forked from analogdevicesinc/linux
-
Notifications
You must be signed in to change notification settings - Fork 3
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
pwm-backlight: Add rudimentary device tree support
This commit adds very basic support for device tree probing. Currently, only a PWM and a list of distinct brightness levels can be specified. Enabling or disabling backlight power via GPIOs is not yet supported. Reviewed-by: Shawn Guo <[email protected]> Reviewed-by: Mark Brown <[email protected]> Signed-off-by: Thierry Reding <[email protected]>
- Loading branch information
Thierry Reding
committed
Jul 23, 2012
1 parent
4dce82c
commit 3e3ed6c
Showing
4 changed files
with
159 additions
and
21 deletions.
There are no files selected for viewing
28 changes: 28 additions & 0 deletions
28
Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,28 @@ | ||
pwm-backlight bindings | ||
|
||
Required properties: | ||
- compatible: "pwm-backlight" | ||
- pwms: OF device-tree PWM specification (see PWM binding[0]) | ||
- brightness-levels: Array of distinct brightness levels. Typically these | ||
are in the range from 0 to 255, but any range starting at 0 will do. | ||
The actual brightness level (PWM duty cycle) will be interpolated | ||
from these values. 0 means a 0% duty cycle (darkest/off), while the | ||
last value in the array represents a 100% duty cycle (brightest). | ||
- default-brightness-level: the default brightness level (index into the | ||
array defined by the "brightness-levels" property) | ||
|
||
Optional properties: | ||
- pwm-names: a list of names for the PWM devices specified in the | ||
"pwms" property (see PWM binding[0]) | ||
|
||
[0]: Documentation/devicetree/bindings/pwm/pwm.txt | ||
|
||
Example: | ||
|
||
backlight { | ||
compatible = "pwm-backlight"; | ||
pwms = <&pwm 0 5000000>; | ||
|
||
brightness-levels = <0 4 8 16 32 64 128 255>; | ||
default-brightness-level = <6>; | ||
}; |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters