1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 %YAML 1.2
3 ---
4 $id: http://devicetree.org/schemas/input/rotary-encoder.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6
7 title: Rotary encoder
8
9 maintainers:
10 - Frank Li <Frank.Li@nxp.com>
11
12 description:
13 See Documentation/input/devices/rotary-encoder.rst for more information.
14
15 properties:
16 compatible:
17 const: rotary-encoder
18
19 gpios:
20 minItems: 2
21
22 linux,axis:
23 default: 0
24 description:
25 the input subsystem axis to map to this rotary encoder.
26 Defaults to 0 (ABS_X / REL_X)
27
28 rotary-encoder,steps:
29 $ref: /schemas/types.yaml#/definitions/uint32
30 default: 24
31 description:
32 Number of steps in a full turnaround of the
33 encoder. Only relevant for absolute axis. Defaults to 24 which is a
34 typical value for such devices.
35
36 rotary-encoder,relative-axis:
37 $ref: /schemas/types.yaml#/definitions/flag
38 description:
39 register a relative axis rather than an
40 absolute one. Relative axis will only generate +1/-1 events on the input
41 device, hence no steps need to be passed.
42
43 rotary-encoder,rollover:
44 $ref: /schemas/types.yaml#/definitions/int32
45 description:
46 Automatic rollover when the rotary value becomes
47 greater than the specified steps or smaller than 0. For absolute axis only.
48
49 rotary-encoder,steps-per-period:
50 $ref: /schemas/types.yaml#/definitions/uint32
51 default: 1
52 enum: [1, 2, 4]
53 description: |
54 Number of steps (stable states) per period.
55 The values have the following meaning:
56 1: Full-period mode (default)
57 2: Half-period mode
58 4: Quarter-period mode
59
60 wakeup-source: true
61
62 rotary-encoder,encoding:
63 $ref: /schemas/types.yaml#/definitions/string
64 description: the method used to encode steps.
65 enum: [gray, binary]
66
67 rotary-encoder,half-period:
68 $ref: /schemas/types.yaml#/definitions/flag
69 deprecated: true
70 description:
71 Makes the driver work on half-period mode.
72 This property is deprecated. Instead, a 'steps-per-period ' value should
73 be used, such as "rotary-encoder,steps-per-period = <2>".
74
75 required:
76 - compatible
77 - gpios
78
79 additionalProperties: false
80
81 examples:
82 - |
83 rotary {
84 compatible = "rotary-encoder";
85 gpios = <&gpio 19 1>, <&gpio 20 0>; /* GPIO19 is inverted */
86 linux,axis = <0>; /* REL_X */
87 rotary-encoder,encoding = "gray";
88 rotary-encoder,relative-axis;
89 };
90
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