dt-bindings: phy: renesas: Document Renesas RZ/G3E USB3.0 PHY

Document Renesas RZ/G3E USB3.0 PHY. This IP is connected between
USB3HOST and PHY module. The main functions of the module are
as follows:
 - Reset control
 - Control of PHY input pins
 - Monitoring of PHY output pins

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20251029084037.108610-2-biju.das.jz@bp.renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/phy/renesas,rzg3e-usb3-phy.yaml

@@ -0,0 +1,63 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/renesas,rzg3e-usb3-phy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas RZ/G3E USB 3.0 PHY
+
+maintainers:
+  - Biju Das <biju.das.jz@bp.renesas.com>
+
+properties:
+  compatible:
+    const: renesas,r9a09g047-usb3-phy
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: APB bus clock
+      - description: USB 2.0 PHY reference clock
+      - description: USB 3.0 PHY reference clock
+
+  clock-names:
+    items:
+      - const: pclk
+      - const: core
+      - const: ref_alt_clk_p
+
+  power-domains:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  '#phy-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - power-domains
+  - resets
+  - '#phy-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/renesas,r9a09g047-cpg.h>
+
+    usb-phy@15870000 {
+        compatible = "renesas,r9a09g047-usb3-phy";
+        reg = <0x15870000 0x10000>;
+        clocks = <&cpg CPG_MOD 0xb0>, <&cpg CPG_CORE 13>, <&cpg CPG_CORE 12>;
+        clock-names = "pclk", "core", "ref_alt_clk_p";
+        power-domains = <&cpg>;
+        resets = <&cpg 0xaa>;
+        #phy-cells = <0>;
+    };