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Diiny

Member

Registered: 2015-05-12

Posts: 21

SOLVED-ish. Latest update to grub stops me from controlling brightness

ASUS TUF Gaming A15 Notebook - 15.6 Inch - 8 GB RAM - 512 GB SSD NVMe - AMD Ryzen 5 7535HS - GF RTX 3050 - A506NC-DS51-CA

$ uname -a
Linux compy 6.14.6-arch1-1 #1 SMP PREEMPT_DYNAMIC Fri, 09 May 2025 17:36:18 +0000 x86_64 GNU/Linux

Up until the grub update today, I was able to change my screen brightness through:

/sys/devices/pci0000:00/0000:00:08.1/0000:05:00.0/drm/card1/card1-eDP-1/amdgpu_bl1/brightness

Today when I logged in, I am getting this error message (which never appeared before the grub update):

tee '/sys/devices/pci0000:00/0000:00:08.1/0000:05:00.0/drm/card1/card1-eDP-1/amdgpu_bl1/brightness': No such file or directory

Doing a search of available brightness controls:

$ sudo find /sys/devices -name brightness
/sys/devices/platform/i8042/serio0/input/input5/input5::capslock/brightness
/sys/devices/platform/i8042/serio0/input/input5/input5::scrolllock/brightness
/sys/devices/platform/i8042/serio0/input/input5/input5::numlock/brightness
/sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/brightness
/sys/devices/pci0000:00/PNP0C14:00/wmi_bus/wmi_bus-PNP0C14:00/603E9613-EF25-4338-A3D0-C46177516DB7/backlight/nvidia_wmi_ec_backlight/brightness
/sys/devices/pci0000:00/0000:00:02.1/0000:02:00.0/net/eno1/enp2s0-0::lan/brightness
/sys/devices/pci0000:00/0000:00:02.1/0000:02:00.0/net/eno1/enp2s0-2::lan/brightness
/sys/devices/pci0000:00/0000:00:02.1/0000:02:00.0/net/eno1/enp2s0-1::lan/brightness

It clearly changed the files.  But using

/sys/devices/pci0000:00/PNP0C14:00/wmi_bus/wmi_bus-PNP0C14:00/603E9613-EF25-4338-A3D0-C46177516DB7/backlight/nvidia_wmi_ec_backlight/brightness

Does not change anything.  How do I get the functionality back?

EDIT:
Ok, when I first setup this laptop, I noticed the "Laptop/ASUS" webpage said to use the following in your grub loader:

acpi_osi=! idle=nomwait acpi_backlight=native

This did nothing for me at the time and I removed it.  I was able to figure out how to control the brightness without it.

After the update to grub today, the option appears to be working as it should.  But I listed this as SOLVED-ish because I noticed strange behavior.  When I change the brightness from the default (whatever it boots to), and I run `xterm`, it puts my screen brightness back to the booting default.  I can't explain it.  If I use a hotkey or I type `xterm` in a terminal, it resets my screens brightness.  I'm assuming I need to make another post.

Last edited by Diiny (2025-05-12 18:52:39)

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,622

Re: SOLVED-ish. Latest update to grub stops me from controlling brightness

Those are kernel parameters, bootloaders do nothing with those except passing them on to the OS .

I'm assuming I need to make another post.

Yes and please make certain grub isn't mentioned in its title .

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky