dt-bindings: net: orion-mdio: Convert to JSON schema

Convert the marvell,orion-mdio binding to JSON schema.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20220505210621.3637268-1-chris.packham@alliedtelesis.co.nz
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/devicetree/bindings/net/marvell,orion-mdio.yaml

@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/marvell,orion-mdio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Marvell MDIO Ethernet Controller interface
+
+maintainers:
+  - Andrew Lunn <andrew@lunn.ch>
+
+description: |
+  The Ethernet controllers of the Marvel Kirkwood, Dove, Orion5x, MV78xx0,
+  Armada 370, Armada XP, Armada 7k and Armada 8k have an identical unit that
+  provides an interface with the MDIO bus. Additionally, Armada 7k and Armada
+  8k has a second unit which provides an interface with the xMDIO bus. This
+  driver handles these interfaces.
+
+allOf:
+  - $ref: "mdio.yaml#"
+
+properties:
+  compatible:
+    enum:
+      - marvell,orion-mdio
+      - marvell,xmdio
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    minItems: 1
+    maxItems: 4
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: true
+
+examples:
+  - |
+    mdio@d0072004 {
+      compatible = "marvell,orion-mdio";
+      reg = <0xd0072004 0x4>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+      interrupts = <30>;
+
+      phy0: ethernet-phy@0 {
+        reg = <0>;
+      };
+
+      phy1: ethernet-phy@1 {
+        reg = <1>;
+      };
+    };