Re: [PATCH 4/5] dt-bindings: input: Add docs for ADC driven joystick.
From: Rob Herring <robh@kernel.org>
Date: 2020-01-08 20:12:32
Also in:
linux-iio, linux-input, lkml
On Sun, Jan 05, 2020 at 01:16:38AM +0100, Artur Rojek wrote:
quoted hunk ↗ jump to hunk
Add documentation for the adc-joystick driver, used to provide support for joysticks connected over ADC. Signed-off-by: Artur Rojek <redacted> Tested-by: Paul Cercueil <paul@crapouillou.net> --- .../bindings/input/adc-joystick.yaml | 100 ++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/adc-joystick.yamldiff --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@artur-rojek.eu> + +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])$":
A unit-address means there should be a 'reg' property. I'd just do axis-x and axis-y instead.
+ 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.
Existing 'linux,code' should be used here.
+ + linux,abs-range:
Drop 'linux,' here and on the rest of these.
+ $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