diff --git a/sound/pci/hda/patch_via.c b/sound/pci/hda/patch_via.c
index 59a173e88128..63e4871e5d8f 100644
--- a/sound/pci/hda/patch_via.c
+++ b/sound/pci/hda/patch_via.c
@@ -35,6 +35,7 @@
 /* 2008-04-09  Lydia Wang  Add mute front speaker when HP plugin             */
 /* 2008-04-09  Lydia Wang  Add Independent HP feature                        */
 /* 2008-05-28  Lydia Wang  Add second S/PDIF Out support for VT1702	     */
+/* 2008-09-15  Logan Li    Add VT1708S Mic Boost workaround/backdoor	     */
 /*                                                                           */
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
@@ -87,6 +88,48 @@
 #define IS_VT1708S_VENDORID(x)		((x) >= 0x11060397 && (x) <= 0x11067397)
 #define IS_VT1702_VENDORID(x)		((x) >= 0x11060398 && (x) <= 0x11067398)
 
+enum VIA_HDA_CODEC {
+	UNKNOWN = -1,
+	VT1708,
+	VT1709_10CH,
+	VT1709_6CH,
+	VT1708B_8CH,
+	VT1708B_4CH,
+	VT1708S,
+	VT1702,
+	CODEC_TYPES,
+};
+
+static enum VIA_HDA_CODEC get_codec_type(u32 vendor_id)
+{
+	u16 ven_id = vendor_id >> 16;
+	u16 dev_id = vendor_id & 0xffff;
+	enum VIA_HDA_CODEC codec_type;
+
+	/* get codec type */
+	if (ven_id != 0x1106)
+		codec_type = UNKNOWN;
+	else if (dev_id >= 0x1708 && dev_id <= 0x170b)
+		codec_type = VT1708;
+	else if (dev_id >= 0xe710 && dev_id <= 0xe713)
+		codec_type = VT1709_10CH;
+	else if (dev_id >= 0xe714 && dev_id <= 0xe717)
+		codec_type = VT1709_6CH;
+	else if (dev_id >= 0xe720 && dev_id <= 0xe723)
+		codec_type = VT1708B_8CH;
+	else if (dev_id >= 0xe724 && dev_id <= 0xe727)
+		codec_type = VT1708B_4CH;
+	else if ((dev_id & 0xfff) == 0x397
+		 && (dev_id >> 12) < 8)
+		codec_type = VT1708S;
+	else if ((dev_id & 0xfff) == 0x398
+		 && (dev_id >> 12) < 8)
+		codec_type = VT1702;
+	else
+		codec_type = UNKNOWN;
+	return codec_type;
+};
+
 #define VIA_HP_EVENT		0x01
 #define VIA_GPIO_EVENT		0x02
 
@@ -102,6 +145,48 @@ enum {
 	AUTO_SEQ_SIDE
 };
 
+#define get_amp_nid(kc)	((kc)->private_value & 0xffff)
+
+/* Some VT1708S based boards gets the micboost setting wrong, so we have
+ * to apply some brute-force and re-write the TLV's by software. */
+static int mic_boost_tlv(struct snd_kcontrol *kcontrol, int op_flag,
+			 unsigned int size, unsigned int __user *_tlv)
+{
+	struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
+	hda_nid_t nid = get_amp_nid(kcontrol);
+
+	if (get_codec_type(codec->vendor_id) == VT1708S
+	    && (nid == 0x1a || nid == 0x1e)) {
+		if (size < 4 * sizeof(unsigned int))
+			return -ENOMEM;
+		if (put_user(1, _tlv))	/* SNDRV_CTL_TLVT_DB_SCALE */
+			return -EFAULT;
+		if (put_user(2 * sizeof(unsigned int), _tlv + 1))
+			return -EFAULT;
+		if (put_user(0, _tlv + 2)) /* offset = 0 */
+			return -EFAULT;
+		if (put_user(1000, _tlv + 3)) /* step size = 10 dB */
+			return -EFAULT;
+	}
+	return 0;
+}
+
+static int mic_boost_volume_info(struct snd_kcontrol *kcontrol,
+				 struct snd_ctl_elem_info *uinfo)
+{
+	struct hda_codec *codec = snd_kcontrol_chip(kcontrol);
+	hda_nid_t nid = get_amp_nid(kcontrol);
+
+	if (get_codec_type(codec->vendor_id) == VT1708S
+	    && (nid == 0x1a || nid == 0x1e)) {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+		uinfo->count = 2;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 3;
+	}
+	return 0;
+}
+
 static struct snd_kcontrol_new vt1708_control_templates[] = {
 	HDA_CODEC_VOLUME(NULL, 0, 0, 0),
 	HDA_CODEC_MUTE(NULL, 0, 0, 0),
@@ -2430,14 +2515,29 @@ static int patch_vt1708B_4ch(struct hda_codec *codec)
 
 /* Patch for VT1708S */
 
+/* VT1708S software backdoor based override for buggy hardware micboost
+ * setting */
+#define MIC_BOOST_VOLUME(xname, nid) {				\
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,		\
+	.name = xname,					\
+	.index = 0,					\
+	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |	\
+	SNDRV_CTL_ELEM_ACCESS_TLV_READ |		\
+	SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,		\
+	.info = mic_boost_volume_info,			\
+	.get = snd_hda_mixer_amp_volume_get,		\
+	.put = snd_hda_mixer_amp_volume_put,		\
+	.tlv = { .c = mic_boost_tlv },			\
+	.private_value = HDA_COMPOSE_AMP_VAL(nid, 3, 0, HDA_INPUT) }
+
 /* capture mixer elements */
 static struct snd_kcontrol_new vt1708S_capture_mixer[] = {
 	HDA_CODEC_VOLUME("Capture Volume", 0x13, 0x0, HDA_INPUT),
 	HDA_CODEC_MUTE("Capture Switch", 0x13, 0x0, HDA_INPUT),
 	HDA_CODEC_VOLUME_IDX("Capture Volume", 1, 0x14, 0x0, HDA_INPUT),
 	HDA_CODEC_MUTE_IDX("Capture Switch", 1, 0x14, 0x0, HDA_INPUT),
-	HDA_CODEC_VOLUME("Mic Boost", 0x1A, 0x0, HDA_INPUT),
-	HDA_CODEC_VOLUME("Front Mic Boost", 0x1E, 0x0, HDA_INPUT),
+	MIC_BOOST_VOLUME("Mic Boost Capture Volume", 0x1A),
+	MIC_BOOST_VOLUME("Front Mic Boost Capture Volume", 0x1E),
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		/* The multiple "Capture Source" controls confuse alsamixer
@@ -2472,6 +2572,8 @@ static struct hda_verb vt1708S_volume_init_verbs[] = {
 	/* PW9, PW10  Output enable */
 	{0x20, AC_VERB_SET_PIN_WIDGET_CONTROL, 0x40},
 	{0x21, AC_VERB_SET_PIN_WIDGET_CONTROL, 0x40},
+	/* Enable Mic Boost Volume backdoor */
+	{0x1, 0xf98, 0x1},
 	{ }
 };