ALSA: hda - Create virtual-master control for VIA codecs

Now let's add the missing Master control to VIA codecs.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_via.c

@@ -1308,6 +1308,31 @@ static const struct hda_pcm_stream via_pcm_digital_capture = {
 	.channels_max = 2,
 };
 
+/*
+ * slave controls for virtual master
+ */
+static const char * const via_slave_vols[] = {
+	"Front Playback Volume",
+	"Surround Playback Volume",
+	"Center Playback Volume",
+	"LFE Playback Volume",
+	"Side Playback Volume",
+	"Headphone Playback Volume",
+	"Speaker Playback Volume",
+	NULL,
+};
+
+static const char * const via_slave_sws[] = {
+	"Front Playback Switch",
+	"Surround Playback Switch",
+	"Center Playback Switch",
+	"LFE Playback Switch",
+	"Side Playback Switch",
+	"Headphone Playback Switch",
+	"Speaker Playback Switch",
+	NULL,
+};
+
 static int via_build_controls(struct hda_codec *codec)
 {
 	struct via_spec *spec = codec->spec;
@@ -1343,6 +1368,23 @@ static int via_build_controls(struct hda_codec *codec)
 			return err;
 	}
 
+	/* if we have no master control, let's create it */
+	if (!snd_hda_find_mixer_ctl(codec, "Master Playback Volume")) {
+		unsigned int vmaster_tlv[4];
+		snd_hda_set_vmaster_tlv(codec, spec->multiout.dac_nids[0],
+					HDA_OUTPUT, vmaster_tlv);
+		err = snd_hda_add_vmaster(codec, "Master Playback Volume",
+					  vmaster_tlv, via_slave_vols);
+		if (err < 0)
+			return err;
+	}
+	if (!snd_hda_find_mixer_ctl(codec, "Master Playback Switch")) {
+		err = snd_hda_add_vmaster(codec, "Master Playback Switch",
+					  NULL, via_slave_sws);
+		if (err < 0)
+			return err;
+	}
+
 	/* assign Capture Source enums to NID */
 	kctl = snd_hda_find_mixer_ctl(codec, "Input Source");
 	for (i = 0; kctl && i < kctl->count; i++) {