summaryrefslogtreecommitdiff
path: root/drivers/scsi/ufs
diff options
context:
space:
mode:
authorSayali Lokhande <sayalil@codeaurora.org>2020-02-10 19:40:44 -0800
committerMartin K. Petersen <martin.petersen@oracle.com>2020-02-12 19:42:34 -0500
commit2824ec9f9e8116670e383a9db8df301d10507ca9 (patch)
tree3e2a33d8209e6ef728f07c24e218aa2d990842c0 /drivers/scsi/ufs
parent518b32f1ddf5830698f270272d2ca465e788a273 (diff)
scsi: ufs: Flush exception event before suspend
Exception event can be raised by the device when system suspend is in progress. This will result in unclocked register access in exception event handler as clocks will be turned off during suspend. This change makes sure to flush exception event handler work in suspend before disabling clocks to avoid unclocked register access issue. Link: https://lore.kernel.org/r/1581392451-28743-2-git-send-email-cang@codeaurora.org Reviewed-by: Bean Huo <beanhuo@micron.com> Signed-off-by: Sayali Lokhande <sayalil@codeaurora.org> Signed-off-by: Asutosh Das <asutoshd@codeaurora.org> Signed-off-by: Can Guo <cang@codeaurora.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/ufs')
-rw-r--r--drivers/scsi/ufs/ufshcd.c21
1 files changed, 18 insertions, 3 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 214a3f373dd8..bae0a406ab7c 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4730,8 +4730,15 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
* UFS device needs urgent BKOPs.
*/
if (!hba->pm_op_in_progress &&
- ufshcd_is_exception_event(lrbp->ucd_rsp_ptr))
- schedule_work(&hba->eeh_work);
+ ufshcd_is_exception_event(lrbp->ucd_rsp_ptr) &&
+ schedule_work(&hba->eeh_work)) {
+ /*
+ * Prevent suspend once eeh_work is scheduled
+ * to avoid deadlock between ufshcd_suspend
+ * and exception event handler.
+ */
+ pm_runtime_get_noresume(hba->dev);
+ }
break;
case UPIU_TRANSACTION_REJECT_UPIU:
/* TODO: handle Reject UPIU Response */
@@ -5184,7 +5191,14 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
out:
ufshcd_scsi_unblock_requests(hba);
- pm_runtime_put_sync(hba->dev);
+ /*
+ * pm_runtime_get_noresume is called while scheduling
+ * eeh_work to avoid suspend racing with exception work.
+ * Hence decrement usage counter using pm_runtime_put_noidle
+ * to allow suspend on completion of exception event handler.
+ */
+ pm_runtime_put_noidle(hba->dev);
+ pm_runtime_put(hba->dev);
return;
}
@@ -7925,6 +7939,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
goto enable_gating;
}
+ flush_work(&hba->eeh_work);
ret = ufshcd_link_state_transition(hba, req_link_state, 1);
if (ret)
goto set_dev_active;