xref: /linux/Documentation/devicetree/bindings/leds/common.txt (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1Common leds properties.
2
3LED and flash LED devices provide the same basic functionality as current
4regulators, but extended with LED and flash LED specific features like
5blinking patterns, flash timeout, flash faults and external flash strobe mode.
6
7Many LED devices expose more than one current output that can be connected
8to one or more discrete LED component. Since the arrangement of connections
9can influence the way of the LED device initialization, the LED components
10have to be tightly coupled with the LED device binding. They are represented
11by child nodes of the parent LED device binding.
12
13Optional properties for child nodes:
14- led-sources : List of device current outputs the LED is connected to. The
15		outputs are identified by the numbers that must be defined
16		in the LED device binding documentation.
17- label : The label for this LED.  If omitted, the label is
18  taken from the node name (excluding the unit address).
19
20- linux,default-trigger :  This parameter, if present, is a
21    string defining the trigger assigned to the LED.  Current triggers are:
22     "backlight" - LED will act as a back-light, controlled by the framebuffer
23		   system
24     "default-on" - LED will turn on (but for leds-gpio see "default-state"
25		    property in Documentation/devicetree/bindings/gpio/led.txt)
26     "heartbeat" - LED "double" flashes at a load average based rate
27     "ide-disk" - LED indicates disk activity
28     "timer" - LED flashes at a fixed, configurable rate
29
30- max-microamp : maximum intensity in microamperes of the LED
31		 (torch LED for flash devices)
32- flash-max-microamp : maximum intensity in microamperes of the
33                       flash LED; it is mandatory if the LED should
34		       support the flash mode
35- flash-timeout-us : timeout in microseconds after which the flash
36                     LED is turned off
37
38
39Examples:
40
41system-status {
42	label = "Status";
43	linux,default-trigger = "heartbeat";
44	...
45};
46
47camera-flash {
48	label = "Flash";
49	led-sources = <0>, <1>;
50	max-microamp = <50000>;
51	flash-max-microamp = <320000>;
52	flash-timeout-us = <500000>;
53};
54