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 taken from the node 18 name (excluding the unit address). It has to uniquely identify 19 a device, i.e. no other LED class device can be assigned the same 20 label. 21 22- linux,default-trigger : This parameter, if present, is a 23 string defining the trigger assigned to the LED. Current triggers are: 24 "backlight" - LED will act as a back-light, controlled by the framebuffer 25 system 26 "default-on" - LED will turn on (but for leds-gpio see "default-state" 27 property in Documentation/devicetree/bindings/gpio/led.txt) 28 "heartbeat" - LED "double" flashes at a load average based rate 29 "ide-disk" - LED indicates disk activity 30 "timer" - LED flashes at a fixed, configurable rate 31 32- led-max-microamp : Maximum LED supply current in microamperes. This property 33 can be made mandatory for the board configurations 34 introducing a risk of hardware damage in case an excessive 35 current is set. 36 For flash LED controllers with configurable current this 37 property is mandatory for the LEDs in the non-flash modes 38 (e.g. torch or indicator). 39 40Required properties for flash LED child nodes: 41- flash-max-microamp : Maximum flash LED supply current in microamperes. 42- flash-max-timeout-us : Maximum timeout in microseconds after which the flash 43 LED is turned off. 44 45For controllers that have no configurable current the flash-max-microamp 46property can be omitted. 47For controllers that have no configurable timeout the flash-max-timeout-us 48property can be omitted. 49 50Examples: 51 52system-status { 53 label = "Status"; 54 linux,default-trigger = "heartbeat"; 55 ... 56}; 57 58camera-flash { 59 label = "Flash"; 60 led-sources = <0>, <1>; 61 led-max-microamp = <50000>; 62 flash-max-microamp = <320000>; 63 flash-max-timeout-us = <500000>; 64}; 65