Add brightness control script

brightness

@@ -0,0 +1,20 @@
+#!/bin/sh
+brightness_dir="/sys/class/backlight/intel_backlight/brightness"
+max_brightness=`cat /sys/class/backlight/intel_backlight/max_brightness`
+current_brightness_level=`cat $brightness_dir`
+new_brightness_level=`expr $current_brightness_level + $1`
+
+if [ "$1" -ge 0 ]; then
+	if [ "$new_brightness_level" -le "$max_brightness" ]; then
+		echo $new_brightness_level > $brightness_dir
+	else
+		echo $max_brightness > $brightness_dir
+	fi
+else
+	if [ "$new_brightness_level" -ge 0 ]; then
+		echo $new_brightness_level > $brightness_dir
+	else
+		echo 0 > $brightness_dir
+	fi
+fi
+