sorry for this mess. Please ignore this one. My script made some mistake.

-Bryan

On Sat, Sep 27, 2008 at 9:49 PM, Bryan Wu cooloney@kernel.org wrote:

From: Cliff Cai cliff.cai@analog.com

With MMAP enabled (DMA mode) on the AD1981, there is +/- 250ms of delay between writing data to alsa and audio starts coming out of the AD1981.

Copy more data to local buffer before starting DMA

Signed-off-by: Cliff Cai cliff.cai@analog.com Signed-off-by: Bryan Wu cooloney@kernel.org

---

sound/soc/blackfin/bf5xx-ac97-pcm.c | 42 +++++++++++++++++++++++++++++----- sound/soc/blackfin/bf5xx-ac97.c | 1 - sound/soc/blackfin/bf5xx-sport.h | 2 + 3 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/sound/soc/blackfin/bf5xx-ac97-pcm.c b/sound/soc/blackfin/bf5xx-ac97-pcm.c index 51f4907..25e50d2 100644 --- a/sound/soc/blackfin/bf5xx-ac97-pcm.c +++ b/sound/soc/blackfin/bf5xx-ac97-pcm.c @@ -56,6 +56,7 @@ static void bf5xx_mmap_copy(struct snd_pcm_substream *substream, sport->tx_pos += runtime->period_size; if (sport->tx_pos >= runtime->buffer_size) sport->tx_pos %= runtime->buffer_size;

•           sport->tx_delay_pos = sport->tx_pos;
   } else {
           bf5xx_ac97_to_pcm(
                   (struct ac97_frame *)sport->rx_dma_buf + sport->rx_pos,
  

@@ -72,7 +73,15 @@ static void bf5xx_dma_irq(void *data) struct snd_pcm_substream *pcm = data; #if defined(CONFIG_SND_MMAP_SUPPORT) struct snd_pcm_runtime *runtime = pcm->runtime;

•   struct sport_device *sport = runtime->private_data;
   bf5xx_mmap_copy(pcm, runtime->period_size);
  

•   if (pcm->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  

•           if (sport->once == 0) {
  

•                   snd_pcm_period_elapsed(pcm);
  

•                   bf5xx_mmap_copy(pcm, runtime->period_size);
  

•                   sport->once = 1;
  

•           }
  

•   }
  

#endif snd_pcm_period_elapsed(pcm); } @@ -114,6 +123,10 @@ static int bf5xx_pcm_hw_params(struct snd_pcm_substream *substream,

static int bf5xx_pcm_hw_free(struct snd_pcm_substream *substream) {

•   struct snd_pcm_runtime *runtime = substream->runtime;
  

•   if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  

•   memset(runtime->dma_area, 0, runtime->buffer_size);
   snd_pcm_lib_free_pages(substream);
   return 0;
  

} @@ -127,16 +140,11 @@ static int bf5xx_pcm_prepare(struct snd_pcm_substream *substream) * SPORT working in TMD mode(include AC97). */ #if defined(CONFIG_SND_MMAP_SUPPORT)

•   size_t size = bf5xx_pcm_hardware.buffer_bytes_max
  

•                   * sizeof(struct ac97_frame) / 4;
  

•   /*clean up intermediate buffer*/
   if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  

•           memset(sport->tx_dma_buf, 0, size);
           sport_set_tx_callback(sport, bf5xx_dma_irq, substream);
           sport_config_tx_dma(sport, sport->tx_dma_buf, runtime->periods,
                   runtime->period_size * sizeof(struct ac97_frame));
   } else {
  

•           memset(sport->rx_dma_buf, 0, size);
           sport_set_rx_callback(sport, bf5xx_dma_irq, substream);
           sport_config_rx_dma(sport, sport->rx_dma_buf, runtime->periods,
                   runtime->period_size * sizeof(struct ac97_frame));
  

@@ -164,8 +172,12 @@ static int bf5xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd) pr_debug("%s enter\n", __func__); switch (cmd) { case SNDRV_PCM_TRIGGER_START:

•           if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  

•           if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  

•                   bf5xx_mmap_copy(substream, runtime->period_size);
  

•                   snd_pcm_period_elapsed(substream);
  

•                   sport->tx_delay_pos = 0;
                   sport_tx_start(sport);
  

•           }
           else
                   sport_rx_start(sport);
           break;
  

@@ -198,7 +210,7 @@ static snd_pcm_uframes_t bf5xx_pcm_pointer(struct snd_pcm_substream *substream)

#if defined(CONFIG_SND_MMAP_SUPPORT) if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)

•           curr = sport->tx_pos;
  

•           curr = sport->tx_delay_pos;
   else
           curr = sport->rx_pos;
  

#else @@ -237,6 +249,21 @@ static int bf5xx_pcm_open(struct snd_pcm_substream *substream) return ret; }

+static int bf5xx_pcm_close(struct snd_pcm_substream *substream) +{

•   struct snd_pcm_runtime *runtime = substream->runtime;
  

•   struct sport_device *sport = runtime->private_data;
  

•   pr_debug("%s enter\n", __func__);
  

•   if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  

•           sport->once = 0;
  

•           memset(sport->tx_dma_buf, 0, runtime->buffer_size * sizeof(struct ac97_frame));
  

•   } else
  

•           memset(sport->rx_dma_buf, 0, runtime->buffer_size * sizeof(struct ac97_frame));
  

•   return 0;
  

+}

#ifdef CONFIG_SND_MMAP_SUPPORT static int bf5xx_pcm_mmap(struct snd_pcm_substream *substream, struct vm_area_struct *vma) @@ -272,6 +299,7 @@ static int bf5xx_pcm_copy(struct snd_pcm_substream *substream, int channel,

struct snd_pcm_ops bf5xx_pcm_ac97_ops = { .open = bf5xx_pcm_open,

•   .close          = bf5xx_pcm_close,
   .ioctl          = snd_pcm_lib_ioctl,
   .hw_params      = bf5xx_pcm_hw_params,
   .hw_free        = bf5xx_pcm_hw_free,
  

diff --git a/sound/soc/blackfin/bf5xx-ac97.c b/sound/soc/blackfin/bf5xx-ac97.c index c782e31..5e5aafb 100644 --- a/sound/soc/blackfin/bf5xx-ac97.c +++ b/sound/soc/blackfin/bf5xx-ac97.c @@ -129,7 +129,6 @@ static void enqueue_cmd(struct snd_ac97 *ac97, __u16 addr, __u16 data) struct ac97_frame *nextwrite;

   sport_incfrag(sport, &nextfrag, 1);

•   sport_incfrag(sport, &nextfrag, 1);
  
   nextwrite = (struct ac97_frame *)(sport->tx_buf + \
                   nextfrag * sport->tx_fragsize);
  

diff --git a/sound/soc/blackfin/bf5xx-sport.h b/sound/soc/blackfin/bf5xx-sport.h index 4c16345..fcadcc0 100644 --- a/sound/soc/blackfin/bf5xx-sport.h +++ b/sound/soc/blackfin/bf5xx-sport.h @@ -123,6 +123,8 @@ struct sport_device { int rx_pos; unsigned int tx_buffer_size; unsigned int rx_buffer_size;

•   int tx_delay_pos;
  

•   int once;
  

#endif void *private_data; }; -- 1.5.6