Re: [kbuild-devel] Re: [patch] kernel config 3/N - move sound into drivers/media

[Arnd Bergmann]

On Wednesday 14 August 2002 07:49, Peter Samuelson wrote:
> [Kai Germaschewski]
> > It comes of the cost of testing for the architecture, since
> > e.g. s390 does not want to include most of drivers/*, but that means
> > we'd actually collect this knowledge at a centralized place.
>
> What we need is an easy way to check for any arch.  CONFIG_ARCH_S390
> is the right idea (though s390x sets it as well, not sure if that's
> good or bad). 

It's not logical, but it tends to help because it's what's meant most
of the time. I don't know a single place in the kernel where you want
to test for (CONFIG_ARCH_S390 && !CONFIG_ARCH_S390X).

Rather than making everything depend on CONFIG_ARCH_THIS && CONFIG_ARCH_THAT,
I'd prefer if every driver depended on its bus type. With the new driver
model, every driver has a clearly defined bus type and driver class,
so it would be logical to have that driver option exactly when these two
are enabled. Of course, that probably means a huge amount of work but it 
helps avoid problems when a new architecture is added or an existing one
gets a new bus.
E.g., s390 used to have no support for SCSI, but with the zfcp driver
we enable drivers/scsi/Config.in, so now we get a lot of questions about
drivers that won't work. Enclosing the drivers in "CONFIG_ARCH_s390" != "y"
does help us, but it would still be wrong to do that for a Sparc kernel
that supports some of the PCI cards but not the ISA ones.

	Arnd <><