Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 1250 insertions, 0 deletions

diff --git a/sound/usb/midi2.c b/sound/usb/midi2.c
new file mode 100644
index 000000000..1dc78f536
--- /dev/null
+++ b/sound/usb/midi2.c
@@ -0,0 +1,1250 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MIDI 2.0 support
+ */
+
+#include <linux/bitops.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/wait.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/midi.h>
+#include <linux/usb/midi-v2.h>
+
+#include <sound/core.h>
+#include <sound/control.h>
+#include <sound/ump.h>
+#include "usbaudio.h"
+#include "midi.h"
+#include "midi2.h"
+#include "helper.h"
+
+static bool midi2_enable = true;
+module_param(midi2_enable, bool, 0444);
+MODULE_PARM_DESC(midi2_enable, "Enable MIDI 2.0 support.");
+
+static bool midi2_ump_probe = true;
+module_param(midi2_ump_probe, bool, 0444);
+MODULE_PARM_DESC(midi2_ump_probe, "Probe UMP v1.1 support at first.");
+
+/* stream direction; just shorter names */
+enum {
+	STR_OUT = SNDRV_RAWMIDI_STREAM_OUTPUT,
+	STR_IN = SNDRV_RAWMIDI_STREAM_INPUT
+};
+
+#define NUM_URBS	8
+
+struct snd_usb_midi2_urb;
+struct snd_usb_midi2_endpoint;
+struct snd_usb_midi2_ump;
+struct snd_usb_midi2_interface;
+
+/* URB context */
+struct snd_usb_midi2_urb {
+	struct urb *urb;
+	struct snd_usb_midi2_endpoint *ep;
+	unsigned int index;		/* array index */
+};
+
+/* A USB MIDI input/output endpoint */
+struct snd_usb_midi2_endpoint {
+	struct usb_device *dev;
+	const struct usb_ms20_endpoint_descriptor *ms_ep; /* reference to EP descriptor */
+	struct snd_usb_midi2_endpoint *pair;	/* bidirectional pair EP */
+	struct snd_usb_midi2_ump *rmidi;	/* assigned UMP EP pair */
+	struct snd_ump_endpoint *ump;		/* assigned UMP EP */
+	int direction;			/* direction (STR_IN/OUT) */
+	unsigned int endpoint;		/* EP number */
+	unsigned int pipe;		/* URB pipe */
+	unsigned int packets;		/* packet buffer size in bytes */
+	unsigned int interval;		/* interval for INT EP */
+	wait_queue_head_t wait;		/* URB waiter */
+	spinlock_t lock;		/* URB locking */
+	struct snd_rawmidi_substream *substream; /* NULL when closed */
+	unsigned int num_urbs;		/* number of allocated URBs */
+	unsigned long urb_free;		/* bitmap for free URBs */
+	unsigned long urb_free_mask;	/* bitmask for free URBs */
+	atomic_t running;		/* running status */
+	atomic_t suspended;		/* saved running status for suspend */
+	bool disconnected;		/* shadow of umidi->disconnected */
+	struct list_head list;		/* list to umidi->ep_list */
+	struct snd_usb_midi2_urb urbs[NUM_URBS];
+};
+
+/* A UMP endpoint - one or two USB MIDI endpoints are assigned */
+struct snd_usb_midi2_ump {
+	struct usb_device *dev;
+	struct snd_usb_midi2_interface *umidi;	/* reference to MIDI iface */
+	struct snd_ump_endpoint *ump;		/* assigned UMP EP object */
+	struct snd_usb_midi2_endpoint *eps[2];	/* USB MIDI endpoints */
+	int index;				/* rawmidi device index */
+	unsigned char usb_block_id;		/* USB GTB id used for finding a pair */
+	bool ump_parsed;			/* Parsed UMP 1.1 EP/FB info*/
+	struct list_head list;		/* list to umidi->rawmidi_list */
+};
+
+/* top-level instance per USB MIDI interface */
+struct snd_usb_midi2_interface {
+	struct snd_usb_audio *chip;	/* assigned USB-audio card */
+	struct usb_interface *iface;	/* assigned USB interface */
+	struct usb_host_interface *hostif;
+	const char *blk_descs;		/* group terminal block descriptors */
+	unsigned int blk_desc_size;	/* size of GTB descriptors */
+	bool disconnected;
+	struct list_head ep_list;	/* list of endpoints */
+	struct list_head rawmidi_list;	/* list of UMP rawmidis */
+	struct list_head list;		/* list to chip->midi_v2_list */
+};
+
+/* submit URBs as much as possible; used for both input and output */
+static void do_submit_urbs_locked(struct snd_usb_midi2_endpoint *ep,
+				  int (*prepare)(struct snd_usb_midi2_endpoint *,
+						 struct urb *))
+{
+	struct snd_usb_midi2_urb *ctx;
+	int index, err = 0;
+
+	if (ep->disconnected)
+		return;
+
+	while (ep->urb_free) {
+		index = find_first_bit(&ep->urb_free, ep->num_urbs);
+		if (index >= ep->num_urbs)
+			return;
+		ctx = &ep->urbs[index];
+		err = prepare(ep, ctx->urb);
+		if (err < 0)
+			return;
+		if (!ctx->urb->transfer_buffer_length)
+			return;
+		ctx->urb->dev = ep->dev;
+		err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
+		if (err < 0) {
+			dev_dbg(&ep->dev->dev,
