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

Vinod Koul vinod.koul at intel.com
Thu May 30 14:15:57 EDT 2013


On Tue, May 14, 2013 at 11:03:20PM +0800, Barry Song wrote:
> From: Rongjun Ying <Rongjun.Ying at csr.com>
> 
> 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 at csr.com>
> Signed-off-by: Barry Song <Baohua.Song at csr.com>
Applied, thanks

--
~Vinod
> ---
>  drivers/dma/sirf-dma.c |   17 +++++++++++++++++
>  1 files changed, 17 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c
> index 1765a0a..716b23e 100644
> --- a/drivers/dma/sirf-dma.c
> +++ b/drivers/dma/sirf-dma.c
> @@ -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;
> -- 
> 1.7.4.1
> 

-- 



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