diff mbox series

[2/2] media: ov2740: Add support for external clock

Message ID 20231115123817.196252-3-hdegoede@redhat.com (mailing list archive)
State Superseded
Delegated to: Sakari Ailus
Headers
Series media: ov2740: Add support for reset GPIO and external clock |

Commit Message

Hans de Goede Nov. 15, 2023, 12:38 p.m. UTC 
On some ACPI platforms, such as Chromebooks the ACPI methods to
change the power-state (_PS0 and _PS3) fully take care of powering
on/off the sensor.

On other ACPI platforms, such as e.g. various ThinkPad models with
IPU6 + ov2740 sensor, the sensor driver must control the reset GPIO
and the sensor's clock itself.

Add support for having the driver control an optional clock.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/media/i2c/ov2740.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

Comments

Bingbu Cao Nov. 20, 2023, 4:06 a.m. UTC | #1 
Hans,

On 11/15/23 8:38 PM, Hans de Goede wrote:
> On some ACPI platforms, such as Chromebooks the ACPI methods to
> change the power-state (_PS0 and _PS3) fully take care of powering
> on/off the sensor.
> 
> On other ACPI platforms, such as e.g. various ThinkPad models with
> IPU6 + ov2740 sensor, the sensor driver must control the reset GPIO
> and the sensor's clock itself.
> 
> Add support for having the driver control an optional clock.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/media/i2c/ov2740.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
> index e5f9569a229d..0a87d0920eb8 100644
> --- a/drivers/media/i2c/ov2740.c
> +++ b/drivers/media/i2c/ov2740.c
> @@ -3,6 +3,7 @@
>  
>  #include <asm/unaligned.h>
>  #include <linux/acpi.h>
> +#include <linux/clk.h>
>  #include <linux/delay.h>
>  #include <linux/gpio/consumer.h>
>  #include <linux/i2c.h>
> @@ -336,6 +337,7 @@ struct ov2740 {
>  
>  	/* GPIOs, clocks */
>  	struct gpio_desc *reset_gpio;
> +	struct clk *clk;
>  
>  	/* Current mode */
>  	const struct ov2740_mode *cur_mode;
> @@ -1068,6 +1070,7 @@ static int ov2740_suspend(struct device *dev)
>  	struct ov2740 *ov2740 = to_ov2740(sd);
>  
>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
> +	clk_disable_unprepare(ov2740->clk);
>  	return 0;
>  }
>  
> @@ -1075,6 +1078,11 @@ static int ov2740_resume(struct device *dev)
>  {
>  	struct v4l2_subdev *sd = dev_get_drvdata(dev);
>  	struct ov2740 *ov2740 = to_ov2740(sd);
> +	int ret;
> +
> +	ret = clk_prepare_enable(ov2740->clk);
> +	if (ret)
> +		return ret;
>  
>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
>  	msleep(20);
> @@ -1102,6 +1110,10 @@ static int ov2740_probe(struct i2c_client *client)
>  		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
>  				     "failed to get reset GPIO\n");
>  
> +	ov2740->clk = devm_clk_get_optional(dev, "clk");
> +	if (IS_ERR(ov2740->clk))
> +		return dev_err_probe(dev, PTR_ERR(ov2740->clk), "failed to get clock\n");
> +

I am not very sure that the 80-char rule is still valid for checkpatch.pl.


