[1/2] media: ov2740: Add support for reset GPIO
Commit Message
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 reset GPIO.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/media/i2c/ov2740.c | 48 ++++++++++++++++++++++++++++++++++++--
1 file changed, 46 insertions(+), 2 deletions(-)
Comments
Hans,
Thanks for your patch.
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 reset GPIO.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> drivers/media/i2c/ov2740.c | 48 ++++++++++++++++++++++++++++++++++++--
> 1 file changed, 46 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
> index 24e468485fbf..e5f9569a229d 100644
> --- a/drivers/media/i2c/ov2740.c
> +++ b/drivers/media/i2c/ov2740.c
> @@ -4,6 +4,7 @@
> #include <asm/unaligned.h>
> #include <linux/acpi.h>
> #include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/i2c.h>
> #include <linux/module.h>
> #include <linux/pm_runtime.h>
> @@ -333,6 +334,9 @@ struct ov2740 {
> struct v4l2_ctrl *hblank;
> struct v4l2_ctrl *exposure;
>
> + /* GPIOs, clocks */
It looks like the 'clock' should be in another one (2/2), :).
> + struct gpio_desc *reset_gpio;
> +
> /* Current mode */
> const struct ov2740_mode *cur_mode;
>
> @@ -1058,6 +1062,26 @@ static int ov2740_register_nvmem(struct i2c_client *client,
> return 0;
> }
>
> +static int ov2740_suspend(struct device *dev)
> +{
> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> + struct ov2740 *ov2740 = to_ov2740(sd);
> +
> + gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
> + return 0;
> +}
> +
> +static int ov2740_resume(struct device *dev)
> +{
> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> + struct ov2740 *ov2740 = to_ov2740(sd);
> +
> + gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
> + msleep(20);
I remember that usleep_range() is prefered for <=20ms.
> +
> + return 0;
> +}
> +
> static int ov2740_probe(struct i2c_client *client)
> {
> struct device *dev = &client->dev;
> @@ -1073,12 +1097,24 @@ static int ov2740_probe(struct i2c_client *client)
> if (!ov2740)
> return -ENOMEM;
>
> + ov2740->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
> + if (IS_ERR(ov2740->reset_gpio))
> + return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
> + "failed to get reset GPIO\n");
> +
> v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
> full_power = acpi_dev_state_d0(&client->dev);
> if (full_power) {
> - ret = ov2740_identify_module(ov2740);
> + /* ACPI does not always clear the reset GPIO / enable the clock */
> + ret = ov2740_resume(dev);
> if (ret)
> - return dev_err_probe(dev, ret, "failed to find sensor\n");
> + return dev_err_probe(dev, ret, "failed to power on sensor\n");
> +
> + ret = ov2740_identify_module(ov2740);
> + if (ret) {
> + dev_err_probe(dev, ret, "failed to find sensor\n");
> + goto probe_error_power_off;
> + }
> }
>
> ov2740->cur_mode = &supported_modes[0];
> @@ -1132,9 +1168,16 @@ static int ov2740_probe(struct i2c_client *client)
> probe_error_v4l2_ctrl_handler_free:
> v4l2_ctrl_handler_free(ov2740->sd.ctrl_handler);
>
> +probe_error_power_off:
> + if (full_power)
> + ov2740_suspend(dev);
> +
> return ret;
> }
>
> +static DEFINE_RUNTIME_DEV_PM_OPS(ov2740_pm_ops, ov2740_suspend, ov2740_resume,
> + NULL);
> +
> static const struct acpi_device_id ov2740_acpi_ids[] = {
> {"INT3474"},
> {}
> @@ -1146,6 +1189,7 @@ static struct i2c_driver ov2740_i2c_driver = {
> .driver = {
> .name = "ov2740",
> .acpi_match_table = ov2740_acpi_ids,
> + .pm = pm_sleep_ptr(&ov2740_pm_ops),
> },
> .probe = ov2740_probe,
> .remove = ov2740_remove,
>
Except the minor comment.
Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>
Hi Bingbu,
Thank you for the review!
On 11/20/23 05:04, Bingbu Cao wrote:
>
> Hans,
>
> Thanks for your patch.
