realtek/8139cp: use generic power management

compile-tested only

With legacy PM hooks, it was the responsibility
of a driver to manage PCI states and also
device's power state. The generic approach is
to let PCI core handle the work.

The suspend callback enables/disables PCI wake
on the basis of "cp->wol_enabled" variable
which is unknown to PCI core. To utilise its
need, call device_set_wakeup_enable().
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/8139cp.c

@@ -2054,10 +2054,9 @@ static void cp_remove_one (struct pci_dev *pdev)
 	free_netdev(dev);
 }
 
-#ifdef CONFIG_PM
-static int cp_suspend (struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused cp_suspend(struct device *device)
 {
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct net_device *dev = dev_get_drvdata(device);
 	struct cp_private *cp = netdev_priv(dev);
 	unsigned long flags;
 
@@ -2075,16 +2074,14 @@ static int cp_suspend (struct pci_dev *pdev, pm_message_t state)
 
 	spin_unlock_irqrestore (&cp->lock, flags);
 
-	pci_save_state(pdev);
-	pci_enable_wake(pdev, pci_choose_state(pdev, state), cp->wol_enabled);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
+	device_set_wakeup_enable(device, cp->wol_enabled);
 
 	return 0;
 }
 
-static int cp_resume (struct pci_dev *pdev)
+static int __maybe_unused cp_resume(struct device *device)
 {
-	struct net_device *dev = pci_get_drvdata (pdev);
+	struct net_device *dev = dev_get_drvdata(device);
 	struct cp_private *cp = netdev_priv(dev);
 	unsigned long flags;
 
@@ -2093,10 +2090,6 @@ static int cp_resume (struct pci_dev *pdev)
 
 	netif_device_attach (dev);
 
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-	pci_enable_wake(pdev, PCI_D0, 0);
-
 	/* FIXME: sh*t may happen if the Rx ring buffer is depleted */
 	cp_init_rings_index (cp);
 	cp_init_hw (cp);
@@ -2111,7 +2104,6 @@ static int cp_resume (struct pci_dev *pdev)
 
 	return 0;
 }
-#endif /* CONFIG_PM */
 
 static const struct pci_device_id cp_pci_tbl[] = {
         { PCI_DEVICE(PCI_VENDOR_ID_REALTEK,     PCI_DEVICE_ID_REALTEK_8139), },
@@ -2120,15 +2112,14 @@ static const struct pci_device_id cp_pci_tbl[] = {
 };
 MODULE_DEVICE_TABLE(pci, cp_pci_tbl);
 
+static SIMPLE_DEV_PM_OPS(cp_pm_ops, cp_suspend, cp_resume);
+
 static struct pci_driver cp_driver = {
 	.name         = DRV_NAME,
 	.id_table     = cp_pci_tbl,
 	.probe        =	cp_init_one,
 	.remove       = cp_remove_one,
-#ifdef CONFIG_PM
-	.resume       = cp_resume,
-	.suspend      = cp_suspend,
-#endif
+	.driver.pm    = &cp_pm_ops,
 };
 
 module_pci_driver(cp_driver);