Re: [PATCH 1/4] media: rcar-isp: ispcore: Honour requested bytesperline on RAW input

[Barnabás Pőcze]

Hi

2026. 10. 19. 21:35 keltezéssel, Niklas Söderlund írta:
> From: Yuya Hamamachi <yuya.hamamachi.sx@xxxxxxxxxxx>
>
> The RAW input video device always overwrote the bytesperline requested
> by userspace with width * bpp. The input buffers are however shared with
> the VIN, which may use a larger line stride (for example 3296 instead of
> 3280 bytes for a 1640 pixel wide 10 bit image). The dmabuf exported by
> the ISP was then smaller than the VIN buffer size, and queueing it to
> the VIN failed with -EINVAL:
>
>    __prepare_dmabuf: invalid dmabuf length 4042752 for plane 0,
>    minimum length 4060672
>
> Use the requested bytesperline if it is larger than the minimum.
>
> Signed-off-by: Yuya Hamamachi <yuya.hamamachi.sx@xxxxxxxxxxx>
> [Niklas: Use max(min(..)) instead of if statement]
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
>   drivers/media/platform/renesas/rcar-isp/core-io.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/renesas/rcar-isp/core-io.c b/drivers/media/platform/renesas/rcar-isp/core-io.c
> index b60b91f43d42..badde72352c1 100644
> --- a/drivers/media/platform/renesas/rcar-isp/core-io.c
> +++ b/drivers/media/platform/renesas/rcar-isp/core-io.c
> @@ -5,6 +5,8 @@
>    * Copyright (C) 2026 Ragnatech AB
>    */
>   
> +#include <linux/sizes.h>
> +
>   #include <media/v4l2-ctrls.h>
>   #include <media/v4l2-event.h>
>   #include <media/v4l2-ioctl.h>
> @@ -335,6 +337,7 @@ static void risp_io_input_try_format(struct rcar_isp_core_io *io,
>   				     struct v4l2_pix_format_mplane *pix)
>   {
>   	unsigned int bpp = 0;
> +	unsigned int bpl;
>   
>   	v4l_bound_align_image(&pix->width, RISP_MIN_WIDTH, RISP_MAX_WIDTH, RISP_SIZE_ALIGNMENT,
>   			      &pix->height, RISP_MIN_HEIGHT, RISP_MAX_HEIGHT, RISP_SIZE_ALIGNMENT,
> @@ -352,11 +355,17 @@ static void risp_io_input_try_format(struct rcar_isp_core_io *io,
>   		bpp = risp_io_input_formats[0].bpp;
>   	}
>   
> +	/*
> +	 * Honour the line stride requested by userspace, the buffers are
> +	 * shared with the VIN which may use a larger stride than the minimum.
> +	 */
> +	bpl = max(pix->width * bpp, min(pix->plane_fmt[0].bytesperline, SZ_64K));

  clamp(pix->plane_fmt[0].bytesperline, pix->width * bpp, SZ_64K)

?

And does the device really accept any value between these two limits?


> +
>   	pix->field = V4L2_FIELD_NONE;
>   	pix->colorspace = V4L2_COLORSPACE_RAW;
>   
>   	pix->num_planes = 1;
> -	pix->plane_fmt[0].bytesperline = pix->width * bpp;
> +	pix->plane_fmt[0].bytesperline = bpl;
>   	pix->plane_fmt[0].sizeimage = pix->plane_fmt[0].bytesperline * pix->height;
>   }
>