dt-bindings: usb: dwc3: Add Realtek DHC RTD SoC DWC3 USB

Document the DWC3 USB bindings for Realtek SoCs.
Signed-off-by: Stanley Chang <stanley_chang@realtek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230826031028.1892-2-stanley_chang@realtek.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/realtek,rtd-dwc3.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Realtek Semiconductor Corporation
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/realtek,rtd-dwc3.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek DWC3 USB SoC Controller Glue
+
+maintainers:
+  - Stanley Chang <stanley_chang@realtek.com>
+
+description:
+  The Realtek DHC SoC embeds a DWC3 USB IP Core configured for USB 2.0
+  and USB 3.0 in host or dual-role mode.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - realtek,rtd1295-dwc3
+          - realtek,rtd1315e-dwc3
+          - realtek,rtd1319-dwc3
+          - realtek,rtd1319d-dwc3
+          - realtek,rtd1395-dwc3
+          - realtek,rtd1619-dwc3
+          - realtek,rtd1619b-dwc3
+      - const: realtek,rtd-dwc3
+
+  reg:
+    items:
+      - description: Address and length of register set for wrapper of dwc3 core.
+      - description: Address and length of register set for pm control.
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 1
+
+  ranges: true
+
+patternProperties:
+  "^usb@[0-9a-f]+$":
+    $ref: snps,dwc3.yaml#
+    description: Required child node
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+  - ranges
+
+additionalProperties: false
+
+examples:
+  - |
+    usb@98013e00 {
+        compatible = "realtek,rtd1319d-dwc3", "realtek,rtd-dwc3";
+        reg = <0x98013e00 0x140>, <0x98013f60 0x4>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges;
+
+        usb@98050000 {
+            compatible = "snps,dwc3";
+            reg = <0x98050000 0x9000>;
+            interrupts = <0 94 4>;
+            phys = <&usb2phy &usb3phy>;
+            phy-names = "usb2-phy", "usb3-phy";
+            dr_mode = "otg";
+            usb-role-switch;
+            role-switch-default-mode = "host";
+            snps,dis_u2_susphy_quirk;
+            snps,parkmode-disable-ss-quirk;
+            snps,parkmode-disable-hs-quirk;
+            maximum-speed = "high-speed";
+        };
+    };