dt-bindings: usb: usb251xb: support usage case without I2C control

Currently, the usb251xb assumes i2c control, but from HW point of
view, the hub supports usage case without any i2c control, I.E we
only want the gpio controls, for example the following dt node:

usb-hub {
	compatible = "microchip,usb2512b";
	reset-gpios = <&porta 8 GPIO_ACTIVE_LOW>;
};

Modify the dt-binding of usb2512b to support this usage case, and add
the usage example to the examples section.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250825234509.1041-2-jszhang@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/usb/usb251xb.yaml b/Documentation/devicetree/bindings/usb/usb251xb.yaml
index ac5b99710332a7c263d7583b4749b03405ed52a8..0329a6aaaa928e625ebc2de4541d440c6e233466 100644 (file)
--- a/Documentation/devicetree/bindings/usb/usb251xb.yaml
+++ b/Documentation/devicetree/bindings/usb/usb251xb.yaml
@@ -240,7 +240,6 @@ additionalProperties: false
 
 required:
   - compatible
-  - reg
 
 examples:
   - |
@@ -269,3 +268,11 @@ examples:
         swap-dx-lanes = <1 2>;
       };
     };
+
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    usb-hub {
+      /* I2C is not connected */
+      compatible = "microchip,usb2512b";
+      reset-gpios = <&porta 8 GPIO_ACTIVE_LOW>;
+    };