adm8211: 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.

In the case of adm8211, after removing PCI helper functions, .suspend()
and .resume() became empty-body functions. Hence, define them NULL and
use dev_pm_ops.

Compile-tested only.
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200629035031.169670-1-vaibhavgupta40@gmail.com

drivers/net/wireless/admtek/adm8211.c

@@ -1976,35 +1976,20 @@ static void adm8211_remove(struct pci_dev *pdev)
 }
 
 
-#ifdef CONFIG_PM
-static int adm8211_suspend(struct pci_dev *pdev, pm_message_t state)
-{
-	pci_save_state(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
-	return 0;
-}
-
-static int adm8211_resume(struct pci_dev *pdev)
-{
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-	return 0;
-}
-#endif /* CONFIG_PM */
-
+#define adm8211_suspend NULL
+#define adm8211_resume NULL
 
 MODULE_DEVICE_TABLE(pci, adm8211_pci_id_table);
 
+static SIMPLE_DEV_PM_OPS(adm8211_pm_ops, adm8211_suspend, adm8211_resume);
+
 /* TODO: implement enable_wake */
 static struct pci_driver adm8211_driver = {
 	.name		= "adm8211",
 	.id_table	= adm8211_pci_id_table,
 	.probe		= adm8211_probe,
 	.remove		= adm8211_remove,
-#ifdef CONFIG_PM
-	.suspend	= adm8211_suspend,
-	.resume		= adm8211_resume,
-#endif /* CONFIG_PM */
+	.driver.pm	= &adm8211_pm_ops,
 };
 
 module_pci_driver(adm8211_driver);