On Mon, Oct 7, 2019 at 2:07 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
>
> On Mon, Oct 7, 2019 at 11:38 AM Rob Herring <robh+dt@xxxxxxxxxx> wrote:
> >
> > On Mon, Oct 7, 2019 at 12:56 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > >
> > > Add necessary compatible flag for HiSi's DWC3 so
> > > dwc3-of-simple will probe.
> > >
> > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> > > Cc: Felipe Balbi <balbi@xxxxxxxxxx>
> > > Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> > > Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> > > Cc: Mark Rutland <mark.rutland@xxxxxxx>
> > > Cc: Yu Chen <chenyu56@xxxxxxxxxx>
> > > Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> > > Cc: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> > > Cc: linux-usb@xxxxxxxxxxxxxxx
> > > Cc: devicetree@xxxxxxxxxxxxxxx
> > > Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
> > > ---
> > > v2: Tweaked clock names as clk_usb3phy_ref didn't seem right.
> > > ---
> > > .../devicetree/bindings/usb/hisi,dwc3.txt | 52 +++++++++++++++++++
> > > 1 file changed, 52 insertions(+)
> > > create mode 100644 Documentation/devicetree/bindings/usb/hisi,dwc3.txt
> >
> > Can you make this a schema.
>
> Sorry, I'm not sure exactly what you're asking. I'm guessing from
> grepping around you want the bindings in yaml instead (I see a few
> examples)?
Yes.
> Is there some pointer to documentation? The
> Documentation/devicetree/bindings/writing-bindings.txt file doesn't
> seem to say much on it.
You mean Documentation/devicetree/writing-schemas.rst? There's that
and Documentation/devicetree/bindings/example-schema.yaml which has a
bunch of annotations on what each part means.
> > > diff --git a/Documentation/devicetree/bindings/usb/hisi,dwc3.txt b/Documentation/devicetree/bindings/usb/hisi,dwc3.txt
> > > new file mode 100644
> > > index 000000000000..3a3e5c320f2a
> > > --- /dev/null
> > > +++ 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_abb_usb" USB reference clk
Probably 'ref' from dwc3.txt.
> > > + "aclk_usb3otg" USB3 OTG aclk
'bus_early'? IIRC, 'aclk' is the clock name for AXI bus clock.
> > > +
> > > +- assigned-clocks: Should be:
> > > + HI3660_ACLK_GATE_USB3OTG
> > > +- assigned-clock-rates: Should be:
> > > + 229Mhz (229000000) for HI3660_ACLK_GATE_USB3OTG
> > > +
> > > +Optional properties:
> > > +- resets: Phandle to reset control that resets core and wrapper.
> >
> > Looks like 4 resets though.
>
> Good point. I'll fix that up.
>
> > > +
> > > +Required child node:
> > > +A child node must exist to represent the core DWC3 IP block. The name of
> > > +the node is not important. The content of the node is defined in dwc3.txt.
> > > +
> > > +Example device nodes:
> > > +
> > > + usb3: hisi_dwc3 {
> > > + compatible = "hisilicon,hi3660-dwc3";
> > > + #address-cells = <2>;
> > > + #size-cells = <2>;
> > > + ranges;
> > > +
> > > + clocks = <&crg_ctrl HI3660_CLK_ABB_USB>,
> > > + <&crg_ctrl HI3660_ACLK_GATE_USB3OTG>;
> > > + clock-names = "clk_abb_usb", "aclk_usb3otg";
> > > +
> > > + assigned-clocks = <&crg_ctrl HI3660_ACLK_GATE_USB3OTG>;
> > > + assigned-clock-rates = <229 000 000>;
> > > + resets = <&crg_rst 0x90 8>,
> > > + <&crg_rst 0x90 7>,
> > > + <&crg_rst 0x90 6>,
> > > + <&crg_rst 0x90 5>;
> > > +
> > > + dwc3: dwc3@ff100000 {
> >
> > If it's only clocks and resets for the wrapper node, just make this
> > all one node.
>
> Just to make sure I'm following, you're suggesting I put all the
> clocks/resets in the dwc3 node (renamed to usb for the node name) and
> not add the wrapper?
Yes.
> I'll have to see if that's possible. The generic dwc3 binding wants 3
> clocks, but I only have two in the code I've worked with (similarly it
> seems to only want two resets, not 4) so I'll have to see if I can
> figure out how to adapt that.
Possible since commit fe8abf332b8f ("usb: dwc3: support clocks and
resets for DWC3 core").
>
> If that approach is preferred, do I also no longer need a separate
> binding document/schema?
Correct. And then no need to convert to schema yet (though feel free
to convert dwc3.txt :)).
Rob
