amixer_set_y
amixer_set_y(amixer, scale);
.set_scale = amixer_set_y,
hw->amixer_set_y(amixer->rsc.ctrl_blk, y);
int (*amixer_set_y)(void *blk, unsigned int y);
.amixer_set_y = amixer_set_y,
.amixer_set_y = amixer_set_y,