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: 14 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 $ref: /schemas/types.yaml#/definitions/string 81 82 oneOf: 83 - enum: 84 # LED will act as a back-light, controlled by the framebuffer system 85 - backlight 86 # LED will turn on (see also "default-state" property) 87 - default-on 88 # LED "double" flashes at a load average based rate 89 - heartbeat 90 # LED indicates disk activity 91 - disk-activity 92 # LED indicates disk read activity 93 - disk-read 94 # LED indicates disk write activity 95 - disk-write 96 # LED flashes at a fixed, configurable rate 97 - timer 98 # LED alters the brightness for the specified duration with one software 99 # timer (requires "led-pattern" property) 100 - pattern 101 # LED indicates mic mute state 102 - audio-micmute 103 # LED indicates audio mute state 104 - audio-mute 105 # LED indicates bluetooth power state 106 - bluetooth-power 107 # LED indicates camera flash state 108 - flash 109 # LED indicated keyboard capslock 110 - kbd-capslock 111 # LED indicates MTD memory activity 112 - mtd 113 # LED indicates NAND memory activity (deprecated), 114 # in new implementations use "mtd" 115 - nand-disk 116 # No trigger assigned to the LED. This is the default mode 117 # if trigger is absent 118 - none 119 # LED indicates camera torch state 120 - torch 121 # LED indicates USB gadget activity 122 - usb-gadget 123 # LED indicates USB host activity 124 - usb-host 125 # LED indicates USB port state 126 - usbport 127 # LED is triggered by CPU activity 128 - pattern: "^cpu[0-9]*$" 129 # LED is triggered by Bluetooth activity 130 - pattern: "^hci[0-9]+-power$" 131 # LED is triggered by SD/MMC activity 132 - pattern: "^mmc[0-9]+$" 133 # LED is triggered by WLAN activity 134 - pattern: "^phy[0-9]+tx$" 135 136 led-pattern: 137 description: | 138 Array of integers with default pattern for certain triggers. 139 140 Each trigger may parse this property differently: 141 - one-shot : two numbers specifying delay on and delay off (in ms), 142 - timer : two numbers specifying delay on and delay off (in ms), 143 - pattern : the pattern is given by a series of tuples, of 144 brightness and duration (in ms). The exact format is 145 described in: 146 Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt 147 $ref: /schemas/types.yaml#/definitions/uint32-matrix 148 items: 149 minItems: 2 150 maxItems: 2 151 152 led-max-microamp: 153 description: 154 Maximum LED supply current in microamperes. This property can be made 155 mandatory for the board configurations introducing a risk of hardware 156 damage in case an excessive current is set. 157 For flash LED controllers with configurable current this property is 158 mandatory for the LEDs in the non-flash modes (e.g. torch or indicator). 159 160 max-brightness: 161 description: 162 Normally, the maximum brightness is determined by the hardware, and this 163 property is not required. This property is used to set a software limit. 164 It could happen that an LED is made so bright that it gets damaged or 165 causes damage due to restrictions in a specific system, such as mounting 166 conditions. 167 Note that this flag is mainly used for PWM-LEDs, where it is not possible 168 to map brightness to current. Drivers for other controllers should use 169 led-max-microamp. 170 $ref: /schemas/types.yaml#/definitions/uint32 171 172 panic-indicator: 173 description: 174 This property specifies that the LED should be used, if at all possible, 175 as a panic indicator. 176 type: boolean 177 178 retain-state-shutdown: 179 description: 180 This property specifies that the LED should not be turned off or changed 181 when the system shuts down. 182 type: boolean 183 184 trigger-sources: 185 description: | 186 List of devices which should be used as a source triggering this LED 187 activity. Some LEDs can be related to a specific device and should somehow 188 indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0 189 port(s). 190 Another common example is switch or router with multiple Ethernet ports 191 each of them having its own LED assigned (assuming they are not 192 hardwired). In such cases this property should contain phandle(s) of 193 related source device(s). 194 Another example is a GPIO line that will be monitored and mirror the 195 state of the line (with or without inversion flags) to the LED. 196 In many cases LED can be related to more than one device (e.g. one USB LED 197 vs. multiple USB ports). Each source should be represented by a node in 198 the device tree and be referenced by a phandle and a set of phandle 199 arguments. A length of arguments should be specified by the 200 #trigger-source-cells property in the source node. 201 $ref: /schemas/types.yaml#/definitions/phandle-array 202 203 # Required properties for flash LED child nodes: 204 flash-max-microamp: 205 description: 206 Maximum flash LED supply current in microamperes. Required for flash LED 207 nodes with configurable current. 208 209 flash-max-timeout-us: 210 description: 211 Maximum timeout in microseconds after which the flash LED is turned off. 212 Required for flash LED nodes with configurable timeout. 213 214additionalProperties: true 215 216examples: 217 - | 218 #include <dt-bindings/gpio/gpio.h> 219 #include <dt-bindings/leds/common.h> 220 221 led-controller { 222 compatible = "gpio-leds"; 223 224 led-0 { 225 function = LED_FUNCTION_STATUS; 226 linux,default-trigger = "heartbeat"; 227 gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>; 228 }; 229 230 led-1 { 231 function = LED_FUNCTION_USB; 232 gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>; 233 trigger-sources = <&ohci_port1>, <&ehci_port1>; 234 }; 235 }; 236 237 - | 238 #include <dt-bindings/leds/common.h> 239 240 led-controller { 241 compatible = "maxim,max77693-led"; 242 243 led { 244 function = LED_FUNCTION_FLASH; 245 color = <LED_COLOR_ID_WHITE>; 246 led-sources = <0>, <1>; 247 led-max-microamp = <50000>; 248 flash-max-microamp = <320000>; 249 flash-max-timeout-us = <500000>; 250 }; 251 }; 252 253 - | 254 #include <dt-bindings/leds/common.h> 255 256 i2c { 257 #address-cells = <1>; 258 #size-cells = <0>; 259 260 led-controller@30 { 261 compatible = "panasonic,an30259a"; 262 reg = <0x30>; 263 #address-cells = <1>; 264 #size-cells = <0>; 265 266 led@1 { 267 reg = <1>; 268 linux,default-trigger = "heartbeat"; 269 function = LED_FUNCTION_INDICATOR; 270 function-enumerator = <1>; 271 }; 272 273 led@2 { 274 reg = <2>; 275 function = LED_FUNCTION_INDICATOR; 276 function-enumerator = <2>; 277 }; 278 279 led@3 { 280 reg = <3>; 281 function = LED_FUNCTION_INDICATOR; 282 function-enumerator = <3>; 283 }; 284 }; 285 }; 286 287... 288