On Thu, May 31, 2018 at 03:51:37PM +0100, Emil Velikov wrote: > Hi Lowry, > > Small drive-by suggestion. Haven't checked if others have pointed it > out previously :-\ > > On 30 May 2018 at 12:23, Lowry Li <lowry...@arm.com> wrote: > > > +/** > > + * drm_plane_create_blend_mode_property - create a new blend mode property > > + * @plane: drm plane > > + * @supported_modes: bitmask of supported modes, must include > > + * BIT(DRM_MODE_BLEND_PREMULTI) > > + * > There are two possible blend modes (ignoring 'none'), yet premult must > be supported. > What if the hardware can do only "coverage"? > > One-liner explaining why things are as-is would be a great move. > > HTH > Emil Hi Emil,
Thanks for your comments. Yes, we'd add explaining on the comments of the function. About why and regarding supporting more than pre-mult, because the current DRM assumption is that alpha is premultiplied, and old userspace can break if the property defaults to coverage. Please also refer to the discuss record as below on IRC. https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&highlight_names=&date=2018-04-25&show_html=true Please read from around 12:45 to 12:49. :) -- Regards, Lowry _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
