ALSA: hda - Apply +5dB output amp on ASUS Zenbook UX31A

ASUS Zenbook UX31A has yet another problem -- softer output level than
others.  According to the measurement, the peak output difference
between 31A and 31E is 5dB.  As ALC269VB has a COEF for the class-D
pre-amp, let's apply it for +5dB.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -3833,6 +3833,7 @@ enum {
 	ALC269_FIXUP_ACER_AC700,
 	ALC269_FIXUP_LIMIT_INT_MIC_BOOST,
 	ALC269VB_FIXUP_ASUS_ZENBOOK,
+	ALC269VB_FIXUP_ASUS_ZENBOOK_UX31A,
 	ALC269_FIXUP_LIMIT_INT_MIC_BOOST_MUTE_LED,
 	ALC269VB_FIXUP_ORDISSIMO_EVE2,
 	ALC283_FIXUP_CHROME_BOOK,
@@ -4126,6 +4127,17 @@ static const struct hda_fixup alc269_fixups[] = {
 		.chained = true,
 		.chain_id = ALC269VB_FIXUP_DMIC,
 	},
+	[ALC269VB_FIXUP_ASUS_ZENBOOK_UX31A] = {
+		.type = HDA_FIXUP_VERBS,
+		.v.verbs = (const struct hda_verb[]) {
+			/* class-D output amp +5dB */
+			{ 0x20, AC_VERB_SET_COEF_INDEX, 0x12 },
+			{ 0x20, AC_VERB_SET_PROC_COEF, 0x2800 },
+			{}
+		},
+		.chained = true,
+		.chain_id = ALC269VB_FIXUP_ASUS_ZENBOOK,
+	},
 	[ALC269_FIXUP_LIMIT_INT_MIC_BOOST_MUTE_LED] = {
 		.type = HDA_FIXUP_FUNC,
 		.v.func = alc269_fixup_limit_int_mic_boost,
@@ -4282,7 +4294,7 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x1043, 0x106d, "Asus K53BE", ALC269_FIXUP_LIMIT_INT_MIC_BOOST),
 	SND_PCI_QUIRK(0x1043, 0x115d, "Asus 1015E", ALC269_FIXUP_LIMIT_INT_MIC_BOOST),
 	SND_PCI_QUIRK(0x1043, 0x1427, "Asus Zenbook UX31E", ALC269VB_FIXUP_ASUS_ZENBOOK),
-	SND_PCI_QUIRK(0x1043, 0x1517, "Asus Zenbook UX31A", ALC269VB_FIXUP_ASUS_ZENBOOK),
+	SND_PCI_QUIRK(0x1043, 0x1517, "Asus Zenbook UX31A", ALC269VB_FIXUP_ASUS_ZENBOOK_UX31A),
 	SND_PCI_QUIRK(0x1043, 0x16e3, "ASUS UX50", ALC269_FIXUP_STEREO_DMIC),
 	SND_PCI_QUIRK(0x1043, 0x1a13, "Asus G73Jw", ALC269_FIXUP_ASUS_G73JW),
 	SND_PCI_QUIRK(0x1043, 0x1b13, "Asus U41SV", ALC269_FIXUP_INV_DMIC),