rotary-encoder.txt (1923B)
1Rotary encoder DT bindings 2 3Required properties: 4- gpios: a spec for at least two GPIOs to be used, most significant first 5 6Optional 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 rollover when the rotary value becomes 16 greater than the specified steps or smaller than 0. For absolute axis only. 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 22- wakeup-source: Boolean, rotary encoder can wake up the system. 23- rotary-encoder,encoding: String, the method used to encode steps. 24 Supported are "gray" (the default and more common) and "binary". 25 26Deprecated 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 31See Documentation/input/devices/rotary-encoder.rst for more information. 32 33Example: 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 */ 39 rotary-encoder,encoding = "gray"; 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>; 48 rotary-encoder,encoding = "binary"; 49 rotary-encoder,rollover; 50 };