Re: [PATCH] media: stm32-dcmi: add g/s_parm framerate support

[Hans Verkuil]

On 02/07/2018 06:43 PM, Hugues Fruchet wrote:
> Add g/s_parm framerate support by calling subdev
> g/s_frame_interval ops.
> This allows user to control sensor framerate by
> calling ioctl G/S_PARM.
> 
> Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
> ---
>  drivers/media/platform/stm32/stm32-dcmi.c | 49 +++++++++++++++++++++++++++++++
>  1 file changed, 49 insertions(+)
> 
> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
> index ab555d4..8197554 100644
> --- a/drivers/media/platform/stm32/stm32-dcmi.c
> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
> @@ -1151,6 +1151,52 @@ static int dcmi_enum_framesizes(struct file *file, void *fh,
>  	return 0;
>  }
>  
> +static int dcmi_g_parm(struct file *file, void *priv,
> +		       struct v4l2_streamparm *p)
> +{
> +	struct stm32_dcmi *dcmi = video_drvdata(file);
> +	struct v4l2_subdev_frame_interval ival = { 0 };
> +	int ret;
> +
> +	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
> +		return -EINVAL;
> +
> +	p->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
> +	ret = v4l2_subdev_call(dcmi->entity.subdev, video,
> +			       g_frame_interval, &ival);
> +	if (ret)
> +		return ret;
> +
> +	p->parm.capture.timeperframe = ival.interval;
> +
> +	return ret;
> +}

This function and the next can be simplified by using the help functions
introduced here:

https://git.linuxtv.org/hverkuil/media_tree.git/log/?h=parm

I'll make a pull request for this later this week, so it's probably a good
idea to base your code on this as well.

Regards,

	Hans

> +
> +static int dcmi_s_parm(struct file *file, void *priv,
> +		       struct v4l2_streamparm *p)
> +{
> +	struct stm32_dcmi *dcmi = video_drvdata(file);
> +	struct v4l2_subdev_frame_interval ival = {
> +		0,
> +		p->parm.capture.timeperframe
> +	};
> +	int ret;
> +
> +	if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
> +		return -EINVAL;
> +
> +	memset(&p->parm, 0, sizeof(p->parm));
> +	p->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
> +	ret = v4l2_subdev_call(dcmi->entity.subdev, video,
> +			       s_frame_interval, &ival);
> +	if (ret)
> +		return ret;
> +
> +	p->parm.capture.timeperframe = ival.interval;
> +
> +	return ret;
> +}
> +
>  static int dcmi_enum_frameintervals(struct file *file, void *fh,
>  				    struct v4l2_frmivalenum *fival)
>  {
> @@ -1253,6 +1299,9 @@ static int dcmi_release(struct file *file)
>  	.vidioc_g_input			= dcmi_g_input,
>  	.vidioc_s_input			= dcmi_s_input,
>  
> +	.vidioc_g_parm			= dcmi_g_parm,
> +	.vidioc_s_parm			= dcmi_s_parm,
> +
>  	.vidioc_enum_framesizes		= dcmi_enum_framesizes,
>  	.vidioc_enum_frameintervals	= dcmi_enum_frameintervals,
>  
>