Add documentation for the adc-joystick driver, used to provide support for joysticks connected over ADC. Signed-off-by: Artur Rojek <contact@xxxxxxxxxxxxxx> Tested-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> --- .../bindings/input/adc-joystick.yaml | 100 ++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/adc-joystick.yaml diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml b/Documentation/devicetree/bindings/input/adc-joystick.yaml new file mode 100644 index 000000000000..97ae797348c7 --- /dev/null +++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml @@ -0,0 +1,100 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +# Copyright 2019-2020 Artur Rojek +%YAML 1.2 +--- +$id: "http://devicetree.org/schemas/bindings/input/adc-joystick.yaml#"; +$schema: "http://devicetree.org/meta-schemas/core.yaml#"; + +title: ADC attached joystick + +maintainers: + - Artur Rojek <contact@xxxxxxxxxxxxxx> + +description: | + Bindings for joystick devices connected to ADC controllers supporting + the Industrial I/O subsystem. + +properties: + compatible: + const: adc-joystick + + io-channels: + description: | + List of phandle and IIO specifier pairs. + Each pair defines one ADC channel to which a joystick axis is connected. + See Documentation/devicetree/bindings/iio/iio-bindings.txt for details. + +required: + - compatible + - io-channels + +additionalProperties: false + +patternProperties: + "^axis@([0-9])$": + type: object + description: | + Represents a joystick axis bound to the given ADC channel. + For each entry in the io-channels list, one axis subnode with a matching + index must be specified. + + properties: + linux,abs-code: + $ref: /schemas/types.yaml#/definitions/uint32 + description: EV_ABS specific event code generated by the axis. + + linux,abs-range: + $ref: /schemas/types.yaml#/definitions/uint32-array + items: + - description: minimum value + - description: maximum value + description: | + Minimum and maximum values produced by the axis. + For an ABS_X axis this will be the left-most and right-most + inclination of the joystick. If min > max, it is left to userspace to + treat the axis as inverted. + This property is interpreted as two signed 32 bit values. + + linux,abs-fuzz: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Amount of noise in the input value. + Omitting this property indicates the axis is precise. + + linux,abs-flat: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Axial "deadzone", or area around the center position, where the axis + is considered to be at rest. + Omitting this property indicates the axis always returns to exactly + the center position. + + required: + - linux,abs-code + - linux,abs-range + + additionalProperties: false + +examples: + - | + #include <dt-bindings/iio/adc/ingenic,adc.h> + #include <dt-bindings/input/input.h> + + joystick: adc-joystick { + compatible = "adc-joystick"; + io-channels = <&adc INGENIC_ADC_TOUCH_XP>, + <&adc INGENIC_ADC_TOUCH_YP>; + + axis@0 { + linux,abs-code = <ABS_X>; + linux,abs-range = <3300 0>; + linux,abs-fuzz = <4>; + linux,abs-flat = <200>; + }; + axis@1 { + linux,abs-code = <ABS_Y>; + linux,abs-range = <0 3300>; + linux,abs-fuzz = <4>; + linux,abs-flat = <200>; + }; + }; -- 2.24.1
