> > Currently, there is no paradigm that all I2C busses must be fully
> > described. Enforcing it now all of a sudden is not too user-friendly,
> > or?
> 
> We're only enforcing it for systems that want to make use of this new
> API, so it's not breaking backward compatibility.

Well, even new systems might need to update old DTSIs which they
include.

> > Especially since calling read_byte once is not necessarily "great
> > length" in my book. If you have 8 cameras on a 400kHz bus, the 8 * 18
> > bits should take 360us if I am not mistaken?
> 
> That's assuming the first scanned address is free. There could also be
> I2C-controller I2C muxes or gates in front of the bus. Things can
> quickly get more expensive.

Not on a fully described bus, or? The first address will always be free.