>  	v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
>  	full_power = acpi_dev_state_d0(&client->dev);
>  	if (full_power) {
>

Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>
Hans de Goede Nov. 20, 2023, 10 a.m. UTC | #2 
Hi Bingbu,

On 11/20/23 05:06, Bingbu Cao wrote:
> 
> Hans,
> 
> On 11/15/23 8:38 PM, Hans de Goede wrote:
>> On some ACPI platforms, such as Chromebooks the ACPI methods to
>> change the power-state (_PS0 and _PS3) fully take care of powering
>> on/off the sensor.
>>
>> On other ACPI platforms, such as e.g. various ThinkPad models with
>> IPU6 + ov2740 sensor, the sensor driver must control the reset GPIO
>> and the sensor's clock itself.
>>
>> Add support for having the driver control an optional clock.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>>  drivers/media/i2c/ov2740.c | 12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
>> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
>> index e5f9569a229d..0a87d0920eb8 100644
>> --- a/drivers/media/i2c/ov2740.c
>> +++ b/drivers/media/i2c/ov2740.c
>> @@ -3,6 +3,7 @@
>>  
>>  #include <asm/unaligned.h>
>>  #include <linux/acpi.h>
>> +#include <linux/clk.h>
>>  #include <linux/delay.h>
>>  #include <linux/gpio/consumer.h>
>>  #include <linux/i2c.h>
>> @@ -336,6 +337,7 @@ struct ov2740 {
>>  
>>  	/* GPIOs, clocks */
>>  	struct gpio_desc *reset_gpio;
>> +	struct clk *clk;
>>  
>>  	/* Current mode */
>>  	const struct ov2740_mode *cur_mode;
>> @@ -1068,6 +1070,7 @@ static int ov2740_suspend(struct device *dev)
>>  	struct ov2740 *ov2740 = to_ov2740(sd);
>>  
>>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
>> +	clk_disable_unprepare(ov2740->clk);
>>  	return 0;
>>  }
>>  
>> @@ -1075,6 +1078,11 @@ static int ov2740_resume(struct device *dev)
>>  {
>>  	struct v4l2_subdev *sd = dev_get_drvdata(dev);
>>  	struct ov2740 *ov2740 = to_ov2740(sd);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(ov2740->clk);
>> +	if (ret)
>> +		return ret;
>>  
>>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
>>  	msleep(20);
>> @@ -1102,6 +1110,10 @@ static int ov2740_probe(struct i2c_client *client)
>>  		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
>>  				     "failed to get reset GPIO\n");
>>  
>> +	ov2740->clk = devm_clk_get_optional(dev, "clk");
>> +	if (IS_ERR(ov2740->clk))
>> +		return dev_err_probe(dev, PTR_ERR(ov2740->clk), "failed to get clock\n");
>> +
> 
> I am not very sure that the 80-char rule is still valid for checkpatch.pl.

checkpatch.pl defaults to allowing longer lines (<100 chars) now,
but you are right that the linux-media maintainers prefer 80.

Still there is an exception to not split strings running
over the limit and this line ends with a string,
so I think that this is fine.

