3.13.11-ckt34 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Mans Rullgard <[email protected]> commit df3bb8a0e619d501cd13334c3e0586edcdcbc716 upstream. 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 <[email protected]> Reviewed-by: Viresh Kumar <[email protected]> Signed-off-by: Vinod Koul <[email protected]> [ kamal: backport to 3.19-stable: context ] Signed-off-by: Kamal Mostafa <[email protected]> --- drivers/dma/dw/core.c | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index b24ee31..529948e 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -1209,7 +1209,6 @@ 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)) { @@ -1218,26 +1217,7 @@ 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), - "BUG: Attempted to start non-idle channel\n"); - 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; -- 1.9.1
