dt-bindings: mt7621-gpio: convert bindings to YAML format

Convert the mt7621-gpio device tree bindings to the new YAML format.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201207081151.7489-1-sergio.paracuellos@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.txt

-Mediatek MT7621 SoC GPIO controller bindings
-
-The IP core used inside these SoCs has 3 banks of 32 GPIOs each.
-The registers of all the banks are interwoven inside one single IO range.
-We load one GPIO controller instance per bank. Also the GPIO controller can receive
-interrupts on any of the GPIOs, either edge or level. It then interrupts the CPU
-using GIC INT12.
-
-Required properties for the top level node:
-- #gpio-cells : Should be two. The first cell is the GPIO pin number and the
-   second cell specifies GPIO flags, as defined in <dt-bindings/gpio/gpio.h>.
-   Only the GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
-- #interrupt-cells : Specifies the number of cells needed to encode an
-   interrupt. Should be 2. The first cell defines the interrupt number,
-   the second encodes the trigger flags encoded as described in
-   Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
-- compatible:
-  - "mediatek,mt7621-gpio" for Mediatek controllers
-- reg : Physical base address and length of the controller's registers
-- interrupt-parent : phandle of the parent interrupt controller.
-- interrupts : Interrupt specifier for the controllers interrupt.
-- interrupt-controller : Mark the device node as an interrupt controller.
-- gpio-controller : Marks the device node as a GPIO controller.
-
-Example:
-	gpio@600 {
-		#gpio-cells = <2>;
-		#interrupt-cells = <2>;
-		compatible = "mediatek,mt7621-gpio";
-		gpio-controller;
-		interrupt-controller;
-		reg = <0x600 0x100>;
-		interrupt-parent = <&gic>;
-		interrupts = <GIC_SHARED 12 IRQ_TYPE_LEVEL_HIGH>;
-	};

Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/mediatek,mt7621-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Mediatek MT7621 SoC GPIO controller
+
+maintainers:
+  - Sergio Paracuellos <sergio.paracuellos@gmail.com>
+
+description: |
+  The IP core used inside these SoCs has 3 banks of 32 GPIOs each.
+  The registers of all the banks are interwoven inside one single IO range.
+  We load one GPIO controller instance per bank. Also the GPIO controller can receive
+  interrupts on any of the GPIOs, either edge or level. It then interrupts the CPU
+  using GIC INT12.
+
+properties:
+  $nodename:
+    pattern: "^gpio@[0-9a-f]+$"
+
+  compatible:
+    const: mediatek,mt7621-gpio
+
+  reg:
+    maxItems: 1
+
+  "#gpio-cells":
+    const: 2
+
+  gpio-controller: true
+  gpio-ranges: true
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 2
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - "#gpio-cells"
+  - gpio-controller
+  - gpio-ranges
+  - interrupt-controller
+  - "#interrupt-cells"
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/mips-gic.h>
+
+    gpio@600 {
+      compatible = "mediatek,mt7621-gpio";
+      reg = <0x600 0x100>;
+      #gpio-cells = <2>;
+      gpio-controller;
+      gpio-ranges = <&pinctrl 0 0 95>;
+      interrupt-controller;
+      #interrupt-cells = <2>;
+      interrupt-parent = <&gic>;
+      interrupts = <GIC_SHARED 12 IRQ_TYPE_LEVEL_HIGH>;
+    };
+
+...