[deliverable/linux.git] / Documentation / devicetree / bindings / input / rotary-encoder.txt

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 rollove 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/rotary-encoder.txt 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;
		};
Commit	Line	Data
80c99bcd DM	1	Rotary encoder DT bindings
	2
	3	Required properties:
7dde4e74	4	- gpios: a spec for at least two GPIOs to be used, most significant first
80c99bcd DM	5
	6	Optional properties:
	7	- linux,axis: the input subsystem axis to map to this rotary encoder.
	8	Defaults to 0 (ABS_X / REL_X)
	9	- rotary-encoder,steps: Number of steps in a full turnaround of the
	10	encoder. Only relevant for absolute axis. Defaults to 24 which is a
	11	typical value for such devices.
	12	- rotary-encoder,relative-axis: register a relative axis rather than an
	13	absolute one. Relative axis will only generate +1/-1 events on the input
	14	device, hence no steps need to be passed.
	15	- rotary-encoder,rollover: Automatic rollove when the rotary value becomes
	16	greater than the specified steps or smaller than 0. For absolute axis only.
3a341a4c EG	17	- rotary-encoder,steps-per-period: Number of steps (stable states) per period.
	18	The values have the following meaning:
	19	1: Full-period mode (default)
	20	2: Half-period mode
	21	4: Quarter-period mode
47ec6e5a	22	- wakeup-source: Boolean, rotary encoder can wake up the system.
d205a218 UKK	23	- rotary-encoder,encoding: String, the method used to encode steps.
d205a218 UKK	24	Supported are "gray" (the default and more common) and "binary".
80c99bcd	25
3a341a4c EG	26	Deprecated properties:
	27	- rotary-encoder,half-period: Makes the driver work on half-period mode.
	28	This property is deprecated. Instead, a 'steps-per-period ' value should
	29	be used, such as "rotary-encoder,steps-per-period = <2>".
	30
80c99bcd DM	31	See Documentation/input/rotary-encoder.txt for more information.
	32
	33	Example:
	34
	35	rotary@0 {
	36	compatible = "rotary-encoder";
	37	gpios = <&gpio 19 1>, <&gpio 20 0>; /* GPIO19 is inverted */
	38	linux,axis = <0>; /* REL_X */
d205a218	39	rotary-encoder,encoding = "gray";
80c99bcd DM	40	rotary-encoder,relative-axis;
	41	};
	42
	43	rotary@1 {
	44	compatible = "rotary-encoder";
	45	gpios = <&gpio 21 0>, <&gpio 22 0>;
	46	linux,axis = <1>; /* ABS_Y */
	47	rotary-encoder,steps = <24>;
d205a218	48	rotary-encoder,encoding = "binary";
80c99bcd DM	49	rotary-encoder,rollover;
80c99bcd DM	50	};