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1Allwinner sun4i low res adc attached tablet keys
2------------------------------------------------
3
4Required properties:
5 - compatible: should be one of the following string:
6 "allwinner,sun4i-a10-lradc-keys"
7 "allwinner,sun8i-a83t-r-lradc"
8 "allwinner,sun50i-a64-lradc", "allwinner,sun8i-a83t-r-lradc"
9 - reg: mmio address range of the chip
10 - interrupts: interrupt to which the chip is connected
11 - vref-supply: powersupply for the lradc reference voltage
12
13Each key is represented as a sub-node of the compatible mentioned above:
14
15Required subnode-properties:
16 - label: Descriptive name of the key.
17 - linux,code: Keycode to emit.
18 - channel: Channel this key is attached to, must be 0 or 1.
19 - voltage: Voltage in µV at lradc input when this key is pressed.
20
21Example:
22
23#include <dt-bindings/input/input.h>
24
25 lradc: lradc@1c22800 {
26 compatible = "allwinner,sun4i-a10-lradc-keys";
27 reg = <0x01c22800 0x100>;
28 interrupts = <31>;
29 vref-supply = <®_vcc3v0>;
30
31 button@191 {
32 label = "Volume Up";
33 linux,code = <KEY_VOLUMEUP>;
34 channel = <0>;
35 voltage = <191274>;
36 };
37
38 button@392 {
39 label = "Volume Down";
40 linux,code = <KEY_VOLUMEDOWN>;
41 channel = <0>;
42 voltage = <392644>;
43 };
44
45 button@601 {
46 label = "Menu";
47 linux,code = <KEY_MENU>;
48 channel = <0>;
49 voltage = <601151>;
50 };
51
52 button@795 {
53 label = "Enter";
54 linux,code = <KEY_ENTER>;
55 channel = <0>;
56 voltage = <795090>;
57 };
58
59 button@987 {
60 label = "Home";
61 linux,code = <KEY_HOMEPAGE>;
62 channel = <0>;
63 voltage = <987387>;
64 };
65 };