+				"usb_submit_urb error %d\n", err);
+			return;
+		}
+		clear_bit(index, &ep->urb_free);
+	}
+}
+
+/* prepare for output submission: copy from rawmidi buffer to urb packet */
+static int prepare_output_urb(struct snd_usb_midi2_endpoint *ep,
+			      struct urb *urb)
+{
+	int count;
+
+	count = snd_ump_transmit(ep->ump, urb->transfer_buffer,
+				 ep->packets);
+	if (count < 0) {
+		dev_dbg(&ep->dev->dev, "rawmidi transmit error %d\n", count);
+		return count;
+	}
+	cpu_to_le32_array((u32 *)urb->transfer_buffer, count >> 2);
+	urb->transfer_buffer_length = count;
+	return 0;
+}
+
+static void submit_output_urbs_locked(struct snd_usb_midi2_endpoint *ep)
+{
+	do_submit_urbs_locked(ep, prepare_output_urb);
+}
+
+/* URB completion for output; re-filling and re-submit */
+static void output_urb_complete(struct urb *urb)
+{
+	struct snd_usb_midi2_urb *ctx = urb->context;
+	struct snd_usb_midi2_endpoint *ep = ctx->ep;
+
+	guard(spinlock_irqsave)(&ep->lock);
+	set_bit(ctx->index, &ep->urb_free);
+	if (urb->status >= 0 && atomic_read(&ep->running))
+		submit_output_urbs_locked(ep);
+	if (ep->urb_free == ep->urb_free_mask)
+		wake_up(&ep->wait);
+}
+
+/* prepare for input submission: just set the buffer length */
+static int prepare_input_urb(struct snd_usb_midi2_endpoint *ep,
+			     struct urb *urb)
+{
+	urb->transfer_buffer_length = ep->packets;
+	return 0;
+}
+
+static void submit_input_urbs_locked(struct snd_usb_midi2_endpoint *ep)
+{
+	do_submit_urbs_locked(ep, prepare_input_urb);
+}
+
+/* URB completion for input; copy into rawmidi buffer and resubmit */
+static void input_urb_complete(struct urb *urb)
+{
+	struct snd_usb_midi2_urb *ctx = urb->context;
+	struct snd_usb_midi2_endpoint *ep = ctx->ep;
+	int len;
+
+	guard(spinlock_irqsave)(&ep->lock);
+	if (ep->disconnected || urb->status < 0)
+		goto dequeue;
+	len = urb->actual_length;
+	len &= ~3; /* align UMP */
+	if (len > ep->packets)
+		len = ep->packets;
+	if (len > 0) {
+		le32_to_cpu_array((u32 *)urb->transfer_buffer, len >> 2);
+		snd_ump_receive(ep->ump, (u32 *)urb->transfer_buffer, len);
+	}
+ dequeue:
+	set_bit(ctx->index, &ep->urb_free);
+	submit_input_urbs_locked(ep);
+	if (ep->urb_free == ep->urb_free_mask)
+		wake_up(&ep->wait);
+}
+
+/* URB submission helper; for both direction */
+static void submit_io_urbs(struct snd_usb_midi2_endpoint *ep)
+{
+	if (!ep)
+		return;
+	guard(spinlock_irqsave)(&ep->lock);
+	if (ep->direction == STR_IN)
+		submit_input_urbs_locked(ep);
+	else
+		submit_output_urbs_locked(ep);
+}
+
+/* kill URBs for close, suspend and disconnect */
+static void kill_midi_urbs(struct snd_usb_midi2_endpoint *ep, bool suspending)
+{
+	int i;
+
+	if (!ep)
+		return;
+	if (suspending)
+		atomic_set(&ep->suspended, atomic_read(&ep->running));
+	atomic_set(&ep->running, 0);
+	for (i = 0; i < ep->num_urbs; i++) {
+		if (!ep->urbs[i].urb)
+			break;
+		usb_kill_urb(ep->urbs[i].urb);
+	}
+}
+
+/* wait until all URBs get freed */
+static void drain_urb_queue(struct snd_usb_midi2_endpoint *ep)
+{
+	if (!ep)
+		return;
+	guard(spinlock_irq)(&ep->lock);
+	atomic_set(&ep->running, 0);
+	wait_event_lock_irq_timeout(ep->wait,
+				    ep->disconnected ||
+				    ep->urb_free == ep->urb_free_mask,
+				    ep->lock, msecs_to_jiffies(500));
+}
+
+/* release URBs for an EP */
+static void free_midi_urbs(struct snd_usb_midi2_endpoint *ep)
+{
+	struct snd_usb_midi2_urb *ctx;
+	int i;
+
+	if (!ep)
+		return;
+	for (i = 0; i < NUM_URBS; ++i) {
+		ctx = &ep->urbs[i];
+		if (!ctx->urb)
+			break;
+		usb_free_coherent(ep->dev, ep->packets,
+				  ctx->urb->transfer_buffer,
+				  ctx->urb->transfer_dma);
+		usb_free_urb(ctx->urb);
+		ctx->urb = NULL;
+	}
+	ep->num_urbs = 0;
+}
+
+/* allocate URBs for an EP */
+/* the callers should handle allocation errors via free_midi_urbs() */
+static int alloc_midi_urbs(struct snd_usb_midi2_endpoint *ep)
+{
+	struct snd_usb_midi2_urb *ctx;
+	void (*comp)(struct urb *urb);
+	void *buffer;
+	int i, err;
+	int endpoint, len;
+
+	endpoint = ep->endpoint;
+	len = ep->packets;
+	if (ep->direction == STR_IN)
+		comp = input_urb_complete;
+	else
+		comp = output_urb_complete;
+
+	ep->num_urbs = 0;
+	ep->urb_free = ep->urb_free_mask = 0;
+	for (i = 0; i < NUM_URBS; i++) {
+		ctx = &ep->urbs[i];
+		ctx->index = i;
+		ctx->urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!ctx->urb) {
