scsi: mvumi: 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/20201102164730.324035-27-vaibhavgupta40@gmail.comSigned-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/mvumi.c

@@ -2567,46 +2567,26 @@ static void mvumi_shutdown(struct pci_dev *pdev)
 	mvumi_flush_cache(mhba);
 }
 
-static int __maybe_unused mvumi_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused mvumi_suspend(struct device *dev)
 {
-	struct mvumi_hba *mhba = NULL;
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct mvumi_hba *mhba = pci_get_drvdata(pdev);
 
-	mhba = pci_get_drvdata(pdev);
 	mvumi_flush_cache(mhba);
 
-	pci_set_drvdata(pdev, mhba);
 	mhba->instancet->disable_intr(mhba);
-	free_irq(mhba->pdev->irq, mhba);
 	mvumi_unmap_pci_addr(pdev, mhba->base_addr);
-	pci_release_regions(pdev);
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
 
 	return 0;
 }
 
-static int __maybe_unused mvumi_resume(struct pci_dev *pdev)
+static int __maybe_unused mvumi_resume(struct device *dev)
 {
 	int ret;
-	struct mvumi_hba *mhba = NULL;
-
-	mhba = pci_get_drvdata(pdev);
-
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-
-	ret = pci_enable_device(pdev);
-	if (ret) {
-		dev_err(&pdev->dev, "enable device failed\n");
-		return ret;
-	}
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct mvumi_hba *mhba = pci_get_drvdata(pdev);
 
-	ret = mvumi_pci_set_master(pdev);
 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
-	if (ret)
-		goto fail;
-	ret = pci_request_regions(mhba->pdev, MV_DRIVER_NAME);
 	if (ret)
 		goto fail;
 	ret = mvumi_map_pci_addr(mhba->pdev, mhba->base_addr);
@@ -2626,12 +2606,6 @@ static int __maybe_unused mvumi_resume(struct pci_dev *pdev)
 		goto unmap_pci_addr;
 	}
 
-	ret = request_irq(mhba->pdev->irq, mvumi_isr_handler, IRQF_SHARED,
-				"mvumi", mhba);
-	if (ret) {
-		dev_err(&pdev->dev, "failed to register IRQ\n");
-		goto unmap_pci_addr;
-	}
 	mhba->instancet->enable_intr(mhba);
 
 	return 0;
@@ -2641,11 +2615,12 @@ static int __maybe_unused mvumi_resume(struct pci_dev *pdev)
 release_regions:
 	pci_release_regions(pdev);
 fail:
-	pci_disable_device(pdev);
 
 	return ret;
 }
 
+static SIMPLE_DEV_PM_OPS(mvumi_pm_ops, mvumi_suspend, mvumi_resume);
+
 static struct pci_driver mvumi_pci_driver = {
 
 	.name = MV_DRIVER_NAME,
@@ -2653,10 +2628,7 @@ static struct pci_driver mvumi_pci_driver = {
 	.probe = mvumi_probe_one,
 	.remove = mvumi_detach_one,
 	.shutdown = mvumi_shutdown,
-#ifdef CONFIG_PM
-	.suspend = mvumi_suspend,
-	.resume = mvumi_resume,
-#endif
+	.driver.pm = &mvumi_pm_ops,
 };
 
 module_pci_driver(mvumi_pci_driver);