topology: Use generic pointer to realloc buffer for private data

Many element types have private data. So use the generic obj pointer
instead of the type-specific pointer when reallocating the object to
accommodate the private data.

Empty private data will be overlooked.

Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

src/topology/data.c

@@ -822,44 +822,36 @@ int tplg_copy_data(struct tplg_elem *elem, struct tplg_elem *ref)
 {
 	struct snd_soc_tplg_private *priv;
 	int priv_data_size;
+	void *obj;
 
 	if (!ref)
 		return -EINVAL;
 
 	tplg_dbg("Data '%s' used by '%s'\n", ref->id, elem->id);
+	if (!ref->data || !ref->data->size) /* overlook empty private data */
+		return 0;
+
 	priv_data_size = ref->data->size;
+	obj = realloc(elem->obj,
+			elem->size + priv_data_size);
+	if (!obj)
+		return -ENOMEM;
+	elem->obj = obj;
 
 	switch (elem->type) {
 	case SND_TPLG_TYPE_MIXER:
-		elem->mixer_ctrl = realloc(elem->mixer_ctrl,
-			elem->size + priv_data_size);
-		if (!elem->mixer_ctrl)
-			return -ENOMEM;
 		priv = &elem->mixer_ctrl->priv;
 		break;
 
 	case SND_TPLG_TYPE_ENUM:
-		elem->enum_ctrl = realloc(elem->enum_ctrl,
-			elem->size + priv_data_size);
-		if (!elem->enum_ctrl)
-			return -ENOMEM;
 		priv = &elem->enum_ctrl->priv;
 		break;
 
 	case SND_TPLG_TYPE_BYTES:
-		elem->bytes_ext = realloc(elem->bytes_ext,
-			elem->size + priv_data_size);
-		if (!elem->bytes_ext)
-			return -ENOMEM;
 		priv = &elem->bytes_ext->priv;
 		break;
 
-
 	case SND_TPLG_TYPE_DAPM_WIDGET:
-		elem->widget = realloc(elem->widget,
-			elem->size + priv_data_size);
-		if (!elem->widget)
-			return -ENOMEM;
 		priv = &elem->widget->priv;
 		break;