Re: new acpi utility functions

["Christoph Egger" <Christoph_Egger%gmx.de@localhost>]

> On Mon, Nov 30, 2009 at 08:10:10AM +0100, Christoph Egger wrote:
> > The purpose is to link ACPI and PCI drivers together in a
> > general way not just for power management.
> 
> Yes, I was aware of that. Perhaps what I was really saying is
> that nice work, this is much needed.
> 
> 117  +       /*
> 118  +        * ACPI spec: "The _BBN object is located under a
> 119  +        * PCI host bridge and must be unique for every
> 120  +        * host bridge within a segment since it is the PCI bus
> number."
> 121  +        */
> 122  +       rv = acpi_eval_integer(ad->ad_handle, "_BBN", &bus);
> 123  +       if (ACPI_FAILURE(rv))
> 124  +               return false;
> 
> Not that important, but I wonder if it is possible to
> alternatively obtain the bus number via the resources returned
> in _CRS? If so, it could be tried before bailing out.

_CRS is only usable on PCI root bridges to read both
PCI segment and PCI bus number.
PCI root bridges attach on PNP0A?? devices.

Christoph