Regards,

Hans
Sakari Ailus Nov. 20, 2023, 4:32 p.m. UTC | #3 
Hi Hans,

On Mon, Nov 20, 2023 at 11:00:14AM +0100, Hans de Goede wrote:
> Hi Bingbu,
> 
> On 11/20/23 05:06, Bingbu Cao wrote:
> > 
> > Hans,
> > 
> > On 11/15/23 8:38 PM, Hans de Goede wrote:
> >> On some ACPI platforms, such as Chromebooks the ACPI methods to
> >> change the power-state (_PS0 and _PS3) fully take care of powering
> >> on/off the sensor.
> >>
> >> On other ACPI platforms, such as e.g. various ThinkPad models with
> >> IPU6 + ov2740 sensor, the sensor driver must control the reset GPIO
> >> and the sensor's clock itself.
> >>
> >> Add support for having the driver control an optional clock.
> >>
> >> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> >> ---
> >>  drivers/media/i2c/ov2740.c | 12 ++++++++++++
> >>  1 file changed, 12 insertions(+)
> >>
> >> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
> >> index e5f9569a229d..0a87d0920eb8 100644
> >> --- a/drivers/media/i2c/ov2740.c
> >> +++ b/drivers/media/i2c/ov2740.c
> >> @@ -3,6 +3,7 @@
> >>  
> >>  #include <asm/unaligned.h>
> >>  #include <linux/acpi.h>
> >> +#include <linux/clk.h>
> >>  #include <linux/delay.h>
> >>  #include <linux/gpio/consumer.h>
> >>  #include <linux/i2c.h>
> >> @@ -336,6 +337,7 @@ struct ov2740 {
> >>  
> >>  	/* GPIOs, clocks */
> >>  	struct gpio_desc *reset_gpio;
> >> +	struct clk *clk;
> >>  
> >>  	/* Current mode */
> >>  	const struct ov2740_mode *cur_mode;
> >> @@ -1068,6 +1070,7 @@ static int ov2740_suspend(struct device *dev)
> >>  	struct ov2740 *ov2740 = to_ov2740(sd);
> >>  
> >>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
> >> +	clk_disable_unprepare(ov2740->clk);
> >>  	return 0;
> >>  }
> >>  
> >> @@ -1075,6 +1078,11 @@ static int ov2740_resume(struct device *dev)
> >>  {
> >>  	struct v4l2_subdev *sd = dev_get_drvdata(dev);
> >>  	struct ov2740 *ov2740 = to_ov2740(sd);
> >> +	int ret;
> >> +
> >> +	ret = clk_prepare_enable(ov2740->clk);
> >> +	if (ret)
> >> +		return ret;
> >>  
> >>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
> >>  	msleep(20);
> >> @@ -1102,6 +1110,10 @@ static int ov2740_probe(struct i2c_client *client)
> >>  		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
> >>  				     "failed to get reset GPIO\n");
> >>  
> >> +	ov2740->clk = devm_clk_get_optional(dev, "clk");
> >> +	if (IS_ERR(ov2740->clk))
> >> +		return dev_err_probe(dev, PTR_ERR(ov2740->clk), "failed to get clock\n");
> >> +
> > 
> > I am not very sure that the 80-char rule is still valid for checkpatch.pl.
> 
> checkpatch.pl defaults to allowing longer lines (<100 chars) now,
> but you are right that the linux-media maintainers prefer 80.
> 
> Still there is an exception to not split strings running
> over the limit and this line ends with a string,
> so I think that this is fine.

The rule is not to split strings in order to satisfy alignment rules. IOW
the line should be wrapped before the string. :-)
Hans de Goede Nov. 23, 2023, 9:57 a.m. UTC | #4 
Hi,

