Arch Linux

ivancerovina

Member

Registered: 2024-09-10

Posts: 2

Backlight not working (ASUS laptop)

Hey, I'm dual booting Windows 11 and Arch Linux and I'm having issues with backlight controls. It's dimmed (usable) and unchangeable.

Specifications:
Laptop: Asus TUF A15
Processor: Ryzen 5 7535HS
Graphics: NVIDIA RTX 3050 Mobile
OS: Arch Linux x86_64
Kernel: 6.10.8-arch1-2.1-g14
DE: Plasma 6.1.4
WM: kwin

These NVIDIA packages (drivers) have been installed:

nvidia-dkms nvidia-utils lib32-nvidia-utils

So far I've tried installing a few backlight packages from the wiki (acpilight, backlight_control and brightnessctl).
I've also tried directly changing the brightness in

/sys/class/backlight/nvidia_wmi_ec_backlight

This is my systemd boot configuration

title        Linux Arch (G14)
linux        /vmlinuz-linux-g14
initrd       /initramfs-linux-g14.img
options      root=UUID=15d6af8a-79be-4750-8a7e-5485e99cb236 nvidia-drm.modeset=1 acpi_backlight=nvidia_wmi_ec rw

When I run journalctl -f and use my keyboard backlight controls, I get this error:

Sep 10 17:01:08 ivan-arch plasmashell[1468]: The cached device pixel ratio value was stale on window update.  Please file a QTBUG which explains how to reproduce.
Sep 10 17:01:08 ivan-arch kernel: ACPI BIOS Error (bug): Could not resolve symbol [^PCI0.GPP0.PEGP.EDP1], AE_NOT_FOUND (20240322/psargs-330)
Sep 10 17:01:08 ivan-arch kernel: ACPI Error: Aborting method \_SB.BRTN due to previous error (AE_NOT_FOUND) (20240322/psparse-529)
Sep 10 17:01:08 ivan-arch kernel: ACPI Error: Aborting method \_SB.PCI0.SBRG.EC0.QLIB due to previous error (AE_NOT_FOUND) (20240322/psparse-529)
Sep 10 17:01:08 ivan-arch kernel: ACPI Error: Aborting method \_SB.PCI0.SBRG.EC0._Q17 due to previous error (AE_NOT_FOUND) (20240322/psparse-529)

As I'm pretty new to Arch, I'm providing you with all information that I can think of (I have no idea if it's relevant), and help would be greatly appreciated. Thank you!

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,208

Re: Backlight not working (ASUS laptop)

How sure are you the screen is attached to the nvidia and not the amd card? if you get rid of the acpi_backlight parameter do you still have the issue?

ivancerovina

Member

Registered: 2024-09-10

Posts: 2

Re: Backlight not working (ASUS laptop)

When I remove that parameter, the only directory in

/sys/class/backlight

is still

nvidia_wmi_ec_backlight

I've also tried:

acpi_backlight=video
acpi_backlight=vendor
acpi_backlight=native