+			dev_err(&ep->dev->dev, "URB alloc failed\n");
+			return -ENOMEM;
+		}
+		ctx->ep = ep;
+		buffer = usb_alloc_coherent(ep->dev, len, GFP_KERNEL,
+					    &ctx->urb->transfer_dma);
+		if (!buffer) {
+			dev_err(&ep->dev->dev,
+				"URB buffer alloc failed (size %d)\n", len);
+			return -ENOMEM;
+		}
+		if (ep->interval)
+			usb_fill_int_urb(ctx->urb, ep->dev, ep->pipe,
+					 buffer, len, comp, ctx, ep->interval);
+		else
+			usb_fill_bulk_urb(ctx->urb, ep->dev, ep->pipe,
+					  buffer, len, comp, ctx);
+		err = usb_urb_ep_type_check(ctx->urb);
+		if (err < 0) {
+			dev_err(&ep->dev->dev, "invalid MIDI EP %x\n",
+				endpoint);
+			return err;
+		}
+		ctx->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
+		ep->num_urbs++;
+	}
+	ep->urb_free = ep->urb_free_mask = GENMASK(ep->num_urbs - 1, 0);
+	return 0;
+}
+
+static struct snd_usb_midi2_endpoint *
+ump_to_endpoint(struct snd_ump_endpoint *ump, int dir)
+{
+	struct snd_usb_midi2_ump *rmidi = ump->private_data;
+
+	return rmidi ? rmidi->eps[dir] : NULL;
+}
+
+/* ump open callback */
+static int snd_usb_midi_v2_open(struct snd_ump_endpoint *ump, int dir)
+{
+	struct snd_usb_midi2_endpoint *ep = ump_to_endpoint(ump, dir);
+	int err = 0;
+
+	if (!ep || !ep->endpoint)
+		return -ENODEV;
+	if (ep->disconnected)
+		return -EIO;
+	if (ep->direction == STR_OUT) {
+		err = alloc_midi_urbs(ep);
+		if (err) {
+			free_midi_urbs(ep);
+			return err;
+		}
+	}
+	return 0;
+}
+
+/* ump close callback */
+static void snd_usb_midi_v2_close(struct snd_ump_endpoint *ump, int dir)
+{
+	struct snd_usb_midi2_endpoint *ep = ump_to_endpoint(ump, dir);
+
+	if (ep->direction == STR_OUT) {
+		kill_midi_urbs(ep, false);
+		drain_urb_queue(ep);
+		free_midi_urbs(ep);
+	}
+}
+
+/* ump trigger callback */
+static void snd_usb_midi_v2_trigger(struct snd_ump_endpoint *ump, int dir,
+				    int up)
+{
+	struct snd_usb_midi2_endpoint *ep = ump_to_endpoint(ump, dir);
+
+	atomic_set(&ep->running, up);
+	if (up && ep->direction == STR_OUT && !ep->disconnected)
+		submit_io_urbs(ep);
+}
+
+/* ump drain callback */
+static void snd_usb_midi_v2_drain(struct snd_ump_endpoint *ump, int dir)
+{
+	struct snd_usb_midi2_endpoint *ep = ump_to_endpoint(ump, dir);
+
+	drain_urb_queue(ep);
+}
+
+/* allocate and start all input streams */
+static int start_input_streams(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_endpoint *ep;
+	int err;
+
+	list_for_each_entry(ep, &umidi->ep_list, list) {
+		if (ep->direction == STR_IN) {
+			err = alloc_midi_urbs(ep);
+			if (err < 0)
+				goto error;
+		}
+	}
+
+	list_for_each_entry(ep, &umidi->ep_list, list) {
+		if (ep->direction == STR_IN)
+			submit_io_urbs(ep);
+	}
+
+	return 0;
+
+ error:
+	list_for_each_entry(ep, &umidi->ep_list, list) {
+		if (ep->direction == STR_IN)
+			free_midi_urbs(ep);
+	}
+
+	return err;
+}
+
+static const struct snd_ump_ops snd_usb_midi_v2_ump_ops = {
+	.open = snd_usb_midi_v2_open,
+	.close = snd_usb_midi_v2_close,
+	.trigger = snd_usb_midi_v2_trigger,
+	.drain = snd_usb_midi_v2_drain,
+};
+
+/* create a USB MIDI 2.0 endpoint object */
+static int create_midi2_endpoint(struct snd_usb_midi2_interface *umidi,
+				 struct usb_host_endpoint *hostep,
+				 const struct usb_ms20_endpoint_descriptor *ms_ep)
+{
+	struct snd_usb_midi2_endpoint *ep;
+	int endpoint, dir;
+
+	usb_audio_dbg(umidi->chip, "Creating an EP 0x%02x, #GTB=%d\n",
+		      hostep->desc.bEndpointAddress,
+		      ms_ep->bNumGrpTrmBlock);
+
+	ep = kzalloc_obj(*ep);
+	if (!ep)
+		return -ENOMEM;
+
+	spin_lock_init(&ep->lock);
+	init_waitqueue_head(&ep->wait);
+	ep->dev = umidi->chip->dev;
+	endpoint = hostep->desc.bEndpointAddress;
+	dir = (endpoint & USB_DIR_IN) ? STR_IN : STR_OUT;
+
+	ep->endpoint = endpoint;
+	ep->direction = dir;
+	ep->ms_ep = ms_ep;
+	if (usb_endpoint_xfer_int(&hostep->desc))
+		ep->interval = hostep->desc.bInterval;
+	else
+		ep->interval = 0;
+	if (dir == STR_IN) {
+		if (ep->interval)
+			ep->pipe = usb_rcvintpipe(ep->dev, endpoint);
+		else
+			ep->pipe = usb_rcvbulkpipe(ep->dev, endpoint);
+	} else {
+		if (ep->interval)
+			ep->pipe = usb_sndintpipe(ep->dev, endpoint);
+		else
+			ep->pipe = usb_sndbulkpipe(ep->dev, endpoint);
+	}
+	ep->packets = usb_maxpacket(ep->dev, ep->pipe);
+	list_add_tail(&ep->list, &umidi->ep_list);
+
+	return 0;
+}
+
+/* destructor for endpoint; from snd_usb_midi_v2_free() */
+static void free_midi2_endpoint(struct snd_usb_midi2_endpoint *ep)
