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+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)
+ - power-supply: regulator for supply voltage
+
+Optional properties:
+ - pwm-names: a list of names for the PWM devices specified in the
+ "pwms" property (see PWM binding[0])
+ - enable-gpios: contains a single GPIO specifier for the GPIO which enables
+ and disables the backlight (see GPIO binding[1])
+
+[0]: Documentation/devicetree/bindings/pwm/pwm.txt
+[1]: Documentation/devicetree/bindings/gpio/gpio.txt
+
+Example:
+
+ backlight {
+ compatible = "pwm-backlight";
+ pwms = <&pwm 0 5000000>;
+
+ brightness-levels = <0 4 8 16 32 64 128 255>;
+ default-brightness-level = <6>;
+
+ power-supply = <&vdd_bl_reg>;
+ enable-gpios = <&gpio 58 0>;
+ };