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    $ref: /schemas/types.yaml#/definitions/string
81
82    oneOf:
83      - enum:
84            # LED will act as a back-light, controlled by the framebuffer system
85          - backlight
86            # LED will turn on (but for leds-gpio see "default-state" property in
87            # Documentation/devicetree/bindings/leds/leds-gpio.yaml)
88          - default-on
89            # LED "double" flashes at a load average based rate
90          - heartbeat
91            # LED indicates disk activity
92          - disk-activity
93          - disk-read
94          - disk-write
95            # LED flashes at a fixed, configurable rate
96          - timer
97            # LED alters the brightness for the specified duration with one software
98            # timer (requires "led-pattern" property)
99          - pattern
100          - usb-gadget
101          - usb-host
102      - pattern: "^cpu[0-9]*$"
103      - pattern: "^hci[0-9]+-power$"
104        # LED is triggered by Bluetooth activity
105      - pattern: "^mmc[0-9]+$"
106        # LED is triggered by SD/MMC activity
107      - pattern: "^phy[0-9]+tx$"
108        # LED is triggered by WLAN activity
109
110  led-pattern:
111    description: |
112      Array of integers with default pattern for certain triggers.
113
114      Each trigger may parse this property differently:
115        - one-shot : two numbers specifying delay on and delay off (in ms),
116        - timer : two numbers specifying delay on and delay off (in ms),
117        - pattern : the pattern is given by a series of tuples, of
118          brightness and duration (in ms).  The exact format is
119          described in:
120          Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
121    $ref: /schemas/types.yaml#/definitions/uint32-matrix
122    items:
123      minItems: 2
124      maxItems: 2
125
126  led-max-microamp:
127    description:
128      Maximum LED supply current in microamperes. This property can be made
129      mandatory for the board configurations introducing a risk of hardware
130      damage in case an excessive current is set.
131      For flash LED controllers with configurable current this property is
132      mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).
133
134  panic-indicator:
135    description:
136      This property specifies that the LED should be used, if at all possible,
137      as a panic indicator.
138    type: boolean
139
140  retain-state-shutdown:
141    description:
142      This property specifies that the LED should not be turned off or changed
143      when the system shuts down.
144    type: boolean
145
146  trigger-sources:
147    description: |
148      List of devices which should be used as a source triggering this LED
149      activity. Some LEDs can be related to a specific device and should somehow
150      indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
151      port(s).
152      Another common example is switch or router with multiple Ethernet ports
153      each of them having its own LED assigned (assuming they are not
154      hardwired). In such cases this property should contain phandle(s) of
155      related source device(s).
156      In many cases LED can be related to more than one device (e.g. one USB LED
157      vs. multiple USB ports). Each source should be represented by a node in
158      the device tree and be referenced by a phandle and a set of phandle
159      arguments. A length of arguments should be specified by the
160      #trigger-source-cells property in the source node.
161    $ref: /schemas/types.yaml#/definitions/phandle-array
162
163  # Required properties for flash LED child nodes:
164  flash-max-microamp:
165    description:
166      Maximum flash LED supply current in microamperes. Required for flash LED
167      nodes with configurable current.
168
169  flash-max-timeout-us:
170    description:
171      Maximum timeout in microseconds after which the flash LED is turned off.
172      Required for flash LED nodes with configurable timeout.
173
174additionalProperties: true
175
176examples:
177  - |
178    #include <dt-bindings/gpio/gpio.h>
179    #include <dt-bindings/leds/common.h>
180
181    led-controller {
182        compatible = "gpio-leds";
183
184        led-0 {
185            function = LED_FUNCTION_STATUS;
186            linux,default-trigger = "heartbeat";
187            gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
188        };
189
190        led-1 {
191            function = LED_FUNCTION_USB;
192            gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
193            trigger-sources = <&ohci_port1>, <&ehci_port1>;
194        };
195    };
196
197  - |
198    #include <dt-bindings/leds/common.h>
199
200    led-controller {
201        compatible = "maxim,max77693-led";
202
203        led {
204            function = LED_FUNCTION_FLASH;
205            color = <LED_COLOR_ID_WHITE>;
206            led-sources = <0>, <1>;
207            led-max-microamp = <50000>;
208            flash-max-microamp = <320000>;
209            flash-max-timeout-us = <500000>;
210        };
211    };
212
213  - |
214    #include <dt-bindings/leds/common.h>
215
216    i2c {
217        #address-cells = <1>;
218        #size-cells = <0>;
219
220        led-controller@30 {
221            compatible = "panasonic,an30259a";
222            reg = <0x30>;
223            #address-cells = <1>;
224            #size-cells = <0>;
225
226            led@1 {
227                reg = <1>;
228                linux,default-trigger = "heartbeat";
229                function = LED_FUNCTION_INDICATOR;
230                function-enumerator = <1>;
231            };
232
233            led@2 {
234                reg = <2>;
235                function = LED_FUNCTION_INDICATOR;
236                function-enumerator = <2>;
237            };
238
239            led@3 {
240                reg = <3>;
241                function = LED_FUNCTION_INDICATOR;
242                function-enumerator = <3>;
243            };
244        };
245    };
246
247...
248