ASoC: core: add snd_soc_of_parse_audio_prefix()

Current ASoC can add name_prefix for DAPM, and it is necessary for
route settings. This patch adds snd_soc_of_parse_audio_prefix() for
this purpose. It will be used with snd_soc_of_parse_audio_routing().

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Keita Kobayashi <keita.kobayashi.ym@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc.h

@@ -1604,6 +1604,10 @@ int snd_soc_of_parse_audio_simple_widgets(struct snd_soc_card *card,
 int snd_soc_of_parse_tdm_slot(struct device_node *np,
 			      unsigned int *slots,
 			      unsigned int *slot_width);
+void snd_soc_of_parse_audio_prefix(struct snd_soc_card *card,
+				   struct snd_soc_codec_conf *codec_conf,
+				   struct device_node *of_node,
+				   const char *propname);
 int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
 				   const char *propname);
 unsigned int snd_soc_of_parse_daifmt(struct device_node *np,

sound/soc/soc-core.c

@@ -3303,6 +3303,26 @@ int snd_soc_of_parse_tdm_slot(struct device_node *np,
 }
 EXPORT_SYMBOL_GPL(snd_soc_of_parse_tdm_slot);
 
+void snd_soc_of_parse_audio_prefix(struct snd_soc_card *card,
+				   struct snd_soc_codec_conf *codec_conf,
+				   struct device_node *of_node,
+				   const char *propname)
+{
+	struct device_node *np = card->dev->of_node;
+	const char *str;
+	int ret;
+
+	ret = of_property_read_string(np, propname, &str);
+	if (ret < 0) {
+		/* no prefix is not error */
+		return;
+	}
+
+	codec_conf->of_node	= of_node;
+	codec_conf->name_prefix	= str;
+}
+EXPORT_SYMBOL_GPL(snd_soc_of_parse_audio_prefix);
+
 int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
 				   const char *propname)
 {