[Linux-kernel-mentees] [PATCH v1 04/15] scsi: aic79xx: use generic power management

Vaibhav Gupta vaibhavgupta40 at gmail.com
Fri Jul 17 06:34:27 UTC 2020


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 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.

Also, .suspend() and .resume() were invoking other functions for PM, which
were againg bounded by "#ifdef CONFIG_PM" directive. Remove them and mark
them as "__maybe_unused".

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/scsi/aic7xxx/aic79xx.h         | 12 +++----
 drivers/scsi/aic7xxx/aic79xx_core.c    |  8 ++---
 drivers/scsi/aic7xxx/aic79xx_osm_pci.c | 43 +++++++-------------------
 drivers/scsi/aic7xxx/aic79xx_pci.c     |  6 ++--
 4 files changed, 20 insertions(+), 49 deletions(-)

diff --git a/drivers/scsi/aic7xxx/aic79xx.h b/drivers/scsi/aic7xxx/aic79xx.h
index 9a515551641c..dd5dfd4f30a5 100644
--- a/drivers/scsi/aic7xxx/aic79xx.h
+++ b/drivers/scsi/aic7xxx/aic79xx.h
@@ -1330,10 +1330,8 @@ const struct	ahd_pci_identity *ahd_find_pci_device(ahd_dev_softc_t);
 int			  ahd_pci_config(struct ahd_softc *,
 					 const struct ahd_pci_identity *);
 int	ahd_pci_test_register_access(struct ahd_softc *);
-#ifdef CONFIG_PM
-void	ahd_pci_suspend(struct ahd_softc *);
-void	ahd_pci_resume(struct ahd_softc *);
-#endif
+void __maybe_unused	ahd_pci_suspend(struct ahd_softc *);
+void __maybe_unused	ahd_pci_resume(struct ahd_softc *);
 
 /************************** SCB and SCB queue management **********************/
 void		ahd_qinfifo_requeue_tail(struct ahd_softc *ahd,
@@ -1344,10 +1342,8 @@ struct ahd_softc	*ahd_alloc(void *platform_arg, char *name);
 int			 ahd_softc_init(struct ahd_softc *);
 void			 ahd_controller_info(struct ahd_softc *ahd, char *buf);
 int			 ahd_init(struct ahd_softc *ahd);
-#ifdef CONFIG_PM
-int			 ahd_suspend(struct ahd_softc *ahd);
-void			 ahd_resume(struct ahd_softc *ahd);
-#endif
+int __maybe_unused	 ahd_suspend(struct ahd_softc *ahd);
+void __maybe_unused	 ahd_resume(struct ahd_softc *ahd);
 int			 ahd_default_config(struct ahd_softc *ahd);
 int			 ahd_parse_vpddata(struct ahd_softc *ahd,
 					   struct vpd_config *vpd);
diff --git a/drivers/scsi/aic7xxx/aic79xx_core.c b/drivers/scsi/aic7xxx/aic79xx_core.c
index e4a09b93d00c..06ee7abd0f8f 100644
--- a/drivers/scsi/aic7xxx/aic79xx_core.c
+++ b/drivers/scsi/aic7xxx/aic79xx_core.c
@@ -7880,11 +7880,9 @@ ahd_pause_and_flushwork(struct ahd_softc *ahd)
 	ahd->flags &= ~AHD_ALL_INTERRUPTS;
 }
 
-#ifdef CONFIG_PM
-int
+int __maybe_unused
 ahd_suspend(struct ahd_softc *ahd)
 {
-
 	ahd_pause_and_flushwork(ahd);
 
 	if (LIST_FIRST(&ahd->pending_scbs) != NULL) {
@@ -7895,15 +7893,13 @@ ahd_suspend(struct ahd_softc *ahd)
 	return (0);
 }
 
-void
+void __maybe_unused
 ahd_resume(struct ahd_softc *ahd)
 {
-
 	ahd_reset(ahd, /*reinit*/TRUE);
 	ahd_intr_enable(ahd, TRUE); 
 	ahd_restart(ahd);
 }
-#endif
 
