Re: [PATCH v2] media: rcar-vin: Update crop and compose settings for every s_fmt call

[Hans Verkuil <hverkuil-cisco@xs4all.nl>]

On 13/09/2020 20:21, Lad Prabhakar wrote:
> The crop and compose settings for VIN in non mc mode werent updated
> in s_fmt call this resulted in captured images being clipped.
> 
> With the below sequence on the third capture where size is set to
> 640x480 resulted in clipped image of size 320x240.
> 
> high(640x480) -> low (320x240) -> high (640x480)
> 
> This patch makes sure the VIN crop and compose settings are updated.

I'm not sure the original behavior was wrong at all.

When calling S_FMT(320x240) it should force the crop and compose rectangles
into 320x240, but when calling S_FMT(640x480) the crop and compose rectangles
do not need to be modified and are kept. It is up to userspace to update those
crop/compose rectangles.

Calling S_FMT must, however, update the crop/compose bounds/default rectangles
where applicable.

Note that the crop coordinates are against the video source resolution, *not*
the format width/height. So this patch is definitely wrong in that respect.

Regards,

	Hans

> 
> Fixes: 104464f573d ("media: rcar-vin: Do not reset the crop and compose rectangles in s_fmt")
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> Changes for v2:
> * Dropped redundant code mapping crop and compose rects
> 
> v1 - https://lkml.org/lkml/2020/7/31/364
> ---
>  drivers/media/platform/rcar-vin/rcar-v4l2.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c b/drivers/media/platform/rcar-vin/rcar-v4l2.c
> index 0e066bba747e..1bd59a8453b4 100644
> --- a/drivers/media/platform/rcar-vin/rcar-v4l2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c
> @@ -305,7 +305,7 @@ static int rvin_s_fmt_vid_cap(struct file *file, void *priv,
>  			      struct v4l2_format *f)
>  {
>  	struct rvin_dev *vin = video_drvdata(file);
> -	struct v4l2_rect fmt_rect, src_rect;
> +	struct v4l2_rect src_rect;
>  	int ret;
>  
>  	if (vb2_is_busy(&vin->queue))
> @@ -317,14 +317,11 @@ static int rvin_s_fmt_vid_cap(struct file *file, void *priv,
>  		return ret;
>  
>  	vin->format = f->fmt.pix;
> -
> -	fmt_rect.top = 0;
> -	fmt_rect.left = 0;
> -	fmt_rect.width = vin->format.width;
> -	fmt_rect.height = vin->format.height;
> -
> -	v4l2_rect_map_inside(&vin->crop, &src_rect);
> -	v4l2_rect_map_inside(&vin->compose, &fmt_rect);
> +	vin->crop.top = 0;
> +	vin->crop.left = 0;
> +	vin->crop.width = vin->format.width;
> +	vin->crop.height = vin->format.height;
> +	vin->compose = vin->crop;
>  	vin->src_rect = src_rect;
>  
>  	return 0;
>