[PATCH v2 3/3] scsi: ufs: Let resume callback return -EBUSY after ufshcd_shutdown

[Bean Huo]

From: Bean Huo <bean...@micron.com>

After ufshcd_shutdown(), both UFS device and UFS LINk are powered off,
return '0' will mislead the upper PM layer since the device has not been
successfully resumed yet. This will let pm_runtime_get_sync() caller
mistakenly believe the device/LINK has been resumed, which leads to
request processing timeout that was en-queued later.

To fix this, let ufshcd_system/runtimie_resume() return -EBUSY in case of
hba->is_powered == false.

Signed-off-by: Bean Huo <bean...@micron.com>
---
 drivers/scsi/ufs/ufshcd.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add25a7e..e1bcac51c01f 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8950,14 +8950,16 @@ int ufshcd_system_resume(struct ufs_hba *hba)
                return -EINVAL;
        }
 
-       if (!hba->is_powered || pm_runtime_suspended(hba->dev))
+       if (!hba->is_powered || pm_runtime_suspended(hba->dev)) {
                /*
                 * Let the runtime resume take care of resuming
                 * if runtime suspended.
                 */
+               ret = -EBUSY;
                goto out;
-       else
+       } else {
                ret = ufshcd_resume(hba, UFS_SYSTEM_PM);
+       }
 out:
        trace_ufshcd_system_resume(dev_name(hba->dev), ret,
                ktime_to_us(ktime_sub(ktime_get(), start)),
@@ -9026,10 +9028,12 @@ int ufshcd_runtime_resume(struct ufs_hba *hba)
        if (!hba)
                return -EINVAL;
 
-       if (!hba->is_powered)
+       if (!hba->is_powered) {
+               ret = -EBUSY;
                goto out;
-       else
+       } else {
                ret = ufshcd_resume(hba, UFS_RUNTIME_PM);
+       }
 out:
        trace_ufshcd_runtime_resume(dev_name(hba->dev), ret,
                ktime_to_us(ktime_sub(ktime_get(), start)),
-- 
2.17.1