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

Brad Boyer flar at allandria.com
Wed Apr 4 08:10:02 EST 2007


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 at allandria.com




More information about the Linuxppc-dev mailing list