On Thu, Jun 22, 2017 at 10:33 AM, Sharma, Shashank shashank.sharma@intel.com wrote:
- The property values should be limited to what the driver can support, I guess that would mean limiting the available ycbcr modes? Or does all our hw support all the modes, including 420 (on the sink side)?
This property is targeted at DRM layer, so naturally its for all the HWs along with Intel HW, so it serves a big range. All our HDMI 1.4 sources support RGB444, and after this series, can support YCBCR444. All HDMI 2.0 sources should support YCBCR420, but they can declare this using a bool variable which I added in patch 3 (ycbcr420_allowed) As we are targeting both HDMI 1.4 as well as HDMI 2.0 (Src and Sink), as a whole we are covering all options.
Yes, we need to define values for everything, since it's a generic property. But for a given driver imo we should only allow the values that are actually supported. An example would be the rotation property, which supporsts X/Y-mirror and rotation by 90° steps. But on a given i915 platform we only register support for the stuff the driver/hw can do, e.g. pre-gen9 do not register 90/270° rotation. I think we should do the same here. See drm_plane_create_rotation_property(), specifically the supported_rotations parameter.
Cheers, Daniel