Re: [RFC 2/5] i3c: Add core I3C infrastructure

From: Boris Brezillon
Date: Tue Aug 01 2017 - 11:21:05 EST

On Tue, 1 Aug 2017 17:01:08 +0200
Wolfram Sang <wsa@xxxxxxxxxxxxx> wrote:

> > I do not know of any real devices as of today (all my tests have been
> > done with a dummy/fake I3C slaves emulated with a slave IP),
> I see.
> > spec clearly describe what legacy/static addresses are for and one of
> > their use case is to connect an I3C device on an I2C bus and let it act
> > as an I2C device.
> OK. That makes it more likely.
> > Unless you want your device (likely a sensor) to be compatible with both
> > I3C and I2C so that you can target even more people.
> Right. My question was if this is a realistic or more academic scenario.
> > I'm perfectly fine with the I3C / I2C framework separation. The only
> > minor problem I had with that was the inaccuracy of the
> > sysfs/device-model representation: we don't have one i2c and one i3c
> > bus, we just have one i3c bus with a mix of i2c and i3c devices.
> I understand that. What if I2C had the same seperation between the "bus"
> and the "master"?

Yep, it might work if we can register an i2c_adapter and pass it an
existing bus object. We'd still need a common base for i2c and i3c
busses, unless we consider the bus as an opaque "struct device *"