scsi: aic7xxx: Use generic power management

Drivers should do only device-specific jobs. But in general, drivers using
legacy PCI PM framework for .suspend()/.resume() have to manage many PCI
PM-related tasks themselves which can be done by PCI Core itself. This
brings extra load on the driver and it directly calls PCI helper functions
to handle them.

Switch to the new generic framework by updating function signatures and
define a "struct dev_pm_ops" variable to bind PM callbacks. Also, remove
unnecessary calls to the PCI Helper functions along with the legacy
.suspend & .resume bindings.

Link: https://lore.kernel.org/r/20201102164730.324035-7-vaibhavgupta40@gmail.com
Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 11 insertions, 35 deletions

diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
index 9b293b1f0b71..a07e94fac673 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm_pci.c
@@ -121,47 +121,23 @@ static const struct pci_device_id ahc_linux_pci_id_table[] = {
 
 MODULE_DEVICE_TABLE(pci, ahc_linux_pci_id_table);
 
-#ifdef CONFIG_PM
-static int
-ahc_linux_pci_dev_suspend(struct pci_dev *pdev, pm_message_t mesg)
+static int __maybe_unused
+ahc_linux_pci_dev_suspend(struct device *dev)
 {
-	struct ahc_softc *ahc = pci_get_drvdata(pdev);
-	int rc;
-
-	if ((rc = ahc_suspend(ahc)))
-		return rc;
+	struct ahc_softc *ahc = dev_get_drvdata(dev);
 
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-
-	if (mesg.event & PM_EVENT_SLEEP)
-		pci_set_power_state(pdev, PCI_D3hot);
-
-	return rc;
+	return ahc_suspend(ahc);
 }
 
-static int
-ahc_linux_pci_dev_resume(struct pci_dev *pdev)
+static int __maybe_unused
+ahc_linux_pci_dev_resume(struct device *dev)
 {
-	struct ahc_softc *ahc = pci_get_drvdata(pdev);
-	int rc;
-
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-
-	if ((rc = pci_enable_device(pdev))) {
-		dev_printk(KERN_ERR, &pdev->dev,
-			   "failed to enable device after resume (%d)\n", rc);
-		return rc;
-	}
-
-	pci_set_master(pdev);
+	struct ahc_softc *ahc = dev_get_drvdata(dev);
 
 	ahc_pci_resume(ahc);
 
 	return (ahc_resume(ahc));
 }
-#endif
 
 static void
 ahc_linux_pci_dev_remove(struct pci_dev *pdev)
@@ -319,14 +295,14 @@ ahc_pci_write_config(ahc_dev_softc_t pci, int reg, uint32_t value, int width)
 	}
 }
 
+static SIMPLE_DEV_PM_OPS(ahc_linux_pci_dev_pm_ops,
+			 ahc_linux_pci_dev_suspend,
+			 ahc_linux_pci_dev_resume);
 
 static struct pci_driver aic7xxx_pci_driver = {
 	.name		= "aic7xxx",
 	.probe		= ahc_linux_pci_dev_probe,
-#ifdef CONFIG_PM
-	.suspend	= ahc_linux_pci_dev_suspend,
-	.resume		= ahc_linux_pci_dev_resume,
-#endif
+	.driver.pm	= &ahc_linux_pci_dev_pm_ops,
 	.remove		= ahc_linux_pci_dev_remove,
 	.id_table	= ahc_linux_pci_id_table
 };