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 to the 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 $ref: /schemas/types.yaml#/definitions/string 81 82 oneOf: 83 - enum: 84 # LED will act as a back-light, controlled by the framebuffer system 85 - backlight 86 # LED will turn on (see also "default-state" property) 87 - default-on 88 # LED "double" flashes at a load average based rate 89 - heartbeat 90 # LED indicates disk activity 91 - disk-activity 92 # LED indicates disk read activity 93 - disk-read 94 # LED indicates disk write activity 95 - disk-write 96 # LED flashes at a fixed, configurable rate 97 - timer 98 # LED alters the brightness for the specified duration with one software 99 # timer (requires "led-pattern" property) 100 - pattern 101 # LED indicates mic mute state 102 - audio-micmute 103 # LED indicates audio mute state 104 - audio-mute 105 # LED indicates bluetooth power state 106 - bluetooth-power 107 # LED indicates camera flash state 108 - flash 109 # LED indicated keyboard capslock 110 - kbd-capslock 111 # LED indicates MTD memory activity 112 - mtd 113 # LED indicates NAND memory activity (deprecated), 114 # in new implementations use "mtd" 115 - nand-disk 116 # LED indicates network activity 117 - netdev 118 # No trigger assigned to the LED. This is the default mode 119 # if trigger is absent 120 - none 121 # LED indicates remote control feedback 122 - rc-feedback 123 # LED indicates camera torch state 124 - torch 125 # LED indicates USB gadget activity 126 - usb-gadget 127 # LED indicates USB host activity 128 - usb-host 129 # LED indicates USB port state 130 - usbport 131 # LED is triggered by CPU activity 132 - pattern: "^cpu[0-9]*$" 133 # LED is triggered by Bluetooth activity 134 - pattern: "^hci[0-9]+-power$" 135 # LED is triggered by SD/MMC activity 136 - pattern: "^mmc[0-9]+$" 137 # LED is triggered by WLAN activity 138 - pattern: "^phy[0-9]+tx$" 139 140 led-pattern: 141 description: | 142 Array of integers with default pattern for certain triggers. 143 144 Each trigger may parse this property differently: 145 - one-shot : two numbers specifying delay on and delay off (in ms), 146 - timer : two numbers specifying delay on and delay off (in ms), 147 - pattern : the pattern is given by a series of tuples, of 148 brightness and duration (in ms). The exact format is 149 described in: 150 Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt 151 $ref: /schemas/types.yaml#/definitions/uint32-matrix 152 items: 153 minItems: 2 154 maxItems: 2 155 156 led-max-microamp: 157 description: 158 Maximum LED supply current in microamperes. This property can be made 159 mandatory for the board configurations introducing a risk of hardware 160 damage in case an excessive current is set. 161 For flash LED controllers with configurable current this property is 162 mandatory for the LEDs in the non-flash modes (e.g. torch or indicator). 163 164 max-brightness: 165 description: 166 Normally, the maximum brightness is determined by the hardware, and this 167 property is not required. This property is used to set a software limit. 168 It could happen that an LED is made so bright that it gets damaged or 169 causes damage due to restrictions in a specific system, such as mounting 170 conditions. 171 Note that this flag is mainly used for PWM-LEDs, where it is not possible 172 to map brightness to current. Drivers for other controllers should use 173 led-max-microamp. 174 $ref: /schemas/types.yaml#/definitions/uint32 175 176 default-brightness: 177 description: 178 Brightness to be set if LED's default state is on. Used only during 179 initialization. If the option is not set then max brightness is used. 180 $ref: /schemas/types.yaml#/definitions/uint32 181 182 panic-indicator: 183 description: 184 This property specifies that the LED should be used, if at all possible, 185 as a panic indicator. 186 type: boolean 187 188 retain-state-shutdown: 189 description: 190 This property specifies that the LED should not be turned off or changed 191 when the system shuts down. 192 type: boolean 193 194 trigger-sources: 195 description: | 196 List of devices which should be used as a source triggering this LED 197 activity. Some LEDs can be related to a specific device and should somehow 198 indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0 199 port(s). 200 Another common example is switch or router with multiple Ethernet ports 201 each of them having its own LED assigned (assuming they are not 202 hardwired). In such cases this property should contain phandle(s) of 203 related source device(s). 204 Another example is a GPIO line that will be monitored and mirror the 205 state of the line (with or without inversion flags) to the LED. 206 In many cases LED can be related to more than one device (e.g. one USB LED 207 vs. multiple USB ports). Each source should be represented by a node in 208 the device tree and be referenced by a phandle and a set of phandle 209 arguments. A length of arguments should be specified by the 210 #trigger-source-cells property in the source node. 211 $ref: /schemas/types.yaml#/definitions/phandle-array 212 213 active-high: 214 type: boolean 215 description: 216 Makes LED active high. To turn the LED ON, line needs to be 217 set to high voltage instead of low. 218 219 active-low: 220 type: boolean 221 description: 222 Makes LED active low. To turn the LED ON, line needs to be 223 set to low voltage instead of high. 224 225 inactive-high-impedance: 226 type: boolean 227 description: 228 Set LED to high-impedance mode to turn the LED OFF. LED might also 229 describe this mode as tristate. 230 231 # Required properties for flash LED child nodes: 232 flash-max-microamp: 233 description: 234 Maximum flash LED supply current in microamperes. Required for flash LED 235 nodes with configurable current. 236 237 flash-max-timeout-us: 238 description: 239 Maximum timeout in microseconds after which the flash LED is turned off. 240 Required for flash LED nodes with configurable timeout. 241 242allOf: 243 - if: 244 required: 245 - active-low 246 then: 247 properties: 248 active-high: false 249 250additionalProperties: true 251 252examples: 253 - | 254 #include <dt-bindings/gpio/gpio.h> 255 #include <dt-bindings/leds/common.h> 256 257 led-controller { 258 compatible = "gpio-leds"; 259 260 led-0 { 261 function = LED_FUNCTION_STATUS; 262 linux,default-trigger = "heartbeat"; 263 gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>; 264 }; 265 266 led-1 { 267 function = LED_FUNCTION_USB; 268 gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>; 269 trigger-sources = <&ohci_port1>, <&ehci_port1>; 270 }; 271 }; 272 273 - | 274 #include <dt-bindings/leds/common.h> 275 276 led-controller { 277 compatible = "maxim,max77693-led"; 278 279 led { 280 function = LED_FUNCTION_FLASH; 281 color = <LED_COLOR_ID_WHITE>; 282 led-sources = <0>, <1>; 283 led-max-microamp = <50000>; 284 flash-max-microamp = <320000>; 285 flash-max-timeout-us = <500000>; 286 }; 287 }; 288 289 - | 290 #include <dt-bindings/leds/common.h> 291 292 i2c { 293 #address-cells = <1>; 294 #size-cells = <0>; 295 296 led-controller@30 { 297 compatible = "panasonic,an30259a"; 298 reg = <0x30>; 299 #address-cells = <1>; 300 #size-cells = <0>; 301 302 led@1 { 303 reg = <1>; 304 linux,default-trigger = "heartbeat"; 305 function = LED_FUNCTION_INDICATOR; 306 function-enumerator = <1>; 307 }; 308 309 led@2 { 310 reg = <2>; 311 function = LED_FUNCTION_INDICATOR; 312 function-enumerator = <2>; 313 }; 314 315 led@3 { 316 reg = <3>; 317 function = LED_FUNCTION_INDICATOR; 318 function-enumerator = <3>; 319 }; 320 }; 321 }; 322 323... 324