Re: [RFC 1/3] dt-bindings: usb: qcom,dwc3: Add support for multiple power-domains

From: Krzysztof Kozlowski
Date: Tue Mar 05 2024 - 12:08:02 EST


On 05/03/2024 17:57, Sriram Dash wrote:
> Some target systems allow multiple resources to be managed by firmware.
> On these targets, tasks related to clocks, regulators, resets, and
> interconnects can be delegated to the firmware, while the remaining
> responsibilities are handled by Linux.
>
> To support the management of partial resources in Linux and leave the rest
> to firmware, multiple power domains are introduced. Each power domain can
> manage one or more resources, depending on the specific use case.
>
> These power domains handle SCMI calls to the firmware, enabling the
> activation and deactivation of firmware-managed resources.
>
> Signed-off-by: Sriram Dash <quic_sriramd@xxxxxxxxxxx>
> ---
> .../phy/qcom,sc8280xp-qmp-usb3-uni-phy.yaml | 74 ++++++++++++++++------
> .../bindings/phy/qcom,usb-snps-femto-v2.yaml | 49 ++++++++++++--
> .../devicetree/bindings/usb/qcom,dwc3.yaml | 37 ++++++++++-
> 3 files changed, 130 insertions(+), 30 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb3-uni-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb3-uni-phy.yaml
> index 1e2d4dd..53b9ba9 100644
> --- a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb3-uni-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb3-uni-phy.yaml
> @@ -44,7 +44,32 @@ properties:
> maxItems: 5
>
> power-domains:
> - maxItems: 1
> + description: specifies a phandle to PM domain provider node

Please drop all redundant descriptions. Adding them is not even related
to this patch.

> + minItems: 1
> + maxItems: 2
> +
> + power-domain-names:
> + description:
> + A list of power domain name strings sorted in the same order as the
> + power-domains property.
> +
> + For platforms where some resource are firmware managed, the name
> + corresponding to the index of an SCMI domain provider can be
> + "usb_core" or "usb_transfer".
> + items:
> + - const: usb_core
> + - const: usb_transfer

How is this related to fw-managed? I fail to see it. Don't mix
independent problems in one patch.

> +
> + qmp,fw-managed:

Please do not upstream vendor code directly, but perform basic
adjustment to upstream Linux kernel. There is no such company as gmp.

Run this first through your internal review process.

> + description:
> + Some targets allow multiple resources to be managed by firmware.

You miss clear mapping between compatibles and this property - allOf
restricting it to specific SoCs.

Is this different property than qcom,controlled-remotely?

Best regards,
Krzysztof