The (dev->irq && dev->irq >= 0xF) comparison in the code snippet
below should read (dev->irq && dev->irq <= 0xF), if the comments
are correct.  This is taken from line 356 or so in drivers/acpi/pci_irq.c.

I haven't personally noticed any problems caused by this, but stumbled
over it when looking for a way to get my Libretto 100CT's CardBus interface
to give a IRQ to a USB card.

Relevant code:

        /*
         * No IRQ known to the ACPI subsystem - maybe the BIOS / 
         * driver reported one, then use it. Exit in any case.
         */
        if (!irq) {
                printk(KERN_WARNING PREFIX "No IRQ known for interrupt pin %c of
 device %s", ('A' + pin), pci_name(dev));
                /* Interrupt Line values above 0xF are forbidden */
                if (dev->irq && dev->irq >= 0xF) {
                        printk(" - using IRQ %d\n", dev->irq);
                        return_VALUE(dev->irq);
                }
                else {
                        printk("\n");
                        return_VALUE(0);
                }
        }