[PATCH v6 5/7] media: mt9m114: Allow set_selection while streaming

[Laurent Pinchart]

Hi Mathis,

Thank you for the patch.

On Thu, May 22, 2025 at 04:35:09PM +0200, Mathis Foerst wrote:
> The current implementation does not apply changes to the crop-
> configuration of the sensor immediately if the sensor is in
> streaming state. The user has to stop and restart the stream for
> the changes to be applied.
> This can be undesirable e.g. in a calibration usecase where the user
> wants to see the impact of his changes in a live video stream.
> Under the condition that the width & height of the cropped image area
> does not change, the changed cropping configuration can be applied to
> the pixel-array immediately without disturbing the IFP.
> 
> Call mt9m114_configure_pa() in mt9m114_pa_set_selection() if the sensor is
> in streaming state and the size of the cropping rectangle didn't change,
> issue a CONFIG_CHANGE to apply the changes immediately.
> 
> Signed-off-by: Mathis Foerst <mathis.foerst at mt.com>
> ---
>  drivers/media/i2c/mt9m114.c | 24 +++++++++++++++++++++---
>  1 file changed, 21 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/i2c/mt9m114.c b/drivers/media/i2c/mt9m114.c
> index 7d39978835fe..e909c1227e51 100644
> --- a/drivers/media/i2c/mt9m114.c
> +++ b/drivers/media/i2c/mt9m114.c
> @@ -1301,11 +1301,14 @@ static int mt9m114_pa_set_selection(struct v4l2_subdev *sd,
>  	struct mt9m114 *sensor = pa_to_mt9m114(sd);
>  	struct v4l2_mbus_framefmt *format;
>  	struct v4l2_rect *crop;
> +	struct v4l2_rect old_crop;
> +	int ret = 0;
>  
>  	if (sel->target != V4L2_SEL_TGT_CROP)
>  		return -EINVAL;
>  
>  	crop = v4l2_subdev_state_get_crop(state, sel->pad);
> +	old_crop = *crop;
>  	format = v4l2_subdev_state_get_format(state, sel->pad);
>  
>  	/*
> @@ -1331,10 +1334,25 @@ static int mt9m114_pa_set_selection(struct v4l2_subdev *sd,
>  	format->width = crop->width;
>  	format->height = crop->height;
>  
> -	if (sel->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> -		mt9m114_pa_ctrl_update_blanking(sensor, format);
> +	if (sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
> +		return ret;
>  
> -	return 0;
> +	mt9m114_pa_ctrl_update_blanking(sensor, format);
> +
> +	/*
> +	 * Apply values immediately if streaming and the selection size did not
> +	 * change.
> +	 */
> +	if (sensor->streaming && old_crop.height == crop->height &&
> +	    old_crop.width == crop->width) {

Changing the width or height of the active crop rectangle should be
disallowed completely during streaming. mt9m114_pa_set_selection().
should return -EBUSY in that case.

> +		ret = mt9m114_configure_pa(sensor, state);
> +		if (ret)
> +			return ret;
> +		// Changing the cropping config requires a CONFIG_CHANGE
> +		ret = mt9m114_set_state(sensor,	MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE);
> +	}
> +
> +	return ret;
>  }
>  
>  static const struct v4l2_subdev_pad_ops mt9m114_pa_pad_ops = {

-- 
Regards,

Laurent Pinchart