20 files changed, 526 insertions, 86 deletions

diff --git a/drivers/usb/gadget/function/f_ecm.c b/drivers/usb/gadget/function/f_ecm.c
index 7f5cf488b2b1..ffe2486fce71 100644
--- a/drivers/usb/gadget/function/f_ecm.c
+++ b/drivers/usb/gadget/function/f_ecm.c
@@ -791,7 +791,7 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f)
 		fs_ecm_notify_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, ecm_fs_function, ecm_hs_function,
-			ecm_ss_function, NULL);
+			ecm_ss_function, ecm_ss_function);
 	if (status)
 		goto fail;
 
diff --git a/drivers/usb/gadget/function/f_eem.c b/drivers/usb/gadget/function/f_eem.c
index cfcc4e81fb77..5d38f29bda72 100644
--- a/drivers/usb/gadget/function/f_eem.c
+++ b/drivers/usb/gadget/function/f_eem.c
@@ -30,6 +30,11 @@ struct f_eem {
 	u8				ctrl_id;
 };
 
+struct in_context {
+	struct sk_buff	*skb;
+	struct usb_ep	*ep;
+};
+
 static inline struct f_eem *func_to_eem(struct usb_function *f)
 {
 	return container_of(f, struct f_eem, port.func);
@@ -302,7 +307,7 @@ static int eem_bind(struct usb_configuration *c, struct usb_function *f)
 	eem_ss_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, eem_fs_function, eem_hs_function,
-			eem_ss_function, NULL);
+			eem_ss_function, eem_ss_function);
 	if (status)
 		goto fail;
 
@@ -320,9 +325,12 @@ fail:
 
 static void eem_cmd_complete(struct usb_ep *ep, struct usb_request *req)
 {
-	struct sk_buff *skb = (struct sk_buff *)req->context;
+	struct in_context *ctx = req->context;
 
-	dev_kfree_skb_any(skb);
+	dev_kfree_skb_any(ctx->skb);
+	kfree(req->buf);
+	usb_ep_free_request(ctx->ep, req);
+	kfree(ctx);
 }
 
 /*
@@ -410,7 +418,9 @@ static int eem_unwrap(struct gether *port,
 		 * b15:		bmType (0 == data, 1 == command)
 		 */
 		if (header & BIT(15)) {
-			struct usb_request	*req = cdev->req;
+			struct usb_request	*req;
+			struct in_context	*ctx;
+			struct usb_ep		*ep;
 			u16			bmEEMCmd;
 
 			/* EEM command packet format:
@@ -439,11 +449,36 @@ static int eem_unwrap(struct gether *port,
 				skb_trim(skb2, len);
 				put_unaligned_le16(BIT(15) | BIT(11) | len,
 							skb_push(skb2, 2));
+
+				ep = port->in_ep;
+				req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+				if (!req) {
+					dev_kfree_skb_any(skb2);
+					goto next;
+				}
+
+				req->buf = kmalloc(skb2->len, GFP_KERNEL);
+				if (!req->buf) {
+					usb_ep_free_request(ep, req);
+					dev_kfree_skb_any(skb2);
+					goto next;
+				}
+
+				ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
+				if (!ctx) {
+					kfree(req->buf);
+					usb_ep_free_request(ep, req);
+					dev_kfree_skb_any(skb2);
+					goto next;
+				}
+				ctx->skb = skb2;
+				ctx->ep = ep;
+
 				skb_copy_bits(skb2, 0, req->buf, skb2->len);
 				req->length = skb2->len;
 				req->complete = eem_cmd_complete;
 				req->zero = 1;
-				req->context = skb2;
+				req->context = ctx;
 				if (usb_ep_queue(port->in_ep, req, GFP_ATOMIC))
 					DBG(cdev, "echo response queue fail\n");
 				break;
@@ -495,7 +530,7 @@ static int eem_unwrap(struct gether *port,
 			skb2 = skb_clone(skb, GFP_ATOMIC);
 			if (unlikely(!skb2)) {
 				DBG(cdev, "unable to unframe EEM packet\n");
-				continue;
+				goto next;
 			}
 			skb_trim(skb2, len - ETH_FCS_LEN);
 
@@ -505,7 +540,7 @@ static int eem_unwrap(struct gether *port,
 						GFP_ATOMIC);
 			if (unlikely(!skb3)) {
 				dev_kfree_skb_any(skb2);
-				continue;
+				goto next;
 			}
 			dev_kfree_skb_any(skb2);
 			skb_queue_tail(list, skb3);
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index bf109191659a..9c0c393abb39 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -250,8 +250,8 @@ EXPORT_SYMBOL_GPL(ffs_lock);
 static struct ffs_dev *_ffs_find_dev(const char *name);
 static struct ffs_dev *_ffs_alloc_dev(void);
 static void _ffs_free_dev(struct ffs_dev *dev);
-static void *ffs_acquire_dev(const char *dev_name);
-static void ffs_release_dev(struct ffs_data *ffs_data);
+static int ffs_acquire_dev(const char *dev_name, struct ffs_data *ffs_data);
+static void ffs_release_dev(struct ffs_dev *ffs_dev);
 static int ffs_ready(struct ffs_data *ffs);
 static void ffs_closed(struct ffs_data *ffs);
 
@@ -1554,8 +1554,8 @@ unmapped_value:
 static int ffs_fs_get_tree(struct fs_context *fc)
 {
 	struct ffs_sb_fill_data *ctx = fc->fs_private;
-	void *ffs_dev;
 	struct ffs_data	*ffs;
+	int ret;
 
 	ENTER();
 
@@ -1574,13 +1574,12 @@ static int ffs_fs_get_tree(struct fs_context *fc)
 		return -ENOMEM;
 	}
 
-	ffs_dev = ffs_acquire_dev(ffs->dev_name);
-	if (IS_ERR(ffs_dev)) {
+	ret = ffs_acquire_dev(ffs->dev_name, ffs);
+	if (ret) {
 		ffs_data_put(ffs);
-		return PTR_ERR(ffs_dev);
+		return ret;
 	}
 
