commit
dd8ecfcac66b4485416b2d1df0ec4798b198d7d6 upstream.
Accordingly to discussion [1] and followed up documentation the DMA controller
driver shouldn't start any DMA operations when dmaengine_submit() is called.
This patch fixes the workflow in dw_dmac driver to follow the documentation.
[1] http://www.spinics.net/lists/arm-kernel/msg125987.html
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Cc: "Petallo, MauriceX R" <mauricex.r.petallo@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- imx-dma
- imx-sdma
- mxs-dma.c
- imx-dma
- imx-sdma
- mxs-dma.c
- intel_mid_dma
4. Check other subsystems for dma drivers and merge/move to dmaengine
5. Remove dma_slave_config's dma direction.
- intel_mid_dma
4. Check other subsystems for dma drivers and merge/move to dmaengine
5. Remove dma_slave_config's dma direction.
* possible, perhaps even appending to those already submitted
* for DMA. But this is hard to do in a race-free manner.
*/
* possible, perhaps even appending to those already submitted
* for DMA. But this is hard to do in a race-free manner.
*/
- if (list_empty(&dwc->active_list)) {
- dev_vdbg(chan2dev(tx->chan), "%s: started %u\n", __func__,
- desc->txd.cookie);
- list_add_tail(&desc->desc_node, &dwc->active_list);
- dwc_dostart(dwc, dwc_first_active(dwc));
- } else {
- dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", __func__,
- desc->txd.cookie);
- list_add_tail(&desc->desc_node, &dwc->queue);
- }
+ dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", __func__, desc->txd.cookie);
+ list_add_tail(&desc->desc_node, &dwc->queue);
spin_unlock_irqrestore(&dwc->lock, flags);
spin_unlock_irqrestore(&dwc->lock, flags);
static void dwc_issue_pending(struct dma_chan *chan)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
static void dwc_issue_pending(struct dma_chan *chan)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- if (!list_empty(&dwc->queue))
- dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
+ spin_lock_irqsave(&dwc->lock, flags);
+ if (list_empty(&dwc->active_list))
+ dwc_dostart_first_queued(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
}
static int dwc_alloc_chan_resources(struct dma_chan *chan)
}
static int dwc_alloc_chan_resources(struct dma_chan *chan)