This patch series creates a new connector property to program colorspace to sink devices. Modern sink devices support more than 1 type of colorspace like 601, 709, BT2020 etc. This helps to switch based on content type which is to be displayed. The decision lies with compositors as to in which scenarios, a particular colorspace will be picked.
This will be helpful mostly to switch to higher gamut colorspaces like BT2020 when the media content is encoded as BT2020. Thereby giving a good visual experience to users.
The expectation from userspace is that it should parse the EDID and get supported colorspaces. Use this property and switch to the one supported. Sink supported colorspaces should be retrieved by userspace from EDID and driver will not explicitly expose them.
Basically the expectation from userspace is: - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink colorspace - Set this new property to let the sink know what it converted the CRTC output to. - This property is just to inform sink what colorspace source is trying to drive.
Have tested this using xrandr by using below command: xrandr --output HDMI2 --set "Colorspace" "BT2020_rgb"
v2: Addressed Ville and Maarten's review comments. Merged the 2nd and 3rd patch into one common logical patch.
v3: Removed Adobe references from enum definitions as per Ville, Hans Verkuil and Jonas Karlman suggestions. Changed default to an unset state where driver will assign the colorspace when not chosen by user, suggested by Ville and Maarten. Addressed other misc review comments from Maarten. Split the changes to have separate colorspace property for DP and HDMI.
v4: Addressed Chris and Ville's review comments, and created a common colorspace property for DP and HDMI, filtered the list
v5: Modified the colorspace property creation helper to take platform specific enum list based on the capabilities of the platform as suggested by Shashank. With this there is no need for segregation between DP and HDMI.
v6: Addressed Shashank's review comments.
v7: Added defines instead of enum in uapi as per Brian Starkey's suggestion in order to go with string matching at userspace. Updated the kernel doc as well with more details.
v8: Addressed Maarten's review comments.
v9: Removed macro defines from uapi as per Brian Starkey and Daniel Stone's comments and moved to drm include file. Moved back to older design with exposing all HDMI colorspaces to userspace since infoframe capability is there even on legacy platforms, as per Ville's review comments.
v10: Addressed Maarten' review comment, updated the RB from Maarten and Jani Nikula's ack. Also fixed sparse warnings and checkpatch complaints.
Uma Shankar (3): drm: Add HDMI colorspace property drm: Add DP colorspace property drm/i915: Attach colorspace property and enable modeset
drivers/gpu/drm/drm_atomic_uapi.c | 4 ++ drivers/gpu/drm/drm_connector.c | 104 +++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_atomic.c | 1 + drivers/gpu/drm/i915/intel_connector.c | 8 +++ drivers/gpu/drm/i915/intel_drv.h | 1 + drivers/gpu/drm/i915/intel_hdmi.c | 25 ++++++++ include/drm/drm_connector.h | 46 +++++++++++++++ 7 files changed, 189 insertions(+)