[PATCH 1/5 v3] usb: host: add DT bindings for faraday fotg2
Hans Ulli Kroll
ulli.kroll at googlemail.com
Tue Apr 25 15:07:47 EDT 2017
Hi Linus
On Tue, 25 Apr 2017, Linus Walleij wrote:
> On Mon, Apr 24, 2017 at 6:53 PM, Hans Ulli Kroll
> <ulli.kroll at googlemail.com> wrote:
>
> > Got NAK'ed from Rob on some ealier round due missing "device mode" on this
> > IP. I've blatantly overrided this to a host only driver.
> >
> > These are the needed changes in DT to support both modes
> > Note the -dr at the end of fotg210, to reflect this in an dual role device
>
> OK I understood the discussion such that the compatible should
> simply be ""faraday,fotg210" as that is the name of the hardware
> IP block. This is the name of the hardware name in the Faraday
> page:
> http://www.faraday-tech.com/html/Product/IPProduct/InterfaceIP/USB2_0.htm
>
> Any other string implies how it is used, so that was what I understood
> as the reason to reject it with the "-hcd" (host controller device) suffix.
>
> > +- dr_mode : indicates the working mode for "fotg210-dr" compatible
> > + controllers. Can be "host", "peripheral". Default to
> > + "host" if not defined for backward compatibility.
>
> This seems right, so it is part of the generic bindings, correct?
>
> > usb at 68000000 {
> > - compatible = "cortina,gemini-usb", "faraday,fotg210";
> > + compatible = "cortina,gemini-usb", "faraday,fotg210-dr";
>
> But this would be wrong, because the compatible should only
> indicate what kind of hardware it is, not how it is going to be used
> (whether as host only, slave only or dual-role (OTG).
>
for compatible I think yes.
But in Rob's opinion we missed the device part of the controller.
Greetings
Hans Ulli Kroll
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