Re: [PATCH v7 1/2] dt-bindings: phy: Add CIX Sky1 USB3 PHY

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] dt-bindings: phy: cix,sky1-usb3-phy uses #phy-cells = 0 for
  two-lane PHY
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commit 2ddbb23ac4fa77b6667ad1996ba778aaeb0d7a6c
Author: Hongliang Yang <hongliang.yang@cixtech.com>

dt-bindings: phy: Add CIX Sky1 USB3 PHY

This commit adds the Device Tree binding schema for the CIX Sky1 USB3
SuperSpeed PHY.

> diff --git a/Documentation/devicetree/bindings/phy/cix,sky1-usb3-phy.yaml b/Documentation/devicetree/bindings/phy/cix,sky1-usb3-phy.yaml
> new file mode 100644
> index 0000000000000..205140bf84e7c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/cix,sky1-usb3-phy.yaml
> @@ -0,0 +1,78 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/cix,sky1-usb3-phy.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: CIX Sky1 USB3 PHY
> +
> +maintainers:
> +  - Hongliang Yang <hongliang.yang@cixtech.com>
> +
> +description: |
> +  The CIX Sky1 USB3 PHY provides the SuperSpeed lanes of the USB3 Type-A
> +  ports of the SoC.
> +
> +  Both lanes are programmed through one register block and share the
> +  same clocks and resets, so the node is a single PHY provider with
> +  #phy-cells = <0> that all consumers reference. The driver reference
> +  counts phy_init() and phy_exit(), so the block is set up once for all
> +  its consumers.
> +
> +properties:
> +  compatible:
> +    const: cix,sky1-usb3-phy
> +
> +  reg:
> +    maxItems: 1
> +
> +  "#phy-cells":
> +    const: 0

[Severity: Low]
As reported by Krzysztof Kozlowski on v6 [1], should #phy-cells be 1 so
that each USB3 controller consumer node can specify which of the two PHY
lanes it is wired to?

The hardware block contains two independent SuperSpeed lanes with separate
per-lane register sets and lane-disable controls serving two distinct USB3
controllers. Constraining #phy-cells to 0 omits which controller connects
to which lane from the Device Tree ABI, preventing per-lane control,
power management, or tuning without breaking the binding.

In addition, the description justifies #phy-cells = <0> by citing Linux
driver reference counting of phy_init() and phy_exit(), whereas bindings
should describe the hardware rather than driver implementation details.

[1] https://lore.kernel.org/r/20261105-kind-macaque-of-enhancement-ee0365@quoll

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Sashiko AI review · https://sashiko.dev/#/patchset/20261111030937.2954646-1-hongliang.yang@cixtech.com?part=1

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