From 6ba99411b858bd70bae966633561e698cd6de38c Mon Sep 17 00:00:00 2001 From: Yoshihiro Shimoda Date: Wed, 28 Aug 2019 21:35:40 +0900 Subject: dma-mapping: introduce dma_get_merge_boundary() This patch adds a new DMA API "dma_get_merge_boundary". This function returns the DMA merge boundary if the DMA layer can merge the segments. This patch also adds the implementation for a new dma_map_ops pointer. Signed-off-by: Yoshihiro Shimoda Reviewed-by: Simon Horman Signed-off-by: Christoph Hellwig --- Documentation/DMA-API.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation/DMA-API.txt') diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index e47c63bd4887..9c4dd3d779ed 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -204,6 +204,14 @@ Returns the maximum size of a mapping for the device. The size parameter of the mapping functions like dma_map_single(), dma_map_page() and others should not be larger than the returned value. +:: + + unsigned long + dma_get_merge_boundary(struct device *dev); + +Returns the DMA merge boundary. If the device cannot merge any the DMA address +segments, the function returns 0. + Part Id - Streaming DMA mappings -------------------------------- -- cgit v1.2.3