ALSA: oxygen, virtuoso: fix exchanged L/R volumes of aux and CD inputs

The driver accidentally exchanged the left/right fields for stereo AC'97
mixer registers.  This affected only the aux and CD inputs because the
line input bypasses the AC'97 codec and the mic input is mono; cards
without AC'97 (Xonar DS/DG/HDAV Slim, HG2PCI, HiFier) were not affected.
Reported-and-tested-by: Abby Cedar <abbycedar@yahoo.com.au>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.31+ <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/oxygen/oxygen_mixer.c

@@ -618,9 +618,12 @@ static int ac97_volume_get(struct snd_kcontrol *ctl,
 	mutex_lock(&chip->mutex);
 	reg = oxygen_read_ac97(chip, codec, index);
 	mutex_unlock(&chip->mutex);
-	value->value.integer.value[0] = 31 - (reg & 0x1f);
-	if (stereo)
-		value->value.integer.value[1] = 31 - ((reg >> 8) & 0x1f);
+	if (!stereo) {
+		value->value.integer.value[0] = 31 - (reg & 0x1f);
+	} else {
+		value->value.integer.value[0] = 31 - ((reg >> 8) & 0x1f);
+		value->value.integer.value[1] = 31 - (reg & 0x1f);
+	}
 	return 0;
 }
 
@@ -636,14 +639,14 @@ static int ac97_volume_put(struct snd_kcontrol *ctl,
 
 	mutex_lock(&chip->mutex);
 	oldreg = oxygen_read_ac97(chip, codec, index);
-	newreg = oldreg;
-	newreg = (newreg & ~0x1f) |
-		(31 - (value->value.integer.value[0] & 0x1f));
-	if (stereo)
-		newreg = (newreg & ~0x1f00) |
-			((31 - (value->value.integer.value[1] & 0x1f)) << 8);
-	else
-		newreg = (newreg & ~0x1f00) | ((newreg & 0x1f) << 8);
+	if (!stereo) {
+		newreg = oldreg & ~0x1f;
+		newreg |= 31 - (value->value.integer.value[0] & 0x1f);
+	} else {
+		newreg = oldreg & ~0x1f1f;
+		newreg |= (31 - (value->value.integer.value[0] & 0x1f)) << 8;
+		newreg |= 31 - (value->value.integer.value[1] & 0x1f);
+	}
 	change = newreg != oldreg;
 	if (change)
 		oxygen_write_ac97(chip, codec, index, newreg);