[Intel-gfx] [PATCH] drm/i915: remove pixel doubled HDMI modes from valid modes list

[Chris Wilson]

On Mon, Aug 11, 2014 at 03:33:02PM -0700, clinton.a.taylor at intel.com wrote:
> From: Clint Taylor <clinton.a.taylor at intel.com>
> 
> Intel HDMI does not correctly configure pixel replicated HDMI modes
> 480i and 576i. Remove support for these modes until DRM has been
> changed to correctly identify SD interlaced modes by reporting there
> true horizontal resolution 720 instead of the pre-pixel doubled 1440.
> 
> Signed-off-by: Clint Taylor <clinton.a.taylor at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_hdmi.c |    3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
> index 5f47d35..ab32523 100644
> --- a/drivers/gpu/drm/i915/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
> @@ -873,6 +873,9 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
>  	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
>  		return MODE_NO_DBLESCAN;
>  

If it is just a workaround for a drm bug. You need a big comment
explaining why you w/a rather than pressing for the bug fix.

> +	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
> +		return MODE_NO_INTERLACE;
> +

-- 
Chris Wilson, Intel Open Source Technology Centre