Re: commit 7e92b4fc34 - x86, serial: convert legacy COM ports to platform devices - broke my serial console

[Shaohua Li <shaohua.li@intel.com>]

On Wed, 2007-07-25 at 17:37 -0700, Yinghai Lu wrote:
> On 7/25/07, Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
> > On Wednesday 25 July 2007 07:32:53 am Sébastien Dugué wrote:
> > > On Wed, 25 Jul 2007 07:16:44 -0600 Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
> > >
> > > > The _DDN is a "DOS device name", and the _UID is a "logical device ID
> > > > that does not change across reboots."  Both are optional, and PNPACPI
> > > > ignores them.  But maybe we could change PNPACPI to sort by them if
> > > > they are present.  I'll think about this a bit.
> > >
> > >   That would be nice, but I wish you good luck with all those
> > > crappy BIOSes out there.
> >
> > Yeah, it's an ugly world we live in.  Would you be able to try the
> > attached patch just for testing?  It should sort devices with the
> > same _HID by their _UID.  It doesn't have any effect on my systems,
> > because my devices are already ordered by _UID by default.  But I
> > think it should switch your COM1/COM2 ports back to the order you
> > expect.
> >
> > Yinghai, you mentioned the same issue on boxes with multiple root
> > bridges.  Any chance you could try this out there as well?
> >
> it doesn't solve pci_root_bus reverse problem.
> 
> is that too late for PNP0A03?
> 
> I wonder if we need to modify acpi_device_register to sort them.
The pci root driver is an acpi driver not a pnp driver, so Bjorn's patch
will not work. Maybe the ACPI core (ACPICA) should do the sort?

Thanks,
Shaohua