[PATCH v3 05/21] ASoC: ops: Introduce 'soc_set_enum_kctl'

[James Calligeros <jcalligeros99@gmail.com>]

From: Martin Povišer <povik+lin@cutebit.org>

The new function is to be used to set enumerated controls to desired
values. It is something a machine driver may call in fixup_controls.

Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
---
 include/sound/soc.h |  2 +
 sound/soc/soc-ops.c | 67 +++++++++++++++++++++++++
 2 files changed, 69 insertions(+)

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 7509824a6b2e..dcfd706a73ad 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -580,6 +580,8 @@ int snd_soc_limit_volume(struct snd_soc_card *card,
 	const char *name, int max);
 int snd_soc_ctl_activate(struct snd_soc_card *card,
 	const char *name, int active);
+int snd_soc_set_enum_kctl(struct snd_soc_card *card,
+	const char *name, const char *strval);
 int snd_soc_bytes_info(struct snd_kcontrol *kcontrol,
 		       struct snd_ctl_elem_info *uinfo);
 int snd_soc_bytes_get(struct snd_kcontrol *kcontrol,
diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c
index 295056bcc081..149a094112d2 100644
--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -503,6 +503,73 @@ int snd_soc_ctl_activate(struct snd_soc_card *card,
 }
 EXPORT_SYMBOL_GPL(snd_soc_ctl_activate);
 
+static int soc_set_enum_kctl(struct snd_kcontrol *kctl, const char *value)
+{
+	int sel, i, ret;
+
+	struct snd_ctl_elem_value *evalue __free(kfree) = kzalloc_obj(*evalue);
+	if (!evalue)
+		return -ENOMEM;
+
+	struct snd_ctl_elem_info *info __free(kfree) = kzalloc_obj(*info);
+	if (!info)
+		return -ENOMEM;
+
+	info->id = evalue->id = kctl->id;
+
+	ret = kctl->info(kctl, info);
+	if (ret < 0)
+		return ret;
+
+	if (!kctl->put)
+		return -EINVAL;
+
+	if (info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED)
+		return -EINVAL;
+
+	for (sel = 0; sel < info->value.enumerated.items; sel++) {
+		info->value.enumerated.item = sel;
+		ret = kctl->info(kctl, info);
+		if (ret < 0)
+			return ret;
+
+		if (!strcmp(value, info->value.enumerated.name))
+			break;
+	}
+
+	if (sel == info->value.enumerated.items)
+		return -ENOENT;
+
+	for (i = 0; i < info->count; i++)
+		evalue->value.enumerated.item[i] = sel;
+
+	return kctl->put(kctl, evalue);
+}
+
+/**
+ * snd_soc_set_enum_kctl - Set enumerated control matching a name
+ *
+ * @card: where to look for the controls
+ * @name: name
+ * @value: string value to set the controls to
+ *
+ * Return 0 on success, else error.
+ */
+int snd_soc_set_enum_kctl(struct snd_soc_card *card,
+			  const char *name, const char *value)
+{
+	struct snd_kcontrol *kctl;
+
+	kctl = snd_soc_card_get_kcontrol(card, name);
+	if (!kctl) {
+		dev_dbg(card->dev, "Tried to set unknown control '%s' to '%s'\n", name, value);
+		return -EINVAL;
+	}
+
+	return soc_set_enum_kctl(kctl, value);
+}
+EXPORT_SYMBOL_GPL(snd_soc_set_enum_kctl);
+
 int snd_soc_bytes_info(struct snd_kcontrol *kcontrol,
 		       struct snd_ctl_elem_info *uinfo)
 {

-- 
2.56.0