@@ -837,8 +837,6 @@ static int qcom_iommu_device_probe(struct platform_device *pdev)
 		goto err_pm_disable;
 	}
 
-	bus_set_iommu(&platform_bus_type, &qcom_iommu_ops);
-
 	if (qcom_iommu->local_base) {
 		pm_runtime_get_sync(dev);
 		writel_relaxed(0xffffffff, qcom_iommu->local_base + SMMU_INTR_SEL_NS);

@@ -856,8 +854,6 @@ static int qcom_iommu_device_remove(struct platform_device *pdev)
 {
 	struct qcom_iommu_dev *qcom_iommu = platform_get_drvdata(pdev);
 
-	bus_set_iommu(&platform_bus_type, NULL);
-
 	pm_runtime_force_suspend(&pdev->dev);
 	platform_set_drvdata(pdev, NULL);
 	iommu_device_sysfs_remove(&qcom_iommu->iommu);

@@ -476,11 +476,7 @@ int __init pamu_domain_init(void)
 	if (ret) {
 		iommu_device_sysfs_remove(&pamu_iommu);
 		pr_err("Can't register iommu device\n");
-		return ret;
 	}
 
-	bus_set_iommu(&platform_bus_type, &fsl_pamu_ops);
-	bus_set_iommu(&pci_bus_type, &fsl_pamu_ops);
-
 	return ret;
 }

@@ -3890,7 +3890,6 @@ static int __init probe_acpi_namespace_devices(void)
 					continue;
 				}
 
-				pn->dev->bus->iommu_ops = &intel_iommu_ops;
 				ret = iommu_probe_device(pn->dev);
 				if (ret)
 					break;

@@ -4023,7 +4022,6 @@ int __init intel_iommu_init(void)
 	}
 	up_read(&dmar_global_lock);
 
-	bus_set_iommu(&pci_bus_type, &intel_iommu_ops);
 	if (si_domain && !hw_pass_through)
 		register_memory_notifier(&intel_iommu_memory_nb);
 

@@ -1827,30 +1827,6 @@ int bus_iommu_probe(struct bus_type *bus)
 	return ret;
 }
 
-/**
- * bus_set_iommu - set iommu-callbacks for the bus
- * @bus: bus.
- * @ops: the callbacks provided by the iommu-driver
- *
- * This function is called by an iommu driver to set the iommu methods
- * used for a particular bus. Drivers for devices on that bus can use
- * the iommu-api after these ops are registered.
- * This special function is needed because IOMMUs are usually devices on
- * the bus itself, so the iommu drivers are not initialized when the bus
- * is set up. With this function the iommu-driver can set the iommu-ops
- * afterwards.
- */
-int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
-{
-	if (bus->iommu_ops && ops && bus->iommu_ops != ops)
-		return -EBUSY;
-
-	bus->iommu_ops = ops;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(bus_set_iommu);
-
 bool iommu_present(struct bus_type *bus)
 {
 	return bus->iommu_ops != NULL;

@@ -792,8 +792,6 @@ static int msm_iommu_probe(struct platform_device *pdev)
 		goto fail;
 	}
 
-	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
-
 	pr_info("device mapped at %p, irq %d with %d ctx banks\n",
 		iommu->base, iommu->irq, iommu->ncb);
 

@@ -1300,8 +1300,6 @@ static int rk_iommu_probe(struct platform_device *pdev)
 	if (!dma_dev)
 		dma_dev = &pdev->dev;
 
-	bus_set_iommu(&platform_bus_type, &rk_iommu_ops);
-
 	pm_runtime_enable(dev);
 
 	for (i = 0; i < iommu->num_irq; i++) {

@@ -390,9 +390,3 @@ static const struct iommu_ops s390_iommu_ops = {
 		.free		= s390_domain_free,
 	}
 };
-
-static int __init s390_iommu_init(void)
-{
-	return bus_set_iommu(&pci_bus_type, &s390_iommu_ops);
-}
-subsys_initcall(s390_iommu_init);

@@ -496,9 +496,6 @@ static int sprd_iommu_probe(struct platform_device *pdev)
 	if (ret)
 		goto remove_sysfs;
 
-	if (!iommu_present(&platform_bus_type))
-		bus_set_iommu(&platform_bus_type, &sprd_iommu_ops);
-
 	ret = sprd_iommu_clk_enable(sdev);
 	if (ret)
 		goto unregister_iommu;

@@ -534,8 +531,6 @@ static int sprd_iommu_remove(struct platform_device *pdev)
 	iommu_group_put(sdev->group);
 	sdev->group = NULL;
 
-	bus_set_iommu(&platform_bus_type, NULL);
-
 	platform_set_drvdata(pdev, NULL);
 	iommu_device_sysfs_remove(&sdev->iommu);
 	iommu_device_unregister(&sdev->iommu);

@@ -965,8 +965,6 @@ static int sun50i_iommu_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_unregister;
 
-	bus_set_iommu(&platform_bus_type, &sun50i_iommu_ops);
-
 	return 0;
 
 err_unregister:

@@ -416,7 +416,6 @@ static inline const struct iommu_ops *dev_iommu_ops(struct device *dev)
 	return dev->iommu->iommu_dev->ops;
 }
 
-extern int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops);
 extern int bus_iommu_probe(struct bus_type *bus);
 extern bool iommu_present(struct bus_type *bus);
 extern bool device_iommu_capable(struct device *dev, enum iommu_cap cap);