mixer_get_ctl
mix_ctl_t *mixer_get_ctl(struct mix_dev *, int);
cp = mixer_get_ctl(m->dev, C_VOL);
mixer_get_ctl(dp, C_SRC)->name, n ? " " : "");
cp = mixer_get_ctl(m->dev, C_VOL);
cp = mixer_get_ctl(m->dev, C_MUT);
cp = mixer_get_ctl(m->dev, C_SRC);