PCI/PM: Resume device before shutdown

Some actions during shutdown need device to be in D0 state, such as
MSI shutdown etc, so resume device before shutdown.

Without this patch, a device may not be enumerated after a kexec
because the corresponding bridge is not in D0, so that
configuration space of the device is not accessible.

Signed-off-by: Huang Ying <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
CC: [email protected]		# v3.6+

Author: yhuang-intel

drivers/pci/pci-driver.c

@@ -398,6 +398,8 @@ static void pci_device_shutdown(struct device *dev)
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	struct pci_driver *drv = pci_dev->driver;
 
+	pm_runtime_resume(dev);
+
 	if (drv && drv->shutdown)
 		drv->shutdown(pci_dev);
 	pci_msi_shutdown(pci_dev);
@@ -408,16 +410,6 @@ static void pci_device_shutdown(struct device *dev)
 	 * continue to do DMA
 	 */
 	pci_disable_device(pci_dev);
-
-	/*
-	 * Devices may be enabled to wake up by runtime PM, but they need not
-	 * be supposed to wake up the system from its "power off" state (e.g.
-	 * ACPI S5).  Therefore disable wakeup for all devices that aren't
-	 * supposed to wake up the system at this point.  The state argument
-	 * will be ignored by pci_enable_wake().
-	 */
-	if (!device_may_wakeup(dev))
-		pci_enable_wake(pci_dev, PCI_UNKNOWN, false);
 }
 
 #ifdef CONFIG_PM