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    enum:
83        # LED will act as a back-light, controlled by the framebuffer system
84      - backlight
85        # LED will turn on (but for leds-gpio see "default-state" property in
86        # Documentation/devicetree/bindings/leds/leds-gpio.yaml)
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 IDE disk activity (deprecated), in new implementations
93        # use "disk-activity"
94      - ide-disk
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
101  led-pattern:
102    description: |
103      Array of integers with default pattern for certain triggers.
104
105      Each trigger may parse this property differently:
106        - one-shot : two numbers specifying delay on and delay off (in ms),
107        - timer : two numbers specifying delay on and delay off (in ms),
108        - pattern : the pattern is given by a series of tuples, of
109          brightness and duration (in ms).  The exact format is
110          described in:
111          Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
112    $ref: /schemas/types.yaml#/definitions/uint32-matrix
113    items:
114      minItems: 2
115      maxItems: 2
116
117  led-max-microamp:
118    description:
119      Maximum LED supply current in microamperes. This property can be made
120      mandatory for the board configurations introducing a risk of hardware
121      damage in case an excessive current is set.
122      For flash LED controllers with configurable current this property is
123      mandatory for the LEDs in the non-flash modes (e.g. torch or indicator).
124
125  panic-indicator:
126    description:
127      This property specifies that the LED should be used, if at all possible,
128      as a panic indicator.
129    type: boolean
130
131  trigger-sources:
132    description: |
133      List of devices which should be used as a source triggering this LED
134      activity. Some LEDs can be related to a specific device and should somehow
135      indicate its state. E.g. USB 2.0 LED may react to device(s) in a USB 2.0
136      port(s).
137      Another common example is switch or router with multiple Ethernet ports
138      each of them having its own LED assigned (assuming they are not
139      hardwired). In such cases this property should contain phandle(s) of
140      related source device(s).
141      In many cases LED can be related to more than one device (e.g. one USB LED
142      vs. multiple USB ports). Each source should be represented by a node in
143      the device tree and be referenced by a phandle and a set of phandle
144      arguments. A length of arguments should be specified by the
145      #trigger-source-cells property in the source node.
146    $ref: /schemas/types.yaml#/definitions/phandle-array
147
148  # Required properties for flash LED child nodes:
149  flash-max-microamp:
150    description:
151      Maximum flash LED supply current in microamperes. Required for flash LED
152      nodes with configurable current.
153
154  flash-max-timeout-us:
155    description:
156      Maximum timeout in microseconds after which the flash LED is turned off.
157      Required for flash LED nodes with configurable timeout.
158
159additionalProperties: true
160
161examples:
162  - |
163    #include <dt-bindings/gpio/gpio.h>
164    #include <dt-bindings/leds/common.h>
165
166    led-controller {
167        compatible = "gpio-leds";
168
169        led-0 {
170            function = LED_FUNCTION_STATUS;
171            linux,default-trigger = "heartbeat";
172            gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
173        };
174
175        led-1 {
176            function = LED_FUNCTION_USB;
177            gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
178            trigger-sources = <&ohci_port1>, <&ehci_port1>;
179        };
180    };
181
182    led-controller@0 {
183        compatible = "maxim,max77693-led";
184        reg = <0 0x100>;
185
186        led {
187            function = LED_FUNCTION_FLASH;
188            color = <LED_COLOR_ID_WHITE>;
189            led-sources = <0>, <1>;
190            led-max-microamp = <50000>;
191            flash-max-microamp = <320000>;
192            flash-max-timeout-us = <500000>;
193        };
194    };
195
196    i2c {
197        #address-cells = <1>;
198        #size-cells = <0>;
199
200        led-controller@30 {
201            compatible = "panasonic,an30259a";
202            reg = <0x30>;
203            #address-cells = <1>;
204            #size-cells = <0>;
205
206            led@1 {
207                reg = <1>;
208                linux,default-trigger = "heartbeat";
209                function = LED_FUNCTION_INDICATOR;
210                function-enumerator = <1>;
211            };
212
213            led@2 {
214                reg = <2>;
215                function = LED_FUNCTION_INDICATOR;
216                function-enumerator = <2>;
217            };
218
219            led@3 {
220                reg = <3>;
221                function = LED_FUNCTION_INDICATOR;
222                function-enumerator = <3>;
223            };
224        };
225    };
226
227...
228