+{
+	list_del(&ep->list);
+	if (!ep->disconnected) {
+		ep->disconnected = 1;
+		kill_midi_urbs(ep, false);
+		drain_urb_queue(ep);
+	}
+	free_midi_urbs(ep);
+	kfree(ep);
+}
+
+/* call all endpoint destructors */
+static void free_all_midi2_endpoints(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_endpoint *ep;
+
+	while (!list_empty(&umidi->ep_list)) {
+		ep = list_first_entry(&umidi->ep_list,
+				      struct snd_usb_midi2_endpoint, list);
+		free_midi2_endpoint(ep);
+	}
+}
+
+/* find a MIDI STREAMING descriptor with a given subtype */
+static void *find_usb_ms_endpoint_descriptor(struct usb_host_endpoint *hostep,
+					     unsigned char subtype)
+{
+	unsigned char *extra = hostep->extra;
+	int extralen = hostep->extralen;
+
+	while (extralen > 3) {
+		struct usb_ms_endpoint_descriptor *ms_ep =
+			(struct usb_ms_endpoint_descriptor *)extra;
+		int length = ms_ep->bLength;
+
+		if (!length || length > extralen)
+			break;
+
+		if (length > 3 &&
+		    ms_ep->bDescriptorType == USB_DT_CS_ENDPOINT &&
+		    ms_ep->bDescriptorSubtype == subtype)
+			return ms_ep;
+		extralen -= length;
+		extra += length;
+	}
+	return NULL;
+}
+
+/* get the full group terminal block descriptors and return the size */
+static int get_group_terminal_block_descs(struct snd_usb_midi2_interface *umidi)
+{
+	struct usb_host_interface *hostif = umidi->hostif;
+	struct usb_device *dev = umidi->chip->dev;
+	struct usb_ms20_gr_trm_block_header_descriptor header = { 0 };
+	unsigned char *data;
+	int err, size;
+
+	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+			      USB_REQ_GET_DESCRIPTOR,
+			      USB_RECIP_INTERFACE | USB_TYPE_STANDARD | USB_DIR_IN,
+			      USB_DT_CS_GR_TRM_BLOCK << 8 | hostif->desc.bAlternateSetting,
+			      hostif->desc.bInterfaceNumber,
+			      &header, sizeof(header));
+	if (err < 0)
+		return err;
+	size = __le16_to_cpu(header.wTotalLength);
+	if (!size) {
+		dev_err(&dev->dev, "Failed to get GTB descriptors for %d:%d\n",
+			hostif->desc.bInterfaceNumber, hostif->desc.bAlternateSetting);
+		return -EINVAL;
+	}
+
+	data = kzalloc(size, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+			      USB_REQ_GET_DESCRIPTOR,
+			      USB_RECIP_INTERFACE | USB_TYPE_STANDARD | USB_DIR_IN,
+			      USB_DT_CS_GR_TRM_BLOCK << 8 | hostif->desc.bAlternateSetting,
+			      hostif->desc.bInterfaceNumber, data, size);
+	if (err < 0) {
+		kfree(data);
+		return err;
+	}
+
+	umidi->blk_descs = data;
+	umidi->blk_desc_size = size;
+	return 0;
+}
+
+/* find the corresponding group terminal block descriptor */
+static const struct usb_ms20_gr_trm_block_descriptor *
+find_group_terminal_block(struct snd_usb_midi2_interface *umidi, int id)
+{
+	const unsigned char *data = umidi->blk_descs;
+	int size = umidi->blk_desc_size;
+	const struct usb_ms20_gr_trm_block_descriptor *desc;
+
+	size -= sizeof(struct usb_ms20_gr_trm_block_header_descriptor);
+	data += sizeof(struct usb_ms20_gr_trm_block_header_descriptor);
+	while (size > 0 && *data && *data <= size) {
+		desc = (const struct usb_ms20_gr_trm_block_descriptor *)data;
+		if (desc->bLength >= sizeof(*desc) &&
+		    desc->bDescriptorType == USB_DT_CS_GR_TRM_BLOCK &&
+		    desc->bDescriptorSubtype == USB_MS_GR_TRM_BLOCK &&
+		    desc->bGrpTrmBlkID == id)
+			return desc;
+		size -= *data;
+		data += *data;
+	}
+
+	return NULL;
+}
+
+/* fill up the information from GTB */
+static int parse_group_terminal_block(struct snd_usb_midi2_ump *rmidi,
+				      const struct usb_ms20_gr_trm_block_descriptor *desc)
+{
+	struct snd_ump_endpoint *ump = rmidi->ump;
+	unsigned int protocol, protocol_caps;
+
+	/* set default protocol */
+	switch (desc->bMIDIProtocol) {
+	case USB_MS_MIDI_PROTO_1_0_64:
+	case USB_MS_MIDI_PROTO_1_0_64_JRTS:
+	case USB_MS_MIDI_PROTO_1_0_128:
+	case USB_MS_MIDI_PROTO_1_0_128_JRTS:
+		protocol = SNDRV_UMP_EP_INFO_PROTO_MIDI1;
+		break;
+	case USB_MS_MIDI_PROTO_2_0:
+	case USB_MS_MIDI_PROTO_2_0_JRTS:
+		protocol = SNDRV_UMP_EP_INFO_PROTO_MIDI2;
+		break;
+	default:
+		return 0;
+	}
+
+	if (!ump->info.protocol)
+		ump->info.protocol = protocol;
+
+	protocol_caps = protocol;
+	switch (desc->bMIDIProtocol) {
+	case USB_MS_MIDI_PROTO_1_0_64_JRTS:
+	case USB_MS_MIDI_PROTO_1_0_128_JRTS:
+	case USB_MS_MIDI_PROTO_2_0_JRTS:
+		protocol_caps |= SNDRV_UMP_EP_INFO_PROTO_JRTS_TX |
+			SNDRV_UMP_EP_INFO_PROTO_JRTS_RX;
+		break;
+	}
