ixgbevf: use generic power management

With legacy PM, drivers themselves were responsible for managing the
device's power states and takes care of register states.

After upgrading to the generic structure, PCI core will take care of
required tasks and drivers should do only device-specific operations.

The driver was invoking PCI helper functions like pci_save/restore_state(),
and pci_enable/disable_device(), which is not recommended.

Compile-tested only.
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c

@@ -4297,13 +4297,10 @@ static int ixgbevf_change_mtu(struct net_device *netdev, int new_mtu)
 	return 0;
 }
 
-static int ixgbevf_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused ixgbevf_suspend(struct device *dev_d)
 {
-	struct net_device *netdev = pci_get_drvdata(pdev);
+	struct net_device *netdev = dev_get_drvdata(dev_d);
 	struct ixgbevf_adapter *adapter = netdev_priv(netdev);
-#ifdef CONFIG_PM
-	int retval = 0;
-#endif
 
 	rtnl_lock();
 	netif_device_detach(netdev);
@@ -4314,37 +4311,16 @@ static int ixgbevf_suspend(struct pci_dev *pdev, pm_message_t state)
 	ixgbevf_clear_interrupt_scheme(adapter);
 	rtnl_unlock();
 
-#ifdef CONFIG_PM
-	retval = pci_save_state(pdev);
-	if (retval)
-		return retval;
-
-#endif
-	if (!test_and_set_bit(__IXGBEVF_DISABLED, &adapter->state))
-		pci_disable_device(pdev);
-
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int ixgbevf_resume(struct pci_dev *pdev)
+static int __maybe_unused ixgbevf_resume(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct net_device *netdev = pci_get_drvdata(pdev);
 	struct ixgbevf_adapter *adapter = netdev_priv(netdev);
 	u32 err;
 
-	pci_restore_state(pdev);
-	/* pci_restore_state clears dev->state_saved so call
-	 * pci_save_state to restore it.
-	 */
-	pci_save_state(pdev);
-
-	err = pci_enable_device_mem(pdev);
-	if (err) {
-		dev_err(&pdev->dev, "Cannot enable PCI device from suspend\n");
-		return err;
-	}
-
 	adapter->hw.hw_addr = adapter->io_addr;
 	smp_mb__before_atomic();
 	clear_bit(__IXGBEVF_DISABLED, &adapter->state);
@@ -4365,10 +4341,9 @@ static int ixgbevf_resume(struct pci_dev *pdev)
 	return err;
 }
 
-#endif /* CONFIG_PM */
 static void ixgbevf_shutdown(struct pci_dev *pdev)
 {
-	ixgbevf_suspend(pdev, PMSG_SUSPEND);
+	ixgbevf_suspend(&pdev->dev);
 }
 
 static void ixgbevf_get_tx_ring_stats(struct rtnl_link_stats64 *stats,
@@ -4888,16 +4863,17 @@ static const struct pci_error_handlers ixgbevf_err_handler = {
 	.resume = ixgbevf_io_resume,
 };
 
+static SIMPLE_DEV_PM_OPS(ixgbevf_pm_ops, ixgbevf_suspend, ixgbevf_resume);
+
 static struct pci_driver ixgbevf_driver = {
 	.name		= ixgbevf_driver_name,
 	.id_table	= ixgbevf_pci_tbl,
 	.probe		= ixgbevf_probe,
 	.remove		= ixgbevf_remove,
-#ifdef CONFIG_PM
+
 	/* Power Management Hooks */
-	.suspend	= ixgbevf_suspend,
-	.resume		= ixgbevf_resume,
-#endif
+	.driver.pm	= &ixgbevf_pm_ops,
+
 	.shutdown	= ixgbevf_shutdown,
 	.err_handler	= &ixgbevf_err_handler
 };