Merge tag 'usb-for-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing

Felipe writes:

usb: changes for v4.13 merge window

This time around we have a total of 57 non-merge commits. A list of
most important changes follows:

- Improvements to dwc3 tracing interface
- Initial dual-role support for dwc3
- Improvements to how we handle DMA resources in dwc3
- A new f_uac1 implementation which much more flexible
- Removal of AVR32 bits
- Improvements to f_mass_storage driver

13 files changed, 2595 insertions, 1628 deletions

diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
index cb8c225e8549..86e825269947 100644
--- a/drivers/usb/gadget/function/Makefile
+++ b/drivers/usb/gadget/function/Makefile
@@ -32,8 +32,11 @@ usb_f_mass_storage-y		:= f_mass_storage.o storage_common.o
 obj-$(CONFIG_USB_F_MASS_STORAGE)+= usb_f_mass_storage.o
 usb_f_fs-y			:= f_fs.o
 obj-$(CONFIG_USB_F_FS)		+= usb_f_fs.o
-usb_f_uac1-y			:= f_uac1.o u_uac1.o
+obj-$(CONFIG_USB_U_AUDIO)	+= u_audio.o
+usb_f_uac1-y			:= f_uac1.o
 obj-$(CONFIG_USB_F_UAC1)	+= usb_f_uac1.o
+usb_f_uac1_legacy-y		:= f_uac1_legacy.o u_uac1_legacy.o
+obj-$(CONFIG_USB_F_UAC1_LEGACY)	+= usb_f_uac1_legacy.o
 usb_f_uac2-y			:= f_uac2.o
 obj-$(CONFIG_USB_F_UAC2)	+= usb_f_uac2.o
 usb_f_uvc-y			:= f_uvc.o uvc_queue.o uvc_v4l2.o uvc_video.o uvc_configfs.o
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 47dda3450abd..d21874b35cf6 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -127,7 +127,6 @@ struct ffs_ep {
 struct ffs_epfile {
 	/* Protects ep->ep and ep->req. */
 	struct mutex			mutex;
-	wait_queue_head_t		wait;
 
 	struct ffs_data			*ffs;
 	struct ffs_ep			*ep;	/* P: ffs->eps_lock */
@@ -889,7 +888,8 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		if (file->f_flags & O_NONBLOCK)
 			return -EAGAIN;
 
-		ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
+		ret = wait_event_interruptible(
+				epfile->ffs->wait, (ep = epfile->ep));
 		if (ret)
 			return -EINTR;
 	}
@@ -1189,6 +1189,7 @@ static long ffs_epfile_ioctl(struct file *file, unsigned code,
 			     unsigned long value)
 {
 	struct ffs_epfile *epfile = file->private_data;
+	struct ffs_ep *ep;
 	int ret;
 
 	ENTER();
@@ -1196,50 +1197,65 @@ static long ffs_epfile_ioctl(struct file *file, unsigned code,
 	if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
 		return -ENODEV;
 
+	/* Wait for endpoint to be enabled */
+	ep = epfile->ep;
+	if (!ep) {
+		if (file->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+
+		ret = wait_event_interruptible(
+				epfile->ffs->wait, (ep = epfile->ep));
+		if (ret)
+			return -EINTR;
+	}
+
 	spin_lock_irq(&epfile->ffs->eps_lock);
-	if (likely(epfile->ep)) {
-		switch (code) {
-		case FUNCTIONFS_FIFO_STATUS:
-			ret = usb_ep_fifo_status(epfile->ep->ep);
-			break;
-		case FUNCTIONFS_FIFO_FLUSH:
-			usb_ep_fifo_flush(epfile->ep->ep);
-			ret = 0;
-			break;
-		case FUNCTIONFS_CLEAR_HALT:
-			ret = usb_ep_clear_halt(epfile->ep->ep);
-			break;
-		case FUNCTIONFS_ENDPOINT_REVMAP:
-			ret = epfile->ep->num;
-			break;
-		case FUNCTIONFS_ENDPOINT_DESC:
-		{
-			int desc_idx;
-			struct usb_endpoint_descriptor *desc;
 
-			switch (epfile->ffs->gadget->speed) {
-			case USB_SPEED_SUPER:
-				desc_idx = 2;
-				break;
-			case USB_SPEED_HIGH:
-				desc_idx = 1;
-				break;
-			default:
-				desc_idx = 0;
-			}
-			desc = epfile->ep->descs[desc_idx];
+	/* In the meantime, endpoint got disabled or changed. */
+	if (epfile->ep != ep) {
+		spin_unlock_irq(&epfile->ffs->eps_lock);
+		return -ESHUTDOWN;
+	}
 
-			spin_unlock_irq(&epfile->ffs->eps_lock);
-			ret = copy_to_user((void *)value, desc, desc->bLength);
-			if (ret)
-				ret = -EFAULT;
-			return ret;
-		}
+	switch (code) {
+	case FUNCTIONFS_FIFO_STATUS:
+		ret = usb_ep_fifo_status(epfile->ep->ep);
+		break;
+	case FUNCTIONFS_FIFO_FLUSH:
+		usb_ep_fifo_flush(epfile->ep->ep);
+		ret = 0;
+		break;
+	case FUNCTIONFS_CLEAR_HALT:
+		ret = usb_ep_clear_halt(epfile->ep->ep);
+		break;
+	case FUNCTIONFS_ENDPOINT_REVMAP:
+		ret = epfile->ep->num;
+		break;
+	case FUNCTIONFS_ENDPOINT_DESC:
+	{
+		int desc_idx;
+		struct usb_endpoint_descriptor *desc;
+
+		switch (epfile->ffs->gadget->speed) {
+		case USB_SPEED_SUPER:
+			desc_idx = 2;
+			break;
+		case USB_SPEED_HIGH:
+			desc_idx = 1;
+			break;
 		default:
-			ret = -ENOTTY;
+			desc_idx = 0;
 		}
-	} else {
-		ret = -ENODEV;
+		desc = epfile->ep->descs[desc_idx];
+
+		spin_unlock_irq(&epfile->ffs->eps_lock);
+		ret = copy_to_user((void *)value, desc, desc->bLength);
+		if (ret)
+			ret = -EFAULT;
+		return ret;
+	}
+	default:
+		ret = -ENOTTY;
 	}
 	spin_unlock_irq(&epfile->ffs->eps_lock);
 
@@ -1593,7 +1609,8 @@ static void ffs_data_put(struct ffs_data *ffs)
 		pr_info("%s(): freeing\n", __func__);
 		ffs_data_clear(ffs);
 		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
-		       waitqueue_active(&ffs->ep0req_completion.wait));
+		       waitqueue_active(&ffs->ep0req_completion.wait) ||
+		       waitqueue_active(&ffs->wait));
 		kfree(ffs->dev_name);
 		kfree(ffs);
 	}
@@ -1640,6 +1657,7 @@ static struct ffs_data *ffs_data_new(void)
 	mutex_init(&ffs->mutex);
 	spin_lock_init(&ffs->eps_lock);
 	init_waitqueue_head(&ffs->ev.waitq);
+	init_waitqueue_head(&ffs->wait);
 	init_completion(&ffs->ep0req_completion);
 
 	/* XXX REVISIT need to update it in some places, or do we? */
@@ -1761,7 +1779,6 @@ static int ffs_epfiles_create(struct ffs_data *ffs)
 	for (i = 1; i <= count; ++i, ++epfile) {
 		epfile->ffs = ffs;
 		mutex_init(&epfile->mutex);
-		init_waitqueue_head(&epfile->wait);
 		if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
 			sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
 		else
@@ -1786,8 +1803,7 @@ static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
 	ENTER();
 
 	for (; count; --count, ++epfile) {
-		BUG_ON(mutex_is_locked(&epfile->mutex) ||
-		       waitqueue_active(&epfile->wait));
+		BUG_ON(mutex_is_locked(&epfile->mutex));
 		if (epfile->dentry) {
 			d_delete(epfile->dentry);
 			dput(epfile->dentry);
@@ -1874,11 +1890,11 @@ static int ffs_func_eps_enable(struct ffs_function *func)
 			break;
 		}
 
-		wake_up(&epfile->wait);
-
 		++ep;
 		++epfile;
 	}
+
+	wake_up_interruptible(&ffs->wait);
 	spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
 
 	return ret;
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 74d57d6994da..e80b9c123a9d 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -260,12 +260,13 @@ struct fsg_common {
 	struct usb_gadget	*gadget;
 	struct usb_composite_dev *cdev;
 	struct fsg_dev		*fsg, *new_fsg;
+	wait_queue_head_t	io_wait;
 	wait_queue_head_t	fsg_wait;
 
 	/* filesem protects: backing files in use */
 	struct rw_semaphore	filesem;
 
-	/* lock protects: state, all the req_busy's */
+	/* lock protects: state and thread_task */
 	spinlock_t		lock;
 
 	struct usb_ep		*ep0;		/* Copy of gadget->ep0 */
@@ -303,7 +304,6 @@ struct fsg_common {
 	unsigned int		running:1;
 	unsigned int		sysfs:1;
 
-	int			thread_wakeup_needed;
 	struct completion	thread_notifier;
 	struct task_struct	*thread_task;
 
@@ -355,7 +355,7 @@ typedef void (*fsg_routine_t)(struct fsg_dev *);
 
 static int exception_in_progress(struct fsg_common *common)
 {
-	return common->state > FSG_STATE_IDLE;
+	return common->state > FSG_STATE_NORMAL;
 }
 
 /* Make bulk-out requests be divisible by the maxpacket size */
@@ -393,20 +393,6 @@ static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 
 /* These routines may be called in process context or in_irq */
 
-/* Caller must hold fsg->lock */
-static void wakeup_thread(struct fsg_common *common)
-{
-	/*
-	 * Ensure the reading of thread_wakeup_needed
-	 * and the writing of bh->state are completed
-	 */
-	smp_mb();
-	/* Tell the main thread that something has happened */
-	common->thread_wakeup_needed = 1;
-	if (common->thread_task)
-		wake_up_process(common->thread_task);
-}
-
 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
 {
 	unsigned long		flags;
@@ -460,13 +446,9 @@ static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
 	if (req->status == -ECONNRESET)		/* Request was cancelled */
 		usb_ep_fifo_flush(ep);
 
-	/* Hold the lock while we update the request and buffer states */
-	smp_wmb();
-	spin_lock(&common->lock);
-	bh->inreq_busy = 0;
-	bh->state = BUF_STATE_EMPTY;
-	wakeup_thread(common);
-	spin_unlock(&common->lock);
+	/* Synchronize with the smp_load_acquire() in sleep_thread() */
+	smp_store_release(&bh->state, BUF_STATE_EMPTY);
+	wake_up(&common->io_wait);
 }
 
 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
@@ -481,13 +463,9 @@ static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 	if (req->status == -ECONNRESET)		/* Request was cancelled */
 		usb_ep_fifo_flush(ep);
 
-	/* Hold the lock while we update the request and buffer states */
-	smp_wmb();
-	spin_lock(&common->lock);
-	bh->outreq_busy = 0;
-	bh->state = BUF_STATE_FULL;
-	wakeup_thread(common);
-	spin_unlock(&common->lock);
+	/* Synchronize with the smp_load_acquire() in sleep_thread() */
+	smp_store_release(&bh->state, BUF_STATE_FULL);
+	wake_up(&common->io_wait);
 }
 
 static int _fsg_common_get_max_lun(struct fsg_common *common)
@@ -532,7 +510,7 @@ static int fsg_setup(struct usb_function *f,
 		 * and reinitialize our state.
 		 */
 		DBG(fsg, "bulk reset request\n");
-		raise_exception(fsg->common, FSG_STATE_RESET);
+		raise_exception(fsg->common, FSG_STATE_PROTOCOL_RESET);
 		return USB_GADGET_DELAYED_STATUS;
 
 	case US_BULK_GET_MAX_LUN:
@@ -563,43 +541,39 @@ static int fsg_setup(struct usb_function *f,
 /* All the following routines run in process context */
 
 /* Use this for bulk or interrupt transfers, not ep0 */
-static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
-			   struct usb_request *req, int *pbusy,
-			   enum fsg_buffer_state *state)
+static int start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
+			   struct usb_request *req)
 {
 	int	rc;
 
 	if (ep == fsg->bulk_in)
 		dump_msg(fsg, "bulk-in", req->buf, req->length);
 
-	spin_lock_irq(&fsg->common->lock);
-	*pbusy = 1;
-	*state = BUF_STATE_BUSY;
-	spin_unlock_irq(&fsg->common->lock);
-
 	rc = usb_ep_queue(ep, req, GFP_KERNEL);
-	if (rc == 0)
-		return;  /* All good, we're done */
-
-	*pbusy = 0;
-	*state = BUF_STATE_EMPTY;
+	if (rc) {
 
-	/* We can't do much more than wait for a reset */
+		/* We can't do much more than wait for a reset */
+		req->status = rc;
 
-	/*
-	 * Note: currently the net2280 driver fails zero-length
-	 * submissions if DMA is enabled.
-	 */
-	if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP && req->length == 0))
-		WARNING(fsg, "error in submission: %s --> %d\n", ep->name, rc);
+		/*
+		 * Note: currently the net2280 driver fails zero-length
+		 * submissions if DMA is enabled.
+		 */
+		if (rc != -ESHUTDOWN &&
+				!(rc == -EOPNOTSUPP && req->length == 0))
+			WARNING(fsg, "error in submission: %s --> %d\n",
+					ep->name, rc);
+	}
+	return rc;
 }
 
 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 	if (!fsg_is_set(common))
 		return false;
-	start_transfer(common->fsg, common->fsg->bulk_in,
-		       bh->inreq, &bh->inreq_busy, &bh->state);
+	bh->state = BUF_STATE_SENDING;
+	if (start_transfer(common->fsg, common->fsg->bulk_in, bh->inreq))
+		bh->state = BUF_STATE_EMPTY;
 	return true;
 }
 
@@ -607,37 +581,31 @@ static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 	if (!fsg_is_set(common))
 		return false;
-	start_transfer(common->fsg, common->fsg->bulk_out,
-		       bh->outreq, &bh->outreq_busy, &bh->state);
+	bh->state = BUF_STATE_RECEIVING;
+	if (start_transfer(common->fsg, common->fsg->bulk_out, bh->outreq))
+		bh->state = BUF_STATE_FULL;
 	return true;
 }
 
-static int sleep_thread(struct fsg_common *common, bool can_freeze)
+static int sleep_thread(struct fsg_common *common, bool can_freeze,
+		struct fsg_buffhd *bh)
 {
-	int	rc = 0;
-
-	/* Wait until a signal arrives or we are woken up */
-	for (;;) {
-		if (can_freeze)
-			try_to_freeze();
-		set_current_state(TASK_INTERRUPTIBLE);
-		if (signal_pending(current)) {
-			rc = -EINTR;
-			break;
-		}
-		if (common->thread_wakeup_needed)
-			break;
-		schedule();
-	}
-	__set_current_state(TASK_RUNNING);
-	common->thread_wakeup_needed = 0;
+	int	rc;
 
-	/*
-	 * Ensure the writing of thread_wakeup_needed
-	 * and the reading of bh->state are completed
-	 */
-	smp_mb();
-	return rc;
+	/* Wait until a signal arrives or bh is no longer busy */
+	if (can_freeze)
+		/*
+		 * synchronize with the smp_store_release(&bh->state) in
+		 * bulk_in_complete() or bulk_out_complete()
+		 */
+		rc = wait_event_freezable(common->io_wait,
+				bh && smp_load_acquire(&bh->state) >=
+					BUF_STATE_EMPTY);
+	else
+		rc = wait_event_interruptible(common->io_wait,
+				bh && smp_load_acquire(&bh->state) >=
+					BUF_STATE_EMPTY);
+	return rc ? -EINTR : 0;
 }
 
 
@@ -697,11 +665,9 @@ static int do_read(struct fsg_common *common)
 
 		/* Wait for the next buffer to become available */
 		bh = common->next_buffhd_to_fill;
-		while (bh->state != BUF_STATE_EMPTY) {
-			rc = sleep_thread(common, false);
-			if (rc)
-				return rc;
-		}
+		rc = sleep_thread(common, false, bh);
+		if (rc)
+			return rc;
 
 		/*
 		 * If we were asked to read past the end of file,
@@ -878,84 +844,80 @@ static int do_write(struct fsg_common *common)
 		bh = common->next_buffhd_to_drain;
 		if (bh->state == BUF_STATE_EMPTY && !get_some_more)
 			break;			/* We stopped early */
-		if (bh->state == BUF_STATE_FULL) {
-			smp_rmb();
-			common->next_buffhd_to_drain = bh->next;
-			bh->state = BUF_STATE_EMPTY;
-
-			/* Did something go wrong with the transfer? */
-			if (bh->outreq->status != 0) {
-				curlun->sense_data = SS_COMMUNICATION_FAILURE;
-				curlun->sense_data_info =
+
+		/* Wait for the data to be received */
+		rc = sleep_thread(common, false, bh);
+		if (rc)
+			return rc;
+
+		common->next_buffhd_to_drain = bh->next;
+		bh->state = BUF_STATE_EMPTY;
+
+		/* Did something go wrong with the transfer? */
+		if (bh->outreq->status != 0) {
+			curlun->sense_data = SS_COMMUNICATION_FAILURE;
+			curlun->sense_data_info =
 					file_offset >> curlun->blkbits;
-				curlun->info_valid = 1;
-				break;
-			}
+			curlun->info_valid = 1;
+			break;
+		}
 
-			amount = bh->outreq->actual;
-			if (curlun->file_length - file_offset < amount) {
-				LERROR(curlun,
-				       "write %u @ %llu beyond end %llu\n",
+		amount = bh->outreq->actual;
+		if (curlun->file_length - file_offset < amount) {
+			LERROR(curlun, "write %u @ %llu beyond end %llu\n",
 				       amount, (unsigned long long)file_offset,
 				       (unsigned long long)curlun->file_length);
-				amount = curlun->file_length - file_offset;
-			}
+			amount = curlun->file_length - file_offset;
+		}
 
-			/* Don't accept excess data.  The spec doesn't say
-			 * what to do in this case.  We'll ignore the error.
-			 */
-			amount = min(amount, bh->bulk_out_intended_length);
-
-			/* Don't write a partial block */
-			amount = round_down(amount, curlun->blksize);
-			if (amount == 0)
-				goto empty_write;
-
-			/* Perform the write */
-			file_offset_tmp = file_offset;
-			nwritten = vfs_write(curlun->filp,
-					     (char __user *)bh->buf,
-					     amount, &file_offset_tmp);
-			VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
-			      (unsigned long long)file_offset, (int)nwritten);
-			if (signal_pending(current))
-				return -EINTR;		/* Interrupted! */
-
-			if (nwritten < 0) {
-				LDBG(curlun, "error in file write: %d\n",
-				     (int)nwritten);
-				nwritten = 0;
-			} else if (nwritten < amount) {
-				LDBG(curlun, "partial file write: %d/%u\n",
-				     (int)nwritten, amount);
-				nwritten = round_down(nwritten, curlun->blksize);
-			}
-			file_offset += nwritten;
-			amount_left_to_write -= nwritten;
-			common->residue -= nwritten;
+		/*
+		 * Don't accept excess data.  The spec doesn't say
+		 * what to do in this case.  We'll ignore the error.
+		 */
+		amount = min(amount, bh->bulk_out_intended_length);
 
-			/* If an error occurred, report it and its position */
-			if (nwritten < amount) {
-				curlun->sense_data = SS_WRITE_ERROR;
-				curlun->sense_data_info =
+		/* Don't write a partial block */
+		amount = round_down(amount, curlun->blksize);
+		if (amount == 0)
+			goto empty_write;
+
+		/* Perform the write */
+		file_offset_tmp = file_offset;
+		nwritten = vfs_write(curlun->filp, (char __user *)bh->buf,
+				amount, &file_offset_tmp);
+		VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
+				(unsigned long long)file_offset, (int)nwritten);
+		if (signal_pending(current))
+			return -EINTR;		/* Interrupted! */
+
+		if (nwritten < 0) {
+			LDBG(curlun, "error in file write: %d\n",
+					(int) nwritten);
+			nwritten = 0;
+		} else if (nwritten < amount) {
+			LDBG(curlun, "partial file write: %d/%u\n",
+					(int) nwritten, amount);
+			nwritten = round_down(nwritten, curlun->blksize);
+		}
+		file_offset += nwritten;
+		amount_left_to_write -= nwritten;
+		common->residue -= nwritten;
+
+		/* If an error occurred, report it and its position */
+		if (nwritten < amount) {
+			curlun->sense_data = SS_WRITE_ERROR;
+			curlun->sense_data_info =
 					file_offset >> curlun->blkbits;
-				curlun->info_valid = 1;
-				break;
-			}
+			curlun->info_valid = 1;
+			break;
+		}
 
  empty_write:
-			/* Did the host decide to stop early? */
-			if (bh->outreq->actual < bh->bulk_out_intended_length) {
-				common->short_packet_received = 1;
-				break;
-			}
-			continue;
+		/* Did the host decide to stop early? */
+		if (bh->outreq->actual < bh->bulk_out_intended_length) {
+			common->short_packet_received = 1;
+			break;
 		}
-
-		/* Wait for something to happen */
-		rc = sleep_thread(common, false);
-		if (rc)
-			return rc;
 	}
 
 	return -EIO;		/* No default reply */
@@ -1480,7 +1442,7 @@ static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
 
 static int throw_away_data(struct fsg_common *common)
 {
-	struct fsg_buffhd	*bh;
+	struct fsg_buffhd	*bh, *bh2;
 	u32			amount;
 	int			rc;
 