-	ffs->private_data = ffs_dev;
 	ctx->ffs_data = ffs;
 	return get_tree_nodev(fc, ffs_sb_fill);
 }
@@ -1591,7 +1590,6 @@ static void ffs_fs_free_fc(struct fs_context *fc)
 
 	if (ctx) {
 		if (ctx->ffs_data) {
-			ffs_release_dev(ctx->ffs_data);
 			ffs_data_put(ctx->ffs_data);
 		}
 
@@ -1630,10 +1628,8 @@ ffs_fs_kill_sb(struct super_block *sb)
 	ENTER();
 
 	kill_litter_super(sb);
-	if (sb->s_fs_info) {
-		ffs_release_dev(sb->s_fs_info);
+	if (sb->s_fs_info)
 		ffs_data_closed(sb->s_fs_info);
-	}
 }
 
 static struct file_system_type ffs_fs_type = {
@@ -1703,6 +1699,7 @@ static void ffs_data_put(struct ffs_data *ffs)
 	if (refcount_dec_and_test(&ffs->ref)) {
 		pr_info("%s(): freeing\n", __func__);
 		ffs_data_clear(ffs);
+		ffs_release_dev(ffs->private_data);
 		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
 		       swait_active(&ffs->ep0req_completion.wait) ||
 		       waitqueue_active(&ffs->wait));
@@ -3032,6 +3029,7 @@ static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
 	struct ffs_function *func = ffs_func_from_usb(f);
 	struct f_fs_opts *ffs_opts =
 		container_of(f->fi, struct f_fs_opts, func_inst);
+	struct ffs_data *ffs_data;
 	int ret;
 
 	ENTER();
@@ -3046,12 +3044,13 @@ static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
 	if (!ffs_opts->no_configfs)
 		ffs_dev_lock();
 	ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
-	func->ffs = ffs_opts->dev->ffs_data;
+	ffs_data = ffs_opts->dev->ffs_data;
 	if (!ffs_opts->no_configfs)
 		ffs_dev_unlock();
 	if (ret)
 		return ERR_PTR(ret);
 
+	func->ffs = ffs_data;
 	func->conf = c;
 	func->gadget = c->cdev->gadget;
 
@@ -3506,6 +3505,7 @@ static void ffs_free_inst(struct usb_function_instance *f)
 	struct f_fs_opts *opts;
 
 	opts = to_f_fs_opts(f);
+	ffs_release_dev(opts->dev);
 	ffs_dev_lock();
 	_ffs_free_dev(opts->dev);
 	ffs_dev_unlock();
@@ -3567,6 +3567,9 @@ static void ffs_func_unbind(struct usb_configuration *c,
 		ffs->func = NULL;
 	}
 
+	/* Drain any pending AIO completions */
+	drain_workqueue(ffs->io_completion_wq);
+
 	if (!--opts->refcnt)
 		functionfs_unbind(ffs);
 
@@ -3690,47 +3693,48 @@ static void _ffs_free_dev(struct ffs_dev *dev)
 {
 	list_del(&dev->entry);
 
-	/* Clear the private_data pointer to stop incorrect dev access */
-	if (dev->ffs_data)
-		dev->ffs_data->private_data = NULL;
-
 	kfree(dev);
 	if (list_empty(&ffs_devices))
 		functionfs_cleanup();
 }
 
-static void *ffs_acquire_dev(const char *dev_name)
+static int ffs_acquire_dev(const char *dev_name, struct ffs_data *ffs_data)
 {
+	int ret = 0;
 	struct ffs_dev *ffs_dev;
 
 	ENTER();
 	ffs_dev_lock();
 
 	ffs_dev = _ffs_find_dev(dev_name);
-	if (!ffs_dev)
-		ffs_dev = ERR_PTR(-ENOENT);
-	else if (ffs_dev->mounted)
-		ffs_dev = ERR_PTR(-EBUSY);
-	else if (ffs_dev->ffs_acquire_dev_callback &&
-	    ffs_dev->ffs_acquire_dev_callback(ffs_dev))
-		ffs_dev = ERR_PTR(-ENOENT);
-	else
+	if (!ffs_dev) {
+		ret = -ENOENT;
+	} else if (ffs_dev->mounted) {
+		ret = -EBUSY;
+	} else if (ffs_dev->ffs_acquire_dev_callback &&
+		   ffs_dev->ffs_acquire_dev_callback(ffs_dev)) {
+		ret = -ENOENT;
+	} else {
 		ffs_dev->mounted = true;
+		ffs_dev->ffs_data = ffs_data;
+		ffs_data->private_data = ffs_dev;
+	}
 
 	ffs_dev_unlock();
-	return ffs_dev;
+	return ret;
 }
 
-static void ffs_release_dev(struct ffs_data *ffs_data)
+static void ffs_release_dev(struct ffs_dev *ffs_dev)
 {
-	struct ffs_dev *ffs_dev;
-
 	ENTER();
 	ffs_dev_lock();
 
-	ffs_dev = ffs_data->private_data;
-	if (ffs_dev) {
+	if (ffs_dev && ffs_dev->mounted) {
 		ffs_dev->mounted = false;
+		if (ffs_dev->ffs_data) {
+			ffs_dev->ffs_data->private_data = NULL;
+			ffs_dev->ffs_data = NULL;
+		}
 
 		if (ffs_dev->ffs_release_dev_callback)
 			ffs_dev->ffs_release_dev_callback(ffs_dev);
@@ -3758,7 +3762,6 @@ static int ffs_ready(struct ffs_data *ffs)
 	}
 
 	ffs_obj->desc_ready = true;
-	ffs_obj->ffs_data = ffs;
 
 	if (ffs_obj->ffs_ready_callback) {
 		ret = ffs_obj->ffs_ready_callback(ffs);
@@ -3786,7 +3789,6 @@ static void ffs_closed(struct ffs_data *ffs)
 		goto done;
 
