ad1848_set_channel_gain
(void) ad1848_set_channel_gain(sc, AD1848_DAC_CHANNEL, &vol_mid);
(void) ad1848_set_channel_gain(sc, AD1848_MONITOR_CHANNEL, &vol_0);
(void) ad1848_set_channel_gain(sc, AD1848_AUX1_CHANNEL, &vol_mid);
(void) ad1848_set_channel_gain(sc, AD1848_AUX2_CHANNEL, &vol_mid);
(void) ad1848_set_channel_gain(sc, AD1848_LINE_CHANNEL, &vol_mid);
(void) ad1848_set_channel_gain(sc, AD1848_MONO_CHANNEL, &vol_0);
(void) ad1848_set_channel_gain(sc, AD1848_AUX2_CHANNEL, &vol_0);
error = ad1848_set_channel_gain(ac, dev, &vol);
int ad1848_set_channel_gain(struct ad1848_softc *, int, struct ad1848_volume *);