iommu/mtk: Clean up bus_set_iommu()

Stop calling bus_set_iommu() since it's now unnecessary, and simplify
the probe failure paths accordingly.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/9134322ecd24030eebeac73f37ca579094cc7df0.1660572783.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/mtk_iommu.c

@@ -1243,30 +1243,13 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 		data->hw_list = &data->hw_list_head;
 	}
 
-	if (!iommu_present(&platform_bus_type)) {
-		ret = bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
-		if (ret)
-			goto out_list_del;
-	}
-
 	if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM)) {
 		ret = component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
 		if (ret)
-			goto out_bus_set_null;
-	} else if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_INFRA) &&
-		   MTK_IOMMU_HAS_FLAG(data->plat_data, IFA_IOMMU_PCIE_SUPPORT)) {
-#ifdef CONFIG_PCI
-		if (!iommu_present(&pci_bus_type)) {
-			ret = bus_set_iommu(&pci_bus_type, &mtk_iommu_ops);
-			if (ret) /* PCIe fail don't affect platform_bus. */
-				goto out_list_del;
-		}
-#endif
+			goto out_list_del;
 	}
 	return ret;
 
-out_bus_set_null:
-	bus_set_iommu(&platform_bus_type, NULL);
 out_list_del:
 	list_del(&data->list);
 	iommu_device_unregister(&data->iommu);
@@ -1294,11 +1277,6 @@ static int mtk_iommu_remove(struct platform_device *pdev)
 	if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM)) {
 		device_link_remove(data->smicomm_dev, &pdev->dev);
 		component_master_del(&pdev->dev, &mtk_iommu_com_ops);
-	} else if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_INFRA) &&
-		   MTK_IOMMU_HAS_FLAG(data->plat_data, IFA_IOMMU_PCIE_SUPPORT)) {
-#ifdef CONFIG_PCI
-		bus_set_iommu(&pci_bus_type, NULL);
-#endif
 	}
 	pm_runtime_disable(&pdev->dev);
 	for (i = 0; i < data->plat_data->banks_num; i++) {

drivers/iommu/mtk_iommu_v1.c

@@ -691,19 +691,11 @@ static int mtk_iommu_v1_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_sysfs_remove;
 
-	if (!iommu_present(&platform_bus_type)) {
-		ret = bus_set_iommu(&platform_bus_type,  &mtk_iommu_v1_ops);
-		if (ret)
-			goto out_dev_unreg;
-	}
-
 	ret = component_master_add_with_match(dev, &mtk_iommu_v1_com_ops, match);
 	if (ret)
-		goto out_bus_set_null;
+		goto out_dev_unreg;
 	return ret;
 
-out_bus_set_null:
-	bus_set_iommu(&platform_bus_type, NULL);
 out_dev_unreg:
 	iommu_device_unregister(&data->iommu);
 out_sysfs_remove:
@@ -718,9 +710,6 @@ static int mtk_iommu_v1_remove(struct platform_device *pdev)
 	iommu_device_sysfs_remove(&data->iommu);
 	iommu_device_unregister(&data->iommu);
 
-	if (iommu_present(&platform_bus_type))
-		bus_set_iommu(&platform_bus_type, NULL);
-
 	clk_disable_unprepare(data->bclk);
 	devm_free_irq(&pdev->dev, data->irq, data);
 	component_master_del(&pdev->dev, &mtk_iommu_v1_com_ops);