@@ -1488,26 +1450,10 @@ static int throw_away_data(struct fsg_common *common)
 	     bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
 	     bh = common->next_buffhd_to_drain) {
 
-		/* Throw away the data in a filled buffer */
-		if (bh->state == BUF_STATE_FULL) {
-			smp_rmb();
-			bh->state = BUF_STATE_EMPTY;
-			common->next_buffhd_to_drain = bh->next;
-
-			/* A short packet or an error ends everything */
-			if (bh->outreq->actual < bh->bulk_out_intended_length ||
-			    bh->outreq->status != 0) {
-				raise_exception(common,
-						FSG_STATE_ABORT_BULK_OUT);
-				return -EINTR;
-			}
-			continue;
-		}
-
 		/* Try to submit another request if we need one */
-		bh = common->next_buffhd_to_fill;
-		if (bh->state == BUF_STATE_EMPTY
-		 && common->usb_amount_left > 0) {
+		bh2 = common->next_buffhd_to_fill;
+		if (bh2->state == BUF_STATE_EMPTY &&
+				common->usb_amount_left > 0) {
 			amount = min(common->usb_amount_left, FSG_BUFLEN);
 
 			/*
@@ -1515,19 +1461,30 @@ static int throw_away_data(struct fsg_common *common)
 			 * equal to the buffer size, which is divisible by
 			 * the bulk-out maxpacket size.
 			 */
-			set_bulk_out_req_length(common, bh, amount);
-			if (!start_out_transfer(common, bh))
+			set_bulk_out_req_length(common, bh2, amount);
+			if (!start_out_transfer(common, bh2))
 				/* Dunno what to do if common->fsg is NULL */
 				return -EIO;
-			common->next_buffhd_to_fill = bh->next;
+			common->next_buffhd_to_fill = bh2->next;
 			common->usb_amount_left -= amount;
 			continue;
 		}
 
-		/* Otherwise wait for something to happen */
-		rc = sleep_thread(common, true);
+		/* Wait for the data to be received */
+		rc = sleep_thread(common, false, bh);
 		if (rc)
 			return rc;
+
+		/* Throw away the data in a filled buffer */
+		bh->state = BUF_STATE_EMPTY;
+		common->next_buffhd_to_drain = bh->next;
+
+		/* A short packet or an error ends everything */
+		if (bh->outreq->actual < bh->bulk_out_intended_length ||
+				bh->outreq->status != 0) {
+			raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
+			return -EINTR;
+		}
 	}
 	return 0;
 }
@@ -1634,7 +1591,7 @@ static int finish_reply(struct fsg_common *common)
 	return rc;
 }
 
-static int send_status(struct fsg_common *common)
+static void send_status(struct fsg_common *common)
 {
 	struct fsg_lun		*curlun = common->curlun;
 	struct fsg_buffhd	*bh;
@@ -1645,11 +1602,9 @@ static int send_status(struct fsg_common *common)
 
 	/* Wait for the next buffer to become available */
 	bh = common->next_buffhd_to_fill;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
+	rc = sleep_thread(common, false, bh);
+	if (rc)
+		return;
 
 	if (curlun) {
 		sd = curlun->sense_data;
@@ -1683,10 +1638,10 @@ static int send_status(struct fsg_common *common)
 	bh->inreq->zero = 0;
 	if (!start_in_transfer(common, bh))
 		/* Don't know what to do if common->fsg is NULL */
-		return -EIO;
+		return;
 
 	common->next_buffhd_to_fill = bh->next;
-	return 0;
+	return;
 }
 
 
@@ -1848,11 +1803,10 @@ static int do_scsi_command(struct fsg_common *common)
 	/* Wait for the next buffer to become available for data or status */
 	bh = common->next_buffhd_to_fill;
 	common->next_buffhd_to_drain = bh;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
+	rc = sleep_thread(common, false, bh);
+	if (rc)
+		return rc;
+
 	common->phase_error = 0;
 	common->short_packet_received = 0;
 
@@ -2195,11 +2149,9 @@ static int get_next_command(struct fsg_common *common)
 
 	/* Wait for the next buffer to become available */
 	bh = common->next_buffhd_to_fill;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
+	rc = sleep_thread(common, true, bh);
+	if (rc)
+		return rc;
 
 	/* Queue a request to read a Bulk-only CBW */
 	set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
@@ -2214,12 +2166,10 @@ static int get_next_command(struct fsg_common *common)
 	 */
 
 	/* Wait for the CBW to arrive */
-	while (bh->state != BUF_STATE_FULL) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-	smp_rmb();
+	rc = sleep_thread(common, true, bh);
+	if (rc)
+		return rc;
+
 	rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
 	bh->state = BUF_STATE_EMPTY;
 
@@ -2371,9 +2321,11 @@ static void handle_exception(struct fsg_common *common)
 		if (!sig)
 			break;
 		if (sig != SIGUSR1) {
+			spin_lock_irq(&common->lock);
 			if (common->state < FSG_STATE_EXIT)
 				DBG(common, "Main thread exiting on signal\n");
-			raise_exception(common, FSG_STATE_EXIT);
+			common->state = FSG_STATE_EXIT;
+			spin_unlock_irq(&common->lock);
 		}
 	}
 
@@ -2381,23 +2333,14 @@ static void handle_exception(struct fsg_common *common)
 	if (likely(common->fsg)) {
 		for (i = 0; i < common->fsg_num_buffers; ++i) {
 			bh = &common->buffhds[i];
-			if (bh->inreq_busy)
+			if (bh->state == BUF_STATE_SENDING)
 				usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
-			if (bh->outreq_busy)
+			if (bh->state == BUF_STATE_RECEIVING)
 				usb_ep_dequeue(common->fsg->bulk_out,
 					       bh->outreq);
-		}
 
-		/* Wait until everything is idle */
-		for (;;) {
-			int num_active = 0;
-			for (i = 0; i < common->fsg_num_buffers; ++i) {
-				bh = &common->buffhds[i];
-				num_active += bh->inreq_busy + bh->outreq_busy;
-			}
-			if (num_active == 0)
-				break;
-			if (sleep_thread(common, true))
+			/* Wait for a transfer to become idle */
+			if (sleep_thread(common, false, bh))
 				return;
 		}
 
@@ -2422,10 +2365,9 @@ static void handle_exception(struct fsg_common *common)
 	common->next_buffhd_to_drain = &common->buffhds[0];
 	exception_req_tag = common->exception_req_tag;
 	old_state = common->state;
+	common->state = FSG_STATE_NORMAL;
 
-	if (old_state == FSG_STATE_ABORT_BULK_OUT)
-		common->state = FSG_STATE_STATUS_PHASE;
-	else {
+	if (old_state != FSG_STATE_ABORT_BULK_OUT) {
 		for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
 			curlun = common->luns[i];
 			if (!curlun)
@@ -2436,21 +2378,19 @@ static void handle_exception(struct fsg_common *common)
 			curlun->sense_data_info = 0;
 			curlun->info_valid = 0;
 		}
-		common->state = FSG_STATE_IDLE;
 	}
 	spin_unlock_irq(&common->lock);
 
 	/* Carry out any extra actions required for the exception */
 	switch (old_state) {
+	case FSG_STATE_NORMAL:
+		break;
+
 	case FSG_STATE_ABORT_BULK_OUT:
 		send_status(common);
-		spin_lock_irq(&common->lock);
-		if (common->state == FSG_STATE_STATUS_PHASE)
-			common->state = FSG_STATE_IDLE;
-		spin_unlock_irq(&common->lock);
 		break;
 
-	case FSG_STATE_RESET:
+	case FSG_STATE_PROTOCOL_RESET:
 		/*
 		 * In case we were forced against our will to halt a
 		 * bulk endpoint, clear the halt now.  (The SuperH UDC
@@ -2483,19 +2423,13 @@ static void handle_exception(struct fsg_common *common)
 		break;
 
 	case FSG_STATE_EXIT:
-	case FSG_STATE_TERMINATED:
 		do_set_interface(common, NULL);		/* Free resources */
 		spin_lock_irq(&common->lock);
 		common->state = FSG_STATE_TERMINATED;	/* Stop the thread */
 		spin_unlock_irq(&common->lock);
 		break;
 
-	case FSG_STATE_INTERFACE_CHANGE:
-	case FSG_STATE_DISCONNECT:
-	case FSG_STATE_COMMAND_PHASE:
-	case FSG_STATE_DATA_PHASE:
-	case FSG_STATE_STATUS_PHASE:
-	case FSG_STATE_IDLE:
+	case FSG_STATE_TERMINATED:
 		break;
 	}
 }
@@ -2534,33 +2468,17 @@ static int fsg_main_thread(void *common_)
 		}
 
 		if (!common->running) {
-			sleep_thread(common, true);
+			sleep_thread(common, true, NULL);
 			continue;
 		}
 
-		if (get_next_command(common))
+		if (get_next_command(common) || exception_in_progress(common))
 			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_DATA_PHASE;
-		spin_unlock_irq(&common->lock);
-
-		if (do_scsi_command(common) || finish_reply(common))
+		if (do_scsi_command(common) || exception_in_progress(common))
 			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_STATUS_PHASE;
-		spin_unlock_irq(&common->lock);
-
-		if (send_status(common))
+		if (finish_reply(common) || exception_in_progress(common))
 			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_IDLE;
-		spin_unlock_irq(&common->lock);
+		send_status(common);
 	}
 
 	spin_lock_irq(&common->lock);
@@ -2680,6 +2598,7 @@ static struct fsg_common *fsg_common_setup(struct fsg_common *common)
 	spin_lock_init(&common->lock);
 	kref_init(&common->ref);
 	init_completion(&common->thread_notifier);
+	init_waitqueue_head(&common->io_wait);
 	init_waitqueue_head(&common->fsg_wait);
 	common->state = FSG_STATE_TERMINATED;
 	memset(common->luns, 0, sizeof(common->luns));
@@ -2981,7 +2900,6 @@ static void fsg_common_release(struct kref *ref)
 	if (common->state != FSG_STATE_TERMINATED) {
 		raise_exception(common, FSG_STATE_EXIT);
 		wait_for_completion(&common->thread_notifier);
-		common->thread_task = NULL;
 	}
 
 	for (i = 0; i < ARRAY_SIZE(common->luns); ++i) {
@@ -3030,11 +2948,11 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
 	}
 
 	if (!common->thread_task) {
-		common->state = FSG_STATE_IDLE;
+		common->state = FSG_STATE_NORMAL;
 		common->thread_task =
 			kthread_create(fsg_main_thread, common, "file-storage");
 		if (IS_ERR(common->thread_task)) {
-			int ret = PTR_ERR(common->thread_task);
+			ret = PTR_ERR(common->thread_task);
 			common->thread_task = NULL;
 			common->state = FSG_STATE_TERMINATED;
 			return ret;
diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c
index f2ac0cbc29a4..8656f84e17d9 100644
--- a/drivers/usb/gadget/function/f_uac1.c
+++ b/drivers/usb/gadget/function/f_uac1.c
@@ -1,24 +1,38 @@
 /*
- * f_audio.c -- USB Audio class function driver
-  *
- * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
- * Copyright (C) 2008 Analog Devices, Inc
+ * f_uac1.c -- USB Audio Class 1.0 Function (using u_audio API)
  *
- * Enter bugs at http://blackfin.uclinux.org/
+ * Copyright (C) 2016 Ruslan Bilovol <ruslan.bilovol@gmail.com>
  *
- * Licensed under the GPL-2 or later.
+ * This driver doesn't expect any real Audio codec to be present
+ * on the device - the audio streams are simply sinked to and
+ * sourced from a virtual ALSA sound card created.
+ *
+ * This file is based on f_uac1.c which is
+ *   Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
+ *   Copyright (C) 2008 Analog Devices, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
  */
 
-#include <linux/slab.h>
-#include <linux/kernel.h>
+#include <linux/usb/audio.h>
 #include <linux/module.h>
-#include <linux/device.h>
-#include <linux/atomic.h>
 
+#include "u_audio.h"
 #include "u_uac1.h"
 
-static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
-static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
+struct f_uac1 {
+	struct g_audio g_audio;
+	u8 ac_intf, as_in_intf, as_out_intf;
+	u8 ac_alt, as_in_alt, as_out_alt;	/* needed for get_alt() */
+};
+
+static inline struct f_uac1 *func_to_uac1(struct usb_function *f)
+{
+	return container_of(f, struct f_uac1, g_audio.func);
+}
 
 /*
  * DESCRIPTORS ... most are static, but strings and full
@@ -26,12 +40,17 @@ static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
  */
 
 /*
- * We have two interfaces- AudioControl and AudioStreaming
- * TODO: only supcard playback currently
+ * We have three interfaces - one AudioControl and two AudioStreaming
+ *
+ * The driver implements a simple UAC_1 topology.
+ * USB-OUT -> IT_1 -> OT_2 -> ALSA_Capture
+ * ALSA_Playback -> IT_3 -> OT_4 -> USB-IN
  */
-#define F_AUDIO_AC_INTERFACE	0
-#define F_AUDIO_AS_INTERFACE	1
-#define F_AUDIO_NUM_INTERFACES	1
+#define F_AUDIO_AC_INTERFACE		0
+#define F_AUDIO_AS_OUT_INTERFACE	1
+#define F_AUDIO_AS_IN_INTERFACE		2
+/* Number of streaming interfaces */
+#define F_AUDIO_NUM_INTERFACES		2
 
 /* B.3.1  Standard AC Interface Descriptor */
 static struct usb_interface_descriptor ac_interface_desc = {
@@ -46,89 +65,91 @@ static struct usb_interface_descriptor ac_interface_desc = {
  * The number of AudioStreaming and MIDIStreaming interfaces
  * in the Audio Interface Collection
  */
-DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
+DECLARE_UAC_AC_HEADER_DESCRIPTOR(2);
 
 #define UAC_DT_AC_HEADER_LENGTH	UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
-/* 1 input terminal, 1 output terminal and 1 feature unit */
-#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
-	+ UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
+/* 2 input terminals and 2 output terminals */
+#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH \
+	+ 2*UAC_DT_INPUT_TERMINAL_SIZE + 2*UAC_DT_OUTPUT_TERMINAL_SIZE)
 /* B.3.2  Class-Specific AC Interface Descriptor */
-static struct uac1_ac_header_descriptor_1 ac_header_desc = {
+static struct uac1_ac_header_descriptor_2 ac_header_desc = {
 	.bLength =		UAC_DT_AC_HEADER_LENGTH,
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_HEADER,
-	.bcdADC =		__constant_cpu_to_le16(0x0100),
-	.wTotalLength =		__constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
+	.bcdADC =		cpu_to_le16(0x0100),
+	.wTotalLength =		cpu_to_le16(UAC_DT_TOTAL_LENGTH),
 	.bInCollection =	F_AUDIO_NUM_INTERFACES,
 	.baInterfaceNr = {
-	/* Interface number of the first AudioStream interface */
+	/* Interface number of the AudioStream interfaces */
 		[0] =		1,
+		[1] =		2,
 	}
 };
 
-#define INPUT_TERMINAL_ID	1
-static struct uac_input_terminal_descriptor input_terminal_desc = {
+#define USB_OUT_IT_ID	1
+static struct uac_input_terminal_descriptor usb_out_it_desc = {
 	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
-	.bTerminalID =		INPUT_TERMINAL_ID,
+	.bTerminalID =		USB_OUT_IT_ID,
 	.wTerminalType =	UAC_TERMINAL_STREAMING,
 	.bAssocTerminal =	0,
 	.wChannelConfig =	0x3,
 };
 
-DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
-
-#define FEATURE_UNIT_ID		2
-static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
-	.bLength		= UAC_DT_FEATURE_UNIT_SIZE(0),
+#define IO_OUT_OT_ID	2
+static struct uac1_output_terminal_descriptor io_out_ot_desc = {
+	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
 	.bDescriptorType	= USB_DT_CS_INTERFACE,
-	.bDescriptorSubtype	= UAC_FEATURE_UNIT,
-	.bUnitID		= FEATURE_UNIT_ID,
-	.bSourceID		= INPUT_TERMINAL_ID,
-	.bControlSize		= 2,
-	.bmaControls[0]		= (UAC_FU_MUTE | UAC_FU_VOLUME),
+	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
+	.bTerminalID		= IO_OUT_OT_ID,
+	.wTerminalType		= UAC_OUTPUT_TERMINAL_SPEAKER,
+	.bAssocTerminal		= 0,
+	.bSourceID		= USB_OUT_IT_ID,
 };
 
-static struct usb_audio_control mute_control = {
-	.list = LIST_HEAD_INIT(mute_control.list),
-	.name = "Mute Control",
-	.type = UAC_FU_MUTE,
-	/* Todo: add real Mute control code */
-	.set = generic_set_cmd,
-	.get = generic_get_cmd,
+#define IO_IN_IT_ID	3
+static struct uac_input_terminal_descriptor io_in_it_desc = {
+	.bLength		= UAC_DT_INPUT_TERMINAL_SIZE,
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype	= UAC_INPUT_TERMINAL,
+	.bTerminalID		= IO_IN_IT_ID,
+	.wTerminalType		= UAC_INPUT_TERMINAL_MICROPHONE,
+	.bAssocTerminal		= 0,
+	.wChannelConfig		= 0x3,
 };
 
-static struct usb_audio_control volume_control = {
-	.list = LIST_HEAD_INIT(volume_control.list),
-	.name = "Volume Control",
-	.type = UAC_FU_VOLUME,
-	/* Todo: add real Volume control code */
-	.set = generic_set_cmd,
-	.get = generic_get_cmd,
+#define USB_IN_OT_ID	4
+static struct uac1_output_terminal_descriptor usb_in_ot_desc = {
+	.bLength =		UAC_DT_OUTPUT_TERMINAL_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_OUTPUT_TERMINAL,
+	.bTerminalID =		USB_IN_OT_ID,
+	.wTerminalType =	UAC_TERMINAL_STREAMING,
+	.bAssocTerminal =	0,
+	.bSourceID =		IO_IN_IT_ID,
 };
 
-static struct usb_audio_control_selector feature_unit = {
-	.list = LIST_HEAD_INIT(feature_unit.list),
-	.id = FEATURE_UNIT_ID,
-	.name = "Mute & Volume Control",
-	.type = UAC_FEATURE_UNIT,
-	.desc = (struct usb_descriptor_header *)&feature_unit_desc,
+/* B.4.1  Standard AS Interface Descriptor */
+static struct usb_interface_descriptor as_out_interface_alt_0_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
 };
 
-#define OUTPUT_TERMINAL_ID	3
-static struct uac1_output_terminal_descriptor output_terminal_desc = {
-	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
-	.bDescriptorType	= USB_DT_CS_INTERFACE,
-	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
-	.bTerminalID		= OUTPUT_TERMINAL_ID,
-	.wTerminalType		= UAC_OUTPUT_TERMINAL_SPEAKER,
-	.bAssocTerminal		= FEATURE_UNIT_ID,
-	.bSourceID		= FEATURE_UNIT_ID,
+static struct usb_interface_descriptor as_out_interface_alt_1_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	1,
+	.bNumEndpoints =	1,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
 };
 
-/* B.4.1  Standard AS Interface Descriptor */
-static struct usb_interface_descriptor as_interface_alt_0_desc = {
+static struct usb_interface_descriptor as_in_interface_alt_0_desc = {
 	.bLength =		USB_DT_INTERFACE_SIZE,
 	.bDescriptorType =	USB_DT_INTERFACE,
 	.bAlternateSetting =	0,
@@ -137,7 +158,7 @@ static struct usb_interface_descriptor as_interface_alt_0_desc = {
 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
 };
 
-static struct usb_interface_descriptor as_interface_alt_1_desc = {
+static struct usb_interface_descriptor as_in_interface_alt_1_desc = {
 	.bLength =		USB_DT_INTERFACE_SIZE,
 	.bDescriptorType =	USB_DT_INTERFACE,
 	.bAlternateSetting =	1,
@@ -147,18 +168,27 @@ static struct usb_interface_descriptor as_interface_alt_1_desc = {
 };
 
