret < 0)
> > > > > +         return ret;
> > > > > +
> > > > > + /*
> > > > > +  * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > > > +  * the frame being generated will be truncated.
> > > > > +  */
> > > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +                 AR0234_MODE_RESET, NULL);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "failed to reset");
> > > > > +         goto err_rpm_put;
> > > > > + }
> > > > > +
> > > > > + usleep_range(1000, 1500);
> > > > > +
> > > > > + reg_list = &ar0234->cur_mode->reg_list;
> > > > > + ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > > > +                           reg_list->num_of_regs, NULL);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "failed to set mode");
> > > > > +         goto err_rpm_put;
> > > > > + }
> > > > > +
> > > > > + ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > > > + if (ret)
> > > > > +         goto err_rpm_put;
> > > > > +
> > > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +                 AR0234_MODE_STREAMING, NULL);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "failed to start stream");
> > > > > +         goto err_rpm_put;
> > > > > + }
> > > > > +
> > > > > + return 0;
> > > > > +
> > > > > +err_rpm_put:
> > > > > + pm_runtime_put(&client->dev);
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > > > + int ret;
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +
> > > > > + ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +                 AR0234_MODE_STANDBY, NULL);
> > > > > + if (ret < 0)
> > > > > +         dev_err(&client->dev, "failed to stop stream");
> > > > > +
> > > > > + pm_runtime_put(&client->dev);
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > + struct v4l2_subdev_state *state;
> > > > > + int ret = 0;
> > > > > +
> > > > > + state = v4l2_subdev_lock_and_get_active_state(sd);
> > > > > +
> > > > > + if (enable)
> > > > > +         ret = ar0234_start_streaming(ar0234);
> > > > > + else
> > > > > +         ret = ar0234_stop_streaming(ar0234);
> > > > > +
> > > > > + /* vflip and hflip cannot change during streaming */
> > > > > + __v4l2_ctrl_grab(ar0234->vflip, enable);
> > > > > + __v4l2_ctrl_grab(ar0234->hflip, enable);
> > > > > + v4l2_subdev_unlock_state(state);
> > > > > +
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > > > +                      struct v4l2_subdev_state *sd_state,
> > > > > +                      struct v4l2_subdev_format *fmt) {
> > > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > + struct v4l2_rect *crop;
> > > > > + const struct ar0234_mode *mode;
> > > > > + s64 hblank;
> > > > > + int ret;
> > > > > +
> > > > > + mode = v4l2_find_nearest_size(supported_modes,
> > > > > +                               ARRAY_SIZE(supported_modes),
> > > > > +                               width, height,
> > > > > +                               fmt->format.width,
> > > > > +                               fmt->format.height);
> > > > > +
> > > > > + crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > > > + crop->width = mode->width;
> > > > > + crop->height = mode->height;
> > > > > +
> > > > > + ar0234_update_pad_format(mode, &fmt->format);
> > > > > + *v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > > > > +
> > > > > + if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > > > +         return 0;
> > > > > +
> > > > > + ar0234->cur_mode = mode;
> > > > > +
> > > > > + hblank = AR0234_PPL_DEFAULT - mode->width;
> > > > > + ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > > > > +                                1, hblank);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "HB ctrl range update failed");
> > > > > +         return ret;
> > > > > + }
> > > > > +
> > > > > + /* Update limits and set FPS to default */
> > > > > + ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > > > +                                AR0234_VTS_MAX - mode->height, 1,
> > > > > +                                mode->vts_def - mode->height);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "VB ctrl range update failed");
> > > > > +         return ret;
> > > > > + }
> > > > > +
> > > > > + ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "VB ctrl set failed");
> > > > > +         return ret;
> > > > > + }
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > > > +                          struct v4l2_subdev_state *sd_state,
> > > > > +                          struct v4l2_subdev_mbus_code_enum *code) {
> > > > > + if (code->index > 0)
> > > > > +         return -EINVAL;
> > > > > +
> > > > > + code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > > > +                           struct v4l2_subdev_state *sd_state,
> > > > > +                           struct v4l2_subdev_frame_size_enum *fse) {
> > > > > + if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > > +         return -EINVAL;
> > > > > +
> > > > > + if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > > > +         return -EINVAL;
> > > > > +
> > > > > + fse->min_width = supported_modes[fse->index].width;
> > > > > + fse->max_width = fse->min_width;
> > > > > + fse->min_height = supported_modes[fse->index].height;
> > > > > + fse->max_height = fse->min_height;
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > > > +                         struct v4l2_subdev_state *state,
> > > > > +                         struct v4l2_subdev_selection *sel) {
> > > > > + switch (sel->target) {
> > > > > + case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > > + case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > > +         sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > > > +         sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > > > +         sel->r.width = AR0234_COMMON_WIDTH;
> > > > > +         sel->r.height = AR0234_COMMON_HEIGHT;
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_SEL_TGT_CROP:
> > > > > +         sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > > +         break;
> > > > > +
> > > > > + case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > > +         sel->r.top = 0;
> > > > > +         sel->r.left = 0;
> > > > > +         sel->r.width = AR0234_NATIVE_WIDTH;
> > > > > +         sel->r.height = AR0234_NATIVE_HEIGHT;
> > > > > +         break;
> > > > > +
> > > > > + default:
> > > > > +         return -EINVAL;
> > > > > + }
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > > > +                      struct v4l2_subdev_state *sd_state) {
> > > > > + struct v4l2_subdev_format fmt = {
> > > > > +         .which = V4L2_SUBDEV_FORMAT_TRY,
> > > > > +         .pad = 0,
> > > > > +         .format = {
> > > > > +                 .code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > +                 .width = AR0234_COMMON_WIDTH,
> > > > > +                 .height = AR0234_COMMON_HEIGHT,
> > > > > +         },
> > > > > + };
> > > > > +
> > > > > + ar0234_set_format(sd, sd_state, &fmt);
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > > > + .s_stream = ar0234_set_stream,
> > > > > +};
> > > > > +
> > > > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > > > + .set_fmt = ar0234_set_format,
> > > > > + .get_fmt = v4l2_subdev_get_fmt,
> > > > > + .enum_mbus_code = ar0234_enum_mbus_code,
> > > > > + .enum_frame_size = ar0234_enum_frame_size,
> > > > > + .get_selection = ar0234_get_selection, };
> > > > > +
> > > > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > > > + .subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > > > + .unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > > > +
> > > > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > > > + .core = &ar0234_core_ops,
> > > > > + .video = &ar0234_video_ops,
> > > > > + .pad = &ar0234_pad_ops,
> > > > > +};
> > > > > +
> > > > > +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> > > > > + .link_validate = v4l2_subdev_link_validate, };
> > > > > +
> > > > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > > > + .init_state = ar0234_init_state,
> > > > > +};
> > > > > +
> > > > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct device
> > > > > +*dev) {
> > > > > + struct fwnode_handle *endpoint;
> > > > > + struct v4l2_fwnode_endpoint bus_cfg = {
> > > > > +         .bus_type = V4L2_MBUS_CSI2_DPHY,
> > > > > + };
> > > > > + int ret;
> > > > > +
> > > > > + endpoint =
> > > > > +         fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > > > +                                         FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > > + if (!endpoint) {
> > > > > +         dev_err(dev, "endpoint node not found");
> > > > > +         return -EPROBE_DEFER;
> > > > > + }
> > > > > +
> > > > > + ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > > > + if (ret) {
> > > > > +         dev_err(dev, "parsing endpoint node failed");
> > > > > +         goto out_err;
> > > > > + }
> > > > > +
> > > > > + /* Check the number of MIPI CSI2 data lanes */
> > > > > + if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > > > +     bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > > > +         dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > > > > +         goto out_err;
> > > > > + }
> > > > > +
> > > > > + ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > > > +                                bus_cfg.nr_of_link_frequencies,
> > > > > +                                link_freq_menu_items,
> > > > > +                                ARRAY_SIZE(link_freq_menu_items),
> > > > > +                                &ar0234->link_freq_bitmap);
> > > > > + if (ret)
> > > > > +         goto out_err;
> > > > > +
> > > > > +out_err:
> > > > > + v4l2_fwnode_endpoint_free(&bus_cfg);
> > > > > + fwnode_handle_put(endpoint);
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > > > + struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > + int ret;
> > > > > + u64 val;
> > > > > +
> > > > > + ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > > > > + if (ret)
> > > > > +         return ret;
> > > > > +
> > > > > + if (val != AR0234_CHIP_ID) {
> > > > > +         dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > > > +                 AR0234_CHIP_ID, val);
> > > > > +         return -ENXIO;
> > > > > + }
> > > > > +
> > > > > + return 0;
> > > > > +}
> > > > > +
> > > > > +static void ar0234_remove(struct i2c_client *client) {
> > > > > + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > > + struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > +
> > > > > + v4l2_async_unregister_subdev(&ar0234->sd);
> > > > > + v4l2_subdev_cleanup(sd);
> > > > > + media_entity_cleanup(&ar0234->sd.entity);
> > > > > + v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > > > + pm_runtime_disable(&client->dev);
> > > > > + pm_runtime_set_suspended(&client->dev);
> > > > > +}
> > > > > +
> > > > > +static int ar0234_probe(struct i2c_client *client) {
> > > > > + struct device *dev = &client->dev;
> > > > > + struct ar0234 *ar0234;
> > > > > + struct clk *xclk;
> > > > > + u32 xclk_freq;
> > > > > + int ret;
> > > > > +
> > > > > + ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > > > > + if (!ar0234)
> > > > > +         return -ENOMEM;
> > > > > +
> > > > > + ret = ar0234_parse_fwnode(ar0234, dev);
> > > > > + if (ret)
> > > > > +         return ret;
> > > > > +
> > > > > + ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > > > + if (IS_ERR(ar0234->regmap))
> > > > > +         return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > > > +                              "failed to init CCI");
> > > > > +
> > > > > + v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > > > > +
> > > > > + xclk = devm_clk_get(dev, NULL);
> > > > > + if (IS_ERR(xclk)) {
> > > > > +         if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > > > +                 dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > > > +         return PTR_ERR(xclk);
> > > > > + }
> > > > > +
> > > > > + xclk_freq = clk_get_rate(xclk);
> > > > > + if (xclk_freq != AR0234_XCLK_FREQ) {
> > > > > +         dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > > > > +         return -EINVAL;
> > > > > + }
> > > > > +
> > > > > + /* Check module identity */
> > > > > + ret = ar0234_identify_module(ar0234);
> > > > > + if (ret) {
> > > > > +         dev_err(dev, "failed to find sensor: %d", ret);
> > > > > +         return ret;
> > > > > + }
> > > > > +
> > > > > + ar0234->cur_mode = &supported_modes[0];
> > > > > + ret = ar0234_init_controls(ar0234);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "failed to init controls: %d", ret);
> > > > > +         goto probe_error_v4l2_ctrl_handler_free;
> > > > > + }
> > > > > +
> > > > > + ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > > > + ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > > +                     V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > > + ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > > > + ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > > +
> > > > > + ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > > + ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > > > > + if (ret) {
> > > > > +         dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > > > +         goto probe_error_v4l2_ctrl_handler_free;
> > > > > + }
> > > > > +
> > > > > + ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > > > + ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > > > + if (ret < 0) {
> > > > > +         dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > > > +         goto probe_error_media_entity_cleanup;
> > > > > + }
> > > > > +
> > > > > + /*
> > > > > +  * Device is already turned on by i2c-core with ACPI domain PM.
> > > > > +  * Enable runtime PM and turn off the device.
> > > > > +  */
> > > > > + pm_runtime_set_active(&client->dev);
> > > > > + pm_runtime_enable(&client->dev);
> > > > > + pm_runtime_idle(&client->dev);
> > > > > +
> > > > > + ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > > > + if (ret < 0) {
> > > > > +         dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > > > +                 ret);
> > > > > +         goto probe_error_rpm;
> > > > > + }
> > > > > +
> > > > > + return 0;
> > > > > +probe_error_rpm:
> > > > > + pm_runtime_disable(&client->dev);
> > > > > + v4l2_subdev_cleanup(&ar0234->sd);
> > > > > +
> > > > > +probe_error_media_entity_cleanup:
> > > > > + media_entity_cleanup(&ar0234->sd.entity);
> > > > > +
> > > > > +probe_error_v4l2_ctrl_handler_free:
> > > > > + v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > > > +
> > > > > + return ret;
> > > > > +}
> > > > > +
> > > > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > > > + { "INTC10C0" },
> > > > > + {}
> > > > > +};
> > > > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > > > +
> > > > > +static struct i2c_driver ar0234_i2c_driver = {
> > > > > + .driver = {
> > > > > +         .name = "ar0234",
> > > > > +         .acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > > > + },
> > > > > + .probe = ar0234_probe,
> > > > > + .remove = ar0234_remove,
> > > > > +};
> > > > > +
> > > > > +module_i2c_driver(ar0234_i2c_driver);
> > > > > +
> > > > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > > > MODULE_LICENSE("GPL");
  

