57 lines
1.9 KiB
Plaintext
57 lines
1.9 KiB
Plaintext
|
What: /sys/class/backlight/<backlight>/bl_power
|
||
|
|
Date: April 2005
|
||
|
|
KernelVersion: 2.6.12
|
||
|
|
Contact: Richard Purdie <rpurdie@rpsys.net>
|
||
|
|
Description:
|
||
|
|
Control BACKLIGHT power, values are FB_BLANK_* from fb.h
|
||
|
|
- FB_BLANK_UNBLANK (0) : power on.
|
||
|
|
- FB_BLANK_POWERDOWN (4) : power off
|
||
|
|
Users: HAL
|
||
|
|
|
||
|
|
What: /sys/class/backlight/<backlight>/brightness
|
||
|
|
Date: April 2005
|
||
|
|
KernelVersion: 2.6.12
|
||
|
|
Contact: Richard Purdie <rpurdie@rpsys.net>
|
||
|
|
Description:
|
||
|
|
Control the brightness for this <backlight>. Values
|
||
|
|
are between 0 and max_brightness. This file will also
|
||
|
|
show the brightness level stored in the driver, which
|
||
|
|
may not be the actual brightness (see actual_brightness).
|
||
|
|
Users: HAL
|
||
|
|
|
||
|
|
What: /sys/class/backlight/<backlight>/actual_brightness
|
||
|
|
Date: March 2006
|
||
|
|
KernelVersion: 2.6.17
|
||
|
|
Contact: Richard Purdie <rpurdie@rpsys.net>
|
||
|
|
Description:
|
||
|
|
Show the actual brightness by querying the hardware.
|
||
|
|
Users: HAL
|
||
|
|
|
||
|
|
What: /sys/class/backlight/<backlight>/max_brightness
|
||
|
|
Date: April 2005
|
||
|
|
KernelVersion: 2.6.12
|
||
|
|
Contact: Richard Purdie <rpurdie@rpsys.net>
|
||
|
|
Description:
|
||
|
|
Maximum brightness for <backlight>.
|
||
|
|
Users: HAL
|
||
|
|
|
||
|
|
What: /sys/class/backlight/<backlight>/type
|
||
|
|
Date: September 2010
|
||
|
|
KernelVersion: 2.6.37
|
||
|
|
Contact: Matthew Garrett <mjg@redhat.com>
|
||
|
|
Description:
|
||
|
|
The type of interface controlled by <backlight>.
|
||
|
|
"firmware": The driver uses a standard firmware interface
|
||
|
|
"platform": The driver uses a platform-specific interface
|
||
|
|
"raw": The driver controls hardware registers directly
|
||
|
|
|
||
|
|
In the general case, when multiple backlight
|
||
|
|
interfaces are available for a single device, firmware
|
||
|
|
control should be preferred to platform control should
|
||
|
|
be preferred to raw control. Using a firmware
|
||
|
|
interface reduces the probability of confusion with
|
||
|
|
the hardware and the OS independently updating the
|
||
|
|
backlight state. Platform interfaces are mostly a
|
||
|
|
holdover from pre-standardisation of firmware
|
||
|
|
interfaces.
|