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 6bdbbee1f070887e8d5083619f3ed1d7f2446d73..91081d2aabe442645abc97de6bee5f38d527765f 100644 (file)
--- 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