I haven't had a chance to try these out and I'm not sure how to track these changes through the various repositories and branches but for the record there are some other commits in drm/i915 that are claimed to fix the issue. I'll report back when I get a chance to patch these into 5.3.0-40-generic (which, as a side note, fixes the black screen after resuming from suspend issue on the P1 Gen 2).
fde7266fb2f6 drm/i915: Fix eDP DPCD aux max backlight calculations 79946723092b drm/i915: Assume 100% brightness when not in DPCD control mode 662884a9ad99 drm/i915: Fix DPCD register order in intel_dp_aux_enable_backlight() 9ac7d53d70a2 drm/i915: Auto detect DPCD backlight support by default d2a4bb6f8bc8 drm/i915: Don't use VBT for detecting DPCD backlight controls --- https://gitlab.freedesktop.org/drm/intel/issues/510#note_387666 https://github.com/torvalds/linux/commit/fde7266fb2f6fff2a7fe861474bf198ef0f2449f https://github.com/torvalds/linux/commit/79946723092bde318ff11b3e57a02ba13a30b17e https://github.com/torvalds/linux/commit/662884a9ad992240b8169624aae1b0cc273edc30 https://github.com/torvalds/linux/commit/9ac7d53d70a2b4f43360e3aa0f14a2514339328f https://github.com/torvalds/linux/commit/d2a4bb6f8bc8cf2d788adf7e59b5b52fe3a3333c -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1854413 Title: Backlight adjustments shows OSD but does not change anything on Samsung OLED panel To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1854413/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
