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dmaengine: sirf: set dma residue based on the current dma transfer position

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read SIRFSOC_DMA_CH_ADDR register to get current dma transfer position, then
update dma residue so that things like ALSA drivers work as ALSA drivers need
the right residue value.

Signed-off-by: Rongjun Ying <Rongjun.Ying@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Rongjun Ying 2013-05-14 23:03:20 +08:00 committed by Vinod Koul
parent 7bdc1e272a
commit add93b578e
1 changed files with 17 additions and 0 deletions
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17
drivers/dma/sirf-dma.c
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@ -466,12 +466,29 @@ static enum dma_status
sirfsoc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
unsigned long flags;
enum dma_status ret;
struct sirfsoc_dma_desc *sdesc;
int cid = schan->chan.chan_id;
unsigned long dma_pos;
unsigned long dma_request_bytes;
unsigned long residue;
spin_lock_irqsave(&schan->lock, flags);
sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
node);
dma_request_bytes = (sdesc->xlen + 1) * (sdesc->ylen + 1) *
(sdesc->width * SIRFSOC_DMA_WORD_LEN);
ret = dma_cookie_status(chan, cookie, txstate);
dma_pos = readl_relaxed(sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR)
<< 2;
residue = dma_request_bytes - (dma_pos - sdesc->addr);
dma_set_residue(txstate, residue);
spin_unlock_irqrestore(&schan->lock, flags);
return ret;