Re: i3c application

Boris Brezillon
2019-01-29T13:30:36Z

+Vitor who started a discussion around i3c-tools and the associate
kernel <-> userspace interface.

Hi Ryan,

On Tue, 29 Jan 2019 00:54:05 +0000
Ryan Chen <ryan_chen@aspeedtech.com> wrote:

> Hi all,
> I just work with I3C, does there have any application like i2c-tools I can used?

No, but I'll ask the same question I already asked Vitor: what would
you use i3c-tools for? What should it contain? I'm not against the
idea, but I'd like to delimit the scope of the userspace interface.

> Or any Linux i3c application I can have i3c slave and master loop test?

Not sure I get this request correctly. Are you talking about a dummy
slave driver that would return any data it receives to the TX queue
so that the next read request coming from the master returns what the
master wrote in its previous write access?

If that's what you have in mind, then it's definitely not supported.
But before we even consider doing that, we should first introduce the
concept of I3C slave controller and then decide how we want to expose
slave features. Note that Vitor and I disagree on the solution: I think
we should mimic the USB gadget approach (where you can attach a generic
profile to any USB device controller), and Vitor thinks slave IPs
should have their profile/feature-set hardcoded in the driver (which
works fine for hardcoded slave IPs, but is not that great if the slave
block is generic).

Regards,

Boris