Skip to content

i915: Intel HDR backlight fails to set brightness right after power on after resume from suspend

OLED panel in my Dell XPS 7590 controls brightness through DPCD, however it fails to set brightness after panel power on after resume from suspend.

To reproduce it 2nd time it's enought to do xrandr --output eDP1 --off; xrandr --output eDP1 --auto. It works fine before suspending the machine, so apparently some hardware is not reinitialized properly by driver on resume (or left in unexpected state by BIOS?)

Adding a 100ms into intel_dp_aux_hdr_enable_backlight() fixes the issue.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information