 /* B.4.2  Class-Specific AS Interface Descriptor */
-static struct uac1_as_header_descriptor as_header_desc = {
+static struct uac1_as_header_descriptor as_out_header_desc = {
 	.bLength =		UAC_DT_AS_HEADER_SIZE,
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_AS_GENERAL,
-	.bTerminalLink =	INPUT_TERMINAL_ID,
+	.bTerminalLink =	USB_OUT_IT_ID,
+	.bDelay =		1,
+	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
+};
+
+static struct uac1_as_header_descriptor as_in_header_desc = {
+	.bLength =		UAC_DT_AS_HEADER_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_AS_GENERAL,
+	.bTerminalLink =	USB_IN_OT_ID,
 	.bDelay =		1,
 	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
 };
 
 DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
 
-static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
+static struct uac_format_type_i_discrete_descriptor_1 as_out_type_i_desc = {
 	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 	.bDescriptorType =	USB_DT_CS_INTERFACE,
 	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
@@ -184,48 +214,97 @@ static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
 	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
 	.bDescriptorType =	USB_DT_CS_ENDPOINT,
 	.bDescriptorSubtype =	UAC_EP_GENERAL,
-	.bmAttributes = 	1,
+	.bmAttributes =		1,
 	.bLockDelayUnits =	1,
-	.wLockDelay =		__constant_cpu_to_le16(1),
+	.wLockDelay =		cpu_to_le16(1),
+};
+
+static struct uac_format_type_i_discrete_descriptor_1 as_in_type_i_desc = {
+	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
+	.bFormatType =		UAC_FORMAT_TYPE_I,
+	.bSubframeSize =	2,
+	.bBitResolution =	16,
+	.bSamFreqType =		1,
+};
+
+/* Standard ISO OUT Endpoint Descriptor */
+static struct usb_endpoint_descriptor as_in_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_SYNC_ASYNC
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
+	.bInterval =		4,
+};
+
+/* Class-specific AS ISO OUT Endpoint Descriptor */
+static struct uac_iso_endpoint_descriptor as_iso_in_desc = {
+	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
+	.bDescriptorType =	USB_DT_CS_ENDPOINT,
+	.bDescriptorSubtype =	UAC_EP_GENERAL,
+	.bmAttributes =		1,
+	.bLockDelayUnits =	0,
+	.wLockDelay =		0,
 };
 
 static struct usb_descriptor_header *f_audio_desc[] = {
 	(struct usb_descriptor_header *)&ac_interface_desc,
 	(struct usb_descriptor_header *)&ac_header_desc,
 
-	(struct usb_descriptor_header *)&input_terminal_desc,
-	(struct usb_descriptor_header *)&output_terminal_desc,
-	(struct usb_descriptor_header *)&feature_unit_desc,
+	(struct usb_descriptor_header *)&usb_out_it_desc,
+	(struct usb_descriptor_header *)&io_out_ot_desc,
+	(struct usb_descriptor_header *)&io_in_it_desc,
+	(struct usb_descriptor_header *)&usb_in_ot_desc,
 
-	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
-	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
-	(struct usb_descriptor_header *)&as_header_desc,
+	(struct usb_descriptor_header *)&as_out_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_out_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_out_header_desc,
 
-	(struct usb_descriptor_header *)&as_type_i_desc,
+	(struct usb_descriptor_header *)&as_out_type_i_desc,
 
 	(struct usb_descriptor_header *)&as_out_ep_desc,
 	(struct usb_descriptor_header *)&as_iso_out_desc,
+
+	(struct usb_descriptor_header *)&as_in_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_in_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_in_header_desc,
+
+	(struct usb_descriptor_header *)&as_in_type_i_desc,
+
+	(struct usb_descriptor_header *)&as_in_ep_desc,
+	(struct usb_descriptor_header *)&as_iso_in_desc,
 	NULL,
 };
 
 enum {
 	STR_AC_IF,
-	STR_INPUT_TERMINAL,
-	STR_INPUT_TERMINAL_CH_NAMES,
-	STR_FEAT_DESC_0,
-	STR_OUTPUT_TERMINAL,
-	STR_AS_IF_ALT0,
-	STR_AS_IF_ALT1,
+	STR_USB_OUT_IT,
+	STR_USB_OUT_IT_CH_NAMES,
+	STR_IO_OUT_OT,
+	STR_IO_IN_IT,
+	STR_IO_IN_IT_CH_NAMES,
+	STR_USB_IN_OT,
+	STR_AS_OUT_IF_ALT0,
+	STR_AS_OUT_IF_ALT1,
+	STR_AS_IN_IF_ALT0,
+	STR_AS_IN_IF_ALT1,
 };
 
 static struct usb_string strings_uac1[] = {
 	[STR_AC_IF].s = "AC Interface",
-	[STR_INPUT_TERMINAL].s = "Input terminal",
-	[STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
-	[STR_FEAT_DESC_0].s = "Volume control & mute",
-	[STR_OUTPUT_TERMINAL].s = "Output terminal",
-	[STR_AS_IF_ALT0].s = "AS Interface",
-	[STR_AS_IF_ALT1].s = "AS Interface",
+	[STR_USB_OUT_IT].s = "Playback Input terminal",
+	[STR_USB_OUT_IT_CH_NAMES].s = "Playback Channels",
+	[STR_IO_OUT_OT].s = "Playback Output terminal",
+	[STR_IO_IN_IT].s = "Capture Input terminal",
+	[STR_IO_IN_IT_CH_NAMES].s = "Capture Channels",
+	[STR_USB_IN_OT].s = "Capture Output terminal",
+	[STR_AS_OUT_IF_ALT0].s = "Playback Inactive",
+	[STR_AS_OUT_IF_ALT1].s = "Playback Active",
+	[STR_AS_IN_IF_ALT0].s = "Capture Inactive",
+	[STR_AS_IN_IF_ALT1].s = "Capture Active",
 	{ },
 };
 
@@ -243,216 +322,6 @@ static struct usb_gadget_strings *uac1_strings[] = {
  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
  */
 
-/*-------------------------------------------------------------------------*/
-struct f_audio_buf {
-	u8 *buf;
-	int actual;
-	struct list_head list;
-};
-
-static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
-{
-	struct f_audio_buf *copy_buf;
-
-	copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
-	if (!copy_buf)
-		return ERR_PTR(-ENOMEM);
-
-	copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
-	if (!copy_buf->buf) {
-		kfree(copy_buf);
-		return ERR_PTR(-ENOMEM);
-	}
-
-	return copy_buf;
-}
-
-static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
-{
-	kfree(audio_buf->buf);
-	kfree(audio_buf);
-}
-/*-------------------------------------------------------------------------*/
-
-struct f_audio {
-	struct gaudio			card;
-
-	/* endpoints handle full and/or high speeds */
-	struct usb_ep			*out_ep;
-
-	spinlock_t			lock;
-	struct f_audio_buf *copy_buf;
-	struct work_struct playback_work;
-	struct list_head play_queue;
-
-	/* Control Set command */
-	struct list_head cs;
-	u8 set_cmd;
-	struct usb_audio_control *set_con;
-};
-
-static inline struct f_audio *func_to_audio(struct usb_function *f)
-{
-	return container_of(f, struct f_audio, card.func);
-}
-
-/*-------------------------------------------------------------------------*/
-
-static void f_audio_playback_work(struct work_struct *data)
-{
-	struct f_audio *audio = container_of(data, struct f_audio,
-					playback_work);
-	struct f_audio_buf *play_buf;
-
-	spin_lock_irq(&audio->lock);
-	if (list_empty(&audio->play_queue)) {
-		spin_unlock_irq(&audio->lock);
-		return;
-	}
-	play_buf = list_first_entry(&audio->play_queue,
-			struct f_audio_buf, list);
-	list_del(&play_buf->list);
-	spin_unlock_irq(&audio->lock);
-
-	u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
-	f_audio_buffer_free(play_buf);
-}
-
-static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct f_audio *audio = req->context;
-	struct usb_composite_dev *cdev = audio->card.func.config->cdev;
-	struct f_audio_buf *copy_buf = audio->copy_buf;
-	struct f_uac1_opts *opts;
-	int audio_buf_size;
-	int err;
-
-	opts = container_of(audio->card.func.fi, struct f_uac1_opts,
-			    func_inst);
-	audio_buf_size = opts->audio_buf_size;
-
-	if (!copy_buf)
-		return -EINVAL;
-
-	/* Copy buffer is full, add it to the play_queue */
-	if (audio_buf_size - copy_buf->actual < req->actual) {
-		list_add_tail(&copy_buf->list, &audio->play_queue);
-		schedule_work(&audio->playback_work);
-		copy_buf = f_audio_buffer_alloc(audio_buf_size);
-		if (IS_ERR(copy_buf))
-			return -ENOMEM;
-	}
-
-	memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
-	copy_buf->actual += req->actual;
-	audio->copy_buf = copy_buf;
-
-	err = usb_ep_queue(ep, req, GFP_ATOMIC);
-	if (err)
-		ERROR(cdev, "%s queue req: %d\n", ep->name, err);
-
-	return 0;
-
-}
-
-static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct f_audio *audio = req->context;
-	int status = req->status;
-	u32 data = 0;
-	struct usb_ep *out_ep = audio->out_ep;
-
-	switch (status) {
-
-	case 0:				/* normal completion? */
-		if (ep == out_ep)
-			f_audio_out_ep_complete(ep, req);
-		else if (audio->set_con) {
-			memcpy(&data, req->buf, req->length);
-			audio->set_con->set(audio->set_con, audio->set_cmd,
-					le16_to_cpu(data));
-			audio->set_con = NULL;
-		}
-		break;
-	default:
-		break;
-	}
-}
-
-static int audio_set_intf_req(struct usb_function *f,
-		const struct usb_ctrlrequest *ctrl)
-{
-	struct f_audio		*audio = func_to_audio(f);
-	struct usb_composite_dev *cdev = f->config->cdev;
-	struct usb_request	*req = cdev->req;
-	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
-	u16			len = le16_to_cpu(ctrl->wLength);
-	u16			w_value = le16_to_cpu(ctrl->wValue);
-	u8			con_sel = (w_value >> 8) & 0xFF;
-	u8			cmd = (ctrl->bRequest & 0x0F);
-	struct usb_audio_control_selector *cs;
-	struct usb_audio_control *con;
-
-	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
-			ctrl->bRequest, w_value, len, id);
-
-	list_for_each_entry(cs, &audio->cs, list) {
-		if (cs->id == id) {
-			list_for_each_entry(con, &cs->control, list) {
-				if (con->type == con_sel) {
-					audio->set_con = con;
-					break;
-				}
-			}
-			break;
-		}
-	}
-
-	audio->set_cmd = cmd;
-	req->context = audio;
-	req->complete = f_audio_complete;
-
-	return len;
-}
-
-static int audio_get_intf_req(struct usb_function *f,
-		const struct usb_ctrlrequest *ctrl)
-{
-	struct f_audio		*audio = func_to_audio(f);
-	struct usb_composite_dev *cdev = f->config->cdev;
-	struct usb_request	*req = cdev->req;
-	int			value = -EOPNOTSUPP;
-	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
-	u16			len = le16_to_cpu(ctrl->wLength);
-	u16			w_value = le16_to_cpu(ctrl->wValue);
-	u8			con_sel = (w_value >> 8) & 0xFF;
-	u8			cmd = (ctrl->bRequest & 0x0F);
-	struct usb_audio_control_selector *cs;
-	struct usb_audio_control *con;
-
-	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
-			ctrl->bRequest, w_value, len, id);
-
-	list_for_each_entry(cs, &audio->cs, list) {
-		if (cs->id == id) {
-			list_for_each_entry(con, &cs->control, list) {
-				if (con->type == con_sel && con->get) {
-					value = con->get(con, cmd);
-					break;
-				}
-			}
-			break;
-		}
-	}
-
-	req->context = audio;
-	req->complete = f_audio_complete;
-	len = min_t(size_t, sizeof(value), len);
-	memcpy(req->buf, &value, len);
-
-	return len;
-}
-
 static int audio_set_endpoint_req(struct usb_function *f,
 		const struct usb_ctrlrequest *ctrl)
 {
@@ -531,14 +400,6 @@ f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 	 * activation uses set_alt().
 	 */
 	switch (ctrl->bRequestType) {
-	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
-		value = audio_set_intf_req(f, ctrl);
-		break;
-
-	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
-		value = audio_get_intf_req(f, ctrl);
-		break;
-
 	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 		value = audio_set_endpoint_req(f, ctrl);
 		break;
@@ -571,143 +432,158 @@ f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 
 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
-	struct f_audio		*audio = func_to_audio(f);
 	struct usb_composite_dev *cdev = f->config->cdev;
-	struct usb_ep *out_ep = audio->out_ep;
-	struct usb_request *req;
-	struct f_uac1_opts *opts;
-	int req_buf_size, req_count, audio_buf_size;
-	int i = 0, err = 0;
-
-	DBG(cdev, "intf %d, alt %d\n", intf, alt);
+	struct usb_gadget *gadget = cdev->gadget;
+	struct device *dev = &gadget->dev;
+	struct f_uac1 *uac1 = func_to_uac1(f);
+	int ret = 0;
+
+	/* No i/f has more than 2 alt settings */
+	if (alt > 1) {
+		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+		return -EINVAL;
+	}
 
-	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
-	req_buf_size = opts->req_buf_size;
-	req_count = opts->req_count;
-	audio_buf_size = opts->audio_buf_size;
-
-	if (intf == 1) {
-		if (alt == 1) {
-			err = config_ep_by_speed(cdev->gadget, f, out_ep);
-			if (err)
-				return err;
-
-			usb_ep_enable(out_ep);
-			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
-			if (IS_ERR(audio->copy_buf))
-				return -ENOMEM;
-
-			/*
-			 * allocate a bunch of read buffers
-			 * and queue them all at once.
-			 */
-			for (i = 0; i < req_count && err == 0; i++) {
-				req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
-				if (req) {
-					req->buf = kzalloc(req_buf_size,
-							GFP_ATOMIC);
-					if (req->buf) {
-						req->length = req_buf_size;
-						req->context = audio;
-						req->complete =
-							f_audio_complete;
-						err = usb_ep_queue(out_ep,
-							req, GFP_ATOMIC);
-						if (err)
-							ERROR(cdev,
-							"%s queue req: %d\n",
-							out_ep->name, err);
-					} else
-						err = -ENOMEM;
-				} else
-					err = -ENOMEM;
-			}
-
-		} else {
-			struct f_audio_buf *copy_buf = audio->copy_buf;
-			if (copy_buf) {
-				list_add_tail(&copy_buf->list,
-						&audio->play_queue);
-				schedule_work(&audio->playback_work);
-			}
+	if (intf == uac1->ac_intf) {
+		/* Control I/f has only 1 AltSetting - 0 */
+		if (alt) {
+			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+			return -EINVAL;
 		}
+		return 0;
 	}
 
-	return err;
+	if (intf == uac1->as_out_intf) {
+		uac1->as_out_alt = alt;
+
+		if (alt)
+			ret = u_audio_start_capture(&uac1->g_audio);
+		else
+			u_audio_stop_capture(&uac1->g_audio);
+	} else if (intf == uac1->as_in_intf) {
+		uac1->as_in_alt = alt;
+
+			if (alt)
+				ret = u_audio_start_playback(&uac1->g_audio);
+			else
+				u_audio_stop_playback(&uac1->g_audio);
+	} else {
+		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+		return -EINVAL;
+	}
+
+	return ret;
 }
 
-static void f_audio_disable(struct usb_function *f)
+static int f_audio_get_alt(struct usb_function *f, unsigned intf)
 {
-	return;
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_gadget *gadget = cdev->gadget;
+	struct device *dev = &gadget->dev;
+	struct f_uac1 *uac1 = func_to_uac1(f);
+
+	if (intf == uac1->ac_intf)
+		return uac1->ac_alt;
+	else if (intf == uac1->as_out_intf)
+		return uac1->as_out_alt;
+	else if (intf == uac1->as_in_intf)
+		return uac1->as_in_alt;
+	else
+		dev_err(dev, "%s:%d Invalid Interface %d!\n",
+			__func__, __LINE__, intf);
+
+	return -EINVAL;
 }
 
-/*-------------------------------------------------------------------------*/
 
-static void f_audio_build_desc(struct f_audio *audio)
+static void f_audio_disable(struct usb_function *f)
 {
-	struct gaudio *card = &audio->card;
-	u8 *sam_freq;
-	int rate;
+	struct f_uac1 *uac1 = func_to_uac1(f);
 
-	/* Set channel numbers */
-	input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
-	as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
+	uac1->as_out_alt = 0;
+	uac1->as_in_alt = 0;
 
-	/* Set sample rates */
-	rate = u_audio_get_playback_rate(card);
-	sam_freq = as_type_i_desc.tSamFreq[0];
-	memcpy(sam_freq, &rate, 3);
-
-	/* Todo: Set Sample bits and other parameters */
-
-	return;
+	u_audio_stop_capture(&uac1->g_audio);
 }
 
+/*-------------------------------------------------------------------------*/
+
 /* audio function driver setup/binding */
-static int
-f_audio_bind(struct usb_configuration *c, struct usb_function *f)
+static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 {
-	struct usb_composite_dev *cdev = c->cdev;
-	struct f_audio		*audio = func_to_audio(f);
-	struct usb_string	*us;
-	int			status;
-	struct usb_ep		*ep = NULL;
-	struct f_uac1_opts	*audio_opts;
+	struct usb_composite_dev	*cdev = c->cdev;
+	struct usb_gadget		*gadget = cdev->gadget;
+	struct f_uac1			*uac1 = func_to_uac1(f);
+	struct g_audio			*audio = func_to_g_audio(f);
+	struct f_uac1_opts		*audio_opts;
+	struct usb_ep			*ep = NULL;
+	struct usb_string		*us;
+	u8				*sam_freq;
+	int				rate;
+	int				status;
 
 	audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
-	audio->card.gadget = c->cdev->gadget;
-	/* set up ASLA audio devices */
-	if (!audio_opts->bound) {
-		status = gaudio_setup(&audio->card);
-		if (status < 0)
-			return status;
-		audio_opts->bound = true;
-	}
+
 	us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
 	if (IS_ERR(us))
 		return PTR_ERR(us);
 	ac_interface_desc.iInterface = us[STR_AC_IF].id;
-	input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
-	input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
-	feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
-	output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
-	as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
-	as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
+	usb_out_it_desc.iTerminal = us[STR_USB_OUT_IT].id;
+	usb_out_it_desc.iChannelNames = us[STR_USB_OUT_IT_CH_NAMES].id;
+	io_out_ot_desc.iTerminal = us[STR_IO_OUT_OT].id;
+	as_out_interface_alt_0_desc.iInterface = us[STR_AS_OUT_IF_ALT0].id;
+	as_out_interface_alt_1_desc.iInterface = us[STR_AS_OUT_IF_ALT1].id;
+	io_in_it_desc.iTerminal = us[STR_IO_IN_IT].id;
+	io_in_it_desc.iChannelNames = us[STR_IO_IN_IT_CH_NAMES].id;
+	usb_in_ot_desc.iTerminal = us[STR_USB_IN_OT].id;
+	as_in_interface_alt_0_desc.iInterface = us[STR_AS_IN_IF_ALT0].id;
+	as_in_interface_alt_1_desc.iInterface = us[STR_AS_IN_IF_ALT1].id;
 
+	/* Set channel numbers */
+	usb_out_it_desc.bNrChannels = num_channels(audio_opts->c_chmask);
+	usb_out_it_desc.wChannelConfig = cpu_to_le16(audio_opts->c_chmask);
+	as_out_type_i_desc.bNrChannels = num_channels(audio_opts->c_chmask);
+	as_out_type_i_desc.bSubframeSize = audio_opts->c_ssize;
+	as_out_type_i_desc.bBitResolution = audio_opts->c_ssize * 8;
+	io_in_it_desc.bNrChannels = num_channels(audio_opts->p_chmask);
+	io_in_it_desc.wChannelConfig = cpu_to_le16(audio_opts->p_chmask);
+	as_in_type_i_desc.bNrChannels = num_channels(audio_opts->p_chmask);
+	as_in_type_i_desc.bSubframeSize = audio_opts->p_ssize;
+	as_in_type_i_desc.bBitResolution = audio_opts->p_ssize * 8;
 
-	f_audio_build_desc(audio);
+	/* Set sample rates */
+	rate = audio_opts->c_srate;
+	sam_freq = as_out_type_i_desc.tSamFreq[0];
+	memcpy(sam_freq, &rate, 3);
+	rate = audio_opts->p_srate;
+	sam_freq = as_in_type_i_desc.tSamFreq[0];
+	memcpy(sam_freq, &rate, 3);
 