 	ffs_obj->desc_ready = false;
-	ffs_obj->ffs_data = NULL;
 
 	if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags) &&
 	    ffs_obj->ffs_closed_callback)
diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index 1125f4715830..bb476e121eae 100644
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/drivers/usb/gadget/function/f_hid.c
@@ -41,6 +41,7 @@ struct f_hidg {
 	unsigned char			bInterfaceSubClass;
 	unsigned char			bInterfaceProtocol;
 	unsigned char			protocol;
+	unsigned char			idle;
 	unsigned short			report_desc_length;
 	char				*report_desc;
 	unsigned short			report_length;
@@ -88,7 +89,7 @@ static struct usb_interface_descriptor hidg_interface_desc = {
 static struct hid_descriptor hidg_desc = {
 	.bLength			= sizeof hidg_desc,
 	.bDescriptorType		= HID_DT_HID,
-	.bcdHID				= 0x0101,
+	.bcdHID				= cpu_to_le16(0x0101),
 	.bCountryCode			= 0x00,
 	.bNumDescriptors		= 0x1,
 	/*.desc[0].bDescriptorType	= DYNAMIC */
@@ -338,6 +339,11 @@ static ssize_t f_hidg_write(struct file *file, const char __user *buffer,
 
 	spin_lock_irqsave(&hidg->write_spinlock, flags);
 
+	if (!hidg->req) {
+		spin_unlock_irqrestore(&hidg->write_spinlock, flags);
+		return -ESHUTDOWN;
+	}
+
 #define WRITE_COND (!hidg->write_pending)
 try_again:
 	/* write queue */
@@ -358,8 +364,14 @@ try_again:
 	count  = min_t(unsigned, count, hidg->report_length);
 
 	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
-	status = copy_from_user(req->buf, buffer, count);
 
+	if (!req) {
+		ERROR(hidg->func.config->cdev, "hidg->req is NULL\n");
+		status = -ESHUTDOWN;
+		goto release_write_pending;
+	}
+
+	status = copy_from_user(req->buf, buffer, count);
 	if (status != 0) {
 		ERROR(hidg->func.config->cdev,
 			"copy_from_user error\n");
@@ -387,14 +399,17 @@ try_again:
 
 	spin_unlock_irqrestore(&hidg->write_spinlock, flags);
 
+	if (!hidg->in_ep->enabled) {
+		ERROR(hidg->func.config->cdev, "in_ep is disabled\n");
+		status = -ESHUTDOWN;
+		goto release_write_pending;
+	}
+
 	status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC);
-	if (status < 0) {
-		ERROR(hidg->func.config->cdev,
-			"usb_ep_queue error on int endpoint %zd\n", status);
+	if (status < 0)
 		goto release_write_pending;
-	} else {
+	else
 		status = count;
-	}
 
 	return status;
 release_write_pending:
@@ -523,6 +538,14 @@ static int hidg_setup(struct usb_function *f,
 		goto respond;
 		break;
 
+	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+		  | HID_REQ_GET_IDLE):
+		VDBG(cdev, "get_idle\n");
+		length = min_t(unsigned int, length, 1);
+		((u8 *) req->buf)[0] = hidg->idle;
+		goto respond;
+		break;
+
 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
 		  | HID_REQ_SET_REPORT):
 		VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength);
@@ -546,6 +569,14 @@ static int hidg_setup(struct usb_function *f,
 		goto stall;
 		break;
 
+	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8
+		  | HID_REQ_SET_IDLE):
+		VDBG(cdev, "set_idle\n");
+		length = 0;
+		hidg->idle = value >> 8;
+		goto respond;
+		break;
+
 	case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
 		  | USB_REQ_GET_DESCRIPTOR):
 		switch (value >> 8) {
@@ -773,6 +804,7 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass;
 	hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol;
 	hidg->protocol = HID_REPORT_PROTOCOL;
+	hidg->idle = 1;
 	hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length);
 	hidg_ss_in_comp_desc.wBytesPerInterval =
 				cpu_to_le16(hidg->report_length);
@@ -802,7 +834,8 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f)
 		hidg_fs_out_ep_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, hidg_fs_descriptors,
-			hidg_hs_descriptors, hidg_ss_descriptors, NULL);
+			hidg_hs_descriptors, hidg_ss_descriptors,
+			hidg_ss_descriptors);
 	if (status)
 		goto fail;
 
@@ -1117,7 +1150,7 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
 	hidg->func.setup   = hidg_setup;
 	hidg->func.free_func = hidg_free;
 
-	/* this could me made configurable at some point */
+	/* this could be made configurable at some point */
 	hidg->qlen	   = 4;
 
 	return &hidg->func;
diff --git a/drivers/usb/gadget/function/f_loopback.c b/drivers/usb/gadget/function/f_loopback.c
index b56ad7c3838b..ae41f556eb75 100644
--- a/drivers/usb/gadget/function/f_loopback.c
+++ b/drivers/usb/gadget/function/f_loopback.c
@@ -207,7 +207,7 @@ autoconf_fail:
 	ss_loop_sink_desc.bEndpointAddress = fs_loop_sink_desc.bEndpointAddress;
 
 	ret = usb_assign_descriptors(f, fs_loopback_descs, hs_loopback_descs,
-			ss_loopback_descs, NULL);
+			ss_loopback_descs, ss_loopback_descs);
 	if (ret)
 		return ret;
 
diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c
index 019bea8e09cc..855127249f24 100644
--- a/drivers/usb/gadget/function/f_ncm.c
+++ b/drivers/usb/gadget/function/f_ncm.c
@@ -583,7 +583,7 @@ static void ncm_do_notify(struct f_ncm *ncm)
 		data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
 		data[1] = data[0];
 
