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Documentation / devicetree / bindings / leds / common.txt




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Based on kernel version 4.0. Page generated on 2015-04-14 21:21 EST.

1	Common leds properties.
2	
3	LED and flash LED devices provide the same basic functionality as current
4	regulators, but extended with LED and flash LED specific features like
5	blinking patterns, flash timeout, flash faults and external flash strobe mode.
6	
7	Many LED devices expose more than one current output that can be connected
8	to one or more discrete LED component. Since the arrangement of connections
9	can influence the way of the LED device initialization, the LED components
10	have to be tightly coupled with the LED device binding. They are represented
11	by child nodes of the parent LED device binding.
12	
13	Optional 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	
39	Examples:
40	
41	system-status {
42		label = "Status";
43		linux,default-trigger = "heartbeat";
44		...
45	};
46	
47	camera-flash {
48		label = "Flash";
49		led-sources = <0>, <1>;
50		max-microamp = <50000>;
51		flash-max-microamp = <320000>;
52		flash-timeout-us = <500000>;
53	};
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