Re: [PATCH v3] media: venus: amend buffer size for bitstream plane

[Hans Verkuil]

On 11/26/2018 11:12 AM, Malathi Gottam wrote:
> Accept the buffer size requested by client and compare it
> against driver calculated size and set the maximum to
> bitstream plane.
> 
> Signed-off-by: Malathi Gottam <mgottam@xxxxxxxxxxxxxx>

Sorry, this isn't allowed. It is the driver that sets the sizeimage value,
never the other way around.

If you need to allocate larger buffers, then use VIDIOC_CREATE_BUFS instead
of VIDIOC_REQBUFS.

What problem are you trying to solve with this patch?

Regards,

	Hans

> ---
>  drivers/media/platform/qcom/venus/venc.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
> index ce85962..e43dd3d 100644
> --- a/drivers/media/platform/qcom/venus/venc.c
> +++ b/drivers/media/platform/qcom/venus/venc.c
> @@ -303,6 +303,7 @@ static int venc_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
>  	struct v4l2_pix_format_mplane *pixmp = &f->fmt.pix_mp;
>  	struct v4l2_plane_pix_format *pfmt = pixmp->plane_fmt;
>  	const struct venus_format *fmt;
> +	u32 sizeimage;
>  
>  	memset(pfmt[0].reserved, 0, sizeof(pfmt[0].reserved));
>  	memset(pixmp->reserved, 0, sizeof(pixmp->reserved));
> @@ -334,9 +335,10 @@ static int venc_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
>  	pixmp->num_planes = fmt->num_planes;
>  	pixmp->flags = 0;
>  
> -	pfmt[0].sizeimage = venus_helper_get_framesz(pixmp->pixelformat,
> -						     pixmp->width,
> -						     pixmp->height);
> +	sizeimage = venus_helper_get_framesz(pixmp->pixelformat,
> +					     pixmp->width,
> +					     pixmp->height);
> +	pfmt[0].sizeimage = max(ALIGN(pfmt[0].sizeimage, SZ_4K), sizeimage);
>  
>  	if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
>  		pfmt[0].bytesperline = ALIGN(pixmp->width, 128);
> @@ -408,8 +410,10 @@ static int venc_s_fmt(struct file *file, void *fh, struct v4l2_format *f)
>  
>  	if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
>  		inst->fmt_out = fmt;
> -	else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
> +	else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
>  		inst->fmt_cap = fmt;
> +		inst->output_buf_size = pixmp->plane_fmt[0].sizeimage;
> +	}
>  
>  	return 0;
>  }
> @@ -908,6 +912,7 @@ static int venc_queue_setup(struct vb2_queue *q,
>  		sizes[0] = venus_helper_get_framesz(inst->fmt_cap->pixfmt,
>  						    inst->width,
>  						    inst->height);
> +		sizes[0] = max(sizes[0], inst->output_buf_size);
>  		inst->output_buf_size = sizes[0];
>  		break;
>  	default:
>