control_brightness=1
# * if your system has the file /proc/acpi/video/vid/lcd/brightness (vid may
# be vid1 or similar), use this file as brightness_output, and use
# the command echo . the possible values can be listed using the
# command:
#
# cat /proc/acpi/video/vid/lcd/brightness
# * if you have a file /sys/class/backlight/.../brightness, then you can use
# that file as brightness_output, and the command echo .
#
# as far as i understand it the values are between 0 and
# the value contained in the file /sys/class/backlight/.../max_brightness.