A while ago we ran into issues while trying to enable the eDP backlight control interface as defined by VESA, in order to make the DPCD backlight controls on newer laptop panels work. The issue ended up being much more complicated however, as we also apparently needed to add support for an Intel-specific DPCD backlight control interface as the VESA interface is broken on many laptop panels. For lack of a better name, we just call this the Intel HDR backlight interface.
While this only adds support for the SDR backlight mode (I think), this will fix a lot of user's laptop panels that we weren't able to properly automatically detect DPCD backlight controls on previously.
Series-wide changes in v3: * Pass down brightness values to enable/disable backlight callbacks in a separate patch * Rebase
Lyude Paul (4): drm/i915: Keep track of pwm-related backlight hooks separately drm/i915/dp: Enable Intel's HDR backlight interface (only SDR for now) drm/i915/dp: Allow forcing specific interfaces through enable_dpcd_backlight drm/dp: Revert "drm/dp: Introduce EDID-based quirks"
drivers/gpu/drm/drm_dp_helper.c | 83 +--- drivers/gpu/drm/drm_dp_mst_topology.c | 3 +- .../drm/i915/display/intel_display_types.h | 14 +- drivers/gpu/drm/i915/display/intel_dp.c | 9 +- .../drm/i915/display/intel_dp_aux_backlight.c | 286 ++++++++++++-- drivers/gpu/drm/i915/display/intel_dp_mst.c | 3 +- drivers/gpu/drm/i915/display/intel_panel.c | 368 +++++++++++------- drivers/gpu/drm/i915/display/intel_panel.h | 4 + drivers/gpu/drm/i915/display/intel_psr.c | 2 +- drivers/gpu/drm/i915/i915_params.c | 2 +- include/drm/drm_dp_helper.h | 21 +- 11 files changed, 504 insertions(+), 291 deletions(-)