[Linux-kernel-mentees] [PATCH v1 01/11] typhoon: use generic power management

Vaibhav Gupta vaibhavgupta40 at gmail.com
Wed Jul 1 12:59:28 UTC 2020


With legacy PM, drivers themselves were responsible for managing the
device's power states and takes care of register states. And they use PCI
helper functions to do it.

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

In this driver:
typhoon_resume() calls typhoon_wakeup() which then calls PCI helper
functions pci_set_power_state() and pci_restore_state(). The only other
function, using typhoon_wakeup() is typhoon_open().

Thus remove the pci_*() calls from tyhpoon_wakeup() and place them in
typhoon_open(), maintaining the order, to retain the normal behavior of
the function

Now, typhoon_suspend() calls typhoon_sleep() which then calls PCI helper
functions pci_enable_wake(), pci_disable_device() and
pci_set_power_state(). Other functions:
 - typhoon_open()
 - typhoon_close()
 - typhoon_init_one()
are also invoking typhoon_sleep(). Thus, in this case, cannot simply
move PCI helper functions call.

Hence, define a new function typhoon_sleep_early() which will do all the
operations, which typhoon_sleep() was doing before calling PCI helper
functions. Now typhoon_sleep() will call typhoon_sleep_early() to do
those tasks, hence, the behavior for _open(), _close and _init_one() remain
unchanged. And typhon_suspend() only requires typhoon_sleep_early().

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/net/ethernet/3com/typhoon.c | 53 +++++++++++++++++------------
 1 file changed, 32 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/3com/typhoon.c b/drivers/net/ethernet/3com/typhoon.c
index 5ed33c2c4742..d3b30bacc94e 100644
--- a/drivers/net/ethernet/3com/typhoon.c
+++ b/drivers/net/ethernet/3com/typhoon.c
@@ -1801,9 +1801,8 @@ typhoon_free_rx_rings(struct typhoon *tp)
 }
 
 static int
-typhoon_sleep(struct typhoon *tp, pci_power_t state, __le16 events)
+typhoon_sleep_early(struct typhoon *tp, __le16 events)
 {
-	struct pci_dev *pdev = tp->pdev;
 	void __iomem *ioaddr = tp->ioaddr;
 	struct cmd_desc xp_cmd;
 	int err;
@@ -1832,20 +1831,29 @@ typhoon_sleep(struct typhoon *tp, pci_power_t state, __le16 events)
 	 */
 	netif_carrier_off(tp->dev);
 
+	return 0;
+}
+
+static int
+typhoon_sleep(struct typhoon *tp, pci_power_t state, __le16 events)
+{
+	int err;
+
+	err = typhoon_sleep_early(tp, events);
+
+	if (err)
+		return err;
+
 	pci_enable_wake(tp->pdev, state, 1);
-	pci_disable_device(pdev);
-	return pci_set_power_state(pdev, state);
+	pci_disable_device(tp->pdev);
+	return pci_set_power_state(tp->pdev, state);
 }
 
 static int
 typhoon_wakeup(struct typhoon *tp, int wait_type)
 {
-	struct pci_dev *pdev = tp->pdev;
 	void __iomem *ioaddr = tp->ioaddr;
 
-	pci_set_power_state(pdev, PCI_D0);
-	pci_restore_state(pdev);
-
 	/* Post 2.x.x versions of the Sleep Image require a reset before
 	 * we can download the Runtime Image. But let's not make users of
 	 * the old firmware pay for the reset.
@@ -2049,6 +2057,9 @@ typhoon_open(struct net_device *dev)
 	if (err)
 		goto out;
 
+	pci_set_power_state(tp->pdev, PCI_D0);
+	pci_restore_state(tp->pdev);
+
 	err = typhoon_wakeup(tp, WaitSleep);
 	if (err < 0) {
 		netdev_err(dev, "unable to wakeup device\n");
@@ -2114,11 +2125,10 @@ typhoon_close(struct net_device *dev)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int
-typhoon_resume(struct pci_dev *pdev)
+static int __maybe_unused
+typhoon_resume(struct device *dev_d)
 {
-	struct net_device *dev = pci_get_drvdata(pdev);
+	struct net_device *dev = dev_get_drvdata(dev_d);
 	struct typhoon *tp = netdev_priv(dev);
 
 	/* If we're down, resume when we are upped.
@@ -2144,9 +2154,10 @@ typhoon_resume(struct pci_dev *pdev)
 	return -EBUSY;
 }
 
-static int
-typhoon_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __maybe_unused
+typhoon_suspend(struct device *dev_d)
 {
+	struct pci_dev *pdev = to_pci_dev(dev_d);
 	struct net_device *dev = pci_get_drvdata(pdev);
 	struct typhoon *tp = netdev_priv(dev);
 	struct cmd_desc xp_cmd;
@@ -2190,18 +2201,19 @@ typhoon_suspend(struct pci_dev *pdev, pm_message_t state)
 		goto need_resume;
 	}
 
-	if (typhoon_sleep(tp, pci_choose_state(pdev, state), tp->wol_events) < 0) {
+	if (typhoon_sleep_early(tp, tp->wol_events) < 0) {
 		netdev_err(dev, "unable to put card to sleep\n");
 		goto need_resume;
 	}
 
+	device_wakeup_enable(dev_d);
+
 	return 0;
 
 need_resume:
-	typhoon_resume(pdev);
+	typhoon_resume(dev_d);
 	return -EBUSY;
 }
-#endif
 
 static int
 typhoon_test_mmio(struct pci_dev *pdev)
@@ -2533,15 +2545,14 @@ typhoon_remove_one(struct pci_dev *pdev)
 	free_netdev(dev);
 }
 
+static SIMPLE_DEV_PM_OPS(typhoon_pm_ops, typhoon_suspend, typhoon_resume);
+
 static struct pci_driver typhoon_driver = {
 	.name		= KBUILD_MODNAME,
 	.id_table	= typhoon_pci_tbl,
 	.probe		= typhoon_init_one,
 	.remove		= typhoon_remove_one,
-#ifdef CONFIG_PM
-	.suspend	= typhoon_suspend,
-	.resume		= typhoon_resume,
-#endif
+	.driver.pm	= &typhoon_pm_ops,
 };
 
 static int __init
-- 
2.27.0



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