On kernel 3.15.1, nothing is in the folder /sys/class/backlight/ so xbacklight does not work.
Since downgrading to kernel 3.14.6, the file /sys/class/backlight/intel_backlight exists so xbacklight works just fine.
Is this happening to anyone else? Do I need to explicitly specify a kernel module now?
Last edited by Vortico (2014-06-23 14:35:34)
I'm having this problem too, also a macbook, model 3,1 with a intel GMA X3100. After suspending with pm-suspend the backlight does also not work (I'm not sure if the screen goes black or the light just turns off).
Looking in dmesg doesn't show anything that I find suspicious, but maybe I'm just not good enough digging.
For now I'm just adding linux to the IgnorePkg line and waiting. Maybe one day I'll try to see if I can find out more.
It is working again in kernel 3.15.5-1.