diff options
author | Laxman Dewangan <ldewangan@nvidia.com> | 2012-07-02 13:52:07 +0530 |
---|---|---|
committer | Vinod Koul <vinod.koul@linux.intel.com> | 2012-07-13 08:49:54 +0530 |
commit | 4a46ba36e25dcff1d30eb1681135c3c10af71c16 (patch) | |
tree | 8003546e61cd4337b5f27001bab7854cefcfe8bc /drivers/dma | |
parent | 46fb3f8ef5bde1325b1e58867a3a98dd746511d7 (diff) |
dma: tegra: fix residual calculation for cyclic case
In cyclic mode of DMA, the byte transferred can be more
than the requested size and in this case, calculating
residuals based on the current position of DMA transfer to
bytes requested i.e. bytes required to transfer to reach
bytes requested from current DMA position.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Diffstat (limited to 'drivers/dma')
-rw-r--r-- | drivers/dma/tegra20-apb-dma.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index c0836a7a863..8e0ea2438ce 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -731,6 +731,7 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, struct tegra_dma_sg_req *sg_req; enum dma_status ret; unsigned long flags; + unsigned int residual; spin_lock_irqsave(&tdc->lock, flags); @@ -744,9 +745,10 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, /* Check on wait_ack desc status */ list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { if (dma_desc->txd.cookie == cookie) { - dma_set_residue(txstate, - dma_desc->bytes_requested - - dma_desc->bytes_transferred); + residual = dma_desc->bytes_requested - + (dma_desc->bytes_transferred % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); ret = dma_desc->dma_status; spin_unlock_irqrestore(&tdc->lock, flags); return ret; @@ -757,9 +759,10 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, list_for_each_entry(sg_req, &tdc->pending_sg_req, node) { dma_desc = sg_req->dma_desc; if (dma_desc->txd.cookie == cookie) { - dma_set_residue(txstate, - dma_desc->bytes_requested - - dma_desc->bytes_transferred); + residual = dma_desc->bytes_requested - + (dma_desc->bytes_transferred % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); ret = dma_desc->dma_status; spin_unlock_irqrestore(&tdc->lock, flags); return ret; |