On Thu, Aug 29, 2013 at 10:58:51AM +0300, Ville Syrjälä wrote:
After that we need to figure out how we can expose them to userspace w/o risking breaking stuff too much. Maybe a new ioctl to enumerate private planes only? And the maybe only accept direct use of private planes via the atomic API, not through the old setplane API. Or if people want to use setplane we could add a flag there indicating that the user is aware of private planes and wants to use them.
FWIW, in my yet to be published new stereo 3D series, I added a DRM_SET_CAP ioctl for userspace to tell DRM to expose some stereo bits in the mode structure.
Making it possible for the primary plane to be exposed as a drm_plane could be the second user of this ioctl (well, assuming people are fine with this new ioctl, a whole different story, but now that'd be 2 users of it).