[PATCH 0/4] drm/dp,i915: eDP DPCD backlight control detection fixes

Lyude Paul lyude at redhat.com
Tue Feb 4 19:28:08 UTC 2020


Unfortunately, it turned out that the DPCD is also not a reliable way of
probing for DPCD backlight support as some panels will lie and say they
have DPCD backlight controls when they don't actually.

So, revert back to the old behavior and add a bunch of EDID-based DP
quirks for the panels that we know need this. As you might have already
guessed, OUI quirks didn't seem to be a very safe bet for these panels
due to them not having their device IDs filled out.

Lyude Paul (4):
  Revert "drm/i915: Don't use VBT for detecting DPCD backlight controls"
  drm/dp: Introduce EDID-based quirks
  drm/i915: Force DPCD backlight mode on X1 Extreme 2nd Gen 4K AMOLED
    panel
  drm/i915: Force DPCD backlight mode for some Precision 7750 panels

 drivers/gpu/drm/drm_dp_helper.c               | 78 +++++++++++++++++++
 drivers/gpu/drm/drm_dp_mst_topology.c         |  3 +-
 .../drm/i915/display/intel_display_types.h    |  1 +
 drivers/gpu/drm/i915/display/intel_dp.c       | 11 ++-
 .../drm/i915/display/intel_dp_aux_backlight.c | 28 +++++--
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  2 +-
 drivers/gpu/drm/i915/display/intel_psr.c      |  2 +-
 include/drm/drm_dp_helper.h                   | 21 ++++-
 8 files changed, 130 insertions(+), 16 deletions(-)

-- 
2.24.1



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