ac100 team mailing list archive

[Filippi Marco <filippi@xxxxxxxxxxxx>]

Hi,
I wrote a simple init script to save and restore backlight brightness between reboots (have taken urandom as base idea).

If some one wants to try it:
- save the attached script in /etc/init.d and make it executable
- create the wanted sym link in /etc/rc*.d (I suggest rcS.d/S55brightness rc0.d/S30brightness rc6.d/S30brightness)
- create the directory /var/lib/backlight where brightenss value will be saved

all this as root naturally.

My two cents ...

Marco

#! /bin/sh
### BEGIN INIT INFO
# Provides:          brightness
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     S
# Default-Stop:      0 6
# Short-Description: Save and restore brightness between restarts.
# Description:       This script saves the brightness between restarts.
#                    It is called from the boot, halt and reboot scripts.
### END INIT INFO

[ -c /dev/urandom ] || exit 0

PATH=/sbin:/bin
SAVEDFILE=/var/lib/backlight/brightness
. /lib/init/vars.sh

. /lib/lsb/init-functions

do_status () {
	if [ -f $SAVEDFILE ] ; then
		return 0
	else
		return 4
	fi
}

case "$1" in
  start|"")
	[ "$VERBOSE" = no ] || log_action_begin_msg "Restoring backlight brightness"
	cat "$SAVEDFILE" >/sys/class/backlight/pwm-backlight/brightness 2>&1
	ES=$?
	[ "$VERBOSE" = no ] || log_action_end_msg $ES
	;;
  stop)
	# Carry a brightness from shut-down to start-up;
	[ "$VERBOSE" = no ] || log_action_begin_msg "Saving backlight brightness"
	cat /sys/class/backlight/pwm-backlight/brightness > "$SAVEDFILE" 2>&1
	ES=$?
	[ "$VERBOSE" = no ] || log_action_end_msg $ES
	;;
  status)
	do_status
	exit $?
	;;
  restart|reload|force-reload)
	echo "Error: argument '$1' not supported" >&2
	exit 3
	;;
  *)
	echo "Usage: brightness start|stop" >&2
	exit 3
	;;
esac

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