ALSA: hda/realtek - Fix dock line-out volume on Dell Precision 7520

The dock line-out pin (NID 0x17 of ALC3254 codec) on Dell Precision
7520 may route to three different DACs, 0x02, 0x03 and 0x06.  The
first two DACS have the volume amp controls while the last one
doesn't.  And unfortunately, the auto-parser assigns this pin to DAC3,
resulting in the non-working volume control for the line out.

Fix it by disabling the routing to DAC3 on the corresponding pin.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199029
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -5274,6 +5274,16 @@ static void alc298_fixup_speaker_volume(struct hda_codec *codec,
 	}
 }
 
+/* disable DAC3 (0x06) selection on NID 0x17 as it has no volume amp control */
+static void alc295_fixup_disable_dac3(struct hda_codec *codec,
+				      const struct hda_fixup *fix, int action)
+{
+	if (action == HDA_FIXUP_ACT_PRE_PROBE) {
+		hda_nid_t conn[2] = { 0x02, 0x03 };
+		snd_hda_override_conn_list(codec, 0x17, 2, conn);
+	}
+}
+
 /* Hook to update amp GPIO4 for automute */
 static void alc280_hp_gpio4_automute_hook(struct hda_codec *codec,
 					  struct hda_jack_callback *jack)
@@ -5466,6 +5476,7 @@ enum {
 	ALC233_FIXUP_LENOVO_LINE2_MIC_HOTKEY,
 	ALC255_FIXUP_DELL_SPK_NOISE,
 	ALC225_FIXUP_DELL1_MIC_NO_PRESENCE,
+	ALC295_FIXUP_DISABLE_DAC3,
 	ALC280_FIXUP_HP_HEADSET_MIC,
 	ALC221_FIXUP_HP_FRONT_MIC,
 	ALC292_FIXUP_TPT460,
@@ -6200,6 +6211,10 @@ static const struct hda_fixup alc269_fixups[] = {
 		.chained = true,
 		.chain_id = ALC298_FIXUP_DELL_AIO_MIC_NO_PRESENCE,
 	},
+	[ALC295_FIXUP_DISABLE_DAC3] = {
+		.type = HDA_FIXUP_FUNC,
+		.v.func = alc295_fixup_disable_dac3,
+	},
 	[ALC256_FIXUP_DELL_INSPIRON_7559_SUBWOOFER] = {
 		.type = HDA_FIXUP_PINS,
 		.v.pins = (const struct hda_pintbl[]) {
@@ -6390,6 +6405,7 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x1028, 0x0725, "Dell Inspiron 3162", ALC255_FIXUP_DELL_SPK_NOISE),
 	SND_PCI_QUIRK(0x1028, 0x075b, "Dell XPS 13 9360", ALC256_FIXUP_DELL_XPS_13_HEADPHONE_NOISE),
 	SND_PCI_QUIRK(0x1028, 0x075d, "Dell AIO", ALC298_FIXUP_SPK_VOLUME),
+	SND_PCI_QUIRK(0x1028, 0x07b0, "Dell Precision 7520", ALC295_FIXUP_DISABLE_DAC3),
 	SND_PCI_QUIRK(0x1028, 0x0798, "Dell Inspiron 17 7000 Gaming", ALC256_FIXUP_DELL_INSPIRON_7559_SUBWOOFER),
 	SND_PCI_QUIRK(0x1028, 0x080c, "Dell WYSE", ALC225_FIXUP_DELL_WYSE_MIC_NO_PRESENCE),
 	SND_PCI_QUIRK(0x1028, 0x082a, "Dell XPS 13 9360", ALC256_FIXUP_DELL_XPS_13_HEADPHONE_NOISE),