Re: [PATCH 4/5] dt-bindings: usb: dwc3: of-simple: add compatible for HiSi

From: John Stultz
Date: Wed Oct 02 2019 - 16:45:36 EST


On Wed, Sep 25, 2019 at 11:42 PM Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote:
> On Wed, 2019-09-25 at 21:06 -0700, John Stultz wrote:
> > On Wed, Sep 25, 2019 at 6:34 PM Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote:
> > > On Wed, 2019-09-25 at 23:42 +0000, John Stultz wrote:
> > > > +++ b/Documentation/devicetree/bindings/usb/hisi,dwc3.txt
> > > > @@ -0,0 +1,52 @@
> > > > +HiSi SuperSpeed DWC3 USB SoC controller
> > > > +
> > > > +Required properties:
> > > > +- compatible: should contain "hisilicon,hi3660-dwc3" for HiSi SoC
> > > > +- clocks: A list of phandle + clock-specifier pairs for the
> > > > + clocks listed in clock-names
> > > > +- clock-names: Should contain the following:
> > > > + "clk_usb3phy_ref" Phy reference clk
> > > It's not good idea to apply phy's clock in dwc3's node
...
> > Given the name clk_usb3phy_ref I'm assuming its a phy reference clock,
> > but I honestly don't know if I'm getting that wrong. It all seems to
> > be leveraging the fact that the dwc-of-simple driver batch enables and
> > disables all the clocks w/o really looking at the names.
> >
...
> If it's phy clock, we should enable/disable it in phy driver, maybe we'd
> better ask for help from Yu Chen

So I've been looking around the existing code and I'm not sure how we
got to clk_usb3phy_ref here.

Really it is the HI3660_CLK_ABB_USB, who's name is "clk_abb_usb" and
who's parent is "clk_gate_usb_tcxo_en"

So I'm thinking just specifying clk_abb_usb is more accurate here?

Does that sound reasonable?

thanks
-john