[PATCH 1/5 v3] usb: host: add DT bindings for faraday fotg2

Linus Walleij linus.walleij at linaro.org
Tue Apr 25 04:12:38 EDT 2017

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

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).

I hope I didn't get anything wrong here :/

Linus Walleij

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