>
> 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 reset GPIO.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> drivers/media/i2c/ov2740.c | 48 ++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 46 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
>> index 24e468485fbf..e5f9569a229d 100644
>> --- a/drivers/media/i2c/ov2740.c
>> +++ b/drivers/media/i2c/ov2740.c
>> @@ -4,6 +4,7 @@
>> #include <asm/unaligned.h>
>> #include <linux/acpi.h>
>> #include <linux/delay.h>
>> +#include <linux/gpio/consumer.h>
>> #include <linux/i2c.h>
>> #include <linux/module.h>
>> #include <linux/pm_runtime.h>
>> @@ -333,6 +334,9 @@ struct ov2740 {
>> struct v4l2_ctrl *hblank;
>> struct v4l2_ctrl *exposure;
>>
>> + /* GPIOs, clocks */
>
> It looks like the 'clock' should be in another one (2/2), :).
This was intentional to avoid churn in the form of
immediately changing the comment in the second patch :)
>> + struct gpio_desc *reset_gpio;
>> +
>> /* Current mode */
>> const struct ov2740_mode *cur_mode;
>>
>> @@ -1058,6 +1062,26 @@ static int ov2740_register_nvmem(struct i2c_client *client,
>> return 0;
>> }
>>
>> +static int ov2740_suspend(struct device *dev)
>> +{
>> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
>> + struct ov2740 *ov2740 = to_ov2740(sd);
>> +
>> + gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
>> + return 0;
>> +}
>> +
>> +static int ov2740_resume(struct device *dev)
>> +{
>> + struct v4l2_subdev *sd = dev_get_drvdata(dev);
>> + struct ov2740 *ov2740 = to_ov2740(sd);
>> +
>> + gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
>> + msleep(20);
>
> I remember that usleep_range() is prefered for <=20ms.
I think that only applies to msleep <= 10ms, at least
check-patch is happy with this and I know it complains
about too short msleep() calls.
Regards,
Hans
@@ -4,6 +4,7 @@
#include <asm/unaligned.h>
#include <linux/acpi.h>
#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
@@ -333,6 +334,9 @@ struct ov2740 {
struct v4l2_ctrl *hblank;
struct v4l2_ctrl *exposure;
+ /* GPIOs, clocks */
+ struct gpio_desc *reset_gpio;
+
/* Current mode */
const struct ov2740_mode *cur_mode;
@@ -1058,6 +1062,26 @@ static int ov2740_register_nvmem(struct i2c_client *client,
return 0;
}
+static int ov2740_suspend(struct device *dev)
+{
+ struct v4l2_subdev *sd = dev_get_drvdata(dev);
+ struct ov2740 *ov2740 = to_ov2740(sd);
+
+ gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
+ return 0;
+}
+
+static int ov2740_resume(struct device *dev)
+{
+ struct v4l2_subdev *sd = dev_get_drvdata(dev);
+ struct ov2740 *ov2740 = to_ov2740(sd);
+
+ gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
+ msleep(20);
+
+ return 0;
+}
+
static int ov2740_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
@@ -1073,12 +1097,24 @@ static int ov2740_probe(struct i2c_client *client)
if (!ov2740)
return -ENOMEM;
+ ov2740->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ov2740->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
+ "failed to get reset GPIO\n");
+
v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
full_power = acpi_dev_state_d0(&client->dev);
if (full_power) {
- ret = ov2740_identify_module(ov2740);
+ /* ACPI does not always clear the reset GPIO / enable the clock */
+ ret = ov2740_resume(dev);
if (ret)
- return dev_err_probe(dev, ret, "failed to find sensor\n");
+ return dev_err_probe(dev, ret, "failed to power on sensor\n");
+
+ ret = ov2740_identify_module(ov2740);
+ if (ret) {
+ dev_err_probe(dev, ret, "failed to find sensor\n");
+ goto probe_error_power_off;
+ }
}
ov2740->cur_mode = &supported_modes[0];
@@ -1132,9 +1168,16 @@ static int ov2740_probe(struct i2c_client *client)
probe_error_v4l2_ctrl_handler_free:
v4l2_ctrl_handler_free(ov2740->sd.ctrl_handler);
+probe_error_power_off:
+ if (full_power)
+ ov2740_suspend(dev);
+
return ret;
}
+static DEFINE_RUNTIME_DEV_PM_OPS(ov2740_pm_ops, ov2740_suspend, ov2740_resume,
+ NULL);
+
static const struct acpi_device_id ov2740_acpi_ids[] = {
{"INT3474"},
{}
@@ -1146,6 +1189,7 @@ static struct i2c_driver ov2740_i2c_driver = {
.driver = {
.name = "ov2740",
.acpi_match_table = ov2740_acpi_ids,
+ .pm = pm_sleep_ptr(&ov2740_pm_ops),
},
.probe = ov2740_probe,
.remove = ov2740_remove,