 /************************** Busy Target Table *********************************/
 /*
diff --git a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
index 8b891a05d9e7..07b670b80f1b 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
+++ b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
@@ -74,11 +74,10 @@ static const struct pci_device_id ahd_linux_pci_id_table[] = {
 
 MODULE_DEVICE_TABLE(pci, ahd_linux_pci_id_table);
 
-#ifdef CONFIG_PM
-static int
-ahd_linux_pci_dev_suspend(struct pci_dev *pdev, pm_message_t mesg)
+static int __maybe_unused
+ahd_linux_pci_dev_suspend(struct device *dev)
 {
-	struct ahd_softc *ahd = pci_get_drvdata(pdev);
+	struct ahd_softc *ahd = dev_get_drvdata(dev);
 	int rc;
 
 	if ((rc = ahd_suspend(ahd)))
@@ -86,39 +85,20 @@ ahd_linux_pci_dev_suspend(struct pci_dev *pdev, pm_message_t mesg)
 
 	ahd_pci_suspend(ahd);
 
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-
-	if (mesg.event & PM_EVENT_SLEEP)
-		pci_set_power_state(pdev, PCI_D3hot);
-
 	return rc;
 }
 
-static int
-ahd_linux_pci_dev_resume(struct pci_dev *pdev)
+static int __maybe_unused
+ahd_linux_pci_dev_resume(struct device *dev)
 {
-	struct ahd_softc *ahd = 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 ahd_softc *ahd = dev_get_drvdata(dev);
 
 	ahd_pci_resume(ahd);
 
 	ahd_resume(ahd);
 
-	return rc;
+	return 0;
 }
-#endif
 
 static void
 ahd_linux_pci_dev_remove(struct pci_dev *pdev)
@@ -224,13 +204,14 @@ ahd_linux_pci_dev_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	return (0);
 }
 
+static SIMPLE_DEV_PM_OPS(ahd_linux_pci_dev_pm_ops,
+			 ahd_linux_pci_dev_suspend,
+			 ahd_linux_pci_dev_resume);
+
 static struct pci_driver aic79xx_pci_driver = {
 	.name		= "aic79xx",
 	.probe		= ahd_linux_pci_dev_probe,
-#ifdef CONFIG_PM
-	.suspend	= ahd_linux_pci_dev_suspend,
-	.resume		= ahd_linux_pci_dev_resume,
-#endif
+	.driver.pm	= &ahd_linux_pci_dev_pm_ops,
 	.remove		= ahd_linux_pci_dev_remove,
 	.id_table	= ahd_linux_pci_id_table
 };
diff --git a/drivers/scsi/aic7xxx/aic79xx_pci.c b/drivers/scsi/aic7xxx/aic79xx_pci.c
index 8397ae93f7dd..2f0bdb9225a4 100644
--- a/drivers/scsi/aic7xxx/aic79xx_pci.c
+++ b/drivers/scsi/aic7xxx/aic79xx_pci.c
@@ -377,8 +377,7 @@ ahd_pci_config(struct ahd_softc *ahd, const struct ahd_pci_identity *entry)
 	return ahd_pci_map_int(ahd);
 }
 
-#ifdef CONFIG_PM
-void
+void __maybe_unused
 ahd_pci_suspend(struct ahd_softc *ahd)
 {
 	/*
@@ -394,7 +393,7 @@ ahd_pci_suspend(struct ahd_softc *ahd)
 
 }
 
-void
+void __maybe_unused
 ahd_pci_resume(struct ahd_softc *ahd)
 {
 	ahd_pci_write_config(ahd->dev_softc, DEVCONFIG,
@@ -404,7 +403,6 @@ ahd_pci_resume(struct ahd_softc *ahd)
 	ahd_pci_write_config(ahd->dev_softc, CSIZE_LATTIME,
 			     ahd->suspend_state.pci_state.csize_lattime, /*bytes*/1);
 }
-#endif
 
 /*
  * Perform some simple tests that should catch situations where
-- 
2.27.0



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