Re: [PATCH] PCI: Add pci shutdown ability

[Adam Belay <ambx1@neo.rr.com>]

On Mon, Apr 25, 2005 at 10:42:07PM +0200, Pavel Machek wrote:
> Hi!
> 
> > Well it seems that people are starting to want to hook the reboot
> > notifier, or the device shutdown facility in order to properly shutdown
> > pci drivers to make kexec work nicer.
> > 
> > So here's a patch for the PCI core that allows pci drivers to now just
> > add a "shutdown" notifier function that will be called when the system
> > is being shutdown.  It happens just after the reboot notifier happens,
> > and it should happen in the proper device tree order, so everyone should
> > be happy.
> > 
> > Any objections to this patch?
> 
> Yes.
> 
> I believe it should just do suspend(PMSG_SUSPEND) before system
> shutdown. If you think distintion between shutdown and suspend is
> important (I am not 100% convinced it is), we can just add flag
> saying "this is system shutdown".

So if I understand this correctly, you'd like to manually turn off devices
during a power off.  I believe the ACPI spec recommends this for S4 (but also
to leave on wake devices), but not necessarily S5.  Still it may be a good
idea.  Comments?

> 
> Actually this patch should be in the queue somewhere... We had it in
> suse trees for a long time, and IMO it can solve problem easily.

Yeah, that's what I had in mind when I mentioned PMSG_FREEZE.  It seems
to replace "shutdown" in many ways, is this correct?

Thanks,
Adam