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[linux/fpc-iii.git] / Documentation / devicetree / bindings / video / backlight / pwm-backlight.txt
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1 pwm-backlight bindings
3 Required properties:
4   - compatible: "pwm-backlight"
5   - pwms: OF device-tree PWM specification (see PWM binding[0])
6   - brightness-levels: Array of distinct brightness levels. Typically these
7       are in the range from 0 to 255, but any range starting at 0 will do.
8       The actual brightness level (PWM duty cycle) will be interpolated
9       from these values. 0 means a 0% duty cycle (darkest/off), while the
10       last value in the array represents a 100% duty cycle (brightest).
11   - default-brightness-level: the default brightness level (index into the
12       array defined by the "brightness-levels" property)
13   - power-supply: regulator for supply voltage
15 Optional properties:
16   - pwm-names: a list of names for the PWM devices specified in the
17                "pwms" property (see PWM binding[0])
18   - enable-gpios: contains a single GPIO specifier for the GPIO which enables
19                   and disables the backlight (see GPIO binding[1])
21 [0]: Documentation/devicetree/bindings/pwm/pwm.txt
22 [1]: Documentation/devicetree/bindings/gpio/gpio.txt
24 Example:
26         backlight {
27                 compatible = "pwm-backlight";
28                 pwms = <&pwm 0 5000000>;
30                 brightness-levels = <0 4 8 16 32 64 128 255>;
31                 default-brightness-level = <6>;
33                 power-supply = <&vdd_bl_reg>;
34                 enable-gpios = <&gpio 58 0>;
35         };