Re: [PATCH v4 1/2] input: adc-keys: add DT binding documentation

From: Rob Herring
Date: Sat Jul 16 2016 - 18:11:47 EST


On Tue, Jul 12, 2016 at 09:36:25PM +0200, Alexandre Belloni wrote:
> Add documentation for ADC keys
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
> ---
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
>
> Changes v2..v4:
> - Documented autorepeat and poll-interval
>
>
> .../devicetree/bindings/input/adc-keys.txt | 50 ++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
> create mode 100644 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 000000000000..6f26ad75ed2b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/adc-keys.txt
> @@ -0,0 +1,50 @@
> +ADC attached resistor ladder buttons
> +------------------------------------
> +
> +Required properties:
> + - compatible: "adc-keys"
> + - io-channels: Phandle to an ADC channel
> + - io-channel-names = "buttons";
> + - keyup-threshold-mvolt: Voltage at which all the keys are considered up.

'-microvolt' is the standard suffix.

> +
> +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-mvolt: Voltage adc input when this key is pressed.
> +
> +Example:
> +
> +#include <dt-bindings/input/input.h>
> +
> + adc-keys {
> + compatible = "adc-keys";
> + io-channels = <&lradc 0>;
> + io-channel-names = "buttons";
> + keyup-threshold-mvolt = <2000>;
> +
> + button@1500 {
> + label = "Volume Up";
> + linux,code = <KEY_VOLUMEUP>;
> + press-threshold-mvolt = <1500>;
> + };
> +
> + button@1000 {
> + label = "Volume Down";
> + linux,code = <KEY_VOLUMEDOWN>;
> + press-threshold-mvolt = <1000>;
> + };
> +
> + button@500 {
> + label = "Enter";
> + linux,code = <KEY_ENTER>;
> + press-threshold-mvolt = <500>;
> + };
> + };
> +
> --
> 2.8.1
>