iommu/mediatek: Add error handle for mtk_iommu_probe

In the original code, we lack the error handle. This patch adds them.
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Link: https://lore.kernel.org/r/20210111111914.22211-18-yong.wu@mediatek.comSigned-off-by: Will Deacon <will@kernel.org>

drivers/iommu/mtk_iommu.c

@@ -739,15 +739,30 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 
 	ret = iommu_device_register(&data->iommu);
 	if (ret)
-		return ret;
+		goto out_sysfs_remove;
 
 	spin_lock_init(&data->tlb_lock);
 	list_add_tail(&data->list, &m4ulist);
 
-	if (!iommu_present(&platform_bus_type))
-		bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
+	if (!iommu_present(&platform_bus_type)) {
+		ret = bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
+		if (ret)
+			goto out_list_del;
+	}
 
-	return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
+	ret = component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
+	if (ret)
+		goto out_bus_set_null;
+	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);
+out_sysfs_remove:
+	iommu_device_sysfs_remove(&data->iommu);
+	return ret;
 }
 
 static int mtk_iommu_remove(struct platform_device *pdev)