Re: [PATCH] media: cedrus: Propagate OUTPUT resolution to CAPTURE

[Nicolas Dufresne <nicolas.dufresne@collabora.com>]

Le jeudi 14 mai 2020 à 11:39 -0400, Nicolas Dufresne a écrit :
> As per spec, the CAPTURE resolution should be automatically set based on
> the OTUPUT resolution. This patch properly propagate width/height to the
> capture when the OUTPUT format is set and override the user provided
> width/height with configured OUTPUT resolution when the CAPTURE fmt is
> updated.
> 
> This also prevents userspace from selecting a CAPTURE resolution that is
> too small, avoiding unwanted page faults.

Side note, this patch is based on top of "Samuel Holland <samuel@sholland.org>"
patches:

	[PATCH v3 1/2] media: cedrus: Program output format during each run
	[PATCH v3 2/2] media: cedrus: Implement runtime PM

As the patchset also fixes concurrent decoding issues. This was tested using
GStreamer implementation, which strictly follow the Stateless CODEC spec and
expect OUTPUT to CAPTURE width/height propagation.

> 
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> ---
>  drivers/staging/media/sunxi/cedrus/cedrus_video.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> index 16d82309e7b6..a6d6b15adc2e 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
> @@ -247,6 +247,8 @@ static int cedrus_try_fmt_vid_cap(struct file *file, void
> *priv,
>  		return -EINVAL;
>  
>  	pix_fmt->pixelformat = fmt->pixelformat;
> +	pix_fmt->width = ctx->src_fmt.width;
> +	pix_fmt->height = ctx->src_fmt.height;
>  	cedrus_prepare_format(pix_fmt);
>  
>  	return 0;
> @@ -319,11 +321,14 @@ static int cedrus_s_fmt_vid_out(struct file *file, void
> *priv,
>  		break;
>  	}
>  
> -	/* Propagate colorspace information to capture. */
> +	/* Propagate format information to capture. */
>  	ctx->dst_fmt.colorspace = f->fmt.pix.colorspace;
>  	ctx->dst_fmt.xfer_func = f->fmt.pix.xfer_func;
>  	ctx->dst_fmt.ycbcr_enc = f->fmt.pix.ycbcr_enc;
>  	ctx->dst_fmt.quantization = f->fmt.pix.quantization;
> +	ctx->dst_fmt.width = ctx->src_fmt.width;
> +	ctx->dst_fmt.height = ctx->src_fmt.height;
> +	cedrus_prepare_format(&ctx->dst_fmt);
>  
>  	return 0;
>  }