xref: /linux/Documentation/devicetree/bindings/input/google,cros-ec-keyb.yaml (revision e80b500370e71b8cd7dd64be4080cee0a3e5068f) 
1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2%YAML 1.2
3---
4
5$id: http://devicetree.org/schemas/input/google,cros-ec-keyb.yaml#
6$schema: http://devicetree.org/meta-schemas/core.yaml#
7
8title: ChromeOS EC Keyboard
9
10maintainers:
11  - Simon Glass <sjg@chromium.org>
12  - Benson Leung <bleung@chromium.org>
13
14description: |
15  Google's ChromeOS EC Keyboard is a simple matrix keyboard
16  implemented on a separate EC (Embedded Controller) device. It provides
17  a message for reading key scans from the EC. These are then converted
18  into keycodes for processing by the kernel. This device also supports
19  switches/buttons like power and volume buttons.
20
21properties:
22  compatible:
23    oneOf:
24      - description: ChromeOS EC with only buttons/switches
25        const: google,cros-ec-keyb-switches
26      - description: ChromeOS EC with keyboard and possibly buttons/switches
27        const: google,cros-ec-keyb
28
29  google,needs-ghost-filter:
30    description:
31      Enable a ghost filter for the matrix keyboard. This is recommended
32      if the EC does not have its own logic or hardware for this.
33    type: boolean
34
35  function-row-physmap:
36    $ref: /schemas/types.yaml#/definitions/uint32-array
37    minItems: 1
38    maxItems: 15
39    description: |
40      An ordered u32 array describing the rows/columns (in the scan matrix)
41      of top row keys from physical left (KEY_F1) to right. Each entry
42      encodes the row/column as:
43      (((row) & 0xFF) << 24) | (((column) & 0xFF) << 16)
44      where the lower 16 bits are reserved. This property is specified only
45      when the keyboard has a custom design for the top row keys.
46
47dependencies:
48  function-row-physmap: [ 'linux,keymap' ]
49  google,needs-ghost-filter: [ 'linux,keymap' ]
50
51required:
52  - compatible
53
54if:
55  properties:
56    compatible:
57      contains:
58        const: google,cros-ec-keyb
59then:
60  $ref: /schemas/input/matrix-keymap.yaml#
61  required:
62    - keypad,num-rows
63    - keypad,num-columns
64    - linux,keymap
65
66unevaluatedProperties: false
67
68examples:
69  - |
70    #include <dt-bindings/input/input.h>
71    keyboard-controller {
72        compatible = "google,cros-ec-keyb";
73        keypad,num-rows = <8>;
74        keypad,num-columns = <13>;
75        google,needs-ghost-filter;
76        function-row-physmap = <
77            MATRIX_KEY(0x00, 0x02, 0)   /* T1 */
78            MATRIX_KEY(0x03, 0x02, 0)   /* T2 */
79            MATRIX_KEY(0x02, 0x02, 0)   /* T3 */
80            MATRIX_KEY(0x01, 0x02, 0)   /* T4 */
81            MATRIX_KEY(0x03, 0x04, 0)   /* T5 */
82            MATRIX_KEY(0x02, 0x04, 0)   /* T6 */
83            MATRIX_KEY(0x01, 0x04, 0)   /* T7 */
84            MATRIX_KEY(0x02, 0x09, 0)   /* T8 */
85            MATRIX_KEY(0x01, 0x09, 0)   /* T9 */
86            MATRIX_KEY(0x00, 0x04, 0)   /* T10 */
87        >;
88        /*
89         * Keymap entries take the form of 0xRRCCKKKK where
90         * RR=Row CC=Column KKKK=Key Code
91         * The values below are for a US keyboard layout and
92         * are taken from the Linux driver. Note that the
93         * 102ND key is not used for US keyboards.
94         */
95        linux,keymap = <
96            /* CAPSLCK F1         B          F10     */
97            0x0001003a 0x0002003b 0x00030030 0x00040044
98            /* N       =          R_ALT      ESC     */
99            0x00060031 0x0008000d 0x000a0064 0x01010001
100            /* F4      G          F7         H       */
101            0x0102003e 0x01030022 0x01040041 0x01060023
102            /* '       F9         BKSPACE    L_CTRL  */
103            0x01080028 0x01090043 0x010b000e 0x0200001d
104            /* TAB     F3         T          F6      */
105            0x0201000f 0x0202003d 0x02030014 0x02040040
106            /* ]       Y          102ND      [       */
107            0x0205001b 0x02060015 0x02070056 0x0208001a
108            /* F8      GRAVE      F2         5       */
109            0x02090042 0x03010029 0x0302003c 0x03030006
110            /* F5      6          -          \       */
111            0x0304003f 0x03060007 0x0308000c 0x030b002b
112            /* R_CTRL  A          D          F       */
113            0x04000061 0x0401001e 0x04020020 0x04030021
114            /* S       K          J          ;       */
115            0x0404001f 0x04050025 0x04060024 0x04080027
116            /* L       ENTER      Z          C       */
117            0x04090026 0x040b001c 0x0501002c 0x0502002e
118            /* V       X          ,          M       */
119            0x0503002f 0x0504002d 0x05050033 0x05060032
120            /* L_SHIFT /          .          SPACE   */
121            0x0507002a 0x05080035 0x05090034 0x050B0039
122            /* 1       3          4          2       */
123            0x06010002 0x06020004 0x06030005 0x06040003
124            /* 8       7          0          9       */
125            0x06050009 0x06060008 0x0608000b 0x0609000a
126            /* L_ALT   DOWN       RIGHT      Q       */
127            0x060a0038 0x060b006c 0x060c006a 0x07010010
128            /* E       R          W          I       */
129            0x07020012 0x07030013 0x07040011 0x07050017
130            /* U       R_SHIFT    P          O       */
131            0x07060016 0x07070036 0x07080019 0x07090018
132            /* UP      LEFT    */
133            0x070b0067 0x070c0069>;
134    };
135  - |
136    /* No matrix keyboard, just buttons/switches */
137    keyboard-controller {
138        compatible = "google,cros-ec-keyb-switches";
139    };
140...
141