dt-bindings: pinctrl: Document nuvoton ma35d1 pin control

Add documentation to describe nuvoton ma35d1 pin control and GPIO.

Signed-off-by: Jacky Huang <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

Documentation/devicetree/bindings/pinctrl/nuvoton,ma35d1-pinctrl.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/nuvoton,ma35d1-pinctrl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Nuvoton MA35D1 pin control and GPIO
+
+maintainers:
+  - Shan-Chun Hung <[e-mail]>
+  - Jacky Huang <[e-mail]>
+
+allOf:
+  - $ref: pinctrl.yaml#
+
+properties:
+  compatible:
+    enum:
+      - nuvoton,ma35d1-pinctrl
+
+  reg:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 1
+
+  nuvoton,sys:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      phandle of the system-management node.
+
+  ranges: true
+
+patternProperties:
+  "^gpio@[0-9a-f]+$":
+    type: object
+    properties:
+      gpio-controller: true
+
+      '#gpio-cells':
+        const: 2
+
+      reg:
+        maxItems: 1
+
+      clocks:
+        maxItems: 1
+
+      interrupt-controller: true
+
+      '#interrupt-cells':
+        const: 2
+
+      interrupts:
+        description:
+          The interrupt outputs to sysirq.
+        maxItems: 1
+
+    required:
+      - gpio-controller
+      - '#gpio-cells'
+      - reg
+      - clocks
+      - interrupt-controller
+      - '#interrupt-cells'
+      - interrupts
+
+    additionalProperties: false
+
+  "-grp$":
+    type: object
+    description:
+      Pinctrl node's client devices use subnodes for desired pin configuration.
+      Client device subnodes use below standard properties.
+    patternProperties:
+      "-pins$":
+        type: object
+        description:
+          A pinctrl node should contain at least one subnodes representing the
+          pinctrl groups available on the machine. Each subnode will list the
+          pins it needs, and how they should be configured, with regard to muxer
+          configuration, pullups, drive strength, input enable/disable and input
+          schmitt.
+        $ref: /schemas/pinctrl/pincfg-node.yaml
+
+        properties:
+          nuvoton,pins:
+            description:
+              Each entry consists of 4 parameters and represents the mux and config
+              setting for one pin.
+            $ref: /schemas/types.yaml#/definitions/uint32-matrix
+            minItems: 1
+            items:
+              items:
+                - minimum: 0
+                  maximum: 13
+                  description:
+                    Pin bank.
+                - minimum: 0
+                  maximum: 15
+                  description:
+                    Pin bank index.
+                - minimum: 0
+                  maximum: 15
+                  description:
+                    Mux 0 means GPIO and mux 1 to 15 means the specific device function.
+
+          power-source:
+            description: |
+              Valid arguments are described as below:
+              0: power supply of 1.8V
+              1: power supply of 3.3V
+            enum: [0, 1]
+
+          drive-strength-microamp:
+            oneOf:
+              - enum: [ 2900, 4400, 5800, 7300, 8600, 10100, 11500, 13000 ]
+                description: 1.8V I/O driving strength
+              - enum: [ 17100, 25600, 34100, 42800, 48000, 56000, 77000, 82000 ]
+                description: 3.3V I/O driving strength
+
+          bias-disable: true
+
+          bias-pull-up: true
+
+          bias-pull-down: true
+
+          input-schmitt-disable: true
+
+        additionalProperties: false
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - nuvoton,sys
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/clock/nuvoton,ma35d1-clk.h>
+
+    pinctrl@40040000 {
+        compatible = "nuvoton,ma35d1-pinctrl";
+        reg = <0x40040000 0xc00>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        nuvoton,sys = <&sys>;
+        ranges = <0x0 0x40040000 0x400>;
+
+        gpio@0 {
+            reg = <0x0 0x40>;
+            interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+            clocks = <&clk GPA_GATE>;
+            gpio-controller;
+            #gpio-cells = <2>;
+            interrupt-controller;
+            #interrupt-cells = <2>;
+        };
+
+        uart-grp {
+            uart11-pins {
+                nuvoton,pins = <11 0 2>,
+                               <11 1 2>,
+                               <11 2 2>,
+                               <11 3 2>;
+                power-source = <1>;
+                bias-disable;
+            };
+        };
+    };