ASoC: Define soc_add_dai() to add a DAI to a component

Define soc_add_dai() as a wrapper to add a single DAI to a component.
It can be reused to register a DAI dynamically by topology.
Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/soc-core.c

@@ -2744,36 +2744,19 @@ static void snd_soc_unregister_dais(struct snd_soc_component *component)
 	}
 }
 
-/**
- * snd_soc_register_dais - Register a DAI with the ASoC core
- *
- * @component: The component the DAIs are registered for
- * @dai_drv: DAI driver to use for the DAIs
- * @count: Number of DAIs
- * @legacy_dai_naming: Use the legacy naming scheme and let the DAI inherit the
- *                     parent's name.
- */
-static int snd_soc_register_dais(struct snd_soc_component *component,
-	struct snd_soc_dai_driver *dai_drv, size_t count,
+/* Create a DAI and add it to the component's DAI list */
+static struct snd_soc_dai *soc_add_dai(struct snd_soc_component *component,
+	struct snd_soc_dai_driver *dai_drv,
 	bool legacy_dai_naming)
 {
 	struct device *dev = component->dev;
 	struct snd_soc_dai *dai;
-	unsigned int i;
-	int ret;
 
-	dev_dbg(dev, "ASoC: dai register %s #%Zu\n", dev_name(dev), count);
-
-	component->dai_drv = dai_drv;
-	component->num_dai = count;
-
-	for (i = 0; i < count; i++) {
+	dev_dbg(dev, "ASoC: dynamically register DAI %s\n", dev_name(dev));
 
 	dai = kzalloc(sizeof(struct snd_soc_dai), GFP_KERNEL);
-		if (dai == NULL) {
-			ret = -ENOMEM;
-			goto err;
-		}
+	if (dai == NULL)
+		return NULL;
 
 	/*
 	 * Back in the old days when we still had component-less DAIs,
@@ -2783,31 +2766,64 @@ static int snd_soc_register_dais(struct snd_soc_component *component,
 	 * the same naming style even though those DAIs are not
 	 * component-less anymore.
 	 */
-		if (count == 1 && legacy_dai_naming &&
-			(dai_drv[i].id == 0 || dai_drv[i].name == NULL)) {
+	if (legacy_dai_naming &&
+	   (dai_drv->id == 0 || dai_drv->name == NULL)) {
 		dai->name = fmt_single_name(dev, &dai->id);
 	} else {
-			dai->name = fmt_multiple_name(dev, &dai_drv[i]);
-			if (dai_drv[i].id)
-				dai->id = dai_drv[i].id;
+		dai->name = fmt_multiple_name(dev, dai_drv);
+		if (dai_drv->id)
+			dai->id = dai_drv->id;
 		else
-				dai->id = i;
+			dai->id = component->num_dai;
 	}
 	if (dai->name == NULL) {
 		kfree(dai);
-			ret = -ENOMEM;
-			goto err;
+		return NULL;
 	}
 
 	dai->component = component;
 	dai->dev = dev;
-		dai->driver = &dai_drv[i];
+	dai->driver = dai_drv;
 	if (!dai->driver->ops)
 		dai->driver->ops = &null_dai_ops;
 
 	list_add(&dai->list, &component->dai_list);
+	component->num_dai++;
 
 	dev_dbg(dev, "ASoC: Registered DAI '%s'\n", dai->name);
+	return dai;
+}
+
+/**
+ * snd_soc_register_dais - Register a DAI with the ASoC core
+ *
+ * @component: The component the DAIs are registered for
+ * @dai_drv: DAI driver to use for the DAIs
+ * @count: Number of DAIs
+ * @legacy_dai_naming: Use the legacy naming scheme and let the DAI inherit the
+ *                     parent's name.
+ */
+static int snd_soc_register_dais(struct snd_soc_component *component,
+	struct snd_soc_dai_driver *dai_drv, size_t count,
+	bool legacy_dai_naming)
+{
+	struct device *dev = component->dev;
+	struct snd_soc_dai *dai;
+	unsigned int i;
+	int ret;
+
+	dev_dbg(dev, "ASoC: dai register %s #%Zu\n", dev_name(dev), count);
+
+	component->dai_drv = dai_drv;
+
+	for (i = 0; i < count; i++) {
+
+		dai = soc_add_dai(component, dai_drv + i,
+				count == 1 && legacy_dai_naming);
+		if (dai == NULL) {
+			ret = -ENOMEM;
+			goto err;
+		}
 	}
 
 	return 0;