first time I've used another distro than ubuntu for a very long time, so that's already saying something ;-). Long time linux user though, started in 1996. It's the btrfs support with the snapshots that won me over (used Arch in the past but found it too buggy - I hope the snapshots can help here). I installed the MATE version.
Anyway, for some reason the brightness keys on my laptop (XPS 13 9370) don't do anything. This has worked always (in any linux live USB stick that I've tried, in ubuntu, etc, hell it even works in the hackintosh install on same laptop ;-)). No idea why. Installed mainline kernel 5.10.1 but same issue. Brightness control works though, screen dims when idle for a while.
Any ideas?
update: these keys don't generate X events (ACPI handled I think), so xev doesn't print anything.
Thanks, but unfortunately no info there. While researching this, everyone that has this issue (apparently a lot) is using some form of Arch linux
Using the /sys interface on the commandline I can control brightness, so it's really the keys that are not working (Fn-up/Fn-down - all other Fn keys work)
Then the other thing I had to do previously (which I thought was the only thing till I accidentally reverted the i915.conf change above) is remove i915 from the MODULES=() block in my /etc/mkinitcpio.conf file and regenerate the boot image (which I had done by reinstalling the linux package to be sure I didn’t accidentally use the wrong syntax calling the utility directly).
I have tried acpi_backlight=vendor, acpi_osi, does not do anything. The options on the i915 driver don’t solve the problem either, and on top they make my system unusably slow.
Just popping by to say how nice it is to see a new forum member who posts details about their issue, researches, and replies with useful information...
Thanks, usually I don't need any help ;-). Professional software dev with 25 years of linux experience ;-). This seems to be an Arch specific issue though, and already going on for a long time, I see people post about this exact problem for years.
Kalhmera.
Although the info on that page is interesting, it mostly addresses the backlight itself not working. It does. I can control it via /sys/class/backlight and via xbacklight. Also it dims by itself when on battery power. The problem is only with the specific backlight keys on the laptop keyboard that don't work. This has worked in all distros that so far (even works in macOS that I have on same laptop ;-)). Only noticed this when I installed garuda.
That’s inspiring. Then start from the start (when Linux boots ).
It seems a hardware issue.
If the HW is not at fault, then the system cannot “hear” the buttons.
Check/install/enable/start acpid and/or AUR search for Dell that shows some relevant, possibly useful packages, (or ideas ).
xev is for Xorg. Check dmesg/journal input in TTY/console (no X). Try to find a Dell oriented keyboard layout (Garuda Settings has a GUI for that, or follow Archwiki guide).
It's not a hardware issue. When I boot with garuda kde lite install usb it works. Same with garuda mate install usb. In installed os it doesn't. Even tried booting from the first snapshot (directly after I installed) and not working. Very strange.
Xev does not see these keypresses. Also in mac os karabiner elements does not see them. Not yet had a chance to check acpid (not on the laptop right now, replying via phone). Will check in an hour or so.
Gave up trying to fix this. Reinstalled from kde lite USB stick I still had laying around. Confirmed keys are working. Tried to upgrade, failed because 'pipewire-support conflicts with pulseaudio-support' neither of which were installed. Reset the KDE settings that were still poluting my home dir, but KDE completely borked. Gave up again. Reinstalled mate. Upgraded and brightness keys are still working. No idea what broke it last time, but solved
It is great that you found a workaround to your issue. However, this may only be temporary as without finding the cause of your problem it may manifest itself again.
I’m not criticizing you for the route you took, but with your level of competancy I was hoping your experience might help contribute to finding a solution to this issue.
I thought a few days back I’d read somewhere that someone had written a service to help correct this Intel issue, but I forgot to save the page where I read it.
Regardless, I’m glad you found a workaround, and again welcome to Garuda.