Apple Backlight Driver

modulename: apple_bl.ko

configname: CONFIG_BACKLIGHT_APPLE

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>Backlight & LCD device support
└─>Apple Backlight Driver
In linux kernel since version 2.6.39 (release Date: 2011-05-18)  
If you have an Intel-based Apple say Y to enable a driver for its
backlight.

source code:
drivers/video/backlight/apple_bl.c