[ALSA] hda: 92HD73xxx distortion fix

Fixed issue on some laptops that if the Master mixer and DAC mixers are
turned all the way up that will cause distortion. This is fixed by limiting
the max volume with the volume knob nid.
Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_sigmatel.c

@@ -534,6 +534,25 @@ static struct hda_verb stac92hd73xx_6ch_core_init[] = {
 	{}
 };
 
+static struct hda_verb dell_eq_core_init[] = {
+	/* set master volume to max value without distortion
+	 * and direct control */
+	{ 0x1f, AC_VERB_SET_VOLUME_KNOB_CONTROL, 0xec},
+	/* setup audio connections */
+	{ 0x0d, AC_VERB_SET_CONNECT_SEL, 0x00},
+	{ 0x0a, AC_VERB_SET_CONNECT_SEL, 0x01},
+	{ 0x0f, AC_VERB_SET_CONNECT_SEL, 0x02},
+	/* setup adcs to point to mixer */
+	{ 0x20, AC_VERB_SET_CONNECT_SEL, 0x0b},
+	{ 0x21, AC_VERB_SET_CONNECT_SEL, 0x0b},
+	/* setup import muxs */
+	{ 0x28, AC_VERB_SET_CONNECT_SEL, 0x01},
+	{ 0x29, AC_VERB_SET_CONNECT_SEL, 0x01},
+	{ 0x2a, AC_VERB_SET_CONNECT_SEL, 0x01},
+	{ 0x2b, AC_VERB_SET_CONNECT_SEL, 0x00},
+	{}
+};
+
 static struct hda_verb dell_m6_core_init[] = {
 	/* set master volume and direct control */
 	{ 0x1f, AC_VERB_SET_VOLUME_KNOB_CONTROL, 0xff},
@@ -3460,17 +3479,19 @@ static int patch_stac92hd73xx(struct hda_codec *codec)
 
 	switch (spec->board_config) {
 	case STAC_DELL_M6:
-		spec->init = dell_m6_core_init;
+		spec->init = dell_eq_core_init;
 		switch (codec->subsystem_id) {
 		case 0x1028025e: /* Analog Mics */
 		case 0x1028025f:
 			stac92xx_set_config_reg(codec, 0x0b, 0x90A70170);
 			spec->num_dmics = 0;
 			break;
-		case 0x10280254: /* Digital Mics */
-		case 0x10280255:
-		case 0x10280271:
+		case 0x10280271: /* Digital Mics */
 		case 0x10280272:
+			spec->init = dell_m6_core_init;
+			/* fall-through */
+		case 0x10280254:
+		case 0x10280255:
 			stac92xx_set_config_reg(codec, 0x13, 0x90A60160);
 			spec->num_dmics = 1;
 			break;