CONTROL_BRIGHTNESS=1 BATT_BRIGHTNESS_COMMAND="echo 13" LM_AC_BRIGHTNESS_COMMAND="echo 13" NOLM_AC_BRIGHTNESS_COMMAND="echo 13" BRIGHTNESS_OUTPUT="/sys/class/backlight/acpi_video0/brightness"
安装laptop-mode-tools
所有设置请man laptop-mode.conf.
查看这个文件：/etc/laptop-mode/conf.d/lcd-brightness.conf
原文：http://www.cnblogs.com/flymeng/p/7900670.html