1 * GPIO driven matrix keypad device tree bindings
2
3 GPIO driven matrix keypad is used to interface a SoC with a matrix keypad.
4 The matrix keypad supports multiple row and column lines, a key can be
5 placed at each intersection of a unique row and a unique column. The matrix
6 keypad can sense a key-press and key-release by means of GPIO lines and
7 report the event using GPIO interrupts to the cpu.
8
9 Required Properties:
10 - compatible: Should be "gpio-matrix-keypad"
11 - row-gpios: List of gpios used as row lines. The gpio specifier
12 for this property depends on the gpio controller to
13 which these row lines are connected.
14 - col-gpios: List of gpios used as column lines. The gpio specifier
15 for this property depends on the gpio controller to
16 which these column lines are connected.
17 - linux,keymap: The definition can be found at
18 bindings/input/matrix-keymap.txt
19
20 Optional Properties:
21 - linux,no-autorepeat: do no enable autorepeat feature.
22 - wakeup-source: use any event on keypad as wakeup event.
23 (Legacy property supported: "linux,wakeup")
24 - debounce-delay-ms: debounce interval in milliseconds
25 - col-scan-delay-us: delay, measured in microseconds, that is needed
26 before we can scan keypad after activating column gpio
27 - drive-inactive-cols: drive inactive columns during scan,
28 default is to turn inactive columns into inputs.
29
30 Example:
31 matrix-keypad {
32 compatible = "gpio-matrix-keypad";
33 debounce-delay-ms = <5>;
34 col-scan-delay-us = <2>;
35
36 row-gpios = <&gpio2 25 0
37 &gpio2 26 0
38 &gpio2 27 0>;
39
40 col-gpios = <&gpio2 21 0
41 &gpio2 22 0>;
42
43 linux,keymap = <0x0000008B
44 0x0100009E
45 0x02000069
46 0x0001006A
47 0x0101001C
48 0x0201006C>;
49 };
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