Followup to: <E15UV8M-0005SE-00@the-village.bc.nu>
By author: Alan Cox <alan@lxorguk.ukuu.org.uk>
In newsgroup: linux.dev.kernel
>
> > The following would seem to be required to protect against
> > the case in which PnP BIOS reports an IRQ of 0 for a
> > parport with disabled IRQ. // Thomas jdthood_AT_yahoo.co.uk
>
> IRQ 0 is a legal valid IRQ. I suspect the problem is that pnpbios shouldnt
> be reporting an IRQ or we should be using some kind of NO_IRQ cookie
>
IRQ 0 is hardwired to the system timer in PC systems, though, so it
could simply be assumed that IRQ 0 will never be used for any other
purposes.
Reminds me back in the days when you had to worry about DRQs as well;
DRQ 0 was hardwired in the original PC but then became available in
the AT; there was a whole bunch of things that assumed DRQ 0 wasn't
usable, even though it was perfectly fine. Not to mention the
motherboard I had which would lock up solid if anything ever used
DRQ 5.
Good riddance, all this crap...
-hpa
-- <hpa@transmeta.com> at work, <hpa@zytor.com> in private! "Unix gives you enough rope to shoot yourself in the foot." http://www.zytor.com/~hpa/puzzle.txt <amsp@zytor.com> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Wed Aug 15 2001 - 21:00:21 EST