SND_TSCM_QUEUE_COUNT
if (++tscm->push_pos >= SND_TSCM_QUEUE_COUNT)
tail_pos = SND_TSCM_QUEUE_COUNT;
tscm->pull_pos = tail_pos % SND_TSCM_QUEUE_COUNT;
struct snd_firewire_tascam_change queue[SND_TSCM_QUEUE_COUNT];