[PATCH 1/2] scsi: ufs: core: Skip redundant variant resume after error recovery power-up

[Stanley Jhu]

Since commit eef1d74bf88f ("PM: runtime: Only set runtime_error on
suspend callback failures"), a failed W-LUN runtime resume leaves
ufs_device_wlun in RPM_SUSPENDED with power.runtime_error == 0. If
error recovery then powers up the host, ufshcd_vops_resume() is called
twice in a row without an intervening ufshcd_vops_suspend():

1. __ufshcd_wl_suspend() runs ufshcd_vops_suspend() at POST_CHANGE, and
   a failed W-LUN runtime resume rolls back through vendor_suspend: to
   keep the variant suspended while ufs_device_wlun stays RPM_SUSPENDED.
2. ufshcd_err_handling_prepare() sees ufs_device_wlun suspended and
   calls ufshcd_vops_resume(), while ufshcd_recover_pm_error() leaves
   ufs_device_wlun in RPM_SUSPENDED.
3. The next ufs_device_wlun runtime resume calls ufshcd_vops_resume()
   again with no ufshcd_vops_suspend() in between, leaking core_clk and
   iface_clk enable counts in ufs_qcom_resume() via qcom_ice_resume().

Track POST_CHANGE variant suspend state in hba->is_vops_suspended and
skip ufshcd_vops_resume() when already resumed so variant suspend and
resume callbacks remain paired 1:1 across error recovery.

Fixes: eef1d74bf88f ("PM: runtime: Only set runtime_error on suspend callback failures")
Cc: stable@xxxxxxxxxxxxxxx # v7.3+
Signed-off-by: Stanley Jhu <stanleyjhu@xxxxxxxxxx>
---
 drivers/ufs/core/ufshcd-priv.h | 21 ++++++++++++++++-----
 include/ufs/ufshcd.h           |  2 ++
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index e55c2a02c1f5..9e4d8174a0f0 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -236,20 +236,31 @@ static inline void ufshcd_vops_fixup_dev_quirks(struct ufs_hba *hba)
 }
 
 static inline int ufshcd_vops_suspend(struct ufs_hba *hba, enum ufs_pm_op op,
-				enum ufs_notify_change_status status)
+				      enum ufs_notify_change_status status)
 {
+	int ret = 0;
+
 	if (hba->vops && hba->vops->suspend)
-		return hba->vops->suspend(hba, op, status);
+		ret = hba->vops->suspend(hba, op, status);
+	if (!ret && status == POST_CHANGE)
+		hba->is_vops_suspended = true;
 
-	return 0;
+	return ret;
 }
 
 static inline int ufshcd_vops_resume(struct ufs_hba *hba, enum ufs_pm_op op)
 {
+	int ret = 0;
+
+	if (!hba->is_vops_suspended)
+		return 0;
+
 	if (hba->vops && hba->vops->resume)
-		return hba->vops->resume(hba, op);
+		ret = hba->vops->resume(hba, op);
+	if (!ret)
+		hba->is_vops_suspended = false;
 
-	return 0;
+	return ret;
 }
 
 static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index be62165b785e..cdcaccf9201b 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1038,6 +1038,7 @@ enum ufshcd_mcq_opr {
  * @devfreq: frequency scaling information owned by the devfreq core
  * @clk_scaling: frequency scaling information owned by the UFS driver
  * @is_sys_suspended: UFS device has been suspended because of system suspend
+ * @is_vops_suspended: tracks whether variant POST_CHANGE suspend is active
  * @urgent_bkops_lvl: keeps track of urgent bkops level for device
  * @is_urgent_bkops_lvl_checked: keeps track if the urgent bkops level for
  *  device is known or not.
@@ -1226,6 +1227,7 @@ struct ufs_hba {
 	struct devfreq *devfreq;
 	struct ufs_clk_scaling clk_scaling;
 	bool is_sys_suspended;
+	bool is_vops_suspended;
 
 	enum bkops_status urgent_bkops_lvl;
 	bool is_urgent_bkops_lvl_checked;
-- 
2.56.0.385.gac671c819a-goog