CM_PLAYBACK_SPDF
snd_cmipci_set_bit(cm, CM_REG_FUNCTRL1, CM_PLAYBACK_SPDF);
snd_cmipci_clear_bit(cm, CM_REG_FUNCTRL1, CM_PLAYBACK_SPDF);
snd_cmipci_set_bit(chip, CM_REG_FUNCTRL1, CM_PLAYBACK_SPDF);
snd_cmipci_clear_bit(chip, CM_REG_FUNCTRL1, CM_PLAYBACK_SPDF);