Re: [PATCH] drm/probe-helper: Call drm_mode_validate_ycbcr420() before connector->mode_valid()

[Daniel Vetter <daniel@ffwll.ch>]

On Thu, May 16, 2024 at 08:33:24PM +0300, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Make life easier for drivers by filtering out unwanted YCbCr 4:2:0
> only modes prior to calling the connector->mode_valid() hook.
> Currently drivers will still see YCbCr 4:2:0 only modes in said
> hook, which will likely come as a suprise when the driver has
> declared no support for such modes (via setting
> connector->ycbcr_420_allowed to false).
> 
> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/10992
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Sounds reasonable.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> ---
>  drivers/gpu/drm/drm_probe_helper.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
> index 4f75a1cfd820..249c8c2cb319 100644
> --- a/drivers/gpu/drm/drm_probe_helper.c
> +++ b/drivers/gpu/drm/drm_probe_helper.c
> @@ -474,6 +474,10 @@ static int __drm_helper_update_and_validate(struct drm_connector *connector,
>  		if (mode->status != MODE_OK)
>  			continue;
>  
> +		mode->status = drm_mode_validate_ycbcr420(mode, connector);
> +		if (mode->status != MODE_OK)
> +			continue;
> +
>  		ret = drm_mode_validate_pipeline(mode, connector, ctx,
>  						 &mode->status);
>  		if (ret) {
> @@ -486,10 +490,6 @@ static int __drm_helper_update_and_validate(struct drm_connector *connector,
>  			else
>  				return -EDEADLK;
>  		}
> -
> -		if (mode->status != MODE_OK)
> -			continue;
> -		mode->status = drm_mode_validate_ycbcr420(mode, connector);
>  	}
>  
>  	return 0;
> -- 
> 2.44.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch