Documentation/devicetree/bindings/input/sun4i-lradc-keys.txt

   1 Allwinner sun4i low res adc attached tablet keys
   2 ------------------------------------------------
   3
   4 Required 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
  13 Each key is represented as a sub-node of the compatible mentioned above:
  14
  15 Required 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
  21 Example:
  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 = <&reg_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         };