On 23-04-21, 11:17, Lars-Peter Clausen wrote: > > It seems to me what we are missing from the DMAengine API is the equivalent > of device_prep_dma_memcpy() that is able to take SG lists. There is already > a memset_sg, it should be possible to add something similar for memcpy. You mean something like dmaengine_prep_dma_sg() which was removed? static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg( struct dma_chan *chan, struct scatterlist *dst_sg, unsigned int dst_nents, struct scatterlist *src_sg, unsigned int src_nents, unsigned long flags) The problem with this API is that it would work only when src_sg and dst_sg is of similar nature, if not then how should one go about copying...should we fill without a care for dst_sg being different than src_sg as long as total data to be copied has enough space in dst... We can always add this back if we have in-kernel user but the semantics of the API needs to be thought thru Thanks -- ~Vinod