diff options
Diffstat (limited to 'include/linux/dmaengine.h')
| -rw-r--r-- | include/linux/dmaengine.h | 99 |
1 files changed, 92 insertions, 7 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 75f53f874b2..679b349d9b6 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -23,7 +23,6 @@ #include <linux/device.h> #include <linux/uio.h> -#include <linux/dma-direction.h> #include <linux/scatterlist.h> #include <linux/bitmap.h> #include <asm/page.h> @@ -72,11 +71,93 @@ enum dma_transaction_type { DMA_ASYNC_TX, DMA_SLAVE, DMA_CYCLIC, + DMA_INTERLEAVE, +/* last transaction type for creation of the capabilities mask */ + DMA_TX_TYPE_END, }; -/* last transaction type for creation of the capabilities mask */ -#define DMA_TX_TYPE_END (DMA_CYCLIC + 1) +/** + * enum dma_transfer_direction - dma transfer mode and direction indicator + * @DMA_MEM_TO_MEM: Async/Memcpy mode + * @DMA_MEM_TO_DEV: Slave mode & From Memory to Device + * @DMA_DEV_TO_MEM: Slave mode & From Device to Memory + * @DMA_DEV_TO_DEV: Slave mode & From Device to Device + */ +enum dma_transfer_direction { + DMA_MEM_TO_MEM, + DMA_MEM_TO_DEV, + DMA_DEV_TO_MEM, + DMA_DEV_TO_DEV, + DMA_TRANS_NONE, +}; + +/** + * Interleaved Transfer Request + * ---------------------------- + * A chunk is collection of contiguous bytes to be transfered. + * The gap(in bytes) between two chunks is called inter-chunk-gap(ICG). + * ICGs may or maynot change between chunks. + * A FRAME is the smallest series of contiguous {chunk,icg} pairs, + * that when repeated an integral number of times, specifies the transfer. + * A transfer template is specification of a Frame, the number of times + * it is to be repeated and other per-transfer attributes. + * + * Practically, a client driver would have ready a template for each + * type of transfer it is going to need during its lifetime and + * set only 'src_start' and 'dst_start' before submitting the requests. + * + * + * | Frame-1 | Frame-2 | ~ | Frame-'numf' | + * |====....==.===...=...|====....==.===...=...| ~ |====....==.===...=...| + * + * == Chunk size + * ... ICG + */ + +/** + * struct data_chunk - Element of scatter-gather list that makes a frame. + * @size: Number of bytes to read from source. + * size_dst := fn(op, size_src), so doesn't mean much for destination. + * @icg: Number of bytes to jump after last src/dst address of this + * chunk and before first src/dst address for next chunk. + * Ignored for dst(assumed 0), if dst_inc is true and dst_sgl is false. + * Ignored for src(assumed 0), if src_inc is true and src_sgl is false. + */ +struct data_chunk { + size_t size; + size_t icg; +}; +/** + * struct dma_interleaved_template - Template to convey DMAC the transfer pattern + * and attributes. + * @src_start: Bus address of source for the first chunk. + * @dst_start: Bus address of destination for the first chunk. + * @dir: Specifies the type of Source and Destination. + * @src_inc: If the source address increments after reading from it. + * @dst_inc: If the destination address increments after writing to it. + * @src_sgl: If the 'icg' of sgl[] applies to Source (scattered read). + * Otherwise, source is read contiguously (icg ignored). + * Ignored if src_inc is false. + * @dst_sgl: If the 'icg' of sgl[] applies to Destination (scattered write). + * Otherwise, destination is filled contiguously (icg ignored). + * Ignored if dst_inc is false. + * @numf: Number of frames in this template. + * @frame_size: Number of chunks in a frame i.e, size of sgl[]. + * @sgl: Array of {chunk,icg} pairs that make up a frame. + */ +struct dma_interleaved_template { + dma_addr_t src_start; + dma_addr_t dst_start; + enum dma_transfer_direction dir; + bool src_inc; + bool dst_inc; + bool src_sgl; + bool dst_sgl; + size_t numf; + size_t frame_size; + struct data_chunk sgl[0]; +}; /** * enum dma_ctrl_flags - DMA flags to augment operation preparation, @@ -269,7 +350,7 @@ enum dma_slave_buswidth { * struct, if applicable. */ struct dma_slave_config { - enum dma_data_direction direction; + enum dma_transfer_direction direction; dma_addr_t src_addr; dma_addr_t dst_addr; enum dma_slave_buswidth src_addr_width; @@ -433,6 +514,7 @@ struct dma_tx_state { * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio. * The function takes a buffer of size buf_len. The callback function will * be called after period_len bytes have been transferred. + * @device_prep_interleaved_dma: Transfer expression in a generic way. * @device_control: manipulate all pending operations on a channel, returns * zero or error code * @device_tx_status: poll for transaction completion, the optional @@ -492,11 +574,14 @@ struct dma_device { struct dma_async_tx_descriptor *(*device_prep_slave_sg)( struct dma_chan *chan, struct scatterlist *sgl, - unsigned int sg_len, enum dma_data_direction direction, + unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_cyclic)( struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, - size_t period_len, enum dma_data_direction direction); + size_t period_len, enum dma_transfer_direction direction); + struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)( + struct dma_chan *chan, struct dma_interleaved_template *xt, + unsigned long flags); int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg); @@ -522,7 +607,7 @@ static inline int dmaengine_slave_config(struct dma_chan *chan, static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single( struct dma_chan *chan, void *buf, size_t len, - enum dma_data_direction dir, unsigned long flags) + enum dma_transfer_direction dir, unsigned long flags) { struct scatterlist sg; sg_init_one(&sg, buf, len); |