[Linux-kernel-mentees] [PATCH v1 4/5] tulip: tulip_core: use generic power management

[Vaibhav Gupta]

With the support of generic PM callbacks, drivers no longer need to use
legacy .suspend() and .resume() in which they had to maintain PCI
states changes and device's power state themselves.

Earlier, .suspend() and .resume() were invoking pci_disable_device()
and pci_enable_device() respectively to manage the device's power state.
driver also invoked pci_save/restore_state() and pci_set_power_sitate().
With generic PM, it is no longer needed. The driver is expected to just
implement driver-specific operations and leave power transitions to PCI
core.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/net/ethernet/dec/tulip/tulip_core.c | 51 +++++----------------
 1 file changed, 12 insertions(+), 39 deletions(-)

diff --git a/drivers/net/ethernet/dec/tulip/tulip_core.c b/drivers/net/ethernet/dec/tulip/tulip_core.c
index 15efc294f513..9db23527275a 100644
--- a/drivers/net/ethernet/dec/tulip/tulip_core.c
+++ b/drivers/net/ethernet/dec/tulip/tulip_core.c
@@ -1803,13 +1803,9 @@ static void tulip_set_wolopts (struct pci_dev *pdev, u32 wolopts)
 	}
 }
 
-#ifdef CONFIG_PM
-
-
-static int tulip_suspend (struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused tulip_suspend(struct device *dev_d)
 {
-	pci_power_t pstate;
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct net_device *dev = dev_get_drvdata(dev_d);
 	struct tulip_private *tp = netdev_priv(dev);
 
 	if (!dev)
@@ -1825,45 +1821,27 @@ static int tulip_suspend (struct pci_dev *pdev, pm_message_t state)
 	free_irq(tp->pdev->irq, dev);
 
 save_state:
-	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pstate = pci_choose_state(pdev, state);
-	if (state.event == PM_EVENT_SUSPEND && pstate != PCI_D0) {
-		int rc;
-
-		tulip_set_wolopts(pdev, tp->wolinfo.wolopts);
-		rc = pci_enable_wake(pdev, pstate, tp->wolinfo.wolopts);
-		if (rc)
-			pr_err("pci_enable_wake failed (%d)\n", rc);
-	}
-	pci_set_power_state(pdev, pstate);
+	tulip_set_wolopts(to_pci_dev(dev_d), tp->wolinfo.wolopts);
+	device_set_wakeup_enable(dev_d, !!tp->wolinfo.wolopts);
 
 	return 0;
 }
 
-
-static int tulip_resume(struct pci_dev *pdev)
+static int __maybe_unused tulip_resume(struct device *dev_d)
 {
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct pci_dev *pdev = to_pci_dev(dev_d);
+	struct net_device *dev = dev_get_drvdata(dev_d);
 	struct tulip_private *tp = netdev_priv(dev);
 	void __iomem *ioaddr = tp->base_addr;
-	int retval;
 	unsigned int tmp;
+	int retval = 0;
 
 	if (!dev)
 		return -EINVAL;
 
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-
 	if (!netif_running(dev))
 		return 0;
 
-	if ((retval = pci_enable_device(pdev))) {
-		pr_err("pci_enable_device failed in resume\n");
-		return retval;
-	}
-
 	retval = request_irq(pdev->irq, tulip_interrupt, IRQF_SHARED,
 			     dev->name, dev);
 	if (retval) {
@@ -1872,8 +1850,7 @@ static int tulip_resume(struct pci_dev *pdev)
 	}
 
 	if (tp->flags & COMET_PM) {
-		pci_enable_wake(pdev, PCI_D3hot, 0);
-		pci_enable_wake(pdev, PCI_D3cold, 0);
+		device_set_wakeup_enable(dev_d, 0);
 
 		/* Clear the PMES flag */
 		tmp = ioread32(ioaddr + CSR20);
@@ -1891,9 +1868,6 @@ static int tulip_resume(struct pci_dev *pdev)
 	return 0;
 }
 
-#endif /* CONFIG_PM */
-
-
 static void tulip_remove_one(struct pci_dev *pdev)
 {
 	struct net_device *dev = pci_get_drvdata (pdev);
@@ -1937,15 +1911,14 @@ static void poll_tulip (struct net_device *dev)
 }
 #endif
 
+static SIMPLE_DEV_PM_OPS(tulip_pm_ops, tulip_suspend, tulip_resume);
+
 static struct pci_driver tulip_driver = {
 	.name		= DRV_NAME,
 	.id_table	= tulip_pci_tbl,
 	.probe		= tulip_init_one,
 	.remove		= tulip_remove_one,
-#ifdef CONFIG_PM
-	.suspend	= tulip_suspend,
-	.resume		= tulip_resume,
-#endif /* CONFIG_PM */
+	.driver.pm	= &tulip_pm_ops,
 };
 
 
-- 
2.27.0