SNDRV_TIMER_EVENT_MSTART
snd_pcm_timer_notify(substream, SNDRV_TIMER_EVENT_MSTART);
if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
if (event == SNDRV_TIMER_EVENT_MSTART ||
(1<<SNDRV_TIMER_EVENT_MSTART)|