[PATCH Quantal SRU] PCI / ACPI: Always resume devices on ACPI wakeup notifications

[Zhang, Xiong Y]

Without it, when the USB host controller is suspended, hotplug events will be lost.
OSVs with Haswell/Lynx Point support should backport this fix.

commit 24ad0ef9c8b946ed2abe681e4e44f4a1e643d882
Author: Rafael J. Wysocki <rafael.j.wysocki at intel.com<mailto:rafael.j.wysocki at intel.com>>
Date:   Thu Mar 28 11:07:29 2013 +0000

    PCI/ACPI: Always resume devices on ACPI wakeup notifications

    It turns out that the _Lxx control methods provided by some BIOSes
    clear the PME Status bit of PCI devices they handle, which means that
    pci_acpi_wake_dev() cannot really use that bit to check whether or
    not the device has signalled wakeup.

    One symptom of the problem is, for example, that when an affected PCI
    USB controller is runtime-suspended, then plugging in a new USB device
    into one of the controller's ports will not wake up the controller,
    which should happen.

    For this reason, make pci_acpi_wake_dev() always attempt to resume
    the device it is called for regardless of the device's PME Status bit
    value (that bit still has to be cleared if set at this point,
though).

thanks
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