[PATCH v4 2/3] usb: dwc3: dwc3-st: Add st-dwc3 devicetree bindings documentation

Peter Griffin peter.griffin at linaro.org
Thu Aug 21 06:33:40 PDT 2014


Hi Felipe,

Thanks for reviewing, see my comments below: -

On Wed, 20 Aug 2014, Felipe Balbi wrote:

> > +	dwc3: dwc3 at 9900000 {
> > +		compatible	= "snps,dwc3";
> > +		reg		= <0x09900000 0x100000>;
> > +		interrupts	= <GIC_SPI 155 IRQ_TYPE_NONE>;
> > +		dr_mode		= "host"
> > +		usb-phy		= <&usb3_phy>;
> > +		phy-names	= "usb2-phy";
> > +		phys		= <&usb2_picophy2>;
> 
> why are you using different binding for usb2 and usb3 phys ? Why can't
> you just:
> 
> 	phys-names	= "usb2-phy", "usb3-phy";
> 	phys		= <&usb2_picophy2>, <&usb3_phy>;
> 
> ??

Currently (in the vendor tree) one of the phys lives in drivers/usb/phy and the other in drivers/phy.
I believe that is because one is only a usb phy and the other is a multi function phy which can drive
PCI-E or USB3.

So to make that work, when dwc3/core.c gets the PHYS in dwc3_core_get_phy() we need to use the different
bindings.

I think we are the only platform using "one of each", but luckily dwc3_core_get_phy()
has been written generically enough that it "just works" :-).

regards,

Peter.



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