Hi Dongcheng,

On Wed, Jul 10, 2024 at 07:46:38AM +0000, Yan, Dongcheng wrote:
> On Monday, July 1, 2024 9:57 PM, Laurent Pinchart wrote:
> > On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> > > Hi Larent,
> > >
> > > Sorry for that I didn't check my sent items in time, a bug of outlook
> > > causes all commets after first quote to be lost. I have edited again
> > > and sorry for the delay.
> > 
> > No worries. I'm sorry that you have to use outlook :-)
> > 
> > > Thanks for your review and meaningful suggestions. I have contacted
> > > the vendor and optimized the code related to the register settings.
> > > The response is as follows:
> > >
> > > On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > > > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > > > The driver is implemented with V4L2 framework, and supports
> > > > > following
> > > > > features:
> > > > >
> > > > >     - manual exposure and analog/digital gain control
> > > > >     - vblank/hblank control
> > > > >     - vflip/hflip control
> > > > >     - runtime PM support
> > > > >     - 1280x960 at 30FPS
> > > > >
> > > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > > > ---
> > > > > v2 --> v3:
> > > > >     - remove unused reg setting
> > > > >     - add vflip/hflip control
> > > > >     - add external clock check & lanes check
> > > > >
> > > > > ---
> > > > >  drivers/media/i2c/Kconfig  |   11 +
> > > > >  drivers/media/i2c/Makefile |    1 +
> > > > >  drivers/media/i2c/ar0234.c | 1077
> > > > > ++++++++++++++++++++++++++++++++++++
> > > > >  3 files changed, 1089 insertions(+)  create mode 100644
> > > > > drivers/media/i2c/ar0234.c
> > > > >
> > > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> > > > > index c6d3ee472d81..7108d194c975 100644
> > > > > --- a/drivers/media/i2c/Kconfig
> > > > > +++ b/drivers/media/i2c/Kconfig
> > > > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > > > >  	  To compile this driver as a module, choose M here: the
> > > > >  	  module will be called alvium-csi2.
> > > > >
> > > > > +config VIDEO_AR0234
> > > > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > > > +        depends on ACPI || COMPILE_TEST
> > > > > +        select V4L2_CCI_I2C
> > > > > +        help
> > > > > +          This is a Video4Linux2 sensor driver for the ON Semiconductor
> > > > > +          AR0234 camera.
> > > > > +
> > > > > +          To compile this driver as a module, choose M here: the
> > > > > +          module will be called ar0234.
> > > > > +
> > > > >  config VIDEO_AR0521
> > > > >  	tristate "ON Semiconductor AR0521 sensor support"
> > > > >  	help
> > > > > diff --git a/drivers/media/i2c/Makefile
> > > > > b/drivers/media/i2c/Makefile index dfbe6448b549..57b4f62106d9
> > > > > 100644
> > > > > --- a/drivers/media/i2c/Makefile
> > > > > +++ b/drivers/media/i2c/Makefile
> > > > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > > > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > > > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > > > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > > > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > > > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > > > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o diff --git
> > > > > a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c new file
> > > > > mode 100644 index 000000000000..80fe5ffd1c64
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/i2c/ar0234.c
> > > > > @@ -0,0 +1,1077 @@
> > > > > +// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 - 2024
> > > > > +Intel Corporation.
> > > > > +
> > > > > +#include <linux/acpi.h>
> > > > > +#include <linux/clk.h>
> > > > > +#include <linux/delay.h>
> > > > > +#include <linux/i2c.h>
> > > > > +#include <linux/module.h>
> > > > > +#include <linux/pm_runtime.h>
> > > > > +#include <asm/unaligned.h>
> > > > > +
> > > > > +#include <media/v4l2-cci.h>
> > > > > +#include <media/v4l2-ctrls.h>
> > > > > +#include <media/v4l2-event.h>
> > > > > +#include <media/v4l2-device.h>
> > > > > +#include <media/v4l2-fwnode.h>
> > > > > +
> > > > > +/* Chip ID */
> > > > > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > > > > +#define AR0234_CHIP_ID			0x0a56
> > > > > +
> > > > > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > > > > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > > > > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > > > > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > > > > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > > > > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > > > > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > > > > +
> > > > > +#define AR0234_EXPOSURE_MIN		0
> > > > > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > > > > +#define AR0234_EXPOSURE_STEP		1
> > > > > +
> > > > > +#define AR0234_ANALOG_GAIN_MIN		0
> > > > > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > > > > +#define AR0234_ANALOG_GAIN_STEP		1
> > > > > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > > > > +
> > > > > +#define AR0234_GLOBAL_GAIN_MIN		0
> > > > > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > > > > +#define AR0234_GLOBAL_GAIN_STEP		1
> > > > > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > > > > +
> > > > > +#define AR0234_NATIVE_WIDTH		1920
> > > > > +#define AR0234_NATIVE_HEIGHT		1080
> > > > > +#define AR0234_COMMON_WIDTH		1280
> > > > > +#define AR0234_COMMON_HEIGHT		960
> > > > > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > > > > +#define AR0234_PIXEL_ARRAY_TOP		60
> > > > > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > > > > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > > > > +
> > > > > +#define AR0234_VTS_DEFAULT		0x04c4
> > > > > +#define AR0234_VTS_MAX			0xffff
> > > > > +#define AR0234_HTS_DEFAULT		0x04c4
> > > > > +#define AR0234_PPL_DEFAULT		3498
> > > > > +
> > > > > +#define AR0234_MODE_RESET		0x00d9
> > > > > +#define AR0234_MODE_STANDBY		0x2058
> > > > > +#define AR0234_MODE_STREAMING		0x205c
> > > > > +
> > > > > +#define AR0234_PIXEL_RATE		128000000ULL
> > > > > +#define AR0234_XCLK_FREQ		19200000ULL
> > > > > +
> > > > > +#define AR0234_TEST_PATTERN_DISABLE	0
> > > > > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > > > > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > > > > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > > > > +#define AR0234_TEST_PATTERN_WALKING	256
> > > > > +
> > > > > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > > > > +
> > > > > +struct ar0234_reg_list {
> > > > > +	u32 num_of_regs;
> > > > > +	const struct cci_reg_sequence *regs; };
> > > > > +
> > > > > +struct ar0234_mode {
> > > > > +	u32 width;
> > > > > +	u32 height;
> > > > > +	u32 hts;
> > > > > +	u32 vts_def;
> > > > > +	u32 code;
> > > > > +	/* Sensor register settings for this mode */
> > > > > +	const struct ar0234_reg_list reg_list; };
> > > > > +
> > > > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[] = {
> > > > > +	{ CCI_REG16(0x3f4c), 0x121f },
> > > > > +	{ CCI_REG16(0x3f4e), 0x121f },
> > > > > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > > > > +	{ CCI_REG16(0x31e0), 0x0003 },
> > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > +	/* R0x3088 specify the sequencer RAM access address. */
> > > > > +	{ CCI_REG16(0x3088), 0x8000 },
> > > > > +	/* R0x3086 write the sequencer RAM. */
> > > > > +	{ CCI_REG16(0x3086), 0xc1ae },
> > > > > +	{ CCI_REG16(0x3086), 0x327f },
> > > > > +	{ CCI_REG16(0x3086), 0x5780 },
> > > > > +	{ CCI_REG16(0x3086), 0x272f },
> > > > > +	{ CCI_REG16(0x3086), 0x7416 },
> > > >
> > > > Storing the sequencer data in this table wastes lots of memory and CPU cycles.
> > > > Please move the data out to a
> > > >
> > > > static const u16 ar0234_sequencer[] = {
> > > > 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > > > 	...
> > > > };
> > > >
> > > > table, and program it with
> > > >
> > > > 	/* Program the sequencer. */
> > > > 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > > > 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > > > 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > > > 			  ar0234_sequencer[i], &ret);
> > > >
> > > > And please define macros for the sequencer access registers 0x3086
> > > > and 0x3088, as well as for the bits of the 0x3088 register.
> > > >
> > > > [snip]
> > >
> > > Through communication with the vendor, we learned that this is a patch
> > > (writing to the sequencer) used to optimize the sensor's performance.
> > > It is not critical for the driver's normal operation. Therefore, I
> > > will remove this patch directly.
> > 
> > I'm fine dropping it or keeping it, it's up to you. If it improves the image quality
> > I think it's useful. my only concern is that storing the register address in every
> > entry wastes space. With an optimized version that only stores the data, I'm
> > fine having the data in the driver.
> 
> You concern is sound, moving the data to a list is a good idea to
> avoid too much stress, how about upstreaming the basic driver now and
> to upstream this optimized patch separately as vendor may fix them in
> firmware.

I'm OK with that.

> > > > > +	{ CCI_REG16(0x302a), 0x0005 },
> > > > > +	{ CCI_REG16(0x302c), 0x0001 },
> > > > > +	{ CCI_REG16(0x302e), 0x0003 },
> > > > > +	{ CCI_REG16(0x3030), 0x0032 },
> > > > > +	{ CCI_REG16(0x3036), 0x000a },
> > > > > +	{ CCI_REG16(0x3038), 0x0001 },
> > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > +	{ CCI_REG16(0x31b0), 0x0082 },
> > > > > +	{ CCI_REG16(0x31b2), 0x005c },
> > > > > +	{ CCI_REG16(0x31b4), 0x5248 },
> > > > > +	{ CCI_REG16(0x31b6), 0x3257 },
> > > > > +	{ CCI_REG16(0x31b8), 0x904b },
> > > > > +	{ CCI_REG16(0x31ba), 0x030b },
> > > > > +	{ CCI_REG16(0x31bc), 0x8e09 },
> > > > > +	{ CCI_REG16(0x3354), 0x002b },
> > > > > +	{ CCI_REG16(0x31d0), 0x0000 },
> > > > > +	{ CCI_REG16(0x31ae), 0x0204 },
> > > > > +	{ CCI_REG16(0x3002), 0x0080 },
> > > > > +	{ CCI_REG16(0x3004), 0x0148 },
> > > > > +	{ CCI_REG16(0x3006), 0x043f },
> > > > > +	{ CCI_REG16(0x3008), 0x0647 },
> > > > > +	{ CCI_REG16(0x3064), 0x1802 },
> > > > > +	{ CCI_REG16(0x300a), 0x04c4 },
> > > > > +	{ CCI_REG16(0x300c), 0x04c4 },
> > > > > +	{ CCI_REG16(0x30a2), 0x0001 },
> > > > > +	{ CCI_REG16(0x30a6), 0x0001 },
> > > > > +	{ CCI_REG16(0x3012), 0x010c },
> > > > > +	{ CCI_REG16(0x3786), 0x0006 },
> > > > > +	{ CCI_REG16(0x31ae), 0x0202 },
> > > > > +	{ CCI_REG16(0x3088), 0x8050 },
> > > > > +	{ CCI_REG16(0x3086), 0x9237 },
> > > >
> > > > This can stay here if it needs to be programmed separately from the
> > > > rest of the sequencer data, but please use macros to replace the
> > > > hardcoded register addresses, and the value of the 0x3088 register.
> > >
> > > I will annotate each of their usages here. These are two recommended
> > > common settings provided by the vendor.
> > >
> > > > > +	{ CCI_REG16(0x3044), 0x0410 },
> > > > > +	{ CCI_REG16(0x3094), 0x03d4 },
> > > > > +	{ CCI_REG16(0x3096), 0x0280 },
> > > > > +	{ CCI_REG16(0x30ba), 0x7606 },
> > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > +	{ CCI_REG16(0x30ba), 0x7600 },
> > > > > +	{ CCI_REG16(0x30fe), 0x002a },
> > > > > +	{ CCI_REG16(0x31de), 0x0410 },
> > > > > +	{ CCI_REG16(0x3ed6), 0x1435 },
> > > > > +	{ CCI_REG16(0x3ed8), 0x9865 },
> > > > > +	{ CCI_REG16(0x3eda), 0x7698 },
> > > > > +	{ CCI_REG16(0x3edc), 0x99ff },
> > > > > +	{ CCI_REG16(0x3ee2), 0xbb88 },
> > > > > +	{ CCI_REG16(0x3ee4), 0x8836 },
> > > > > +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> > > > > +	{ CCI_REG16(0x3ef2), 0x0000 },
> > > > > +	{ CCI_REG16(0x3ef8), 0x6166 },
> > > > > +	{ CCI_REG16(0x3efa), 0x3333 },
> > > > > +	{ CCI_REG16(0x3efc), 0x6634 },
> > > > > +	{ CCI_REG16(0x3088), 0x81ba },
> > > > > +	{ CCI_REG16(0x3086), 0x3d02 },
> > > >
> > > > Same here.
> > > >
> > > > > +	{ CCI_REG16(0x3276), 0x05dc },
> > > > > +	{ CCI_REG16(0x3f00), 0x9d05 },
> > > > > +	{ CCI_REG16(0x3ed2), 0xfa86 },
> > > > > +	{ CCI_REG16(0x3eee), 0xa4fe },
> > > > > +	{ CCI_REG16(0x3ecc), 0x6e42 },
> > > > > +	{ CCI_REG16(0x3ecc), 0x0e42 },
> > > > > +	{ CCI_REG16(0x3eec), 0x0c0c },
> > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > +	{ CCI_REG16(0x3180), 0xc24f },
> > > > > +	{ CCI_REG16(0x3102), 0x5000 },
> > > > > +	{ CCI_REG16(0x3060), 0x000d },
> > > > > +	{ CCI_REG16(0x3ed0), 0xff44 },
> > > > > +	{ CCI_REG16(0x3ed2), 0xaa86 },
> > > > > +	{ CCI_REG16(0x3ed4), 0x031f },
> > > > > +	{ CCI_REG16(0x3eee), 0xa4aa },
> > > >
> > > > Among all the registers above, at least the following need a macro
> > > > for the register name and register bits:
> > > >
> > > > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a,
> > > > 0x302c, 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2,
> > > > 0x30a6, 0x30b0, 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2,
> > > > 0x31b4, 0x31b6, 0x31b8, 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > > > 0x3786
> > > >
> > > > Some of them should also be handled programmatically, not hardcoded.
> > >
> > > Thanks for your comments, I replace all with macros now.
> > >
> > > > Ideally, the following registers should also be documented with macros:
> > > >
> > > > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> > >
> > > Most of the registers you listed cannot be found in the spec, and they
> > > work together within the recommended common settings provided by the
> > > vendor. Because the functions of these registers are not singular,
> > > defining macros not specified in the spec can cause misunderstandings.
> > > I add necessary comments to make code more readable.
> > 
> > OK I'm fine with that.
> > 
> > > > 0x30ba, in particular, varies depending on the analog gain and pixel
> > > > clock, so it needs to be handled programmatically.
> > >
> > > 0x30BA is independent of analog gain and pixel clock.
> > 
> > Doesn't table 26 in the developer guide show otherwise (for bits [2:0] at
> > least) ?
> 
> Maybe what I said confused you, I mean that they can achieve better
> gain quality when combined, it fixed to 6 according to vendor's
> register setting, also seen in Dave's comments. I think it can be a
> TODO if more pixel clk is used later.

