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 activity of all CPUs
109          - cpu
110            # LED indicates camera flash state
111          - flash
112            # LED indicated keyboard capslock
113          - kbd-capslock
114            # LED indicates MTD memory activity
115          - mtd
116            # LED indicates NAND memory activity (deprecated),
117            # in new implementations use "mtd"
118          - nand-disk
119            # No trigger assigned to the LED. This is the default mode
120            # if trigger is absent
121          - none
122            # LED indicates camera torch state
123          - torch
124            # LED indicates USB gadget activity
125          - usb-gadget
126            # LED indicates USB host activity
127          - usb-host
128            # LED indicates USB port state
129          - usbport
130        # LED is triggered by CPU activity
131      - pattern: "^cpu[0-9]*$"
132        # LED is triggered by Bluetooth activity
133      - pattern: "^hci[0-9]+-power$"
134        # LED is triggered by SD/MMC activity
135      - pattern: "^mmc[0-9]+$"
136        # LED is triggered by WLAN activity
137      - pattern: "^phy[0-9]+tx$"
138
139  led-pattern:
140    description: |
141      Array of integers with default pattern for certain triggers.
142
143      Each trigger may parse this property differently:
144        - one-shot : two numbers specifying delay on and delay off (in ms),
145        - timer : two numbers specifying delay on and delay off (in ms),
146        - pattern : the pattern is given by a series of tuples, of
147          brightness and duration (in ms).  The exact format is
148          described in:
149          Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
150    $ref: /schemas/types.yaml#/definitions/uint32-matrix
151    items:
152      minItems: 2
153      maxItems: 2
154
155  led-max-microamp:
156    description:
157      Maximum LED supply current in microamperes. This property can be made
158      mandatory for the board configurations introducing a risk of hardware
159      damage in case an excessive current is set.
160      For flash LED controllers with configurable current this property is
161      mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).
162
163  panic-indicator:
164    description:
165      This property specifies that the LED should be used, if at all possible,
166      as a panic indicator.
167    type: boolean
168
169  retain-state-shutdown:
170    description:
171      This property specifies that the LED should not be turned off or changed
172      when the system shuts down.
173    type: boolean
174
175  trigger-sources:
176    description: |
177      List of devices which should be used as a source triggering this LED
178      activity. Some LEDs can be related to a specific device and should somehow
179      indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
180      port(s).
181      Another common example is switch or router with multiple Ethernet ports
182      each of them having its own LED assigned (assuming they are not
183      hardwired). In such cases this property should contain phandle(s) of
184      related source device(s).
185      In many cases LED can be related to more than one device (e.g. one USB LED
186      vs. multiple USB ports). Each source should be represented by a node in
187      the device tree and be referenced by a phandle and a set of phandle
188      arguments. A length of arguments should be specified by the
189      #trigger-source-cells property in the source node.
190    $ref: /schemas/types.yaml#/definitions/phandle-array
191
192  # Required properties for flash LED child nodes:
193  flash-max-microamp:
194    description:
195      Maximum flash LED supply current in microamperes. Required for flash LED
196      nodes with configurable current.
197
198  flash-max-timeout-us:
199    description:
200      Maximum timeout in microseconds after which the flash LED is turned off.
201      Required for flash LED nodes with configurable timeout.
202
203additionalProperties: true
204
205examples:
206  - |
207    #include <dt-bindings/gpio/gpio.h>
208    #include <dt-bindings/leds/common.h>
209
210    led-controller {
211        compatible = "gpio-leds";
212
213        led-0 {
214            function = LED_FUNCTION_STATUS;
215            linux,default-trigger = "heartbeat";
216            gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
217        };
218
219        led-1 {
220            function = LED_FUNCTION_USB;
221            gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
222            trigger-sources = <&ohci_port1>, <&ehci_port1>;
223        };
224    };
225
226  - |
227    #include <dt-bindings/leds/common.h>
228
229    led-controller {
230        compatible = "maxim,max77693-led";
231
232        led {
233            function = LED_FUNCTION_FLASH;
234            color = <LED_COLOR_ID_WHITE>;
235            led-sources = <0>, <1>;
236            led-max-microamp = <50000>;
237            flash-max-microamp = <320000>;
238            flash-max-timeout-us = <500000>;
239        };
240    };
241
242  - |
243    #include <dt-bindings/leds/common.h>
244
245    i2c {
246        #address-cells = <1>;
247        #size-cells = <0>;
248
249        led-controller@30 {
250            compatible = "panasonic,an30259a";
251            reg = <0x30>;
252            #address-cells = <1>;
253            #size-cells = <0>;
254
255            led@1 {
256                reg = <1>;
257                linux,default-trigger = "heartbeat";
258                function = LED_FUNCTION_INDICATOR;
259                function-enumerator = <1>;
260            };
261
262            led@2 {
263                reg = <2>;
264                function = LED_FUNCTION_INDICATOR;
265                function-enumerator = <2>;
266            };
267
268            led@3 {
269                reg = <3>;
270                function = LED_FUNCTION_INDICATOR;
271                function-enumerator = <3>;
272            };
273        };
274    };
275
276...
277