 	/* allocate instance-specific interface IDs, and patch descriptors */
 	status = usb_interface_id(c, f);
 	if (status < 0)
 		goto fail;
 	ac_interface_desc.bInterfaceNumber = status;
+	uac1->ac_intf = status;
+	uac1->ac_alt = 0;
 
 	status = usb_interface_id(c, f);
 	if (status < 0)
 		goto fail;
-	as_interface_alt_0_desc.bInterfaceNumber = status;
-	as_interface_alt_1_desc.bInterfaceNumber = status;
+	as_out_interface_alt_0_desc.bInterfaceNumber = status;
+	as_out_interface_alt_1_desc.bInterfaceNumber = status;
+	uac1->as_out_intf = status;
+	uac1->as_out_alt = 0;
+
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	as_in_interface_alt_0_desc.bInterfaceNumber = status;
+	as_in_interface_alt_1_desc.bInterfaceNumber = status;
+	uac1->as_in_intf = status;
+	uac1->as_in_alt = 0;
+
+	audio->gadget = gadget;
 
 	status = -ENODEV;
 
@@ -718,52 +594,42 @@ f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 	audio->out_ep = ep;
 	audio->out_ep->desc = &as_out_ep_desc;
 
-	status = -ENOMEM;
+	ep = usb_ep_autoconfig(cdev->gadget, &as_in_ep_desc);
+	if (!ep)
+		goto fail;
+	audio->in_ep = ep;
+	audio->in_ep->desc = &as_in_ep_desc;
 
 	/* copy descriptors, and track endpoint copies */
 	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
 					NULL);
 	if (status)
 		goto fail;
+
+	audio->out_ep_maxpsize = as_out_ep_desc.wMaxPacketSize;
+	audio->in_ep_maxpsize = as_in_ep_desc.wMaxPacketSize;
+	audio->params.c_chmask = audio_opts->c_chmask;
+	audio->params.c_srate = audio_opts->c_srate;
+	audio->params.c_ssize = audio_opts->c_ssize;
+	audio->params.p_chmask = audio_opts->p_chmask;
+	audio->params.p_srate = audio_opts->p_srate;
+	audio->params.p_ssize = audio_opts->p_ssize;
+	audio->params.req_number = audio_opts->req_number;
+
+	status = g_audio_setup(audio, "UAC1_PCM", "UAC1_Gadget");
+	if (status)
+		goto err_card_register;
+
 	return 0;
 
+err_card_register:
+	usb_free_all_descriptors(f);
 fail:
-	gaudio_cleanup(&audio->card);
 	return status;
 }
 
 /*-------------------------------------------------------------------------*/
 
-static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
-{
-	con->data[cmd] = value;
-
-	return 0;
-}
-
-static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
-{
-	return con->data[cmd];
-}
-
-/* Todo: add more control selecotor dynamically */
-static int control_selector_init(struct f_audio *audio)
-{
-	INIT_LIST_HEAD(&audio->cs);
-	list_add(&feature_unit.list, &audio->cs);
-
-	INIT_LIST_HEAD(&feature_unit.control);
-	list_add(&mute_control.list, &feature_unit.control);
-	list_add(&volume_control.list, &feature_unit.control);
-
-	volume_control.data[UAC__CUR] = 0xffc0;
-	volume_control.data[UAC__MIN] = 0xe3a0;
-	volume_control.data[UAC__MAX] = 0xfff0;
-	volume_control.data[UAC__RES] = 0x0030;
-
-	return 0;
-}
-
 static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
 {
 	return container_of(to_config_group(item), struct f_uac1_opts,
@@ -781,9 +647,10 @@ static struct configfs_item_operations f_uac1_item_ops = {
 	.release	= f_uac1_attr_release,
 };
 
-#define UAC1_INT_ATTRIBUTE(name)					\
-static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
-					 char *page)			\
+#define UAC1_ATTRIBUTE(name)						\
+static ssize_t f_uac1_opts_##name##_show(				\
+					  struct config_item *item,	\
+					  char *page)			\
 {									\
 	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
 	int result;							\
@@ -795,7 +662,8 @@ static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
 	return result;							\
 }									\
 									\
-static ssize_t f_uac1_opts_##name##_store(struct config_item *item,		\
+static ssize_t f_uac1_opts_##name##_store(				\
+					  struct config_item *item,	\
 					  const char *page, size_t len)	\
 {									\
 	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
@@ -822,64 +690,22 @@ end:									\
 									\
 CONFIGFS_ATTR(f_uac1_opts_, name)
 
-UAC1_INT_ATTRIBUTE(req_buf_size);
-UAC1_INT_ATTRIBUTE(req_count);
-UAC1_INT_ATTRIBUTE(audio_buf_size);
-
-#define UAC1_STR_ATTRIBUTE(name)					\
-static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
-					 char *page)			\
-{									\
-	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
-	int result;							\
-									\
-	mutex_lock(&opts->lock);					\
-	result = sprintf(page, "%s\n", opts->name);			\
-	mutex_unlock(&opts->lock);					\
-									\
-	return result;							\
-}									\
-									\
-static ssize_t f_uac1_opts_##name##_store(struct config_item *item,	\
-					  const char *page, size_t len)	\
-{									\
-	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
-	int ret = -EBUSY;						\
-	char *tmp;							\
-									\
-	mutex_lock(&opts->lock);					\
-	if (opts->refcnt)						\
-		goto end;						\
-									\
-	tmp = kstrndup(page, len, GFP_KERNEL);				\
-	if (tmp) {							\
-		ret = -ENOMEM;						\
-		goto end;						\
-	}								\
-	if (opts->name##_alloc)						\
-		kfree(opts->name);					\
-	opts->name##_alloc = true;					\
-	opts->name = tmp;						\
-	ret = len;							\
-									\
-end:									\
-	mutex_unlock(&opts->lock);					\
-	return ret;							\
-}									\
-									\
-CONFIGFS_ATTR(f_uac1_opts_, name)
-
-UAC1_STR_ATTRIBUTE(fn_play);
-UAC1_STR_ATTRIBUTE(fn_cap);
-UAC1_STR_ATTRIBUTE(fn_cntl);
+UAC1_ATTRIBUTE(c_chmask);
+UAC1_ATTRIBUTE(c_srate);
+UAC1_ATTRIBUTE(c_ssize);
+UAC1_ATTRIBUTE(p_chmask);
+UAC1_ATTRIBUTE(p_srate);
+UAC1_ATTRIBUTE(p_ssize);
+UAC1_ATTRIBUTE(req_number);
 
 static struct configfs_attribute *f_uac1_attrs[] = {
-	&f_uac1_opts_attr_req_buf_size,
-	&f_uac1_opts_attr_req_count,
-	&f_uac1_opts_attr_audio_buf_size,
-	&f_uac1_opts_attr_fn_play,
-	&f_uac1_opts_attr_fn_cap,
-	&f_uac1_opts_attr_fn_cntl,
+	&f_uac1_opts_attr_c_chmask,
+	&f_uac1_opts_attr_c_srate,
+	&f_uac1_opts_attr_c_ssize,
+	&f_uac1_opts_attr_p_chmask,
+	&f_uac1_opts_attr_p_srate,
+	&f_uac1_opts_attr_p_ssize,
+	&f_uac1_opts_attr_req_number,
 	NULL,
 };
 
@@ -894,12 +720,6 @@ static void f_audio_free_inst(struct usb_function_instance *f)
 	struct f_uac1_opts *opts;
 
 	opts = container_of(f, struct f_uac1_opts, func_inst);
-	if (opts->fn_play_alloc)
-		kfree(opts->fn_play);
-	if (opts->fn_cap_alloc)
-		kfree(opts->fn_cap);
-	if (opts->fn_cntl_alloc)
-		kfree(opts->fn_cntl);
 	kfree(opts);
 }
 
@@ -917,21 +737,22 @@ static struct usb_function_instance *f_audio_alloc_inst(void)
 	config_group_init_type_name(&opts->func_inst.group, "",
 				    &f_uac1_func_type);
 
-	opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
-	opts->req_count = UAC1_REQ_COUNT;
-	opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
-	opts->fn_play = FILE_PCM_PLAYBACK;
-	opts->fn_cap = FILE_PCM_CAPTURE;
-	opts->fn_cntl = FILE_CONTROL;
+	opts->c_chmask = UAC1_DEF_CCHMASK;
+	opts->c_srate = UAC1_DEF_CSRATE;
+	opts->c_ssize = UAC1_DEF_CSSIZE;
+	opts->p_chmask = UAC1_DEF_PCHMASK;
+	opts->p_srate = UAC1_DEF_PSRATE;
+	opts->p_ssize = UAC1_DEF_PSSIZE;
+	opts->req_number = UAC1_DEF_REQ_NUM;
 	return &opts->func_inst;
 }
 
 static void f_audio_free(struct usb_function *f)
 {
-	struct f_audio *audio = func_to_audio(f);
+	struct g_audio *audio;
 	struct f_uac1_opts *opts;
 
-	gaudio_cleanup(&audio->card);
+	audio = func_to_g_audio(f);
 	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 	kfree(audio);
 	mutex_lock(&opts->lock);
@@ -941,42 +762,41 @@ static void f_audio_free(struct usb_function *f)
 
 static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 {
+	struct g_audio *audio = func_to_g_audio(f);
+
+	g_audio_cleanup(audio);
 	usb_free_all_descriptors(f);
+
+	audio->gadget = NULL;
 }
 
 static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 {
-	struct f_audio *audio;
+	struct f_uac1 *uac1;
 	struct f_uac1_opts *opts;
 
 	/* allocate and initialize one new instance */
-	audio = kzalloc(sizeof(*audio), GFP_KERNEL);
-	if (!audio)
+	uac1 = kzalloc(sizeof(*uac1), GFP_KERNEL);
+	if (!uac1)
 		return ERR_PTR(-ENOMEM);
 
-	audio->card.func.name = "g_audio";
-
 	opts = container_of(fi, struct f_uac1_opts, func_inst);
 	mutex_lock(&opts->lock);
 	++opts->refcnt;
 	mutex_unlock(&opts->lock);
-	INIT_LIST_HEAD(&audio->play_queue);
-	spin_lock_init(&audio->lock);
-
-	audio->card.func.bind = f_audio_bind;
-	audio->card.func.unbind = f_audio_unbind;
-	audio->card.func.set_alt = f_audio_set_alt;
-	audio->card.func.setup = f_audio_setup;
-	audio->card.func.disable = f_audio_disable;
-	audio->card.func.free_func = f_audio_free;
-
-	control_selector_init(audio);
 
-	INIT_WORK(&audio->playback_work, f_audio_playback_work);
+	uac1->g_audio.func.name = "uac1_func";
+	uac1->g_audio.func.bind = f_audio_bind;
+	uac1->g_audio.func.unbind = f_audio_unbind;
+	uac1->g_audio.func.set_alt = f_audio_set_alt;
+	uac1->g_audio.func.get_alt = f_audio_get_alt;
+	uac1->g_audio.func.setup = f_audio_setup;
+	uac1->g_audio.func.disable = f_audio_disable;
+	uac1->g_audio.func.free_func = f_audio_free;
 
