How to enable control keyboard backlight in xmonad?

I'm using xmonad -tiling window manager- and lux to control backlight but keyboard backlight via fn doesn't work. Does anyone know a solution?

Thanks for help.


One solution is to run xmonad on top of a desktop environment such as Mate or Gnome-Flashback. This makes things much peaceful since the DE takes care of managing systrays / functions keys / disk mounts / authentication and other small things that might take a long time figuring out on a pure xmonad setup