Re: [PATCH 8/9] PCI / ACPI / PM: Platform support for PCI PME wake-up (rev. 7)

Bjorn Helgaas
2010-02-05T23:57:17Z

On Sunday 10 January 2010 07:01:03 am Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
>
> Although the majority of PCI devices can generate PMEs that in
> principle may be used to wake up devices suspended at run time,
> platform support is generally necessary to convert PMEs into wake-up
> events that can be delivered to the kernel. If ACPI is used for this
> purpose, a PME generated by a PCI device will trigger the ACPI GPE
> associated with the device to generate an ACPI wake-up event that we
> can set up a handler for, provided that everything is configured
> correctly.

I think acpiphp needs a little attention after this patch. Gary
Hade noticed while testing Jesse's linux-next branch that acpiphp
complains like this:

acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
acpiphp: Slot [9] registered
acpiphp: Slot [10] registered
acpiphp_glue: failed to register interrupt notify handler
acpiphp: Slot [6] registered
acpiphp_glue: failed to register interrupt notify handler

I reproduced this on an HP rx3600 (ia64), and found that acpiphp
doesn't complain on commit 82533a617f453, but it *does* complain
on commit fb3383bb4ac6e, which seems to be this patch.

I haven't tried to debug it any farther than just noticing that
acpiphp starts complaining here, so I don't know what the right
fix is, or even if acpiphp is really broken.

I did use acpiphp to power-cycle a slot ("echo 0 > power"), and
it seemed to work despite the warnings. But I guess the notification
is probably not involved in that path; I suppose the notification
is like a latch or attention button interrupt or something.

Bjorn