[PATCH v1 07/10] ufs: host: mediatek: Fix shutdown/suspend race condition

[peter.wang at mediatek.com]

From: Peter Wang <peter.wang at mediatek.com>

Address a race condition between shutdown and suspend
operations in the UFS Mediatek driver. Before entering
suspend, check if a shutdown is in progress to prevent
conflicts and ensure system stability.

Signed-off-by: Peter Wang <peter.wang at mediatek.com>
---
 drivers/ufs/core/ufshcd-priv.h  | 5 -----
 drivers/ufs/host/ufs-mediatek.c | 6 ++++++
 include/ufs/ufshcd.h            | 5 +++++
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index d0a2c963a27d..3ab50ece5abf 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -6,11 +6,6 @@
 #include <linux/pm_runtime.h>
 #include <ufs/ufshcd.h>
 
-static inline bool ufshcd_is_user_access_allowed(struct ufs_hba *hba)
-{
-	return !hba->shutting_down;
-}
-
 void ufshcd_schedule_eh_work(struct ufs_hba *hba);
 
 static inline bool ufshcd_keep_autobkops_enabled_except_suspend(
diff --git a/drivers/ufs/host/ufs-mediatek.c b/drivers/ufs/host/ufs-mediatek.c
index 18ce985970f3..c56c85b55ba4 100644
--- a/drivers/ufs/host/ufs-mediatek.c
+++ b/drivers/ufs/host/ufs-mediatek.c
@@ -2433,6 +2433,12 @@ static int ufs_mtk_system_suspend(struct device *dev)
 	struct arm_smccc_res res;
 	int ret;
 
+	/* Check if shutting down */
+	if (!ufshcd_is_user_access_allowed(hba)) {
+		ret = -EBUSY;
+		goto out;
+	}
+
 	ret = ufshcd_system_suspend(dev);
 	if (ret)
 		goto out;
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 109cbb36c02d..7df475ebd06d 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1436,6 +1436,11 @@ static inline int ufshcd_disable_host_tx_lcc(struct ufs_hba *hba)
 	return ufshcd_dme_set(hba, UIC_ARG_MIB(PA_LOCAL_TX_LCC_ENABLE), 0);
 }
 
+static inline bool ufshcd_is_user_access_allowed(struct ufs_hba *hba)
+{
+	return !hba->shutting_down;
+}
+
 void ufshcd_auto_hibern8_update(struct ufs_hba *hba, u32 ahit);
 void ufshcd_fixup_dev_quirks(struct ufs_hba *hba,
 			     const struct ufs_dev_quirk *fixups);
-- 
2.45.2