diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index b64502d..e89daf1 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -266,7 +266,7 @@
 
 static int iommu_init_device(struct device *dev)
 {
-	struct pci_dev *dma_pdev, *pdev = to_pci_dev(dev);
+	struct pci_dev *dma_pdev = NULL, *pdev = to_pci_dev(dev);
 	struct iommu_dev_data *dev_data;
 	struct iommu_group *group;
 	u16 alias;
@@ -293,7 +293,9 @@
 		dev_data->alias_data = alias_data;
 
 		dma_pdev = pci_get_bus_and_slot(alias >> 8, alias & 0xff);
-	} else
+	}
+
+	if (dma_pdev == NULL)
 		dma_pdev = pci_dev_get(pdev);
 
 	/* Account for quirked devices */
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 7e83370..f3b99e1 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -256,72 +256,78 @@
 {
 }
 
-int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
+static inline int iommu_attach_group(struct iommu_domain *domain,
+				     struct iommu_group *group)
 {
 	return -ENODEV;
 }
 
-void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
+static inline void iommu_detach_group(struct iommu_domain *domain,
+				      struct iommu_group *group)
 {
 }
 
-struct iommu_group *iommu_group_alloc(void)
+static inline struct iommu_group *iommu_group_alloc(void)
 {
 	return ERR_PTR(-ENODEV);
 }
 
-void *iommu_group_get_iommudata(struct iommu_group *group)
+static inline void *iommu_group_get_iommudata(struct iommu_group *group)
 {
 	return NULL;
 }
 
-void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
-			       void (*release)(void *iommu_data))
+static inline void iommu_group_set_iommudata(struct iommu_group *group,
+					     void *iommu_data,
+					     void (*release)(void *iommu_data))
 {
 }
 
-int iommu_group_set_name(struct iommu_group *group, const char *name)
+static inline int iommu_group_set_name(struct iommu_group *group,
+				       const char *name)
 {
 	return -ENODEV;
 }
 
-int iommu_group_add_device(struct iommu_group *group, struct device *dev)
+static inline int iommu_group_add_device(struct iommu_group *group,
+					 struct device *dev)
 {
 	return -ENODEV;
 }
 
-void iommu_group_remove_device(struct device *dev)
+static inline void iommu_group_remove_device(struct device *dev)
 {
 }
 
-int iommu_group_for_each_dev(struct iommu_group *group, void *data,
-			     int (*fn)(struct device *, void *))
+static inline int iommu_group_for_each_dev(struct iommu_group *group,
+					   void *data,
+					   int (*fn)(struct device *, void *))
 {
 	return -ENODEV;
 }
 
-struct iommu_group *iommu_group_get(struct device *dev)
+static inline struct iommu_group *iommu_group_get(struct device *dev)
 {
 	return NULL;
 }
 
-void iommu_group_put(struct iommu_group *group)
+static inline void iommu_group_put(struct iommu_group *group)
 {
 }
 
-int iommu_group_register_notifier(struct iommu_group *group,
-				  struct notifier_block *nb)
+static inline int iommu_group_register_notifier(struct iommu_group *group,
+						struct notifier_block *nb)
 {
 	return -ENODEV;
 }
 
-int iommu_group_unregister_notifier(struct iommu_group *group,
-				    struct notifier_block *nb)
+static inline int iommu_group_unregister_notifier(struct iommu_group *group,
+						  struct notifier_block *nb)
 {
 	return 0;
 }
 
-int iommu_group_id(struct iommu_group *group)
+static inline int iommu_group_id(struct iommu_group *group)
 {
 	return -ENODEV;
 }