Arch Linux

iduoad

Member

Registered: 2018-01-14

Posts: 17

[SOLVED] Screen brightness is low after startup and refuses to be set

Hi everyone

Lately, after the startup of the system the screen brightness goes to 12 and I can change it using xbacklight.

The screen is bright on the bios and bootloader screen. Also during the system setup. It gets dark when the logind screens shows and after I start my window manager.

I can set the brightness value using xbacklight,nor get its value.

sudo cat /sys/class/backlight/amdgpu_bl1/brightness

gives me 12, even after restart.

I've tried to change the kernel to lts but the issue is still apparent.

This was happening in T14 with AMD GPU.

Last edited by iduoad (2025-01-07 01:21:57)

seth

Member

Registered: 2012-09-03

Posts: 60,805

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

Which kernel?
https://bbs.archlinux.org/viewtopic.php?id=302066

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iduoad

Member

Registered: 2018-01-14

Posts: 17

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

This is happening under: 6.12.7.arch1-1 and linux-lts 6.6.68-1. I will try to downgrade to an older kernel and see what will happen.

Last edited by iduoad (2025-01-02 13:17:39)

seth

Member

Registered: 2012-09-03

Posts: 60,805

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

Can you still control the brightness via the sysfs node?
https://wiki.archlinux.org/title/Backli … interfaces

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

iduoad

Member

Registered: 2018-01-14

Posts: 17

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

Yes I can change it using the sysfs node.

seth

Member

Registered: 2012-09-03

Posts: 60,805

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

https://wiki.archlinux.org/title/Backlight#xbacklight only has ever worked w/ xf86-video-intel, are you using https://archlinux.org/packages/extra/any/acpilight/ and does that indeed also not work?
Do you lack file access permissions?

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

iduoad

Member

Registered: 2018-01-14

Posts: 17

Re: [SOLVED] Screen brightness is low after startup and refuses to be set

The issue is fixed, thank you so much Seth.