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Manual Pages  — GPIOLED


gpioled – GPIO LED generic device driver



To compile this driver into the kernel, place the following lines in your kernel configuration file: device gpio device gpioled


The gpioled driver provides glue to attach a led(4) compatible device to a GPIO pin. Each LED in the system has a name which is used to export a device as /dev/led/<name>. The GPIO pin can then be controlled by writing to this device as described in led(4).

On a device.hints(5) based system, like MIPS, these values are configurable for gpioled:
  The gpiobus you are attaching to. Normally assigned to gpiobus0.
  Arbitrary name of device in /dev/led/ to create for led(4).
  Which pin on the GPIO interface to map to this instance. Please note that this mask should only ever have one bit set (any other bits - i.e., pins - will be ignored).
  If set to 1, the pin will be set to 0 to light the LED, and 1 to clear it.
  The initial state of the LED when the driver takes control over it. If set to 1 or 0, the LED will be on or off correspondingly. If set to -1, the LED will be kept in its original state.

On a FDT(4) based system, like ARM, the DTS part for a gpioled device usually looks like:

gpio: gpio {

        gpio-controller;         ...

        led0 {                 compatible = "gpioled";                 gpios = <&gpio 16 2 0>;         /* GPIO pin 16. */                 name = "ok";         };

        led1 {                 compatible = "gpioled";                 gpios = <&gpio 17 2 0>;         /* GPIO pin 17. */                 name = "user-led1";         }; };

Optionally, you can choose to combine all the LEDs under a single "gpio-leds" compatible node:

simplebus0 {


        leds {                 compatible = "gpio-leds";

                led0 {                         gpios = <&gpio 16 2 0>;                         name = "ok"                 };

                led1 {                         gpios = <&gpio 17 2 0>;                         name = "user-led1"                 };         }; };

Both methods are equally supported and it is possible to have the LEDs defined with any sort of mix between the methods. The only restriction is that a GPIO pin cannot be mapped by two different (gpio)leds.

For more details about the gpios property, please consult /usr/src/sys/dts/bindings-gpio.txt.

The property name is the arbitrary name of the device in /dev/led/ to create for led(4).


fdt(4), gpio(4), gpioiic(4), led(4)


The gpioled manual page first appeared in FreeBSD 10.1 .


This manual page was written by Luiz Otavio O Souza.

GPIOLED (4) May 23, 2019

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