Re: [PATCH] Stop pmac_zilog from abusing 8250's device numbers.

Brad Boyer
2007-04-04T00:25:44Z

On Tue, Apr 03, 2007 at 07:57:22PM -0400, David Woodhouse wrote:
> > The TTY_MAJOR should have never belonged to 8250.c in the first place.
> > I know it's just my opinion, but I think this major device should be
> > owned by the serial core, and it shouldn't matter what chip drives each
> > individual port. Each hardware driver should just register with the
> > core how many ports it has and should be allocated from the same range.
>
> Yeah, because that works out really well for Ethernet devices and SCSI
> disks, with different numbers every day of the week according to what
> order we happen to load drivers in. :)

It just leads to the problem ethernet has on BSD/Solaris/etc. You have
to ask yourself "is the ethernet on this system le0 or hme0 or maybe
something else entirely?" in this case. I agree it does solve the issue
of detection order breaking the configuration, but it is less than ideal.
I think the issue of the devices shuffling around is less likely to be
a problem on serial, although we don't have the nice uniqueness of
hardware identifiers that was used to do device renaming in ethernet.

I suppose my opinion on this shows that I didn't come from the x86
side of Linux. The breakdown on this argument seems to have always
been that the x86 people wanted 8250 to own ttyS* and most others
wanted it shared. I know it was that way when m68k tried to merge
in their serial framework that did allow such sharing across any
number of hardware drivers.

Brad Boyer
flar@allandria.com