Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
GPIOLED(4)	       FreeBSD Kernel Interfaces Manual		    GPIOLED(4)

     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	writ-
     ing to this device	as described in	led(4).

     On	a device.hints(5) based	system,	like MIPS, these values	are config-
     urable for	gpioled:	    The	gpiobus	you are	attaching to.  Normally	as-
			    signed to gpiobus0.   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 in-
			    stance.  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.

     hint.gpioled.%d.state  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	{


	     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

     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.

FreeBSD	13.0			 May 23, 2019			  FreeBSD 13.0


Want to link to this manual page? Use this URL:

home | help