Xbacklight not working on Plasma KDE

General system Kernel & Hardware
1

Recently, the nvidia drivers got updated, and that broke my brightness controls I believe.

Before, the Increase and Decrease Screen Brightness shortcuts under Settings > Shortcuts > Power Management didn’t work either, and I got around it by setting custom shortcuts that executes the commands light -A 8 and light -U 8 respectively (I think xbacklight wasn’t working then too).

But now, light doesn’t work either now as well, so I believe I want to solve two problems:

  1. How to resolve xbacklight not working? (extra info: just running xbacklight or sudo xbacklight gives no output, I also have xorg-xbacklight installed. I also tried tweaking the kernel parameter acpi_backlight to all of video, native, vendor, and none of them worked)
  2. How to resolve the keyboard shortcut of Increase and Decrease Screen Brightness? This is more minor, but I would like it solved since my current shortcut to brightness is Ctrl+Fn+F5 and Ctrl+Fn+F6, which I think is janky.
2

There were some recent kernel changes in the back end of the brightness APIs which likely broke older programs/utilities.

You may want to check out AUR for brightness and acpilight packages as alternatives.

3

Yeah I’ve tried both of those too, and both didn’t work.

brightness doesn’t do anything when run in command line
I did the setup portion in the acpilight github readme, but still I wasn’t really sure what that was meant to do? There was no acpilight command available even when I restarted my system.

4

Which kernel are you on? uname -a

If on linux, maybe attempt installing linux-lts and rebooting into it to see if you hit a kernel regression.

5

Linux ideapad 6.1.22-1-lts #1 SMP PREEMPT_DYNAMIC Thu, 30 Mar 2023 14:10:04 +0000 x86_64 GNU/Linux