On 11/20/23 17:32, Sakari Ailus wrote:
> Hi Hans,
> 
> On Mon, Nov 20, 2023 at 11:00:14AM +0100, Hans de Goede wrote:
>> Hi Bingbu,
>>
>> On 11/20/23 05:06, Bingbu Cao wrote:
>>>
>>> Hans,
>>>
>>> On 11/15/23 8:38 PM, Hans de Goede wrote:
>>>> On some ACPI platforms, such as Chromebooks the ACPI methods to
>>>> change the power-state (_PS0 and _PS3) fully take care of powering
>>>> on/off the sensor.
>>>>
>>>> On other ACPI platforms, such as e.g. various ThinkPad models with
>>>> IPU6 + ov2740 sensor, the sensor driver must control the reset GPIO
>>>> and the sensor's clock itself.
>>>>
>>>> Add support for having the driver control an optional clock.
>>>>
>>>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>>>> ---
>>>>  drivers/media/i2c/ov2740.c | 12 ++++++++++++
>>>>  1 file changed, 12 insertions(+)
>>>>
>>>> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
>>>> index e5f9569a229d..0a87d0920eb8 100644
>>>> --- a/drivers/media/i2c/ov2740.c
>>>> +++ b/drivers/media/i2c/ov2740.c
>>>> @@ -3,6 +3,7 @@
>>>>  
>>>>  #include <asm/unaligned.h>
>>>>  #include <linux/acpi.h>
>>>> +#include <linux/clk.h>
>>>>  #include <linux/delay.h>
>>>>  #include <linux/gpio/consumer.h>
>>>>  #include <linux/i2c.h>
>>>> @@ -336,6 +337,7 @@ struct ov2740 {
>>>>  
>>>>  	/* GPIOs, clocks */
>>>>  	struct gpio_desc *reset_gpio;
>>>> +	struct clk *clk;
>>>>  
>>>>  	/* Current mode */
>>>>  	const struct ov2740_mode *cur_mode;
>>>> @@ -1068,6 +1070,7 @@ static int ov2740_suspend(struct device *dev)
>>>>  	struct ov2740 *ov2740 = to_ov2740(sd);
>>>>  
>>>>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
>>>> +	clk_disable_unprepare(ov2740->clk);
>>>>  	return 0;
>>>>  }
>>>>  
>>>> @@ -1075,6 +1078,11 @@ static int ov2740_resume(struct device *dev)
>>>>  {
>>>>  	struct v4l2_subdev *sd = dev_get_drvdata(dev);
>>>>  	struct ov2740 *ov2740 = to_ov2740(sd);
>>>> +	int ret;
>>>> +
>>>> +	ret = clk_prepare_enable(ov2740->clk);
>>>> +	if (ret)
>>>> +		return ret;
>>>>  
>>>>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
>>>>  	msleep(20);
>>>> @@ -1102,6 +1110,10 @@ static int ov2740_probe(struct i2c_client *client)
>>>>  		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
>>>>  				     "failed to get reset GPIO\n");
>>>>  
>>>> +	ov2740->clk = devm_clk_get_optional(dev, "clk");
>>>> +	if (IS_ERR(ov2740->clk))
>>>> +		return dev_err_probe(dev, PTR_ERR(ov2740->clk), "failed to get clock\n");
>>>> +
>>>
>>> I am not very sure that the 80-char rule is still valid for checkpatch.pl.
>>
>> checkpatch.pl defaults to allowing longer lines (<100 chars) now,
>> but you are right that the linux-media maintainers prefer 80.
>>
>> Still there is an exception to not split strings running
>> over the limit and this line ends with a string,
>> so I think that this is fine.
> 
> The rule is not to split strings in order to satisfy alignment rules. IOW
> the line should be wrapped before the string. :-)

Ok, will fix for v2.

Regards,

Hans
diff mbox series

Patch

diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
index e5f9569a229d..0a87d0920eb8 100644
--- a/drivers/media/i2c/ov2740.c
+++ b/drivers/media/i2c/ov2740.c
@@ -3,6 +3,7 @@ 
 
 #include <asm/unaligned.h>
 #include <linux/acpi.h>
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
@@ -336,6 +337,7 @@  struct ov2740 {
 
 	/* GPIOs, clocks */
 	struct gpio_desc *reset_gpio;
+	struct clk *clk;
 
 	/* Current mode */
 	const struct ov2740_mode *cur_mode;
@@ -1068,6 +1070,7 @@  static int ov2740_suspend(struct device *dev)
 	struct ov2740 *ov2740 = to_ov2740(sd);
 
 	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
+	clk_disable_unprepare(ov2740->clk);
 	return 0;
 }
 
@@ -1075,6 +1078,11 @@  static int ov2740_resume(struct device *dev)
 {
 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
 	struct ov2740 *ov2740 = to_ov2740(sd);
+	int ret;
+
+	ret = clk_prepare_enable(ov2740->clk);
+	if (ret)
+		return ret;
 
 	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
 	msleep(20);
@@ -1102,6 +1110,10 @@  static int ov2740_probe(struct i2c_client *client)
 		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
 				     "failed to get reset GPIO\n");
 
+	ov2740->clk = devm_clk_get_optional(dev, "clk");
+	if (IS_ERR(ov2740->clk))
+		return dev_err_probe(dev, PTR_ERR(ov2740->clk), "failed to get clock\n");
+
 	v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
 	full_power = acpi_dev_state_d0(&client->dev);
 	if (full_power) {