sound: usb: make the USB MIDI module more independent

Remove the dependecy from the USB MIDI code on the snd_usb_audio
structure.  This allows using the USB MIDI module from another driver
without having to pretend to be the generic USB audio driver.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/usbaudio.c

@@ -2893,7 +2893,9 @@ static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
 		if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
 		     altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
 		    altsd->bInterfaceSubClass == USB_SUBCLASS_MIDI_STREAMING) {
-			if (snd_usb_create_midi_interface(chip, iface, NULL) < 0) {
+			int err = snd_usbmidi_create(chip->card, iface,
+						     &chip->midi_list, NULL);
+			if (err < 0) {
 				snd_printk(KERN_ERR "%d:%u:%d: cannot create sequencer device\n", dev->devnum, ctrlif, j);
 				continue;
 			}
@@ -3038,12 +3040,11 @@ static int create_uaxx_quirk(struct snd_usb_audio *chip,
 			.type = QUIRK_MIDI_FIXED_ENDPOINT,
 			.data = &uaxx_ep
 		};
-		if (chip->usb_id == USB_ID(0x0582, 0x002b))
-			return snd_usb_create_midi_interface(chip, iface,
-							     &ua700_quirk);
-		else
-			return snd_usb_create_midi_interface(chip, iface,
-							     &uaxx_quirk);
+		const struct snd_usb_audio_quirk *quirk =
+			chip->usb_id == USB_ID(0x0582, 0x002b)
+			? &ua700_quirk : &uaxx_quirk;
+		return snd_usbmidi_create(chip->card, iface,
+					  &chip->midi_list, quirk);
 	}
 
 	if (altsd->bNumEndpoints != 1)
@@ -3370,6 +3371,13 @@ static int audiophile_skip_setting_quirk(struct snd_usb_audio *chip,
 	return 0; /* keep this altsetting */
 }
 
+static int create_any_midi_quirk(struct snd_usb_audio *chip,
+				 struct usb_interface *intf,
+				 const struct snd_usb_audio_quirk *quirk)
+{
+	return snd_usbmidi_create(chip->card, intf, &chip->midi_list, quirk);
+}
+
 /*
  * audio-interface quirks
  *
@@ -3387,14 +3395,14 @@ static int snd_usb_create_quirk(struct snd_usb_audio *chip,
 	static const quirk_func_t quirk_funcs[] = {
 		[QUIRK_IGNORE_INTERFACE] = ignore_interface_quirk,
 		[QUIRK_COMPOSITE] = create_composite_quirk,
-		[QUIRK_MIDI_STANDARD_INTERFACE] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_FIXED_ENDPOINT] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_YAMAHA] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_MIDIMAN] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_NOVATION] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_FASTLANE] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_EMAGIC] = snd_usb_create_midi_interface,
-		[QUIRK_MIDI_CME] = snd_usb_create_midi_interface,
+		[QUIRK_MIDI_STANDARD_INTERFACE] = create_any_midi_quirk,
+		[QUIRK_MIDI_FIXED_ENDPOINT] = create_any_midi_quirk,
+		[QUIRK_MIDI_YAMAHA] = create_any_midi_quirk,
+		[QUIRK_MIDI_MIDIMAN] = create_any_midi_quirk,
+		[QUIRK_MIDI_NOVATION] = create_any_midi_quirk,
+		[QUIRK_MIDI_FASTLANE] = create_any_midi_quirk,
+		[QUIRK_MIDI_EMAGIC] = create_any_midi_quirk,
+		[QUIRK_MIDI_CME] = create_any_midi_quirk,
 		[QUIRK_AUDIO_STANDARD_INTERFACE] = create_standard_audio_quirk,
 		[QUIRK_AUDIO_FIXED_ENDPOINT] = create_fixed_stream_quirk,
 		[QUIRK_AUDIO_EDIROL_UA1000] = create_ua1000_quirk,

sound/usb/usbaudio.h

@@ -132,7 +132,6 @@ struct snd_usb_audio {
 	int pcm_devs;
 
 	struct list_head midi_list;	/* list of midi interfaces */
-	int next_midi_device;
 
 	struct list_head mixer_list;	/* list of mixer interfaces */
 };
@@ -227,8 +226,10 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
 			 int ignore_error);
 void snd_usb_mixer_disconnect(struct list_head *p);
 