OK. Could you maybe add a comment in the driver to indicate this ?

> > > Under the current pixel clock settings, 0x30BA is fixed in spec and
> > > set to 0x7606.
> > 
> > Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2 MHz.
> > That's a pretty unusual value. Given that the sensor uses a quite standard PLL
> > model, I think you can use the ccs-pll helper to calculate the PLL parameters
> > dynamically at runtime. See for instance
> > https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.pinchar
> > t@ideasonboard.com/
> > for an example of how to do so, for a sensor that has a very similar (if not
> > identical) PLL topology. Sakari can also help if you have issues with the ccs-pll
> > helper.
> 
> As Dave mentioned, 19.2MHz is the XCLK we used all along. We currently
> have no plans to use other XCLK, as using ccs-pll is not so essential
> for this sensor. Of course, I have studied the instance you provided
> carefully, and if necessary, I am willing to add this feature.

Would it be much extra work to use the CCS PLL helper ?

I understand that supporting other clock frequencies is not something
you need, and so it could be implemented later. However, using the CCS
PLL helper already means that it would be tested in your use cases,
which would help avoiding breakages in the future. If it's not much
extra work (and hopefully it won't, it's meant to be simple to use), I
think it would be very nice to use it already.

> > > It would be better to configure it to the recommended value but not
> > > crucial (the vendor did not provide a clear explanation whether this
> > > is for image quality or performance). handling it should be considered
> > > an optimization patch if using more pxlclk configurations in the
> > > future.
> > >
> > > > > +};
> > > > > +
> > > > > +static const char * const ar0234_test_pattern_menu[] = {
> > > > > +	"Disabled",
> > > > > +	"Color Bars",
> > > > > +	"Solid Color",
> > > > > +	"Grey Color Bars",
> > > > > +	"Walking 1s",
> > > > > +};
> > > > > +
> > > > > +static const int ar0234_test_pattern_val[] = {
> > > > > +	AR0234_TEST_PATTERN_DISABLE,
> > > > > +	AR0234_TEST_PATTERN_COLOR_BARS,
> > > > > +	AR0234_TEST_PATTERN_SOLID_COLOR,
> > > > > +	AR0234_TEST_PATTERN_GREY_COLOR,
> > > > > +	AR0234_TEST_PATTERN_WALKING,
> > > > > +};
> > > > > +
> > > > > +static const s64 link_freq_menu_items[] = {
> > > > > +	360000000ULL,
> > > > > +};
> > > > > +
> > > > > +static const struct ar0234_mode supported_modes[] = {
> > > > > +	{
> > > > > +		.width = AR0234_COMMON_WIDTH,
> > > > > +		.height = AR0234_COMMON_HEIGHT,
> > > > > +		.hts = AR0234_HTS_DEFAULT,
> > > > > +		.vts_def = AR0234_VTS_DEFAULT,
> > > > > +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > +		.reg_list = {
> > > > > +			.num_of_regs = ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > > > +			.regs = mode_1280x960_10bit_2lane,
> > > > > +		},
> > > > > +	},
> > > > > +};
> > > > > +
> > > > > +struct ar0234 {
> > > > > +	struct v4l2_subdev sd;
> > > > > +	struct media_pad pad;
> > > > > +	struct v4l2_ctrl_handler ctrl_handler;
> > > > > +
> > > > > +	/* V4L2 Controls */
> > > > > +	struct v4l2_ctrl *link_freq;
> > > > > +	struct v4l2_ctrl *exposure;
> > > > > +	struct v4l2_ctrl *hblank;
> > > > > +	struct v4l2_ctrl *vblank;
> > > > > +	struct v4l2_ctrl *vflip;
> > > > > +	struct v4l2_ctrl *hflip;
> > > > > +	struct regmap *regmap;
> > > > > +	unsigned long link_freq_bitmap;
> > > > > +	const struct ar0234_mode *cur_mode; };
> > > > > +
> > > > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > > > +	struct ar0234 *ar0234 =
> > > > > +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +	s64 exposure_max, exposure_def;
> > > > > +	struct v4l2_subdev_state *state;
> > > > > +	const struct v4l2_mbus_framefmt *format;
> > > > > +	int ret;
> > > > > +
> > > > > +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > > > +	format = v4l2_subdev_state_get_format(state, 0);
> > > > > +
> > > > > +	/* Propagate change of current control to all related controls */
> > > > > +	if (ctrl->id == V4L2_CID_VBLANK) {
> > > > > +		/* Update max exposure while meeting expected vblanking */
> > > > > +		exposure_max = format->height + ctrl->val -
> > > > > +			       AR0234_EXPOSURE_MAX_MARGIN;
> > > > > +		exposure_def = format->height - AR0234_EXPOSURE_MAX_MARGIN;
> > > > > +		__v4l2_ctrl_modify_range(ar0234->exposure,
> > > > > +					 ar0234->exposure->minimum,
> > > > > +					 exposure_max, ar0234->exposure->step,
> > > > > +					 exposure_def);
> > > > > +	}
> > > > > +
> > > > > +	/* V4L2 controls values will be applied only when power is already up */
> > > > > +	if (!pm_runtime_get_if_in_use(&client->dev))
> > > > > +		return 0;
> > > > > +
> > > > > +	switch (ctrl->id) {
> > > > > +	case V4L2_CID_ANALOGUE_GAIN:
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ANALOG_GAIN,
> > > > > +				ctrl->val, NULL);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_CID_DIGITAL_GAIN:
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_GLOBAL_GAIN,
> > > > > +				ctrl->val, NULL);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_CID_EXPOSURE:
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > > > +				ctrl->val, NULL);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_CID_VBLANK:
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > > > +				ar0234->cur_mode->height + ctrl->val, NULL);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_CID_HFLIP:
> > > > > +	case V4L2_CID_VFLIP:
> > > > > +		u64 reg;
> > > > > +
> > > > > +		ret = cci_read(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > > +			       &reg, NULL);
> > > > > +		if (ret)
> > > > > +			break;
> > > > > +
> > > > > +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > > > +			 AR0234_ORIENTATION_VFLIP);
> > > > > +		if (ar0234->hflip->val)
> > > > > +			reg |= AR0234_ORIENTATION_HFLIP;
> > > > > +		if (ar0234->vflip->val)
> > > > > +			reg |= AR0234_ORIENTATION_VFLIP;
> > > > > +
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_ORIENTATION,
> > > > > +				reg, NULL);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_CID_TEST_PATTERN:
> > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_TEST_PATTERN,
> > > > > +				ar0234_test_pattern_val[ctrl->val], NULL);
> > > > > +		break;
> > > > > +
> > > > > +	default:
> > > > > +		ret = -EINVAL;
> > > > > +		break;
> > > > > +	}
> > > > > +
> > > > > +	pm_runtime_put(&client->dev);
> > > > > +
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > > > +	.s_ctrl = ar0234_set_ctrl,
> > > > > +};
> > > > > +
> > > > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +	struct v4l2_fwnode_device_properties props;
> > > > > +	struct v4l2_ctrl_handler *ctrl_hdlr;
> > > > > +	s64 exposure_max, vblank_max, vblank_def, hblank;
> > > > > +	u32 link_freq_size;
> > > > > +	int ret;
> > > > > +
> > > > > +	ctrl_hdlr = &ar0234->ctrl_handler;
> > > > > +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > > > +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > > > +						   &ar0234_ctrl_ops,
> > > > > +						   V4L2_CID_LINK_FREQ,
> > > > > +						   link_freq_size, 0,
> > > > > +						   link_freq_menu_items);
> > > > > +	if (ar0234->link_freq)
> > > > > +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > +
> > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
> > > > > +			  AR0234_ANALOG_GAIN_MIN, AR0234_ANALOG_GAIN_MAX,
> > > > > +			  AR0234_ANALOG_GAIN_STEP, AR0234_ANALOG_GAIN_DEFAULT);
> > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> > > > > +			  AR0234_GLOBAL_GAIN_MIN, AR0234_GLOBAL_GAIN_MAX,
> > > > > +			  AR0234_GLOBAL_GAIN_STEP, AR0234_GLOBAL_GAIN_DEFAULT);
> > > > > +
> > > > > +	exposure_max = ar0234->cur_mode->vts_def - AR0234_EXPOSURE_MAX_MARGIN;
> > > > > +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					     V4L2_CID_EXPOSURE,
> > > > > +					     AR0234_EXPOSURE_MIN, exposure_max,
> > > > > +					     AR0234_EXPOSURE_STEP,
> > > > > +					     exposure_max);
> > > > > +
> > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops, V4L2_CID_PIXEL_RATE,
> > > > > +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > > > +			  AR0234_PIXEL_RATE);
> > > > > +
> > > > > +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > > > +	vblank_def = ar0234->cur_mode->vts_def - ar0234->cur_mode->height;
> > > > > +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > > > +					   vblank_def);
> > > > > +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > > > +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> > > > > +					   hblank);
> > > > > +	if (ar0234->hblank)
> > > > > +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > +
> > > > > +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > > > +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > > > +
> > > > > +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +				     V4L2_CID_TEST_PATTERN,
> > > > > +				     ARRAY_SIZE(ar0234_test_pattern_menu) - 1,
> > > > > +				     0, 0, ar0234_test_pattern_menu);
> > > > > +
> > > > > +	if (ctrl_hdlr->error)
> > > > > +		return ctrl_hdlr->error;
> > > > > +
> > > > > +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > +					      &props);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static void ar0234_update_pad_format(const struct ar0234_mode *mode,
> > > > > +				     struct v4l2_mbus_framefmt *fmt) {
> > > > > +	fmt->width = mode->width;
> > > > > +	fmt->height = mode->height;
> > > > > +	fmt->code = mode->code;
> > > > > +	fmt->field = V4L2_FIELD_NONE;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +	const struct ar0234_reg_list *reg_list;
> > > > > +	int ret;
> > > > > +
> > > > > +	ret = pm_runtime_resume_and_get(&client->dev);
> > > > > +	if (ret < 0)
> > > > > +		return ret;
> > > > > +
> > > > > +	/*
> > > > > +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > > > +	 * the frame being generated will be truncated.
> > > > > +	 */
> > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +			AR0234_MODE_RESET, NULL);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "failed to reset");
> > > > > +		goto err_rpm_put;
> > > > > +	}
> > > > > +
> > > > > +	usleep_range(1000, 1500);
> > > > > +
> > > > > +	reg_list = &ar0234->cur_mode->reg_list;
> > > > > +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > > > +				  reg_list->num_of_regs, NULL);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "failed to set mode");
> > > > > +		goto err_rpm_put;
> > > > > +	}
> > > > > +
> > > > > +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > > > +	if (ret)
> > > > > +		goto err_rpm_put;
> > > > > +
> > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +			AR0234_MODE_STREAMING, NULL);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "failed to start stream");
> > > > > +		goto err_rpm_put;
> > > > > +	}
> > > > > +
> > > > > +	return 0;
> > > > > +
> > > > > +err_rpm_put:
> > > > > +	pm_runtime_put(&client->dev);
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > > > +	int ret;
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +
> > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > +			AR0234_MODE_STANDBY, NULL);
> > > > > +	if (ret < 0)
> > > > > +		dev_err(&client->dev, "failed to stop stream");
> > > > > +
> > > > > +	pm_runtime_put(&client->dev);
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > +	struct v4l2_subdev_state *state;
> > > > > +	int ret = 0;
> > > > > +
> > > > > +	state = v4l2_subdev_lock_and_get_active_state(sd);
> > > > > +
> > > > > +	if (enable)
> > > > > +		ret = ar0234_start_streaming(ar0234);
> > > > > +	else
> > > > > +		ret = ar0234_stop_streaming(ar0234);
> > > > > +
> > > > > +	/* vflip and hflip cannot change during streaming */
> > > > > +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> > > > > +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> > > > > +	v4l2_subdev_unlock_state(state);
