Re: [RFC] PCI: Runtime power management

On Thu, 13 Aug 2009 01:29:25 +0100
Matthew Garrett [off-list ref] wrote:

I got a fixed BIOS from Dell and have been able to get this working
now. It seems entirely happy with USB, but I'd like some sanity
checks on whether I'm doing this correctly. There's certainly a
couple of quirks related to setting the ACPI GPE type that would need
a little bit of work in the ACPI layer, and it breaks ACPI-mediated
PCI hotplug though that's easy enough to fix by just calling into the
hotplug code from the core notifier.

This patch builds on top of Rafael's work on systemwide runtime power
management. It supports suspending and resuming PCI devices at
runtime, enabling platform wakeup events that allow the devices to
automatically resume when appropriate. It currently requires platform
support, but PCIe setups could be supported natively once native PCIe
PME code has been added to the kernel.

PCI bits look pretty good to me, though Rafael should take a look too.
Card readers and firewire could benefit from similar treatment, maybe
that would get us to .5W territory on some machines.

-- 
Jesse Barnes, Intel Open Source Technology Center