Re: [PATCH] media: v4l: vsp1: Fix offset calculation for plane cropping

[Kieran Bingham <kieran.bingham@ideasonboard.com>]

Quoting Laurent Pinchart (2022-02-28 12:00:58)
> From: Michael Rodin <mrodin@de.adit-jv.com>
> 
> The vertical subsampling factor is currently not considered in the
> offset calculation for plane cropping done in rpf_configure_partition.
> This causes a distortion (shift of the color plane) when formats with
> the vsub factor larger than 1 are used (e.g. NV12, see
> vsp1_video_formats in vsp1_pipe.c). This commit considers vsub factor
> for all planes except plane 0 (luminance).
> 
> Fixes: e5ad37b64de9 ("[media] v4l: vsp1: Add cropping support")
> Signed-off-by: Michael Rodin <mrodin@de.adit-jv.com>
> Signed-off-by: LUU HOAI <hoai.luu.ub@renesas.com>
> 
> Drop generalization of the offset calculation to reduce the binary size.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Looks fine to me, and I now see that the extra tests identify the
failure experienced and resolve it so...

Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>

> ---
>  drivers/media/platform/vsp1/vsp1_rpf.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/platform/vsp1/vsp1_rpf.c b/drivers/media/platform/vsp1/vsp1_rpf.c
> index 85587c1b6a37..75083cb234fe 100644
> --- a/drivers/media/platform/vsp1/vsp1_rpf.c
> +++ b/drivers/media/platform/vsp1/vsp1_rpf.c
> @@ -291,11 +291,11 @@ static void rpf_configure_partition(struct vsp1_entity *entity,
>                      + crop.left * fmtinfo->bpp[0] / 8;
>  
>         if (format->num_planes > 1) {
> +               unsigned int bpl = format->plane_fmt[1].bytesperline;
>                 unsigned int offset;
>  
> -               offset = crop.top * format->plane_fmt[1].bytesperline
> -                      + crop.left / fmtinfo->hsub
> -                      * fmtinfo->bpp[1] / 8;
> +               offset = crop.top / fmtinfo->vsub * bpl
> +                      + crop.left / fmtinfo->hsub * fmtinfo->bpp[1] / 8;
>                 mem.addr[1] += offset;
>                 mem.addr[2] += offset;
>         }
> -- 
> Regards,
> 
> Laurent Pinchart
>