> > > > > +
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > > > +			     struct v4l2_subdev_state *sd_state,
> > > > > +			     struct v4l2_subdev_format *fmt) {
> > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +	struct v4l2_rect *crop;
> > > > > +	const struct ar0234_mode *mode;
> > > > > +	s64 hblank;
> > > > > +	int ret;
> > > > > +
> > > > > +	mode = v4l2_find_nearest_size(supported_modes,
> > > > > +				      ARRAY_SIZE(supported_modes),
> > > > > +				      width, height,
> > > > > +				      fmt->format.width,
> > > > > +				      fmt->format.height);
> > > > > +
> > > > > +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > > > +	crop->width = mode->width;
> > > > > +	crop->height = mode->height;
> > > > > +
> > > > > +	ar0234_update_pad_format(mode, &fmt->format);
> > > > > +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> > > > > +
> > > > > +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > > > +		return 0;
> > > > > +
> > > > > +	ar0234->cur_mode = mode;
> > > > > +
> > > > > +	hblank = AR0234_PPL_DEFAULT - mode->width;
> > > > > +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank, hblank,
> > > > > +				       1, hblank);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "HB ctrl range update failed");
> > > > > +		return ret;
> > > > > +	}
> > > > > +
> > > > > +	/* Update limits and set FPS to default */
> > > > > +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > > > +				       AR0234_VTS_MAX - mode->height, 1,
> > > > > +				       mode->vts_def - mode->height);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "VB ctrl range update failed");
> > > > > +		return ret;
> > > > > +	}
> > > > > +
> > > > > +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def - mode->height);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "VB ctrl set failed");
> > > > > +		return ret;
> > > > > +	}
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > > > +				 struct v4l2_subdev_state *sd_state,
> > > > > +				 struct v4l2_subdev_mbus_code_enum *code) {
> > > > > +	if (code->index > 0)
> > > > > +		return -EINVAL;
> > > > > +
> > > > > +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > > > +				  struct v4l2_subdev_state *sd_state,
> > > > > +				  struct v4l2_subdev_frame_size_enum *fse) {
> > > > > +	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > > +		return -EINVAL;
> > > > > +
> > > > > +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > > > +		return -EINVAL;
> > > > > +
> > > > > +	fse->min_width = supported_modes[fse->index].width;
> > > > > +	fse->max_width = fse->min_width;
> > > > > +	fse->min_height = supported_modes[fse->index].height;
> > > > > +	fse->max_height = fse->min_height;
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > > > +				struct v4l2_subdev_state *state,
> > > > > +				struct v4l2_subdev_selection *sel) {
> > > > > +	switch (sel->target) {
> > > > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > > +	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > > +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > > > +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > > > +		sel->r.width = AR0234_COMMON_WIDTH;
> > > > > +		sel->r.height = AR0234_COMMON_HEIGHT;
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_SEL_TGT_CROP:
> > > > > +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > > +		break;
> > > > > +
> > > > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > > +		sel->r.top = 0;
> > > > > +		sel->r.left = 0;
> > > > > +		sel->r.width = AR0234_NATIVE_WIDTH;
> > > > > +		sel->r.height = AR0234_NATIVE_HEIGHT;
> > > > > +		break;
> > > > > +
> > > > > +	default:
> > > > > +		return -EINVAL;
> > > > > +	}
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > > > +			     struct v4l2_subdev_state *sd_state) {
> > > > > +	struct v4l2_subdev_format fmt = {
> > > > > +		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > > > +		.pad = 0,
> > > > > +		.format = {
> > > > > +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > +			.width = AR0234_COMMON_WIDTH,
> > > > > +			.height = AR0234_COMMON_HEIGHT,
> > > > > +		},
> > > > > +	};
> > > > > +
> > > > > +	ar0234_set_format(sd, sd_state, &fmt);
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > > > +	.s_stream = ar0234_set_stream,
> > > > > +};
> > > > > +
> > > > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > > > +	.set_fmt = ar0234_set_format,
> > > > > +	.get_fmt = v4l2_subdev_get_fmt,
> > > > > +	.enum_mbus_code = ar0234_enum_mbus_code,
> > > > > +	.enum_frame_size = ar0234_enum_frame_size,
> > > > > +	.get_selection = ar0234_get_selection, };
> > > > > +
> > > > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > > > +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > > > +	.unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > > > +
> > > > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > > > +	.core = &ar0234_core_ops,
> > > > > +	.video = &ar0234_video_ops,
> > > > > +	.pad = &ar0234_pad_ops,
> > > > > +};
> > > > > +
> > > > > +static const struct media_entity_operations ar0234_subdev_entity_ops = {
> > > > > +	.link_validate = v4l2_subdev_link_validate, };
> > > > > +
> > > > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > > > +	.init_state = ar0234_init_state, };
> > > > > +
> > > > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct
> > > > > +device
> > > > > +*dev) {
> > > > > +	struct fwnode_handle *endpoint;
> > > > > +	struct v4l2_fwnode_endpoint bus_cfg = {
> > > > > +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> > > > > +	};
> > > > > +	int ret;
> > > > > +
> > > > > +	endpoint =
> > > > > +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > > > +						FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > > +	if (!endpoint) {
> > > > > +		dev_err(dev, "endpoint node not found");
> > > > > +		return -EPROBE_DEFER;
> > > > > +	}
> > > > > +
> > > > > +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > > > +	if (ret) {
> > > > > +		dev_err(dev, "parsing endpoint node failed");
> > > > > +		goto out_err;
> > > > > +	}
> > > > > +
> > > > > +	/* Check the number of MIPI CSI2 data lanes */
> > > > > +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > > > +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > > > +		dev_err(dev, "only 2 or 4 data lanes are currently supported");
> > > > > +		goto out_err;
> > > > > +	}
> > > > > +
> > > > > +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > > > +				       bus_cfg.nr_of_link_frequencies,
> > > > > +				       link_freq_menu_items,
> > > > > +				       ARRAY_SIZE(link_freq_menu_items),
> > > > > +				       &ar0234->link_freq_bitmap);
> > > > > +	if (ret)
> > > > > +		goto out_err;
> > > > > +
> > > > > +out_err:
> > > > > +	v4l2_fwnode_endpoint_free(&bus_cfg);
> > > > > +	fwnode_handle_put(endpoint);
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > +	int ret;
> > > > > +	u64 val;
> > > > > +
> > > > > +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val, NULL);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	if (val != AR0234_CHIP_ID) {
> > > > > +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > > > +			AR0234_CHIP_ID, val);
> > > > > +		return -ENXIO;
> > > > > +	}
> > > > > +
> > > > > +	return 0;
> > > > > +}
> > > > > +
> > > > > +static void ar0234_remove(struct i2c_client *client) {
> > > > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > +
> > > > > +	v4l2_async_unregister_subdev(&ar0234->sd);
> > > > > +	v4l2_subdev_cleanup(sd);
> > > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > > +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > > > +	pm_runtime_disable(&client->dev);
> > > > > +	pm_runtime_set_suspended(&client->dev);
> > > > > +}
> > > > > +
> > > > > +static int ar0234_probe(struct i2c_client *client) {
> > > > > +	struct device *dev = &client->dev;
> > > > > +	struct ar0234 *ar0234;
> > > > > +	struct clk *xclk;
> > > > > +	u32 xclk_freq;
> > > > > +	int ret;
> > > > > +
> > > > > +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234), GFP_KERNEL);
> > > > > +	if (!ar0234)
> > > > > +		return -ENOMEM;
> > > > > +
> > > > > +	ret = ar0234_parse_fwnode(ar0234, dev);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > > > +	if (IS_ERR(ar0234->regmap))
> > > > > +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > > > +				     "failed to init CCI");
> > > > > +
> > > > > +	v4l2_i2c_subdev_init(&ar0234->sd, client, &ar0234_subdev_ops);
> > > > > +
> > > > > +	xclk = devm_clk_get(dev, NULL);
> > > > > +	if (IS_ERR(xclk)) {
> > > > > +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > > > +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > > > +		return PTR_ERR(xclk);
> > > > > +	}
> > > > > +
> > > > > +	xclk_freq = clk_get_rate(xclk);
> > > > > +	if (xclk_freq != AR0234_XCLK_FREQ) {
> > > > > +		dev_err(dev, "xclk frequency not supported: %d Hz", xclk_freq);
> > > > > +		return -EINVAL;
> > > > > +	}
> > > > > +
> > > > > +	/* Check module identity */
> > > > > +	ret = ar0234_identify_module(ar0234);
> > > > > +	if (ret) {
> > > > > +		dev_err(dev, "failed to find sensor: %d", ret);
> > > > > +		return ret;
> > > > > +	}
> > > > > +
> > > > > +	ar0234->cur_mode = &supported_modes[0];
> > > > > +	ret = ar0234_init_controls(ar0234);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "failed to init controls: %d", ret);
> > > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > > +	}
> > > > > +
> > > > > +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > > > +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > > +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > > > +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > > +
> > > > > +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > > +	ret = media_entity_pads_init(&ar0234->sd.entity, 1, &ar0234->pad);
> > > > > +	if (ret) {
> > > > > +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > > +	}
> > > > > +
> > > > > +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > > > +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > > > +	if (ret < 0) {
> > > > > +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > > > +		goto probe_error_media_entity_cleanup;
> > > > > +	}
> > > > > +
> > > > > +	/*
> > > > > +	 * Device is already turned on by i2c-core with ACPI domain PM.
> > > > > +	 * Enable runtime PM and turn off the device.
> > > > > +	 */
> > > > > +	pm_runtime_set_active(&client->dev);
> > > > > +	pm_runtime_enable(&client->dev);
> > > > > +	pm_runtime_idle(&client->dev);
> > > > > +
> > > > > +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > > > +	if (ret < 0) {
> > > > > +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > > > +			ret);
> > > > > +		goto probe_error_rpm;
> > > > > +	}
> > > > > +
> > > > > +	return 0;
> > > > > +probe_error_rpm:
> > > > > +	pm_runtime_disable(&client->dev);
> > > > > +	v4l2_subdev_cleanup(&ar0234->sd);
> > > > > +
> > > > > +probe_error_media_entity_cleanup:
> > > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > > +
> > > > > +probe_error_v4l2_ctrl_handler_free:
> > > > > +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > > > +
> > > > > +	return ret;
> > > > > +}
> > > > > +
> > > > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > > > +	{ "INTC10C0" },
> > > > > +	{}
> > > > > +};
> > > > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > > > +
> > > > > +static struct i2c_driver ar0234_i2c_driver = {
> > > > > +	.driver = {
> > > > > +		.name = "ar0234",
> > > > > +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > > > +	},
> > > > > +	.probe = ar0234_probe,
> > > > > +	.remove = ar0234_remove,
> > > > > +};
> > > > > +
> > > > > +module_i2c_driver(ar0234_i2c_driver);
> > > > > +
> > > > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > > > > +MODULE_LICENSE("GPL");
  

Hi Laurent,

> -----Original Message-----
> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: Saturday, August 3, 2024 3:19 AM
> To: Yan, Dongcheng <dongcheng.yan@intel.com>
> Cc: sakari.ailus@linux.intel.com; linux-media@vger.kernel.org;
> tomi.valkeinen@ideasonboard.com; jacopo.mondi@ideasonboard.com;
> bingbu.cao@linux.intel.com; dave.stevenson@raspberrypi.com; Li, Daxing
> <daxing.li@intel.com>; Yao, Hao <hao.yao@intel.com>
> Subject: Re: [PATCH v3] media: i2c: Add ar0234 camera sensor driver
> 
> Hi Dongcheng,
> 
> On Wed, Jul 10, 2024 at 07:46:38AM +0000, Yan, Dongcheng wrote:
> > On Monday, July 1, 2024 9:57 PM, Laurent Pinchart wrote:
> > > On Mon, Jul 01, 2024 at 07:53:28AM +0000, Yan, Dongcheng wrote:
> > > > Hi Larent,
> > > >
> > > > Sorry for that I didn't check my sent items in time, a bug of
> > > > outlook causes all commets after first quote to be lost. I have
> > > > edited again and sorry for the delay.
> > >
> > > No worries. I'm sorry that you have to use outlook :-)
> > >
> > > > Thanks for your review and meaningful suggestions. I have
> > > > contacted the vendor and optimized the code related to the register
> settings.
> > > > The response is as follows:
> > > >
> > > > On Friday, June 14, 2024 10:25 PM, Laurent Pinchart wrote:
> > > > > On Fri, Jun 14, 2024 at 04:09:41PM +0800, Dongcheng Yan wrote:
> > > > > > The driver is implemented with V4L2 framework, and supports
> > > > > > following
> > > > > > features:
> > > > > >
> > > > > >     - manual exposure and analog/digital gain control
> > > > > >     - vblank/hblank control
> > > > > >     - vflip/hflip control
> > > > > >     - runtime PM support
> > > > > >     - 1280x960 at 30FPS
> > > > > >
> > > > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > > > Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> > > > > > ---
> > > > > > v2 --> v3:
> > > > > >     - remove unused reg setting
> > > > > >     - add vflip/hflip control
> > > > > >     - add external clock check & lanes check
> > > > > >
> > > > > > ---
> > > > > >  drivers/media/i2c/Kconfig  |   11 +
> > > > > >  drivers/media/i2c/Makefile |    1 +
> > > > > >  drivers/media/i2c/ar0234.c | 1077
> > > > > > ++++++++++++++++++++++++++++++++++++
> > > > > >  3 files changed, 1089 insertions(+)  create mode 100644
> > > > > > drivers/media/i2c/ar0234.c
> > > > > >
> > > > > > diff --git a/drivers/media/i2c/Kconfig
> > > > > > b/drivers/media/i2c/Kconfig index c6d3ee472d81..7108d194c975
> > > > > > 100644
> > > > > > --- a/drivers/media/i2c/Kconfig
> > > > > > +++ b/drivers/media/i2c/Kconfig
> > > > > > @@ -51,6 +51,17 @@ config VIDEO_ALVIUM_CSI2
> > > > > >  	  To compile this driver as a module, choose M here: the
> > > > > >  	  module will be called alvium-csi2.
> > > > > >
> > > > > > +config VIDEO_AR0234
> > > > > > +        tristate "ON Semiconductor AR0234 sensor support"
> > > > > > +        depends on ACPI || COMPILE_TEST
> > > > > > +        select V4L2_CCI_I2C
> > > > > > +        help
> > > > > > +          This is a Video4Linux2 sensor driver for the ON
> Semiconductor
> > > > > > +          AR0234 camera.
> > > > > > +
> > > > > > +          To compile this driver as a module, choose M here: the
> > > > > > +          module will be called ar0234.
> > > > > > +
> > > > > >  config VIDEO_AR0521
> > > > > >  	tristate "ON Semiconductor AR0521 sensor support"
> > > > > >  	help
> > > > > > diff --git a/drivers/media/i2c/Makefile
> > > > > > b/drivers/media/i2c/Makefile index dfbe6448b549..57b4f62106d9
> > > > > > 100644
> > > > > > --- a/drivers/media/i2c/Makefile
> > > > > > +++ b/drivers/media/i2c/Makefile
> > > > > > @@ -19,6 +19,7 @@ obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
> > > > > >  obj-$(CONFIG_VIDEO_AK881X) += ak881x.o
> > > > > >  obj-$(CONFIG_VIDEO_ALVIUM_CSI2) += alvium-csi2.o
> > > > > >  obj-$(CONFIG_VIDEO_APTINA_PLL) += aptina-pll.o
> > > > > > +obj-$(CONFIG_VIDEO_AR0234) += ar0234.o
> > > > > >  obj-$(CONFIG_VIDEO_AR0521) += ar0521.o
> > > > > >  obj-$(CONFIG_VIDEO_BT819) += bt819.o
> > > > > >  obj-$(CONFIG_VIDEO_BT856) += bt856.o diff --git
> > > > > > a/drivers/media/i2c/ar0234.c b/drivers/media/i2c/ar0234.c new
> > > > > > file mode 100644 index 000000000000..80fe5ffd1c64
> > > > > > --- /dev/null
> > > > > > +++ b/drivers/media/i2c/ar0234.c
> > > > > > @@ -0,0 +1,1077 @@
> > > > > > +// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2019 -
> > > > > > +2024 Intel Corporation.
> > > > > > +
> > > > > > +#include <linux/acpi.h>
> > > > > > +#include <linux/clk.h>
> > > > > > +#include <linux/delay.h>
> > > > > > +#include <linux/i2c.h>
> > > > > > +#include <linux/module.h>
> > > > > > +#include <linux/pm_runtime.h> #include <asm/unaligned.h>
> > > > > > +
> > > > > > +#include <media/v4l2-cci.h>
> > > > > > +#include <media/v4l2-ctrls.h> #include <media/v4l2-event.h>
> > > > > > +#include <media/v4l2-device.h> #include <media/v4l2-fwnode.h>
> > > > > > +
> > > > > > +/* Chip ID */
> > > > > > +#define AR0234_REG_CHIP_ID		CCI_REG16(0x3000)
> > > > > > +#define AR0234_CHIP_ID			0x0a56
> > > > > > +
> > > > > > +#define AR0234_REG_MODE_SELECT		CCI_REG16(0x301a)
> > > > > > +#define AR0234_REG_VTS			CCI_REG16(0x300a)
> > > > > > +#define AR0234_REG_EXPOSURE		CCI_REG16(0x3012)
> > > > > > +#define AR0234_REG_ANALOG_GAIN		CCI_REG16(0x3060)
> > > > > > +#define AR0234_REG_GLOBAL_GAIN		CCI_REG16(0x305e)
> > > > > > +#define AR0234_REG_ORIENTATION		CCI_REG16(0x3040)
> > > > > > +#define AR0234_REG_TEST_PATTERN		CCI_REG16(0x0600)
> > > > > > +
> > > > > > +#define AR0234_EXPOSURE_MIN		0
> > > > > > +#define AR0234_EXPOSURE_MAX_MARGIN	80
> > > > > > +#define AR0234_EXPOSURE_STEP		1
> > > > > > +
> > > > > > +#define AR0234_ANALOG_GAIN_MIN		0
> > > > > > +#define AR0234_ANALOG_GAIN_MAX		0x7f
> > > > > > +#define AR0234_ANALOG_GAIN_STEP		1
> > > > > > +#define AR0234_ANALOG_GAIN_DEFAULT	0xe
> > > > > > +
> > > > > > +#define AR0234_GLOBAL_GAIN_MIN		0
> > > > > > +#define AR0234_GLOBAL_GAIN_MAX		0x7ff
> > > > > > +#define AR0234_GLOBAL_GAIN_STEP		1
> > > > > > +#define AR0234_GLOBAL_GAIN_DEFAULT	0x80
> > > > > > +
> > > > > > +#define AR0234_NATIVE_WIDTH		1920
> > > > > > +#define AR0234_NATIVE_HEIGHT		1080
> > > > > > +#define AR0234_COMMON_WIDTH		1280
> > > > > > +#define AR0234_COMMON_HEIGHT		960
> > > > > > +#define AR0234_PIXEL_ARRAY_LEFT		320
> > > > > > +#define AR0234_PIXEL_ARRAY_TOP		60
> > > > > > +#define AR0234_ORIENTATION_HFLIP	BIT(14)
> > > > > > +#define AR0234_ORIENTATION_VFLIP	BIT(15)
> > > > > > +
> > > > > > +#define AR0234_VTS_DEFAULT		0x04c4
> > > > > > +#define AR0234_VTS_MAX			0xffff
> > > > > > +#define AR0234_HTS_DEFAULT		0x04c4
> > > > > > +#define AR0234_PPL_DEFAULT		3498
> > > > > > +
> > > > > > +#define AR0234_MODE_RESET		0x00d9
> > > > > > +#define AR0234_MODE_STANDBY		0x2058
> > > > > > +#define AR0234_MODE_STREAMING		0x205c
> > > > > > +
> > > > > > +#define AR0234_PIXEL_RATE		128000000ULL
> > > > > > +#define AR0234_XCLK_FREQ		19200000ULL
> > > > > > +
> > > > > > +#define AR0234_TEST_PATTERN_DISABLE	0
> > > > > > +#define AR0234_TEST_PATTERN_SOLID_COLOR	1
> > > > > > +#define AR0234_TEST_PATTERN_COLOR_BARS	2
> > > > > > +#define AR0234_TEST_PATTERN_GREY_COLOR	3
> > > > > > +#define AR0234_TEST_PATTERN_WALKING	256
> > > > > > +
> > > > > > +#define to_ar0234(_sd)	container_of(_sd, struct ar0234, sd)
> > > > > > +
> > > > > > +struct ar0234_reg_list {
> > > > > > +	u32 num_of_regs;
> > > > > > +	const struct cci_reg_sequence *regs; };
> > > > > > +
> > > > > > +struct ar0234_mode {
> > > > > > +	u32 width;
> > > > > > +	u32 height;
> > > > > > +	u32 hts;
> > > > > > +	u32 vts_def;
> > > > > > +	u32 code;
> > > > > > +	/* Sensor register settings for this mode */
> > > > > > +	const struct ar0234_reg_list reg_list; };
> > > > > > +
> > > > > > +static const struct cci_reg_sequence mode_1280x960_10bit_2lane[]
> = {
> > > > > > +	{ CCI_REG16(0x3f4c), 0x121f },
> > > > > > +	{ CCI_REG16(0x3f4e), 0x121f },
> > > > > > +	{ CCI_REG16(0x3f50), 0x0b81 },
> > > > > > +	{ CCI_REG16(0x31e0), 0x0003 },
> > > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > > +	/* R0x3088 specify the sequencer RAM access address. */
> > > > > > +	{ CCI_REG16(0x3088), 0x8000 },
> > > > > > +	/* R0x3086 write the sequencer RAM. */
> > > > > > +	{ CCI_REG16(0x3086), 0xc1ae },
> > > > > > +	{ CCI_REG16(0x3086), 0x327f },
> > > > > > +	{ CCI_REG16(0x3086), 0x5780 },
> > > > > > +	{ CCI_REG16(0x3086), 0x272f },
> > > > > > +	{ CCI_REG16(0x3086), 0x7416 },
> > > > >
> > > > > Storing the sequencer data in this table wastes lots of memory and CPU
> cycles.
> > > > > Please move the data out to a
> > > > >
> > > > > static const u16 ar0234_sequencer[] = {
> > > > > 	0xc1ae, 0x327f, 0x5780, 0x272f, 0x7416, 0x7e13, 0x8000, 0x307e,
> > > > > 	...
> > > > > };
> > > > >
> > > > > table, and program it with
> > > > >
> > > > > 	/* Program the sequencer. */
> > > > > 	cci_write(ar0234->regmap, CCI_REG16(0x3088), 0x8000, &ret);
> > > > > 	for (i = 0; i < ARRAY_SIZE(ar0234_sequencer); ++i)
> > > > > 		cci_write(ar0234->regmap, CCI_REG16(0x3086),
> > > > > 			  ar0234_sequencer[i], &ret);
> > > > >
> > > > > And please define macros for the sequencer access registers
> > > > > 0x3086 and 0x3088, as well as for the bits of the 0x3088 register.
> > > > >
> > > > > [snip]
> > > >
> > > > Through communication with the vendor, we learned that this is a
> > > > patch (writing to the sequencer) used to optimize the sensor's
> performance.
> > > > It is not critical for the driver's normal operation. Therefore, I
> > > > will remove this patch directly.
> > >
> > > I'm fine dropping it or keeping it, it's up to you. If it improves
> > > the image quality I think it's useful. my only concern is that
> > > storing the register address in every entry wastes space. With an
> > > optimized version that only stores the data, I'm fine having the data in the
> driver.
> >
> > You concern is sound, moving the data to a list is a good idea to
> > avoid too much stress, how about upstreaming the basic driver now and
> > to upstream this optimized patch separately as vendor may fix them in
> > firmware.
> 
> I'm OK with that.
> 
> > > > > > +	{ CCI_REG16(0x302a), 0x0005 },
> > > > > > +	{ CCI_REG16(0x302c), 0x0001 },
> > > > > > +	{ CCI_REG16(0x302e), 0x0003 },
> > > > > > +	{ CCI_REG16(0x3030), 0x0032 },
> > > > > > +	{ CCI_REG16(0x3036), 0x000a },
> > > > > > +	{ CCI_REG16(0x3038), 0x0001 },
> > > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > > +	{ CCI_REG16(0x31b0), 0x0082 },
> > > > > > +	{ CCI_REG16(0x31b2), 0x005c },
> > > > > > +	{ CCI_REG16(0x31b4), 0x5248 },
> > > > > > +	{ CCI_REG16(0x31b6), 0x3257 },
> > > > > > +	{ CCI_REG16(0x31b8), 0x904b },
> > > > > > +	{ CCI_REG16(0x31ba), 0x030b },
> > > > > > +	{ CCI_REG16(0x31bc), 0x8e09 },
> > > > > > +	{ CCI_REG16(0x3354), 0x002b },
> > > > > > +	{ CCI_REG16(0x31d0), 0x0000 },
> > > > > > +	{ CCI_REG16(0x31ae), 0x0204 },
> > > > > > +	{ CCI_REG16(0x3002), 0x0080 },
> > > > > > +	{ CCI_REG16(0x3004), 0x0148 },
> > > > > > +	{ CCI_REG16(0x3006), 0x043f },
> > > > > > +	{ CCI_REG16(0x3008), 0x0647 },
> > > > > > +	{ CCI_REG16(0x3064), 0x1802 },
> > > > > > +	{ CCI_REG16(0x300a), 0x04c4 },
> > > > > > +	{ CCI_REG16(0x300c), 0x04c4 },
> > > > > > +	{ CCI_REG16(0x30a2), 0x0001 },
> > > > > > +	{ CCI_REG16(0x30a6), 0x0001 },
> > > > > > +	{ CCI_REG16(0x3012), 0x010c },
> > > > > > +	{ CCI_REG16(0x3786), 0x0006 },
> > > > > > +	{ CCI_REG16(0x31ae), 0x0202 },
> > > > > > +	{ CCI_REG16(0x3088), 0x8050 },
> > > > > > +	{ CCI_REG16(0x3086), 0x9237 },
> > > > >
> > > > > This can stay here if it needs to be programmed separately from
> > > > > the rest of the sequencer data, but please use macros to replace
> > > > > the hardcoded register addresses, and the value of the 0x3088 register.
> > > >
> > > > I will annotate each of their usages here. These are two
> > > > recommended common settings provided by the vendor.
> > > >
> > > > > > +	{ CCI_REG16(0x3044), 0x0410 },
> > > > > > +	{ CCI_REG16(0x3094), 0x03d4 },
> > > > > > +	{ CCI_REG16(0x3096), 0x0280 },
> > > > > > +	{ CCI_REG16(0x30ba), 0x7606 },
> > > > > > +	{ CCI_REG16(0x30b0), 0x0028 },
> > > > > > +	{ CCI_REG16(0x30ba), 0x7600 },
> > > > > > +	{ CCI_REG16(0x30fe), 0x002a },
> > > > > > +	{ CCI_REG16(0x31de), 0x0410 },
> > > > > > +	{ CCI_REG16(0x3ed6), 0x1435 },
> > > > > > +	{ CCI_REG16(0x3ed8), 0x9865 },
> > > > > > +	{ CCI_REG16(0x3eda), 0x7698 },
> > > > > > +	{ CCI_REG16(0x3edc), 0x99ff },
> > > > > > +	{ CCI_REG16(0x3ee2), 0xbb88 },
> > > > > > +	{ CCI_REG16(0x3ee4), 0x8836 },
> > > > > > +	{ CCI_REG16(0x3ef0), 0x1cf0 },
> > > > > > +	{ CCI_REG16(0x3ef2), 0x0000 },
> > > > > > +	{ CCI_REG16(0x3ef8), 0x6166 },
> > > > > > +	{ CCI_REG16(0x3efa), 0x3333 },
> > > > > > +	{ CCI_REG16(0x3efc), 0x6634 },
> > > > > > +	{ CCI_REG16(0x3088), 0x81ba },
> > > > > > +	{ CCI_REG16(0x3086), 0x3d02 },
> > > > >
> > > > > Same here.
> > > > >
> > > > > > +	{ CCI_REG16(0x3276), 0x05dc },
> > > > > > +	{ CCI_REG16(0x3f00), 0x9d05 },
> > > > > > +	{ CCI_REG16(0x3ed2), 0xfa86 },
> > > > > > +	{ CCI_REG16(0x3eee), 0xa4fe },
> > > > > > +	{ CCI_REG16(0x3ecc), 0x6e42 },
> > > > > > +	{ CCI_REG16(0x3ecc), 0x0e42 },
> > > > > > +	{ CCI_REG16(0x3eec), 0x0c0c },
> > > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > > > +	{ CCI_REG16(0x3ee6), 0x3363 },
> > > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > > +	{ CCI_REG16(0x3ee8), 0xaae4 },
> > > > > > +	{ CCI_REG16(0x3180), 0xc24f },
> > > > > > +	{ CCI_REG16(0x3102), 0x5000 },
> > > > > > +	{ CCI_REG16(0x3060), 0x000d },
> > > > > > +	{ CCI_REG16(0x3ed0), 0xff44 },
> > > > > > +	{ CCI_REG16(0x3ed2), 0xaa86 },
> > > > > > +	{ CCI_REG16(0x3ed4), 0x031f },
> > > > > > +	{ CCI_REG16(0x3eee), 0xa4aa },
> > > > >
> > > > > Among all the registers above, at least the following need a
> > > > > macro for the register name and register bits:
> > > > >
> > > > > 0x3002, 0x3004, 0x3006, 0x3008, 0x300a, 0x300c, 0x3012, 0x302a,
> > > > > 0x302c, 0x302e, 0x3030, 0x3036, 0x3038, 0x3060, 0x3064, 0x30a2,
> > > > > 0x30a6, 0x30b0, 0x30fe, 0x3102, 0x3180, 0x31ae, 0x31b0, 0x31b2,
> > > > > 0x31b4, 0x31b6, 0x31b8, 0x31ba, 0x31bc, 0x31d0, 0x31e0, 0x3354,
> > > > > 0x3786
> > > > >
> > > > > Some of them should also be handled programmatically, not
> hardcoded.
> > > >
> > > > Thanks for your comments, I replace all with macros now.
> > > >
> > > > > Ideally, the following registers should also be documented with macros:
> > > > >
> > > > > 0x3044, 0x3094, 0x3096, 0x30ba, 0x31de, 0x3276
> > > >
> > > > Most of the registers you listed cannot be found in the spec, and
> > > > they work together within the recommended common settings provided
> > > > by the vendor. Because the functions of these registers are not
> > > > singular, defining macros not specified in the spec can cause
> misunderstandings.
> > > > I add necessary comments to make code more readable.
> > >
> > > OK I'm fine with that.
> > >

