SNDRV_DEV_CMD_PRE 218 sound/core/init.c snd_device_free_all(card, SNDRV_DEV_CMD_PRE); SNDRV_DEV_CMD_PRE 411 sound/core/init.c if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {