Arch Linux

prohmpossadhorn

Member

Registered: 2021-06-30

Posts: 5

[SLOVED]lenovo Legion 5 15ARH05 cannot change screen brightness

I install Arch linux with uefi on my laptop. I use GNOME.
The display have an output when I set bios to use nvidia gtx 1650 Ti only. When I set bios to switchable Graphic(it have AMD Radeon inside too), the display will not work.
there is no /etc/udev/rules.d/81-backlight.rules presented too.

when I change the brightness using the fn key, the /sys/class/backlight/acpi_video0/brightness change accordingly. But the screen still displays full brightness.
I tried several solutions on the board but nothing gonna work.

I only have folder /sys/class/backlight/acpi_video0/ rater than /ideapad or /nvidia* too.

Can someone know how to fix the issues?

Last edited by prohmpossadhorn (2021-07-06 04:59:36)

prohmpossadhorn

Member

Registered: 2021-06-30

Posts: 5

Re: [SLOVED]lenovo Legion 5 15ARH05 cannot change screen brightness

Finally, I solved the problem. The procedure to set the laptop screen brightness is:
1. change the graphic option from Switchable graphics to Discrete in the UEFI / BIOS
2. creating this file:

sudo nano /usr/share/X11/xorg.conf.d/10-nvidia-brightness.conf

with the following content:

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    Option         "RegistryDwords" "EnableBrightnessControl=1"
EndSection

3. change the grub config in /etc/default/grub by adding the following in GRUB_CMDLINE_LINUX_DEFAULT:

acpi_osi=Linux acpi_backlight=vendor

GRUB_CMDLINE_LINUX_DEFAULT="loglevel=3 quiet splash acpi_osi=Linux acpi_backlight=vendor"

4. generate grub file: sudo grub-mkconfig -o /boot/grub/grub.cfg
5. reboot