-	return &audio->card.func;
+	return &uac1->g_audio.func;
 }
 
 DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
 MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Bryan Wu");
+MODULE_AUTHOR("Ruslan Bilovol");
diff --git a/drivers/usb/gadget/function/f_uac1_legacy.c b/drivers/usb/gadget/function/f_uac1_legacy.c
new file mode 100644
index 000000000000..5d229e72912e
--- /dev/null
+++ b/drivers/usb/gadget/function/f_uac1_legacy.c
@@ -0,0 +1,1021 @@
+/*
+ * f_audio.c -- USB Audio class function driver
+  *
+ * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
+ * Copyright (C) 2008 Analog Devices, Inc
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/atomic.h>
+
+#include "u_uac1_legacy.h"
+
+static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
+static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
+
+/*
+ * DESCRIPTORS ... most are static, but strings and full
+ * configuration descriptors are built on demand.
+ */
+
+/*
+ * We have two interfaces- AudioControl and AudioStreaming
+ * TODO: only supcard playback currently
+ */
+#define F_AUDIO_AC_INTERFACE	0
+#define F_AUDIO_AS_INTERFACE	1
+#define F_AUDIO_NUM_INTERFACES	1
+
+/* B.3.1  Standard AC Interface Descriptor */
+static struct usb_interface_descriptor ac_interface_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOCONTROL,
+};
+
+/*
+ * The number of AudioStreaming and MIDIStreaming interfaces
+ * in the Audio Interface Collection
+ */
+DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
+
+#define UAC_DT_AC_HEADER_LENGTH	UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
+/* 1 input terminal, 1 output terminal and 1 feature unit */
+#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
+	+ UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
+/* B.3.2  Class-Specific AC Interface Descriptor */
+static struct uac1_ac_header_descriptor_1 ac_header_desc = {
+	.bLength =		UAC_DT_AC_HEADER_LENGTH,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_HEADER,
+	.bcdADC =		__constant_cpu_to_le16(0x0100),
+	.wTotalLength =		__constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
+	.bInCollection =	F_AUDIO_NUM_INTERFACES,
+	.baInterfaceNr = {
+	/* Interface number of the first AudioStream interface */
+		[0] =		1,
+	}
+};
+
+#define INPUT_TERMINAL_ID	1
+static struct uac_input_terminal_descriptor input_terminal_desc = {
+	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
+	.bTerminalID =		INPUT_TERMINAL_ID,
+	.wTerminalType =	UAC_TERMINAL_STREAMING,
+	.bAssocTerminal =	0,
+	.wChannelConfig =	0x3,
+};
+
+DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
+
+#define FEATURE_UNIT_ID		2
+static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
+	.bLength		= UAC_DT_FEATURE_UNIT_SIZE(0),
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype	= UAC_FEATURE_UNIT,
+	.bUnitID		= FEATURE_UNIT_ID,
+	.bSourceID		= INPUT_TERMINAL_ID,
+	.bControlSize		= 2,
+	.bmaControls[0]		= (UAC_FU_MUTE | UAC_FU_VOLUME),
+};
+
+static struct usb_audio_control mute_control = {
+	.list = LIST_HEAD_INIT(mute_control.list),
+	.name = "Mute Control",
+	.type = UAC_FU_MUTE,
+	/* Todo: add real Mute control code */
+	.set = generic_set_cmd,
+	.get = generic_get_cmd,
+};
+
+static struct usb_audio_control volume_control = {
+	.list = LIST_HEAD_INIT(volume_control.list),
+	.name = "Volume Control",
+	.type = UAC_FU_VOLUME,
+	/* Todo: add real Volume control code */
+	.set = generic_set_cmd,
+	.get = generic_get_cmd,
+};
+
+static struct usb_audio_control_selector feature_unit = {
+	.list = LIST_HEAD_INIT(feature_unit.list),
+	.id = FEATURE_UNIT_ID,
+	.name = "Mute & Volume Control",
+	.type = UAC_FEATURE_UNIT,
+	.desc = (struct usb_descriptor_header *)&feature_unit_desc,
+};
+
+#define OUTPUT_TERMINAL_ID	3
+static struct uac1_output_terminal_descriptor output_terminal_desc = {
+	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
+	.bDescriptorType	= USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
+	.bTerminalID		= OUTPUT_TERMINAL_ID,
+	.wTerminalType		= UAC_OUTPUT_TERMINAL_SPEAKER,
+	.bAssocTerminal		= FEATURE_UNIT_ID,
+	.bSourceID		= FEATURE_UNIT_ID,
+};
+
+/* B.4.1  Standard AS Interface Descriptor */
+static struct usb_interface_descriptor as_interface_alt_0_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
+};
+
+static struct usb_interface_descriptor as_interface_alt_1_desc = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+	.bAlternateSetting =	1,
+	.bNumEndpoints =	1,
+	.bInterfaceClass =	USB_CLASS_AUDIO,
+	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
+};
+
+/* B.4.2  Class-Specific AS Interface Descriptor */
+static struct uac1_as_header_descriptor as_header_desc = {
+	.bLength =		UAC_DT_AS_HEADER_SIZE,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_AS_GENERAL,
+	.bTerminalLink =	INPUT_TERMINAL_ID,
+	.bDelay =		1,
+	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
+};
+
+DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
+
+static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
+	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
+	.bFormatType =		UAC_FORMAT_TYPE_I,
+	.bSubframeSize =	2,
+	.bBitResolution =	16,
+	.bSamFreqType =		1,
+};
+
+/* Standard ISO OUT Endpoint Descriptor */
+static struct usb_endpoint_descriptor as_out_ep_desc  = {
+	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_SYNC_ADAPTIVE
+				| USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
+	.bInterval =		4,
+};
+
+/* Class-specific AS ISO OUT Endpoint Descriptor */
+static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
+	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
+	.bDescriptorType =	USB_DT_CS_ENDPOINT,
+	.bDescriptorSubtype =	UAC_EP_GENERAL,
+	.bmAttributes = 	1,
+	.bLockDelayUnits =	1,
+	.wLockDelay =		__constant_cpu_to_le16(1),
+};
+
+static struct usb_descriptor_header *f_audio_desc[] = {
+	(struct usb_descriptor_header *)&ac_interface_desc,
+	(struct usb_descriptor_header *)&ac_header_desc,
+
+	(struct usb_descriptor_header *)&input_terminal_desc,
+	(struct usb_descriptor_header *)&output_terminal_desc,
+	(struct usb_descriptor_header *)&feature_unit_desc,
+
+	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
+	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
+	(struct usb_descriptor_header *)&as_header_desc,
+
+	(struct usb_descriptor_header *)&as_type_i_desc,
+
+	(struct usb_descriptor_header *)&as_out_ep_desc,
+	(struct usb_descriptor_header *)&as_iso_out_desc,
+	NULL,
+};
+
+enum {
+	STR_AC_IF,
+	STR_INPUT_TERMINAL,
+	STR_INPUT_TERMINAL_CH_NAMES,
+	STR_FEAT_DESC_0,
+	STR_OUTPUT_TERMINAL,
+	STR_AS_IF_ALT0,
+	STR_AS_IF_ALT1,
+};
+
+static struct usb_string strings_uac1[] = {
+	[STR_AC_IF].s = "AC Interface",
+	[STR_INPUT_TERMINAL].s = "Input terminal",
+	[STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
+	[STR_FEAT_DESC_0].s = "Volume control & mute",
+	[STR_OUTPUT_TERMINAL].s = "Output terminal",
+	[STR_AS_IF_ALT0].s = "AS Interface",
+	[STR_AS_IF_ALT1].s = "AS Interface",
+	{ },
+};
+
+static struct usb_gadget_strings str_uac1 = {
+	.language = 0x0409,	/* en-us */
+	.strings = strings_uac1,
+};
+
+static struct usb_gadget_strings *uac1_strings[] = {
+	&str_uac1,
+	NULL,
+};
+
+/*
+ * This function is an ALSA sound card following USB Audio Class Spec 1.0.
+ */
+
+/*-------------------------------------------------------------------------*/
+struct f_audio_buf {
+	u8 *buf;
+	int actual;
+	struct list_head list;
+};
+
+static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
+{
+	struct f_audio_buf *copy_buf;
+
+	copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
+	if (!copy_buf)
+		return ERR_PTR(-ENOMEM);
+
+	copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
+	if (!copy_buf->buf) {
+		kfree(copy_buf);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return copy_buf;
+}
+
+static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
+{
+	kfree(audio_buf->buf);
+	kfree(audio_buf);
+}
+/*-------------------------------------------------------------------------*/
+
+struct f_audio {
+	struct gaudio			card;
+
+	u8 ac_intf, ac_alt;
+	u8 as_intf, as_alt;
+
+	/* endpoints handle full and/or high speeds */
+	struct usb_ep			*out_ep;
+
+	spinlock_t			lock;
+	struct f_audio_buf *copy_buf;
+	struct work_struct playback_work;
+	struct list_head play_queue;
+
+	/* Control Set command */
+	struct list_head cs;
+	u8 set_cmd;
+	struct usb_audio_control *set_con;
+};
+
+static inline struct f_audio *func_to_audio(struct usb_function *f)
+{
+	return container_of(f, struct f_audio, card.func);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void f_audio_playback_work(struct work_struct *data)
+{
+	struct f_audio *audio = container_of(data, struct f_audio,
+					playback_work);
+	struct f_audio_buf *play_buf;
+
+	spin_lock_irq(&audio->lock);
+	if (list_empty(&audio->play_queue)) {
+		spin_unlock_irq(&audio->lock);
+		return;
+	}
+	play_buf = list_first_entry(&audio->play_queue,
+			struct f_audio_buf, list);
+	list_del(&play_buf->list);
+	spin_unlock_irq(&audio->lock);
+
+	u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
+	f_audio_buffer_free(play_buf);
+}
+
+static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct f_audio *audio = req->context;
+	struct usb_composite_dev *cdev = audio->card.func.config->cdev;
+	struct f_audio_buf *copy_buf = audio->copy_buf;
+	struct f_uac1_legacy_opts *opts;
+	int audio_buf_size;
+	int err;
+
+	opts = container_of(audio->card.func.fi, struct f_uac1_legacy_opts,
+			    func_inst);
+	audio_buf_size = opts->audio_buf_size;
+
+	if (!copy_buf)
+		return -EINVAL;
+
+	/* Copy buffer is full, add it to the play_queue */
+	if (audio_buf_size - copy_buf->actual < req->actual) {
+		list_add_tail(&copy_buf->list, &audio->play_queue);
+		schedule_work(&audio->playback_work);
+		copy_buf = f_audio_buffer_alloc(audio_buf_size);
+		if (IS_ERR(copy_buf))
+			return -ENOMEM;
+	}
+
+	memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
+	copy_buf->actual += req->actual;
+	audio->copy_buf = copy_buf;
+
+	err = usb_ep_queue(ep, req, GFP_ATOMIC);
+	if (err)
+		ERROR(cdev, "%s queue req: %d\n", ep->name, err);
+
+	return 0;
+
+}
+
+static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct f_audio *audio = req->context;
+	int status = req->status;
+	u32 data = 0;
+	struct usb_ep *out_ep = audio->out_ep;
+
+	switch (status) {
+
+	case 0:				/* normal completion? */
+		if (ep == out_ep)
+			f_audio_out_ep_complete(ep, req);
+		else if (audio->set_con) {
+			memcpy(&data, req->buf, req->length);
+			audio->set_con->set(audio->set_con, audio->set_cmd,
+					le16_to_cpu(data));
+			audio->set_con = NULL;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static int audio_set_intf_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct f_audio		*audio = func_to_audio(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request	*req = cdev->req;
+	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
+	u16			len = le16_to_cpu(ctrl->wLength);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u8			con_sel = (w_value >> 8) & 0xFF;
+	u8			cmd = (ctrl->bRequest & 0x0F);
+	struct usb_audio_control_selector *cs;
+	struct usb_audio_control *con;
+
+	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
+			ctrl->bRequest, w_value, len, id);
+
+	list_for_each_entry(cs, &audio->cs, list) {
+		if (cs->id == id) {
+			list_for_each_entry(con, &cs->control, list) {
+				if (con->type == con_sel) {
+					audio->set_con = con;
+					break;
+				}
+			}
+			break;
+		}
+	}
+
+	audio->set_cmd = cmd;
+	req->context = audio;
+	req->complete = f_audio_complete;
+
+	return len;
+}
+
+static int audio_get_intf_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct f_audio		*audio = func_to_audio(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request	*req = cdev->req;
+	int			value = -EOPNOTSUPP;
+	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
+	u16			len = le16_to_cpu(ctrl->wLength);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u8			con_sel = (w_value >> 8) & 0xFF;
+	u8			cmd = (ctrl->bRequest & 0x0F);
+	struct usb_audio_control_selector *cs;
+	struct usb_audio_control *con;
+
+	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
+			ctrl->bRequest, w_value, len, id);
+
+	list_for_each_entry(cs, &audio->cs, list) {
+		if (cs->id == id) {
+			list_for_each_entry(con, &cs->control, list) {
+				if (con->type == con_sel && con->get) {
+					value = con->get(con, cmd);
+					break;
+				}
+			}
+			break;
+		}
+	}
+
+	req->context = audio;
+	req->complete = f_audio_complete;
+	len = min_t(size_t, sizeof(value), len);
+	memcpy(req->buf, &value, len);
+
+	return len;
+}
+
+static int audio_set_endpoint_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_composite_dev *cdev = f->config->cdev;
+	int			value = -EOPNOTSUPP;
+	u16			ep = le16_to_cpu(ctrl->wIndex);
+	u16			len = le16_to_cpu(ctrl->wLength);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+
+	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
+			ctrl->bRequest, w_value, len, ep);
+
+	switch (ctrl->bRequest) {
+	case UAC_SET_CUR:
+		value = len;
+		break;
+
+	case UAC_SET_MIN:
+		break;
+
+	case UAC_SET_MAX:
+		break;
+
+	case UAC_SET_RES:
+		break;
+
+	case UAC_SET_MEM:
+		break;
+
+	default:
+		break;
+	}
+
+	return value;
+}
+
+static int audio_get_endpoint_req(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_composite_dev *cdev = f->config->cdev;
+	int value = -EOPNOTSUPP;
+	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
+	u16 len = le16_to_cpu(ctrl->wLength);
+	u16 w_value = le16_to_cpu(ctrl->wValue);
+
+	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
+			ctrl->bRequest, w_value, len, ep);
+
+	switch (ctrl->bRequest) {
+	case UAC_GET_CUR:
+	case UAC_GET_MIN:
+	case UAC_GET_MAX:
+	case UAC_GET_RES:
+		value = len;
+		break;
+	case UAC_GET_MEM:
+		break;
+	default:
+		break;
+	}
+
+	return value;
+}
+
+static int
+f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_request	*req = cdev->req;
+	int			value = -EOPNOTSUPP;
+	u16			w_index = le16_to_cpu(ctrl->wIndex);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u16			w_length = le16_to_cpu(ctrl->wLength);
+
+	/* composite driver infrastructure handles everything; interface
+	 * activation uses set_alt().
+	 */
+	switch (ctrl->bRequestType) {
+	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
+		value = audio_set_intf_req(f, ctrl);
+		break;
+
+	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
+		value = audio_get_intf_req(f, ctrl);
+		break;
+
+	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
+		value = audio_set_endpoint_req(f, ctrl);
+		break;
+
+	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
+		value = audio_get_endpoint_req(f, ctrl);
+		break;
+
+	default:
+		ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			w_value, w_index, w_length);
+	}
+
+	/* respond with data transfer or status phase? */
+	if (value >= 0) {
+		DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			w_value, w_index, w_length);
+		req->zero = 0;
+		req->length = value;
+		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
+		if (value < 0)
+			ERROR(cdev, "audio response on err %d\n", value);
+	}
+
+	/* device either stalls (value < 0) or reports success */
+	return value;
+}
+
+static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+	struct f_audio		*audio = func_to_audio(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+	struct usb_ep *out_ep = audio->out_ep;
+	struct usb_request *req;
+	struct f_uac1_legacy_opts *opts;
+	int req_buf_size, req_count, audio_buf_size;
+	int i = 0, err = 0;
+
+	DBG(cdev, "intf %d, alt %d\n", intf, alt);
+
+	opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
+	req_buf_size = opts->req_buf_size;
+	req_count = opts->req_count;
+	audio_buf_size = opts->audio_buf_size;
+
+	/* No i/f has more than 2 alt settings */
+	if (alt > 1) {
+		ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
+		return -EINVAL;
+	}
+
+	if (intf == audio->ac_intf) {
+		/* Control I/f has only 1 AltSetting - 0 */
+		if (alt) {
+			ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
+			return -EINVAL;
+		}
+		return 0;
+	} else if (intf == audio->as_intf) {
+		if (alt == 1) {
+			err = config_ep_by_speed(cdev->gadget, f, out_ep);
+			if (err)
+				return err;
+
+			usb_ep_enable(out_ep);
+			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
+			if (IS_ERR(audio->copy_buf))
+				return -ENOMEM;
+
+			/*
+			 * allocate a bunch of read buffers
+			 * and queue them all at once.
+			 */
+			for (i = 0; i < req_count && err == 0; i++) {
+				req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
+				if (req) {
+					req->buf = kzalloc(req_buf_size,
+							GFP_ATOMIC);
+					if (req->buf) {
+						req->length = req_buf_size;
+						req->context = audio;
+						req->complete =
+							f_audio_complete;
+						err = usb_ep_queue(out_ep,
+							req, GFP_ATOMIC);
+						if (err)
+							ERROR(cdev,
+							"%s queue req: %d\n",
+							out_ep->name, err);
+					} else
+						err = -ENOMEM;
+				} else
+					err = -ENOMEM;
+			}
+
+		} else {
+			struct f_audio_buf *copy_buf = audio->copy_buf;
+			if (copy_buf) {
+				list_add_tail(&copy_buf->list,
+						&audio->play_queue);
+				schedule_work(&audio->playback_work);
+			}
+		}
+		audio->as_alt = alt;
+	}
+
+	return err;
+}
+
+static int f_audio_get_alt(struct usb_function *f, unsigned intf)
+{
+	struct f_audio		*audio = func_to_audio(f);
+	struct usb_composite_dev *cdev = f->config->cdev;
+
+	if (intf == audio->ac_intf)
+		return audio->ac_alt;
+	else if (intf == audio->as_intf)
+		return audio->as_alt;
+	else
+		ERROR(cdev, "%s:%d Invalid Interface %d!\n",
+		      __func__, __LINE__, intf);
+
+	return -EINVAL;
+}
+
+static void f_audio_disable(struct usb_function *f)
+{
+	return;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void f_audio_build_desc(struct f_audio *audio)
+{
+	struct gaudio *card = &audio->card;
+	u8 *sam_freq;
+	int rate;
+
+	/* Set channel numbers */
+	input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
+	as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
+
+	/* Set sample rates */
+	rate = u_audio_get_playback_rate(card);
+	sam_freq = as_type_i_desc.tSamFreq[0];
+	memcpy(sam_freq, &rate, 3);
+
+	/* Todo: Set Sample bits and other parameters */
+
+	return;
+}
+
+/* audio function driver setup/binding */
+static int
+f_audio_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct f_audio		*audio = func_to_audio(f);
+	struct usb_string	*us;
+	int			status;
+	struct usb_ep		*ep = NULL;
+	struct f_uac1_legacy_opts	*audio_opts;
+
+	audio_opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
+	audio->card.gadget = c->cdev->gadget;
+	/* set up ASLA audio devices */
+	if (!audio_opts->bound) {
+		status = gaudio_setup(&audio->card);
+		if (status < 0)
+			return status;
+		audio_opts->bound = true;
+	}
+	us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+	ac_interface_desc.iInterface = us[STR_AC_IF].id;
+	input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
+	input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
+	feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
+	output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
+	as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
+	as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
+
+
+	f_audio_build_desc(audio);
+
+	/* allocate instance-specific interface IDs, and patch descriptors */
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	ac_interface_desc.bInterfaceNumber = status;
+	audio->ac_intf = status;
+	audio->ac_alt = 0;
+
+	status = usb_interface_id(c, f);
+	if (status < 0)
+		goto fail;
+	as_interface_alt_0_desc.bInterfaceNumber = status;
+	as_interface_alt_1_desc.bInterfaceNumber = status;
+	audio->as_intf = status;
+	audio->as_alt = 0;
+
+	status = -ENODEV;
+
+	/* allocate instance-specific endpoints */
+	ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
+	if (!ep)
+		goto fail;
+	audio->out_ep = ep;
+	audio->out_ep->desc = &as_out_ep_desc;
+
+	status = -ENOMEM;
+
+	/* copy descriptors, and track endpoint copies */
+	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
+					NULL);
+	if (status)
+		goto fail;
+	return 0;
+
+fail:
+	gaudio_cleanup(&audio->card);
+	return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
+{
+	con->data[cmd] = value;
+
+	return 0;
+}
+
+static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
+{
+	return con->data[cmd];
+}
+
+/* Todo: add more control selecotor dynamically */
+static int control_selector_init(struct f_audio *audio)
+{
+	INIT_LIST_HEAD(&audio->cs);
+	list_add(&feature_unit.list, &audio->cs);
+
+	INIT_LIST_HEAD(&feature_unit.control);
+	list_add(&mute_control.list, &feature_unit.control);
+	list_add(&volume_control.list, &feature_unit.control);
+
+	volume_control.data[UAC__CUR] = 0xffc0;
+	volume_control.data[UAC__MIN] = 0xe3a0;
+	volume_control.data[UAC__MAX] = 0xfff0;
+	volume_control.data[UAC__RES] = 0x0030;
+
+	return 0;
+}
+
+static inline
+struct f_uac1_legacy_opts *to_f_uac1_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_uac1_legacy_opts,
+			    func_inst.group);
+}
+
+static void f_uac1_attr_release(struct config_item *item)
+{
+	struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);
+
+	usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations f_uac1_item_ops = {
+	.release	= f_uac1_attr_release,
+};
+
+#define UAC1_INT_ATTRIBUTE(name)					\
+static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
+					 char *page)			\
+{									\
+	struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);		\
+	int result;							\
+									\
+	mutex_lock(&opts->lock);					\
+	result = sprintf(page, "%u\n", opts->name);			\
+	mutex_unlock(&opts->lock);					\
+									\
+	return result;							\
+}									\
+									\
+static ssize_t f_uac1_opts_##name##_store(struct config_item *item,		\
+					  const char *page, size_t len)	\
+{									\
+	struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);		\
+	int ret;							\
+	u32 num;							\
+									\
+	mutex_lock(&opts->lock);					\
+	if (opts->refcnt) {						\
+		ret = -EBUSY;						\
+		goto end;						\
+	}								\
+									\
+	ret = kstrtou32(page, 0, &num);					\
+	if (ret)							\
+		goto end;						\
+									\
+	opts->name = num;						\
+	ret = len;							\
+									\
+end:									\
+	mutex_unlock(&opts->lock);					\
+	return ret;							\
+}									\
+									\
+CONFIGFS_ATTR(f_uac1_opts_, name)
+
+UAC1_INT_ATTRIBUTE(req_buf_size);
+UAC1_INT_ATTRIBUTE(req_count);
+UAC1_INT_ATTRIBUTE(audio_buf_size);
+
+#define UAC1_STR_ATTRIBUTE(name)					\
+static ssize_t f_uac1_opts_##name##_show(struct config_item *item,	\
+					 char *page)			\
+{									\
+	struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);		\
+	int result;							\
+									\
+	mutex_lock(&opts->lock);					\
+	result = sprintf(page, "%s\n", opts->name);			\
+	mutex_unlock(&opts->lock);					\
+									\
+	return result;							\
+}									\
+									\
+static ssize_t f_uac1_opts_##name##_store(struct config_item *item,	\
+					  const char *page, size_t len)	\
+{									\
+	struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);		\
+	int ret = -EBUSY;						\
+	char *tmp;							\
+									\
+	mutex_lock(&opts->lock);					\
+	if (opts->refcnt)						\
+		goto end;						\
+									\
+	tmp = kstrndup(page, len, GFP_KERNEL);				\
+	if (tmp) {							\
+		ret = -ENOMEM;						\
+		goto end;						\
+	}								\
+	if (opts->name##_alloc)						\
+		kfree(opts->name);					\
+	opts->name##_alloc = true;					\
+	opts->name = tmp;						\
+	ret = len;							\
+									\
+end:									\
+	mutex_unlock(&opts->lock);					\
+	return ret;							\
+}									\
+									\
+CONFIGFS_ATTR(f_uac1_opts_, name)
+
+UAC1_STR_ATTRIBUTE(fn_play);
+UAC1_STR_ATTRIBUTE(fn_cap);
+UAC1_STR_ATTRIBUTE(fn_cntl);
+
+static struct configfs_attribute *f_uac1_attrs[] = {
+	&f_uac1_opts_attr_req_buf_size,
+	&f_uac1_opts_attr_req_count,
+	&f_uac1_opts_attr_audio_buf_size,
+	&f_uac1_opts_attr_fn_play,
+	&f_uac1_opts_attr_fn_cap,
+	&f_uac1_opts_attr_fn_cntl,
+	NULL,
+};
+
+static struct config_item_type f_uac1_func_type = {
+	.ct_item_ops	= &f_uac1_item_ops,
+	.ct_attrs	= f_uac1_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static void f_audio_free_inst(struct usb_function_instance *f)
+{
+	struct f_uac1_legacy_opts *opts;
+
+	opts = container_of(f, struct f_uac1_legacy_opts, func_inst);
+	if (opts->fn_play_alloc)
+		kfree(opts->fn_play);
+	if (opts->fn_cap_alloc)
+		kfree(opts->fn_cap);
+	if (opts->fn_cntl_alloc)
+		kfree(opts->fn_cntl);
+	kfree(opts);
+}
+
+static struct usb_function_instance *f_audio_alloc_inst(void)
+{
+	struct f_uac1_legacy_opts *opts;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_init(&opts->lock);
+	opts->func_inst.free_func_inst = f_audio_free_inst;
+
+	config_group_init_type_name(&opts->func_inst.group, "",
+				    &f_uac1_func_type);
+
+	opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
+	opts->req_count = UAC1_REQ_COUNT;
+	opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
+	opts->fn_play = FILE_PCM_PLAYBACK;
+	opts->fn_cap = FILE_PCM_CAPTURE;
+	opts->fn_cntl = FILE_CONTROL;
+	return &opts->func_inst;
+}
+
+static void f_audio_free(struct usb_function *f)
+{
+	struct f_audio *audio = func_to_audio(f);
+	struct f_uac1_legacy_opts *opts;
+
+	gaudio_cleanup(&audio->card);
+	opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
+	kfree(audio);
+	mutex_lock(&opts->lock);
+	--opts->refcnt;
+	mutex_unlock(&opts->lock);
+}
+
+static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+	usb_free_all_descriptors(f);
+}
+
+static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
+{
+	struct f_audio *audio;
+	struct f_uac1_legacy_opts *opts;
+
+	/* allocate and initialize one new instance */
+	audio = kzalloc(sizeof(*audio), GFP_KERNEL);
+	if (!audio)
+		return ERR_PTR(-ENOMEM);
+
+	audio->card.func.name = "g_audio";
+
+	opts = container_of(fi, struct f_uac1_legacy_opts, func_inst);
+	mutex_lock(&opts->lock);
+	++opts->refcnt;
+	mutex_unlock(&opts->lock);
+	INIT_LIST_HEAD(&audio->play_queue);
+	spin_lock_init(&audio->lock);
+
+	audio->card.func.bind = f_audio_bind;
+	audio->card.func.unbind = f_audio_unbind;
+	audio->card.func.set_alt = f_audio_set_alt;
+	audio->card.func.get_alt = f_audio_get_alt;
+	audio->card.func.setup = f_audio_setup;
+	audio->card.func.disable = f_audio_disable;
+	audio->card.func.free_func = f_audio_free;
+
+	control_selector_init(audio);
+
+	INIT_WORK(&audio->playback_work, f_audio_playback_work);
+
+	return &audio->card.func;
+}
+
+DECLARE_USB_FUNCTION_INIT(uac1_legacy, f_audio_alloc_inst, f_audio_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Bryan Wu");
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index f6a0d3a1311b..9082ce261e70 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -13,13 +13,9 @@
 
 #include <linux/usb/audio.h>
 #include <linux/usb/audio-v2.h>
-#include <linux/platform_device.h>
 #include <linux/module.h>
 
-#include <sound/core.h>
-#include <sound/pcm.h>
-#include <sound/pcm_params.h>
-
+#include "u_audio.h"
 #include "u_uac2.h"
 
 /*
@@ -51,506 +47,23 @@
 #define UNFLW_CTRL	8
 #define OVFLW_CTRL	10
 
-static const char *uac2_name = "snd_uac2";
-
-struct uac2_req {
-	struct uac2_rtd_params *pp; /* parent param */
-	struct usb_request *req;
-};
-
-struct uac2_rtd_params {
-	struct snd_uac2_chip *uac2; /* parent chip */
-	bool ep_enabled; /* if the ep is enabled */
-	/* Size of the ring buffer */
-	size_t dma_bytes;
-	unsigned char *dma_area;
-
-	struct snd_pcm_substream *ss;
-
-	/* Ring buffer */
-	ssize_t hw_ptr;
-
-	void *rbuf;
-
-	size_t period_size;
-
-	unsigned max_psize;
-	struct uac2_req *ureq;
-
-	spinlock_t lock;
-};
-
-struct snd_uac2_chip {
-	struct platform_device pdev;
-	struct platform_driver pdrv;
-
-	struct uac2_rtd_params p_prm;
-	struct uac2_rtd_params c_prm;
-
-	struct snd_card *card;
-	struct snd_pcm *pcm;
-
-	/* timekeeping for the playback endpoint */
-	unsigned int p_interval;
-	unsigned int p_residue;
-
-	/* pre-calculated values for playback iso completion */
-	unsigned int p_pktsize;
-	unsigned int p_pktsize_residue;
-	unsigned int p_framesize;
+struct f_uac2 {
+	struct g_audio g_audio;
+	u8 ac_intf, as_in_intf, as_out_intf;
+	u8 ac_alt, as_in_alt, as_out_alt;	/* needed for get_alt() */
 };
 
