[Linux-kernel-mentees] [PATCH v1 2/5] cardreader/rtsx_pcr.c: use generic power management

[Vaibhav Gupta]

Drivers should not use legacy power management as they have to manage power
states and related operations, for the device, themselves. This driver was
handling them with the help of PCI helper functions like
pci_save/restore_state(), pci_enable/disable_device(), etc.

With generic PM, all essentials will be handled by the  PCI core. Driver
needs to do only device-specific operations.

The driver was also using pci_enable_wake(...,..., 0) to disable wake. Use
device_wakeup_disable() instead.

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40 at gmail.com>
---
 drivers/misc/cardreader/rtsx_pcr.c | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/drivers/misc/cardreader/rtsx_pcr.c b/drivers/misc/cardreader/rtsx_pcr.c
index 0d5928bc1b6d..ca5212cba1c0 100644
--- a/drivers/misc/cardreader/rtsx_pcr.c
+++ b/drivers/misc/cardreader/rtsx_pcr.c
@@ -1604,10 +1604,9 @@ static void rtsx_pci_remove(struct pci_dev *pcidev)
 		pci_name(pcidev), (int)pcidev->vendor, (int)pcidev->device);
 }
 
-#ifdef CONFIG_PM
-
-static int rtsx_pci_suspend(struct pci_dev *pcidev, pm_message_t state)
+static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
 {
+	struct pci_dev *pcidev = to_pci_dev(dev_d);
 	struct pcr_handle *handle;
 	struct rtsx_pcr *pcr;
 
@@ -1623,17 +1622,15 @@ static int rtsx_pci_suspend(struct pci_dev *pcidev, pm_message_t state)
 
 	rtsx_pci_power_off(pcr, HOST_ENTER_S3);
 
-	pci_save_state(pcidev);
-	pci_enable_wake(pcidev, pci_choose_state(pcidev, state), 0);
-	pci_disable_device(pcidev);
-	pci_set_power_state(pcidev, pci_choose_state(pcidev, state));
+	device_wakeup_disable(dev_d);
 
 	mutex_unlock(&pcr->pcr_mutex);
 	return 0;
 }
 
-static int rtsx_pci_resume(struct pci_dev *pcidev)
+static int __maybe_unused rtsx_pci_resume(struct device *dev_d)
 {
+	struct pci_dev *pcidev = to_pci_dev(dev_d);
 	struct pcr_handle *handle;
 	struct rtsx_pcr *pcr;
 	int ret = 0;
@@ -1645,11 +1642,6 @@ static int rtsx_pci_resume(struct pci_dev *pcidev)
 
 	mutex_lock(&pcr->pcr_mutex);
 
-	pci_set_power_state(pcidev, PCI_D0);
-	pci_restore_state(pcidev);
-	ret = pci_enable_device(pcidev);
-	if (ret)
-		goto out;
 	pci_set_master(pcidev);
 
 	ret = rtsx_pci_write_register(pcr, HOST_SLEEP_STATE, 0x03, 0x00);
@@ -1667,6 +1659,8 @@ static int rtsx_pci_resume(struct pci_dev *pcidev)
 	return ret;
 }
 
+#ifdef CONFIG_PM
+
 static void rtsx_pci_shutdown(struct pci_dev *pcidev)
 {
 	struct pcr_handle *handle;
@@ -1686,19 +1680,18 @@ static void rtsx_pci_shutdown(struct pci_dev *pcidev)
 
 #else /* CONFIG_PM */
 
-#define rtsx_pci_suspend NULL
-#define rtsx_pci_resume NULL
 #define rtsx_pci_shutdown NULL
 
 #endif /* CONFIG_PM */
 
+static SIMPLE_DEV_PM_OPS(rtsx_pci_pm_ops, rtsx_pci_suspend, rtsx_pci_resume);
+
 static struct pci_driver rtsx_pci_driver = {
 	.name = DRV_NAME_RTSX_PCI,
 	.id_table = rtsx_pci_ids,
 	.probe = rtsx_pci_probe,
 	.remove = rtsx_pci_remove,
-	.suspend = rtsx_pci_suspend,
-	.resume = rtsx_pci_resume,
+	.driver.pm = &rtsx_pci_pm_ops,
 	.shutdown = rtsx_pci_shutdown,
 };
 module_pci_driver(rtsx_pci_driver);
-- 
2.27.0