ALSA: core: Re-add snd_device_disconnect()

Revive snd_device_disconnect() again so that it can be called from the
individual driver.  This time, HD-audio will need it.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/core.h

@@ -278,7 +278,8 @@ int snd_device_new(struct snd_card *card, enum snd_device_type type,
 		   void *device_data, struct snd_device_ops *ops);
 int snd_device_register(struct snd_card *card, void *device_data);
 int snd_device_register_all(struct snd_card *card);
-int snd_device_disconnect_all(struct snd_card *card);
+void snd_device_disconnect(struct snd_card *card, void *device_data);
+void snd_device_disconnect_all(struct snd_card *card);
 void snd_device_free(struct snd_card *card, void *device_data);
 void snd_device_free_all(struct snd_card *card);
 

sound/core/device.c

@@ -73,7 +73,7 @@ int snd_device_new(struct snd_card *card, enum snd_device_type type,
 }
 EXPORT_SYMBOL(snd_device_new);
 
-static int __snd_device_disconnect(struct snd_device *dev)
+static void __snd_device_disconnect(struct snd_device *dev)
 {
 	if (dev->state == SNDRV_DEV_REGISTERED) {
 		if (dev->ops->dev_disconnect &&
@@ -81,7 +81,6 @@ static int __snd_device_disconnect(struct snd_device *dev)
 			dev_err(dev->card->dev, "device disconnect failure\n");
 		dev->state = SNDRV_DEV_DISCONNECTED;
 	}
-	return 0;
 }
 
 static void __snd_device_free(struct snd_device *dev)
@@ -108,6 +107,34 @@ static struct snd_device *look_for_dev(struct snd_card *card, void *device_data)
 	return NULL;
 }
 
+/**
+ * snd_device_disconnect - disconnect the device
+ * @card: the card instance
+ * @device_data: the data pointer to disconnect
+ *
+ * Turns the device into the disconnection state, invoking
+ * dev_disconnect callback, if the device was already registered.
+ *
+ * Usually called from snd_card_disconnect().
+ *
+ * Return: Zero if successful, or a negative error code on failure or if the
+ * device not found.
+ */
+void snd_device_disconnect(struct snd_card *card, void *device_data)
+{
+	struct snd_device *dev;
+
+	if (snd_BUG_ON(!card || !device_data))
+		return;
+	dev = look_for_dev(card, device_data);
+	if (dev)
+		__snd_device_disconnect(dev);
+	else
+		dev_dbg(card->dev, "device disconnect %p (from %pF), not found\n",
+			device_data, __builtin_return_address(0));
+}
+EXPORT_SYMBOL_GPL(snd_device_disconnect);
+
 /**
  * snd_device_free - release the device from the card
  * @card: the card instance
@@ -195,18 +222,14 @@ int snd_device_register_all(struct snd_card *card)
  * disconnect all the devices on the card.
  * called from init.c
  */
-int snd_device_disconnect_all(struct snd_card *card)
+void snd_device_disconnect_all(struct snd_card *card)
 {
 	struct snd_device *dev;
-	int err = 0;
 
 	if (snd_BUG_ON(!card))
-		return -ENXIO;
-	list_for_each_entry_reverse(dev, &card->devices, list) {
-		if (__snd_device_disconnect(dev) < 0)
-			err = -ENXIO;
-	}
-	return err;
+		return;
+	list_for_each_entry_reverse(dev, &card->devices, list)
+		__snd_device_disconnect(dev);
 }
 
 /*

sound/core/init.c

@@ -400,7 +400,6 @@ static const struct file_operations snd_shutdown_f_ops =
 int snd_card_disconnect(struct snd_card *card)
 {
 	struct snd_monitor_file *mfile;
-	int err;
 
 	if (!card)
 		return -EINVAL;
@@ -445,9 +444,7 @@ int snd_card_disconnect(struct snd_card *card)
 #endif
 
 	/* notify all devices that we are disconnected */
-	err = snd_device_disconnect_all(card);
-	if (err < 0)
-		dev_err(card->dev, "not all devices for card %i can be disconnected\n", card->number);
+	snd_device_disconnect_all(card);
 
 	snd_info_card_disconnect(card);
 	if (card->registered) {