-#define BUFF_SIZE_MAX	(PAGE_SIZE * 16)
-#define PRD_SIZE_MAX	PAGE_SIZE
-#define MIN_PERIODS	4
-
-static struct snd_pcm_hardware uac2_pcm_hardware = {
-	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
-		 | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
-		 | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
-	.rates = SNDRV_PCM_RATE_CONTINUOUS,
-	.periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
-	.buffer_bytes_max = BUFF_SIZE_MAX,
-	.period_bytes_max = PRD_SIZE_MAX,
-	.periods_min = MIN_PERIODS,
-};
-
-struct audio_dev {
-	u8 ac_intf, ac_alt;
-	u8 as_out_intf, as_out_alt;
-	u8 as_in_intf, as_in_alt;
-
-	struct usb_ep *in_ep, *out_ep;
-	struct usb_function func;
-
-	/* The ALSA Sound Card it represents on the USB-Client side */
-	struct snd_uac2_chip uac2;
-};
-
-static inline
-struct audio_dev *func_to_agdev(struct usb_function *f)
+static inline struct f_uac2 *func_to_uac2(struct usb_function *f)
 {
-	return container_of(f, struct audio_dev, func);
+	return container_of(f, struct f_uac2, g_audio.func);
 }
 
 static inline
-struct audio_dev *uac2_to_agdev(struct snd_uac2_chip *u)
-{
-	return container_of(u, struct audio_dev, uac2);
-}
-
-static inline
-struct snd_uac2_chip *pdev_to_uac2(struct platform_device *p)
-{
-	return container_of(p, struct snd_uac2_chip, pdev);
-}
-
-static inline
-struct f_uac2_opts *agdev_to_uac2_opts(struct audio_dev *agdev)
+struct f_uac2_opts *g_audio_to_uac2_opts(struct g_audio *agdev)
 {
 	return container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
 }
 
-static inline
-uint num_channels(uint chanmask)
-{
-	uint num = 0;
-
-	while (chanmask) {
-		num += (chanmask & 1);
-		chanmask >>= 1;
-	}
-
-	return num;
-}
-
-static void
-agdev_iso_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	unsigned pending;
-	unsigned long flags;
-	unsigned int hw_ptr;
-	bool update_alsa = false;
-	int status = req->status;
-	struct uac2_req *ur = req->context;
-	struct snd_pcm_substream *substream;
-	struct uac2_rtd_params *prm = ur->pp;
-	struct snd_uac2_chip *uac2 = prm->uac2;
-
-	/* i/f shutting down */
-	if (!prm->ep_enabled || req->status == -ESHUTDOWN)
-		return;
-
-	/*
-	 * We can't really do much about bad xfers.
-	 * Afterall, the ISOCH xfers could fail legitimately.
-	 */
-	if (status)
-		pr_debug("%s: iso_complete status(%d) %d/%d\n",
-			__func__, status, req->actual, req->length);
-
-	substream = prm->ss;
-
-	/* Do nothing if ALSA isn't active */
-	if (!substream)
-		goto exit;
-
-	spin_lock_irqsave(&prm->lock, flags);
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		/*
-		 * For each IN packet, take the quotient of the current data
-		 * rate and the endpoint's interval as the base packet size.
-		 * If there is a residue from this division, add it to the
-		 * residue accumulator.
-		 */
-		req->length = uac2->p_pktsize;
-		uac2->p_residue += uac2->p_pktsize_residue;
-
-		/*
-		 * Whenever there are more bytes in the accumulator than we
-		 * need to add one more sample frame, increase this packet's
-		 * size and decrease the accumulator.
-		 */
-		if (uac2->p_residue / uac2->p_interval >= uac2->p_framesize) {
-			req->length += uac2->p_framesize;
-			uac2->p_residue -= uac2->p_framesize *
-					   uac2->p_interval;
-		}
-
-		req->actual = req->length;
-	}
-
-	pending = prm->hw_ptr % prm->period_size;
-	pending += req->actual;
-	if (pending >= prm->period_size)
-		update_alsa = true;
-
-	hw_ptr = prm->hw_ptr;
-	prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes;
-
-	spin_unlock_irqrestore(&prm->lock, flags);
-
-	/* Pack USB load in ALSA ring buffer */
-	pending = prm->dma_bytes - hw_ptr;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		if (unlikely(pending < req->actual)) {
-			memcpy(req->buf, prm->dma_area + hw_ptr, pending);
-			memcpy(req->buf + pending, prm->dma_area,
-			       req->actual - pending);
-		} else {
-			memcpy(req->buf, prm->dma_area + hw_ptr, req->actual);
-		}
-	} else {
-		if (unlikely(pending < req->actual)) {
-			memcpy(prm->dma_area + hw_ptr, req->buf, pending);
-			memcpy(prm->dma_area, req->buf + pending,
-			       req->actual - pending);
-		} else {
-			memcpy(prm->dma_area + hw_ptr, req->buf, req->actual);
-		}
-	}
-
-exit:
-	if (usb_ep_queue(ep, req, GFP_ATOMIC))
-		dev_err(&uac2->pdev.dev, "%d Error!\n", __LINE__);
-
-	if (update_alsa)
-		snd_pcm_period_elapsed(substream);
-
-	return;
-}
-
-static int
-uac2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
-{
-	struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
-	struct audio_dev *agdev = uac2_to_agdev(uac2);
-	struct f_uac2_opts *uac2_opts = agdev_to_uac2_opts(agdev);
-	struct uac2_rtd_params *prm;
-	unsigned long flags;
-	int err = 0;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac2->p_prm;
-	else
-		prm = &uac2->c_prm;
-
-	spin_lock_irqsave(&prm->lock, flags);
-
-	/* Reset */
-	prm->hw_ptr = 0;
-
-	switch (cmd) {
-	case SNDRV_PCM_TRIGGER_START:
-	case SNDRV_PCM_TRIGGER_RESUME:
-		prm->ss = substream;
-		break;
-	case SNDRV_PCM_TRIGGER_STOP:
-	case SNDRV_PCM_TRIGGER_SUSPEND:
-		prm->ss = NULL;
-		break;
-	default:
-		err = -EINVAL;
-	}
-
-	spin_unlock_irqrestore(&prm->lock, flags);
-
-	/* Clear buffer after Play stops */
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
-		memset(prm->rbuf, 0, prm->max_psize * uac2_opts->req_number);
-
-	return err;
-}
-
-static snd_pcm_uframes_t uac2_pcm_pointer(struct snd_pcm_substream *substream)
-{
-	struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
-	struct uac2_rtd_params *prm;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac2->p_prm;
-	else
-		prm = &uac2->c_prm;
-
-	return bytes_to_frames(substream->runtime, prm->hw_ptr);
-}
-
-static int uac2_pcm_hw_params(struct snd_pcm_substream *substream,
-			       struct snd_pcm_hw_params *hw_params)
-{
-	struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
-	struct uac2_rtd_params *prm;
-	int err;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac2->p_prm;
-	else
-		prm = &uac2->c_prm;
-
-	err = snd_pcm_lib_malloc_pages(substream,
-					params_buffer_bytes(hw_params));
-	if (err >= 0) {
-		prm->dma_bytes = substream->runtime->dma_bytes;
-		prm->dma_area = substream->runtime->dma_area;
-		prm->period_size = params_period_bytes(hw_params);
-	}
-
-	return err;
-}
-
-static int uac2_pcm_hw_free(struct snd_pcm_substream *substream)
-{
-	struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
-	struct uac2_rtd_params *prm;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac2->p_prm;
-	else
-		prm = &uac2->c_prm;
-
-	prm->dma_area = NULL;
-	prm->dma_bytes = 0;
-	prm->period_size = 0;
-
-	return snd_pcm_lib_free_pages(substream);
-}
-
-static int uac2_pcm_open(struct snd_pcm_substream *substream)
-{
-	struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct audio_dev *audio_dev;
-	struct f_uac2_opts *opts;
-	int p_ssize, c_ssize;
-	int p_srate, c_srate;
-	int p_chmask, c_chmask;
-
-	audio_dev = uac2_to_agdev(uac2);
-	opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
-	p_ssize = opts->p_ssize;
-	c_ssize = opts->c_ssize;
-	p_srate = opts->p_srate;
-	c_srate = opts->c_srate;
-	p_chmask = opts->p_chmask;
-	c_chmask = opts->c_chmask;
-	uac2->p_residue = 0;
-
-	runtime->hw = uac2_pcm_hardware;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		spin_lock_init(&uac2->p_prm.lock);
-		runtime->hw.rate_min = p_srate;
-		switch (p_ssize) {
-		case 3:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
-			break;
-		case 4:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
-			break;
-		default:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
-			break;
-		}
-		runtime->hw.channels_min = num_channels(p_chmask);
-		runtime->hw.period_bytes_min = 2 * uac2->p_prm.max_psize
-						/ runtime->hw.periods_min;
-	} else {
-		spin_lock_init(&uac2->c_prm.lock);
-		runtime->hw.rate_min = c_srate;
-		switch (c_ssize) {
-		case 3:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
-			break;
-		case 4:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
-			break;
-		default:
-			runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
-			break;
-		}
-		runtime->hw.channels_min = num_channels(c_chmask);
-		runtime->hw.period_bytes_min = 2 * uac2->c_prm.max_psize
-						/ runtime->hw.periods_min;
-	}
-
-	runtime->hw.rate_max = runtime->hw.rate_min;
-	runtime->hw.channels_max = runtime->hw.channels_min;
-
-	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
-
-	return 0;
-}
-
-/* ALSA cries without these function pointers */
-static int uac2_pcm_null(struct snd_pcm_substream *substream)
-{
-	return 0;
-}
-
-static struct snd_pcm_ops uac2_pcm_ops = {
-	.open = uac2_pcm_open,
-	.close = uac2_pcm_null,
-	.ioctl = snd_pcm_lib_ioctl,
-	.hw_params = uac2_pcm_hw_params,
-	.hw_free = uac2_pcm_hw_free,
-	.trigger = uac2_pcm_trigger,
-	.pointer = uac2_pcm_pointer,
-	.prepare = uac2_pcm_null,
-};
-
-static int snd_uac2_probe(struct platform_device *pdev)
-{
-	struct snd_uac2_chip *uac2 = pdev_to_uac2(pdev);
-	struct snd_card *card;
-	struct snd_pcm *pcm;
-	struct audio_dev *audio_dev;
-	struct f_uac2_opts *opts;
-	int err;
-	int p_chmask, c_chmask;
-
-	audio_dev = uac2_to_agdev(uac2);
-	opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
-	p_chmask = opts->p_chmask;
-	c_chmask = opts->c_chmask;
-
-	/* Choose any slot, with no id */
-	err = snd_card_new(&pdev->dev, -1, NULL, THIS_MODULE, 0, &card);
-	if (err < 0)
-		return err;
-
-	uac2->card = card;
-
-	/*
-	 * Create first PCM device
-	 * Create a substream only for non-zero channel streams
-	 */
-	err = snd_pcm_new(uac2->card, "UAC2 PCM", 0,
-			       p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
-	if (err < 0)
-		goto snd_fail;
-
-	strcpy(pcm->name, "UAC2 PCM");
-	pcm->private_data = uac2;
-
-	uac2->pcm = pcm;
-
-	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac2_pcm_ops);
-	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac2_pcm_ops);
-
-	strcpy(card->driver, "UAC2_Gadget");
-	strcpy(card->shortname, "UAC2_Gadget");
-	sprintf(card->longname, "UAC2_Gadget %i", pdev->id);
-
-	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
-		snd_dma_continuous_data(GFP_KERNEL), 0, BUFF_SIZE_MAX);
-
-	err = snd_card_register(card);
-	if (!err) {
-		platform_set_drvdata(pdev, card);
-		return 0;
-	}
-
-snd_fail:
-	snd_card_free(card);
-
-	uac2->pcm = NULL;
-	uac2->card = NULL;
-
-	return err;
-}
-
-static int snd_uac2_remove(struct platform_device *pdev)
-{
-	struct snd_card *card = platform_get_drvdata(pdev);
-
-	if (card)
-		return snd_card_free(card);
-
-	return 0;
-}
-
-static void snd_uac2_release(struct device *dev)
-{
-	dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
-}
-
-static int alsa_uac2_init(struct audio_dev *agdev)
-{
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
-	int err;
-
-	uac2->pdrv.probe = snd_uac2_probe;
-	uac2->pdrv.remove = snd_uac2_remove;
-	uac2->pdrv.driver.name = uac2_name;
-
-	uac2->pdev.id = 0;
-	uac2->pdev.name = uac2_name;
-	uac2->pdev.dev.release = snd_uac2_release;
-
-	/* Register snd_uac2 driver */
-	err = platform_driver_register(&uac2->pdrv);
-	if (err)
-		return err;
-
-	/* Register snd_uac2 device */
-	err = platform_device_register(&uac2->pdev);
-	if (err)
-		platform_driver_unregister(&uac2->pdrv);
-
-	return err;
-}
-
-static void alsa_uac2_exit(struct audio_dev *agdev)
-{
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
-
-	platform_driver_unregister(&uac2->pdrv);
-	platform_device_unregister(&uac2->pdev);
-}
-
-
 /* --------- USB Function Interface ------------- */
 
 enum {
@@ -938,32 +451,6 @@ struct cntrl_range_lay3 {
 	__u32	dRES;
 } __packed;
 
-static inline void
-free_ep(struct uac2_rtd_params *prm, struct usb_ep *ep)
-{
-	struct snd_uac2_chip *uac2 = prm->uac2;
-	struct audio_dev *agdev = uac2_to_agdev(uac2);
-	struct f_uac2_opts *uac2_opts = agdev_to_uac2_opts(agdev);
-	int i;
-
-	if (!prm->ep_enabled)
-		return;
-
-	prm->ep_enabled = false;
-
-	for (i = 0; i < uac2_opts->req_number; i++) {
-		if (prm->ureq[i].req) {
-			usb_ep_dequeue(ep, prm->ureq[i].req);
-			usb_ep_free_request(ep, prm->ureq[i].req);
-			prm->ureq[i].req = NULL;
-		}
-	}
-
-	if (usb_ep_disable(ep))
-		dev_err(&uac2->pdev.dev,
-			"%s:%d Error!\n", __func__, __LINE__);
-}
-
 static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 	struct usb_endpoint_descriptor *ep_desc,
 	unsigned int factor, bool is_playback)
@@ -990,12 +477,11 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 static int
 afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 {
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct f_uac2 *uac2 = func_to_uac2(fn);
+	struct g_audio *agdev = func_to_g_audio(fn);
 	struct usb_composite_dev *cdev = cfg->cdev;
 	struct usb_gadget *gadget = cdev->gadget;
-	struct device *dev = &uac2->pdev.dev;
-	struct uac2_rtd_params *prm;
+	struct device *dev = &gadget->dev;
 	struct f_uac2_opts *uac2_opts;
 	struct usb_string *us;
 	int ret;
@@ -1042,8 +528,8 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		return ret;
 	}
 	std_ac_if_desc.bInterfaceNumber = ret;
-	agdev->ac_intf = ret;
-	agdev->ac_alt = 0;
+	uac2->ac_intf = ret;
+	uac2->ac_alt = 0;
 
 	ret = usb_interface_id(cfg, fn);
 	if (ret < 0) {
@@ -1052,8 +538,8 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	}
 	std_as_out_if0_desc.bInterfaceNumber = ret;
 	std_as_out_if1_desc.bInterfaceNumber = ret;
-	agdev->as_out_intf = ret;
-	agdev->as_out_alt = 0;
+	uac2->as_out_intf = ret;
+	uac2->as_out_alt = 0;
 
 	ret = usb_interface_id(cfg, fn);
 	if (ret < 0) {
@@ -1062,8 +548,14 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	}
 	std_as_in_if0_desc.bInterfaceNumber = ret;
 	std_as_in_if1_desc.bInterfaceNumber = ret;
-	agdev->as_in_intf = ret;
-	agdev->as_in_alt = 0;
+	uac2->as_in_intf = ret;
+	uac2->as_in_alt = 0;
+
+	/* Calculate wMaxPacketSize according to audio bandwidth */
+	set_ep_max_packet_size(uac2_opts, &fs_epin_desc, 1000, true);
+	set_ep_max_packet_size(uac2_opts, &fs_epout_desc, 1000, false);
+	set_ep_max_packet_size(uac2_opts, &hs_epin_desc, 8000, true);
+	set_ep_max_packet_size(uac2_opts, &hs_epout_desc, 8000, false);
 
 	agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
 	if (!agdev->out_ep) {
@@ -1077,14 +569,10 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		return ret;
 	}
 
-	uac2->p_prm.uac2 = uac2;
-	uac2->c_prm.uac2 = uac2;
-
-	/* Calculate wMaxPacketSize according to audio bandwidth */
-	set_ep_max_packet_size(uac2_opts, &fs_epin_desc, 1000, true);
-	set_ep_max_packet_size(uac2_opts, &fs_epout_desc, 1000, false);
-	set_ep_max_packet_size(uac2_opts, &hs_epin_desc, 8000, true);
-	set_ep_max_packet_size(uac2_opts, &hs_epout_desc, 8000, false);
+	agdev->in_ep_maxpsize = max(fs_epin_desc.wMaxPacketSize,
+					hs_epin_desc.wMaxPacketSize);
+	agdev->out_ep_maxpsize = max(fs_epout_desc.wMaxPacketSize,
+					hs_epout_desc.wMaxPacketSize);
 
 	hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
 	hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
@@ -1094,48 +582,23 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	if (ret)
 		return ret;
 
-	prm = &agdev->uac2.c_prm;
-	prm->max_psize = hs_epout_desc.wMaxPacketSize;
-	prm->ureq = kcalloc(uac2_opts->req_number, sizeof(struct uac2_req),
-			GFP_KERNEL);
-	if (!prm->ureq) {
-		ret = -ENOMEM;
-		goto err_free_descs;
-	}
-	prm->rbuf = kcalloc(uac2_opts->req_number, prm->max_psize, GFP_KERNEL);
-	if (!prm->rbuf) {
-		prm->max_psize = 0;
-		ret = -ENOMEM;
-		goto err_free_descs;
-	}
-
-	prm = &agdev->uac2.p_prm;
-	prm->max_psize = hs_epin_desc.wMaxPacketSize;
-	prm->ureq = kcalloc(uac2_opts->req_number, sizeof(struct uac2_req),
-			GFP_KERNEL);
-	if (!prm->ureq) {
-		ret = -ENOMEM;
-		goto err_free_descs;
-	}
-	prm->rbuf = kcalloc(uac2_opts->req_number, prm->max_psize, GFP_KERNEL);
-	if (!prm->rbuf) {
-		prm->max_psize = 0;
-		ret = -ENOMEM;
-		goto err_no_memory;
-	}
+	agdev->gadget = gadget;
 
-	ret = alsa_uac2_init(agdev);
+	agdev->params.p_chmask = uac2_opts->p_chmask;
+	agdev->params.p_srate = uac2_opts->p_srate;
+	agdev->params.p_ssize = uac2_opts->p_ssize;
+	agdev->params.c_chmask = uac2_opts->c_chmask;
+	agdev->params.c_srate = uac2_opts->c_srate;
+	agdev->params.c_ssize = uac2_opts->c_ssize;
+	agdev->params.req_number = uac2_opts->req_number;
+	ret = g_audio_setup(agdev, "UAC2 PCM", "UAC2_Gadget");
 	if (ret)
-		goto err_no_memory;
+		goto err_free_descs;
 	return 0;
 
-err_no_memory:
-	kfree(agdev->uac2.p_prm.ureq);
-	kfree(agdev->uac2.c_prm.ureq);
-	kfree(agdev->uac2.p_prm.rbuf);
-	kfree(agdev->uac2.c_prm.rbuf);
 err_free_descs:
 	usb_free_all_descriptors(fn);
+	agdev->gadget = NULL;
 	return ret;
 }
 
@@ -1143,15 +606,10 @@ static int
 afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
 {
 	struct usb_composite_dev *cdev = fn->config->cdev;
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct f_uac2_opts *opts = agdev_to_uac2_opts(agdev);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct f_uac2 *uac2 = func_to_uac2(fn);
 	struct usb_gadget *gadget = cdev->gadget;
-	struct device *dev = &uac2->pdev.dev;
-	struct usb_request *req;
-	struct usb_ep *ep;
-	struct uac2_rtd_params *prm;
-	int req_len, i;
+	struct device *dev = &gadget->dev;
+	int ret = 0;
 
 	/* No i/f has more than 2 alt settings */
 	if (alt > 1) {
@@ -1159,7 +617,7 @@ afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
 		return -EINVAL;
 	}
 
