ASoC: simple-card-utils: add asoc_simple_card_clean_reference()

simple-card needs to decrease the reference count of the device nodes.
This patch makes this method simple style standard.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/simple_card_utils.h

@@ -65,4 +65,6 @@ int asoc_simple_card_canonicalize_dailink(struct snd_soc_dai_link *dai_link);
 void asoc_simple_card_canonicalize_cpu(struct snd_soc_dai_link *dai_link,
 				      int is_single_links);
 
+int asoc_simple_card_clean_reference(struct snd_soc_card *card);
+
 #endif /* __SIMPLE_CARD_CORE_H */

sound/soc/generic/simple-card-utils.c

@@ -223,6 +223,21 @@ void asoc_simple_card_canonicalize_cpu(struct snd_soc_dai_link *dai_link,
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_canonicalize_cpu);
 
+int asoc_simple_card_clean_reference(struct snd_soc_card *card)
+{
+	struct snd_soc_dai_link *dai_link;
+	int num_links;
+
+	for (num_links = 0, dai_link = card->dai_link;
+	     num_links < card->num_links;
+	     num_links++, dai_link++) {
+		of_node_put(dai_link->cpu_of_node);
+		of_node_put(dai_link->codec_of_node);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(asoc_simple_card_clean_reference);
+
 /* Module information */
 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 MODULE_DESCRIPTION("ALSA SoC Simple Card Utils");