Hi Hans,
Thank you for the patch.
On Wed, Dec 24, 2025 at 01:31:22PM +0100, Hans de Goede wrote:
> Drop the start-, stop-streaming sequence from initialize.
>
> When streaming is started with a runtime-suspended sensor,
> mt9m114_start_streaming() will runtime-resume the sensor which calls
> mt9m114_initialize() immediately followed by calling
> mt9m114_set_state(ENTER_CONFIG_CHANGE).
>
> This results in the following state changes in quick succession:
>
> mt9m114_set_state(ENTER_CONFIG_CHANGE) -> transitions to STREAMING
> mt9m114_set_state(ENTER_SUSPEND) -> transitions to SUSPENDED
> mt9m114_set_state(ENTER_CONFIG_CHANGE) -> transitions to STREAMING
>
> these quick state changes confuses the CSI receiver on atomisp devices
> causing streaming to not work.
>
> Drop the state changes from mt9m114_initialize() and move
> the mt9m114_initialize() call to mt9m114_start_streaming()
> so that only a single mt9m114_set_state(ENTER_CONFIG_CHANGE) call
> is made when streaming is started with a runtime-suspend sensor.
>
> Signed-off-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
> ---
> Changes in v4:
> - Move the mt9m114_initialize() call to mt9m114_start_streaming()
> and drop the config_change_pending flag
> ---
> drivers/media/i2c/mt9m114.c | 33 +++++++--------------------------
> 1 file changed, 7 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/media/i2c/mt9m114.c b/drivers/media/i2c/mt9m114.c
> index 447a5eb34a6137a8e87bd119401571b5592fc77d..41e98f719a23045293ee47d8980675510a142afa 100644
> --- a/drivers/media/i2c/mt9m114.c
> +++ b/drivers/media/i2c/mt9m114.c
> @@ -789,14 +789,6 @@ static int mt9m114_initialize(struct mt9m114 *sensor)
> if (ret < 0)
> return ret;
>
> - ret = mt9m114_set_state(sensor, MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE);
> - if (ret < 0)
> - return ret;
> -
> - ret = mt9m114_set_state(sensor, MT9M114_SYS_STATE_ENTER_SUSPEND);
> - if (ret < 0)
> - return ret;
> -
> return 0;
> }
>
> @@ -967,6 +959,10 @@ static int mt9m114_start_streaming(struct mt9m114 *sensor,
> if (ret)
> return ret;
>
> + ret = mt9m114_initialize(sensor);
> + if (ret)
> + goto error;
> +
> ret = mt9m114_configure_ifp(sensor, ifp_state);
> if (ret)
> goto error;
> @@ -2318,19 +2314,8 @@ static int __maybe_unused mt9m114_runtime_resume(struct device *dev)
> {
> struct v4l2_subdev *sd = dev_get_drvdata(dev);
> struct mt9m114 *sensor = ifp_to_mt9m114(sd);
> - int ret;
>
> - ret = mt9m114_power_on(sensor);
> - if (ret)
> - return ret;
> -
> - ret = mt9m114_initialize(sensor);
> - if (ret) {
> - mt9m114_power_off(sensor);
> - return ret;
> - }
> -
> - return 0;
> + return mt9m114_power_on(sensor);
> }
>
> static int __maybe_unused mt9m114_runtime_suspend(struct device *dev)
> @@ -2562,8 +2547,8 @@ static int mt9m114_probe(struct i2c_client *client)
> /*
> * Identify the sensor. The driver supports runtime PM, but needs to
> * work when runtime PM is disabled in the kernel. To that end, power
> - * the sensor on manually here, and initialize it after identification
> - * to reach the same state as if resumed through runtime PM.
> + * the sensor on manually here and identify it to reach the same state
s/and identify it //
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> + * as if resumed through runtime PM.
> */
> ret = mt9m114_power_on(sensor);
> if (ret < 0) {
> @@ -2575,10 +2560,6 @@ static int mt9m114_probe(struct i2c_client *client)
> if (ret < 0)
> goto error_power_off;
>
> - ret = mt9m114_initialize(sensor);
> - if (ret < 0)
> - goto error_power_off;
> -
> /*
> * Enable runtime PM with autosuspend. As the device has been powered
> * manually, mark it as active, and increase the usage count without
--
Regards,
Laurent Pinchart