1 files changed, 27 insertions, 17 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 60230da957e0..5d45e518a266 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1226,6 +1226,10 @@ static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout)
  *
  * On success, return 0 or 1, depending on whether or not it is necessary to
  * restore the device's BARs subsequently (1 is returned in that case).
+ *
+ * On failure, return a negative error code.  Always return failure if @dev
+ * lacks a Power Management Capability, even if the platform was able to
+ * put the device in D0 via non-PCI means.
  */
 int pci_power_up(struct pci_dev *dev)
 {
@@ -1242,9 +1246,6 @@ int pci_power_up(struct pci_dev *dev)
 		else
 			dev->current_state = state;
 
-		if (state == PCI_D0)
-			return 0;
-
 		return -EIO;
 	}
 
@@ -1302,8 +1303,12 @@ static int pci_set_full_power_state(struct pci_dev *dev)
 	int ret;
 
 	ret = pci_power_up(dev);
-	if (ret < 0)
+	if (ret < 0) {
+		if (dev->current_state == PCI_D0)
+			return 0;
+
 		return ret;
+	}
 
 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 	dev->current_state = pmcsr & PCI_PM_CTRL_STATE_MASK;
@@ -2415,10 +2420,13 @@ static void pci_pme_list_scan(struct work_struct *work)
 
 	mutex_lock(&pci_pme_list_mutex);
 	list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
-		if (pme_dev->dev->pme_poll) {
-			struct pci_dev *bridge;
+		struct pci_dev *pdev = pme_dev->dev;
+
+		if (pdev->pme_poll) {
+			struct pci_dev *bridge = pdev->bus->self;
+			struct device *dev = &pdev->dev;
+			int pm_status;
 
-			bridge = pme_dev->dev->bus->self;
 			/*
 			 * If bridge is in low power state, the
 			 * configuration space of subordinate devices
@@ -2426,14 +2434,20 @@ static void pci_pme_list_scan(struct work_struct *work)
 			 */
 			if (bridge && bridge->current_state != PCI_D0)
 				continue;
+
 			/*
-			 * If the device is in D3cold it should not be
-			 * polled either.
+			 * If the device is in a low power state it
+			 * should not be polled either.
 			 */
-			if (pme_dev->dev->current_state == PCI_D3cold)
+			pm_status = pm_runtime_get_if_active(dev, true);
+			if (!pm_status)
 				continue;
 
-			pci_pme_wakeup(pme_dev->dev, NULL);
+			if (pdev->current_state != PCI_D3cold)
+				pci_pme_wakeup(pdev, NULL);
+
+			if (pm_status > 0)
+				pm_runtime_put(dev);
 		} else {
 			list_del(&pme_dev->list);
 			kfree(pme_dev);
@@ -4927,7 +4941,6 @@ static int pcie_wait_for_link_status(struct pci_dev *pdev,
 int pcie_retrain_link(struct pci_dev *pdev, bool use_lt)
 {
 	int rc;
-	u16 lnkctl;
 
 	/*
 	 * Ensure the updated LNKCTL parameters are used during link
@@ -4939,17 +4952,14 @@ int pcie_retrain_link(struct pci_dev *pdev, bool use_lt)
 	if (rc)
 		return rc;
 
-	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnkctl);
-	lnkctl |= PCI_EXP_LNKCTL_RL;
-	pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
+	pcie_capability_set_word(pdev, PCI_EXP_LNKCTL, PCI_EXP_LNKCTL_RL);
 	if (pdev->clear_retrain_link) {
 		/*
 		 * Due to an erratum in some devices the Retrain Link bit
 		 * needs to be cleared again manually to allow the link
 		 * training to succeed.
 		 */
-		lnkctl &= ~PCI_EXP_LNKCTL_RL;
-		pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
+		pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL, PCI_EXP_LNKCTL_RL);
 	}
 
 	return pcie_wait_for_link_status(pdev, use_lt, !use_lt);