dt-bindings: usb: dwc3: Add the Amlogic A1 Family DWC3 Glue Bindings

The Amlogic A1 SoC Family embeds 1 USB Controllers:
 - a DWC3 IP configured as Host for USB2 and USB3

A glue connects the controllers to the USB2 PHY of A1 SoC.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Yue Wang <yue.wang@amlogic.com>
Signed-off-by: Hanjie Lin <hanjie.lin@amlogic.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

Documentation/devicetree/bindings/usb/amlogic,meson-g12a-usb-ctrl.yaml

@@ -22,10 +22,14 @@ description: |
   The DWC3 Glue controls the PHY routing and power, an interrupt line is
   connected to the Glue to serve as OTG ID change detection.
 
+  The Amlogic A1 embeds a DWC3 USB IP Core configured for USB2 in
+  host-only mode.
+
 properties:
   compatible:
     enum:
       - amlogic,meson-g12a-usb-ctrl
+      - amlogic,meson-a1-usb-ctrl
 
   ranges: true
 
@@ -84,6 +88,25 @@ required:
   - phys
   - dr_mode
 
+allOf:
+  - if:
+      properties:
+        compatible:
+          enum:
+            - amlogic,meson-a1-usb-ctrl
+
+    then:
+      properties:
+        clocks:
+          minItems: 3
+        clock-names:
+          items:
+            - const: usb_ctrl
+            - const: usb_bus
+            - const: xtal_usb_ctrl
+      required:
+        - clock-names
+
 examples:
   - |
     usb: usb@ffe09000 {