Thank you for your understanding.

> > > > > 0x30ba, in particular, varies depending on the analog gain and
> > > > > pixel clock, so it needs to be handled programmatically.
> > > >
> > > > 0x30BA is independent of analog gain and pixel clock.
> > >
> > > Doesn't table 26 in the developer guide show otherwise (for bits
> > > [2:0] at
> > > least) ?
> >
> > Maybe what I said confused you, I mean that they can achieve better
> > gain quality when combined, it fixed to 6 according to vendor's
> > register setting, also seen in Dave's comments. I think it can be a
> > TODO if more pixel clk is used later.
> 
> OK. Could you maybe add a comment in the driver to indicate this ?
> 

Sure, I will add.

> > > > Under the current pixel clock settings, 0x30BA is fixed in spec
> > > > and set to 0x7606.
> > >
> > > Right. I've looked at the clock speed, AR0234_XCLK_FREQ is set to 19.2
> MHz.
> > > That's a pretty unusual value. Given that the sensor uses a quite
> > > standard PLL model, I think you can use the ccs-pll helper to
> > > calculate the PLL parameters dynamically at runtime. See for
> > > instance
> > > https://lore.kernel.org/linux-media/20240630141802.15830-3-laurent.p
> > > inchar
> > > t@ideasonboard.com/
> > > for an example of how to do so, for a sensor that has a very similar
> > > (if not
> > > identical) PLL topology. Sakari can also help if you have issues
> > > with the ccs-pll helper.
> >
> > As Dave mentioned, 19.2MHz is the XCLK we used all along. We currently
> > have no plans to use other XCLK, as using ccs-pll is not so essential
> > for this sensor. Of course, I have studied the instance you provided
> > carefully, and if necessary, I am willing to add this feature.
> 
> Would it be much extra work to use the CCS PLL helper ?
> 
> I understand that supporting other clock frequencies is not something you
> need, and so it could be implemented later. However, using the CCS PLL helper
> already means that it would be tested in your use cases, which would help
> avoiding breakages in the future. If it's not much extra work (and hopefully it
> won't, it's meant to be simple to use), I think it would be very nice to use it
> already.
> 

Thanks for your persuasive advice, I will add this CCS PLL helper.

