diff options
| author |   Adrian Larumbe <adrianml@alumnos.upm.es> | 2021-11-01 18:08:24 +0000 |
|---|---|---|
| committer |   Vinod Koul <vkoul@kernel.org> | 2021-11-22 11:38:05 +0530 |
| commit | 3218910fd5858842a1dd98ce92b602f0878f8210 (patch) | |
| tree | 2490bc6c3812b72a3038b2a04ee9b55a73ef6958 | |
| parent | dmaengine: Add documentation for new memcpy scatter-gather function (diff) | |
| download | linux-dev-3218910fd5858842a1dd98ce92b602f0878f8210.tar.xz linux-dev-3218910fd5858842a1dd98ce92b602f0878f8210.zip | |
dmaengine: Add core function and capability check for DMA_MEMCPY_SG
This is the old DMA_SG interface that was removed in commit
c678fa66341c ("dmaengine: remove DMA_SG as it is dead code in kernel"). It
has been renamed to DMA_MEMCPY_SG to better match the MEMSET and MEMSET_SG
naming convention.
It should only be used for mem2mem copies, either main system memory or
CPU-addressable device memory (like video memory on a PCI graphics card).
Bringing back this interface was prompted by the need to use the Xilinx
CDMA device for mem2mem SG transfers.
Signed-off-by: Adrian Larumbe <adrianml@alumnos.upm.es>
Link: https://lore.kernel.org/r/20211101180825.241048-3-adrianml@alumnos.upm.es
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/dma/dmaengine.c | 7 | ||||
| -rw-r--r-- | include/linux/dmaengine.h | 20 |
2 files changed, 27 insertions, 0 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index d9f7c097cfd6..2cfa8458b51b 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -1159,6 +1159,13 @@ int dma_async_device_register(struct dma_device *device) return -EIO; } + if (dma_has_cap(DMA_MEMCPY_SG, device->cap_mask) && !device->device_prep_dma_memcpy_sg) { + dev_err(device->dev, + "Device claims capability %s, but op is not defined\n", + "DMA_MEMCPY_SG"); + return -EIO; + } + if (dma_has_cap(DMA_XOR, device->cap_mask) && !device->device_prep_dma_xor) { dev_err(device->dev, "Device claims capability %s, but op is not defined\n", diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 9000f3ffce8b..554a86665de9 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -50,6 +50,7 @@ enum dma_status { */ enum dma_transaction_type { DMA_MEMCPY, + DMA_MEMCPY_SG, DMA_XOR, DMA_PQ, DMA_XOR_VAL, @@ -891,6 +892,11 @@ struct dma_device { struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)( struct dma_chan *chan, dma_addr_t dst, dma_addr_t src, size_t len, unsigned long flags); + struct dma_async_tx_descriptor *(*device_prep_dma_memcpy_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_dma_xor)( struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src, unsigned int src_cnt, size_t len, unsigned long flags); @@ -1051,6 +1057,20 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memcpy( len, flags); } +static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memcpy_sg( + struct dma_chan *chan, + struct scatterlist *dst_sg, unsigned int dst_nents, + struct scatterlist *src_sg, unsigned int src_nents, + unsigned long flags) +{ + if (!chan || !chan->device || !chan->device->device_prep_dma_memcpy_sg) + return NULL; + + return chan->device->device_prep_dma_memcpy_sg(chan, dst_sg, dst_nents, + src_sg, src_nents, + flags); +} + static inline bool dmaengine_is_metadata_mode_supported(struct dma_chan *chan, enum dma_desc_metadata_mode mode) { |