[PATCH 4/4] dt-bindings: input: mt-matrix-keypad: add guardian mt matrix keypad bindings definition

[<Gireesh.Hiremath@in.bosch.com>]

From: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>

Add binding definition for the support of the Guardian
mt matrix keypad driver.

Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>
---
 .../bindings/input/mt-matrix-keypad.yaml      | 134 ++++++++++++++++++
 1 file changed, 134 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/mt-matrix-keypad.yaml

diff --git a/Documentation/devicetree/bindings/input/mt-matrix-keypad.yaml b/Documentation/devicetree/bindings/input/mt-matrix-keypad.yaml
new file mode 100644
index 000000000000..b52cd478f638
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/mt-matrix-keypad.yaml
@@ -0,0 +1,134 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/mt-matrix-keypad.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO driven mt matrix keypad device tree bindings
+
+maintainers:
+  - vinay <VinayKumar.Shettar@in.bosch.com>
+
+description: |
+  GPIO driven mt matrix keypad is used to interface a SoC with a mt matrix
+  keypad. The mt matrix keypad supports multiple gpio line, all gpio line act
+  as row as wel as column lines, a key can be placed at each intersection
+  of a unique row number not equal to a unique column and they are diagonally
+  symmetric.
+
+  Example- For 5 gpio lines, possible matrix is 5x5 and maximum possible
+        keys are 10.
+
+        Sample matrix table for 7 button and 5 gpio line
+
+        ------------------------------------------------------
+        |Row\Col |GPIO 0 | GPIO 1 | GPIO 2 | GPIO 3 | GPIO 4 |
+        ------------------------------------------------------
+        | GPIO 0 |  X    | KEY_9  | KEY_2  |   X    | KEY_1  |
+        ------------------------------------------------------
+        | GPIO 1 | KEY_9 |  X     | KEY_6  |   X    |  X     |
+        ------------------------------------------------------
+        | GPIO 2 | KEY_2 | KEY_6  |  X     | KEY_4  | KEY_7  |
+        ------------------------------------------------------
+        | GPIO 3 |  X    |  X     | KEY_4  |  X     | KEY_8  |
+        ------------------------------------------------------
+        | GPIO 4 | KEY_1 |  X     | KEY_7  | KEY_8  |  X     |
+        ------------------------------------------------------
+        X - invalid key
+        KEY_x - preferred key code
+
+  The mt matrix keypad can sense a key-press and key-release by means of GPIO
+  lines and report the event using GPIO interrupts to the cpu.
+
+properties:
+  compatible:
+    oneOf:
+      - const: gpio-mt-matrix-keypad
+      - items:
+          - enum:
+              - gpio-mt-matrix-keypad
+          - const: gpio-mt-matrix-keypad
+
+  debounce-delay-ms:
+    description: Delay after the first bounce of button.
+    default: 0
+
+  col-scan-delay-us:
+    description: Delay before scanning next active line.
+    default: 0
+
+  number-of-button:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: Number of button connected to the keypad controller.
+
+  linux,no-autorepeat:
+    description: |
+      Disable the Linux input system's autorepeat feature on the input device.
+
+  gpio-activelow:
+    description: Gpio line are active low.
+
+  line-gpios:
+    description: |
+      Gpio lines connected to keypad controller.
+      all gpio line act as row as wel as column lines.
+
+  linux,keymap:
+    $ref: '/schemas/types.yaml#/definitions/uint32-array'
+    description: |
+      An array of packed 1-cell entries containing the equivalent of row,
+      column and linux key-code. The 32-bit big endian cell is packed as:
+          row << 24 | column << 16 | key-code
+
+required:
+  - compatible
+  - number-of-button
+  - line-gpios
+  - linux,keymap
+
+additionalProperties: true
+
+examples:
+  - |
+    mt_matrix_keypad {
+        compatible = "gpio-mt-matrix-keypad";
+        debounce-delay-ms = <10>;
+        col-scan-delay-us = <2>;
+        number-of-button = <7>;
+        linux,no-autorepeat;
+        gpio-activelow;
+        line-gpios = <
+                &gpio1 24 1     /*gpio_56*/
+                &gpio1 23 1     /*gpio_55*/
+                &gpio1 22 1     /*gpio_54*/
+                &gpio1 20 1     /*gpio_52*/
+                &gpio1 16 1     /*gpio_48*/
+        >;
+        linux,keymap = <
+                0x00000000 /* row 0, col 0, KEY_RESERVED/invalid key */
+                0x0001000a /* row 0, col 1, KEY_9 */
+                0x00020003 /* row 0, col 2, KEY_2 */
+                0x00030000 /* row 0, col 3, KEY_RESERVED/invalid key */
+                0x00040002 /* row 0, col 4, KEY_1 */
+                0x0100000a /* row 1, col 0, KEY_9 */
+                0x01010000 /* row 1, col 1, KEY_RESERVED/invalid key */
+                0x01020007 /* row 1, col 2, KEY_6 */
+                0x01030000 /* row 1, col 3, KEY_RESERVED/invalid key */
+                0x01040000 /* row 1, col 4, KEY_RESERVED/invalid key */
+                0x02000003 /* row 2, col 0, KEY_2 */
+                0x02010007 /* row 2, col 1, KEY_6 */
+                0x02020000 /* row 2, col 2, KEY_RESERVED/invalid key */
+                0x02030005 /* row 2, col 3, KEY_4 */
+                0x02040008 /* row 2, col 4, KEY_7 */
+                0x03000000 /* row 3, col 0, KEY_RESERVED/invalid key */
+                0x03010000 /* row 3, col 1, KEY_RESERVED/invalid key */
+                0x03020005 /* row 3, col 2, KEY_4 */
+                0x03030000 /* row 3, col 3, KEY_RESERVED/invalid key */
+                0x03040009 /* row 3, col 4, KEY_8 */
+                0x04000002 /* row 4, col 0, KEY_1 */
+                0x04010000 /* row 4, col 1, KEY_RESERVED/invalid key */
+                0x04020008 /* row 4, col 2, KEY_7 */
+                0x04030009 /* row 4, col 3, KEY_8 */
+                0x04040000 /* row 4, col 4, KEY_RESERVED/invalid key */
+        >;
+    };
-- 
2.20.1