Best Regards,
Dongcheng

> > > > It would be better to configure it to the recommended value but
> > > > not crucial (the vendor did not provide a clear explanation
> > > > whether this is for image quality or performance). handling it
> > > > should be considered an optimization patch if using more pxlclk
> > > > configurations in the future.
> > > >
> > > > > > +};
> > > > > > +
> > > > > > +static const char * const ar0234_test_pattern_menu[] = {
> > > > > > +	"Disabled",
> > > > > > +	"Color Bars",
> > > > > > +	"Solid Color",
> > > > > > +	"Grey Color Bars",
> > > > > > +	"Walking 1s",
> > > > > > +};
> > > > > > +
> > > > > > +static const int ar0234_test_pattern_val[] = {
> > > > > > +	AR0234_TEST_PATTERN_DISABLE,
> > > > > > +	AR0234_TEST_PATTERN_COLOR_BARS,
> > > > > > +	AR0234_TEST_PATTERN_SOLID_COLOR,
> > > > > > +	AR0234_TEST_PATTERN_GREY_COLOR,
> > > > > > +	AR0234_TEST_PATTERN_WALKING, };
> > > > > > +
> > > > > > +static const s64 link_freq_menu_items[] = {
> > > > > > +	360000000ULL,
> > > > > > +};
> > > > > > +
> > > > > > +static const struct ar0234_mode supported_modes[] = {
> > > > > > +	{
> > > > > > +		.width = AR0234_COMMON_WIDTH,
> > > > > > +		.height = AR0234_COMMON_HEIGHT,
> > > > > > +		.hts = AR0234_HTS_DEFAULT,
> > > > > > +		.vts_def = AR0234_VTS_DEFAULT,
> > > > > > +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > > +		.reg_list = {
> > > > > > +			.num_of_regs =
> ARRAY_SIZE(mode_1280x960_10bit_2lane),
> > > > > > +			.regs = mode_1280x960_10bit_2lane,
> > > > > > +		},
> > > > > > +	},
> > > > > > +};
> > > > > > +
> > > > > > +struct ar0234 {
> > > > > > +	struct v4l2_subdev sd;
> > > > > > +	struct media_pad pad;
> > > > > > +	struct v4l2_ctrl_handler ctrl_handler;
> > > > > > +
> > > > > > +	/* V4L2 Controls */
> > > > > > +	struct v4l2_ctrl *link_freq;
> > > > > > +	struct v4l2_ctrl *exposure;
> > > > > > +	struct v4l2_ctrl *hblank;
> > > > > > +	struct v4l2_ctrl *vblank;
> > > > > > +	struct v4l2_ctrl *vflip;
> > > > > > +	struct v4l2_ctrl *hflip;
> > > > > > +	struct regmap *regmap;
> > > > > > +	unsigned long link_freq_bitmap;
> > > > > > +	const struct ar0234_mode *cur_mode; };
> > > > > > +
> > > > > > +static int ar0234_set_ctrl(struct v4l2_ctrl *ctrl) {
> > > > > > +	struct ar0234 *ar0234 =
> > > > > > +		container_of(ctrl->handler, struct ar0234, ctrl_handler);
> > > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +	s64 exposure_max, exposure_def;
> > > > > > +	struct v4l2_subdev_state *state;
> > > > > > +	const struct v4l2_mbus_framefmt *format;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	state = v4l2_subdev_get_locked_active_state(&ar0234->sd);
> > > > > > +	format = v4l2_subdev_state_get_format(state, 0);
> > > > > > +
> > > > > > +	/* Propagate change of current control to all related controls */
> > > > > > +	if (ctrl->id == V4L2_CID_VBLANK) {
> > > > > > +		/* Update max exposure while meeting expected vblanking
> */
> > > > > > +		exposure_max = format->height + ctrl->val -
> > > > > > +			       AR0234_EXPOSURE_MAX_MARGIN;
> > > > > > +		exposure_def = format->height -
> AR0234_EXPOSURE_MAX_MARGIN;
> > > > > > +		__v4l2_ctrl_modify_range(ar0234->exposure,
> > > > > > +					 ar0234->exposure->minimum,
> > > > > > +					 exposure_max, ar0234->exposure->step,
> > > > > > +					 exposure_def);
> > > > > > +	}
> > > > > > +
> > > > > > +	/* V4L2 controls values will be applied only when power is
> already up */
> > > > > > +	if (!pm_runtime_get_if_in_use(&client->dev))
> > > > > > +		return 0;
> > > > > > +
> > > > > > +	switch (ctrl->id) {
> > > > > > +	case V4L2_CID_ANALOGUE_GAIN:
> > > > > > +		ret = cci_write(ar0234->regmap,
> AR0234_REG_ANALOG_GAIN,
> > > > > > +				ctrl->val, NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_CID_DIGITAL_GAIN:
> > > > > > +		ret = cci_write(ar0234->regmap,
> AR0234_REG_GLOBAL_GAIN,
> > > > > > +				ctrl->val, NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_CID_EXPOSURE:
> > > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_EXPOSURE,
> > > > > > +				ctrl->val, NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_CID_VBLANK:
> > > > > > +		ret = cci_write(ar0234->regmap, AR0234_REG_VTS,
> > > > > > +				ar0234->cur_mode->height + ctrl->val, NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_CID_HFLIP:
> > > > > > +	case V4L2_CID_VFLIP:
> > > > > > +		u64 reg;
> > > > > > +
> > > > > > +		ret = cci_read(ar0234->regmap,
> AR0234_REG_ORIENTATION,
> > > > > > +			       &reg, NULL);
> > > > > > +		if (ret)
> > > > > > +			break;
> > > > > > +
> > > > > > +		reg &= ~(AR0234_ORIENTATION_HFLIP |
> > > > > > +			 AR0234_ORIENTATION_VFLIP);
> > > > > > +		if (ar0234->hflip->val)
> > > > > > +			reg |= AR0234_ORIENTATION_HFLIP;
> > > > > > +		if (ar0234->vflip->val)
> > > > > > +			reg |= AR0234_ORIENTATION_VFLIP;
> > > > > > +
> > > > > > +		ret = cci_write(ar0234->regmap,
> AR0234_REG_ORIENTATION,
> > > > > > +				reg, NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_CID_TEST_PATTERN:
> > > > > > +		ret = cci_write(ar0234->regmap,
> AR0234_REG_TEST_PATTERN,
> > > > > > +				ar0234_test_pattern_val[ctrl->val], NULL);
> > > > > > +		break;
> > > > > > +
> > > > > > +	default:
> > > > > > +		ret = -EINVAL;
> > > > > > +		break;
> > > > > > +	}
> > > > > > +
> > > > > > +	pm_runtime_put(&client->dev);
> > > > > > +
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static const struct v4l2_ctrl_ops ar0234_ctrl_ops = {
> > > > > > +	.s_ctrl = ar0234_set_ctrl,
> > > > > > +};
> > > > > > +
> > > > > > +static int ar0234_init_controls(struct ar0234 *ar0234) {
> > > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +	struct v4l2_fwnode_device_properties props;
> > > > > > +	struct v4l2_ctrl_handler *ctrl_hdlr;
> > > > > > +	s64 exposure_max, vblank_max, vblank_def, hblank;
> > > > > > +	u32 link_freq_size;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	ctrl_hdlr = &ar0234->ctrl_handler;
> > > > > > +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
> > > > > > +	if (ret)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	link_freq_size = ARRAY_SIZE(link_freq_menu_items) - 1;
> > > > > > +	ar0234->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > > > > +						   &ar0234_ctrl_ops,
> > > > > > +						   V4L2_CID_LINK_FREQ,
> > > > > > +						   link_freq_size, 0,
> > > > > > +						   link_freq_menu_items);
> > > > > > +	if (ar0234->link_freq)
> > > > > > +		ar0234->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > > +
> > > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_ANALOGUE_GAIN,
> > > > > > +			  AR0234_ANALOG_GAIN_MIN,
> AR0234_ANALOG_GAIN_MAX,
> > > > > > +			  AR0234_ANALOG_GAIN_STEP,
> AR0234_ANALOG_GAIN_DEFAULT);
> > > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_DIGITAL_GAIN,
> > > > > > +			  AR0234_GLOBAL_GAIN_MIN,
> AR0234_GLOBAL_GAIN_MAX,
> > > > > > +			  AR0234_GLOBAL_GAIN_STEP,
> AR0234_GLOBAL_GAIN_DEFAULT);
> > > > > > +
> > > > > > +	exposure_max = ar0234->cur_mode->vts_def -
> AR0234_EXPOSURE_MAX_MARGIN;
> > > > > > +	ar0234->exposure = v4l2_ctrl_new_std(ctrl_hdlr,
> &ar0234_ctrl_ops,
> > > > > > +					     V4L2_CID_EXPOSURE,
> > > > > > +					     AR0234_EXPOSURE_MIN,
> exposure_max,
> > > > > > +					     AR0234_EXPOSURE_STEP,
> > > > > > +					     exposure_max);
> > > > > > +
> > > > > > +	v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> V4L2_CID_PIXEL_RATE,
> > > > > > +			  AR0234_PIXEL_RATE, AR0234_PIXEL_RATE, 1,
> > > > > > +			  AR0234_PIXEL_RATE);
> > > > > > +
> > > > > > +	vblank_max = AR0234_VTS_MAX - ar0234->cur_mode->height;
> > > > > > +	vblank_def = ar0234->cur_mode->vts_def -
> ar0234->cur_mode->height;
> > > > > > +	ar0234->vblank = v4l2_ctrl_new_std(ctrl_hdlr,
> &ar0234_ctrl_ops,
> > > > > > +					   V4L2_CID_VBLANK, 0, vblank_max, 1,
> > > > > > +					   vblank_def);
> > > > > > +	hblank = AR0234_PPL_DEFAULT - ar0234->cur_mode->width;
> > > > > > +	ar0234->hblank = v4l2_ctrl_new_std(ctrl_hdlr,
> &ar0234_ctrl_ops,
> > > > > > +					   V4L2_CID_HBLANK, hblank, hblank, 1,
> > > > > > +					   hblank);
> > > > > > +	if (ar0234->hblank)
> > > > > > +		ar0234->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > > > > +
> > > > > > +	ar0234->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > > +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> > > > > > +	ar0234->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > > +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> > > > > > +
> > > > > > +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &ar0234_ctrl_ops,
> > > > > > +				     V4L2_CID_TEST_PATTERN,
> > > > > > +				     ARRAY_SIZE(ar0234_test_pattern_menu) -
> 1,
> > > > > > +				     0, 0, ar0234_test_pattern_menu);
> > > > > > +
> > > > > > +	if (ctrl_hdlr->error)
> > > > > > +		return ctrl_hdlr->error;
> > > > > > +
> > > > > > +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> > > > > > +	if (ret)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr,
> &ar0234_ctrl_ops,
> > > > > > +					      &props);
> > > > > > +	if (ret)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	ar0234->sd.ctrl_handler = ctrl_hdlr;
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static void ar0234_update_pad_format(const struct ar0234_mode
> *mode,
> > > > > > +				     struct v4l2_mbus_framefmt *fmt) {
> > > > > > +	fmt->width = mode->width;
> > > > > > +	fmt->height = mode->height;
> > > > > > +	fmt->code = mode->code;
> > > > > > +	fmt->field = V4L2_FIELD_NONE; }
> > > > > > +
> > > > > > +static int ar0234_start_streaming(struct ar0234 *ar0234) {
> > > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +	const struct ar0234_reg_list *reg_list;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	ret = pm_runtime_resume_and_get(&client->dev);
> > > > > > +	if (ret < 0)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	/*
> > > > > > +	 * Setting 0x301A.bit[0] will initiate a reset sequence:
> > > > > > +	 * the frame being generated will be truncated.
> > > > > > +	 */
> > > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > > +			AR0234_MODE_RESET, NULL);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "failed to reset");
> > > > > > +		goto err_rpm_put;
> > > > > > +	}
> > > > > > +
> > > > > > +	usleep_range(1000, 1500);
> > > > > > +
> > > > > > +	reg_list = &ar0234->cur_mode->reg_list;
> > > > > > +	ret = cci_multi_reg_write(ar0234->regmap, reg_list->regs,
> > > > > > +				  reg_list->num_of_regs, NULL);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "failed to set mode");
> > > > > > +		goto err_rpm_put;
> > > > > > +	}
> > > > > > +
> > > > > > +	ret = __v4l2_ctrl_handler_setup(ar0234->sd.ctrl_handler);
> > > > > > +	if (ret)
> > > > > > +		goto err_rpm_put;
> > > > > > +
> > > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > > +			AR0234_MODE_STREAMING, NULL);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "failed to start stream");
> > > > > > +		goto err_rpm_put;
> > > > > > +	}
> > > > > > +
> > > > > > +	return 0;
> > > > > > +
> > > > > > +err_rpm_put:
> > > > > > +	pm_runtime_put(&client->dev);
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_stop_streaming(struct ar0234 *ar0234) {
> > > > > > +	int ret;
> > > > > > +	struct i2c_client *client =
> > > > > > +v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +
> > > > > > +	ret = cci_write(ar0234->regmap, AR0234_REG_MODE_SELECT,
> > > > > > +			AR0234_MODE_STANDBY, NULL);
> > > > > > +	if (ret < 0)
> > > > > > +		dev_err(&client->dev, "failed to stop stream");
> > > > > > +
> > > > > > +	pm_runtime_put(&client->dev);
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_set_stream(struct v4l2_subdev *sd, int enable) {
> > > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > > +	struct v4l2_subdev_state *state;
> > > > > > +	int ret = 0;
> > > > > > +
> > > > > > +	state = v4l2_subdev_lock_and_get_active_state(sd);
> > > > > > +
> > > > > > +	if (enable)
> > > > > > +		ret = ar0234_start_streaming(ar0234);
> > > > > > +	else
> > > > > > +		ret = ar0234_stop_streaming(ar0234);
> > > > > > +
> > > > > > +	/* vflip and hflip cannot change during streaming */
> > > > > > +	__v4l2_ctrl_grab(ar0234->vflip, enable);
> > > > > > +	__v4l2_ctrl_grab(ar0234->hflip, enable);
> > > > > > +	v4l2_subdev_unlock_state(state);
> > > > > > +
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_set_format(struct v4l2_subdev *sd,
> > > > > > +			     struct v4l2_subdev_state *sd_state,
> > > > > > +			     struct v4l2_subdev_format *fmt) {
> > > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +	struct v4l2_rect *crop;
> > > > > > +	const struct ar0234_mode *mode;
> > > > > > +	s64 hblank;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	mode = v4l2_find_nearest_size(supported_modes,
> > > > > > +				      ARRAY_SIZE(supported_modes),
> > > > > > +				      width, height,
