Lenovo Thinkpad X1 Extreme Gen 3 Unable to Adjust Backlight after Upgrading to Linux 5.10

[farzadm]

Hello everyone,

Today I saw a message suggesting to update to 5.10 kernel, and I happily did it, but now I cannot adjust my laptop’s screen backlight.

On Linux 5.9, I adjust the backlight by writing to the file /sys/class/backlight/nvidia_0/brightness, and if I look at the nvidia_0 directory, it’s a symlink to another directory:

lrwxrwxrwx root root 0 B 5 minutes ago nvidia_0 ⇒ ../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/backlight/nvidia_0

But when I boot using 5.10, my /sys/class/backlight directory is empty.

On Linux 5.9, I have the following when I search for backlight in /sys/devices:

pci0000:00/0000:00:01.0/0000:01:00.0/backlight
platform/thinkpad_acpi/leds/tpacpi::kbd_backlight

But on Linux 5.10, I only have this:

platform/thinkpad_acpi/leds/tpacpi::kbd_backlight

I get this when I do mhwd -li:

Warning: config '/var/lib/mhwd/local/pci/video-nvidia-455xx/MHWDCONFIG' is invalid!
> Installed PCI configs:
--------------------------------------------------------------------------------
                  NAME               VERSION          FREEDRIVER           TYPE
--------------------------------------------------------------------------------
          video-nvidia            2020.11.30               false            PCI


Warning: No installed USB configs!

I’m not sure what the warning is about, but on 5.9, I also get the warning, and the backlight works

[TriMoon]

@farzadm

I’m not sure what the warning is about, but on 5.9, I also get the warning

That means there is something wrong with your driver install, it might be related…
Try to fully uninstall the driver using mhwd and then re-install it.

PS: I added the #kernel tag so it will be better spotted by people watching that tag only…

[farzadm]

@TriMoon

Try to fully uninstall the driver using mhwd and then re-install it

Thank you @TriMoon, I’ll give that a shot

@TriMoon

PS: I added the #kernel tag so it will be better spotted by people watching that tag only…

thank you

[farzadm]

@TriMoon

Try to fully uninstall the driver using mhwd and then re-install it.

I tried that, and it didn’t work

I guess nobody knows how to solve this problem

[TriMoon]

Give it time, maybe in near future someone with enough knowledge will notice this topic
We can know a lot,but not everything, and no-one is online on the forum 24/7 that knows how to solve every problem

[farzadm]

Totally agree @TriMoon, but from past experience, if I don’t get an answer in the first 1 or 2 days, I won’t get it ever!

I really hope what you said happens because it’s basically blocking me from going to 5.10

[TriMoon]

I just remembered a topic relating to backlight that you might want to check out:

Xrandr increase brightness in incraments

Hi, I recently installed manjaro with awesome wm, and it has worked great, apart from the brightness and volume keys. I did a lazy fix for the volume keys by adding a custom key shortcut to my rc.lua: awful.key({ modkey }, "=" function () awful.util.spawn("amixer -q sset Master 5%+") end, {description = "volume up (%5)", group = "volume"} This works for volume, but i wanted to do the same for Brghtness, i found that i can adjust brightness with xrandr --brigh…

[janlugt]

I have the same issue on a Dell XPS 15 with OLED screen. Brightness is adjustable on 5.9 (I believe because of some patches that were cherrypicked in the Manjaro kernel), but it broke in 5.10.

[pobrn]

@janlugt there are new patches available as of 2020-12-04. @schinfo @philm maybe you could incorporate those into the Manjaro kernel builds if you deem them appropriate?

[schinfo]

The patches doesn’t work - build is broken if they are included.

[phush0]

They will be included by default in 5.12, till then use icc-brightness-gnome-git