+
+	ump->info.protocol_caps |= protocol_caps;
+	return 0;
+}
+
+/* allocate and parse for each assigned group terminal block */
+static int parse_group_terminal_blocks(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_ump *rmidi;
+	const struct usb_ms20_gr_trm_block_descriptor *desc;
+	int err;
+
+	err = get_group_terminal_block_descs(umidi);
+	if (err < 0)
+		return err;
+	if (!umidi->blk_descs)
+		return 0;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		desc = find_group_terminal_block(umidi, rmidi->usb_block_id);
+		if (!desc)
+			continue;
+		err = parse_group_terminal_block(rmidi, desc);
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+
+/* parse endpoints included in the given interface and create objects */
+static int parse_midi_2_0_endpoints(struct snd_usb_midi2_interface *umidi)
+{
+	struct usb_host_interface *hostif = umidi->hostif;
+	struct usb_host_endpoint *hostep;
+	struct usb_ms20_endpoint_descriptor *ms_ep;
+	int i, err;
+
+	for (i = 0; i < hostif->desc.bNumEndpoints; i++) {
+		hostep = &hostif->endpoint[i];
+		if (!usb_endpoint_xfer_bulk(&hostep->desc) &&
+		    !usb_endpoint_xfer_int(&hostep->desc))
+			continue;
+		ms_ep = find_usb_ms_endpoint_descriptor(hostep, USB_MS_GENERAL_2_0);
+		if (!ms_ep)
+			continue;
+		if (ms_ep->bLength <= sizeof(*ms_ep))
+			continue;
+		if (!ms_ep->bNumGrpTrmBlock)
+			continue;
+		if (ms_ep->bLength < sizeof(*ms_ep) + ms_ep->bNumGrpTrmBlock)
+			continue;
+		err = create_midi2_endpoint(umidi, hostep, ms_ep);
+		if (err < 0)
+			return err;
+	}
+	return 0;
+}
+
+static void free_ump_private_data(struct snd_ump_endpoint *ump)
+{
+	struct snd_usb_midi2_ump *rmidi = ump->private_data;
+
+	if (rmidi)
+		rmidi->ump = NULL;
+}
+
+static void free_all_midi2_umps(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_ump *rmidi;
+
+	while (!list_empty(&umidi->rawmidi_list)) {
+		rmidi = list_first_entry(&umidi->rawmidi_list,
+					 struct snd_usb_midi2_ump, list);
+		list_del(&rmidi->list);
+		if (rmidi->ump)
+			rmidi->ump->private_data = NULL;
+		kfree(rmidi);
+	}
+}
+
+static int create_midi2_ump(struct snd_usb_midi2_interface *umidi,
+			    struct snd_usb_midi2_endpoint *ep_in,
+			    struct snd_usb_midi2_endpoint *ep_out,
+			    int blk_id)
+{
+	struct snd_usb_midi2_ump *rmidi;
+	struct snd_ump_endpoint *ump;
+	int input, output;
+	char idstr[16];
+	int err;
+
+	rmidi = kzalloc_obj(*rmidi);
+	if (!rmidi)
+		return -ENOMEM;
+	INIT_LIST_HEAD(&rmidi->list);
+	rmidi->dev = umidi->chip->dev;
+	rmidi->umidi = umidi;
+	rmidi->usb_block_id = blk_id;
+
+	rmidi->index = umidi->chip->num_rawmidis;
+	snprintf(idstr, sizeof(idstr), "UMP %d", rmidi->index);
+	input = ep_in ? 1 : 0;
+	output = ep_out ? 1 : 0;
+	err = snd_ump_endpoint_new(umidi->chip->card, idstr, rmidi->index,
+				   output, input, &ump);
+	if (err < 0) {
+		usb_audio_dbg(umidi->chip, "Failed to create a UMP object\n");
+		kfree(rmidi);
+		return err;
+	}
+
+	rmidi->ump = ump;
+	umidi->chip->num_rawmidis++;
+
+	ump->private_data = rmidi;
+	ump->ops = &snd_usb_midi_v2_ump_ops;
+	ump->private_free = free_ump_private_data;
+
+	rmidi->eps[STR_IN] = ep_in;
+	rmidi->eps[STR_OUT] = ep_out;
+	if (ep_in) {
+		ep_in->pair = ep_out;
+		ep_in->rmidi = rmidi;
+		ep_in->ump = ump;
+	}
+	if (ep_out) {
+		ep_out->pair = ep_in;
+		ep_out->rmidi = rmidi;
+		ep_out->ump = ump;
+	}
+
+	list_add_tail(&rmidi->list, &umidi->rawmidi_list);
+	return 0;
+}
+
+/* find the UMP EP with the given USB block id */
+static struct snd_usb_midi2_ump *
+find_midi2_ump(struct snd_usb_midi2_interface *umidi, int blk_id)
+{
+	struct snd_usb_midi2_ump *rmidi;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		if (rmidi->usb_block_id == blk_id)
+			return rmidi;
+	}
+	return NULL;
+}
+
+/* look for the matching output endpoint and create UMP object if found */
+static int find_matching_ep_partner(struct snd_usb_midi2_interface *umidi,
+				    struct snd_usb_midi2_endpoint *ep,
+				    int blk_id)
+{
+	struct snd_usb_midi2_endpoint *pair_ep;
+	int blk;
+
+	usb_audio_dbg(umidi->chip, "Looking for a pair for EP-in 0x%02x\n",
+		      ep->endpoint);
+	list_for_each_entry(pair_ep, &umidi->ep_list, list) {
+		if (pair_ep->direction != STR_OUT)
+			continue;
+		if (pair_ep->pair)
+			continue; /* already paired */
+		for (blk = 0; blk < pair_ep->ms_ep->bNumGrpTrmBlock; blk++) {
+			if (pair_ep->ms_ep->baAssoGrpTrmBlkID[blk] == blk_id) {
