static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	if (runtime->trigger_master == NULL)
		return;
	if (runtime->trigger_master == substream) {
		if (!runtime->trigger_tstamp_latched)
			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
	} else {
		snd_pcm_trigger_tstamp(runtime->trigger_master);
		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
	}
	runtime->trigger_master = NULL;
}
static void snd_pcm_trigger_tstamp(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	if (runtime->trigger_master == NULL)
		return;
	if (runtime->trigger_master == substream) {
		if (!runtime->trigger_tstamp_latched)
			snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
	} else {
		snd_pcm_trigger_tstamp(runtime->trigger_master);
		runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp;
	}
	runtime->trigger_master = NULL;
}