ALSA: fireworks: cease from delayed card registration

The delayed registration of sound card instance brings less benefit than
complication of kobject management. This commit ceases from it.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210607081250.13397-3-o-takashi@sakamocchi.jpSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/fireworks/fireworks.c

@@ -194,19 +194,19 @@ efw_card_free(struct snd_card *card)
 
 	snd_efw_stream_destroy_duplex(efw);
 	snd_efw_transaction_remove_instance(efw);
+
+	mutex_destroy(&efw->mutex);
+	fw_unit_put(efw->unit);
 }
 
-static void
-do_registration(struct work_struct *work)
+static int efw_probe(struct fw_unit *unit, const struct ieee1394_device_id *entry)
 {
-	struct snd_efw *efw = container_of(work, struct snd_efw, dwork.work);
 	unsigned int card_index;
+	struct snd_card *card;
+	struct snd_efw *efw;
 	int err;
 
-	if (efw->registered)
-		return;
-
-	/* check registered cards */
+	// check registered cards.
 	mutex_lock(&devices_mutex);
 	for (card_index = 0; card_index < SNDRV_CARDS; ++card_index) {
 		if (!test_bit(card_index, devices_used) && enable[card_index])
@@ -214,26 +214,32 @@ do_registration(struct work_struct *work)
 	}
 	if (card_index >= SNDRV_CARDS) {
 		mutex_unlock(&devices_mutex);
-		return;
+		return -ENOENT;
 	}
 
-	err = snd_card_new(&efw->unit->device, index[card_index],
-			   id[card_index], THIS_MODULE, 0, &efw->card);
+	err = snd_card_new(&unit->device, index[card_index], id[card_index], THIS_MODULE,
+			   sizeof(*efw), &card);
 	if (err < 0) {
 		mutex_unlock(&devices_mutex);
-		return;
+		return err;
 	}
+	card->private_free = efw_card_free;
 	set_bit(card_index, devices_used);
 	mutex_unlock(&devices_mutex);
 
-	efw->card->private_free = efw_card_free;
-	efw->card->private_data = efw;
+	efw = card->private_data;
+	efw->unit = fw_unit_get(unit);
+	dev_set_drvdata(&unit->device, efw);
+	efw->card = card;
+	efw->card_index = card_index;
+
+	mutex_init(&efw->mutex);
+	spin_lock_init(&efw->lock);
+	init_waitqueue_head(&efw->hwdep_wait);
 
-	/* prepare response buffer */
-	snd_efw_resp_buf_size = clamp(snd_efw_resp_buf_size,
-				      SND_EFW_RESPONSE_MAXIMUM_BYTES, 4096U);
-	efw->resp_buf = devm_kzalloc(&efw->card->card_dev,
-				     snd_efw_resp_buf_size, GFP_KERNEL);
+	// prepare response buffer.
+	snd_efw_resp_buf_size = clamp(snd_efw_resp_buf_size, SND_EFW_RESPONSE_MAXIMUM_BYTES, 4096U);
+	efw->resp_buf = devm_kzalloc(&card->card_dev, snd_efw_resp_buf_size, GFP_KERNEL);
 	if (!efw->resp_buf) {
 		err = -ENOMEM;
 		goto error;
@@ -265,80 +271,33 @@ do_registration(struct work_struct *work)
 	if (err < 0)
 		goto error;
 
-	err = snd_card_register(efw->card);
+	err = snd_card_register(card);
 	if (err < 0)
 		goto error;
 
-	efw->registered = true;
-
-	return;
-error:
-	snd_card_free(efw->card);
-	dev_info(&efw->unit->device,
-		 "Sound card registration failed: %d\n", err);
-}
-
-static int
-efw_probe(struct fw_unit *unit, const struct ieee1394_device_id *entry)
-{
-	struct snd_efw *efw;
-
-	efw = devm_kzalloc(&unit->device, sizeof(struct snd_efw), GFP_KERNEL);
-	if (efw == NULL)
-		return -ENOMEM;
-	efw->unit = fw_unit_get(unit);
-	dev_set_drvdata(&unit->device, efw);
-
-	mutex_init(&efw->mutex);
-	spin_lock_init(&efw->lock);
-	init_waitqueue_head(&efw->hwdep_wait);
-
-	/* Allocate and register this sound card later. */
-	INIT_DEFERRABLE_WORK(&efw->dwork, do_registration);
-	snd_fw_schedule_registration(unit, &efw->dwork);
-
 	return 0;
+error:
+	snd_card_free(card);
+	return err;
 }
 
 static void efw_update(struct fw_unit *unit)
 {
 	struct snd_efw *efw = dev_get_drvdata(&unit->device);
 
-	/* Postpone a workqueue for deferred registration. */
-	if (!efw->registered)
-		snd_fw_schedule_registration(unit, &efw->dwork);
-
 	snd_efw_transaction_bus_reset(efw->unit);
 
-	/*
-	 * After registration, userspace can start packet streaming, then this
-	 * code block works fine.
-	 */
-	if (efw->registered) {
-		mutex_lock(&efw->mutex);
-		snd_efw_stream_update_duplex(efw);
-		mutex_unlock(&efw->mutex);
-	}
+	mutex_lock(&efw->mutex);
+	snd_efw_stream_update_duplex(efw);
+	mutex_unlock(&efw->mutex);
 }
 
 static void efw_remove(struct fw_unit *unit)
 {
 	struct snd_efw *efw = dev_get_drvdata(&unit->device);
 
-	/*
-	 * Confirm to stop the work for registration before the sound card is
-	 * going to be released. The work is not scheduled again because bus
-	 * reset handler is not called anymore.
-	 */
-	cancel_delayed_work_sync(&efw->dwork);
-
-	if (efw->registered) {
-		// Block till all of ALSA character devices are released.
-		snd_card_free(efw->card);
-	}
-
-	mutex_destroy(&efw->mutex);
-	fw_unit_put(efw->unit);
+	// Block till all of ALSA character devices are released.
+	snd_card_free(efw->card);
 }
 
 static const struct ieee1394_device_id efw_id_table[] = {

sound/firewire/fireworks/fireworks.h

@@ -65,9 +65,6 @@ struct snd_efw {
 	struct mutex mutex;
 	spinlock_t lock;
 
-	bool registered;
-	struct delayed_work dwork;
-
 	/* for transaction */
 	u32 seqnum;
 	bool resp_addr_changable;