Re: ISA -> ISA_ (Re: [GIT PATCH] ACPI patches for 2.6.25-rc6)

Bjorn Helgaas
2008-03-26T18:43:35Z

On Wednesday 26 March 2008 11:24:41 am Alexey Starikovskiy wrote:
> Bjorn Helgaas wrote:
> > I'm curious about how this works. I disassembled the DSDT from
> > http://bugzilla.kernel.org/show_bug.cgi?id=4773 (I attached the disassembly
> > at http://bugzilla.kernel.org/attachment.cgi?id=15448&action=view), and
> > the _PRT contains "_SB" and "ISA" (no trailing underscores):
> >
> > Package (0x04)
> > {
> > 0x000DFFFF,
> > 0x00,
> > \_SB.PCI0.ISA.LNKA,
> > 0x00
> > }
> >
> > But by the time we get to acpi_pci_irq_add_entry(), we've added the
> > underscores somewhere (see
> > http://bugzilla.kernel.org/attachment.cgi?id=15423&action=view):
> >
> > 0000:00:0d[A] -> \_SB_.PCI0.ISA_.LNKA
> >
> > I don't know where this happens, but it certainly confused me, and
> > it seems like it could lead to other bugs.
> >
> ACPI is supposed to add trailing underscore for pad all names to 4 bytes.
> So ISA will be padded to ISA_.

The questions are "where does this happen?" and "why does it not
apply to other things like asus_acpi.c?"