Hi Rob,

> From: Rob Herring, Sent: Saturday, May 12, 2018 1:07 AM
> 
> On Mon, May 7, 2018 at 9:43 PM, Yoshihiro Shimoda
> <yoshihiro.shimoda...@renesas.com> wrote:
> > Hi Rob,
> >
> > Sorry for the delayed response. I had a vacation in last week.
> >
> >> From: Rob Herring, Sent: Saturday, April 28, 2018 5:06 AM
> >>
> >> On Thu, Apr 26, 2018 at 08:26:41PM +0900, Yoshihiro Shimoda wrote:
> >> > This patch adds a new documentation for Renesas R-Car USB 3.0 role
> >> > switch that can change the USB 3.0 role to either host or peripheral
> >> > by a hardware register that is included in USB3.0 peripheral module.
> >> >
> >> > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com>
> >> > ---
> >> >  .../bindings/usb/renesas,rcar-usb3-role-sw.txt     | 47 
> >> > ++++++++++++++++++++++
> >> >  1 file changed, 47 insertions(+)
> >> >  create mode 100644 
> >> > Documentation/devicetree/bindings/usb/renesas,rcar-usb3-role-sw.txt
> >> >
> >> > diff --git 
> >> > a/Documentation/devicetree/bindings/usb/renesas,rcar-usb3-role-sw.txt
> >> b/Documentation/devicetree/bindings/usb/renesas,rcar-usb3-role-sw.txt
> >> > new file mode 100644
> >> > index 0000000..e074c03
> >> > --- /dev/null
> >> > +++ b/Documentation/devicetree/bindings/usb/renesas,rcar-usb3-role-sw.txt
> >> > @@ -0,0 +1,47 @@
> >> > +Renesas Electronics R-Car USB 3.0 role switch
> >> > +
> >> > +A renesas_usb3's node can contain this node.
> >> > +
> >> > +Required properties:
> >> > + - compatible: Must contain "renesas,rcar-usb3-role-switch".
> >> > +
> >> > +Required nodes:
> >> > + - The connection to a usb3.0 host node needs by using OF graph 
> >> > bindings.
> >> > +  - port@0 = USB 3.0 host port
> >> > +  - port@1 = USB 3.0 peripheral port
> >> > +
> >> > +Example of R-Car H3 ES2.0:
> >> > +   usb3_peri0: usb@ee020000 {
> >> > +           compatible = "renesas,r8a7795-usb3-peri",
> >> > +                        "renesas,rcar-gen3-usb3-peri";
> >> > +           reg = <0 0xee020000 0 0x400>;
> >> > +           interrupts = <GIC_SPI 104 IRQ_TYPE_LEVEL_HIGH>;
> >> > +           clocks = <&cpg CPG_MOD 328>;
> >> > +           power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
> >> > +           resets = <&cpg 328>;
> >> > +
> >> > +           usb3-role-sw {
> >> > +                   compatible = "renesas,rcar-usb3-role-switch";
> >>
> >> You don't define any h/w resources. How is this device accessed?
> >
> > This device accesses one of registers in the usb3_peri0.
> > In the detail, the usb3-role-sw uses 0xee020218 (32-bit register) only.
> > (Unfortunately, the hardware design is not good...)
> >
> > In this case, should I describe the following in the usb3-role-sw node?
> >
> >         reg = <0 0xee020218 0 4>;
> >
> > Or, shouldn't I add the usb3-role-sw node and a driver for usb3_peri0 should
> > take care for it?
> 
> IMO, the driver should take care of it.

Thank you for the reply. I'll modify the usb3_peri0 driver for role switch.

Best regards,
Yoshihiro Shimoda

> Rob

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