[PATCH v3] driver: gpio-bt8xx: use generic PCI PM

[Vaibhav Gupta <vaibhavgupta40@gmail.com>]

Switch to the new generic PCI power management framework and remove legacy
callbacks like .suspend() and .resume(). With the generic framework, the
standard PCI related work like:
	- pci_save/restore_state()
	- pci_enable/disable_device()
	- pci_set_power_state()
is handled by the PCI core and this driver should implement only gpio-bt8xx
specific operations in its respective callback functions.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
---
 drivers/gpio/gpio-bt8xx.c | 29 +++++++----------------------
 1 file changed, 7 insertions(+), 22 deletions(-)

diff --git a/drivers/gpio/gpio-bt8xx.c b/drivers/gpio/gpio-bt8xx.c
index 05401da03ca3..70b49c385b43 100644
--- a/drivers/gpio/gpio-bt8xx.c
+++ b/drivers/gpio/gpio-bt8xx.c
@@ -52,10 +52,8 @@ struct bt8xxgpio {
 	struct pci_dev *pdev;
 	struct gpio_chip gpio;
 
-#ifdef CONFIG_PM
 	u32 saved_outen;
 	u32 saved_data;
-#endif
 };
 
 #define bgwrite(dat, adr)	writel((dat), bg->mmio+(adr))
@@ -224,9 +222,9 @@ static void bt8xxgpio_remove(struct pci_dev *pdev)
 	pci_disable_device(pdev);
 }
 
-#ifdef CONFIG_PM
-static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused bt8xxgpio_suspend(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
 
 	scoped_guard(spinlock_irqsave, &bg->lock) {
@@ -238,23 +236,13 @@ static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
 		bgwrite(0x0, BT848_GPIO_OUT_EN);
 	}
 
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
-
 	return 0;
 }
 
-static int bt8xxgpio_resume(struct pci_dev *pdev)
+static int __maybe_unused bt8xxgpio_resume(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
-	int err;
-
-	pci_set_power_state(pdev, PCI_D0);
-	err = pci_enable_device(pdev);
-	if (err)
-		return err;
-	pci_restore_state(pdev);
 
 	guard(spinlock_irqsave)(&bg->lock);
 
@@ -267,10 +255,8 @@ static int bt8xxgpio_resume(struct pci_dev *pdev)
 
 	return 0;
 }
-#else
-#define bt8xxgpio_suspend NULL
-#define bt8xxgpio_resume NULL
-#endif /* CONFIG_PM */
+
+static DEFINE_SIMPLE_DEV_PM_OPS(bt8xxgpio_pm_ops, bt8xxgpio_suspend, bt8xxgpio_resume);
 
 static const struct pci_device_id bt8xxgpio_pci_tbl[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT848) },
@@ -286,8 +272,7 @@ static struct pci_driver bt8xxgpio_pci_driver = {
 	.id_table	= bt8xxgpio_pci_tbl,
 	.probe		= bt8xxgpio_probe,
 	.remove		= bt8xxgpio_remove,
-	.suspend	= bt8xxgpio_suspend,
-	.resume		= bt8xxgpio_resume,
+	.driver.pm	= &bt8xxgpio_pm_ops,
 };
 
 module_pci_driver(bt8xxgpio_pci_driver);
-- 
2.51.0