I'm running mainline kernel (4.6.3-1) on this machine and I got almost everything working. Now I'm trying to set keyboard shortcuts to change the backlight. It mostly works, but by default the backlight file is read only:
$this->bbcode_second_pass_code('', '$ ls -l /sys/class/backlight/backlight/brightness
-rw-r--r-- 1 root root 4096 jul 12 10:26 /sys/class/backlight/backlight/brightness')
I have tried making this file r/w via tmpfiles.d, but it doesn't work:
$this->bbcode_second_pass_code('', '$ cat /etc/tmpfiles.d/brightness.conf
f /sys/class/backlight/backlight/brightness 0666 - - - 4')
I also tried setting an udev rule to do this without success:
$this->bbcode_second_pass_code('', '$ cat /etc/udev/rules.d/99-backlight.rules
KERNEL="backlight", SUBSYSTEM="backlight", GROUP="users", MODE="0660"')
I'm sure the udev rule must be wrong (will I ever understand udev rules?) but I don't know why using tmpfiles.d does not work... any suggestion is welcome.