-		DBG(cdev, "notify speed %d\n", ncm_bitrate(cdev->gadget));
+		DBG(cdev, "notify speed %u\n", ncm_bitrate(cdev->gadget));
 		ncm->notify_state = NCM_NOTIFY_CONNECT;
 		break;
 	}
@@ -1101,11 +1101,11 @@ static struct sk_buff *ncm_wrap_ntb(struct gether *port,
 			ncm->ndp_dgram_count = 1;
 
 			/* Note: we skip opts->next_ndp_index */
-		}
 
-		/* Delay the timer. */
-		hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
-			      HRTIMER_MODE_REL_SOFT);
+			/* Start the timer. */
+			hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
+				      HRTIMER_MODE_REL_SOFT);
+		}
 
 		/* Add the datagram position entries */
 		ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c
index f47fdc1fa7f1..abec5c58f525 100644
--- a/drivers/usb/gadget/function/f_printer.c
+++ b/drivers/usb/gadget/function/f_printer.c
@@ -667,8 +667,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 		value = usb_ep_queue(dev->in_ep, req, GFP_ATOMIC);
 		spin_lock(&dev->lock);
 		if (value) {
-			list_del(&req->list);
-			list_add(&req->list, &dev->tx_reqs);
+			list_move(&req->list, &dev->tx_reqs);
 			spin_unlock_irqrestore(&dev->lock, flags);
 			mutex_unlock(&dev->lock_printer_io);
 			return -EAGAIN;
@@ -1101,7 +1100,8 @@ autoconf_fail:
 	ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
 
 	ret = usb_assign_descriptors(f, fs_printer_function,
-			hs_printer_function, ss_printer_function, NULL);
+			hs_printer_function, ss_printer_function,
+			ss_printer_function);
 	if (ret)
 		return ret;
 
diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index 0739b05a0ef7..ee95e8f5f9d4 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -789,7 +789,7 @@ rndis_bind(struct usb_configuration *c, struct usb_function *f)
 	ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function,
-			eth_ss_function, NULL);
+			eth_ss_function, eth_ss_function);
 	if (status)
 		goto fail;
 
diff --git a/drivers/usb/gadget/function/f_serial.c b/drivers/usb/gadget/function/f_serial.c
index e62713846350..1ed8ff0ac2d3 100644
--- a/drivers/usb/gadget/function/f_serial.c
+++ b/drivers/usb/gadget/function/f_serial.c
@@ -233,7 +233,7 @@ static int gser_bind(struct usb_configuration *c, struct usb_function *f)
 	gser_ss_out_desc.bEndpointAddress = gser_fs_out_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, gser_fs_function, gser_hs_function,
-			gser_ss_function, NULL);
+			gser_ss_function, gser_ss_function);
 	if (status)
 		goto fail;
 	dev_dbg(&cdev->gadget->dev, "generic ttyGS%d: %s speed IN/%s OUT/%s\n",
diff --git a/drivers/usb/gadget/function/f_sourcesink.c b/drivers/usb/gadget/function/f_sourcesink.c
index 5a201ba7b155..1abf08e5164a 100644
--- a/drivers/usb/gadget/function/f_sourcesink.c
+++ b/drivers/usb/gadget/function/f_sourcesink.c
@@ -431,7 +431,8 @@ no_iso:
 	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
 
 	ret = usb_assign_descriptors(f, fs_source_sink_descs,
-			hs_source_sink_descs, ss_source_sink_descs, NULL);
+			hs_source_sink_descs, ss_source_sink_descs,
+			ss_source_sink_descs);
 	if (ret)
 		return ret;
 
diff --git a/drivers/usb/gadget/function/f_subset.c b/drivers/usb/gadget/function/f_subset.c
index 4d945254905d..51c1cae162d9 100644
--- a/drivers/usb/gadget/function/f_subset.c
+++ b/drivers/usb/gadget/function/f_subset.c
@@ -358,7 +358,7 @@ geth_bind(struct usb_configuration *c, struct usb_function *f)
 		fs_subset_out_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, fs_eth_function, hs_eth_function,
-			ss_eth_function, NULL);
+			ss_eth_function, ss_eth_function);
 	if (status)
 		goto fail;
 
diff --git a/drivers/usb/gadget/function/f_tcm.c b/drivers/usb/gadget/function/f_tcm.c
index 7acb507946e6..de161ee0b1f9 100644
--- a/drivers/usb/gadget/function/f_tcm.c
+++ b/drivers/usb/gadget/function/f_tcm.c
@@ -2057,7 +2057,8 @@ static int tcm_bind(struct usb_configuration *c, struct usb_function *f)
 	uasp_fs_cmd_desc.bEndpointAddress = uasp_ss_cmd_desc.bEndpointAddress;
 
 	ret = usb_assign_descriptors(f, uasp_fs_function_desc,
-			uasp_hs_function_desc, uasp_ss_function_desc, NULL);
+			uasp_hs_function_desc, uasp_ss_function_desc,
+			uasp_ss_function_desc);
 	if (ret)
 		goto ep_fail;
 
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 7aa4c8bc5a1a..ae29ff2b2b68 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -44,6 +44,7 @@
 
 #define EPIN_EN(_opts) ((_opts)->p_chmask != 0)
 #define EPOUT_EN(_opts) ((_opts)->c_chmask != 0)
+#define EPOUT_FBACK_IN_EN(_opts) ((_opts)->c_sync == USB_ENDPOINT_SYNC_ASYNC)
 
 struct f_uac2 {
 	struct g_audio g_audio;
@@ -273,7 +274,7 @@ static struct usb_endpoint_descriptor fs_epout_desc = {
 	.bDescriptorType = USB_DT_ENDPOINT,
 
 	.bEndpointAddress = USB_DIR_OUT,
-	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
+	/* .bmAttributes = DYNAMIC */
 	/* .wMaxPacketSize = DYNAMIC */
 	.bInterval = 1,
 };
@@ -282,7 +283,7 @@ static struct usb_endpoint_descriptor hs_epout_desc = {
 	.bLength = USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType = USB_DT_ENDPOINT,
 
