[PATCH v2 15/15] scsi: pmcraid: use generic power management

[Vaibhav Gupta <vaibhavgupta40@gmail.com>]

Drivers using legacy PM have to manage PCI states and device's PM states
themselves. They also need to take care of configuration registers.

With improved and powerful support of generic PM, PCI Core takes care of
above mentioned, device-independent, jobs.

This driver makes use of PCI helper functions like
pci_save/restore_state(), pci_enable/disable_device(),
pci_set_power_state() and to do required operations. In generic mode, they
are no longer needed.

Change function parameter in both .suspend() and .resume() to
"struct device*" type. Use to_pci_dev() to get "struct pci_dev*" variable.

In function pmcraid_resume(), earlier, the variable "rc" was set by
pci_enable_device() which is now removed. Since PCI core does the required
job, initialize "rc" with 0 value when declaring it.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
---
 drivers/scsi/pmcraid.c | 44 +++++++++++-------------------------------
 1 file changed, 11 insertions(+), 33 deletions(-)

diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index aa9ae2ae8579..b6b70ac2e2ee 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -5237,54 +5237,39 @@ static void pmcraid_remove(struct pci_dev *pdev)
 	return;
 }
 
-#ifdef CONFIG_PM
 /**
  * pmcraid_suspend - driver suspend entry point for power management
- * @pdev:   PCI device structure
- * @state:  PCI power state to suspend routine
+ * @dev:   Device structure
  *
  * Return Value - 0 always
  */
-static int pmcraid_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused pmcraid_suspend(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
 
 	pmcraid_shutdown(pdev);
 	pmcraid_disable_interrupts(pinstance, ~0);
 	pmcraid_kill_tasklets(pinstance);
-	pci_set_drvdata(pinstance->pdev, pinstance);
 	pmcraid_unregister_interrupt_handler(pinstance);
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
 
 	return 0;
 }
 
 /**
  * pmcraid_resume - driver resume entry point PCI power management
- * @pdev: PCI device structure
+ * @dev: Device structure
  *
  * Return Value - 0 in case of success. Error code in case of any failure
  */
-static int pmcraid_resume(struct pci_dev *pdev)
+static int __maybe_unused pmcraid_resume(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
 	struct Scsi_Host *host = pinstance->host;
-	int rc;
-
-	pci_set_power_state(pdev, PCI_D0);
-	pci_enable_wake(pdev, PCI_D0, 0);
-	pci_restore_state(pdev);
-
-	rc = pci_enable_device(pdev);
-
-	if (rc) {
-		dev_err(&pdev->dev, "resume: Enable device failed\n");
-		return rc;
-	}
+	int rc = 0;
 
-	pci_set_master(pdev);
+	device_wakeup_disable(dev);
 
 	if (sizeof(dma_addr_t) == 4 ||
 	    dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)))
@@ -5337,18 +5322,10 @@ static int pmcraid_resume(struct pci_dev *pdev)
 	scsi_host_put(host);
 
 disable_device:
-	pci_disable_device(pdev);
 
 	return rc;
 }
 
-#else
-
-#define pmcraid_suspend NULL
-#define pmcraid_resume  NULL
-
-#endif /* CONFIG_PM */
-
 /**
  * pmcraid_complete_ioa_reset - Called by either timer or tasklet during
  *				completion of the ioa reset
@@ -5836,6 +5813,8 @@ static int pmcraid_probe(struct pci_dev *pdev,
 	return -ENODEV;
 }
 
+static SIMPLE_DEV_PM_OPS(pmcraid_pm_ops, pmcraid_suspend, pmcraid_resume);
+
 /*
  * PCI driver structure of pmcraid driver
  */
@@ -5844,8 +5823,7 @@ static struct pci_driver pmcraid_driver = {
 	.id_table = pmcraid_pci_table,
 	.probe = pmcraid_probe,
 	.remove = pmcraid_remove,
-	.suspend = pmcraid_suspend,
-	.resume = pmcraid_resume,
+	.driver.pm = &pmcraid_pm_ops,
 	.shutdown = pmcraid_shutdown
 };
 
-- 
2.27.0