ASoC: stm32: sai: simplify sync modes management

Use function of_find_device_by_node() to retrieve SAI
synchro provider device and private data.
This allows to remove registration of probed SAI
in a linked list.
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/stm/stm32_sai.c

@@ -28,16 +28,6 @@
 
 #include "stm32_sai.h"
 
-static LIST_HEAD(sync_providers);
-static DEFINE_MUTEX(sync_mutex);
-
-struct sync_provider {
-	struct list_head link;
-	struct device_node *node;
-	int  (*sync_conf)(void *data, int synco);
-	void *data;
-};
-
 static const struct stm32_sai_conf stm32_sai_conf_f4 = {
 	.version = SAI_STM32F4,
 };
@@ -70,9 +60,8 @@ static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci)
 	return 0;
 }
 
-static int stm32_sai_sync_conf_provider(void *data, int synco)
+static int stm32_sai_sync_conf_provider(struct stm32_sai_data *sai, int synco)
 {
-	struct stm32_sai_data *sai = (struct stm32_sai_data *)data;
 	u32 prev_synco;
 	int ret;
 
@@ -103,73 +92,34 @@ static int stm32_sai_sync_conf_provider(void *data, int synco)
 	return 0;
 }
 
-static int stm32_sai_set_sync_provider(struct device_node *np, int synco)
-{
-	struct sync_provider *provider;
-	int ret;
-
-	mutex_lock(&sync_mutex);
-	list_for_each_entry(provider, &sync_providers, link) {
-		if (provider->node == np) {
-			ret = provider->sync_conf(provider->data, synco);
-			mutex_unlock(&sync_mutex);
-			return ret;
-		}
-	}
-	mutex_unlock(&sync_mutex);
-
-	/* SAI sync provider not found */
-	return -ENODEV;
-}
-
-static int stm32_sai_set_sync(struct stm32_sai_data *sai,
+static int stm32_sai_set_sync(struct stm32_sai_data *sai_client,
 			      struct device_node *np_provider,
 			      int synco, int synci)
 {
+	struct platform_device *pdev = of_find_device_by_node(np_provider);
+	struct stm32_sai_data *sai_provider;
 	int ret;
 
-	/* Configure sync client */
-	stm32_sai_sync_conf_client(sai, synci);
+	if (!pdev) {
+		dev_err(&sai_client->pdev->dev,
+			"Device not found for node %s\n", np_provider->name);
+		return -ENODEV;
+	}
 
-	/* Configure sync provider */
-	ret = stm32_sai_set_sync_provider(np_provider, synco);
+	sai_provider = platform_get_drvdata(pdev);
+	if (!sai_provider) {
+		dev_err(&sai_client->pdev->dev,
+			"SAI sync provider data not found\n");
+		return -EINVAL;
+	}
 
+	/* Configure sync client */
+	ret = stm32_sai_sync_conf_client(sai_client, synci);
+	if (ret < 0)
 		return ret;
-}
-
-static int stm32_sai_sync_add_provider(struct platform_device *pdev,
-				       void *data)
-{
-	struct sync_provider *sp;
-
-	sp = devm_kzalloc(&pdev->dev, sizeof(*sp), GFP_KERNEL);
-	if (!sp)
-		return -ENOMEM;
 
-	sp->node = of_node_get(pdev->dev.of_node);
-	sp->data = data;
-	sp->sync_conf = &stm32_sai_sync_conf_provider;
-
-	mutex_lock(&sync_mutex);
-	list_add(&sp->link, &sync_providers);
-	mutex_unlock(&sync_mutex);
-
-	return 0;
-}
-
-static void stm32_sai_sync_del_provider(struct device_node *np)
-{
-	struct sync_provider *sp;
-
-	mutex_lock(&sync_mutex);
-	list_for_each_entry(sp, &sync_providers, link) {
-		if (sp->node == np) {
-			list_del(&sp->link);
-			of_node_put(sp->node);
-			break;
-		}
-	}
-	mutex_unlock(&sync_mutex);
+	/* Configure sync provider */
+	return stm32_sai_sync_conf_provider(sai_provider, synco);
 }
 
 static int stm32_sai_probe(struct platform_device *pdev)
@@ -179,7 +129,6 @@ static int stm32_sai_probe(struct platform_device *pdev)
 	struct reset_control *rst;
 	struct resource *res;
 	const struct of_device_id *of_id;
-	int ret;
 
 	sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
 	if (!sai)
@@ -231,27 +180,17 @@ static int stm32_sai_probe(struct platform_device *pdev)
 		reset_control_deassert(rst);
 	}
 
-	ret = stm32_sai_sync_add_provider(pdev, sai);
-	if (ret < 0)
-		return ret;
-	sai->set_sync = &stm32_sai_set_sync;
-
 	sai->pdev = pdev;
+	sai->set_sync = &stm32_sai_set_sync;
 	platform_set_drvdata(pdev, sai);
 
-	ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
-	if (ret < 0)
-		stm32_sai_sync_del_provider(np);
-
-	return ret;
+	return of_platform_populate(np, NULL, NULL, &pdev->dev);
 }
 
 static int stm32_sai_remove(struct platform_device *pdev)
 {
 	of_platform_depopulate(&pdev->dev);
 
-	stm32_sai_sync_del_provider(pdev->dev.of_node);
-
 	return 0;
 }