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dmaengine: dw: fix cyclic transfer setup

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Commit 61e183f830 ("dmaengine/dw_dmac: Reconfigure interrupt and
chan_cfg register on resume") moved some channel initialisation to
a new function which must be called before starting a transfer.

This updates dw_dma_cyclic_start() to use dwc_dostart() like the other
modes, thus ensuring dwc_initialize() gets called and removing some code
duplication.

Fixes: 61e183f830 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Cc: <stable@vger.kernel.org>
This commit is contained in:
Mans Rullgard 2016-01-11 13:04:28 +00:00 committed by Vinod Koul
parent d20313b2c4
commit df3bb8a0e6
1 changed files with 1 additions and 22 deletions
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23
drivers/dma/dw/core.c
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@ -1245,7 +1245,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
int dw_dma_cyclic_start(struct dma_chan *chan)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
struct dw_dma *dw = to_dw_dma(dwc->chan.device);
unsigned long flags;
if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) {
@ -1254,27 +1253,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
}
spin_lock_irqsave(&dwc->lock, flags);
/* Assert channel is idle */
if (dma_readl(dw, CH_EN) & dwc->mask) {
dev_err(chan2dev(&dwc->chan),
"%s: BUG: Attempted to start non-idle channel\n",
__func__);
dwc_dump_chan_regs(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
return -EBUSY;
}
dma_writel(dw, CLEAR.ERROR, dwc->mask);
dma_writel(dw, CLEAR.XFER, dwc->mask);
/* Setup DMAC channel registers */
channel_writel(dwc, LLP, dwc->cdesc->desc[0]->txd.phys);
channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
channel_writel(dwc, CTL_HI, 0);
channel_set_bit(dw, CH_EN, dwc->mask);
dwc_dostart(dwc, dwc->cdesc->desc[0]);
spin_unlock_irqrestore(&dwc->lock, flags);
return 0;