Re: [PATCH v3 1/2] dt-bindings: usb: dwc3: Document Renesas R-Car Gen5 DWC3 xHCI USB controller

[Krzysztof Kozlowski]

On Tue, Aug 11, 2026 at 07:09:33AM +0200, Marek Vasut wrote:
> The Renesas R-Car Gen5 SoC contains multiple instances of DWC3 USB
> controller with glue logic wrapper around them. Document the glue
> logic and DWC3 controller.
> 
> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>
> ---
> Cc: Conor Dooley <conor+dt@xxxxxxxxxx>
> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
> Cc: linux-usb@xxxxxxxxxxxxxxx
> ---
> V2: Rework to use flat bindings for generic plat driver
> V3: - Support one or two PHYs to correctly describe the hardware
>     - Make maximum-speed optional
> ---
>  .../bindings/usb/renesas,rcar-gen5-dwc3.yaml  | 81 +++++++++++++++++++
>  1 file changed, 81 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/renesas,rcar-gen5-dwc3.yaml
> 
> diff --git a/Documentation/devicetree/bindings/usb/renesas,rcar-gen5-dwc3.yaml b/Documentation/devicetree/bindings/usb/renesas,rcar-gen5-dwc3.yaml
> new file mode 100644
> index 0000000000000..37944a7d5be04
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/renesas,rcar-gen5-dwc3.yaml
> @@ -0,0 +1,81 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/usb/renesas,rcar-gen5-dwc3.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas R-Car Gen5 DWC3 xHCI USB controller
> +
> +maintainers:
> +  - Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: renesas,r8a78000-dwc3
> +      - const: renesas,rcar-gen5-dwc3
> +
> +  reg:
> +    maxItems: 2
> +
> +  reg-names:
> +    items:
> +      - const: dwc3
> +      - const: glue
> +
> +  clocks:
> +    maxItems: 1
> +
> +  dr_mode:

We don't accept properties with underscores, unless this is coming from
existing schema but I do not see snps,dwc referenced in the binding.

> +    enum: [ host, otg, peripheral ]
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  maximum-speed:

Again, where is the property defined?

> +    enum: [ super-speed-plus, super-speed, high-speed ]
> +
> +  phys:
> +    minItems: 1
> +    maxItems: 2

Why is this flexible?

> +
> +  phy-names:
> +    minItems: 1
> +    items:
> +      - const: usb2-phy

phy is redundant. Are you implementing completely new bindings which
have nothing in common with all others?

Best regards,
Krzysztof