-	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
+	/* .bmAttributes = DYNAMIC */
 	/* .wMaxPacketSize = DYNAMIC */
 	.bInterval = 4,
 };
@@ -292,7 +293,7 @@ static struct usb_endpoint_descriptor ss_epout_desc = {
 	.bDescriptorType = USB_DT_ENDPOINT,
 
 	.bEndpointAddress = USB_DIR_OUT,
-	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
+	/* .bmAttributes = DYNAMIC */
 	/* .wMaxPacketSize = DYNAMIC */
 	.bInterval = 4,
 };
@@ -317,6 +318,37 @@ static struct uac2_iso_endpoint_descriptor as_iso_out_desc = {
 	.wLockDelay = 0,
 };
 
+/* STD AS ISO IN Feedback Endpoint */
+static struct usb_endpoint_descriptor fs_epin_fback_desc = {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+
+	.bEndpointAddress = USB_DIR_IN,
+	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+	.wMaxPacketSize = cpu_to_le16(3),
+	.bInterval = 1,
+};
+
+static struct usb_endpoint_descriptor hs_epin_fback_desc = {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+
+	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+	.wMaxPacketSize = cpu_to_le16(4),
+	.bInterval = 4,
+};
+
+static struct usb_endpoint_descriptor ss_epin_fback_desc = {
+	.bLength = USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType = USB_DT_ENDPOINT,
+
+	.bEndpointAddress = USB_DIR_IN,
+	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+	.wMaxPacketSize = cpu_to_le16(4),
+	.bInterval = 4,
+};
+
+
 /* Audio Streaming IN Interface - Alt0 */
 static struct usb_interface_descriptor std_as_in_if0_desc = {
 	.bLength = sizeof std_as_in_if0_desc,
@@ -431,6 +463,7 @@ static struct usb_descriptor_header *fs_audio_desc[] = {
 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
 	(struct usb_descriptor_header *)&fs_epout_desc,
 	(struct usb_descriptor_header *)&as_iso_out_desc,
+	(struct usb_descriptor_header *)&fs_epin_fback_desc,
 
 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -461,6 +494,7 @@ static struct usb_descriptor_header *hs_audio_desc[] = {
 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
 	(struct usb_descriptor_header *)&hs_epout_desc,
 	(struct usb_descriptor_header *)&as_iso_out_desc,
+	(struct usb_descriptor_header *)&hs_epin_fback_desc,
 
 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -492,6 +526,7 @@ static struct usb_descriptor_header *ss_audio_desc[] = {
 	(struct usb_descriptor_header *)&ss_epout_desc,
 	(struct usb_descriptor_header *)&ss_epout_desc_comp,
 	(struct usb_descriptor_header *)&as_iso_out_desc,
+	(struct usb_descriptor_header *)&ss_epin_fback_desc,
 
 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -549,8 +584,11 @@ static int set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
 		ssize = uac2_opts->c_ssize;
 	}
 
+	if (!is_playback && (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC))
+		srate = srate * (1000 + uac2_opts->fb_max) / 1000;
+
 	max_size_bw = num_channels(chmask) * ssize *
-		((srate / (factor / (1 << (ep_desc->bInterval - 1)))) + 1);
+		DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1)));
 	ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw,
 						    max_size_ep));
 
@@ -568,22 +606,26 @@ static void setup_headers(struct f_uac2_opts *opts,
 	struct usb_ss_ep_comp_descriptor *epin_desc_comp = NULL;
 	struct usb_endpoint_descriptor *epout_desc;
 	struct usb_endpoint_descriptor *epin_desc;
+	struct usb_endpoint_descriptor *epin_fback_desc;
 	int i;
 
 	switch (speed) {
 	case USB_SPEED_FULL:
 		epout_desc = &fs_epout_desc;
 		epin_desc = &fs_epin_desc;
+		epin_fback_desc = &fs_epin_fback_desc;
 		break;
 	case USB_SPEED_HIGH:
 		epout_desc = &hs_epout_desc;
 		epin_desc = &hs_epin_desc;
+		epin_fback_desc = &hs_epin_fback_desc;
 		break;
 	default:
 		epout_desc = &ss_epout_desc;
 		epin_desc = &ss_epin_desc;
 		epout_desc_comp = &ss_epout_desc_comp;
 		epin_desc_comp = &ss_epin_desc_comp;
+		epin_fback_desc = &ss_epin_fback_desc;
 	}
 
 	i = 0;
@@ -611,6 +653,9 @@ static void setup_headers(struct f_uac2_opts *opts,
 			headers[i++] = USBDHDR(epout_desc_comp);
 
 		headers[i++] = USBDHDR(&as_iso_out_desc);
+
+		if (EPOUT_FBACK_IN_EN(opts))
+			headers[i++] = USBDHDR(epin_fback_desc);
 	}
 	if (EPIN_EN(opts)) {
 		headers[i++] = USBDHDR(&std_as_in_if0_desc);
@@ -781,6 +826,23 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		std_as_out_if1_desc.bInterfaceNumber = ret;
 		uac2->as_out_intf = ret;
 		uac2->as_out_alt = 0;
+
+		if (EPOUT_FBACK_IN_EN(uac2_opts)) {
+			fs_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
+			hs_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
+			ss_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
+			std_as_out_if1_desc.bNumEndpoints++;
+		} else {
+			fs_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
+			hs_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
+			ss_epout_desc.bmAttributes =
+			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
+		}
 	}
 
 	if (EPIN_EN(uac2_opts)) {
@@ -844,6 +906,15 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 			return -ENODEV;
 		}
+		if (EPOUT_FBACK_IN_EN(uac2_opts)) {
+			agdev->in_ep_fback = usb_ep_autoconfig(gadget,
+						       &fs_epin_fback_desc);
+			if (!agdev->in_ep_fback) {
+				dev_err(dev, "%s:%d Error!\n",
+					__func__, __LINE__);
+				return -ENODEV;
+			}
+		}
 	}
 
 	if (EPIN_EN(uac2_opts)) {
@@ -867,8 +938,10 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 				le16_to_cpu(ss_epout_desc.wMaxPacketSize));
 
 	hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
+	hs_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
 	hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
 	ss_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
+	ss_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
 	ss_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
 
 	setup_descriptor(uac2_opts);
@@ -887,6 +960,7 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	agdev->params.c_srate = uac2_opts->c_srate;
 	agdev->params.c_ssize = uac2_opts->c_ssize;
 	agdev->params.req_number = uac2_opts->req_number;
+	agdev->params.fb_max = uac2_opts->fb_max;
 	ret = g_audio_setup(agdev, "UAC2 PCM", "UAC2_Gadget");
 	if (ret)
 		goto err_free_descs;
@@ -1195,13 +1269,71 @@ end:									\
 									\
 CONFIGFS_ATTR(f_uac2_opts_, name)
 