> > > > > > +				      fmt->format.width,
> > > > > > +				      fmt->format.height);
> > > > > > +
> > > > > > +	crop = v4l2_subdev_state_get_crop(sd_state, fmt->pad);
> > > > > > +	crop->width = mode->width;
> > > > > > +	crop->height = mode->height;
> > > > > > +
> > > > > > +	ar0234_update_pad_format(mode, &fmt->format);
> > > > > > +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) =
> > > > > > +fmt->format;
> > > > > > +
> > > > > > +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > > > > > +		return 0;
> > > > > > +
> > > > > > +	ar0234->cur_mode = mode;
> > > > > > +
> > > > > > +	hblank = AR0234_PPL_DEFAULT - mode->width;
> > > > > > +	ret = __v4l2_ctrl_modify_range(ar0234->hblank, hblank,
> hblank,
> > > > > > +				       1, hblank);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "HB ctrl range update failed");
> > > > > > +		return ret;
> > > > > > +	}
> > > > > > +
> > > > > > +	/* Update limits and set FPS to default */
> > > > > > +	ret = __v4l2_ctrl_modify_range(ar0234->vblank, 0,
> > > > > > +				       AR0234_VTS_MAX - mode->height, 1,
> > > > > > +				       mode->vts_def - mode->height);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "VB ctrl range update failed");
> > > > > > +		return ret;
> > > > > > +	}
> > > > > > +
> > > > > > +	ret = __v4l2_ctrl_s_ctrl(ar0234->vblank, mode->vts_def -
> mode->height);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "VB ctrl set failed");
> > > > > > +		return ret;
> > > > > > +	}
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_enum_mbus_code(struct v4l2_subdev *sd,
> > > > > > +				 struct v4l2_subdev_state *sd_state,
> > > > > > +				 struct v4l2_subdev_mbus_code_enum *code) {
> > > > > > +	if (code->index > 0)
> > > > > > +		return -EINVAL;
> > > > > > +
> > > > > > +	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_enum_frame_size(struct v4l2_subdev *sd,
> > > > > > +				  struct v4l2_subdev_state *sd_state,
> > > > > > +				  struct v4l2_subdev_frame_size_enum *fse) {
> > > > > > +	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > > > +		return -EINVAL;
> > > > > > +
> > > > > > +	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
> > > > > > +		return -EINVAL;
> > > > > > +
> > > > > > +	fse->min_width = supported_modes[fse->index].width;
> > > > > > +	fse->max_width = fse->min_width;
> > > > > > +	fse->min_height = supported_modes[fse->index].height;
> > > > > > +	fse->max_height = fse->min_height;
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_get_selection(struct v4l2_subdev *sd,
> > > > > > +				struct v4l2_subdev_state *state,
> > > > > > +				struct v4l2_subdev_selection *sel) {
> > > > > > +	switch (sel->target) {
> > > > > > +	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > > > > +	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > > > +		sel->r.top = AR0234_PIXEL_ARRAY_TOP;
> > > > > > +		sel->r.left = AR0234_PIXEL_ARRAY_LEFT;
> > > > > > +		sel->r.width = AR0234_COMMON_WIDTH;
> > > > > > +		sel->r.height = AR0234_COMMON_HEIGHT;
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_SEL_TGT_CROP:
> > > > > > +		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > > > +		break;
> > > > > > +
> > > > > > +	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > > > +		sel->r.top = 0;
> > > > > > +		sel->r.left = 0;
> > > > > > +		sel->r.width = AR0234_NATIVE_WIDTH;
> > > > > > +		sel->r.height = AR0234_NATIVE_HEIGHT;
> > > > > > +		break;
> > > > > > +
> > > > > > +	default:
> > > > > > +		return -EINVAL;
> > > > > > +	}
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_init_state(struct v4l2_subdev *sd,
> > > > > > +			     struct v4l2_subdev_state *sd_state) {
> > > > > > +	struct v4l2_subdev_format fmt = {
> > > > > > +		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > > > > +		.pad = 0,
> > > > > > +		.format = {
> > > > > > +			.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > > > > +			.width = AR0234_COMMON_WIDTH,
> > > > > > +			.height = AR0234_COMMON_HEIGHT,
> > > > > > +		},
> > > > > > +	};
> > > > > > +
> > > > > > +	ar0234_set_format(sd, sd_state, &fmt);
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static const struct v4l2_subdev_video_ops ar0234_video_ops = {
> > > > > > +	.s_stream = ar0234_set_stream, };
> > > > > > +
> > > > > > +static const struct v4l2_subdev_pad_ops ar0234_pad_ops = {
> > > > > > +	.set_fmt = ar0234_set_format,
> > > > > > +	.get_fmt = v4l2_subdev_get_fmt,
> > > > > > +	.enum_mbus_code = ar0234_enum_mbus_code,
> > > > > > +	.enum_frame_size = ar0234_enum_frame_size,
> > > > > > +	.get_selection = ar0234_get_selection, };
> > > > > > +
> > > > > > +static const struct v4l2_subdev_core_ops ar0234_core_ops = {
> > > > > > +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> > > > > > +	.unsubscribe_event = v4l2_event_subdev_unsubscribe, };
> > > > > > +
> > > > > > +static const struct v4l2_subdev_ops ar0234_subdev_ops = {
> > > > > > +	.core = &ar0234_core_ops,
> > > > > > +	.video = &ar0234_video_ops,
> > > > > > +	.pad = &ar0234_pad_ops,
> > > > > > +};
> > > > > > +
> > > > > > +static const struct media_entity_operations
> ar0234_subdev_entity_ops = {
> > > > > > +	.link_validate = v4l2_subdev_link_validate, };
> > > > > > +
> > > > > > +static const struct v4l2_subdev_internal_ops ar0234_internal_ops = {
> > > > > > +	.init_state = ar0234_init_state, };
> > > > > > +
> > > > > > +static int ar0234_parse_fwnode(struct ar0234 *ar0234, struct
> > > > > > +device
> > > > > > +*dev) {
> > > > > > +	struct fwnode_handle *endpoint;
> > > > > > +	struct v4l2_fwnode_endpoint bus_cfg = {
> > > > > > +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> > > > > > +	};
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	endpoint =
> > > > > > +		fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> > > > > > +						FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > > > +	if (!endpoint) {
> > > > > > +		dev_err(dev, "endpoint node not found");
> > > > > > +		return -EPROBE_DEFER;
> > > > > > +	}
> > > > > > +
> > > > > > +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(dev, "parsing endpoint node failed");
> > > > > > +		goto out_err;
> > > > > > +	}
> > > > > > +
> > > > > > +	/* Check the number of MIPI CSI2 data lanes */
> > > > > > +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2 &&
> > > > > > +	    bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> > > > > > +		dev_err(dev, "only 2 or 4 data lanes are currently
> supported");
> > > > > > +		goto out_err;
> > > > > > +	}
> > > > > > +
> > > > > > +	ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
> > > > > > +				       bus_cfg.nr_of_link_frequencies,
> > > > > > +				       link_freq_menu_items,
> > > > > > +				       ARRAY_SIZE(link_freq_menu_items),
> > > > > > +				       &ar0234->link_freq_bitmap);
> > > > > > +	if (ret)
> > > > > > +		goto out_err;
> > > > > > +
> > > > > > +out_err:
> > > > > > +	v4l2_fwnode_endpoint_free(&bus_cfg);
> > > > > > +	fwnode_handle_put(endpoint);
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_identify_module(struct ar0234 *ar0234) {
> > > > > > +	struct i2c_client *client = v4l2_get_subdevdata(&ar0234->sd);
> > > > > > +	int ret;
> > > > > > +	u64 val;
> > > > > > +
> > > > > > +	ret = cci_read(ar0234->regmap, AR0234_REG_CHIP_ID, &val,
> NULL);
> > > > > > +	if (ret)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	if (val != AR0234_CHIP_ID) {
> > > > > > +		dev_err(&client->dev, "chip id mismatch: %x!=%llx",
> > > > > > +			AR0234_CHIP_ID, val);
> > > > > > +		return -ENXIO;
> > > > > > +	}
> > > > > > +
> > > > > > +	return 0;
> > > > > > +}
> > > > > > +
> > > > > > +static void ar0234_remove(struct i2c_client *client) {
> > > > > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > > > +	struct ar0234 *ar0234 = to_ar0234(sd);
> > > > > > +
> > > > > > +	v4l2_async_unregister_subdev(&ar0234->sd);
> > > > > > +	v4l2_subdev_cleanup(sd);
> > > > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > > > +	v4l2_ctrl_handler_free(&ar0234->ctrl_handler);
> > > > > > +	pm_runtime_disable(&client->dev);
> > > > > > +	pm_runtime_set_suspended(&client->dev);
> > > > > > +}
> > > > > > +
> > > > > > +static int ar0234_probe(struct i2c_client *client) {
> > > > > > +	struct device *dev = &client->dev;
> > > > > > +	struct ar0234 *ar0234;
> > > > > > +	struct clk *xclk;
> > > > > > +	u32 xclk_freq;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	ar0234 = devm_kzalloc(&client->dev, sizeof(*ar0234),
> GFP_KERNEL);
> > > > > > +	if (!ar0234)
> > > > > > +		return -ENOMEM;
> > > > > > +
> > > > > > +	ret = ar0234_parse_fwnode(ar0234, dev);
> > > > > > +	if (ret)
> > > > > > +		return ret;
> > > > > > +
> > > > > > +	ar0234->regmap = devm_cci_regmap_init_i2c(client, 16);
> > > > > > +	if (IS_ERR(ar0234->regmap))
> > > > > > +		return dev_err_probe(dev, PTR_ERR(ar0234->regmap),
> > > > > > +				     "failed to init CCI");
> > > > > > +
> > > > > > +	v4l2_i2c_subdev_init(&ar0234->sd, client,
> > > > > > +&ar0234_subdev_ops);
> > > > > > +
> > > > > > +	xclk = devm_clk_get(dev, NULL);
> > > > > > +	if (IS_ERR(xclk)) {
> > > > > > +		if (PTR_ERR(xclk) != -EPROBE_DEFER)
> > > > > > +			dev_err(dev, "failed to get xclk %ld", PTR_ERR(xclk));
> > > > > > +		return PTR_ERR(xclk);
> > > > > > +	}
> > > > > > +
> > > > > > +	xclk_freq = clk_get_rate(xclk);
> > > > > > +	if (xclk_freq != AR0234_XCLK_FREQ) {
> > > > > > +		dev_err(dev, "xclk frequency not supported: %d Hz",
> xclk_freq);
> > > > > > +		return -EINVAL;
> > > > > > +	}
> > > > > > +
> > > > > > +	/* Check module identity */
> > > > > > +	ret = ar0234_identify_module(ar0234);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(dev, "failed to find sensor: %d", ret);
> > > > > > +		return ret;
> > > > > > +	}
> > > > > > +
> > > > > > +	ar0234->cur_mode = &supported_modes[0];
> > > > > > +	ret = ar0234_init_controls(ar0234);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "failed to init controls: %d", ret);
> > > > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > > > +	}
> > > > > > +
> > > > > > +	ar0234->sd.internal_ops = &ar0234_internal_ops;
> > > > > > +	ar0234->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > > > +	ar0234->sd.entity.ops = &ar0234_subdev_entity_ops;
> > > > > > +	ar0234->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > > > +
> > > > > > +	ar0234->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > > > +	ret = media_entity_pads_init(&ar0234->sd.entity, 1,
> &ar0234->pad);
> > > > > > +	if (ret) {
> > > > > > +		dev_err(&client->dev, "failed to init entity pads: %d", ret);
> > > > > > +		goto probe_error_v4l2_ctrl_handler_free;
> > > > > > +	}
> > > > > > +
> > > > > > +	ar0234->sd.state_lock = ar0234->ctrl_handler.lock;
> > > > > > +	ret = v4l2_subdev_init_finalize(&ar0234->sd);
> > > > > > +	if (ret < 0) {
> > > > > > +		dev_err(dev, "v4l2 subdev init error: %d", ret);
> > > > > > +		goto probe_error_media_entity_cleanup;
> > > > > > +	}
> > > > > > +
> > > > > > +	/*
> > > > > > +	 * Device is already turned on by i2c-core with ACPI domain
> PM.
> > > > > > +	 * Enable runtime PM and turn off the device.
> > > > > > +	 */
> > > > > > +	pm_runtime_set_active(&client->dev);
> > > > > > +	pm_runtime_enable(&client->dev);
> > > > > > +	pm_runtime_idle(&client->dev);
> > > > > > +
> > > > > > +	ret = v4l2_async_register_subdev_sensor(&ar0234->sd);
> > > > > > +	if (ret < 0) {
> > > > > > +		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
> > > > > > +			ret);
> > > > > > +		goto probe_error_rpm;
> > > > > > +	}
> > > > > > +
> > > > > > +	return 0;
> > > > > > +probe_error_rpm:
> > > > > > +	pm_runtime_disable(&client->dev);
> > > > > > +	v4l2_subdev_cleanup(&ar0234->sd);
> > > > > > +
> > > > > > +probe_error_media_entity_cleanup:
> > > > > > +	media_entity_cleanup(&ar0234->sd.entity);
> > > > > > +
> > > > > > +probe_error_v4l2_ctrl_handler_free:
> > > > > > +	v4l2_ctrl_handler_free(ar0234->sd.ctrl_handler);
> > > > > > +
> > > > > > +	return ret;
> > > > > > +}
> > > > > > +
> > > > > > +static const struct acpi_device_id ar0234_acpi_ids[] = {
> > > > > > +	{ "INTC10C0" },
> > > > > > +	{}
> > > > > > +};
> > > > > > +MODULE_DEVICE_TABLE(acpi, ar0234_acpi_ids);
> > > > > > +
> > > > > > +static struct i2c_driver ar0234_i2c_driver = {
> > > > > > +	.driver = {
> > > > > > +		.name = "ar0234",
> > > > > > +		.acpi_match_table = ACPI_PTR(ar0234_acpi_ids),
> > > > > > +	},
> > > > > > +	.probe = ar0234_probe,
> > > > > > +	.remove = ar0234_remove,
> > > > > > +};
> > > > > > +
> > > > > > +module_i2c_driver(ar0234_i2c_driver);
> > > > > > +
> > > > > > +MODULE_DESCRIPTION("ON Semiconductor ar0234 sensor driver");
> > > > > > +MODULE_AUTHOR("Dongcheng Yan <dongcheng.yan@intel.com>");
> > > > > > +MODULE_AUTHOR("Hao Yao <hao.yao@intel.com>");
> > > > > > +MODULE_LICENSE("GPL");
> 
> --
> Regards,
> 
> Laurent Pinchart