Re: [PATCH v4 3/4] dt-bindings: Add Qualcomm USB SuperSpeed PHY bindings

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Fri 30 Aug 09:01 PDT 2019, Stephen Boyd wrote:

> Quoting Jorge Ramirez (2019-08-29 00:03:48)
> > On 2/23/19 17:52, Bjorn Andersson wrote:
> > > On Thu 07 Feb 03:17 PST 2019, Jorge Ramirez-Ortiz wrote:
> > >> +
> > >> +Required child nodes:
> > >> +
> > >> +- usb connector node as defined in bindings/connector/usb-connector.txt
> > >> +  containing the property vbus-supply.
> > >> +
> > >> +Example:
> > >> +
> > >> +usb3_phy: usb3-phy@78000 {
> > >> +    compatible = "qcom,snps-usb-ssphy";
> > >> +    reg = <0x78000 0x400>;
> > >> +    #phy-cells = <0>;
> > >> +    clocks = <&rpmcc RPM_SMD_LN_BB_CLK>,
> > >> +             <&gcc GCC_USB_HS_PHY_CFG_AHB_CLK>,
> > >> +             <&gcc GCC_USB3_PHY_PIPE_CLK>;
> > >> +    clock-names = "ref", "phy", "pipe";
> > >> +    resets = <&gcc GCC_USB3_PHY_BCR>,
> > >> +             <&gcc GCC_USB3PHY_PHY_BCR>;
> > >> +    reset-names = "com", "phy";
> > >> +    vdd-supply = <&vreg_l3_1p05>;
> > >> +    vdda1p8-supply = <&vreg_l5_1p8>;
> > >> +    usb3_c_connector: usb3-c-connector {
> 
> Node name should be 'connector', not usb3-c-connector.
> 

It probably has to be usb-c-connector, because we have a
micro-usb-connector on the same board.

> > > 
> > > The USB-C connector is attached both to the HS and SS PHYs, so I think
> > > you should represent this external to this node and use of_graph to
> > > query it.
> > 
> > but AFAICS we wont be able to retrieve the vbux-supply from an external
> > node (that interface does not exist).
> > 
> > rob, do you have a suggestion?
> 
> Shouldn't the vbus supply be in the phy? Or is this a situation where
> the phy itself doesn't have the vbus supply going to it because the PMIC
> gets in the way and handles the vbus for the connector by having the SoC
> communicate with the PMIC about when to turn the vbus on and off, etc?
> 

That's correct, the VBUS comes out of the PMIC and goes directly to the
connector.

The additional complicating factor here is that the connector is wired
to a USB2 phy as well, so we need to wire up detection and vbus control
to both of them - but I think this will be fine, if we can only figure
out a sane way of getting hold of the vbus-supply.

Regards,
Bjorn