ASoC: core: Add snd_soc_card_get_kcontrol()

This is useful for drivers who want to grab a pointer to
snd_kcontrol outside of the kcontrol callbacks.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

include/sound/soc.h

@@ -475,6 +475,8 @@ int snd_soc_set_ac97_ops(struct snd_ac97_bus_ops *ops);
 struct snd_kcontrol *snd_soc_cnew(const struct snd_kcontrol_new *_template,
 				  void *data, const char *long_name,
 				  const char *prefix);
+struct snd_kcontrol *snd_soc_card_get_kcontrol(struct snd_soc_card *soc_card,
+					       const char *name);
 int snd_soc_add_codec_controls(struct snd_soc_codec *codec,
 	const struct snd_kcontrol_new *controls, int num_controls);
 int snd_soc_add_platform_controls(struct snd_soc_platform *platform,

sound/soc/soc-core.c

@@ -2299,6 +2299,22 @@ static int snd_soc_add_controls(struct snd_card *card, struct device *dev,
 	return 0;
 }
 
+struct snd_kcontrol *snd_soc_card_get_kcontrol(struct snd_soc_card *soc_card,
+					       const char *name)
+{
+	struct snd_card *card = soc_card->snd_card;
+	struct snd_kcontrol *kctl;
+
+	if (unlikely(!name))
+		return NULL;
+
+	list_for_each_entry(kctl, &card->controls, list)
+		if (!strncmp(kctl->id.name, name, sizeof(kctl->id.name)))
+			return kctl;
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(snd_soc_card_get_kcontrol);
+
 /**
  * snd_soc_add_codec_controls - add an array of controls to a codec.
  * Convenience function to add a list of controls. Many codecs were