floppy: request and release only the ports we actually use
The floppy driver requests an I/O port it doesn't need, and sometimes this
causes a conflict with a motherboard device reported by PNPBIOS.
This patch makes the floppy driver request and release only the ports it
actually uses. It also factors out the request/release stuff and the
io-ports list so they're all in one place now.
but it requests 0x3f2-0x3f5 and 0x3f7, which includes the unused port
0x3f3.
Some BIOSes report 0x3f3 as a motherboard resource. The PNP system driver
reserves that, which causes a conflict when the floppy driver requests
0x3f2-0x3f5 later.
Philippe reported that this conflict broke the floppy driver between
2.6.11 and 2.6.22. His PNPBIOS reports these devices:
$ cat 00:03/id 00:03/resources # floppy device
PNP0700
state = active
io 0x3f4-0x3f5
io 0x3f2-0x3f2
Reference:
http://lkml.org/lkml/2009/1/31/162
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Philippe De Muyter <phdm@macqel.be> Reported-by: Philippe De Muyter <phdm@macqel.be> Tested-by: Philippe De Muyter <phdm@macqel.be> Cc: Adam M Belay <abelay@mit.edu> Cc: Robert Hancock <hancockrwd@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>