From 53463a8302d0c3148c4c64c034312215e76429c2 Mon Sep 17 00:00:00 2001 From: Ahmet İnan Date: Thu, 21 Feb 2008 07:55:30 +0100 Subject: [ALSA] snd-dummy - improved timing, silence on prepare MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Ahmet İnan mathematik.uni-freiburg.de> Signed-off-by: Takashi Iwai --- sound/drivers/dummy.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'sound/drivers') diff --git a/sound/drivers/dummy.c b/sound/drivers/dummy.c index a240eaeb5c62..f67f65829f3e 100644 --- a/sound/drivers/dummy.c +++ b/sound/drivers/dummy.c @@ -181,10 +181,10 @@ struct snd_dummy_pcm { struct snd_dummy *dummy; spinlock_t lock; struct timer_list timer; - unsigned int pcm_size; - unsigned int pcm_count; + unsigned int pcm_buffer_size; + unsigned int pcm_period_size; unsigned int pcm_bps; /* bytes per second */ - unsigned int pcm_jiffie; /* bytes per one jiffie */ + unsigned int pcm_hz; /* HZ */ unsigned int pcm_irq_pos; /* IRQ position */ unsigned int pcm_buf_pos; /* position in buffer */ struct snd_pcm_substream *substream; @@ -238,11 +238,15 @@ static int snd_card_dummy_pcm_prepare(struct snd_pcm_substream *substream) if (bps <= 0) return -EINVAL; dpcm->pcm_bps = bps; - dpcm->pcm_jiffie = bps / HZ; - dpcm->pcm_size = snd_pcm_lib_buffer_bytes(substream); - dpcm->pcm_count = snd_pcm_lib_period_bytes(substream); + dpcm->pcm_hz = HZ; + dpcm->pcm_buffer_size = snd_pcm_lib_buffer_bytes(substream); + dpcm->pcm_period_size = snd_pcm_lib_period_bytes(substream); dpcm->pcm_irq_pos = 0; dpcm->pcm_buf_pos = 0; + + snd_pcm_format_set_silence(runtime->format, runtime->dma_area, + bytes_to_samples(runtime, runtime->dma_bytes)); + return 0; } @@ -254,11 +258,11 @@ static void snd_card_dummy_pcm_timer_function(unsigned long data) spin_lock_irqsave(&dpcm->lock, flags); dpcm->timer.expires = 1 + jiffies; add_timer(&dpcm->timer); - dpcm->pcm_irq_pos += dpcm->pcm_jiffie; - dpcm->pcm_buf_pos += dpcm->pcm_jiffie; - dpcm->pcm_buf_pos %= dpcm->pcm_size; - if (dpcm->pcm_irq_pos >= dpcm->pcm_count) { - dpcm->pcm_irq_pos %= dpcm->pcm_count; + dpcm->pcm_irq_pos += dpcm->pcm_bps; + if (dpcm->pcm_irq_pos >= dpcm->pcm_period_size * dpcm->pcm_hz) { + dpcm->pcm_irq_pos %= dpcm->pcm_period_size * dpcm->pcm_hz; + dpcm->pcm_buf_pos += dpcm->pcm_period_size; + dpcm->pcm_buf_pos %= dpcm->pcm_buffer_size; spin_unlock_irqrestore(&dpcm->lock, flags); snd_pcm_period_elapsed(dpcm->substream); } else -- cgit v1.2.3-59-g8ed1b