dt-bindings: usb: Add Socionext Uniphier DWC3 controller

The Socionext Uniphier DWC3 controller binding is already in use, but
undocumented. It's a straight-forward binding similar to other DWC3
bindings.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://patch.msgid.link/20260105162418.2842825-1-robh@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/socionext,uniphier-dwc3.yaml

@@ -0,0 +1,89 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/socionext,uniphier-dwc3.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Socionext Uniphier SuperSpeed DWC3 USB SoC controller
+
+maintainers:
+  - Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
+  - Masami Hiramatsu <mhiramat@kernel.org>
+
+select:
+  properties:
+    compatible:
+      contains:
+        const: socionext,uniphier-dwc3
+  required:
+    - compatible
+
+properties:
+  compatible:
+    items:
+      - const: socionext,uniphier-dwc3
+      - const: snps,dwc3
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    minItems: 1
+    items:
+      - description: Host or single combined interrupt
+      - description: Peripheral interrupt
+
+  interrupt-names:
+    minItems: 1
+    items:
+      - enum:
+          - dwc_usb3
+          - host
+      - const: peripheral
+
+  clocks:
+    maxItems: 3
+
+  clock-names:
+    items:
+      - const: ref
+      - const: bus_early
+      - const: suspend
+
+  phys:
+    description: 1 to 4 HighSpeed PHYs followed by 1 or 2 SuperSpeed PHYs
+    minItems: 1
+    maxItems: 6
+
+  resets:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - phys
+
+unevaluatedProperties: false
+
+allOf:
+  - $ref: snps,dwc3.yaml#
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    usb@65a00000 {
+        compatible = "socionext,uniphier-dwc3", "snps,dwc3";
+        reg = <0x65a00000 0xcd00>;
+        interrupt-names = "dwc_usb3";
+        interrupts = <GIC_SPI 134 IRQ_TYPE_LEVEL_HIGH>;
+        clock-names = "ref", "bus_early", "suspend";
+        clocks = <&sys_clk 12>, <&sys_clk 12>, <&sys_clk 12>;
+        resets = <&usb0_rst 15>;
+        phys = <&usb0_hsphy0>, <&usb0_hsphy1>,
+               <&usb0_ssphy0>, <&usb0_ssphy1>;
+        dr_mode = "host";
+    };