diff mbox

[v2,1/2] dmaengine: dw: fix cyclic transfer setup

Message ID 1452517469-26922-2-git-send-email-mans@mansr.com (mailing list archive)
State Accepted
Headers show

Commit Message

Måns Rullgård Jan. 11, 2016, 1:04 p.m. UTC 
Commit 61e183f83069 ("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: 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume")
Signed-off-by: Mans Rullgard <mans@mansr.com>
---
Changes:
- replace duplicated code by dwc_dostart() call
---
 drivers/dma/dw/core.c | 23 +----------------------
 1 file changed, 1 insertion(+), 22 deletions(-)

Comments

Viresh Kumar Jan. 11, 2016, 2:08 p.m. UTC | #1 
On 11-01-16, 13:04, Mans Rullgard wrote:
> Commit 61e183f83069 ("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: 61e183f83069 ("dmaengine/dw_dmac: Reconfigure interrupt and chan_cfg register on resume")
> Signed-off-by: Mans Rullgard <mans@mansr.com>
> ---
> Changes:
> - replace duplicated code by dwc_dostart() call
> ---
>  drivers/dma/dw/core.c | 23 +----------------------
>  1 file changed, 1 insertion(+), 22 deletions(-)

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
diff mbox

Patch

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 7067b6ddc1db..af2b92f8501e 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -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;