Re: [PATCH v11 22/32] rcar-vin: force default colorspace for media centric mode

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Niklas,

Thank you for the patch.

On Friday, 2 March 2018 03:57:41 EET Niklas Söderlund wrote:
> When the VIN driver is running in media centric mode (on Gen3) the
> colorspace is not retrieved from the video source instead the user is
> expected to set it as part of the format. There is no way for the VIN
> driver to validated the colorspace requested by user-space, this creates
> a problem where validation tools fail. Until the user requested
> colorspace can be validated lets force it to the driver default.

The problem here is that the V4L2 specification clearly documents the 
colorspace fields as being set by drivers for capture devices. Using the 
values supplied by userspace thus wouldn't comply with the API. The API has to 
be updated to allow us to implement this feature, but until then Hans wants 
the userspace to be set by the driver to a fixed value. Could you update the 
commit message accordingly, as well as the comment below ?

> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/platform/rcar-vin/rcar-v4l2.c | 16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c
> b/drivers/media/platform/rcar-vin/rcar-v4l2.c index
> 8d92710efffa7276..02f3100ed30db63c 100644
> --- a/drivers/media/platform/rcar-vin/rcar-v4l2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c
> @@ -675,12 +675,24 @@ static const struct v4l2_ioctl_ops rvin_ioctl_ops = {
>   * V4L2 Media Controller
>   */
> 
> +static int rvin_mc_try_format(struct rvin_dev *vin, struct v4l2_pix_format
> *pix) +{
> +	/*
> +	 * There is no way to validate the colorspace provided by the
> +	 * user. Until it can be validated force colorspace to the
> +	 * driver default.
> +	 */
> +	pix->colorspace = RVIN_DEFAULT_COLORSPACE;

Should you also set the xfer_func, quantization and ycbcr_enc ?

Apart from that,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +
> +	return rvin_format_align(vin, pix);
> +}
> +
>  static int rvin_mc_try_fmt_vid_cap(struct file *file, void *priv,
>  				   struct v4l2_format *f)
>  {
>  	struct rvin_dev *vin = video_drvdata(file);
> 
> -	return rvin_format_align(vin, &f->fmt.pix);
> +	return rvin_mc_try_format(vin, &f->fmt.pix);
>  }
> 
>  static int rvin_mc_s_fmt_vid_cap(struct file *file, void *priv,
> @@ -692,7 +704,7 @@ static int rvin_mc_s_fmt_vid_cap(struct file *file, void
> *priv, if (vb2_is_busy(&vin->queue))
>  		return -EBUSY;
> 
> -	ret = rvin_format_align(vin, &f->fmt.pix);
> +	ret = rvin_mc_try_format(vin, &f->fmt.pix);
>  	if (ret)
>  		return ret;


-- 
Regards,

Laurent Pinchart