1What:		/sys/class/backlight/<backlight>/bl_power
2Date:		April 2005
3KernelVersion:	2.6.12
4Contact:	Richard Purdie <rpurdie@rpsys.net>
5Description:
6		Control BACKLIGHT power, values are FB_BLANK_* from fb.h
7		 - FB_BLANK_UNBLANK (0)   : power on.
8		 - FB_BLANK_POWERDOWN (4) : power off
9Users:		HAL
10
11What:		/sys/class/backlight/<backlight>/brightness
12Date:		April 2005
13KernelVersion:	2.6.12
14Contact:	Richard Purdie <rpurdie@rpsys.net>
15Description:
16		Control the brightness for this <backlight>. Values
17		are between 0 and max_brightness. This file will also
18		show the brightness level stored in the driver, which
19		may not be the actual brightness (see actual_brightness).
20Users:		HAL
21
22What:		/sys/class/backlight/<backlight>/actual_brightness
23Date:		March 2006
24KernelVersion:	2.6.17
25Contact:	Richard Purdie <rpurdie@rpsys.net>
26Description:
27		Show the actual brightness by querying the hardware.
28Users:		HAL
29
30What:		/sys/class/backlight/<backlight>/max_brightness
31Date:		April 2005
32KernelVersion:	2.6.12
33Contact:	Richard Purdie <rpurdie@rpsys.net>
34Description:
35		Maximum brightness for <backlight>.
36Users:		HAL
37
38What:		/sys/class/backlight/<backlight>/type
39Date:		September 2010
40KernelVersion:	2.6.37
41Contact:	Matthew Garrett <mjg@redhat.com>
42Description:
43		The type of interface controlled by <backlight>.
44		"firmware": The driver uses a standard firmware interface
45		"platform": The driver uses a platform-specific interface
46		"raw": The driver controls hardware registers directly
47
48		In the general case, when multiple backlight
49		interfaces are available for a single device, firmware
50		control should be preferred to platform control should
51		be preferred to raw control. Using a firmware
52		interface reduces the probability of confusion with
53		the hardware and the OS independently updating the
54		backlight state. Platform interfaces are mostly a
55		holdover from pre-standardisation of firmware
56		interfaces.
57