Commit 21fe3c52 authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Vinod Koul
Browse files

dma: dw_dmac: add dwc_chan_pause and dwc_chan_resume 



We will use at least the dwc_chan_resume() later.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent f5c6a7df

drivers/dma/dw_dmac.c

+22 −9
Original line number Diff line number Diff line
@@ -988,6 +988,26 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig) 
	return 0;

}



static inline void dwc_chan_pause(struct dw_dma_chan *dwc)

{

	u32 cfglo = channel_readl(dwc, CFG_LO);



	channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);

	while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))

		cpu_relax();



	dwc->paused = true;

}



static inline void dwc_chan_resume(struct dw_dma_chan *dwc)

{

	u32 cfglo = channel_readl(dwc, CFG_LO);



	channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);



	dwc->paused = false;

}



static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,

		       unsigned long arg)

{
@@ -995,18 +1015,13 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, 
	struct dw_dma		*dw = to_dw_dma(chan->device);

	struct dw_desc		*desc, *_desc;

	unsigned long		flags;

	u32			cfglo;

	LIST_HEAD(list);



	if (cmd == DMA_PAUSE) {

		spin_lock_irqsave(&dwc->lock, flags);



		cfglo = channel_readl(dwc, CFG_LO);

		channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);

		while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))

			cpu_relax();

		dwc_chan_pause(dwc);



		dwc->paused = true;

		spin_unlock_irqrestore(&dwc->lock, flags);

	} else if (cmd == DMA_RESUME) {

		if (!dwc->paused)
@@ -1014,9 +1029,7 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, 


		spin_lock_irqsave(&dwc->lock, flags);



		cfglo = channel_readl(dwc, CFG_LO);

		channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);

		dwc->paused = false;

		dwc_chan_resume(dwc);



		spin_unlock_irqrestore(&dwc->lock, flags);

	} else if (cmd == DMA_TERMINATE_ALL) {