NAME
gpioled —
GPIO LED generic device
driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your kernel configuration file:
device gpio
device gpioledDESCRIPTION
Thegpioled 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:
- hint.gpioled.%d.at
- The gpiobus you are attaching to. Normally assigned to gpiobus0.
- hint.gpioled.%d.name
- Arbitrary name of device in /dev/led/ to create for led(4).
- hint.gpioled.%d.pins
- 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).
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/boot/fdt/dts/bindings-gpio.txt.
The property name is the arbitrary name of the device in /dev/led/ to create for led(4).
SEE ALSO
HISTORY
The gpioled manual page first appeared in
FreeBSD 10.1.
AUTHORS
This manual page was written by Luiz Otavio O Souza.