cvs commit: src/sys/ia64/ia64 machdep.c

[M. Warner Losh]

In message: <4f339e2416fad9f0baab265cec8a744d at qubesoft.com>
            Doug Rabson <dfr at qubesoft.com> writes:
: 
: On 4 Feb 2005, at 16:36, M. Warner Losh wrote:
: 
: > In message: <5539563a425020d35ef1878057f4f85d at qubesoft.com>
: >             Doug Rabson <dfr at qubesoft.com> writes:
: > :
: > : On 4 Feb 2005, at 16:14, M. Warner Losh wrote:
: > :
: > : > In message: <84e9ba659174ea3f7c7b2930c0ae3759 at xcllnt.net>
: > : >             Marcel Moolenaar <marcel at xcllnt.net> writes:
: > : > : > I'm not sure if my approach is correct -- should different 
: > drivers
: > : > for
: > : > : > the same hardware share the same devclass?
: > : > :
: > : > : A datapoint: sio(4) and uart(4) are different drivers for the 
: > same
: > : > : hardware.
: > : > : They don't share the devclass.
: > : >
: > : > Neither do they share the same name.
: > :
: > : Just to make things clear, if two drivers use the same name, they 
: > will
: > : always share the devclass automatically (whether or not they use the
: > : same variable to reference the devclass) and will allocate
: > : non-conflicting unit numbers.
: >
: > Cool.  I'd thought I'd wound up with two instances of ed0 when I had
: > different devclasses in the if_ed_isa and if_ed_pci files once upon a
: > time...
: 
: This shouldn't be possible - both the driver registrations should go 
: through devclass_find_internal() to find their devclasses and this 
: always searches for an existing class before it creates one. If this 
: happens then its a serious bug...

I think I had this problem in 4.0-current before 4.0 release.  Maybe
there used to be a bug, or I did something stupid...

If this is the case, why then do we have the allocation of devclass in
the drivers and not just leave it to subr_bus.c?

Warner