SNDRV_PCM_MMAP_OFFSET_CONTROL 321 include/uapi/sound/asound.h SNDRV_PCM_MMAP_OFFSET_CONTROL = 0x81000000, SNDRV_PCM_MMAP_OFFSET_CONTROL 321 tools/include/uapi/sound/asound.h SNDRV_PCM_MMAP_OFFSET_CONTROL = 0x81000000,