airo: use generic power management

Drivers using legacy power management .suspen()/.resume() callbacks
have to manage PCI states and device's PM states themselves. They also
need to take care of standard configuration registers.

Switch to generic power management framework using a single
"struct dev_pm_ops" variable to take the unnecessary load from the driver.
This also avoids the need for the driver to directly call most of the PCI
helper functions and device power state control functions, as through
the generic framework PCI Core takes care of the necessary operations,
and drivers are required to do only device-specific jobs.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200728114128.1218310-1-vaibhavgupta40@gmail.com

drivers/net/wireless/cisco/airo.c

@@ -74,16 +74,19 @@ MODULE_DEVICE_TABLE(pci, card_ids);
 
 static int airo_pci_probe(struct pci_dev *, const struct pci_device_id *);
 static void airo_pci_remove(struct pci_dev *);
-static int airo_pci_suspend(struct pci_dev *pdev, pm_message_t state);
-static int airo_pci_resume(struct pci_dev *pdev);
+static int __maybe_unused airo_pci_suspend(struct device *dev);
+static int __maybe_unused airo_pci_resume(struct device *dev);
+
+static SIMPLE_DEV_PM_OPS(airo_pci_pm_ops,
+			 airo_pci_suspend,
+			 airo_pci_resume);
 
 static struct pci_driver airo_driver = {
-	.name     = DRV_NAME,
-	.id_table = card_ids,
-	.probe    = airo_pci_probe,
-	.remove   = airo_pci_remove,
-	.suspend  = airo_pci_suspend,
-	.resume   = airo_pci_resume,
+	.name      = DRV_NAME,
+	.id_table  = card_ids,
+	.probe     = airo_pci_probe,
+	.remove    = airo_pci_remove,
+	.driver.pm = &airo_pci_pm_ops,
 };
 #endif /* CONFIG_PCI */
 
@@ -5573,9 +5576,9 @@ static void airo_pci_remove(struct pci_dev *pdev)
 	pci_disable_device(pdev);
 }
 
-static int airo_pci_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused airo_pci_suspend(struct device *dev_d)
 {
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct net_device *dev = dev_get_drvdata(dev_d);
 	struct airo_info *ai = dev->ml_priv;
 	Cmd cmd;
 	Resp rsp;
@@ -5591,25 +5594,21 @@ static int airo_pci_suspend(struct pci_dev *pdev, pm_message_t state)
 		return -EAGAIN;
 	disable_MAC(ai, 0);
 	netif_device_detach(dev);
-	ai->power = state;
+	ai->power = PMSG_SUSPEND;
 	cmd.cmd = HOSTSLEEP;
 	issuecommand(ai, &cmd, &rsp);
 
-	pci_enable_wake(pdev, pci_choose_state(pdev, state), 1);
-	pci_save_state(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
+	device_wakeup_enable(dev_d);
 	return 0;
 }
 
-static int airo_pci_resume(struct pci_dev *pdev)
+static int __maybe_unused airo_pci_resume(struct device *dev_d)
 {
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct net_device *dev = dev_get_drvdata(dev_d);
 	struct airo_info *ai = dev->ml_priv;
-	pci_power_t prev_state = pdev->current_state;
+	pci_power_t prev_state = to_pci_dev(dev_d)->current_state;
 
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-	pci_enable_wake(pdev, PCI_D0, 0);
+	device_wakeup_disable(dev_d);
 
 	if (prev_state != PCI_D1) {
 		reset_card(dev, 0);