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Rotary encoder DT bindings
Required properties:
- gpios: a spec for at least two GPIOs to be used, most significant first
Optional properties:
- linux,axis: the input subsystem axis to map to this rotary encoder.
Defaults to 0 (ABS_X / REL_X)
- rotary-encoder,steps: Number of steps in a full turnaround of the
encoder. Only relevant for absolute axis. Defaults to 24 which is a
typical value for such devices.
- rotary-encoder,relative-axis: register a relative axis rather than an
absolute one. Relative axis will only generate +1/-1 events on the input
device, hence no steps need to be passed.
- rotary-encoder,rollover: Automatic rollover when the rotary value becomes
greater than the specified steps or smaller than 0. For absolute axis only.
- rotary-encoder,steps-per-period: Number of steps (stable states) per period.
The values have the following meaning:
1: Full-period mode (default)
2: Half-period mode
4: Quarter-period mode
- wakeup-source: Boolean, rotary encoder can wake up the system.
- rotary-encoder,encoding: String, the method used to encode steps.
Supported are "gray" (the default and more common) and "binary".
Deprecated properties:
- rotary-encoder,half-period: Makes the driver work on half-period mode.
This property is deprecated. Instead, a 'steps-per-period ' value should
be used, such as "rotary-encoder,steps-per-period = <2>".
See Documentation/input/devices/rotary-encoder.rst for more information.
Example:
rotary@0 {
compatible = "rotary-encoder";
gpios = <&gpio 19 1>, <&gpio 20 0>; /* GPIO19 is inverted */
linux,axis = <0>; /* REL_X */
rotary-encoder,encoding = "gray";
rotary-encoder,relative-axis;
};
rotary@1 {
compatible = "rotary-encoder";
gpios = <&gpio 21 0>, <&gpio 22 0>;
linux,axis = <1>; /* ABS_Y */
rotary-encoder,steps = <24>;
rotary-encoder,encoding = "binary";
rotary-encoder,rollover;
};
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