RE: [PATCH v3 4/5] dt-bindings: phy: realtek: Add the doc about the Realtek SoC USB 2.0 PHY

[Stanley Chang[昌育德]]

> > Maybe I use the word "control power domain" is not well, I just want to
> control the ldo of usb phy.
> > Revised:
> > The phandle of syscon used to control the ldo of USB PHY.
> 
> Isn't this still a power domain?

I only control a register, it is not needed a driver of power domain.


> >
> >>> +
> >>> +patternProperties:
> >>> +  "^phy@[0-3]+$":
> >>> +    type: object
> >>> +    description:
> >>> +      Each sub-node is a PHY device for one XHCI controller.
> >>
> >> I don't think it is true. You claim above that you have 0 as
> >> phy-cells, means you have one phy. Here you say you can have up to 4 phys.
> >
> > I mean the driver can support up to 4 phys.
> 
> What driver can or cannot do, does not matter. This is about hardware.
> 
> > For RTD1295 has only one phy.
> > For RTD1395 has two phys.
> 
> Two phys? So how do you reference them when cells=0?


About RTD1395 SoCs USB
  XHCI controller#1 -- usb2phy -- phy#0
                          |- phy#1
One xhci controller map to one phy driver.
And one phy driver have two phys (phy@0 and phy@1).

Maybe the "phy" name is confusing.
This "phy" not mean a phy driver.
Would "port" be more appropriate? 

For example,
Using phy@0 and phy@1:
    usb_port1_usb2phy: usb-phy@13c14 {
        compatible = "realtek,rtd1395-usb2phy", "realtek,usb2phy";
        reg = <0x132c4 0x4>, <0x31280 0x8>;
        #address-cells = <1>;
        #size-cells = <0>;
        #phy-cells = <0>;
        realtek,usb-ctrl = <&usb_ctrl>;

        phy@0 {
            reg = <0>;
        };
        phy@1 {
            reg = <1>;
        };
    };

Change: port@0 and port@1
    usb_port1_usb2phy: usb-phy@13c14 {
        compatible = "realtek,rtd1395-usb2phy", "realtek,usb2phy";
        reg = <0x132c4 0x4>, <0x31280 0x8>;
        #address-cells = <1>;
        #size-cells = <0>;
        #phy-cells = <0>;
        realtek,usb-ctrl = <&usb_ctrl>;

        prot@0 {
            reg = <0>;
        };
        port@1 {
            reg = <1>;
        };
    };