dt-bindings: input: convert rotary-encoder to yaml

Convert binding doc rotary-encoder.txt to yaml format.

Additional change:
- Only keep one example.

Fix below warning:
arch/arm64/boot/dts/freescale/imx8mn-dimonoff-gateway-evk.dtb: /rotary-encoder:
    failed to match any schema with compatible: ['rotary-encoder']

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20240811214656.3773098-1-Frank.Li@nxp.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: nxpfrankli

Documentation/devicetree/bindings/input/rotary-encoder.txt

@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/rotary-encoder.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Rotary encoder
+
+maintainers:
+  - Frank Li <Frank.Li@nxp.com>
+
+description:
+  See Documentation/input/devices/rotary-encoder.rst for more information.
+
+properties:
+  compatible:
+    const: rotary-encoder
+
+  gpios:
+    minItems: 2
+
+  linux,axis:
+    default: 0
+    description:
+      the input subsystem axis to map to this rotary encoder.
+      Defaults to 0 (ABS_X / REL_X)
+
+  rotary-encoder,steps:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 24
+    description:
+      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:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      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:
+    $ref: /schemas/types.yaml#/definitions/int32
+    description:
+      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:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 1
+    enum: [1, 2, 4]
+    description: |
+      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: true
+
+  rotary-encoder,encoding:
+    $ref: /schemas/types.yaml#/definitions/string
+    description: the method used to encode steps.
+    enum: [gray, binary]
+
+  rotary-encoder,half-period:
+    $ref: /schemas/types.yaml#/definitions/flag
+    deprecated: true
+    description:
+      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>".
+
+required:
+  - compatible
+  - gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    rotary {
+        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;
+    };
+