[ALSA] Fix stereo mutes on Surround volume control

AC97 Codec
Fix stereo mutes on Surround volume control.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ac97/ac97_codec.c

@@ -1184,7 +1184,7 @@ snd_kcontrol_t *snd_ac97_cnew(const snd_kcontrol_new_t *_template, ac97_t * ac97
 /*
  * create mute switch(es) for normal stereo controls
  */
-static int snd_ac97_cmute_new(snd_card_t *card, char *name, int reg, ac97_t *ac97)
+static int snd_ac97_cmute_new_stereo(snd_card_t *card, char *name, int reg, int check_stereo, ac97_t *ac97)
 {
 	snd_kcontrol_t *kctl;
 	int err;
@@ -1195,7 +1195,7 @@ static int snd_ac97_cmute_new(snd_card_t *card, char *name, int reg, ac97_t *ac9
 
 	mute_mask = 0x8000;
 	val = snd_ac97_read(ac97, reg);
-	if (ac97->flags & AC97_STEREO_MUTES) {
+	if (check_stereo || (ac97->flags & AC97_STEREO_MUTES)) {
 		/* check whether both mute bits work */
 		val1 = val | 0x8080;
 		snd_ac97_write(ac97, reg, val1);
@@ -1253,7 +1253,7 @@ static int snd_ac97_cvol_new(snd_card_t *card, char *name, int reg, unsigned int
 /*
  * create a mute-switch and a volume for normal stereo/mono controls
  */
-static int snd_ac97_cmix_new(snd_card_t *card, const char *pfx, int reg, ac97_t *ac97)
+static int snd_ac97_cmix_new_stereo(snd_card_t *card, const char *pfx, int reg, int check_stereo, ac97_t *ac97)
 {
 	int err;
 	char name[44];
@@ -1264,7 +1264,7 @@ static int snd_ac97_cmix_new(snd_card_t *card, const char *pfx, int reg, ac97_t
 
 	if (snd_ac97_try_bit(ac97, reg, 15)) {
 		sprintf(name, "%s Switch", pfx);
-		if ((err = snd_ac97_cmute_new(card, name, reg, ac97)) < 0)
+		if ((err = snd_ac97_cmute_new_stereo(card, name, reg, check_stereo, ac97)) < 0)
 			return err;
 	}
 	check_volume_resolution(ac97, reg, &lo_max, &hi_max);
@@ -1276,6 +1276,8 @@ static int snd_ac97_cmix_new(snd_card_t *card, const char *pfx, int reg, ac97_t
 	return 0;
 }
 
+#define snd_ac97_cmix_new(card, pfx, reg, ac97)	snd_ac97_cmix_new_stereo(card, pfx, reg, 0, ac97)
+#define snd_ac97_cmute_new(card, name, reg, ac97)	snd_ac97_cmute_new_stereo(card, name, reg, 0, ac97)
 
 static unsigned int snd_ac97_determine_spdif_rates(ac97_t *ac97);
 
@@ -1326,7 +1328,8 @@ static int snd_ac97_mixer_build(ac97_t * ac97)
 
 	/* build surround controls */
 	if (snd_ac97_try_volume_mix(ac97, AC97_SURROUND_MASTER)) {
-		if ((err = snd_ac97_cmix_new(card, "Surround Playback", AC97_SURROUND_MASTER, ac97)) < 0)
+		/* Surround Master (0x38) is with stereo mutes */
+		if ((err = snd_ac97_cmix_new_stereo(card, "Surround Playback", AC97_SURROUND_MASTER, 1, ac97)) < 0)
 			return err;
 	}