dmaengine: dw: Reset DRAIN bit when resume the channel

For Intel iDMA 32-bit the channel can be drained on a suspend.
We need to reset the bit on the resume to return a status quo.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 8a581d8..6a23203 100644 (file)
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -846,11 +846,11 @@ static int dwc_pause(struct dma_chan *chan)
        return 0;
 }
 
-static inline void dwc_chan_resume(struct dw_dma_chan *dwc)
+static inline void dwc_chan_resume(struct dw_dma_chan *dwc, bool drain)
 {
-       u32 cfglo = channel_readl(dwc, CFG_LO);
+       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
 
-       channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+       dw->resume_chan(dwc, drain);
 
        clear_bit(DW_DMA_IS_PAUSED, &dwc->flags);
 }
@@ -863,7 +863,7 @@ static int dwc_resume(struct dma_chan *chan)
        spin_lock_irqsave(&dwc->lock, flags);
 
        if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags))
-               dwc_chan_resume(dwc);
+               dwc_chan_resume(dwc, false);
 
        spin_unlock_irqrestore(&dwc->lock, flags);
 
@@ -886,7 +886,7 @@ static int dwc_terminate_all(struct dma_chan *chan)
 
        dwc_chan_disable(dw, dwc);
 
-       dwc_chan_resume(dwc);
+       dwc_chan_resume(dwc, true);
 
        /* active_list entries will end up before queued entries */
        list_splice_init(&dwc->queue, &list);

diff --git a/drivers/dma/dw/dw.c b/drivers/dma/dw/dw.c
index 977aa28..156088f 100644 (file)
--- a/drivers/dma/dw/dw.c
+++ b/drivers/dma/dw/dw.c
@@ -35,6 +35,13 @@ static void dw_dma_suspend_chan(struct dw_dma_chan *dwc, bool drain)
        channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
 }
 
+static void dw_dma_resume_chan(struct dw_dma_chan *dwc, bool drain)
+{
+       u32 cfglo = channel_readl(dwc, CFG_LO);
+
+       channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+}
+
 static u32 dw_dma_bytes2block(struct dw_dma_chan *dwc,
                              size_t bytes, unsigned int width, size_t *len)
 {
@@ -91,6 +98,7 @@ int dw_dma_probe(struct dw_dma_chip *chip)
        /* Channel operations */
        dw->initialize_chan = dw_dma_initialize_chan;
        dw->suspend_chan = dw_dma_suspend_chan;
+       dw->resume_chan = dw_dma_resume_chan;
        dw->encode_maxburst = dw_dma_encode_maxburst;
        dw->bytes2block = dw_dma_bytes2block;
        dw->block2bytes = dw_dma_block2bytes;

diff --git a/drivers/dma/dw/idma32.c b/drivers/dma/dw/idma32.c
index 8707830..cd23b92 100644 (file)
--- a/drivers/dma/dw/idma32.c
+++ b/drivers/dma/dw/idma32.c
@@ -34,12 +34,20 @@ static void idma32_suspend_chan(struct dw_dma_chan *dwc, bool drain)
 
        if (drain)
                cfglo |= IDMA32C_CFGL_CH_DRAIN;
-       else
-               cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
 
        channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
 }
 
+static void idma32_resume_chan(struct dw_dma_chan *dwc, bool drain)
+{
+       u32 cfglo = channel_readl(dwc, CFG_LO);
+
+       if (drain)
+               cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
+
+       channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+}
+
 static u32 idma32_bytes2block(struct dw_dma_chan *dwc,
                              size_t bytes, unsigned int width, size_t *len)
 {
@@ -117,6 +125,7 @@ int idma32_dma_probe(struct dw_dma_chip *chip)
        /* Channel operations */
        dw->initialize_chan = idma32_initialize_chan;
        dw->suspend_chan = idma32_suspend_chan;
+       dw->resume_chan = idma32_resume_chan;
        dw->encode_maxburst = idma32_encode_maxburst;
        dw->bytes2block = idma32_bytes2block;
        dw->block2bytes = idma32_block2bytes;

diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index 66aa8b2..6cf299f 100644 (file)
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -315,6 +315,7 @@ struct dw_dma {
        /* Channel operations */
        void    (*initialize_chan)(struct dw_dma_chan *dwc);
        void    (*suspend_chan)(struct dw_dma_chan *dwc, bool drain);
+       void    (*resume_chan)(struct dw_dma_chan *dwc, bool drain);
        void    (*encode_maxburst)(struct dw_dma_chan *dwc, u32 *maxburst);
        u32     (*bytes2block)(struct dw_dma_chan *dwc, size_t bytes,
                               unsigned int width, size_t *len);