Re: [PATCH v4 6/9] usb: dwc3: Rework resets initialization to be more flexible

From: Felipe Balbi
Date: Wed Oct 30 2019 - 05:01:56 EST


John Stultz <john.stultz@xxxxxxxxxx> writes:

> On Tue, Oct 29, 2019 at 2:17 AM Felipe Balbi <balbi@xxxxxxxxxx> wrote:
>> John Stultz <john.stultz@xxxxxxxxxx> writes:
>> > The dwc3 core binding specifies one reset.
>> >
>> > However some variants of the hardware my not have more.
>> ^^
>> may
>> According to synopsys databook, there's a single *input* reset signal on
>> this IP. What is this extra reset you have?
>> Is this, perhaps, specific to your glue layer around the synopsys ip?
> Likely (again, I unfortunately don't have a ton of detail on the hardware).
>> Should, perhaps, your extra reset be managed by the glue layer?
> So yes the dwc3-of-simple does much of this already (it handles
> multiple resets, and variable clocks), but unfortunately we seem to
> need new bindings for each device added? I think the suggestion from
> Rob was due to the sprawl of bindings for the glue code, and the extra
> complexity of the parent node. So I believe Rob just thought it made
> sense to collapse this down into the core?
> I'm not really passionate about either approach, and am happy to
> rework (as long as there is eventual progress :).
> Just let me know what you'd prefer.

Well, I was under the impression we were supposed to describe the
HW. Synopsys IP has a single reset input :-p