I recently installed Ubuntu on my retina Macbook Pro (following this great guide: http://cberner.com/2013/03/01/installing-ubuntu-13-04-on-macbook-pro-retina/) Everything works fine so far however the screen brightness / backlight cannot be adjusted neither by using the assigned key nor by any other means. I know, I'm not the first to address this problem, but all the suggested solutions I found so far did not work for me. I unsuccessfully tried the following: Including Option "RegistryDwords" "EnableBrightnessControl=1" in the Devices-Section of /etc/X11/xorg.conf the application xbacklight I also haven't found any file such as mbp_backlight or apple_backlight on my system which probably would be a starting point I'm using the Nvidia-driver. (BTW: With the nouveau-driver, the keys to adjust the brightness work. However, with the nouveau driver Ubuntu does not resume from suspend mode) Any suggestions what I can do? Thanks!