On 04/10/2015 02:00 AM, Alexey Ignatov wrote:

Clearing VCIF read FIFO on overflow and underflow events fixes audio glitching when DMA load is high. This happened when simultaneously capturing and encoding video and audio, for example.

Signed-off-by: Alexey Ignatov lexszero@gmail.com

sound/soc/davinci/davinci-vcif.c | 60 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 56 insertions(+), 4 deletions(-)

diff --git a/sound/soc/davinci/davinci-vcif.c b/sound/soc/davinci/davinci-vcif.c index 5bee0427..0d8014e 100644 --- a/sound/soc/davinci/davinci-vcif.c +++ b/sound/soc/davinci/davinci-vcif.c @@ -45,6 +45,10 @@ } \ } while (0)

+#define DAVINCI_VC_INT_RERR_MASK \

• (DAVINCI_VC_INT_RERRUDR_MASK | \

• DAVINCI_VC_INT_RERROVF_MASK)
  

struct davinci_vcif_dev { struct davinci_vc *davinci_vc; struct davinci_pcm_dma_params dma_params[2]; @@ -87,6 +91,22 @@ static void davinci_vcif_stop(struct snd_pcm_substream *substream) writel(w, davinci_vc->base + DAVINCI_VC_CTRL); }

+static void davinci_vcif_interrupts(struct snd_pcm_substream *substream,

• int enable)
  

+{

• struct snd_soc_pcm_runtime *rtd = substream->private_data;
• struct davinci_vcif_dev *davinci_vcif_dev =

• 	snd_soc_dai_get_drvdata(rtd->cpu_dai);
  

• struct davinci_vc *davinci_vc = davinci_vcif_dev->davinci_vc;
• if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {

• writel(DAVINCI_VC_INT_RERR_MASK,
  

• 		davinci_vc->base + DAVINCI_VC_INTCLR);
  

• writel(enable ? DAVINCI_VC_INT_RERR_MASK : 0,
  

• 		davinci_vc->base + DAVINCI_VC_INTEN);
  

• }

+}

static int davinci_vcif_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) @@ -104,10 +124,6 @@ static int davinci_vcif_hw_params(struct snd_pcm_substream *substream, /* General line settings */ writel(DAVINCI_VC_CTRL_MASK, davinci_vc->base + DAVINCI_VC_CTRL);

• writel(DAVINCI_VC_INT_MASK, davinci_vc->base + DAVINCI_VC_INTCLR);

• writel(DAVINCI_VC_INT_MASK, davinci_vc->base + DAVINCI_VC_INTEN);

• w = readl(davinci_vc->base + DAVINCI_VC_CTRL);

  /* Determine xfer data type */

@@ -149,6 +165,32 @@ static int davinci_vcif_hw_params(struct snd_pcm_substream *substream, return 0; }

+static irqreturn_t davinci_vcif_irq_handler(int irq, void *data) +{

• struct davinci_vcif_dev *davinci_vcif_dev = data;
• struct davinci_vc *davinci_vc = davinci_vcif_dev->davinci_vc;
• uint32_t w;
• w = readl(davinci_vc->base + DAVINCI_VC_INTSTATUS);
• if (w & DAVINCI_VC_INT_RERR_MASK) {

• pr_debug("vc overflow or underflow occurred, resetting fifo\n");
  

• w = readl(davinci_vc->base + DAVINCI_VC_CTRL);
  

• MOD_REG_BIT(w, DAVINCI_VC_CTRL_RFIFOCL, 1);
  

• writel(w, davinci_vc->base + DAVINCI_VC_CTRL);
  

• w = readl(davinci_vc->base + DAVINCI_VC_CTRL);
  

• MOD_REG_BIT(w, DAVINCI_VC_CTRL_RFIFOCL, 0);
  

• writel(w, davinci_vc->base + DAVINCI_VC_CTRL);
  

• writel(DAVINCI_VC_INT_RERR_MASK,
  

• 		davinci_vc->base + DAVINCI_VC_INTCLR);
  

• }
• return IRQ_HANDLED;

+}

static int davinci_vcif_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) { @@ -159,10 +201,12 @@ static int davinci_vcif_trigger(struct snd_pcm_substream *substream, int cmd, case SNDRV_PCM_TRIGGER_RESUME: case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: davinci_vcif_start(substream);

• davinci_vcif_interrupts(substream, 1);
  

  break; case SNDRV_PCM_TRIGGER_STOP: case SNDRV_PCM_TRIGGER_SUSPEND: case SNDRV_PCM_TRIGGER_PAUSE_PUSH:

• davinci_vcif_interrupts(substream, 0);
  

  davinci_vcif_stop(substream); break; default:

@@ -178,6 +222,7 @@ static int davinci_vcif_startup(struct snd_pcm_substream *substream, struct davinci_vcif_dev *dev = snd_soc_dai_get_drvdata(dai);

snd_soc_dai_set_dma_data(dai, substream, dev->dma_params);

• return 0;

}

@@ -238,6 +283,13 @@ static int davinci_vcif_probe(struct platform_device *pdev)

dev_set_drvdata(&pdev->dev, davinci_vcif_dev);

• ret = devm_request_irq(&pdev->dev, IRQ_MBXINT, davinci_vcif_irq_handler,

• 	0, "vcif", davinci_vcif_dev);
  

• if (ret != 0) {

• dev_err(&pdev->dev, "could not request irq: %d\n", ret);
  

• return ret;
  

• }

I would make this optional to avoid regression if the arch patch is not present.

• ret = snd_soc_register_component(&pdev->dev, &davinci_vcif_component, &davinci_vcif_dai, 1); if (ret != 0) {