[SCSI] ufs: Add runtime PM support for UFS host controller driver

Add runtime PM helpers to suspend/resume UFS controller at runtime.
Enable runtime PM by default for pci and platform drivers as the
initialized hardware can suspend if it is not used after bootup.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 56 insertions, 6 deletions

diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c
index 48be39a6f6d7..57ea9dd40bf4 100644
--- a/drivers/scsi/ufs/ufshcd-pci.c
+++ b/drivers/scsi/ufs/ufshcd-pci.c
@@ -35,6 +35,7 @@
 
 #include "ufshcd.h"
 #include <linux/pci.h>
+#include <linux/pm_runtime.h>
 
 #ifdef CONFIG_PM
 /**
@@ -44,7 +45,7 @@
  *
  * Returns -ENOSYS
  */
-static int ufshcd_pci_suspend(struct pci_dev *pdev, pm_message_t state)
+static int ufshcd_pci_suspend(struct device *dev)
 {
 	/*
 	 * TODO:
@@ -61,7 +62,7 @@ static int ufshcd_pci_suspend(struct pci_dev *pdev, pm_message_t state)
  *
  * Returns -ENOSYS
  */
-static int ufshcd_pci_resume(struct pci_dev *pdev)
+static int ufshcd_pci_resume(struct device *dev)
 {
 	/*
 	 * TODO:
@@ -71,8 +72,45 @@ static int ufshcd_pci_resume(struct pci_dev *pdev)
 
 	return -ENOSYS;
 }
+#else
+#define ufshcd_pci_suspend	NULL
+#define ufshcd_pci_resume	NULL
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_PM_RUNTIME
+static int ufshcd_pci_runtime_suspend(struct device *dev)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	if (!hba)
+		return 0;
+
+	return ufshcd_runtime_suspend(hba);
+}
+static int ufshcd_pci_runtime_resume(struct device *dev)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	if (!hba)
+		return 0;
+
+	return ufshcd_runtime_resume(hba);
+}
+static int ufshcd_pci_runtime_idle(struct device *dev)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	if (!hba)
+		return 0;
+
+	return ufshcd_runtime_idle(hba);
+}
+#else /* !CONFIG_PM_RUNTIME */
+#define ufshcd_pci_runtime_suspend	NULL
+#define ufshcd_pci_runtime_resume	NULL
+#define ufshcd_pci_runtime_idle	NULL
+#endif /* CONFIG_PM_RUNTIME */
+
 /**
  * ufshcd_pci_shutdown - main function to put the controller in reset state
  * @pdev: pointer to PCI device handle
@@ -91,6 +129,9 @@ static void ufshcd_pci_remove(struct pci_dev *pdev)
 {
 	struct ufs_hba *hba = pci_get_drvdata(pdev);
 
+	pm_runtime_forbid(&pdev->dev);
+	pm_runtime_get_noresume(&pdev->dev);
+
 	disable_irq(pdev->irq);
 	ufshcd_remove(hba);
 	pci_release_regions(pdev);
@@ -168,6 +209,8 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	}
 
 	pci_set_drvdata(pdev, hba);
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_allow(&pdev->dev);
 
 	return 0;
 
@@ -182,6 +225,14 @@ out_error:
 	return err;
 }
 
+static const struct dev_pm_ops ufshcd_pci_pm_ops = {
+	.suspend	= ufshcd_pci_suspend,
+	.resume		= ufshcd_pci_resume,
+	.runtime_suspend = ufshcd_pci_runtime_suspend,
+	.runtime_resume  = ufshcd_pci_runtime_resume,
+	.runtime_idle    = ufshcd_pci_runtime_idle,
+};
+
 static DEFINE_PCI_DEVICE_TABLE(ufshcd_pci_tbl) = {
 	{ PCI_VENDOR_ID_SAMSUNG, 0xC00C, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
 	{ }	/* terminate list */
@@ -195,10 +246,9 @@ static struct pci_driver ufshcd_pci_driver = {
 	.probe = ufshcd_pci_probe,
 	.remove = ufshcd_pci_remove,
 	.shutdown = ufshcd_pci_shutdown,
-#ifdef CONFIG_PM
-	.suspend = ufshcd_pci_suspend,
-	.resume = ufshcd_pci_resume,
-#endif
+	.driver = {
+		.pm = &ufshcd_pci_pm_ops
+	},
 };
 
 module_pci_driver(ufshcd_pci_driver);