[Linux-kernel-mentees] [PATCH v1 07/15] scsi: hisi_sas_v3_hw: use generic power management

[Vaibhav Gupta]

With legacy PM, drivers themselves were responsible for managing the
device's power states and takes care of register states.

After upgrading to the generic structure, PCI core will take care of
required tasks and drivers should do only device-specific operations.

The driver was calling pci_save/restore_state(), pci_choose_state(),
pci_enable/disable_device() and pci_set_power_state() which is no more
needed.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 32 ++++++++------------------
 1 file changed, 10 insertions(+), 22 deletions(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index 55e2321a65bc..45605a520bc8 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -3374,13 +3374,13 @@ enum {
 	hip08,
 };
 
-static int hisi_sas_v3_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused hisi_sas_v3_suspend(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct sas_ha_struct *sha = pci_get_drvdata(pdev);
 	struct hisi_hba *hisi_hba = sha->lldd_ha;
 	struct device *dev = hisi_hba->dev;
 	struct Scsi_Host *shost = hisi_hba->shost;
-	pci_power_t device_state;
 	int rc;
 
 	if (!pdev->pm_cap) {
@@ -3406,21 +3406,15 @@ static int hisi_sas_v3_suspend(struct pci_dev *pdev, pm_message_t state)
 
 	hisi_sas_init_mem(hisi_hba);
 
-	device_state = pci_choose_state(pdev, state);
-	dev_warn(dev, "entering operating state [D%d]\n",
-			device_state);
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, device_state);
-
 	hisi_sas_release_tasks(hisi_hba);
 
 	sas_suspend_ha(sha);
 	return 0;
 }
 
-static int hisi_sas_v3_resume(struct pci_dev *pdev)
+static int __maybe_unused hisi_sas_v3_resume(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct sas_ha_struct *sha = pci_get_drvdata(pdev);
 	struct hisi_hba *hisi_hba = sha->lldd_ha;
 	struct Scsi_Host *shost = hisi_hba->shost;
@@ -3430,16 +3424,8 @@ static int hisi_sas_v3_resume(struct pci_dev *pdev)
 
 	dev_warn(dev, "resuming from operating state [D%d]\n",
 		 device_state);
-	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(dev, "enable device failed during resume (%d)\n", rc);
-		return rc;
-	}
+	device_wakeup_disable(dev_d);
 
-	pci_set_master(pdev);
 	scsi_unblock_requests(shost);
 	clear_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
 
@@ -3447,7 +3433,6 @@ static int hisi_sas_v3_resume(struct pci_dev *pdev)
 	rc = hw_init_v3_hw(hisi_hba);
 	if (rc) {
 		scsi_remove_host(shost);
-		pci_disable_device(pdev);
 		return rc;
 	}
 	hisi_hba->hw->phys_init(hisi_hba);
@@ -3468,13 +3453,16 @@ static const struct pci_error_handlers hisi_sas_err_handler = {
 	.reset_done	= hisi_sas_reset_done_v3_hw,
 };
 
+static SIMPLE_DEV_PM_OPS(hisi_sas_v3_pm_ops,
+			 hisi_sas_v3_suspend,
+			 hisi_sas_v3_resume);
+
 static struct pci_driver sas_v3_pci_driver = {
 	.name		= DRV_NAME,
 	.id_table	= sas_v3_pci_table,
 	.probe		= hisi_sas_v3_probe,
 	.remove		= hisi_sas_v3_remove,
-	.suspend	= hisi_sas_v3_suspend,
-	.resume		= hisi_sas_v3_resume,
+	.driver.pm	= &hisi_sas_v3_pm_ops,
 	.err_handler	= &hisi_sas_err_handler,
 };
 
-- 
2.27.0