Re: [PATCH 05/12] PCI: add pci_swizzle_interrupt_pin()

David Howells
2008-12-11T17:36:25Z

Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:

> +/**
> + * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
> + * @dev: the PCI device
> + * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
> + *
> + * The PCI-to-PCI bridge specification requires INTx swizzling for
> + * devices behind bridges on add-in cards. This performs the swizzle
> + * for one level of bridge.
> + */

Better.

> +u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
> +{
> + /* This implements Table 9-1 of the PCI-to-PCI bridge spec */

I'd recommend merging this comment into the banner.

> + return (((pin - 1) + PCI_SLOT(dev->devfn)) % 4) + 1;
> +}
> +

David