Arch Linux

-MacNuke-

Member

Registered: 2013-01-29

Posts: 24

[SOLVED] Backlight control only over radeon_bl0?

Hi,

I installed ArchLinux on my iMac 12.1 today and everything seems to work like a charm. I am using the OpenSource radeon-driver which work well (Radeon HD 6770M).

The Fn-Keys setting the backlight via

/sys/class/backlight/acpi_video0/brightness

but this does not work. The thing is that I can change the backlight via

echo 10 > /sys/class/backlight/radeon_bl0/brightness

and this works.

What can I do now, to get the Fn-Keys working? Can I change the behaviour of the Fn-Keys or can I fix the acpi_video0 part?

edit:

Haha, right after the post I found the solution... xD

I added "acpi_backlight=vendor" to my kernel boot parameters....

Last edited by -MacNuke- (2013-03-14 21:32:40)

Grit

Member

Registered: 2015-08-01

Posts: 1

Re: [SOLVED] Backlight control only over radeon_bl0?

HI,

don't know how to thank you enough. Now I can dim my screen so low that even smartphones can't do.

I tried echo 1 > and, even in the darkest environment, it's so dimmed that it barely emitted the light and barely was able to be seen, lol.

AnAkkk

Member

Registered: 2014-03-03

Posts: 148

Re: [SOLVED] Backlight control only over radeon_bl0?

If it doesn't work out of the box, then you should fill in a kernel bug report. Workarounds like acpi_backlight=vendor are not normally meant to be used.

WorMzy

Forum Moderator

From: Scotland

Registered: 2010-06-16

Posts: 11,844

Website

Re: [SOLVED] Backlight control only over radeon_bl0?

Grit, welcome to the Arch Linux forums. Please take a moment to read through the forum etiquette; particularly the section regarding old threads and necrobumping.

Closing.

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Sakura:-
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