diff options
| author | Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> | 2009-04-01 17:47:02 +0400 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-04-02 02:42:34 +0400 |
| commit | d9de451989a88a2003ca06e524aca4665c0c7f06 (patch) | |
| tree | a926d4ff1b73da88d5112324611a579a94e28095 /drivers/dma/dw_dmac_regs.h | |
| parent | 0f571515c332e00b3515dbe0859ceaa30ab66e00 (diff) | |
| download | linux-d9de451989a88a2003ca06e524aca4665c0c7f06.tar.xz | |
dw_dmac: add cyclic API to DW DMA driver
This patch adds a cyclic DMA interface to the DW DMA driver. This is
very useful if you want to use the DMA controller in combination with a
sound device which uses cyclic buffers.
Using a DMA channel for cyclic DMA will disable the possibility to use
it as a normal DMA engine until the user calls the cyclic free function
on the DMA channel. Also a cyclic DMA list can not be prepared if the
channel is already active.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/dw_dmac_regs.h')
| -rw-r--r-- | drivers/dma/dw_dmac_regs.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h index b252b202c5cf..13a580767031 100644 --- a/drivers/dma/dw_dmac_regs.h +++ b/drivers/dma/dw_dmac_regs.h @@ -126,6 +126,10 @@ struct dw_dma_regs { #define DW_REGLEN 0x400 +enum dw_dmac_flags { + DW_DMA_IS_CYCLIC = 0, +}; + struct dw_dma_chan { struct dma_chan chan; void __iomem *ch_regs; @@ -134,10 +138,12 @@ struct dw_dma_chan { spinlock_t lock; /* these other elements are all protected by lock */ + unsigned long flags; dma_cookie_t completed; struct list_head active_list; struct list_head queue; struct list_head free_list; + struct dw_cyclic_desc *cdesc; unsigned int descs_allocated; }; @@ -158,7 +164,6 @@ static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan) return container_of(chan, struct dw_dma_chan, chan); } - struct dw_dma { struct dma_device dma; void __iomem *regs; |