From: Peter Wang <peter.wang@mediatek.com>
Date: Wed, 3 Sep 2025 02:44:39 +0000 (+0800)
Subject: scsi: ufs: host: mediatek: Correct system PM flow
X-Git-Tag: v6.17.8~354
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1323030fcab06b12d66980be7b4d069f5fc38109;p=thirdparty%2Fkernel%2Fstable.git

scsi: ufs: host: mediatek: Correct system PM flow

[ Upstream commit 77b96ef70b6ba46e3473e5e3a66095c4bc0e93a4 ]

Refine the system power management (PM) flow by skipping low power mode
(LPM) and MTCMOS settings if runtime PM is already applied. Prevent
redundant operations to ensure a more efficient PM process.

Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/ufs/host/ufs-mediatek.c b/drivers/ufs/host/ufs-mediatek.c
index 6bdbbee1f0708..91081d2aabe44 100644
--- a/drivers/ufs/host/ufs-mediatek.c
+++ b/drivers/ufs/host/ufs-mediatek.c
@@ -2264,27 +2264,38 @@ static int ufs_mtk_system_suspend(struct device *dev)
 
 	ret = ufshcd_system_suspend(dev);
 	if (ret)
-		return ret;
+		goto out;
+
+	if (pm_runtime_suspended(hba->dev))
+		goto out;
 
 	ufs_mtk_dev_vreg_set_lpm(hba, true);
 
 	if (ufs_mtk_is_rtff_mtcmos(hba))
 		ufs_mtk_mtcmos_ctrl(false, res);
 
-	return 0;
+out:
+	return ret;
 }
 
 static int ufs_mtk_system_resume(struct device *dev)
 {
+	int ret = 0;
 	struct ufs_hba *hba = dev_get_drvdata(dev);
 	struct arm_smccc_res res;
 
+	if (pm_runtime_suspended(hba->dev))
+		goto out;
+
 	ufs_mtk_dev_vreg_set_lpm(hba, false);
 
 	if (ufs_mtk_is_rtff_mtcmos(hba))
 		ufs_mtk_mtcmos_ctrl(true, res);
 
-	return ufshcd_system_resume(dev);
+out:
+	ret = ufshcd_system_resume(dev);
+
+	return ret;
 }
 #endif