@@ -690,6 +690,8 @@ int dma_async_device_register(struct dma_device *device)
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_INTERRUPT, device->cap_mask) &&
!device->device_prep_dma_interrupt);
+ BUG_ON(dma_has_cap(DMA_SG, device->cap_mask) &&
+ !device->device_prep_dma_sg);
BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
!device->device_prep_slave_sg);
BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
@@ -64,6 +64,7 @@ enum dma_transaction_type {
DMA_PQ_VAL,
DMA_MEMSET,
DMA_INTERRUPT,
+ DMA_SG,
DMA_PRIVATE,
DMA_ASYNC_TX,
DMA_SLAVE,
@@ -473,6 +474,11 @@ struct dma_device {
unsigned long flags);
struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
struct dma_chan *chan, unsigned long flags);
+ struct dma_async_tx_descriptor *(*device_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);
struct dma_async_tx_descriptor *(*device_prep_slave_sg)(
struct dma_chan *chan, struct scatterlist *sgl,
This adds support for scatterlist to scatterlist DMA transfers. A similar interface is exposed by the fsldma driver (through the DMA_SLAVE API) and by the ste_dma40 driver (through an exported function). This patch paves the way for making this type of copy operation a part of the generic DMAEngine API. Futher patches will add support in individual drivers. Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> --- drivers/dma/dmaengine.c | 2 ++ include/linux/dmaengine.h | 6 ++++++ 2 files changed, 8 insertions(+), 0 deletions(-)