rfcomm_send_msc
rfcomm_send_msc(s, 1, dlci, d->v24_sig);
rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
rfcomm_send_msc(s, 0, dlci, msc->v24_sig);
rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
static int rfcomm_send_msc(struct rfcomm_session *s, int cr, u8 dlci, u8 v24_sig);