[PATCH v2 1/4] dt-bindings: usb: dwc3: Add Google Tensor G5 DWC3

[Roy Luo]

On Thu, Oct 9, 2025 at 12:26 AM Krzysztof Kozlowski <krzk at kernel.org> wrote:
>
> On 09/10/2025 14:12, Roy Luo wrote:
> > On Wed, Oct 8, 2025 at 4:56 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
> >>
> >> On 08/10/2025 14:59, Roy Luo wrote:
> >>> Document the device tree bindings for the DWC3 USB controller found in
> >>> Google Tensor SoCs, starting with the G5 generation.
> >>>
> >>> The Tensor G5 silicon represents a complete architectural departure from
> >>
> >>
> >> G5 does not have a model number like G1-G4?
> >
> > There's no model number for G5, I'm sticking to the existing "gs" prefix
> > as they're still in the same SoC family.  Please let me know if you have any
> > concerns.
> >
> >>
> >>> previous generations (like gs101), including entirely new clock/reset
> >>> schemes, top-level wrapper and register interface. Consequently,
> >>> existing Samsung/Exynos DWC3 USB bindings and drivers are incompatible,
> >>
> >> Do not reference drivers. Explain the hardware.
> >
> > Ack, all mentions of "driver" will be removed in the next patch.
> >
> >>
> >>> necessitating this new device tree binding.
> >>>
> >>> The USB controller on Tensor G5 is based on Synopsys DWC3 IP and features
> >>> Dual-Role Device single port with hibernation support.
> >>>
> >>> Signed-off-by: Roy Luo <royluo at google.com>
> >>> ---
> >>>  .../bindings/usb/google,gs-dwc3.yaml          | 145 ++++++++++++++++++
> >>>  1 file changed, 145 insertions(+)
> >>>  create mode 100644 Documentation/devicetree/bindings/usb/google,gs-dwc3.yaml
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/usb/google,gs-dwc3.yaml b/Documentation/devicetree/bindings/usb/google,gs-dwc3.yaml
> >>> new file mode 100644
> >>> index 000000000000..9eb0bf726e8d
> >>> --- /dev/null
> >>> +++ b/Documentation/devicetree/bindings/usb/google,gs-dwc3.yaml
> >>> @@ -0,0 +1,145 @@
> >>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> >>> +# Copyright (c) 2025, Google LLC
> >>> +%YAML 1.2
> >>> +---
> >>> +$id: http://devicetree.org/schemas/usb/google,gs-dwc3.yaml#
> >>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> >>> +
> >>> +title: Google Tensor Series (G5+) DWC3 USB SoC Controller
> >>> +
> >>> +maintainers:
> >>> +  - Roy Luo <royluo at google.com>
> >>> +
> >>> +description: |
> >>
> >>
> >> Do not need '|' unless you need to preserve formatting.
> >
> > Ack, will fix this in the next patch.
> >
> >>
> >>> +  Describes the DWC3 USB controller block implemented on Google Tensor SoCs,
> >>> +  starting with the G5 generation. Based on Synopsys DWC3 IP, the controller
> >>> +  features Dual-Role Device single port with hibernation add-on.
> >>> +
> >>> +properties:
> >>> +  compatible:
> >>> +    items:
> >>> +      - enum:
> >>> +          - google,gs5-dwc3
> >>> +
> >>> +  reg:
> >>> +    minItems: 3
> >>
> >> Drop
> >>
> >>> +    maxItems: 3
> >>> +
> >>> +  reg-names:
> >>> +    description: |
> >>> +      The following memory regions must present:
> >>> +        - dwc3_core: Core DWC3 IP registers.
> >>> +        - host_cfg_csr: Hibernation control registers.
> >>> +        - usbint_csr: Hibernation interrupt registers.
> >>
> >> Drop description or move it to items in reg. See other bindings.
> >
> > Ack, will use an item list in reg instead.
> >
> >>
> >>> +    items:
> >>> +      - const: dwc3_core
> >>> +      - const: host_cfg_csr
> >>> +      - const: usbint_csr
> >>> +
> >>> +  interrupts:
> >>> +    minItems: 3
> >>
> >> Drop
> >
> > Ack, will use an item list instead.
> >
> >>
> >>> +    maxItems: 3
> >>> +
> >>> +  interrupt-names:
> >>> +    description: |
> >>> +      The following interrupts must present:
> >>> +        - dwc_usb3: Core DWC3 interrupt.
> >>> +        - hs_pme_irq: High speed remote wakeup interrupt for hibernation.
> >>> +        - ss_pme_irq: Super speed remote wakeup interrupt for hibernation.
> >>
> >> From where did you get this style? Don't write bindings with chat gpt or
> >> whatever other tool. it is a waste of our time.
> >
> > I referenced the style from a recent dt binding change [1] that adds
> > "Documentation/devicetree/bindings/usb/qcom,snps-dwc3.yaml".
> > I thought it would be a good reference because it's relatively new
> > and is also a binding for SNPS dwc3 glue logic. Perhaps that style
> > doesn't apply here because qcom,snps-dwc3.yaml supports
> > multiple compatible and here we have only one?
> >
> > Just to clarify, I'm a Gemini user and this patch is 100% organic,
> > hand-crafted by a living human brain :)
> >
> > [1] https://lore.kernel.org/all/20250414-dwc3-refactor-v7-2-f015b358722d@oss.qualcomm.com/
>
> Your code is not at all like above, you do not have any variants here,
> so you cannot use that syntax - is not correct here.
>
> Best regards,
> Krzysztof

Thanks for the clarification.

Regards,
Roy Luo