#!/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 1 to 15)
        echo 600 > /sys/class/backlight/intel_backlight/brightness
        # lower keyboard brightness value
        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