Subject: Re: [PATCH v13 12/27] drm/i915/dp: Add YCBCR444 handling for sink formats

From: Ville Syrjälä <[email-masked]>
Date: Mon, 13 Apr 2026 22:08:23 +0300

On Mon, Apr 13, 2026 at 12:07:26PM +0200, Nicolas Frattaroli wrote:
> In anticipation of userspace being able to explicitly select supported
> sink formats, add handling of the YCBCR444 sink format. The AUTO path
> does not choose this format, but with explicit format selection added to
> the driver, it becomes a possibility.
> 
> Check for sink support of YCBCR444 to intel_dp_sink_format_valid.
> 
> Signed-off-by: Nicolas Frattaroli <[email-masked]>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 35b8fb5740aa..47bd3d59ea93 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1364,6 +1364,11 @@ intel_dp_sink_format_valid(struct intel_connector *connector,
>  
>  		return MODE_OK;
>  	case INTEL_OUTPUT_FORMAT_RGB:
> +		return MODE_OK;
> +	case INTEL_OUTPUT_FORMAT_YCBCR444:
> +		if (!(info->color_formats & BIT(DRM_OUTPUT_COLOR_FORMAT_YCBCR444)))
> +			return MODE_BAD;

The DP situation is a lot more more fuzzy than the HDMI situation
due to the PCON stuff. So I'm not quite sure what we should do here.

At the very least I think we want the equivalent of
intel_dp_can_ycbcr420() for 444, and the same intel_dp_has_hdmi_sink()
check that we have for 420.

> +
>  		return MODE_OK;
>  	default:
>  		MISSING_CASE(sink_format);
> 
> -- 
> 2.53.0

-- 
Ville Syrjälä
Intel