[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>

3 files changed, 113 insertions, 7 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);
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 = {
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 4267246df516..1f2caa01ec92 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2169,6 +2169,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
         u32 status = 0;
         hba = container_of(work, struct ufs_hba, eeh_work);
 
+        pm_runtime_get_sync(hba->dev);
         err = ufshcd_get_ee_status(hba, &status);
         if (err) {
                 dev_err(hba->dev, "%s: failed to get exception status %d\n",
@@ -2184,6 +2185,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
                                         __func__, err);
         }
 out:
+        pm_runtime_put_sync(hba->dev);
         return;
 }
 
@@ -2196,9 +2198,11 @@ static void ufshcd_fatal_err_handler(struct work_struct *work)
         struct ufs_hba *hba;
         hba = container_of(work, struct ufs_hba, feh_workq);
 
+        pm_runtime_get_sync(hba->dev);
         /* check if reset is already in progress */
         if (hba->ufshcd_state != UFSHCD_STATE_RESET)
                 ufshcd_do_reset(hba);
+        pm_runtime_put_sync(hba->dev);
 }
 
 /**
@@ -2500,6 +2504,7 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 
         ufshcd_force_reset_auto_bkops(hba);
         scsi_scan_host(hba->host);
+        pm_runtime_put_sync(hba->dev);
 out:
         return;
 }
@@ -2721,6 +2726,9 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
 
         *hba_handle = hba;
 
+        /* Hold auto suspend until async scan completes */
+        pm_runtime_get_sync(dev);
+
         async_schedule(ufshcd_async_scan, hba);
 
         return 0;