1 files changed, 19 insertions, 12 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index aacf575c15cf..a5e6759c407b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1906,11 +1906,7 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
 	 * so that things like MSI message writing will behave as expected
 	 * (e.g. if the device really is in D0 at enable time).
 	 */
-	if (dev->pm_cap) {
-		u16 pmcsr;
-		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
-		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
-	}
+	pci_update_current_state(dev, dev->current_state);
 
 	if (atomic_inc_return(&dev->enable_cnt) > 1)
 		return 0;		/* already enabled */
@@ -2495,7 +2491,14 @@ static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable
 	if (enable) {
 		int error;
 
-		if (pci_pme_capable(dev, state))
+		/*
+		 * Enable PME signaling if the device can signal PME from
+		 * D3cold regardless of whether or not it can signal PME from
+		 * the current target state, because that will allow it to
+		 * signal PME when the hierarchy above it goes into D3cold and
+		 * the device itself ends up in D3cold as a result of that.
+		 */
+		if (pci_pme_capable(dev, state) || pci_pme_capable(dev, PCI_D3cold))
 			pci_pme_active(dev, true);
 		else
 			ret = 1;
@@ -2599,16 +2602,20 @@ static pci_power_t pci_target_state(struct pci_dev *dev, bool wakeup)
 	if (dev->current_state == PCI_D3cold)
 		target_state = PCI_D3cold;
 
-	if (wakeup) {
+	if (wakeup && dev->pme_support) {
+		pci_power_t state = target_state;
+
 		/*
 		 * Find the deepest state from which the device can generate
 		 * PME#.
 		 */
-		if (dev->pme_support) {
-			while (target_state
-			      && !(dev->pme_support & (1 << target_state)))
-				target_state--;
-		}
+		while (state && !(dev->pme_support & (1 << state)))
+			state--;
+
+		if (state)
+			return state;
+		else if (dev->pme_support & 1)
+			return PCI_D0;
 	}
 
 	return target_state;