+#define UAC2_ATTRIBUTE_SYNC(name)					\
+static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
+					 char *page)			\
+{									\
+	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
+	int result;							\
+	char *str;							\
+									\
+	mutex_lock(&opts->lock);					\
+	switch (opts->name) {						\
+	case USB_ENDPOINT_SYNC_ASYNC:					\
+		str = "async";						\
+		break;							\
+	case USB_ENDPOINT_SYNC_ADAPTIVE:				\
+		str = "adaptive";					\
+		break;							\
+	default:							\
+		str = "unknown";					\
+		break;							\
+	}								\
+	result = sprintf(page, "%s\n", str);				\
+	mutex_unlock(&opts->lock);					\
+									\
+	return result;							\
+}									\
+									\
+static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
+					  const char *page, size_t len)	\
+{									\
+	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
+	int ret = 0;							\
+									\
+	mutex_lock(&opts->lock);					\
+	if (opts->refcnt) {						\
+		ret = -EBUSY;						\
+		goto end;						\
+	}								\
+									\
+	if (!strncmp(page, "async", 5))					\
+		opts->name = USB_ENDPOINT_SYNC_ASYNC;			\
+	else if (!strncmp(page, "adaptive", 8))				\
+		opts->name = USB_ENDPOINT_SYNC_ADAPTIVE;		\
+	else {								\
+		ret = -EINVAL;						\
+		goto end;						\
+	}								\
+									\
+	ret = len;							\
+									\
+end:									\
+	mutex_unlock(&opts->lock);					\
+	return ret;							\
+}									\
+									\
+CONFIGFS_ATTR(f_uac2_opts_, name)
+
 UAC2_ATTRIBUTE(p_chmask);
 UAC2_ATTRIBUTE(p_srate);
 UAC2_ATTRIBUTE(p_ssize);
 UAC2_ATTRIBUTE(c_chmask);
 UAC2_ATTRIBUTE(c_srate);
+UAC2_ATTRIBUTE_SYNC(c_sync);
 UAC2_ATTRIBUTE(c_ssize);
 UAC2_ATTRIBUTE(req_number);
+UAC2_ATTRIBUTE(fb_max);
 
 static struct configfs_attribute *f_uac2_attrs[] = {
 	&f_uac2_opts_attr_p_chmask,
@@ -1210,7 +1342,9 @@ static struct configfs_attribute *f_uac2_attrs[] = {
 	&f_uac2_opts_attr_c_chmask,
 	&f_uac2_opts_attr_c_srate,
 	&f_uac2_opts_attr_c_ssize,
+	&f_uac2_opts_attr_c_sync,
 	&f_uac2_opts_attr_req_number,
+	&f_uac2_opts_attr_fb_max,
 	NULL,
 };
 
@@ -1248,7 +1382,9 @@ static struct usb_function_instance *afunc_alloc_inst(void)
 	opts->c_chmask = UAC2_DEF_CCHMASK;
 	opts->c_srate = UAC2_DEF_CSRATE;
 	opts->c_ssize = UAC2_DEF_CSSIZE;
+	opts->c_sync = UAC2_DEF_CSYNC;
 	opts->req_number = UAC2_DEF_REQ_NUM;
+	opts->fb_max = UAC2_DEF_FB_MAX;
 	return &opts->func_inst;
 }
 
diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index 5fbceee897a3..018dd0978995 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -16,6 +16,7 @@
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
+#include <sound/control.h>
 
 #include "u_audio.h"
 
@@ -35,9 +36,13 @@ struct uac_rtd_params {
 
 	void *rbuf;
 
+	unsigned int pitch;	/* Stream pitch ratio to 1000000 */
 	unsigned int max_psize;	/* MaxPacketSize of endpoint */
 
 	struct usb_request **reqs;
+
+	struct usb_request *req_fback; /* Feedback endpoint request */
+	bool fb_ep_enabled; /* if the ep is enabled */
 };
 
 struct snd_uac_chip {
@@ -70,6 +75,48 @@ static const struct snd_pcm_hardware uac_pcm_hardware = {
 	.periods_min = MIN_PERIODS,
 };
 
+static void u_audio_set_fback_frequency(enum usb_device_speed speed,
+					unsigned long long freq,
+					unsigned int pitch,
+					void *buf)
+{
+	u32 ff = 0;
+
+	/*
+	 * Because the pitch base is 1000000, the final divider here
+	 * will be 1000 * 1000000 = 1953125 << 9
+	 *
+	 * Instead of dealing with big numbers lets fold this 9 left shift
+	 */
+
+	if (speed == USB_SPEED_FULL) {
+		/*
+		 * Full-speed feedback endpoints report frequency
+		 * in samples/frame
+		 * Format is encoded in Q10.10 left-justified in the 24 bits,
+		 * so that it has a Q10.14 format.
+		 *
+		 * ff = (freq << 14) / 1000
+		 */
+		freq <<= 5;
+	} else {
+		/*
+		 * High-speed feedback endpoints report frequency
+		 * in samples/microframe.
+		 * Format is encoded in Q12.13 fitted into four bytes so that
+		 * the binary point is located between the second and the third
+		 * byte fromat (that is Q16.16)
+		 *
+		 * ff = (freq << 16) / 8000
+		 */
+		freq <<= 4;
+	}
+
+	ff = DIV_ROUND_CLOSEST_ULL((freq * pitch), 1953125);
+
+	*(__le32 *)buf = cpu_to_le32(ff);
+}
+
 static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 {
 	unsigned int pending;
@@ -173,6 +220,35 @@ exit:
 		dev_err(uac->card->dev, "%d Error!\n", __LINE__);
 }
 
