linux/Documentation/ABI/stable/sysfs-class-backlight
Mauro Carvalho Chehab 98913408c5 docs: ABI: stable: make files ReST compatible
Several entries at the stable ABI files won't parse if we pass
them directly to the ReST output.

Adjust them, in order to allow adding their contents as-is at
the stable ABI book.

Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/467a0dfbcdf00db710a629d3fe4a2563750339d8.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30 13:07:01 +01:00

58 lines
1.9 KiB
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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.