path: root/drivers/dma/dmaengine.c
diff options
authorJassi Brar <>2011-10-13 12:33:30 +0530
committerVinod Koul <>2011-11-18 12:16:24 +0530
commitb14dab792dee3245b628e046d80a7fad5573fea6 (patch)
treec77574d19be7c150b57bd9a9b0184580c733621b /drivers/dma/dmaengine.c
parente0d23ef29ed637dc6bd739f590985746d9ad9caa (diff)
DMAEngine: Define interleaved transfer request api
Define a new api that could be used for doing fancy data transfers like interleaved to contiguous copy and vice-versa. Traditional SG_list based transfers tend to be very inefficient in such cases as where the interleave and chunk are only a few bytes, which call for a very condensed api to convey pattern of the transfer. This api supports all 4 variants of scatter-gather and contiguous transfer. Of course, neither can this api help transfers that don't lend to DMA by nature, i.e, scattered tiny read/writes with no periodic pattern. Also since now we support SLAVE channels that might not provide device_prep_slave_sg callback but device_prep_interleaved_dma, remove the BUG_ON check. Signed-off-by: Jassi Brar <> Acked-by: Barry Song <> [renamed dmaxfer_template to dma_interleaved_template did fixup after the enum dma_transfer_merge] Signed-off-by: Vinod Koul <>
Diffstat (limited to 'drivers/dma/dmaengine.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index b48967b499da..a6c6051ec858 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -693,12 +693,12 @@ int dma_async_device_register(struct dma_device *device)
BUG_ON(dma_has_cap(DMA_SG, device->cap_mask) &&
- BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
- !device->device_prep_slave_sg);
BUG_ON(dma_has_cap(DMA_CYCLIC, device->cap_mask) &&
BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ BUG_ON(dma_has_cap(DMA_INTERLEAVE, device->cap_mask) &&
+ !device->device_prep_interleaved_dma);