#!/bin/bash
#
# Macbook Air 6,2 power management script 
# copy to /etc/pm/power.d/99macbookair and chmod +x
#

#
# @param $1 idVendor
# @param $2 idProduct
# @param $3 type of powercontrol (on|auto)
#
set_usb_power_control() 
{
	for dev in /sys/bus/usb/devices/* ; do
		if [ -e $dev/idVendor -a \
			 -e $dev/idProduct -a \
			 -e $dev/power/control ] ; then
			if [ x`cat $dev/idVendor` = x$1 -a \
				 x`cat $dev/idProduct` = x$2 ] ; then
				 echo Setting $dev to $3
				 echo $3 > $dev/power/control
			fi
		fi
	done
}

case "$1" in
	true) # powersaving on
		# lower brightness (value from 0 to 2400)
		echo 600 > /sys/class/backlight/intel_backlight/brightness
		# lower keyboard brightness value (value from 0 to 255)
		echo 16 > /sys/class/leds/smc\:\:kbd_backlight/brightness

		# Autosuspend for USB device Apple Internal Keyboard / Trackpad [Apple Inc.]
		# This is not handled by `tlp`
		set_usb_power_control 05ac 0291 auto
		;;
	false) # powersaving off
		;;
	*)
		exit 254
		;;
esac

exit 0