From 5ac76bad2277ed40f2a2112ffab0f156e3b599fb Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 23 Jun 2015 15:38:46 -0600 Subject: dm: led: Add a driver for GPIO-controlled LEDs Add a simple driver which allows use of LEDs attached to GPIOs. The linux device tree binding is used. Signed-off-by: Simon Glass --- doc/device-tree-bindings/leds/leds-gpio.txt | 52 +++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 doc/device-tree-bindings/leds/leds-gpio.txt (limited to 'doc/device-tree-bindings/leds') diff --git a/doc/device-tree-bindings/leds/leds-gpio.txt b/doc/device-tree-bindings/leds/leds-gpio.txt new file mode 100644 index 0000000000..df1b3080f6 --- /dev/null +++ b/doc/device-tree-bindings/leds/leds-gpio.txt @@ -0,0 +1,52 @@ +LEDs connected to GPIO lines + +Required properties: +- compatible : should be "gpio-leds". + +Each LED is represented as a sub-node of the gpio-leds device. Each +node's name represents the name of the corresponding LED. + +LED sub-node properties: +- gpios : Should specify the LED's GPIO, see "gpios property" in + Documentation/devicetree/bindings/gpio/gpio.txt. Active low LEDs should be + indicated using flags in the GPIO specifier. +- label : (optional) + see Documentation/devicetree/bindings/leds/common.txt +- linux,default-trigger : (optional) + see Documentation/devicetree/bindings/leds/common.txt +- default-state: (optional) The initial state of the LED. Valid + values are "on", "off", and "keep". If the LED is already on or off + and the default-state property is set the to same value, then no + glitch should be produced where the LED momentarily turns off (or + on). The "keep" setting will keep the LED at whatever its current + state is, without producing a glitch. The default is off if this + property is not present. + +Examples: + +leds { + compatible = "gpio-leds"; + hdd { + label = "IDE Activity"; + gpios = <&mcu_pio 0 1>; /* Active low */ + linux,default-trigger = "ide-disk"; + }; + + fault { + gpios = <&mcu_pio 1 0>; + /* Keep LED on if BIOS detected hardware fault */ + default-state = "keep"; + }; +}; + +run-control { + compatible = "gpio-leds"; + red { + gpios = <&mpc8572 6 0>; + default-state = "off"; + }; + green { + gpios = <&mpc8572 7 0>; + default-state = "on"; + }; +}; -- cgit v1.2.3