From: Can Guo <cang@codeaurora.org>
Date: Sun, 25 Apr 2021 20:48:40 -0700
Subject: scsi: ufs: core: Narrow down fast path in system suspend path
Git-commit: ce4f62f9dd8cf43ac044045ed598a0b80ef33890
Patch-mainline: v5.13-rc1
References: bsc#1186551

If spm_lvl is set to 0 or 1, when system suspend kicks start and HBA is
runtime active, system suspend may just bail without doing anything (the
fast path), leaving other contexts still running, e.g., clock gating and
clock scaling. When system resume kicks start, concurrency can happen
between ufshcd_resume() and these contexts, leading to various stability
issues.

Add a check against HBA's runtime state and allowing fast path only if HBA
is runtime suspended, otherwise let system suspend go ahead call
ufshcd_suspend(). This will guarantee that these contexts are stopped by
either runtime suspend or system suspend.

Link: https://lore.kernel.org/r/1619408921-30426-4-git-send-email-cang@codeaurora.org
Fixes: 0b257734344a ("scsi: ufs: optimize system suspend handling")
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Lee Duncan <lduncan@suse.com>
---
 drivers/scsi/ufs/ufshcd.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7621,7 +7621,8 @@ int ufshcd_system_suspend(struct ufs_hba
 	if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
 	     hba->curr_dev_pwr_mode) &&
 	    (ufs_get_pm_lvl_to_link_pwr_state(hba->spm_lvl) ==
-	     hba->uic_link_state))
+	     hba->uic_link_state) &&
+	     pm_runtime_suspended(hba->dev))
 		goto out;
 
 	if (pm_runtime_suspended(hba->dev)) {