+static void u_audio_iso_fback_complete(struct usb_ep *ep,
+				       struct usb_request *req)
+{
+	struct uac_rtd_params *prm = req->context;
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev = uac->audio_dev;
+	struct uac_params *params = &audio_dev->params;
+	int status = req->status;
+
+	/* i/f shutting down */
+	if (!prm->fb_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);
+
+	u_audio_set_fback_frequency(audio_dev->gadget->speed,
+				    params->c_srate, prm->pitch,
+				    req->buf);
+
+	if (usb_ep_queue(ep, req, GFP_ATOMIC))
+		dev_err(uac->card->dev, "%d Error!\n", __LINE__);
+}
+
 static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 {
 	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
@@ -335,14 +411,33 @@ static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
 		dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
 }
 
+static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
+{
+	struct snd_uac_chip *uac = prm->uac;
+
+	if (!prm->fb_ep_enabled)
+		return;
+
+	prm->fb_ep_enabled = false;
+
+	if (prm->req_fback) {
+		usb_ep_dequeue(ep, prm->req_fback);
+		kfree(prm->req_fback->buf);
+		usb_ep_free_request(ep, prm->req_fback);
+		prm->req_fback = 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 usb_request *req, *req_fback;
+	struct usb_ep *ep, *ep_fback;
 	struct uac_rtd_params *prm;
 	struct uac_params *params = &audio_dev->params;
 	int req_len, i;
@@ -374,6 +469,43 @@ int u_audio_start_capture(struct g_audio *audio_dev)
 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 	}
 
+	ep_fback = audio_dev->in_ep_fback;
+	if (!ep_fback)
+		return 0;
+
+	/* Setup feedback endpoint */
+	config_ep_by_speed(gadget, &audio_dev->func, ep_fback);
+	prm->fb_ep_enabled = true;
+	usb_ep_enable(ep_fback);
+	req_len = ep_fback->maxpacket;
+
+	req_fback = usb_ep_alloc_request(ep_fback, GFP_ATOMIC);
+	if (req_fback == NULL)
+		return -ENOMEM;
+
+	prm->req_fback = req_fback;
+	req_fback->zero = 0;
+	req_fback->context = prm;
+	req_fback->length = req_len;
+	req_fback->complete = u_audio_iso_fback_complete;
+
+	req_fback->buf = kzalloc(req_len, GFP_ATOMIC);
+	if (!req_fback->buf)
+		return -ENOMEM;
+
+	/*
+	 * Configure the feedback endpoint's reported frequency.
+	 * Always start with original frequency since its deviation can't
+	 * be meauserd at start of playback
+	 */
+	prm->pitch = 1000000;
+	u_audio_set_fback_frequency(audio_dev->gadget->speed,
+				    params->c_srate, prm->pitch,
+				    req_fback->buf);
+
+	if (usb_ep_queue(ep_fback, req_fback, GFP_ATOMIC))
+		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(u_audio_start_capture);
@@ -382,6 +514,8 @@ void u_audio_stop_capture(struct g_audio *audio_dev)
 {
 	struct snd_uac_chip *uac = audio_dev->uac;
 
+	if (audio_dev->in_ep_fback)
+		free_ep_fback(&uac->c_prm, audio_dev->in_ep_fback);
 	free_ep(&uac->c_prm, audio_dev->out_ep);
 }
 EXPORT_SYMBOL_GPL(u_audio_stop_capture);
@@ -463,12 +597,82 @@ void u_audio_stop_playback(struct g_audio *audio_dev)
 }
 EXPORT_SYMBOL_GPL(u_audio_stop_playback);
 
+static int u_audio_pitch_info(struct snd_kcontrol *kcontrol,
+				   struct snd_ctl_elem_info *uinfo)
+{
+	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev = uac->audio_dev;
+	struct uac_params *params = &audio_dev->params;
+	unsigned int pitch_min, pitch_max;
+
+	pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
+	pitch_max = (1000 + params->fb_max) * 1000;
+
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+	uinfo->value.integer.min = pitch_min;
+	uinfo->value.integer.max = pitch_max;
+	uinfo->value.integer.step = 1;
+	return 0;
+}
+
+static int u_audio_pitch_get(struct snd_kcontrol *kcontrol,
+				   struct snd_ctl_elem_value *ucontrol)
+{
+	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
+
+	ucontrol->value.integer.value[0] = prm->pitch;
+
+	return 0;
+}
+
+static int u_audio_pitch_put(struct snd_kcontrol *kcontrol,
+				  struct snd_ctl_elem_value *ucontrol)
+{
+	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
+	struct snd_uac_chip *uac = prm->uac;
+	struct g_audio *audio_dev = uac->audio_dev;
+	struct uac_params *params = &audio_dev->params;
+	unsigned int val;
+	unsigned int pitch_min, pitch_max;
+	int change = 0;
+
+	pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
+	pitch_max = (1000 + params->fb_max) * 1000;
+
+	val = ucontrol->value.integer.value[0];
+
+	if (val < pitch_min)
+		val = pitch_min;
+	if (val > pitch_max)
+		val = pitch_max;
+
+	if (prm->pitch != val) {
+		prm->pitch = val;
+		change = 1;
+	}
+
+	return change;
+}
+
+static const struct snd_kcontrol_new u_audio_controls[]  = {
+{
+	.iface =        SNDRV_CTL_ELEM_IFACE_PCM,
+	.name =         "Capture Pitch 1000000",
+	.info =         u_audio_pitch_info,
+	.get =          u_audio_pitch_get,
+	.put =          u_audio_pitch_put,
+},
+};
+
 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 snd_kcontrol *kctl;
 	struct uac_params *params;
 	int p_chmask, c_chmask;
 	int err;
@@ -556,6 +760,23 @@ int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac_pcm_ops);
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac_pcm_ops);
 
