SNDRV_PCM_IOCTL_TTSTAMP 488 sound/core/pcm_compat.c case SNDRV_PCM_IOCTL_TTSTAMP: SNDRV_PCM_IOCTL_TTSTAMP 2508 sound/core/pcm_native.c case SNDRV_PCM_IOCTL_TTSTAMP: