If you've had Debian on a few boxes you've bound to come cross one with the brightness keys not functioning.
Here are some methods I found to get them working - though the Arch wiki page is much more informative.
sudo nano /etc/default/grub
Change this line
But you may need to specify to the Xorg what device driver to load, e.g Intel.
Create or edit xorg.conf:
add the lines for your devise, e.g. for Intel:
xrandr --output LVDS-1 --brightness 0.8
but I found this fades the screen colours
install xbacklight and run
get error: No outputs have backlight property
sudo setpci -s 00:02.0 F4.B=[value 1-ff]
We can use scripts to bind setpci commands to keys (and here using openbox keybinds)...
add the line
map keys to the scripts - with Openbox this is done in the file lxde-rc.xml or rc.xml in ~/.config/openbox/
then set the new keybindings with: openbox --reconfigure
set the brightness level at start-up with a line in your autostart file...
for LXDE: @sudo setpci -s 00:02.0 F4.B=CC
for Openbox: sudo setpci -s 00:02.0 F4.B=CC
or, make .desktop files in ~/.local/share/applications with the same script commands, name them, set icons and add them to a panel as launchers