/* callbacks */
-void snd_rawmidi_receive_reset(struct snd_rawmidi_substream *substream);
int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
const unsigned char *buffer, int count);
-void snd_rawmidi_transmit_reset(struct snd_rawmidi_substream *substream);
int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
unsigned char *buffer, int count);