Fader is combination of faderd daemon with fader command line utility for backlight control in linux. It still needs some touch and polishing but I already use it daily. I will be glad if it works for you as well.

faderd [-d PATH]

• -d PATH sets the path to the backlight control directory. It is set to /sys/class/backlight/intel_backlight by default (my default).

This server runs forever, waits for commands in /tmp/fader.sock and changes brightness appropriately.

fader [+|-]NUMBER[%]

This is user utility for sending commands to the faderd through /tmp/fader.sock. It accepts exactly one parameter with decimal NUMBER which may be prefixed with + or - and suffixed with %. The usage should be intuitive, but here is few examples for clarification:

• fader 10 - set the brightness to 10
• fader 10% - set the brightness to 10%
• fader +10 - increase brightness by 10
• fader -10% - decrease brightness by 10%

Run make in source directory in order to compile fader and faderd programs.