[Linux-kernel-mentees] [PATCH v2 05/15] scsi: arcmsr: use generic power management

[Vaibhav Gupta]

With legacy PM hooks, it was the responsibility of a driver to manage PCI
states and also the device's power state. The generic approach is to let
the PCI core handle the work.

PCI core passes "struct device*" as an argument to the .suspend() and
.resume() callbacks.

Driver was also using PCI helper functions like pci_save/restore_state(),
pci_disable/enable_device(), pci_set_power_state() and pci_enable_wake().
They should not be invoked by the driver.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/scsi/arcmsr/arcmsr_hba.c | 35 ++++++++++++--------------------
 1 file changed, 13 insertions(+), 22 deletions(-)

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 30914c8f29cc..7e098ddcc4f5 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -113,8 +113,8 @@ static int arcmsr_bios_param(struct scsi_device *sdev,
 static int arcmsr_queue_command(struct Scsi_Host *h, struct scsi_cmnd *cmd);
 static int arcmsr_probe(struct pci_dev *pdev,
 				const struct pci_device_id *id);
-static int arcmsr_suspend(struct pci_dev *pdev, pm_message_t state);
-static int arcmsr_resume(struct pci_dev *pdev);
+static int __maybe_unused arcmsr_suspend(struct device *dev);
+static int __maybe_unused arcmsr_resume(struct device *dev);
 static void arcmsr_remove(struct pci_dev *pdev);
 static void arcmsr_shutdown(struct pci_dev *pdev);
 static void arcmsr_iop_init(struct AdapterControlBlock *acb);
@@ -213,13 +213,14 @@ static struct pci_device_id arcmsr_device_id_table[] = {
 };
 MODULE_DEVICE_TABLE(pci, arcmsr_device_id_table);
 
+static SIMPLE_DEV_PM_OPS(arcmsr_pm_ops, arcmsr_suspend, arcmsr_resume);
+
 static struct pci_driver arcmsr_pci_driver = {
 	.name			= "arcmsr",
 	.id_table		= arcmsr_device_id_table,
 	.probe			= arcmsr_probe,
 	.remove			= arcmsr_remove,
-	.suspend		= arcmsr_suspend,
-	.resume			= arcmsr_resume,
+	.driver.pm		= &arcmsr_pm_ops,
 	.shutdown		= arcmsr_shutdown,
 };
 /*
@@ -1065,14 +1066,14 @@ static void arcmsr_free_irq(struct pci_dev *pdev,
 	pci_free_irq_vectors(pdev);
 }
 
-static int arcmsr_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused arcmsr_suspend(struct device *dev)
 {
-	uint32_t intmask_org;
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct Scsi_Host *host = pci_get_drvdata(pdev);
 	struct AdapterControlBlock *acb =
 		(struct AdapterControlBlock *)host->hostdata;
 
-	intmask_org = arcmsr_disable_outbound_ints(acb);
+	arcmsr_disable_outbound_ints(acb);
 	arcmsr_free_irq(pdev, acb);
 	del_timer_sync(&acb->eternal_timer);
 	if (set_date_time)
@@ -1080,29 +1081,21 @@ static int arcmsr_suspend(struct pci_dev *pdev, pm_message_t state)
 	flush_work(&acb->arcmsr_do_message_isr_bh);
 	arcmsr_stop_adapter_bgrb(acb);
 	arcmsr_flush_adapter_cache(acb);
-	pci_set_drvdata(pdev, host);
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, pci_choose_state(pdev, state));
 	return 0;
 }
 
-static int arcmsr_resume(struct pci_dev *pdev)
+static int __maybe_unused arcmsr_resume(struct device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev);
 	struct Scsi_Host *host = pci_get_drvdata(pdev);
 	struct AdapterControlBlock *acb =
 		(struct AdapterControlBlock *)host->hostdata;
 
-	pci_set_power_state(pdev, PCI_D0);
-	pci_enable_wake(pdev, PCI_D0, 0);
-	pci_restore_state(pdev);
-	if (pci_enable_device(pdev)) {
-		pr_warn("%s: pci_enable_device error\n", __func__);
-		return -ENODEV;
-	}
+	device_wakeup_disable(dev);
+
 	if (arcmsr_set_dma_mask(acb))
 		goto controller_unregister;
-	pci_set_master(pdev);
+
 	if (arcmsr_request_irq(pdev, acb) == FAILED)
 		goto controller_stop;
 	switch (acb->adapter_type) {
@@ -1137,9 +1130,7 @@ static int arcmsr_resume(struct pci_dev *pdev)
 	scsi_remove_host(host);
 	arcmsr_free_ccb_pool(acb);
 	arcmsr_unmap_pciregion(acb);
-	pci_release_regions(pdev);
 	scsi_host_put(host);
-	pci_disable_device(pdev);
 	return -ENODEV;
 }
 
-- 
2.27.0