SNDRV_PCM_IOCTL_HWSYNC 586 include/uapi/sound/asound.h #define SNDRV_PCM_IOCTL_HWSYNC _IO('A', 0x22) SNDRV_PCM_IOCTL_HWSYNC 586 tools/include/uapi/sound/asound.h #define SNDRV_PCM_IOCTL_HWSYNC _IO('A', 0x22)