static int loopback_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct loopback_pcm *dpcm = runtime->private_data;
struct loopback_cable *cable = dpcm->cable;
int err, stream = 1 << substream->stream;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
err = loopback_check_format(cable, substream->stream);
if (err < 0)
return err;
dpcm->last_jiffies = jiffies;
dpcm->pcm_rate_shift = 0;
dpcm->last_drift = 0;
spin_lock(&cable->lock);
cable->running |= stream;
cable->pause &= ~stream;
loopback_timer_start(dpcm);
spin_unlock(&cable->lock);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
loopback_active_notify(dpcm);
break;
case SNDRV_PCM_TRIGGER_STOP:
spin_lock(&cable->lock);
cable->running &= ~stream;
cable->pause &= ~stream;
loopback_timer_stop(dpcm);
spin_unlock(&cable->lock);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
loopback_active_notify(dpcm);
break;
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
case SNDRV_PCM_TRIGGER_SUSPEND:
spin_lock(&cable->lock);
cable->pause |= stream;
loopback_timer_stop(dpcm);
spin_unlock(&cable->lock);
break;
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
case SNDRV_PCM_TRIGGER_RESUME:
spin_lock(&cable->lock);
dpcm->last_jiffies = jiffies;
cable->pause &= ~stream;
loopback_timer_start(dpcm);
spin_unlock(&cable->lock);
break;
default:
return -EINVAL;
}
return 0;
}
static void loopback_timer_function(unsigned long data)
{
struct loopback_pcm *dpcm = (struct loopback_pcm *)data;
unsigned int running;
running = loopback_pos_update(dpcm->cable);
if (running & (1 << dpcm->substream->stream)) {
loopback_timer_start(dpcm);
if (dpcm->period_update_pending) {
dpcm->period_update_pending = 0;
snd_pcm_period_elapsed(dpcm->substream);
}
}
}
static void loopback_timer_function(unsigned long data)
{
struct loopback_pcm *dpcm = (struct loopback_pcm *)data;
unsigned long flags;
spin_lock_irqsave(&dpcm->cable->lock, flags);
if (loopback_pos_update(dpcm->cable) & (1 << dpcm->substream->stream)) {
loopback_timer_start(dpcm);
if (dpcm->period_update_pending) {
dpcm->period_update_pending = 0;
spin_unlock_irqrestore(&dpcm->cable->lock, flags);
/* need to unlock before calling below */
snd_pcm_period_elapsed(dpcm->substream);
return;
}
}
spin_unlock_irqrestore(&dpcm->cable->lock, flags);
}
