Use libbacklight to export BACKLIGHT through XRandR
@hadess
Submitted by Bastien Nocera Assigned to Xorg Project Team
Description
libbacklight itself: http://cgit.freedesktop.org/libbacklight/
The DDX should use this to ensure that the GPU driving the display is the one that gets the associated backlight changed as necessary.
This would fix problems on machines with multiple GPUs, whether all used at the same time, or one at a time.