[PATCH] scsi: ufs: Fix a bug in ufshcd_system_resume()

[Yang Yang]

During system resume, ufshcd_system_resume() won't resume UFS host if
runtime suspended. After that, scsi_bus_resume() try to set SCSI host's
RPM status to RPM_ACTIVE, this will fail because UFS host's RPM status
is still RPM_SUSPENDED. So fix it.

    scsi host0: scsi_runtime_suspend()
		ufshcd_runtime_suspend()
    scsi host0: scsi_bus_suspend()
		ufshcd_system_suspend()
    ----------------------------------
		ufshcd_pltfrm_resume()
    scsi host0: scsi_bus_resume()
    scsi host0: scsi_bus_resume_common()
    scsi host0: pm_runtime_set_active(dev)

    scsi host0: runtime PM trying to activate child device host0 but parent
    (8800000.ufshc) is not active

Fixes: 57d104c153d3 ("ufs: add UFS power management support")
Signed-off-by: Yang Yang <yang.yang@xxxxxxxx>
---
 drivers/scsi/ufs/ufshcd.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b8f573a02713..9e666e1ad58c 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8767,11 +8767,7 @@ int ufshcd_system_resume(struct ufs_hba *hba)
 	if (!hba)
 		return -EINVAL;
 
-	if (!hba->is_powered || pm_runtime_suspended(hba->dev))
-		/*
-		 * Let the runtime resume take care of resuming
-		 * if runtime suspended.
-		 */
+	if (!hba->is_powered)
 		goto out;
 	else
 		ret = ufshcd_resume(hba, UFS_SYSTEM_PM);
@@ -8779,8 +8775,15 @@ int ufshcd_system_resume(struct ufs_hba *hba)
 	trace_ufshcd_system_resume(dev_name(hba->dev), ret,
 		ktime_to_us(ktime_sub(ktime_get(), start)),
 		hba->curr_dev_pwr_mode, hba->uic_link_state);
-	if (!ret)
+	if (!ret) {
 		hba->is_sys_suspended = false;
+
+		if (pm_runtime_suspended(hba->dev)) {
+			pm_runtime_disable(hba->dev);
+			pm_runtime_set_active(hba->dev);
+			pm_runtime_enable(hba->dev);
+		}
+	}
 	return ret;
 }
 EXPORT_SYMBOL(ufshcd_system_resume);
-- 
2.17.1