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    $ref: /schemas/types.yaml#/definitions/string
81
82    oneOf:
83      - enum:
84            # LED will act as a back-light, controlled by the framebuffer system
85          - backlight
86            # LED will turn on (but for leds-gpio see "default-state" property in
87            # Documentation/devicetree/bindings/leds/leds-gpio.yaml)
88          - default-on
89            # LED "double" flashes at a load average based rate
90          - heartbeat
91            # LED indicates disk activity
92          - disk-activity
93          - disk-read
94          - disk-write
95            # LED indicates IDE disk activity (deprecated), in new implementations
96            # use "disk-activity"
97          - ide-disk
98            # LED flashes at a fixed, configurable rate
99          - timer
100            # LED alters the brightness for the specified duration with one software
101            # timer (requires "led-pattern" property)
102          - pattern
103          - usb-gadget
104          - usb-host
105      - pattern: "^cpu[0-9]*$"
106      - pattern: "^hci[0-9]+-power$"
107        # LED is triggered by Bluetooth activity
108      - pattern: "^mmc[0-9]+$"
109        # LED is triggered by SD/MMC activity
110      - pattern: "^phy[0-9]+tx$"
111        # LED is triggered by WLAN activity
112
113  led-pattern:
114    description: |
115      Array of integers with default pattern for certain triggers.
116
117      Each trigger may parse this property differently:
118        - one-shot : two numbers specifying delay on and delay off (in ms),
119        - timer : two numbers specifying delay on and delay off (in ms),
120        - pattern : the pattern is given by a series of tuples, of
121          brightness and duration (in ms).  The exact format is
122          described in:
123          Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
124    $ref: /schemas/types.yaml#/definitions/uint32-matrix
125    items:
126      minItems: 2
127      maxItems: 2
128
129  led-max-microamp:
130    description:
131      Maximum LED supply current in microamperes. This property can be made
132      mandatory for the board configurations introducing a risk of hardware
133      damage in case an excessive current is set.
134      For flash LED controllers with configurable current this property is
135      mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).
136
137  panic-indicator:
138    description:
139      This property specifies that the LED should be used, if at all possible,
140      as a panic indicator.
141    type: boolean
142
143  retain-state-shutdown:
144    description:
145      This property specifies that the LED should not be turned off or changed
146      when the system shuts down.
147    type: boolean
148
149  trigger-sources:
150    description: |
151      List of devices which should be used as a source triggering this LED
152      activity. Some LEDs can be related to a specific device and should somehow
153      indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
154      port(s).
155      Another common example is switch or router with multiple Ethernet ports
156      each of them having its own LED assigned (assuming they are not
157      hardwired). In such cases this property should contain phandle(s) of
158      related source device(s).
159      In many cases LED can be related to more than one device (e.g. one USB LED
160      vs. multiple USB ports). Each source should be represented by a node in
161      the device tree and be referenced by a phandle and a set of phandle
162      arguments. A length of arguments should be specified by the
163      #trigger-source-cells property in the source node.
164    $ref: /schemas/types.yaml#/definitions/phandle-array
165
166  # Required properties for flash LED child nodes:
167  flash-max-microamp:
168    description:
169      Maximum flash LED supply current in microamperes. Required for flash LED
170      nodes with configurable current.
171
172  flash-max-timeout-us:
173    description:
174      Maximum timeout in microseconds after which the flash LED is turned off.
175      Required for flash LED nodes with configurable timeout.
176
177additionalProperties: true
178
179examples:
180  - |
181    #include <dt-bindings/gpio/gpio.h>
182    #include <dt-bindings/leds/common.h>
183
184    led-controller {
185        compatible = "gpio-leds";
186
187        led-0 {
188            function = LED_FUNCTION_STATUS;
189            linux,default-trigger = "heartbeat";
190            gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
191        };
192
193        led-1 {
194            function = LED_FUNCTION_USB;
195            gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
196            trigger-sources = <&ohci_port1>, <&ehci_port1>;
197        };
198    };
199
200  - |
201    #include <dt-bindings/leds/common.h>
202
203    led-controller {
204        compatible = "maxim,max77693-led";
205
206        led {
207            function = LED_FUNCTION_FLASH;
208            color = <LED_COLOR_ID_WHITE>;
209            led-sources = <0>, <1>;
210            led-max-microamp = <50000>;
211            flash-max-microamp = <320000>;
212            flash-max-timeout-us = <500000>;
213        };
214    };
215
216  - |
217    #include <dt-bindings/leds/common.h>
218
219    i2c {
220        #address-cells = <1>;
221        #size-cells = <0>;
222
223        led-controller@30 {
224            compatible = "panasonic,an30259a";
225            reg = <0x30>;
226            #address-cells = <1>;
227            #size-cells = <0>;
228
229            led@1 {
230                reg = <1>;
231                linux,default-trigger = "heartbeat";
232                function = LED_FUNCTION_INDICATOR;
233                function-enumerator = <1>;
234            };
235
236            led@2 {
237                reg = <2>;
238                function = LED_FUNCTION_INDICATOR;
239                function-enumerator = <2>;
240            };
241
242            led@3 {
243                reg = <3>;
244                function = LED_FUNCTION_INDICATOR;
245                function-enumerator = <3>;
246            };
247        };
248    };
249
250...
251