PCI PM: Fix handling of devices without PM support by pci_target_state()

commit d2abdf62882d982c58e7a6b09ecdcfcc28075e2e upstream.

If a PCI device is not power-manageable either by the platform, or
with the help of the native PCI PM interface, pci_target_state() will
return either PCI_D3hot, or PCI_POWER_ERROR for it, depending on
whether or not the device is configured to wake up the system.  Alas,
none of these return values is correct, because each of them causes
pci_prepare_to_sleep() to return error code, although it should
complete successfully in such a case.

Fix this problem by making pci_target_state() always return PCI_D0
for devices that cannot be power managed.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 1a91bf9687af969c69f26c8e67fca08747c0d426..1e6c83e92bdd6ddb91d40c5a554c503d95d7a7cb 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1282,15 +1282,14 @@ pci_power_t pci_target_state(struct pci_dev *dev)
                default:
                        target_state = state;
                }
+       } else if (!dev->pm_cap) {
+               target_state = PCI_D0;
        } else if (device_may_wakeup(&dev->dev)) {
                /*
                 * Find the deepest state from which the device can generate
                 * wake-up events, make it the target state and enable device
                 * to generate PME#.
                 */
-               if (!dev->pm_cap)
-                       return PCI_POWER_ERROR;
-
                if (dev->pme_support) {
                        while (target_state
                              && !(dev->pme_support & (1 << target_state)))