+				usb_audio_dbg(umidi->chip,
+					      "Found a match with EP-out 0x%02x blk %d\n",
+					      pair_ep->endpoint, blk);
+				return create_midi2_ump(umidi, ep, pair_ep, blk_id);
+			}
+		}
+	}
+	return 0;
+}
+
+/* Call UMP helper to parse UMP endpoints;
+ * this needs to be called after starting the input streams for bi-directional
+ * communications
+ */
+static int parse_ump_endpoints(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_ump *rmidi;
+	int err;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		if (!rmidi->ump ||
+		    !(rmidi->ump->core.info_flags & SNDRV_RAWMIDI_INFO_DUPLEX))
+			continue;
+		err = snd_ump_parse_endpoint(rmidi->ump);
+		if (!err) {
+			rmidi->ump_parsed = true;
+		} else {
+			if (err == -ENOMEM)
+				return err;
+			/* fall back to GTB later */
+		}
+	}
+	return 0;
+}
+
+/* create a UMP block from a GTB entry */
+static int create_gtb_block(struct snd_usb_midi2_ump *rmidi, int dir, int blk)
+{
+	struct snd_usb_midi2_interface *umidi = rmidi->umidi;
+	const struct usb_ms20_gr_trm_block_descriptor *desc;
+	struct snd_ump_block *fb;
+	int type, err;
+
+	desc = find_group_terminal_block(umidi, blk);
+	if (!desc)
+		return 0;
+
+	usb_audio_dbg(umidi->chip,
+		      "GTB %d: type=%d, group=%d/%d, protocol=%d, in bw=%d, out bw=%d\n",
+		      blk, desc->bGrpTrmBlkType, desc->nGroupTrm,
+		      desc->nNumGroupTrm, desc->bMIDIProtocol,
+		      __le16_to_cpu(desc->wMaxInputBandwidth),
+		      __le16_to_cpu(desc->wMaxOutputBandwidth));
+
+	/* assign the direction */
+	switch (desc->bGrpTrmBlkType) {
+	case USB_MS_GR_TRM_BLOCK_TYPE_BIDIRECTIONAL:
+		type = SNDRV_UMP_DIR_BIDIRECTION;
+		break;
+	case USB_MS_GR_TRM_BLOCK_TYPE_INPUT_ONLY:
+		type = SNDRV_UMP_DIR_INPUT;
+		break;
+	case USB_MS_GR_TRM_BLOCK_TYPE_OUTPUT_ONLY:
+		type = SNDRV_UMP_DIR_OUTPUT;
+		break;
+	default:
+		usb_audio_dbg(umidi->chip, "Unsupported GTB type %d\n",
+			      desc->bGrpTrmBlkType);
+		return 0; /* unsupported */
+	}
+
+	/* guess work: set blk-1 as the (0-based) block ID */
+	err = snd_ump_block_new(rmidi->ump, blk - 1, type,
+				desc->nGroupTrm, desc->nNumGroupTrm,
+				&fb);
+	if (err == -EBUSY)
+		return 0; /* already present */
+	else if (err)
+		return err;
+
+	if (desc->iBlockItem)
+		usb_string(rmidi->dev, desc->iBlockItem,
+			   fb->info.name, sizeof(fb->info.name));
+
+	if (__le16_to_cpu(desc->wMaxInputBandwidth) == 1 ||
+	    __le16_to_cpu(desc->wMaxOutputBandwidth) == 1)
+		fb->info.flags |= SNDRV_UMP_BLOCK_IS_MIDI1 |
+			SNDRV_UMP_BLOCK_IS_LOWSPEED;
+
+	/* if MIDI 2.0 protocol is supported and yet the GTB shows MIDI 1.0,
+	 * treat it as a MIDI 1.0-specific block
+	 */
+	if (rmidi->ump->info.protocol_caps & SNDRV_UMP_EP_INFO_PROTO_MIDI2) {
+		switch (desc->bMIDIProtocol) {
+		case USB_MS_MIDI_PROTO_1_0_64:
+		case USB_MS_MIDI_PROTO_1_0_64_JRTS:
+		case USB_MS_MIDI_PROTO_1_0_128:
+		case USB_MS_MIDI_PROTO_1_0_128_JRTS:
+			fb->info.flags |= SNDRV_UMP_BLOCK_IS_MIDI1;
+			break;
+		}
+	}
+
+	snd_ump_update_group_attrs(rmidi->ump);
+
+	usb_audio_dbg(umidi->chip,
+		      "Created a UMP block %d from GTB, name=%s, flags=0x%x\n",
+		      blk, fb->info.name, fb->info.flags);
+	return 0;
+}
+
+/* Create UMP blocks for each UMP EP */
+static int create_blocks_from_gtb(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_ump *rmidi;
+	int i, blk, err, dir;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		if (!rmidi->ump)
+			continue;
+		/* Blocks have been already created? */
+		if (rmidi->ump_parsed || rmidi->ump->info.num_blocks)
+			continue;
+		/* GTB is static-only */
+		rmidi->ump->info.flags |= SNDRV_UMP_EP_INFO_STATIC_BLOCKS;
+		/* loop over GTBs */
+		for (dir = 0; dir < 2; dir++) {
+			if (!rmidi->eps[dir])
+				continue;
+			for (i = 0; i < rmidi->eps[dir]->ms_ep->bNumGrpTrmBlock; i++) {
+				blk = rmidi->eps[dir]->ms_ep->baAssoGrpTrmBlkID[i];
+				err = create_gtb_block(rmidi, dir, blk);
+				if (err < 0)
+					return err;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/* attach legacy rawmidis */
+static int attach_legacy_rawmidi(struct snd_usb_midi2_interface *umidi)
+{
+#if IS_ENABLED(CONFIG_SND_UMP_LEGACY_RAWMIDI)
+	struct snd_usb_midi2_ump *rmidi;
+	int err;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		err = snd_ump_attach_legacy_rawmidi(rmidi->ump,
+						    "Legacy MIDI",
+						    umidi->chip->num_rawmidis);
+		if (err < 0)
