Arch Linux

turion

Member

Registered: 2011-12-13

Posts: 10

LCD brightness inverted (radeon driver)

Hello there!
I have a HP Compaq nx6325 with the radeon video driver from the package ati-dri.

When I execute

echo -n 1 > /sys/class/backlight/acpi_video0/brightness

, the brightness of my builtin LCD goes down to the minimum as expected.

When I execute

echo -n 1 > /sys/class/backlight/radeon_bl/brightness

, the brightness does not go down to the minimum, but to the maximum. So somehow the radeon driver inverts the brightness of the LCD screen?

This in itself would not be to bad if the laptop keys for setting the brightness wouldn't do the following strange thing:
If I press the "brightness up"-key in an x-session, first the brightness value in acpi_video0 is changed, and maybe the tenth of a second later, the brightness value in radeon_bl is changed. So the brightness flashes up for a moment and goes all the way down again, which is very anoying.
When I do the same thing in the console outside x, the radeon_bl value is untouched and everything behaves normal.

How can I change that annoying inverted behaviour?