[PATCH 1/1] arm: mm: Fix comments in sg_sync functions

[Sakari Ailus]

The comment on the usage of arm_dma_sync_sg_for_cpu(),
arm_dma_sync_sg_for_device(), arm_iommu_sync_sg_for_cpu() and
arm_iommu_sync_sg_for_device() functions wrongly noted that the "nelems"
parameter is the number of sglist entries returned by dma_map_sg(), while
this must be the number of entiries passed to dma_map_sg() instead.

Suggested-by: Daniel Kurtz <djkurtz at chromium.org>
Signed-off-by: Sakari Ailus <sakari.ailus at linux.intel.com>
---
Hi folks,

This related patch was applied to Jonathan Corbet's tree:

<URL:http://www.spinics.net/lists/linux-doc/msg31801.html>

The comments were indeed wrong. This may have contributed to a related
videobuf2 bug:

<URL:http://www.spinics.net/lists/linux-media/msg93765.html>

 arch/arm/mm/dma-mapping.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index e626043..1c0154a 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -958,7 +958,7 @@ void arm_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
  * arm_dma_sync_sg_for_cpu
  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
  * @sg: list of buffers
- * @nents: number of buffers to map (returned from dma_map_sg)
+ * @nents: number of buffers to sync (same as was passed to dma_map_sg)
  * @dir: DMA transfer direction (same as was passed to dma_map_sg)
  */
 void arm_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
@@ -977,7 +977,7 @@ void arm_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
  * arm_dma_sync_sg_for_device
  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
  * @sg: list of buffers
- * @nents: number of buffers to map (returned from dma_map_sg)
+ * @nents: number of buffers to sync (same as was passed to dma_map_sg)
  * @dir: DMA transfer direction (same as was passed to dma_map_sg)
  */
 void arm_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
@@ -1672,7 +1672,7 @@ void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
  * arm_iommu_sync_sg_for_cpu
  * @dev: valid struct device pointer
  * @sg: list of buffers
- * @nents: number of buffers to map (returned from dma_map_sg)
+ * @nents: number of buffers to sync (same as was passed to dma_map_sg)
  * @dir: DMA transfer direction (same as was passed to dma_map_sg)
  */
 void arm_iommu_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
@@ -1690,7 +1690,7 @@ void arm_iommu_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
  * arm_iommu_sync_sg_for_device
  * @dev: valid struct device pointer
  * @sg: list of buffers
- * @nents: number of buffers to map (returned from dma_map_sg)
+ * @nents: number of buffers to sync (same as was passed to dma_map_sg)
  * @dir: DMA transfer direction (same as was passed to dma_map_sg)
  */
 void arm_iommu_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
-- 
2.1.0.231.g7484e3b