[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, 49 insertions, 1 deletions

diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index c42db40d4e51..c5c28357fb63 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -34,6 +34,7 @@
  */
 
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 
 #include "ufshcd.h"
 
@@ -87,6 +88,40 @@ static int ufshcd_pltfrm_resume(struct device *dev)
 #define ufshcd_pltfrm_resume	NULL
 #endif
 
+#ifdef CONFIG_PM_RUNTIME
+static int ufshcd_pltfrm_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_pltfrm_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_pltfrm_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_pltfrm_runtime_suspend	NULL
+#define ufshcd_pltfrm_runtime_resume	NULL
+#define ufshcd_pltfrm_runtime_idle	NULL
+#endif /* CONFIG_PM_RUNTIME */
+
 /**
  * ufshcd_pltfrm_probe - probe routine of the driver
  * @pdev: pointer to Platform device handle
@@ -122,14 +157,22 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
 		goto out;
 	}
 
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
 	err = ufshcd_init(dev, &hba, mmio_base, irq);
 	if (err) {
 		dev_err(dev, "Intialization failed\n");
-		goto out;
+		goto out_disable_rpm;
 	}
 
 	platform_set_drvdata(pdev, hba);
 
+	return 0;
+
+out_disable_rpm:
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
 out:
 	return err;
 }
@@ -144,6 +187,8 @@ static int ufshcd_pltfrm_remove(struct platform_device *pdev)
 {
 	struct ufs_hba *hba =  platform_get_drvdata(pdev);
 
+	pm_runtime_get_sync(&(pdev)->dev);
+
 	disable_irq(hba->irq);
 	ufshcd_remove(hba);
 	return 0;
@@ -157,6 +202,9 @@ static const struct of_device_id ufs_of_match[] = {
 static const struct dev_pm_ops ufshcd_dev_pm_ops = {
 	.suspend	= ufshcd_pltfrm_suspend,
 	.resume		= ufshcd_pltfrm_resume,
+	.runtime_suspend = ufshcd_pltfrm_runtime_suspend,
+	.runtime_resume  = ufshcd_pltfrm_runtime_resume,
+	.runtime_idle    = ufshcd_pltfrm_runtime_idle,
 };
 
 static struct platform_driver ufshcd_pltfrm_driver = {