[PATCH]iommu: make return value consistence

[Wang YanQing <udknight@gmail.com>]

if we don't define CONFIG_IOMMU_API the
dummy functions alway return -ENODEV
or -EINVAL except three function, so convert
them to the same behavior to make consistence

Signed-off-by: Wang YanQing <udknight@gmail.com>
---
 include/linux/iommu.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index f4a49a6..16e84f6 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -210,7 +210,7 @@ static inline bool iommu_present(struct bus_type *bus)
 
 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
 {
-	return NULL;
+	return ERR_PTR(-ENODEV);
 }
 
 static inline void iommu_domain_free(struct iommu_domain *domain)
@@ -275,7 +275,7 @@ static inline struct iommu_group *iommu_group_alloc(void)
 
 static inline void *iommu_group_get_iommudata(struct iommu_group *group)
 {
-	return NULL;
+	return ERR_PTR(-EINVAL);
 }
 
 static inline void iommu_group_set_iommudata(struct iommu_group *group,
@@ -309,7 +309,7 @@ static inline int iommu_group_for_each_dev(struct iommu_group *group,
 
 static inline struct iommu_group *iommu_group_get(struct device *dev)
 {
-	return NULL;
+	return ERR_PTR(-ENODEV);
 }
 
 static inline void iommu_group_put(struct iommu_group *group)
-- 
1.7.11.1.116.g8228a23