ASoC: mediatek: mt8183: support WoV

Add DAI link and pin muxing for wake on voice.
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20191019143504.4.Ibf012d0cd8679d846213606dc5f426aea1ff590a@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/mediatek/Kconfig

@@ -125,6 +125,7 @@ config SND_SOC_MT8183_MT6358_TS3A227E_MAX98357A
 	select SND_SOC_MAX98357A
 	select SND_SOC_BT_SCO
 	select SND_SOC_TS3A227E
+	select SND_SOC_CROS_EC_CODEC
 	help
 	  This adds ASoC driver for Mediatek MT8183 boards
 	  with the MT6358 TS3A227E MAX98357A audio codec.

sound/soc/mediatek/mt8183/mt8183-mt6358-ts3a227-max98357.c

@@ -19,11 +19,12 @@ enum PINCTRL_PIN_STATE {
 	PIN_STATE_DEFAULT = 0,
 	PIN_TDM_OUT_ON,
 	PIN_TDM_OUT_OFF,
+	PIN_WOV,
 	PIN_STATE_MAX
 };
 
 static const char * const mt8183_pin_str[PIN_STATE_MAX] = {
-	"default", "aud_tdm_out_on", "aud_tdm_out_off",
+	"default", "aud_tdm_out_on", "aud_tdm_out_off", "wov",
 };
 
 struct mt8183_mt6358_ts3a227_max98357_priv {
@@ -142,6 +143,11 @@ SND_SOC_DAILINK_DEFS(playback_hdmi,
 	DAILINK_COMP_ARRAY(COMP_DUMMY()),
 	DAILINK_COMP_ARRAY(COMP_EMPTY()));
 
+SND_SOC_DAILINK_DEFS(wake_on_voice,
+	DAILINK_COMP_ARRAY(COMP_DUMMY()),
+	DAILINK_COMP_ARRAY(COMP_DUMMY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
 /* BE */
 SND_SOC_DAILINK_DEFS(primary_codec,
 	DAILINK_COMP_ARRAY(COMP_CPU("ADDA")),
@@ -229,6 +235,41 @@ static struct snd_soc_ops mt8183_mt6358_tdm_ops = {
 	.shutdown = mt8183_mt6358_tdm_shutdown,
 };
 
+static int
+mt8183_mt6358_ts3a227_max98357_wov_startup(
+	struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_card *card = rtd->card;
+	struct mt8183_mt6358_ts3a227_max98357_priv *priv =
+			snd_soc_card_get_drvdata(card);
+
+	return pinctrl_select_state(priv->pinctrl,
+				    priv->pin_states[PIN_WOV]);
+}
+
+static void
+mt8183_mt6358_ts3a227_max98357_wov_shutdown(
+	struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_card *card = rtd->card;
+	struct mt8183_mt6358_ts3a227_max98357_priv *priv =
+			snd_soc_card_get_drvdata(card);
+	int ret;
+
+	ret = pinctrl_select_state(priv->pinctrl,
+				   priv->pin_states[PIN_STATE_DEFAULT]);
+	if (ret)
+		dev_err(card->dev, "%s failed to select state %d\n",
+			__func__, ret);
+}
+
+static const struct snd_soc_ops mt8183_mt6358_ts3a227_max98357_wov_ops = {
+	.startup = mt8183_mt6358_ts3a227_max98357_wov_startup,
+	.shutdown = mt8183_mt6358_ts3a227_max98357_wov_shutdown,
+};
+
 static struct snd_soc_dai_link
 mt8183_mt6358_ts3a227_max98357_dai_links[] = {
 	/* FE */
@@ -306,6 +347,15 @@ mt8183_mt6358_ts3a227_max98357_dai_links[] = {
 		.dpcm_playback = 1,
 		SND_SOC_DAILINK_REG(playback_hdmi),
 	},
+	{
+		.name = "Wake on Voice",
+		.stream_name = "Wake on Voice",
+		.ignore_suspend = 1,
+		.ignore = 1,
+		SND_SOC_DAILINK_REG(wake_on_voice),
+		.ops = &mt8183_mt6358_ts3a227_max98357_wov_ops,
+	},
+
 	/* BE */
 	{
 		.name = "Primary Codec",
@@ -429,7 +479,7 @@ static int
 mt8183_mt6358_ts3a227_max98357_dev_probe(struct platform_device *pdev)
 {
 	struct snd_soc_card *card = &mt8183_mt6358_ts3a227_max98357_card;
-	struct device_node *platform_node;
+	struct device_node *platform_node, *ec_codec;
 	struct snd_soc_dai_link *dai_link;
 	struct mt8183_mt6358_ts3a227_max98357_priv *priv;
 	int ret;
@@ -444,10 +494,24 @@ mt8183_mt6358_ts3a227_max98357_dev_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	ec_codec = of_parse_phandle(pdev->dev.of_node, "mediatek,ec-codec", 0);
+
 	for_each_card_prelinks(card, i, dai_link) {
 		if (dai_link->platforms->name)
 			continue;
-		dai_link->platforms->of_node = platform_node;
+
+		if (ec_codec && strcmp(dai_link->name, "Wake on Voice") == 0) {
+			dai_link->cpus[0].name = NULL;
+			dai_link->cpus[0].of_node = ec_codec;
+			dai_link->cpus[0].dai_name = NULL;
+			dai_link->codecs[0].name = NULL;
+			dai_link->codecs[0].of_node = ec_codec;
+			dai_link->codecs[0].dai_name = "Wake on Voice";
+			dai_link->platforms[0].of_node = ec_codec;
+			dai_link->ignore = 0;
+		} else {
+			dai_link->platforms->of_node = platform_node;
+		}
 	}
 
 	mt8183_mt6358_ts3a227_max98357_headset_dev.dlc.of_node =