diff options
Diffstat (limited to 'Documentation/devicetree/bindings/leds')
4 files changed, 64 insertions, 9 deletions
diff --git a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt index 310810906613..64fa2fbd98c9 100644 --- a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt +++ b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt @@ -3,13 +3,6 @@ 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: @@ -21,6 +14,19 @@ Optional properties: and enabling the backlight using GPIO. - pwm-off-delay-ms: Delay in ms between disabling the backlight using GPIO and setting PWM value to 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). + - num-interpolated-steps: Number of interpolated steps between each value + of brightness-levels table. This way a high + resolution pwm duty cycle can be used without + having to list out every possible value in the + brightness-level array. [0]: Documentation/devicetree/bindings/pwm/pwm.txt [1]: Documentation/devicetree/bindings/gpio/gpio.txt @@ -39,3 +45,17 @@ Example: post-pwm-on-delay-ms = <10>; pwm-off-delay-ms = <10>; }; + +Example using num-interpolation-steps: + + backlight { + compatible = "pwm-backlight"; + pwms = <&pwm 0 5000000>; + + brightness-levels = <0 2048 4096 8192 16384 65535>; + num-interpolated-steps = <2048>; + default-brightness-level = <4096>; + + power-supply = <&vdd_bl_reg>; + enable-gpios = <&gpio 58 0>; + }; diff --git a/Documentation/devicetree/bindings/leds/common.txt b/Documentation/devicetree/bindings/leds/common.txt index 1d4afe9644b6..aa1399814a2a 100644 --- a/Documentation/devicetree/bindings/leds/common.txt +++ b/Documentation/devicetree/bindings/leds/common.txt @@ -31,7 +31,7 @@ Optional properties for child nodes: "backlight" - LED will act as a back-light, controlled by the framebuffer system "default-on" - LED will turn on (but for leds-gpio see "default-state" - property in Documentation/devicetree/bindings/gpio/led.txt) + property in Documentation/devicetree/bindings/leds/leds-gpio.txt) "heartbeat" - LED "double" flashes at a load average based rate "disk-activity" - LED indicates disk activity "ide-disk" - LED indicates IDE disk activity (deprecated), diff --git a/Documentation/devicetree/bindings/leds/leds-lm3692x.txt b/Documentation/devicetree/bindings/leds/leds-lm3692x.txt index 6c9074f84a51..08b352840bd7 100644 --- a/Documentation/devicetree/bindings/leds/leds-lm3692x.txt +++ b/Documentation/devicetree/bindings/leds/leds-lm3692x.txt @@ -20,7 +20,10 @@ Optional properties: - vled-supply : LED supply Required child properties: - - reg : 0 + - reg : 0 - Will enable all LED sync paths + 1 - Will enable the LED1 sync + 2 - Will enable the LED2 sync + 3 - Will enable the LED3 sync (LM36923 only) Optional child properties: - label : see Documentation/devicetree/bindings/leds/common.txt diff --git a/Documentation/devicetree/bindings/leds/leds-lt3593.txt b/Documentation/devicetree/bindings/leds/leds-lt3593.txt new file mode 100644 index 000000000000..6b2cabc36c0c --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-lt3593.txt @@ -0,0 +1,32 @@ +Bindings for Linear Technologies LT3593 LED controller + +Required properties: +- compatible: Should be "lltc,lt3593". +- lltc,ctrl-gpios: A handle to the GPIO that is connected to the 'CTRL' + pin of the chip. + +The hardware supports only one LED. The properties of this LED are +configured in a sub-node in the device node. + +Optional sub-node properties: +- label: A label for the LED. If none is given, the LED will be + named "lt3595::". +- linux,default-trigger: The default trigger for the LED. + See Documentation/devicetree/bindings/leds/common.txt +- default-state: The initial state of the LED. + See Documentation/devicetree/bindings/leds/common.txt + +If multiple chips of this type are found in a design, each one needs to +be handled by its own device node. + +Example: + +led-controller { + compatible = "lltc,lt3593"; + lltc,ctrl-gpios = <&gpio 0 GPIO_ACTIVE_HIGH>; + + led { + label = "white:backlight"; + default-state = "on"; + }; +}; |