misc/tifm_7xx1.c: use generic power management

Drivers should not use legacy power management as they have to manage power
states and related operations, for the device, themselves. This driver was
handling them with the help of PCI helper functions like
pci_save/restore_state(), pci_enable/disable_device(), etc.

With generic PM, all essentials will be handled by the PCI core. Driver
needs to do only device-specific operations.

The driver was also using pci_enable_wake(...,..., 0) to disable wake. Use
device_wakeup_disable() instead.

Compile-tested only.
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Link: https://lore.kernel.org/r/20200629081531.214734-4-vaibhavgupta40@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/tifm_7xx1.c

@@ -207,10 +207,9 @@ static void tifm_7xx1_switch_media(struct work_struct *work)
 	spin_unlock_irqrestore(&fm->lock, flags);
 }
 
-#ifdef CONFIG_PM
-
-static int tifm_7xx1_suspend(struct pci_dev *dev, pm_message_t state)
+static int __maybe_unused tifm_7xx1_suspend(struct device *dev_d)
 {
+	struct pci_dev *dev = to_pci_dev(dev_d);
 	struct tifm_adapter *fm = pci_get_drvdata(dev);
 	int cnt;
 
@@ -221,15 +220,13 @@ static int tifm_7xx1_suspend(struct pci_dev *dev, pm_message_t state)
 			tifm_7xx1_sock_power_off(fm->sockets[cnt]->addr);
 	}
 
-	pci_save_state(dev);
-	pci_enable_wake(dev, pci_choose_state(dev, state), 0);
-	pci_disable_device(dev);
-	pci_set_power_state(dev, pci_choose_state(dev, state));
+	device_wakeup_disable(dev_d);
 	return 0;
 }
 
-static int tifm_7xx1_resume(struct pci_dev *dev)
+static int __maybe_unused tifm_7xx1_resume(struct device *dev_d)
 {
+	struct pci_dev *dev = to_pci_dev(dev_d);
 	struct tifm_adapter *fm = pci_get_drvdata(dev);
 	int rc;
 	unsigned long timeout;
@@ -242,11 +239,6 @@ static int tifm_7xx1_resume(struct pci_dev *dev)
 	if (WARN_ON(fm->num_sockets > ARRAY_SIZE(new_ids)))
 		return -ENXIO;
 
-	pci_set_power_state(dev, PCI_D0);
-	pci_restore_state(dev);
-	rc = pci_enable_device(dev);
-	if (rc)
-		return rc;
 	pci_set_master(dev);
 
 	dev_dbg(&dev->dev, "resuming host\n");
@@ -297,13 +289,6 @@ static int tifm_7xx1_resume(struct pci_dev *dev)
 	return 0;
 }
 
-#else
-
-#define tifm_7xx1_suspend NULL
-#define tifm_7xx1_resume NULL
-
-#endif /* CONFIG_PM */
-
 static int tifm_7xx1_dummy_has_ms_pif(struct tifm_adapter *fm,
 				      struct tifm_dev *sock)
 {
@@ -424,13 +409,14 @@ static const struct pci_device_id tifm_7xx1_pci_tbl[] = {
 	{ }
 };
 
+static SIMPLE_DEV_PM_OPS(tifm_7xx1_pm_ops, tifm_7xx1_suspend, tifm_7xx1_resume);
+
 static struct pci_driver tifm_7xx1_driver = {
 	.name = DRIVER_NAME,
 	.id_table = tifm_7xx1_pci_tbl,
 	.probe = tifm_7xx1_probe,
 	.remove = tifm_7xx1_remove,
-	.suspend = tifm_7xx1_suspend,
-	.resume = tifm_7xx1_resume,
+	.driver.pm = &tifm_7xx1_pm_ops,
 };
 
 module_pci_driver(tifm_7xx1_driver);