On Wed, Jun 17, 2015 at 01:33:24PM +0200, Boris Brezillon wrote:

Actually, I think I don't need to save the dma_map_sg return val, since
I'm using the sg_next function to iterate over the scatterlist. Am I
right ?
IOW, is the ->map_sg() function (in dma_map_ops) supposed to merge the
contiguous entries and then flag the unused entries with the is_chain
flag ?

Right.  If you're simply using sg_dma_length in conjunction with
sg_next then you don't need the new length.

Cheers,
-- 
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