[PATCH 02/13] drm/connector: Add helper to check if a mode requires scrambling

[Ville Syrjälä]

On Tue, Nov 02, 2021 at 03:59:33PM +0100, Maxime Ripard wrote:
> --- a/include/drm/drm_modes.h
> +++ b/include/drm/drm_modes.h
> @@ -424,6 +424,21 @@ static inline bool drm_mode_is_stereo(const struct drm_display_mode *mode)
>  	return mode->flags & DRM_MODE_FLAG_3D_MASK;
>  }
>  
> +/**
> + * drm_mode_hdmi_requires_scrambling - Checks if a mode requires HDMI Scrambling
> + * @mode: DRM display mode
> + *
> + * Checks if a given display mode requires the scrambling to be enabled.
> + *
> + * Returns:
> + * A boolean stating whether it's required or not.
> + */
> +static inline bool
> +drm_mode_hdmi_requires_scrambling(const struct drm_display_mode *mode)
> +{
> +	return mode->clock > DRM_HDMI_14_MAX_TMDS_CLK_KHZ;
> +}

That's only correct for 8bpc. The actual limit is on the TMDS clock (or
rather TMDS character rate as HDMI 2.0 calls it due to the 1/1 vs. 1/4
magic for the actually transmitted TMDS clock).

-- 
Ville Syrjälä
Intel