cb710/core.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.

Compile-tested only.
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Link: https://lore.kernel.org/r/20200629081531.214734-2-vaibhavgupta40@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/cb710/core.c

@@ -166,37 +166,24 @@ void cb710_set_irq_handler(struct cb710_slot *slot,
 }
 EXPORT_SYMBOL_GPL(cb710_set_irq_handler);
 
-#ifdef CONFIG_PM
-
-static int cb710_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused cb710_suspend(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct cb710_chip *chip = pci_get_drvdata(pdev);
 
 	devm_free_irq(&pdev->dev, pdev->irq, chip);
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	if (state.event & PM_EVENT_SLEEP)
-		pci_set_power_state(pdev, PCI_D3hot);
 	return 0;
 }
 
-static int cb710_resume(struct pci_dev *pdev)
+static int __maybe_unused cb710_resume(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct cb710_chip *chip = pci_get_drvdata(pdev);
-	int err;
-
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-	err = pcim_enable_device(pdev);
-	if (err)
-		return err;
 
 	return devm_request_irq(&pdev->dev, pdev->irq,
 		cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
 }
 
-#endif /* CONFIG_PM */
-
 static int cb710_probe(struct pci_dev *pdev,
 	const struct pci_device_id *ent)
 {
@@ -312,15 +299,14 @@ static const struct pci_device_id cb710_pci_tbl[] = {
 	{ 0, }
 };
 
+static SIMPLE_DEV_PM_OPS(cb710_pm_ops, cb710_suspend, cb710_resume);
+
 static struct pci_driver cb710_driver = {
 	.name = KBUILD_MODNAME,
 	.id_table = cb710_pci_tbl,
 	.probe = cb710_probe,
 	.remove = cb710_remove_one,
-#ifdef CONFIG_PM
-	.suspend = cb710_suspend,
-	.resume = cb710_resume,
-#endif
+	.driver.pm = &cb710_pm_ops,
 };
 
 static int __init cb710_init_module(void)