diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c
index f1754efcfe74..e996c1418b24 100644
--- a/drivers/iommu/mtk_iommu_v1.c
+++ b/drivers/iommu/mtk_iommu_v1.c
@@ -420,6 +420,8 @@ static int mtk_iommu_v1_create_mapping(struct device *dev, struct of_phandle_arg
 			return -EINVAL;
 
 		dev_iommu_priv_set(dev, platform_get_drvdata(m4updev));
+
+		put_device(&m4updev->dev);
 	}
 
 	ret = iommu_fwspec_add_ids(dev, args->args, 1);