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));} elsememset(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