1# SPDX-License-Identifier: GPL-2.0-only 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/leds/common.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Common leds properties 8 9maintainers: 10 - Jacek Anaszewski <jacek.anaszewski@gmail.com> 11 - Pavel Machek <pavel@ucw.cz> 12 13description: 14 LED and flash LED devices provide the same basic functionality as current 15 regulators, but extended with LED and flash LED specific features like 16 blinking patterns, flash timeout, flash faults and external flash strobe mode. 17 18 Many LED devices expose more than one current output that can be connected 19 to one or more discrete LED component. Since the arrangement of connections 20 can influence the way of the LED device initialization, the LED components 21 have to be tightly coupled with the LED device binding. They are represented 22 by child nodes of the parent LED device binding. 23 24properties: 25 led-sources: 26 description: 27 List of device current outputs the LED is connected to. The outputs are 28 identified by the numbers that must be defined in the LED device binding 29 documentation. 30 $ref: /schemas/types.yaml#/definitions/uint32-array 31 32 function: 33 description: 34 LED function. Use one of the LED_FUNCTION_* prefixed definitions 35 from the header include/dt-bindings/leds/common.h. If there is no 36 matching LED_FUNCTION available, add a new one. 37 $ref: /schemas/types.yaml#/definitions/string 38 39 color: 40 description: 41 Color of the LED. Use one of the LED_COLOR_ID_* prefixed definitions from 42 the header include/dt-bindings/leds/common.h. If there is no matching 43 LED_COLOR_ID available, add a new one. 44 $ref: /schemas/types.yaml#/definitions/uint32 45 minimum: 0 46 maximum: 9 47 48 function-enumerator: 49 description: 50 Integer to be used when more than one instance of the same function is 51 needed, differing only with an ordinal number. 52 $ref: /schemas/types.yaml#/definitions/uint32 53 54 label: 55 description: 56 The label for this LED. If omitted, the label is taken from the node name 57 (excluding the unit address). It has to uniquely identify a device, i.e. 58 no other LED class device can be assigned the same label. This property is 59 deprecated - use 'function' and 'color' properties instead. 60 function-enumerator has no effect when this property is present. 61 62 default-state: 63 description: 64 The initial state of the LED. If the LED is already on or off and the 65 default-state property is set the to same value, then no glitch should be 66 produced where the LED momentarily turns off (or on). The "keep" setting 67 will keep the LED at whatever its current state is, without producing a 68 glitch. 69 $ref: /schemas/types.yaml#/definitions/string 70 enum: 71 - on 72 - off 73 - keep 74 default: off 75 76 linux,default-trigger: 77 description: 78 This parameter, if present, is a string defining the trigger assigned to 79 the LED. 80 $ref: /schemas/types.yaml#/definitions/string 81 82 enum: 83 # LED will act as a back-light, controlled by the framebuffer system 84 - backlight 85 # LED will turn on (but for leds-gpio see "default-state" property in 86 # Documentation/devicetree/bindings/leds/leds-gpio.yaml) 87 - default-on 88 # LED "double" flashes at a load average based rate 89 - heartbeat 90 # LED indicates disk activity 91 - disk-activity 92 # LED indicates IDE disk activity (deprecated), in new implementations 93 # use "disk-activity" 94 - ide-disk 95 # LED flashes at a fixed, configurable rate 96 - timer 97 # LED alters the brightness for the specified duration with one software 98 # timer (requires "led-pattern" property) 99 - pattern 100 101 led-pattern: 102 description: | 103 Array of integers with default pattern for certain triggers. 104 105 Each trigger may parse this property differently: 106 - one-shot : two numbers specifying delay on and delay off (in ms), 107 - timer : two numbers specifying delay on and delay off (in ms), 108 - pattern : the pattern is given by a series of tuples, of 109 brightness and duration (in ms). The exact format is 110 described in: 111 Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt 112 $ref: /schemas/types.yaml#/definitions/uint32-matrix 113 items: 114 minItems: 2 115 maxItems: 2 116 117 led-max-microamp: 118 description: 119 Maximum LED supply current in microamperes. This property can be made 120 mandatory for the board configurations introducing a risk of hardware 121 damage in case an excessive current is set. 122 For flash LED controllers with configurable current this property is 123 mandatory for the LEDs in the non-flash modes (e.g. torch or indicator). 124 125 panic-indicator: 126 description: 127 This property specifies that the LED should be used, if at all possible, 128 as a panic indicator. 129 type: boolean 130 131 retain-state-shutdown: 132 description: 133 This property specifies that the LED should not be turned off or changed 134 when the system shuts down. 135 type: boolean 136 137 trigger-sources: 138 description: | 139 List of devices which should be used as a source triggering this LED 140 activity. Some LEDs can be related to a specific device and should somehow 141 indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0 142 port(s). 143 Another common example is switch or router with multiple Ethernet ports 144 each of them having its own LED assigned (assuming they are not 145 hardwired). In such cases this property should contain phandle(s) of 146 related source device(s). 147 In many cases LED can be related to more than one device (e.g. one USB LED 148 vs. multiple USB ports). Each source should be represented by a node in 149 the device tree and be referenced by a phandle and a set of phandle 150 arguments. A length of arguments should be specified by the 151 #trigger-source-cells property in the source node. 152 $ref: /schemas/types.yaml#/definitions/phandle-array 153 154 # Required properties for flash LED child nodes: 155 flash-max-microamp: 156 description: 157 Maximum flash LED supply current in microamperes. Required for flash LED 158 nodes with configurable current. 159 160 flash-max-timeout-us: 161 description: 162 Maximum timeout in microseconds after which the flash LED is turned off. 163 Required for flash LED nodes with configurable timeout. 164 165additionalProperties: true 166 167examples: 168 - | 169 #include <dt-bindings/gpio/gpio.h> 170 #include <dt-bindings/leds/common.h> 171 172 led-controller { 173 compatible = "gpio-leds"; 174 175 led-0 { 176 function = LED_FUNCTION_STATUS; 177 linux,default-trigger = "heartbeat"; 178 gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>; 179 }; 180 181 led-1 { 182 function = LED_FUNCTION_USB; 183 gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>; 184 trigger-sources = <&ohci_port1>, <&ehci_port1>; 185 }; 186 }; 187 188 led-controller@0 { 189 compatible = "maxim,max77693-led"; 190 reg = <0 0x100>; 191 192 led { 193 function = LED_FUNCTION_FLASH; 194 color = <LED_COLOR_ID_WHITE>; 195 led-sources = <0>, <1>; 196 led-max-microamp = <50000>; 197 flash-max-microamp = <320000>; 198 flash-max-timeout-us = <500000>; 199 }; 200 }; 201 202 i2c { 203 #address-cells = <1>; 204 #size-cells = <0>; 205 206 led-controller@30 { 207 compatible = "panasonic,an30259a"; 208 reg = <0x30>; 209 #address-cells = <1>; 210 #size-cells = <0>; 211 212 led@1 { 213 reg = <1>; 214 linux,default-trigger = "heartbeat"; 215 function = LED_FUNCTION_INDICATOR; 216 function-enumerator = <1>; 217 }; 218 219 led@2 { 220 reg = <2>; 221 function = LED_FUNCTION_INDICATOR; 222 function-enumerator = <2>; 223 }; 224 225 led@3 { 226 reg = <3>; 227 function = LED_FUNCTION_INDICATOR; 228 function-enumerator = <3>; 229 }; 230 }; 231 }; 232 233... 234