-	if (intf == agdev->ac_intf) {
+	if (intf == uac2->ac_intf) {
 		/* Control I/f has only 1 AltSetting - 0 */
 		if (alt) {
 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
@@ -1168,95 +626,42 @@ afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
 		return 0;
 	}
 
-	if (intf == agdev->as_out_intf) {
-		ep = agdev->out_ep;
-		prm = &uac2->c_prm;
-		config_ep_by_speed(gadget, fn, ep);
-		agdev->as_out_alt = alt;
-		req_len = prm->max_psize;
-	} else if (intf == agdev->as_in_intf) {
-		unsigned int factor, rate;
-		struct usb_endpoint_descriptor *ep_desc;
-
-		ep = agdev->in_ep;
-		prm = &uac2->p_prm;
-		config_ep_by_speed(gadget, fn, ep);
-		agdev->as_in_alt = alt;
-
-		/* pre-calculate the playback endpoint's interval */
-		if (gadget->speed == USB_SPEED_FULL) {
-			ep_desc = &fs_epin_desc;
-			factor = 1000;
-		} else {
-			ep_desc = &hs_epin_desc;
-			factor = 8000;
-		}
-
-		/* pre-compute some values for iso_complete() */
-		uac2->p_framesize = opts->p_ssize *
-				    num_channels(opts->p_chmask);
-		rate = opts->p_srate * uac2->p_framesize;
-		uac2->p_interval = factor / (1 << (ep_desc->bInterval - 1));
-		uac2->p_pktsize = min_t(unsigned int, rate / uac2->p_interval,
-					prm->max_psize);
+	if (intf == uac2->as_out_intf) {
+		uac2->as_out_alt = alt;
 
-		if (uac2->p_pktsize < prm->max_psize)
-			uac2->p_pktsize_residue = rate % uac2->p_interval;
+		if (alt)
+			ret = u_audio_start_capture(&uac2->g_audio);
 		else
-			uac2->p_pktsize_residue = 0;
+			u_audio_stop_capture(&uac2->g_audio);
+	} else if (intf == uac2->as_in_intf) {
+		uac2->as_in_alt = alt;
 
-		req_len = uac2->p_pktsize;
-		uac2->p_residue = 0;
+		if (alt)
+			ret = u_audio_start_playback(&uac2->g_audio);
+		else
+			u_audio_stop_playback(&uac2->g_audio);
 	} else {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		return -EINVAL;
 	}
 
-	if (alt == 0) {
-		free_ep(prm, ep);
-		return 0;
-	}
-
-	prm->ep_enabled = true;
-	usb_ep_enable(ep);
-
-	for (i = 0; i < opts->req_number; i++) {
-		if (!prm->ureq[i].req) {
-			req = usb_ep_alloc_request(ep, GFP_ATOMIC);
-			if (req == NULL)
-				return -ENOMEM;
-
-			prm->ureq[i].req = req;
-			prm->ureq[i].pp = prm;
-
-			req->zero = 0;
-			req->context = &prm->ureq[i];
-			req->length = req_len;
-			req->complete = agdev_iso_complete;
-			req->buf = prm->rbuf + i * prm->max_psize;
-		}
-
-		if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
-			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
-	}
-
-	return 0;
+	return ret;
 }
 
 static int
 afunc_get_alt(struct usb_function *fn, unsigned intf)
 {
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
-
-	if (intf == agdev->ac_intf)
-		return agdev->ac_alt;
-	else if (intf == agdev->as_out_intf)
-		return agdev->as_out_alt;
-	else if (intf == agdev->as_in_intf)
-		return agdev->as_in_alt;
+	struct f_uac2 *uac2 = func_to_uac2(fn);
+	struct g_audio *agdev = func_to_g_audio(fn);
+
+	if (intf == uac2->ac_intf)
+		return uac2->ac_alt;
+	else if (intf == uac2->as_out_intf)
+		return uac2->as_out_alt;
+	else if (intf == uac2->as_in_intf)
+		return uac2->as_in_alt;
 	else
-		dev_err(&uac2->pdev.dev,
+		dev_err(&agdev->gadget->dev,
 			"%s:%d Invalid Interface %d!\n",
 			__func__, __LINE__, intf);
 
@@ -1266,22 +671,19 @@ afunc_get_alt(struct usb_function *fn, unsigned intf)
 static void
 afunc_disable(struct usb_function *fn)
 {
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
-
-	free_ep(&uac2->p_prm, agdev->in_ep);
-	agdev->as_in_alt = 0;
+	struct f_uac2 *uac2 = func_to_uac2(fn);
 
-	free_ep(&uac2->c_prm, agdev->out_ep);
-	agdev->as_out_alt = 0;
+	uac2->as_in_alt = 0;
+	uac2->as_out_alt = 0;
+	u_audio_stop_capture(&uac2->g_audio);
+	u_audio_stop_playback(&uac2->g_audio);
 }
 
 static int
 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
 	struct usb_request *req = fn->config->cdev->req;
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct g_audio *agdev = func_to_g_audio(fn);
 	struct f_uac2_opts *opts;
 	u16 w_length = le16_to_cpu(cr->wLength);
 	u16 w_index = le16_to_cpu(cr->wIndex);
@@ -1291,7 +693,7 @@ in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	int value = -EOPNOTSUPP;
 	int p_srate, c_srate;
 
-	opts = agdev_to_uac2_opts(agdev);
+	opts = g_audio_to_uac2_opts(agdev);
 	p_srate = opts->p_srate;
 	c_srate = opts->c_srate;
 
@@ -1310,7 +712,7 @@ in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 		*(u8 *)req->buf = 1;
 		value = min_t(unsigned, w_length, 1);
 	} else {
-		dev_err(&uac2->pdev.dev,
+		dev_err(&agdev->gadget->dev,
 			"%s:%d control_selector=%d TODO!\n",
 			__func__, __LINE__, control_selector);
 	}
@@ -1322,8 +724,7 @@ static int
 in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
 	struct usb_request *req = fn->config->cdev->req;
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct g_audio *agdev = func_to_g_audio(fn);
 	struct f_uac2_opts *opts;
 	u16 w_length = le16_to_cpu(cr->wLength);
 	u16 w_index = le16_to_cpu(cr->wIndex);
@@ -1334,7 +735,7 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	int value = -EOPNOTSUPP;
 	int p_srate, c_srate;
 
-	opts = agdev_to_uac2_opts(agdev);
+	opts = g_audio_to_uac2_opts(agdev);
 	p_srate = opts->p_srate;
 	c_srate = opts->c_srate;
 
@@ -1353,7 +754,7 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 		value = min_t(unsigned, w_length, sizeof r);
 		memcpy(req->buf, &r, value);
 	} else {
-		dev_err(&uac2->pdev.dev,
+		dev_err(&agdev->gadget->dev,
 			"%s:%d control_selector=%d TODO!\n",
 			__func__, __LINE__, control_selector);
 	}
@@ -1388,13 +789,13 @@ out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 static int
 setup_rq_inf(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct f_uac2 *uac2 = func_to_uac2(fn);
+	struct g_audio *agdev = func_to_g_audio(fn);
 	u16 w_index = le16_to_cpu(cr->wIndex);
 	u8 intf = w_index & 0xff;
 
-	if (intf != agdev->ac_intf) {
-		dev_err(&uac2->pdev.dev,
+	if (intf != uac2->ac_intf) {
+		dev_err(&agdev->gadget->dev,
 			"%s:%d Error!\n", __func__, __LINE__);
 		return -EOPNOTSUPP;
 	}
@@ -1411,8 +812,7 @@ static int
 afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 {
 	struct usb_composite_dev *cdev = fn->config->cdev;
-	struct audio_dev *agdev = func_to_agdev(fn);
-	struct snd_uac2_chip *uac2 = &agdev->uac2;
+	struct g_audio *agdev = func_to_g_audio(fn);
 	struct usb_request *req = cdev->req;
 	u16 w_length = le16_to_cpu(cr->wLength);
 	int value = -EOPNOTSUPP;
@@ -1424,14 +824,15 @@ afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 	if ((cr->bRequestType & USB_RECIP_MASK) == USB_RECIP_INTERFACE)
 		value = setup_rq_inf(fn, cr);
 	else
-		dev_err(&uac2->pdev.dev, "%s:%d Error!\n", __func__, __LINE__);
+		dev_err(&agdev->gadget->dev, "%s:%d Error!\n",
+				__func__, __LINE__);
 
 	if (value >= 0) {
 		req->length = value;
 		req->zero = value < w_length;
 		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 		if (value < 0) {
-			dev_err(&uac2->pdev.dev,
+			dev_err(&agdev->gadget->dev,
 				"%s:%d Error!\n", __func__, __LINE__);
 			req->status = 0;
 		}
@@ -1557,10 +958,10 @@ static struct usb_function_instance *afunc_alloc_inst(void)
 
 static void afunc_free(struct usb_function *f)
 {
-	struct audio_dev *agdev;
+	struct g_audio *agdev;
 	struct f_uac2_opts *opts;
 
-	agdev = func_to_agdev(f);
+	agdev = func_to_g_audio(f);
 	opts = container_of(f->fi, struct f_uac2_opts, func_inst);
 	kfree(agdev);
 	mutex_lock(&opts->lock);
@@ -1570,27 +971,21 @@ static void afunc_free(struct usb_function *f)
 
 static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
 {
-	struct audio_dev *agdev = func_to_agdev(f);
-	struct uac2_rtd_params *prm;
+	struct g_audio *agdev = func_to_g_audio(f);
 
-	alsa_uac2_exit(agdev);
-
-	prm = &agdev->uac2.p_prm;
-	kfree(prm->rbuf);
-
-	prm = &agdev->uac2.c_prm;
-	kfree(prm->rbuf);
-	kfree(prm->ureq);
+	g_audio_cleanup(agdev);
 	usb_free_all_descriptors(f);
+
+	agdev->gadget = NULL;
 }
 
 static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
 {
-	struct audio_dev *agdev;
+	struct f_uac2	*uac2;
 	struct f_uac2_opts *opts;
 
-	agdev = kzalloc(sizeof(*agdev), GFP_KERNEL);
-	if (agdev == NULL)
+	uac2 = kzalloc(sizeof(*uac2), GFP_KERNEL);
+	if (uac2 == NULL)
 		return ERR_PTR(-ENOMEM);
 
 	opts = container_of(fi, struct f_uac2_opts, func_inst);
@@ -1598,16 +993,16 @@ static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
 	++opts->refcnt;
 	mutex_unlock(&opts->lock);
 
-	agdev->func.name = "uac2_func";
-	agdev->func.bind = afunc_bind;
-	agdev->func.unbind = afunc_unbind;
-	agdev->func.set_alt = afunc_set_alt;
-	agdev->func.get_alt = afunc_get_alt;
-	agdev->func.disable = afunc_disable;
-	agdev->func.setup = afunc_setup;
-	agdev->func.free_func = afunc_free;
+	uac2->g_audio.func.name = "uac2_func";
+	uac2->g_audio.func.bind = afunc_bind;
+	uac2->g_audio.func.unbind = afunc_unbind;
+	uac2->g_audio.func.set_alt = afunc_set_alt;
+	uac2->g_audio.func.get_alt = afunc_get_alt;
+	uac2->g_audio.func.disable = afunc_disable;
+	uac2->g_audio.func.setup = afunc_setup;
+	uac2->g_audio.func.free_func = afunc_free;
 
-	return &agdev->func;
+	return &uac2->g_audio.func;
 }
 
 DECLARE_USB_FUNCTION_INIT(uac2, afunc_alloc_inst, afunc_alloc);
diff --git a/drivers/usb/gadget/function/storage_common.h b/drivers/usb/gadget/function/storage_common.h
index e69848994cb4..e0814a960132 100644
--- a/drivers/usb/gadget/function/storage_common.h
+++ b/drivers/usb/gadget/function/storage_common.h
@@ -133,9 +133,10 @@ static inline bool fsg_lun_is_open(struct fsg_lun *curlun)
 #define FSG_MAX_LUNS	16
 
 enum fsg_buffer_state {
+	BUF_STATE_SENDING = -2,
+	BUF_STATE_RECEIVING,
 	BUF_STATE_EMPTY = 0,
-	BUF_STATE_FULL,
-	BUF_STATE_BUSY
+	BUF_STATE_FULL
 };
 
 struct fsg_buffhd {
@@ -151,23 +152,14 @@ struct fsg_buffhd {
 	unsigned int			bulk_out_intended_length;
 
 	struct usb_request		*inreq;
-	int				inreq_busy;
 	struct usb_request		*outreq;
-	int				outreq_busy;
 };
 
