Re: [PATCH v2 3/7] dt-bindings: usb: Add qcom,sa8255p-dwc3 for firmware-managed resources

[Krzysztof Kozlowski]

On Thu, Sep 03, 2026 at 09:08:23PM +0530, Faisal Hassan wrote:
> On Qualcomm automotive SoC sa8255p, platform resources like clocks,
> interconnects, resets, regulators and GDSC are abstracted and managed
> collectively by firmware.
> 
> Add a new binding file for firmware-managed USB controllers where
> access to these resources is exposed as two power domains:
> - Power domain: Controls power supply (GDSC) to the USB controller
> - Bus domain: Controls clocks and interconnects for data transfer
> 
> The binding makes power-domains and power-domain-names properties mandatory
> for firmware-managed platforms, while excluding the clocks property since
> clocks are managed through the power domains.
> 
> Co-developed-by: Sriram Dash <sriram.dash@xxxxxxxxxxxxxxxx>
> Signed-off-by: Sriram Dash <sriram.dash@xxxxxxxxxxxxxxxx>
> Signed-off-by: Faisal Hassan <faisal.hassan@xxxxxxxxxxxxxxxx>
> ---
>  .../bindings/usb/qcom,sa8255p-dwc3.yaml       | 123 ++++++++++++++++++
>  1 file changed, 123 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/qcom,sa8255p-dwc3.yaml
> 
> diff --git a/Documentation/devicetree/bindings/usb/qcom,sa8255p-dwc3.yaml b/Documentation/devicetree/bindings/usb/qcom,sa8255p-dwc3.yaml
> new file mode 100644
> index 000000000000..c6db7bcf4981
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/qcom,sa8255p-dwc3.yaml
> @@ -0,0 +1,123 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/usb/qcom,sa8255p-dwc3.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm SA8255P USB3 Controller with Firmware-Managed Resources
> +
> +maintainers:
> +  - Wesley Cheng <wesley.cheng@xxxxxxxxxxxxxxxx>
> +  - Faisal Hassan <faisal.hassan@xxxxxxxxxxxxxxxx>
> +
> +description:
> +  USB controller on Qualcomm SA8255P automotive SoC where platform resources
> +  such as clocks, interconnects, resets, regulators and the GDSC are
> +  abstracted and managed collectively by firmware through SCMI (System
> +  Control and Management Interface).
> +
> +  Access to these firmware-managed resources is exposed as two power
> +  domains, one gating the power supply (GDSC) to the controller, and one
> +  gating the clocks and interconnects used for data transfer.
> +
> +properties:
> +  compatible:
> +    const: qcom,sa8255p-dwc3
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    minItems: 1
> +    maxItems: 6

Why is this flexible?

> +
> +  interrupt-names:
> +    minItems: 1
> +    maxItems: 6

Why is this flexible even more, allowing completely random names?

> +
> +  power-domains:
> +    description: |
> +      Power domains are provided by SCMI (System Control and Management
> +      Interface). See Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> +      for details.
> +
> +      Exactly two power domains must be specified:
> +        - "power": controls power supply (GDSC) to the USB controller
> +        - "bus": controls clocks and interconnects used for data transfer

Look at other bindings how they do it.

I finished here, because you would avoid all above questions if you just
copied recently added or reviewed on the list SA8xxx binding. You did
not, so basically I expect more of unexpected code, which is pointless
to review. Just open existing files...

Best regards,
Krzysztof