Re: [PATCH/RFC 0/2] Zorro modalias support

[Michael Schmitz <schmitz@mail.biophys.uni-duesseldorf.de>]

> > > What do you think?
> >
> > We would need something like that anyway, in order to convert drivers to
> > the new generic driver model, if I understand it right (the only driver
>
> The alternative is to keep (convert to, for some) them as platform
> devices. But that means no auto-load based on modalias.

Right - platform device was the name I keep forgetting ....

> > Re: bus type - multiplatform support is all dead anyway so we could
> > instead call it 'host' or 'm68k' and collect all on-board stuff there. And
>
> I prefer to call it by the platform name, though (see below).
>
> > I count Nubus/Zorro as on-board here. Just keeping in mind how I got my
> > BUS_ATARI in the input patch shot down.
>
> But we do have BUS_ATARI in <linux/input.h> now ;-)

I was planning on removing that again ... thought it got vetoed.

> > Am I mixing things up?
>
> I think so...
>
> Nubus and Zorro are definitely separate buses, as they support automatic
> probing.
>
> Most other `system bus' hardware doesn't have to be probed (in the ISA
> bang-a-few-ports-and-we'll-see sense) on m68k. We use
> {amiga,atari,mac}_hw_present to find out if something exists.

OK; so host/m68k/system/onboard/whatever, nubus and zorro should be
sufficient.

>
> So we could easily have in arch/*/config.c:
>
>     if ({AMIGA,ATARI,MAC}HW_PRESENT(XXX))
> 	register_XXX_device();
>     if ({AMIGA,ATARI,MAC}HW_PRESENT(YYY))
> 	register_YYY_device();
>     ...
>
> For XXX, YYY = GRAPHICS, KEYBOARD, BUILTIN_SCSI, ...
> and we have our `system bus'. Devices could be numbered just starting from
> 1 (or use the {amiga,atari,mac}_hw_present numbers? But we don't need
> devices for all of them, at least on Amiga), as we control what's there

Is the plan to move any or all of these to the platfoem driver or later
code at all?

> anyway. Module alias would then be of the form `{amiga,atari,mac}:%u'.
> See why I don't want to call it `host' or `m68k'?
> Hmm, maybe we should call it `host' or `m68k', to make it even more generic
> and use `host:{amiga,atari,mac}%u' for module aliases? One day other
> platforms may want to start using it, too...
>
> A `git grep 'struct bus_type.*= {' definitely shows a few `system
> buses'. It's even used for SoCs, which is in some sense very similar to
> Amiga, Atari, and Mac (it's just that VLSI wasn't sufficiently advanced in the
> eighties to give us single-chip solutions).

OK, needs more thought before deciding on a name I guess.

	Michael