-int snd_usb_create_midi_interface(struct snd_usb_audio *chip, struct usb_interface *iface,
-				  const struct snd_usb_audio_quirk *quirk);
+int snd_usbmidi_create(struct snd_card *card,
+		       struct usb_interface *iface,
+		       struct list_head *midi_list,
+		       const struct snd_usb_audio_quirk *quirk);
 void snd_usbmidi_input_stop(struct list_head* p);
 void snd_usbmidi_input_start(struct list_head* p);
 void snd_usbmidi_disconnect(struct list_head *p);

sound/usb/usx2y/us122l.c

@@ -62,8 +62,8 @@ static int us122l_create_usbmidi(struct snd_card *card)
 	struct usb_device *dev = US122L(card)->chip.dev;
 	struct usb_interface *iface = usb_ifnum_to_if(dev, 1);
 
-	return snd_usb_create_midi_interface(&US122L(card)->chip,
-					     iface, &quirk);
+	return snd_usbmidi_create(card, iface,
+				  &US122L(card)->midi_list, &quirk);
 }
 
 static int us144_create_usbmidi(struct snd_card *card)
@@ -84,8 +84,8 @@ static int us144_create_usbmidi(struct snd_card *card)
 	struct usb_device *dev = US122L(card)->chip.dev;
 	struct usb_interface *iface = usb_ifnum_to_if(dev, 0);
 
-	return snd_usb_create_midi_interface(&US122L(card)->chip,
-					     iface, &quirk);
+	return snd_usbmidi_create(card, iface,
+				  &US122L(card)->midi_list, &quirk);
 }
 
 /*
@@ -297,7 +297,7 @@ static unsigned int usb_stream_hwdep_poll(struct snd_hwdep *hw,
 static void us122l_stop(struct us122l *us122l)
 {
 	struct list_head *p;
-	list_for_each(p, &us122l->chip.midi_list)
+	list_for_each(p, &us122l->midi_list)
 		snd_usbmidi_input_stop(p);
 
 	usb_stream_stop(&us122l->sk);
@@ -363,7 +363,7 @@ static bool us122l_start(struct us122l *us122l,
 		snd_printk(KERN_ERR "us122l_start error %i \n", err);
 		goto out;
 	}
-	list_for_each(p, &us122l->chip.midi_list)
+	list_for_each(p, &us122l->midi_list)
 		snd_usbmidi_input_start(p);
 	success = true;
 out:
@@ -508,7 +508,7 @@ static bool us122l_create_card(struct snd_card *card)
 	if (err < 0) {
 /* release the midi resources */
 		struct list_head *p;
-		list_for_each(p, &us122l->chip.midi_list)
+		list_for_each(p, &us122l->midi_list)
 			snd_usbmidi_disconnect(p);
 
 		us122l_stop(us122l);
@@ -546,7 +546,7 @@ static int usx2y_create_card(struct usb_device *device, struct snd_card **cardp)
 	US122L(card)->chip.card = card;
 	mutex_init(&US122L(card)->mutex);
 	init_waitqueue_head(&US122L(card)->sk.sleep);
-	INIT_LIST_HEAD(&US122L(card)->chip.midi_list);
+	INIT_LIST_HEAD(&US122L(card)->midi_list);
 	strcpy(card->driver, "USB "NAME_ALLCAPS"");
 	sprintf(card->shortname, "TASCAM "NAME_ALLCAPS"");
 	sprintf(card->longname, "%s (%x:%x if %d at %03d/%03d)",
@@ -638,7 +638,7 @@ static void snd_us122l_disconnect(struct usb_interface *intf)
 	us122l->chip.shutdown = 1;
 
 /* release the midi resources */
-	list_for_each(p, &us122l->chip.midi_list) {
+	list_for_each(p, &us122l->midi_list) {
 		snd_usbmidi_disconnect(p);
 	}
 
@@ -667,7 +667,7 @@ static int snd_us122l_suspend(struct usb_interface *intf, pm_message_t message)
 	if (!us122l)
 		return 0;
 
