diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
index 9e512d1ea763..c16084a89ccf 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
@@ -121,6 +121,12 @@ conditions.
 		  supported as we are directly comparing client SID with ID bits
 		  of SMR registers.
 
+- qcom,deferred-regulator-disable-delay : The time delay for deferred regulator
+                  disable in ms. In case of unmap call, regulator is
+                  enabled/disabled. This may introduce additional delay. For
+                  clients who do not detach, it's not possible to keep regulator
+                  vote while smmu is attached. Type is <u32>.
+
 - clocks        : List of clocks to be used during SMMU register access. See
                   Documentation/devicetree/bindings/clock/clock-bindings.txt
                   for information about the format. For each clock specified
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 065379c1397f..f14812fdee6c 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -404,6 +404,7 @@ struct arm_smmu_device {
 	struct msm_bus_scale_pdata	*bus_pdata;
 
 	enum tz_smmu_device_id		sec_id;
+	int				regulator_defer;
 };
 
 struct arm_smmu_cfg {
@@ -950,7 +951,8 @@ static int arm_smmu_disable_regulators(struct arm_smmu_device *smmu)
 	arm_smmu_unprepare_clocks(smmu);
 	arm_smmu_unrequest_bus(smmu);
 	if (smmu->gdsc) {
-		ret = regulator_disable(smmu->gdsc);
+		ret = regulator_disable_deferred(smmu->gdsc,
+						 smmu->regulator_defer);
 		WARN(ret, "%s: Regulator disable failed\n",
 			dev_name(smmu->dev));
 	}
@@ -3610,6 +3612,12 @@ static int arm_smmu_init_regulators(struct arm_smmu_device *smmu)
 	if (!of_get_property(dev->of_node, "vdd-supply", NULL))
 		return 0;
 
+	if (!of_property_read_u32(dev->of_node,
+				  "qcom,deferred-regulator-disable-delay",
+				  &(smmu->regulator_defer)))
+		dev_info(dev, "regulator defer delay %d\n",
+			smmu->regulator_defer);
+
 	smmu->gdsc = devm_regulator_get(dev, "vdd");
 	if (IS_ERR(smmu->gdsc))
 		return PTR_ERR(smmu->gdsc);