SEQ_CONTROL      1221 include/uapi/linux/soundcard.h #define SEQ_EXPRESSION(dev, voice, value) SEQ_CONTROL(dev, voice, CTL_EXPRESSION, value*128)
SEQ_CONTROL      1222 include/uapi/linux/soundcard.h #define SEQ_MAIN_VOLUME(dev, voice, value) SEQ_CONTROL(dev, voice, CTL_MAIN_VOLUME, (value*16383)/100)
SEQ_CONTROL      1223 include/uapi/linux/soundcard.h #define SEQ_PANNING(dev, voice, pos) SEQ_CONTROL(dev, voice, CTL_PAN, (pos+128) / 2)