Re: [gentoo-user] How to dim the display brightness

[Steffen Loos <fenlo@gmx.net>]

Hello Damian,

>>> and take a look if /sys/class/backlight/acpi_video0/ is present:
On an IBM T61 i have acpi_video1 too. Video0 represents the vga/dvi output where video1 represents the LCD.
Also have a look on max_brightness on this dirs for the maximum value. 

>>
>>> You can use xev to see which keycode is emmitted and then look in your
>>> desktop environment if this is match with some action.
>> In fact, Fn + dimming keys produces output. Now, to do something
>> useful, I need to know how to dim the light of the LCD.
As workarround you could switch to a console (Ctrl+Alt+F1) and try to dim with your fn+ keys.

>>
>>> Well. it should be somehow applicable, because it is rather generic.
>> I don't know how to replace this line
>>    echo "level ${LEVEL}" > /proc/acpi/ibm/brightness
>>
>> I have a file
>>    /proc/acpi/video/C14B/C160/brightness
>> whose contents look like
>>    levels:  100 51 30 37 44 51 58 65 72 79 86 93 100
>>    current: 72
Be careful to touch the right (video-)output. In /proc/acpi/video i have two devices: VID and VID1. VID1 references to my LCD.

Steffen