Created attachment 187974 [details] Logs SUMMARY Powerdevil dims all displays to 30% prior to sleep and randomly fails to restore the dimming setting on secondary monitors when the system wakes. This occurs on around half of wakes. Waiting for the idle timer to trigger a dimming and then cancelling it with an input will restore brightness on all monitors. This is a desktop system with 3 monitors connected, all to the discreet graphics card. The primary monitor is an Alienware AW3423DW, the two secondaries are both Asus VG248QE. The Alienware has HDR enabled, the other two do not. STEPS TO REPRODUCE 1. In System Settings -> Power Management, ensure Dim automatically is on 2. Wait for the system to sleep 3. Wake the system and log in OBSERVED RESULT Around half of the time, secondary monitors will retain a 30% dimming setting. EXPECTED RESULT Dimming value should be restored to 100% across all monitors. SOFTWARE/OS VERSIONS Below is the output of kinfo. Unsure why the 4090 is listed twice, there is only one installed and I'd expect the second graphics processor to be the AMD integrated one. Operating System: Arch Linux KDE Plasma Version: 6.5.4 KDE Frameworks Version: 6.21.0 Qt Version: 6.10.1 Kernel Version: 6.18.2-arch2-1 (64-bit) Graphics Platform: Wayland Processors: 16 × AMD Ryzen 7 9800X3D 8-Core Processor Memory: 64 GiB of RAM (60.4 GiB usable) Graphics Processor 1: NVIDIA GeForce RTX 4090/PCIe/SSE2 Graphics Processor 2: NVIDIA GeForce RTX 4090/PCIe/SSE2 ADDITIONAL INFORMATION This bug has existed since at least plasma version 6.5.2 - the earliest version I tried powerdevil logs & kscreen-doctor output included in attachments
The symptoms seem related to bug 510483 - where the brightness is dimmed to 30% incorrectly It's possible that the brightness is changing by itself because of a crash in powerdevil. I also see traces in the logs you provided. e.g. Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: Traced function stack on entry to i2c_check_open_bus_alive() Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: Traced function stack 0x7fbf54008e40 for current thread [187478] Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: i2c_check_open_bus_alive Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: ddc_write_read_with_retry Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: ddc_get_nontable_vcp_value Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: read_unsupported_feature Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: check_how_unsupported_reported Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: ddc_initial_checks_by_dh Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: ddc_initial_checks_by_dref Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: dw_add_display_by_businfo Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: dw_hotplug_change_handler Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: process_screen_change_event Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: dw_watch_display_connections Can you please run this and see if there are coredumps for powerdevil? sudo coredumpctl --reverse Thanks.
(In reply to TraceyC from comment #1) > The symptoms seem related to bug 510483 - where the brightness is dimmed to > 30% incorrectly > > It's possible that the brightness is changing by itself because of a crash > in powerdevil. I also see traces in the logs you provided. e.g. > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: Traced function stack > on entry to i2c_check_open_bus_alive() > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: Traced function stack > 0x7fbf54008e40 for current thread [187478] > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > i2c_check_open_bus_alive > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > ddc_write_read_with_retry > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > ddc_get_nontable_vcp_value > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > read_unsupported_feature > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > check_how_unsupported_reported > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > ddc_initial_checks_by_dh > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > ddc_initial_checks_by_dref > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > dw_add_display_by_businfo > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > dw_hotplug_change_handler > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > process_screen_change_event > Dec 25 10:46:39 aj-desktop org_kde_powerdevil[1213]: > dw_watch_display_connections > > Can you please run this and see if there are coredumps for powerdevil? > > sudo coredumpctl --reverse > > Thanks. coredumpctl doesn't show any crashes related to powerdevil or anything else around times where the monitor brightness has failed to properly reset. I was able to find that running kscreen-doctor output.DP-4.dimming.100; kscreen-doctor output.DP-5.dimming.100 will restore the brightness without having to wait for the idle timer to dim the screens
Thanks for confirming. Those who are more knowledgeable will have to take it from here.