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