[PATCH 1/4] dt-bindings: usb: generic-ehci: Allow describing the root hub ports

[Chen-Yu Tsai]

On Tue, Nov 10, 2026 at 4:20 PM Arun Iyengar via B4 Relay
<devnull+aiyengar1990.gmail.com at kernel.org> wrote:
>
> From: Arun Iyengar <aiyengar1990 at gmail.com>
>
> The USB 2.0 lines and the SuperSpeed lanes of a USB 3 connector don't
> always reach the same host controller. On the Rockchip RK3588, the
> SuperSpeed-only USB 3.0 host 2 (xHCI) is paired on the board with one
> of the separate USB 2.0 hosts (EHCI/OHCI). Only the device tree knows
> which EHCI root hub port shares a connector with which SuperSpeed port.
>
> The USB core already reads a hub's OF graph, with one graph port per
> downstream port, and uses it for the port connect type. Allow the same
> "ports" node on EHCI controllers, so that a root hub port can be linked
> to its usb-connector node.
>
> Signed-off-by: Arun Iyengar <aiyengar1990 at gmail.com>
> ---
>  Documentation/devicetree/bindings/usb/generic-ehci.yaml | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/usb/generic-ehci.yaml b/Documentation/devicetree/bindings/usb/generic-ehci.yaml
> index 908b02d9175e..9dcba539d60d 100644
> --- a/Documentation/devicetree/bindings/usb/generic-ehci.yaml
> +++ b/Documentation/devicetree/bindings/usb/generic-ehci.yaml
> @@ -160,6 +160,19 @@ properties:
>        - host
>        - otg
>
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +    description:
> +      The root hub's downstream facing ports, linked to the connectors they
> +      are wired to. Needed when a connector's SuperSpeed lanes go to a
> +      different host controller, which then pairs with the root hub port
> +      through the connector.
> +
> +    patternProperties:
> +      "^port@[1-9a-f][0-9a-f]*$":
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description: Root hub port, numbered from 1.
> +

Would this patch covering all HCDs be better?

https://lore.kernel.org/all/20261014082037.1774672-2-wenst@chromium.org/

Also see Rob's comment about covering the port numbers.

ChenYu

>  required:
>    - compatible
>    - reg
>
> --
> 2.55.0
>
>
>