-	list_for_each(p, &us122l->chip.midi_list)
+	list_for_each(p, &us122l->midi_list)
 		snd_usbmidi_input_stop(p);
 
 	mutex_lock(&us122l->mutex);
@@ -720,7 +720,7 @@ static int snd_us122l_resume(struct usb_interface *intf)
 	if (err)
 		goto unlock;
 
-	list_for_each(p, &us122l->chip.midi_list)
+	list_for_each(p, &us122l->midi_list)
 		snd_usbmidi_input_start(p);
 unlock:
 	mutex_unlock(&us122l->mutex);

sound/usb/usx2y/us122l.h

@@ -12,6 +12,7 @@ struct us122l {
 	unsigned		second_periods_polled;
 	struct file		*master;
 	struct file		*slave;
+	struct list_head	midi_list;
 
 	atomic_t		mmap_count;
 };

sound/usb/usx2y/usX2Yhwdep.c

@@ -171,7 +171,7 @@ static int usX2Y_create_usbmidi(struct snd_card *card)
 		&quirk_2 : &quirk_1;
 
 	snd_printdd("usX2Y_create_usbmidi \n");
-	return snd_usb_create_midi_interface(&usX2Y(card)->chip, iface, quirk);
+	return snd_usbmidi_create(card, iface, &usX2Y(card)->midi_list, quirk);
 }
 
 static int usX2Y_create_alsa_devices(struct snd_card *card)

sound/usb/usx2y/usbusx2y.c

@@ -354,7 +354,7 @@ static int usX2Y_create_card(struct usb_device *device, struct snd_card **cardp)
 	usX2Y(card)->chip.card = card;
 	init_waitqueue_head(&usX2Y(card)->prepare_wait_queue);
 	mutex_init(&usX2Y(card)->prepare_mutex);
-	INIT_LIST_HEAD(&usX2Y(card)->chip.midi_list);
+	INIT_LIST_HEAD(&usX2Y(card)->midi_list);
 	strcpy(card->driver, "USB "NAME_ALLCAPS"");
 	sprintf(card->shortname, "TASCAM "NAME_ALLCAPS"");
 	sprintf(card->longname, "%s (%x:%x if %d at %03d/%03d)",
@@ -451,7 +451,7 @@ static void usX2Y_usb_disconnect(struct usb_device *device, void* ptr)
 		usb_kill_urb(usX2Y->In04urb);
 		snd_card_disconnect(card);
 		/* release the midi resources */
-		list_for_each(p, &usX2Y->chip.midi_list) {
+		list_for_each(p, &usX2Y->midi_list) {
 			snd_usbmidi_disconnect(p);
 		}
 		if (usX2Y->us428ctls_sharedmem) 

sound/usb/usx2y/usbusx2y.h

@@ -42,6 +42,7 @@ struct usX2Ydev {
 	struct snd_usX2Y_substream	*subs[4];
 	struct snd_usX2Y_substream	* volatile  prepare_subs;
 	wait_queue_head_t	prepare_wait_queue;
+	struct list_head	midi_list;
 };
 
 

sound/usb/usx2y/usbusx2yaudio.c

@@ -740,7 +740,7 @@ static int usX2Y_format_set(struct usX2Ydev *usX2Y, snd_pcm_format_t format)
 		alternate = 1;
 		usX2Y->stride = 4;
 	}
-	list_for_each(p, &usX2Y->chip.midi_list) {
+	list_for_each(p, &usX2Y->midi_list) {
 		snd_usbmidi_input_stop(p);
 	}
 	usb_kill_urb(usX2Y->In04urb);
@@ -750,7 +750,7 @@ static int usX2Y_format_set(struct usX2Ydev *usX2Y, snd_pcm_format_t format)
 	}
 	usX2Y->In04urb->dev = usX2Y->chip.dev;
 	err = usb_submit_urb(usX2Y->In04urb, GFP_KERNEL);
-	list_for_each(p, &usX2Y->chip.midi_list) {
+	list_for_each(p, &usX2Y->midi_list) {
 		snd_usbmidi_input_start(p);
 	}
 	usX2Y->format = format;