From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- .../devicetree/bindings/input/adc-keys.txt | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/adc-keys.txt (limited to 'Documentation/devicetree/bindings/input/adc-keys.txt') diff --git a/Documentation/devicetree/bindings/input/adc-keys.txt b/Documentation/devicetree/bindings/input/adc-keys.txt new file mode 100644 index 000000000..e55181462 --- /dev/null +++ b/Documentation/devicetree/bindings/input/adc-keys.txt @@ -0,0 +1,49 @@ +ADC attached resistor ladder buttons +------------------------------------ + +Required properties: + - compatible: "adc-keys" + - io-channels: Phandle to an ADC channel + - io-channel-names = "buttons"; + - keyup-threshold-microvolt: Voltage at which all the keys are considered up. + +Optional properties: + - poll-interval: Poll interval time in milliseconds + - autorepeat: Boolean, Enable auto repeat feature of Linux input + subsystem. + +Each button (key) is represented as a sub-node of "adc-keys": + +Required subnode-properties: + - label: Descriptive name of the key. + - linux,code: Keycode to emit. + - press-threshold-microvolt: Voltage ADC input when this key is pressed. + +Example: + +#include + + adc-keys { + compatible = "adc-keys"; + io-channels = <&lradc 0>; + io-channel-names = "buttons"; + keyup-threshold-microvolt = <2000000>; + + button-up { + label = "Volume Up"; + linux,code = ; + press-threshold-microvolt = <1500000>; + }; + + button-down { + label = "Volume Down"; + linux,code = ; + press-threshold-microvolt = <1000000>; + }; + + button-enter { + label = "Enter"; + linux,code = ; + press-threshold-microvolt = <500000>; + }; + }; -- cgit v1.2.3