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Subject: Re: [PATCH v6 00/10] Add the I3C subsystem
To:     Boris Brezillon <boris.brezillon@bootlin.com>
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From:   Peter Rosin <peda@axentia.se>
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On 2018-07-20 12:05, Boris Brezillon wrote:
> On Fri, 20 Jul 2018 11:57:56 +0200 Peter Rosin <peda@axentia.se> wrote:
>> Maybe a bit-bang I3C master isn't feasible for some fundamental
>> reason?
> 
> No, it's clearly not. The way an I3C master is supposed to switch from
> open-drain to push-pull during a transaction or the concept of IBIs
> are the first things that come to mind, but I guess you have plenty of
> other reasons preventing you from implementing a i3c-bit-bang master.

Why can't a bit-banger switch from open-drain to push-pull? That's just
a matter of disconnecting some pull-ups, no? And maybe you know that no
device on your bus uses IBIs? Maybe none of reasons for why bit-banging
isn't feasible are applicable?

I.e. maybe there can be a I3C bit-banger that perhaps isn't generic and
isn't full-featured, but does work just fine in some specific setup?

Cheers,
Peter