Re: [PATCH v1] media: rcar-vin: Implement `VIDIOC_ENUM_FRMSIZES`

From: Niklas Söderlund

Date: Tue Sep 29 2026 - 10:39:10 EST


Hi Barnabás,

Thanks for your patch,

On 2026-09-29 15:37:20 +0200, Barnabás Pőcze wrote:
> Currently there is no way for applications to query the available frame
> sizes, so implement `VIDIOC_ENUM_FRMSIZES` based on what is allowed in
> `rvin_format_align()`.
>
> Signed-off-by: Barnabás Pőcze <barnabas.pocze+renesas@xxxxxxxxxxxxxxxx>

I'm not super exited about having ` in the patch title. With them
dropped,

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>

> ---
> .../platform/renesas/rcar-vin/rcar-v4l2.c | 70 ++++++++++++++-----
> 1 file changed, 51 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/media/platform/renesas/rcar-vin/rcar-v4l2.c b/drivers/media/platform/renesas/rcar-vin/rcar-v4l2.c
> index 9d45e11898c13..4961d28f42c78 100644
> --- a/drivers/media/platform/renesas/rcar-vin/rcar-v4l2.c
> +++ b/drivers/media/platform/renesas/rcar-vin/rcar-v4l2.c
> @@ -19,6 +19,8 @@
> #include "rcar-vin.h"
>
> #define RVIN_DEFAULT_FORMAT V4L2_PIX_FMT_YUYV
> +#define RVIN_MIN_WIDTH 5
> +#define RVIN_MIN_HEIGHT 2
> #define RVIN_DEFAULT_WIDTH 800
> #define RVIN_DEFAULT_HEIGHT 600
> #define RVIN_DEFAULT_FIELD V4L2_FIELD_NONE
> @@ -187,6 +189,24 @@ static u32 rvin_format_sizeimage(struct v4l2_pix_format *pix)
> }
> }
>
> +static u32 rvin_format_width_alignment(u32 pixelformat)
> +{
> + /* Hardware limits width alignment based on format. */
> + switch (pixelformat) {
> + /* Multiple of 32 (2^5) for NV12/16. */
> + case V4L2_PIX_FMT_NV12:
> + case V4L2_PIX_FMT_NV16:
> + return 5;
> + /* Multiple of 2 (2^1) for YUV. */
> + case V4L2_PIX_FMT_YUYV:
> + case V4L2_PIX_FMT_UYVY:
> + return 1;
> + /* No multiple for RGB. */
> + default:
> + return 0;
> + }
> +}
> +
> static void rvin_format_align(struct rvin_dev *vin, struct v4l2_pix_format *pix)
> {
> u32 walign;
> @@ -208,27 +228,12 @@ static void rvin_format_align(struct rvin_dev *vin, struct v4l2_pix_format *pix)
> break;
> }
>
> - /* Hardware limits width alignment based on format. */
> - switch (pix->pixelformat) {
> - /* Multiple of 32 (2^5) for NV12/16. */
> - case V4L2_PIX_FMT_NV12:
> - case V4L2_PIX_FMT_NV16:
> - walign = 5;
> - break;
> - /* Multiple of 2 (2^1) for YUV. */
> - case V4L2_PIX_FMT_YUYV:
> - case V4L2_PIX_FMT_UYVY:
> - walign = 1;
> - break;
> - /* No multiple for RGB. */
> - default:
> - walign = 0;
> - break;
> - }
> + walign = rvin_format_width_alignment(pix->pixelformat);
>
> /* Limit to VIN capabilities */
> - v4l_bound_align_image(&pix->width, 5, vin->info->max_width, walign,
> - &pix->height, 2, vin->info->max_height, 0, 0);
> + v4l_bound_align_image(&pix->width, RVIN_MIN_WIDTH, vin->info->max_width, walign,
> + &pix->height, RVIN_MIN_HEIGHT, vin->info->max_height, 0,
> + 0);
>
> pix->bytesperline = rvin_format_bytesperline(vin, pix);
> pix->sizeimage = rvin_format_sizeimage(pix);
> @@ -343,6 +348,32 @@ static int rvin_enum_fmt_vid_cap(struct file *file, void *priv,
> return -EINVAL;
> }
>
> +static int rvin_enum_framesizes(struct file *file, void *priv,
> + struct v4l2_frmsizeenum *fsize)
> +{
> + struct rvin_dev *vin = video_drvdata(file);
> + u32 wstep;
> +
> + if (fsize->index != 0)
> + return -EINVAL;
> +
> + if (!rvin_format_from_pixel(vin, fsize->pixel_format))
> + return -EINVAL;
> +
> + fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> +
> + wstep = 1u << rvin_format_width_alignment(fsize->pixel_format);
> + fsize->stepwise.min_width = round_up(RVIN_MIN_WIDTH, wstep);
> + fsize->stepwise.max_width = vin->info->max_width;
> + fsize->stepwise.step_width = wstep;
> +
> + fsize->stepwise.min_height = RVIN_MIN_HEIGHT;
> + fsize->stepwise.max_height = vin->info->max_height;
> + fsize->stepwise.step_height = 1;
> +
> + return 0;
> +}
> +
> static int rvin_remote_rectangle(struct rvin_dev *vin, struct v4l2_rect *rect)
> {
> struct media_pad *pad = media_pad_remote_pad_first(&vin->pad);
> @@ -564,6 +595,7 @@ static const struct v4l2_ioctl_ops rvin_mc_ioctl_ops = {
> .vidioc_g_fmt_vid_cap = rvin_g_fmt_vid_cap,
> .vidioc_s_fmt_vid_cap = rvin_mc_s_fmt_vid_cap,
> .vidioc_enum_fmt_vid_cap = rvin_enum_fmt_vid_cap,
> + .vidioc_enum_framesizes = rvin_enum_framesizes,
>
> .vidioc_g_selection = rvin_g_selection,
> .vidioc_s_selection = rvin_s_selection,
> --
> 2.55.0
>

--
Kind Regards,
Niklas Söderlund