uaudio_signext
val = ((uaudio_signext(mc->type, val) - mc->ranges[0].minval)
Static int uaudio_signext(int, int);
r->minval = uaudio_signext(mc->type,
r->maxval = uaudio_signext(mc->type,
mc->ranges[i].minval = uaudio_signext(mc->type, minval);
mc->ranges[i].maxval = uaudio_signext(mc->type, maxval);
mc->ranges[i].resval = uaudio_signext(mc->type, resval);