 enum fsg_state {
-	/* This one isn't used anywhere */
-	FSG_STATE_COMMAND_PHASE = -10,
-	FSG_STATE_DATA_PHASE,
-	FSG_STATE_STATUS_PHASE,
-
-	FSG_STATE_IDLE = 0,
+	FSG_STATE_NORMAL,
 	FSG_STATE_ABORT_BULK_OUT,
-	FSG_STATE_RESET,
-	FSG_STATE_INTERFACE_CHANGE,
+	FSG_STATE_PROTOCOL_RESET,
 	FSG_STATE_CONFIG_CHANGE,
-	FSG_STATE_DISCONNECT,
 	FSG_STATE_EXIT,
 	FSG_STATE_TERMINATED
 };
diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
new file mode 100644
index 000000000000..5dd73b9e5172
--- /dev/null
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -0,0 +1,662 @@
+/*
+ * u_audio.c -- interface to USB gadget "ALSA sound card" utilities
+ *
+ * Copyright (C) 2016
+ * Author: Ruslan Bilovol <ruslan.bilovol@gmail.com>
+ *
+ * Sound card implementation was cut-and-pasted with changes
+ * from f_uac2.c and has:
+ *    Copyright (C) 2011
+ *    Yadwinder Singh (yadi.brar01@gmail.com)
+ *    Jaswinder Singh (jaswinder.singh@linaro.org)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "u_audio.h"
+
+#define BUFF_SIZE_MAX	(PAGE_SIZE * 16)
+#define PRD_SIZE_MAX	PAGE_SIZE
+#define MIN_PERIODS	4
+
+struct uac_req {
+	struct uac_rtd_params *pp; /* parent param */
+	struct usb_request *req;
+};
+
+/* Runtime data params for one stream */
+struct uac_rtd_params {
+	struct snd_uac_chip *uac; /* parent chip */
+	bool ep_enabled; /* if the ep is enabled */
+	/* Size of the ring buffer */
+	size_t dma_bytes;
+	unsigned char *dma_area;
+
+	struct snd_pcm_substream *ss;
+
+	/* Ring buffer */
+	ssize_t hw_ptr;
+
+	void *rbuf;
+
+	size_t period_size;
+
+	unsigned max_psize;	/* MaxPacketSize of endpoint */
+	struct uac_req *ureq;
+
+	spinlock_t lock;
+};
+
+struct snd_uac_chip {
+	struct g_audio *audio_dev;
+
+	struct uac_rtd_params p_prm;
+	struct uac_rtd_params c_prm;
+
+	struct snd_card *card;
+	struct snd_pcm *pcm;
+
+	/* timekeeping for the playback endpoint */
+	unsigned int p_interval;
+	unsigned int p_residue;
+
+	/* pre-calculated values for playback iso completion */
+	unsigned int p_pktsize;
+	unsigned int p_pktsize_residue;
+	unsigned int p_framesize;
+};
+
+static struct snd_pcm_hardware uac_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
+		 | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
+		 | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
+	.rates = SNDRV_PCM_RATE_CONTINUOUS,
+	.periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
+	.buffer_bytes_max = BUFF_SIZE_MAX,
+	.period_bytes_max = PRD_SIZE_MAX,
+	.periods_min = MIN_PERIODS,
+};
+
+static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	unsigned pending;
+	unsigned long flags;
+	unsigned int hw_ptr;
+	bool update_alsa = false;
+	int status = req->status;
+	struct uac_req *ur = req->context;
+	struct snd_pcm_substream *substream;
+	struct uac_rtd_params *prm = ur->pp;
+	struct snd_uac_chip *uac = prm->uac;
+
+	/* i/f shutting down */
+	if (!prm->ep_enabled || req->status == -ESHUTDOWN)
+		return;
+
+	/*
+	 * We can't really do much about bad xfers.
+	 * Afterall, the ISOCH xfers could fail legitimately.
+	 */
+	if (status)
+		pr_debug("%s: iso_complete status(%d) %d/%d\n",
+			__func__, status, req->actual, req->length);
+
+	substream = prm->ss;
+
+	/* Do nothing if ALSA isn't active */
+	if (!substream)
+		goto exit;
+
+	spin_lock_irqsave(&prm->lock, flags);
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		/*
+		 * For each IN packet, take the quotient of the current data
+		 * rate and the endpoint's interval as the base packet size.
+		 * If there is a residue from this division, add it to the
+		 * residue accumulator.
+		 */
+		req->length = uac->p_pktsize;
+		uac->p_residue += uac->p_pktsize_residue;
+
+		/*
+		 * Whenever there are more bytes in the accumulator than we
+		 * need to add one more sample frame, increase this packet's
+		 * size and decrease the accumulator.
+		 */
+		if (uac->p_residue / uac->p_interval >= uac->p_framesize) {
+			req->length += uac->p_framesize;
+			uac->p_residue -= uac->p_framesize *
+					   uac->p_interval;
+		}
+
+		req->actual = req->length;
+	}
+
+	pending = prm->hw_ptr % prm->period_size;
+	pending += req->actual;
+	if (pending >= prm->period_size)
+		update_alsa = true;
+
+	hw_ptr = prm->hw_ptr;
+	prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes;
+
+	spin_unlock_irqrestore(&prm->lock, flags);
+
+	/* Pack USB load in ALSA ring buffer */
+	pending = prm->dma_bytes - hw_ptr;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		if (unlikely(pending < req->actual)) {
+			memcpy(req->buf, prm->dma_area + hw_ptr, pending);
+			memcpy(req->buf + pending, prm->dma_area,
+			       req->actual - pending);
+		} else {
+			memcpy(req->buf, prm->dma_area + hw_ptr, req->actual);
+		}
+	} else {
+		if (unlikely(pending < req->actual)) {
+			memcpy(prm->dma_area + hw_ptr, req->buf, pending);
+			memcpy(prm->dma_area, req->buf + pending,
+			       req->actual - pending);
+		} else {
+			memcpy(prm->dma_area + hw_ptr, req->buf, req->actual);
+		}
+	}
+
+exit:
+	if (usb_ep_queue(ep, req, GFP_ATOMIC))
+		dev_err(uac->card->dev, "%d Error!\n", __LINE__);
+
+	if (update_alsa)
+		snd_pcm_period_elapsed(substream);
+}
+
+static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+	struct g_audio *audio_dev;
+	struct uac_params *params;
+	unsigned long flags;
+	int err = 0;
+
+	audio_dev = uac->audio_dev;
+	params = &audio_dev->params;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	spin_lock_irqsave(&prm->lock, flags);
+
+	/* Reset */
+	prm->hw_ptr = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		prm->ss = substream;
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		prm->ss = NULL;
+		break;
+	default:
+		err = -EINVAL;
+	}
+
+	spin_unlock_irqrestore(&prm->lock, flags);
+
+	/* Clear buffer after Play stops */
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
+		memset(prm->rbuf, 0, prm->max_psize * params->req_number);
+
+	return err;
+}
+
+static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	return bytes_to_frames(substream->runtime, prm->hw_ptr);
+}
+
+static int uac_pcm_hw_params(struct snd_pcm_substream *substream,
+			       struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+	int err;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	err = snd_pcm_lib_malloc_pages(substream,
+					params_buffer_bytes(hw_params));
+	if (err >= 0) {
+		prm->dma_bytes = substream->runtime->dma_bytes;
+		prm->dma_area = substream->runtime->dma_area;
+		prm->period_size = params_period_bytes(hw_params);
+	}
+
+	return err;
+}
+
+static int uac_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct uac_rtd_params *prm;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		prm = &uac->p_prm;
+	else
+		prm = &uac->c_prm;
+
+	prm->dma_area = NULL;
+	prm->dma_bytes = 0;
+	prm->period_size = 0;
+
+	return snd_pcm_lib_free_pages(substream);
+}
+
+static int uac_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct g_audio *audio_dev;
+	struct uac_params *params;
+	int p_ssize, c_ssize;
+	int p_srate, c_srate;
+	int p_chmask, c_chmask;
+
+	audio_dev = uac->audio_dev;
+	params = &audio_dev->params;
+	p_ssize = params->p_ssize;
+	c_ssize = params->c_ssize;
+	p_srate = params->p_srate;
+	c_srate = params->c_srate;
+	p_chmask = params->p_chmask;
+	c_chmask = params->c_chmask;
+	uac->p_residue = 0;
+
+	runtime->hw = uac_pcm_hardware;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		spin_lock_init(&uac->p_prm.lock);
+		runtime->hw.rate_min = p_srate;
+		switch (p_ssize) {
+		case 3:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
+			break;
+		case 4:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
+			break;
+		default:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
+			break;
+		}
+		runtime->hw.channels_min = num_channels(p_chmask);
+		runtime->hw.period_bytes_min = 2 * uac->p_prm.max_psize
+						/ runtime->hw.periods_min;
+	} else {
+		spin_lock_init(&uac->c_prm.lock);
+		runtime->hw.rate_min = c_srate;
+		switch (c_ssize) {
+		case 3:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
+			break;
+		case 4:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
+			break;
+		default:
+			runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
+			break;
+		}
+		runtime->hw.channels_min = num_channels(c_chmask);
+		runtime->hw.period_bytes_min = 2 * uac->c_prm.max_psize
+						/ runtime->hw.periods_min;
+	}
+
+	runtime->hw.rate_max = runtime->hw.rate_min;
+	runtime->hw.channels_max = runtime->hw.channels_min;
+
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+
+	return 0;
+}
+
+/* ALSA cries without these function pointers */
+static int uac_pcm_null(struct snd_pcm_substream *substream)
+{
+	return 0;
+}
+
+static struct snd_pcm_ops uac_pcm_ops = {
+	.open = uac_pcm_open,
+	.close = uac_pcm_null,
+	.ioctl = snd_pcm_lib_ioctl,
+	.hw_params = uac_pcm_hw_params,
+	.hw_free = uac_pcm_hw_free,
+	.trigger = uac_pcm_trigger,
+	.pointer = uac_pcm_pointer,
+	.prepare = uac_pcm_null,
+};
+
+static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
+{
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev;
+	struct uac_params *params;
+	int i;
+
+	if (!prm->ep_enabled)
+		return;
+
+	prm->ep_enabled = false;
+
+	audio_dev = uac->audio_dev;
+	params = &audio_dev->params;
+
+	for (i = 0; i < params->req_number; i++) {
+		if (prm->ureq[i].req) {
+			usb_ep_dequeue(ep, prm->ureq[i].req);
+			usb_ep_free_request(ep, prm->ureq[i].req);
+			prm->ureq[i].req = NULL;
+		}
+	}
+
+	if (usb_ep_disable(ep))
+		dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
+}
+
+
+int u_audio_start_capture(struct g_audio *audio_dev)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct usb_gadget *gadget = audio_dev->gadget;
+	struct device *dev = &gadget->dev;
+	struct usb_request *req;
+	struct usb_ep *ep;
+	struct uac_rtd_params *prm;
+	struct uac_params *params = &audio_dev->params;
+	int req_len, i;
+
+	ep = audio_dev->out_ep;
+	prm = &uac->c_prm;
+	config_ep_by_speed(gadget, &audio_dev->func, ep);
+	req_len = prm->max_psize;
+
+	prm->ep_enabled = true;
+	usb_ep_enable(ep);
+
+	for (i = 0; i < params->req_number; i++) {
+		if (!prm->ureq[i].req) {
+			req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+			if (req == NULL)
+				return -ENOMEM;
+
+			prm->ureq[i].req = req;
+			prm->ureq[i].pp = prm;
+
+			req->zero = 0;
+			req->context = &prm->ureq[i];
+			req->length = req_len;
+			req->complete = u_audio_iso_complete;
+			req->buf = prm->rbuf + i * prm->max_psize;
+		}
+
+		if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
+			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(u_audio_start_capture);
+
+void u_audio_stop_capture(struct g_audio *audio_dev)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+
+	free_ep(&uac->c_prm, audio_dev->out_ep);
+}
+EXPORT_SYMBOL_GPL(u_audio_stop_capture);
+
+int u_audio_start_playback(struct g_audio *audio_dev)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+	struct usb_gadget *gadget = audio_dev->gadget;
+	struct device *dev = &gadget->dev;
+	struct usb_request *req;
+	struct usb_ep *ep;
+	struct uac_rtd_params *prm;
+	struct uac_params *params = &audio_dev->params;
+	unsigned int factor, rate;
+	const struct usb_endpoint_descriptor *ep_desc;
+	int req_len, i;
+
+	ep = audio_dev->in_ep;
+	prm = &uac->p_prm;
+	config_ep_by_speed(gadget, &audio_dev->func, ep);
+
+	ep_desc = ep->desc;
+
+	/* pre-calculate the playback endpoint's interval */
+	if (gadget->speed == USB_SPEED_FULL)
+		factor = 1000;
+	else
+		factor = 8000;
+
+	/* pre-compute some values for iso_complete() */
+	uac->p_framesize = params->p_ssize *
+			    num_channels(params->p_chmask);
+	rate = params->p_srate * uac->p_framesize;
+	uac->p_interval = factor / (1 << (ep_desc->bInterval - 1));
+	uac->p_pktsize = min_t(unsigned int, rate / uac->p_interval,
+				prm->max_psize);
+
+	if (uac->p_pktsize < prm->max_psize)
+		uac->p_pktsize_residue = rate % uac->p_interval;
+	else
+		uac->p_pktsize_residue = 0;
+
+	req_len = uac->p_pktsize;
+	uac->p_residue = 0;
+
+	prm->ep_enabled = true;
+	usb_ep_enable(ep);
+
+	for (i = 0; i < params->req_number; i++) {
+		if (!prm->ureq[i].req) {
+			req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+			if (req == NULL)
+				return -ENOMEM;
+
+			prm->ureq[i].req = req;
+			prm->ureq[i].pp = prm;
+
+			req->zero = 0;
+			req->context = &prm->ureq[i];
+			req->length = req_len;
+			req->complete = u_audio_iso_complete;
+			req->buf = prm->rbuf + i * prm->max_psize;
+		}
+
+		if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
+			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(u_audio_start_playback);
+
+void u_audio_stop_playback(struct g_audio *audio_dev)
+{
+	struct snd_uac_chip *uac = audio_dev->uac;
+
+	free_ep(&uac->p_prm, audio_dev->in_ep);
+}
+EXPORT_SYMBOL_GPL(u_audio_stop_playback);
+
+int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
+					const char *card_name)
+{
+	struct snd_uac_chip *uac;
+	struct snd_card *card;
+	struct snd_pcm *pcm;
+	struct uac_params *params;
+	int p_chmask, c_chmask;
+	int err;
+
+	if (!g_audio)
+		return -EINVAL;
+
+	uac = kzalloc(sizeof(*uac), GFP_KERNEL);
+	if (!uac)
+		return -ENOMEM;
+	g_audio->uac = uac;
+	uac->audio_dev = g_audio;
+
+	params = &g_audio->params;
+	p_chmask = params->p_chmask;
+	c_chmask = params->c_chmask;
+
+	if (c_chmask) {
+		struct uac_rtd_params *prm = &uac->c_prm;
+
+		uac->c_prm.uac = uac;
+		prm->max_psize = g_audio->out_ep_maxpsize;
+
+		prm->ureq = kcalloc(params->req_number, sizeof(struct uac_req),
+				GFP_KERNEL);
+		if (!prm->ureq) {
+			err = -ENOMEM;
+			goto fail;
+		}
+
+		prm->rbuf = kcalloc(params->req_number, prm->max_psize,
+				GFP_KERNEL);
+		if (!prm->rbuf) {
+			prm->max_psize = 0;
+			err = -ENOMEM;
+			goto fail;
+		}
+	}
+
+	if (p_chmask) {
+		struct uac_rtd_params *prm = &uac->p_prm;
+
+		uac->p_prm.uac = uac;
+		prm->max_psize = g_audio->in_ep_maxpsize;
+
+		prm->ureq = kcalloc(params->req_number, sizeof(struct uac_req),
+				GFP_KERNEL);
+		if (!prm->ureq) {
+			err = -ENOMEM;
+			goto fail;
+		}
+
+		prm->rbuf = kcalloc(params->req_number, prm->max_psize,
+				GFP_KERNEL);
+		if (!prm->rbuf) {
+			prm->max_psize = 0;
+			err = -ENOMEM;
+			goto fail;
+		}
+	}
+
+	/* Choose any slot, with no id */
+	err = snd_card_new(&g_audio->gadget->dev,
+			-1, NULL, THIS_MODULE, 0, &card);
+	if (err < 0)
+		goto fail;
+
+	uac->card = card;
+
+	/*
+	 * Create first PCM device
+	 * Create a substream only for non-zero channel streams
+	 */
+	err = snd_pcm_new(uac->card, pcm_name, 0,
+			       p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
+	if (err < 0)
+		goto snd_fail;
+
+	strcpy(pcm->name, pcm_name);
+	pcm->private_data = uac;
+	uac->pcm = pcm;
+
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac_pcm_ops);
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac_pcm_ops);
+
+	strcpy(card->driver, card_name);
+	strcpy(card->shortname, card_name);
+	sprintf(card->longname, "%s %i", card_name, card->dev->id);
+
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
+		snd_dma_continuous_data(GFP_KERNEL), 0, BUFF_SIZE_MAX);
+
+	err = snd_card_register(card);
+
+	if (!err)
+		return 0;
+
+snd_fail:
+	snd_card_free(card);
+fail:
+	kfree(uac->p_prm.ureq);
+	kfree(uac->c_prm.ureq);
+	kfree(uac->p_prm.rbuf);
+	kfree(uac->c_prm.rbuf);
+	kfree(uac);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(g_audio_setup);
+
+void g_audio_cleanup(struct g_audio *g_audio)
+{
+	struct snd_uac_chip *uac;
+	struct snd_card *card;
+
+	if (!g_audio || !g_audio->uac)
+		return;
+
+	uac = g_audio->uac;
+	card = uac->card;
+	if (card)
+		snd_card_free(card);
+
+	kfree(uac->p_prm.ureq);
+	kfree(uac->c_prm.ureq);
+	kfree(uac->p_prm.rbuf);
+	kfree(uac->c_prm.rbuf);
+	kfree(uac);
+}
+EXPORT_SYMBOL_GPL(g_audio_cleanup);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("USB gadget \"ALSA sound card\" utilities");
+MODULE_AUTHOR("Ruslan Bilovol");
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
new file mode 100644
index 000000000000..07e13784cbb8
--- /dev/null
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -0,0 +1,95 @@
+/*
+ * u_audio.h -- interface to USB gadget "ALSA sound card" utilities
+ *
+ * Copyright (C) 2016
+ * Author: Ruslan Bilovol <ruslan.bilovol@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __U_AUDIO_H
+#define __U_AUDIO_H
+
+#include <linux/usb/composite.h>
+
+struct uac_params {
+	/* playback */
+	int p_chmask;	/* channel mask */
+	int p_srate;	/* rate in Hz */
+	int p_ssize;	/* sample size */
+
+	/* capture */
+	int c_chmask;	/* channel mask */
+	int c_srate;	/* rate in Hz */
+	int c_ssize;	/* sample size */
+
+	int req_number; /* number of preallocated requests */
+};
+
+struct g_audio {
+	struct usb_function func;
+	struct usb_gadget *gadget;
+
+	struct usb_ep *in_ep;
+	struct usb_ep *out_ep;
+
+	/* Max packet size for all in_ep possible speeds */
+	unsigned int in_ep_maxpsize;
+	/* Max packet size for all out_ep possible speeds */
+	unsigned int out_ep_maxpsize;
+
+	/* The ALSA Sound Card it represents on the USB-Client side */
+	struct snd_uac_chip *uac;
+
+	struct uac_params params;
+};
+
+static inline struct g_audio *func_to_g_audio(struct usb_function *f)
+{
+	return container_of(f, struct g_audio, func);
+}
+
+static inline uint num_channels(uint chanmask)
+{
+	uint num = 0;
+
+	while (chanmask) {
+		num += (chanmask & 1);
+		chanmask >>= 1;
+	}
+
+	return num;
+}
+
+/*
+ * g_audio_setup - initialize one virtual ALSA sound card
+ * @g_audio: struct with filled params, in_ep_maxpsize, out_ep_maxpsize
+ * @pcm_name: the id string for a PCM instance of this sound card
+ * @card_name: name of this soundcard
+ *
+ * This sets up the single virtual ALSA sound card that may be exported by a
+ * gadget driver using this framework.
+ *
+ * Context: may sleep
+ *
+ * Returns zero on success, or a negative error on failure.
+ */
+int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
+					const char *card_name);
+void g_audio_cleanup(struct g_audio *g_audio);
+
+int u_audio_start_capture(struct g_audio *g_audio);
+void u_audio_stop_capture(struct g_audio *g_audio);
+int u_audio_start_playback(struct g_audio *g_audio);
+void u_audio_stop_playback(struct g_audio *g_audio);
+
+#endif /* __U_AUDIO_H */
diff --git a/drivers/usb/gadget/function/u_fs.h b/drivers/usb/gadget/function/u_fs.h
index 4378cc2fcac3..540f1c48c1a8 100644
--- a/drivers/usb/gadget/function/u_fs.h
+++ b/drivers/usb/gadget/function/u_fs.h
@@ -216,6 +216,9 @@ struct ffs_data {
 #define FFS_FL_CALL_CLOSED_CALLBACK 0
 #define FFS_FL_BOUND                1
 
+	/* For waking up blocked threads when function is enabled. */
+	wait_queue_head_t		wait;
+
 	/* Active function */
 	struct ffs_function		*func;
 
diff --git a/drivers/usb/gadget/function/u_uac1.h b/drivers/usb/gadget/function/u_uac1.h
index 5c2ac8e8456d..6f188fd8633f 100644
--- a/drivers/usb/gadget/function/u_uac1.h
+++ b/drivers/usb/gadget/function/u_uac1.h
@@ -1,82 +1,41 @@
 /*
- * u_uac1.h -- interface to USB gadget "ALSA AUDIO" utilities
+ * u_uac1.h - Utility definitions for UAC1 function
  *
- * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
- * Copyright (C) 2008 Analog Devices, Inc
+ * Copyright (C) 2016 Ruslan Bilovol <ruslan.bilovol@gmail.com>
  *
- * Enter bugs at http://blackfin.uclinux.org/
- *
- * Licensed under the GPL-2 or later.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  */
 
-#ifndef __U_AUDIO_H
-#define __U_AUDIO_H
+#ifndef __U_UAC1_H
+#define __U_UAC1_H
 
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/usb/audio.h>
 #include <linux/usb/composite.h>
 
-#include <sound/core.h>
-#include <sound/pcm.h>
-#include <sound/pcm_params.h>
-
-#define FILE_PCM_PLAYBACK	"/dev/snd/pcmC0D0p"
-#define FILE_PCM_CAPTURE	"/dev/snd/pcmC0D0c"
-#define FILE_CONTROL		"/dev/snd/controlC0"
-
 #define UAC1_OUT_EP_MAX_PACKET_SIZE	200
-#define UAC1_REQ_COUNT			256
-#define UAC1_AUDIO_BUF_SIZE		48000
-
-/*
- * This represents the USB side of an audio card device, managed by a USB
- * function which provides control and stream interfaces.
- */
-
-struct gaudio_snd_dev {
-	struct gaudio			*card;
-	struct file			*filp;
-	struct snd_pcm_substream	*substream;
-	int				access;
-	int				format;
-	int				channels;
-	int				rate;
-};
-
-struct gaudio {
-	struct usb_function		func;
-	struct usb_gadget		*gadget;
+#define UAC1_DEF_CCHMASK	0x3
+#define UAC1_DEF_CSRATE		48000
+#define UAC1_DEF_CSSIZE		2
+#define UAC1_DEF_PCHMASK	0x3
+#define UAC1_DEF_PSRATE		48000
+#define UAC1_DEF_PSSIZE		2
+#define UAC1_DEF_REQ_NUM	2
 
-	/* ALSA sound device interfaces */
-	struct gaudio_snd_dev		control;
-	struct gaudio_snd_dev		playback;
-	struct gaudio_snd_dev		capture;
-
-	/* TODO */
-};
 
 struct f_uac1_opts {
 	struct usb_function_instance	func_inst;
-	int				req_buf_size;
-	int				req_count;
-	int				audio_buf_size;
-	char				*fn_play;
-	char				*fn_cap;
-	char				*fn_cntl;
+	int				c_chmask;
+	int				c_srate;
+	int				c_ssize;
+	int				p_chmask;
+	int				p_srate;
+	int				p_ssize;
+	int				req_number;
 	unsigned			bound:1;
-	unsigned			fn_play_alloc:1;
-	unsigned			fn_cap_alloc:1;
-	unsigned			fn_cntl_alloc:1;
+
 	struct mutex			lock;
 	int				refcnt;
 };
 
-int gaudio_setup(struct gaudio *card);
-void gaudio_cleanup(struct gaudio *the_card);
-
-size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
-int u_audio_get_playback_channels(struct gaudio *card);
-int u_audio_get_playback_rate(struct gaudio *card);
-
-#endif /* __U_AUDIO_H */
+#endif /* __U_UAC1_H */
diff --git a/drivers/usb/gadget/function/u_uac1.c b/drivers/usb/gadget/function/u_uac1_legacy.c
index c78c84138a28..8aa76b4dc117 100644
--- a/drivers/usb/gadget/function/u_uac1.c
+++ b/drivers/usb/gadget/function/u_uac1_legacy.c
@@ -18,7 +18,7 @@
 #include <linux/random.h>
 #include <linux/syscalls.h>
 
-#include "u_uac1.h"
+#include "u_uac1_legacy.h"
 
 /*
  * This component encapsulates the ALSA devices for USB audio gadget
@@ -205,10 +205,11 @@ static int gaudio_open_snd_dev(struct gaudio *card)
 {
 	struct snd_pcm_file *pcm_file;
 	struct gaudio_snd_dev *snd;
-	struct f_uac1_opts *opts;
+	struct f_uac1_legacy_opts *opts;
 	char *fn_play, *fn_cap, *fn_cntl;
 
-	opts = container_of(card->func.fi, struct f_uac1_opts, func_inst);
+	opts = container_of(card->func.fi, struct f_uac1_legacy_opts,
+			    func_inst);
 	fn_play = opts->fn_play;
 	fn_cap = opts->fn_cap;
 	fn_cntl = opts->fn_cntl;
diff --git a/drivers/usb/gadget/function/u_uac1_legacy.h b/drivers/usb/gadget/function/u_uac1_legacy.h
new file mode 100644
index 000000000000..d715b1af56a4
--- /dev/null
+++ b/drivers/usb/gadget/function/u_uac1_legacy.h
@@ -0,0 +1,82 @@
+/*
+ * u_uac1.h -- interface to USB gadget "ALSA AUDIO" utilities
+ *
+ * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
+ * Copyright (C) 2008 Analog Devices, Inc
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef __U_UAC1_LEGACY_H
+#define __U_UAC1_LEGACY_H
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/composite.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#define FILE_PCM_PLAYBACK	"/dev/snd/pcmC0D0p"
+#define FILE_PCM_CAPTURE	"/dev/snd/pcmC0D0c"
+#define FILE_CONTROL		"/dev/snd/controlC0"
+
+#define UAC1_OUT_EP_MAX_PACKET_SIZE	200
+#define UAC1_REQ_COUNT			256
+#define UAC1_AUDIO_BUF_SIZE		48000
+
+/*
+ * This represents the USB side of an audio card device, managed by a USB
+ * function which provides control and stream interfaces.
+ */
+
+struct gaudio_snd_dev {
+	struct gaudio			*card;
+	struct file			*filp;
+	struct snd_pcm_substream	*substream;
+	int				access;
+	int				format;
+	int				channels;
+	int				rate;
+};
+
+struct gaudio {
+	struct usb_function		func;
+	struct usb_gadget		*gadget;
+
+	/* ALSA sound device interfaces */
+	struct gaudio_snd_dev		control;
+	struct gaudio_snd_dev		playback;
+	struct gaudio_snd_dev		capture;
+
+	/* TODO */
+};
+
+struct f_uac1_legacy_opts {
+	struct usb_function_instance	func_inst;
+	int				req_buf_size;
+	int				req_count;
+	int				audio_buf_size;
+	char				*fn_play;
+	char				*fn_cap;
+	char				*fn_cntl;
+	unsigned			bound:1;
+	unsigned			fn_play_alloc:1;
+	unsigned			fn_cap_alloc:1;
+	unsigned			fn_cntl_alloc:1;
+	struct mutex			lock;
+	int				refcnt;
+};
+
+int gaudio_setup(struct gaudio *card);
+void gaudio_cleanup(struct gaudio *the_card);
+
+size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
+int u_audio_get_playback_channels(struct gaudio *card);
+int u_audio_get_playback_rate(struct gaudio *card);
+
+#endif /* __U_UAC1_LEGACY_H */