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    oneOf:
83      - enum:
84            # LED will act as a back-light, controlled by the framebuffer system
85          - backlight
86            # LED will turn on (but for leds-gpio see "default-state" property in
87            # Documentation/devicetree/bindings/leds/leds-gpio.yaml)
88          - default-on
89            # LED "double" flashes at a load average based rate
90          - heartbeat
91            # LED indicates disk activity
92          - disk-activity
93            # LED indicates disk read activity
94          - disk-read
95            # LED indicates disk write activity
96          - disk-write
97            # LED flashes at a fixed, configurable rate
98          - timer
99            # LED alters the brightness for the specified duration with one software
100            # timer (requires "led-pattern" property)
101          - pattern
102            # LED indicates mic mute state
103          - audio-micmute
104            # LED indicates audio mute state
105          - audio-mute
106            # LED indicates bluetooth power state
107          - bluetooth-power
108            # LED indicates camera flash state
109          - flash
110            # LED indicated keyboard capslock
111          - kbd-capslock
112            # LED indicates MTD memory activity
113          - mtd
114            # LED indicates NAND memory activity (deprecated),
115            # in new implementations use "mtd"
116          - nand-disk
117            # No trigger assigned to the LED. This is the default mode
118            # if trigger is absent
119          - none
120            # LED indicates camera torch state
121          - torch
122            # LED indicates USB gadget activity
123          - usb-gadget
124            # LED indicates USB host activity
125          - usb-host
126            # LED indicates USB port state
127          - usbport
128        # LED is triggered by CPU activity
129      - pattern: "^cpu[0-9]*$"
130        # LED is triggered by Bluetooth activity
131      - pattern: "^hci[0-9]+-power$"
132        # LED is triggered by SD/MMC activity
133      - pattern: "^mmc[0-9]+$"
134        # LED is triggered by WLAN activity
135      - pattern: "^phy[0-9]+tx$"
136
137  led-pattern:
138    description: |
139      Array of integers with default pattern for certain triggers.
140
141      Each trigger may parse this property differently:
142        - one-shot : two numbers specifying delay on and delay off (in ms),
143        - timer : two numbers specifying delay on and delay off (in ms),
144        - pattern : the pattern is given by a series of tuples, of
145          brightness and duration (in ms).  The exact format is
146          described in:
147          Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
148    $ref: /schemas/types.yaml#/definitions/uint32-matrix
149    items:
150      minItems: 2
151      maxItems: 2
152
153  led-max-microamp:
154    description:
155      Maximum LED supply current in microamperes. This property can be made
156      mandatory for the board configurations introducing a risk of hardware
157      damage in case an excessive current is set.
158      For flash LED controllers with configurable current this property is
159      mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).
160
161  panic-indicator:
162    description:
163      This property specifies that the LED should be used, if at all possible,
164      as a panic indicator.
165    type: boolean
166
167  retain-state-shutdown:
168    description:
169      This property specifies that the LED should not be turned off or changed
170      when the system shuts down.
171    type: boolean
172
173  trigger-sources:
174    description: |
175      List of devices which should be used as a source triggering this LED
176      activity. Some LEDs can be related to a specific device and should somehow
177      indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
178      port(s).
179      Another common example is switch or router with multiple Ethernet ports
180      each of them having its own LED assigned (assuming they are not
181      hardwired). In such cases this property should contain phandle(s) of
182      related source device(s).
183      In many cases LED can be related to more than one device (e.g. one USB LED
184      vs. multiple USB ports). Each source should be represented by a node in
185      the device tree and be referenced by a phandle and a set of phandle
186      arguments. A length of arguments should be specified by the
187      #trigger-source-cells property in the source node.
188    $ref: /schemas/types.yaml#/definitions/phandle-array
189
190  # Required properties for flash LED child nodes:
191  flash-max-microamp:
192    description:
193      Maximum flash LED supply current in microamperes. Required for flash LED
194      nodes with configurable current.
195
196  flash-max-timeout-us:
197    description:
198      Maximum timeout in microseconds after which the flash LED is turned off.
199      Required for flash LED nodes with configurable timeout.
200
201additionalProperties: true
202
203examples:
204  - |
205    #include <dt-bindings/gpio/gpio.h>
206    #include <dt-bindings/leds/common.h>
207
208    led-controller {
209        compatible = "gpio-leds";
210
211        led-0 {
212            function = LED_FUNCTION_STATUS;
213            linux,default-trigger = "heartbeat";
214            gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
215        };
216
217        led-1 {
218            function = LED_FUNCTION_USB;
219            gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
220            trigger-sources = <&ohci_port1>, <&ehci_port1>;
221        };
222    };
223
224  - |
225    #include <dt-bindings/leds/common.h>
226
227    led-controller {
228        compatible = "maxim,max77693-led";
229
230        led {
231            function = LED_FUNCTION_FLASH;
232            color = <LED_COLOR_ID_WHITE>;
233            led-sources = <0>, <1>;
234            led-max-microamp = <50000>;
235            flash-max-microamp = <320000>;
236            flash-max-timeout-us = <500000>;
237        };
238    };
239
240  - |
241    #include <dt-bindings/leds/common.h>
242
243    i2c {
244        #address-cells = <1>;
245        #size-cells = <0>;
246
247        led-controller@30 {
248            compatible = "panasonic,an30259a";
249            reg = <0x30>;
250            #address-cells = <1>;
251            #size-cells = <0>;
252
253            led@1 {
254                reg = <1>;
255                linux,default-trigger = "heartbeat";
256                function = LED_FUNCTION_INDICATOR;
257                function-enumerator = <1>;
258            };
259
260            led@2 {
261                reg = <2>;
262                function = LED_FUNCTION_INDICATOR;
263                function-enumerator = <2>;
264            };
265
266            led@3 {
267                reg = <3>;
268                function = LED_FUNCTION_INDICATOR;
269                function-enumerator = <3>;
270            };
271        };
272    };
273
274...
275