From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> 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. The symptom of the problem is, for example, that when a PCI USB controller is affected, 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). Reported-and-tested-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Acked-by: Matthew Garrett <mjg59@xxxxxxxxxxxxx> Cc: 3.7+ <stable@xxxxxxxxxxxxxxx> --- drivers/pci/pci-acpi.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) Index: linux-pm/drivers/pci/pci-acpi.c =================================================================== --- linux-pm.orig/drivers/pci/pci-acpi.c +++ linux-pm/drivers/pci/pci-acpi.c @@ -53,14 +53,15 @@ static void pci_acpi_wake_dev(acpi_handl return; } - if (!pci_dev->pm_cap || !pci_dev->pme_support - || pci_check_pme_status(pci_dev)) { - if (pci_dev->pme_poll) - pci_dev->pme_poll = false; + /* Clear PME Status if set. */ + if (pci_dev->pme_support) + pci_check_pme_status(pci_dev); - pci_wakeup_event(pci_dev); - pm_runtime_resume(&pci_dev->dev); - } + if (pci_dev->pme_poll) + pci_dev->pme_poll = false; + + pci_wakeup_event(pci_dev); + pm_runtime_resume(&pci_dev->dev); if (pci_dev->subordinate) pci_pme_wakeup_bus(pci_dev->subordinate); -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html