+			return err;
+		umidi->chip->num_rawmidis++;
+	}
+#endif
+	return 0;
+}
+
+static void snd_usb_midi_v2_free(struct snd_usb_midi2_interface *umidi)
+{
+	free_all_midi2_endpoints(umidi);
+	free_all_midi2_umps(umidi);
+	list_del(&umidi->list);
+	kfree(umidi->blk_descs);
+	kfree(umidi);
+}
+
+/* parse the interface for MIDI 2.0 */
+static int parse_midi_2_0(struct snd_usb_midi2_interface *umidi)
+{
+	struct snd_usb_midi2_endpoint *ep;
+	int blk, id, err;
+
+	/* First, create an object for each USB MIDI Endpoint */
+	err = parse_midi_2_0_endpoints(umidi);
+	if (err < 0)
+		return err;
+	if (list_empty(&umidi->ep_list)) {
+		usb_audio_warn(umidi->chip, "No MIDI endpoints found\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Next, look for EP I/O pairs that are found in group terminal blocks
+	 * A UMP object is created for each EP I/O pair as bidirecitonal
+	 * UMP EP
+	 */
+	list_for_each_entry(ep, &umidi->ep_list, list) {
+		/* only input in this loop; output is matched in find_midi_ump() */
+		if (ep->direction != STR_IN)
+			continue;
+		for (blk = 0; blk < ep->ms_ep->bNumGrpTrmBlock; blk++) {
+			id = ep->ms_ep->baAssoGrpTrmBlkID[blk];
+			err = find_matching_ep_partner(umidi, ep, id);
+			if (err < 0)
+				return err;
+		}
+	}
+
+	/*
+	 * For the remaining EPs, treat as singles, create a UMP object with
+	 * unidirectional EP
+	 */
+	list_for_each_entry(ep, &umidi->ep_list, list) {
+		if (ep->rmidi)
+			continue; /* already paired */
+		for (blk = 0; blk < ep->ms_ep->bNumGrpTrmBlock; blk++) {
+			id = ep->ms_ep->baAssoGrpTrmBlkID[blk];
+			if (find_midi2_ump(umidi, id))
+				continue;
+			usb_audio_dbg(umidi->chip,
+				      "Creating a unidirection UMP for EP=0x%02x, blk=%d\n",
+				      ep->endpoint, id);
+			if (ep->direction == STR_IN)
+				err = create_midi2_ump(umidi, ep, NULL, id);
+			else
+				err = create_midi2_ump(umidi, NULL, ep, id);
+			if (err < 0)
+				return err;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+/* is the given interface for MIDI 2.0? */
+static bool is_midi2_altset(struct usb_host_interface *hostif)
+{
+	struct usb_ms_header_descriptor *ms_header =
+		(struct usb_ms_header_descriptor *)hostif->extra;
+
+	if (hostif->extralen < 7 ||
+	    ms_header->bLength < 7 ||
+	    ms_header->bDescriptorType != USB_DT_CS_INTERFACE ||
+	    ms_header->bDescriptorSubtype != UAC_HEADER)
+		return false;
+
+	return le16_to_cpu(ms_header->bcdMSC) == USB_MS_REV_MIDI_2_0;
+}
+
+/* change the altsetting */
+static int set_altset(struct snd_usb_midi2_interface *umidi)
+{
+	usb_audio_dbg(umidi->chip, "Setting host iface %d:%d\n",
+		      umidi->hostif->desc.bInterfaceNumber,
+		      umidi->hostif->desc.bAlternateSetting);
+	return usb_set_interface(umidi->chip->dev,
+				 umidi->hostif->desc.bInterfaceNumber,
+				 umidi->hostif->desc.bAlternateSetting);
+}
+
+/* fill UMP Endpoint name string from USB descriptor */
+static void fill_ump_ep_name(struct snd_ump_endpoint *ump,
+			     struct usb_device *dev, int id)
+{
+	int len;
+
+	usb_string(dev, id, ump->info.name, sizeof(ump->info.name));
+
+	/* trim superfluous "MIDI" suffix */
+	len = strlen(ump->info.name);
+	if (len > 5 && !strcmp(ump->info.name + len - 5, " MIDI"))
+		ump->info.name[len - 5] = 0;
+}
+
+/* fill the fallback name string for each rawmidi instance */
+static void set_fallback_rawmidi_names(struct snd_usb_midi2_interface *umidi)
+{
+	struct usb_device *dev = umidi->chip->dev;
+	struct snd_usb_midi2_ump *rmidi;
+	struct snd_ump_endpoint *ump;
+
+	list_for_each_entry(rmidi, &umidi->rawmidi_list, list) {
+		ump = rmidi->ump;
+		/* fill UMP EP name from USB descriptors */
+		if (!*ump->info.name && umidi->hostif->desc.iInterface)
+			fill_ump_ep_name(ump, dev, umidi->hostif->desc.iInterface);
+		else if (!*ump->info.name && dev->descriptor.iProduct)
+			fill_ump_ep_name(ump, dev, dev->descriptor.iProduct);
+		/* fill fallback name */
+		if (!*ump->info.name)
+			scnprintf(ump->info.name, sizeof(ump->info.name),
+				  "USB MIDI %d", rmidi->index);
+		/* copy as rawmidi name if not set */
+		if (!*ump->core.name)
+			strscpy(ump->core.name, ump->info.name,
+				sizeof(ump->core.name));
+		/* use serial number string as unique UMP product id */
+		if (!*ump->info.product_id && dev->serial && *dev->serial)
+			strscpy(ump->info.product_id, dev->serial);
+	}
+}
+
+/* create MIDI interface; fallback to MIDI 1.0 if needed */
