dt-bindings: input: ti,twl4030-keypad: convert to DT schema

Convert the legacy TXT binding for the TWL4030 keypad module
to the modern YAML DT schema format. This adds formal validation
and improves documentation by inheriting from the matrix-keymap schema.

Signed-off-by: Jihed Chaibi <[e-mail]>
Reviewed-by: Rob Herring (Arm) <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Dmitry Torokhov <[e-mail]>

Documentation/devicetree/bindings/input/ti,twl4030-keypad.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/ti,twl4030-keypad.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Texas Instruments TWL4030-family Keypad Controller
+
+maintainers:
+  - Peter Ujfalusi <[e-mail]>
+
+description:
+  TWL4030's Keypad controller is used to interface a SoC with a matrix-type
+  keypad device. The keypad controller supports multiple row and column lines.
+  A key can be placed at each intersection of a unique row and a unique column.
+  The keypad controller can sense a key-press and key-release and report the
+  event using a interrupt to the cpu.
+
+allOf:
+  - $ref: matrix-keymap.yaml#
+
+properties:
+  compatible:
+    const: ti,twl4030-keypad
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - interrupts
+  - keypad,num-rows
+  - keypad,num-columns
+  - linux,keymap
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/input/input.h>
+
+    keypad {
+        compatible = "ti,twl4030-keypad";
+        interrupts = <1>;
+        keypad,num-rows = <8>;
+        keypad,num-columns = <8>;
+        linux,keymap = <
+            /* row 0 */
+            MATRIX_KEY(0, 0, KEY_1)
+            MATRIX_KEY(0, 1, KEY_2)
+            MATRIX_KEY(0, 2, KEY_3)
+
+            /* ...and so on for a full 8x8 matrix... */
+
+            /* row 7 */
+            MATRIX_KEY(7, 6, KEY_Y)
+            MATRIX_KEY(7, 7, KEY_Z)
+        >;
+    };

Documentation/devicetree/bindings/input/twl4030-keypad.txt

···
-* TWL4030's Keypad Controller device tree bindings
-
-TWL4030's Keypad controller is used to interface a SoC with a matrix-type
-keypad device. The keypad controller supports multiple row and column lines.
-A key can be placed at each intersection of a unique row and a unique column.
-The keypad controller can sense a key-press and key-release and report the
-event using a interrupt to the cpu.
-
-This binding is based on the matrix-keymap binding with the following
-changes:
-
- * keypad,num-rows and keypad,num-columns are required.
-
-Required SoC Specific Properties:
-- compatible: should be one of the following
-   - "ti,twl4030-keypad": For controllers compatible with twl4030 keypad
-      controller.
-- interrupt: should be one of the following
-   - <1>: For controllers compatible with twl4030 keypad controller.
-
-Example:
-	twl_keypad: keypad {
-		compatible = "ti,twl4030-keypad";
-		interrupts = <1>;
-		keypad,num-rows = <8>;
-		keypad,num-columns = <8>;
-	};