+int snd_usb_midi_v2_create(struct snd_usb_audio *chip,
+			   struct usb_interface *iface,
+			   const struct snd_usb_audio_quirk *quirk,
+			   unsigned int usb_id)
+{
+	struct snd_usb_midi2_interface *umidi;
+	struct usb_host_interface *hostif;
+	int err;
+
+	usb_audio_dbg(chip, "Parsing interface %d...\n",
+		      iface->altsetting[0].desc.bInterfaceNumber);
+
+	/* fallback to MIDI 1.0? */
+	if (!midi2_enable) {
+		usb_audio_info(chip, "Falling back to MIDI 1.0 by module option\n");
+		goto fallback_to_midi1;
+	}
+	if ((quirk && quirk->type != QUIRK_MIDI_STANDARD_INTERFACE) ||
+	    iface->num_altsetting < 2) {
+		usb_audio_info(chip, "Quirk or no altset; falling back to MIDI 1.0\n");
+		goto fallback_to_midi1;
+	}
+	hostif = &iface->altsetting[1];
+	if (!is_midi2_altset(hostif)) {
+		usb_audio_info(chip, "No MIDI 2.0 at altset 1, falling back to MIDI 1.0\n");
+		goto fallback_to_midi1;
+	}
+	if (!hostif->desc.bNumEndpoints) {
+		usb_audio_info(chip, "No endpoint at altset 1, falling back to MIDI 1.0\n");
+		goto fallback_to_midi1;
+	}
+
+	usb_audio_dbg(chip, "Creating a MIDI 2.0 instance for %d:%d\n",
+		      hostif->desc.bInterfaceNumber,
+		      hostif->desc.bAlternateSetting);
+
+	umidi = kzalloc_obj(*umidi);
+	if (!umidi)
+		return -ENOMEM;
+	umidi->chip = chip;
+	umidi->iface = iface;
+	umidi->hostif = hostif;
+	INIT_LIST_HEAD(&umidi->rawmidi_list);
+	INIT_LIST_HEAD(&umidi->ep_list);
+
+	list_add_tail(&umidi->list, &chip->midi_v2_list);
+
+	err = set_altset(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to set altset\n");
+		goto error;
+	}
+
+	/* assume only altset 1 corresponding to MIDI 2.0 interface */
+	err = parse_midi_2_0(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to parse MIDI 2.0 interface\n");
+		goto error;
+	}
+
+	/* parse USB group terminal blocks */
+	err = parse_group_terminal_blocks(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to parse GTB\n");
+		goto error;
+	}
+
+	err = start_input_streams(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to start input streams\n");
+		goto error;
+	}
+
+	if (midi2_ump_probe) {
+		err = parse_ump_endpoints(umidi);
+		if (err < 0) {
+			usb_audio_err(chip, "Failed to parse UMP endpoint\n");
+			goto error;
+		}
+	}
+
+	err = create_blocks_from_gtb(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to create GTB blocks\n");
+		goto error;
+	}
+
+	set_fallback_rawmidi_names(umidi);
+
+	err = attach_legacy_rawmidi(umidi);
+	if (err < 0) {
+		usb_audio_err(chip, "Failed to create legacy rawmidi\n");
+		goto error;
+	}
+
+	return 0;
+
+ error:
+	snd_usb_midi_v2_free(umidi);
+	return err;
+
+ fallback_to_midi1:
+	return __snd_usbmidi_create(chip->card, iface, &chip->midi_list,
+				    quirk, usb_id, &chip->num_rawmidis);
+}
+
+static void suspend_midi2_endpoint(struct snd_usb_midi2_endpoint *ep)
+{
+	kill_midi_urbs(ep, true);
+	drain_urb_queue(ep);
+}
+
+void snd_usb_midi_v2_suspend_all(struct snd_usb_audio *chip)
+{
+	struct snd_usb_midi2_interface *umidi;
+	struct snd_usb_midi2_endpoint *ep;
+
+	list_for_each_entry(umidi, &chip->midi_v2_list, list) {
+		list_for_each_entry(ep, &umidi->ep_list, list)
+			suspend_midi2_endpoint(ep);
+	}
+}
+
+static void resume_midi2_endpoint(struct snd_usb_midi2_endpoint *ep)
+{
+	atomic_set(&ep->running, atomic_read(&ep->suspended));
+	atomic_set(&ep->suspended, 0);
+
+	if (ep->direction == STR_IN || atomic_read(&ep->running))
+		submit_io_urbs(ep);
+}
+
+void snd_usb_midi_v2_resume_all(struct snd_usb_audio *chip)
+{
+	struct snd_usb_midi2_interface *umidi;
+	struct snd_usb_midi2_endpoint *ep;
+
+	list_for_each_entry(umidi, &chip->midi_v2_list, list) {
+		set_altset(umidi);
+		list_for_each_entry(ep, &umidi->ep_list, list)
+			resume_midi2_endpoint(ep);
+	}
+}
+
+void snd_usb_midi_v2_disconnect_all(struct snd_usb_audio *chip)
+{
+	struct snd_usb_midi2_interface *umidi;
+	struct snd_usb_midi2_endpoint *ep;
+
+	list_for_each_entry(umidi, &chip->midi_v2_list, list) {
+		umidi->disconnected = 1;
+		list_for_each_entry(ep, &umidi->ep_list, list) {
+			ep->disconnected = 1;
+			kill_midi_urbs(ep, false);
+			drain_urb_queue(ep);
+		}
+	}
+}
+
+/* release the MIDI instance */
+void snd_usb_midi_v2_free_all(struct snd_usb_audio *chip)
+{
+	struct snd_usb_midi2_interface *umidi, *next;
+
+	list_for_each_entry_safe(umidi, next, &chip->midi_v2_list, list)
+		snd_usb_midi_v2_free(umidi);
+}