+	if (c_chmask && g_audio->in_ep_fback) {
+		strscpy(card->mixername, card_name, sizeof(card->driver));
+
+		kctl = snd_ctl_new1(&u_audio_controls[0], &uac->c_prm);
+		if (!kctl) {
+			err = -ENOMEM;
+			goto snd_fail;
+		}
+
+		kctl->id.device = pcm->device;
+		kctl->id.subdevice = 0;
+
+		err = snd_ctl_add(card, kctl);
+		if (err < 0)
+			goto snd_fail;
+	}
+
 	strscpy(card->driver, card_name, sizeof(card->driver));
 	strscpy(card->shortname, card_name, sizeof(card->shortname));
 	sprintf(card->longname, "%s %i", card_name, card->dev->id);
diff --git a/drivers/usb/gadget/function/u_audio.h b/drivers/usb/gadget/function/u_audio.h
index 5ea6b86f1fda..a218cdf771fe 100644
--- a/drivers/usb/gadget/function/u_audio.h
+++ b/drivers/usb/gadget/function/u_audio.h
@@ -11,6 +11,14 @@
 
 #include <linux/usb/composite.h>
 
+/*
+ * Same maximum frequency deviation on the slower side as in
+ * sound/usb/endpoint.c. Value is expressed in per-mil deviation.
+ * The maximum deviation on the faster side will be provided as
+ * parameter, as it impacts the endpoint required bandwidth.
+ */
+#define FBACK_SLOW_MAX	250
+
 struct uac_params {
 	/* playback */
 	int p_chmask;	/* channel mask */
@@ -23,6 +31,7 @@ struct uac_params {
 	int c_ssize;	/* sample size */
 
 	int req_number; /* number of preallocated requests */
+	int fb_max;	/* upper frequency drift feedback limit per-mil */
 };
 
 struct g_audio {
@@ -30,7 +39,10 @@ struct g_audio {
 	struct usb_gadget *gadget;
 
 	struct usb_ep *in_ep;
+
 	struct usb_ep *out_ep;
+	/* feedback IN endpoint corresponding to out_ep */
+	struct usb_ep *in_ep_fback;
 
 	/* Max packet size for all in_ep possible speeds */
 	unsigned int in_ep_maxpsize;
diff --git a/drivers/usb/gadget/function/u_hid.h b/drivers/usb/gadget/function/u_hid.h
index 84e6da302499..98d6af558c03 100644
--- a/drivers/usb/gadget/function/u_hid.h
+++ b/drivers/usb/gadget/function/u_hid.h
@@ -29,8 +29,8 @@ struct f_hid_opts {
 	 * Protect the data form concurrent access by read/write
 	 * and create symlink/remove symlink.
 	 */
-	 struct mutex			lock;
-	 int				refcnt;
+	struct mutex			lock;
+	int				refcnt;
 };
 
 int ghid_setup(struct usb_gadget *g, int count);
diff --git a/drivers/usb/gadget/function/u_midi.h b/drivers/usb/gadget/function/u_midi.h
index f6e14af7f566..2e400b495cb8 100644
--- a/drivers/usb/gadget/function/u_midi.h
+++ b/drivers/usb/gadget/function/u_midi.h
@@ -29,8 +29,8 @@ struct f_midi_opts {
 	 * Protect the data form concurrent access by read/write
 	 * and create symlink/remove symlink.
 	 */
-	 struct mutex			lock;
-	 int				refcnt;
+	struct mutex			lock;
+	int				refcnt;
 };
 
 #endif /* U_MIDI_H */
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index 1e59204ec7aa..281ca766698a 100644
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -774,34 +774,34 @@ static void gs_flush_chars(struct tty_struct *tty)
 	spin_unlock_irqrestore(&port->port_lock, flags);
 }
 
-static int gs_write_room(struct tty_struct *tty)
+static unsigned int gs_write_room(struct tty_struct *tty)
 {
 	struct gs_port	*port = tty->driver_data;
 	unsigned long	flags;
-	int		room = 0;
+	unsigned int room = 0;
 
 	spin_lock_irqsave(&port->port_lock, flags);
 	if (port->port_usb)
 		room = kfifo_avail(&port->port_write_buf);
 	spin_unlock_irqrestore(&port->port_lock, flags);
 
-	pr_vdebug("gs_write_room: (%d,%p) room=%d\n",
+	pr_vdebug("gs_write_room: (%d,%p) room=%u\n",
 		port->port_num, tty, room);
 
 	return room;
 }
 
-static int gs_chars_in_buffer(struct tty_struct *tty)
+static unsigned int gs_chars_in_buffer(struct tty_struct *tty)
 {
 	struct gs_port	*port = tty->driver_data;
 	unsigned long	flags;
-	int		chars = 0;
+	unsigned int	chars;
 
 	spin_lock_irqsave(&port->port_lock, flags);
 	chars = kfifo_len(&port->port_write_buf);
 	spin_unlock_irqrestore(&port->port_lock, flags);
 
-	pr_vdebug("gs_chars_in_buffer: (%d,%p) chars=%d\n",
+	pr_vdebug("gs_chars_in_buffer: (%d,%p) chars=%u\n",
 		port->port_num, tty, chars);
 
 	return chars;
@@ -1198,7 +1198,7 @@ void gserial_free_line(unsigned char port_num)
 	struct gs_port	*port;
 
 	mutex_lock(&ports[port_num].lock);
-	if (WARN_ON(!ports[port_num].port)) {
+	if (!ports[port_num].port) {
 		mutex_unlock(&ports[port_num].lock);
 		return;
 	}
diff --git a/drivers/usb/gadget/function/u_uac2.h b/drivers/usb/gadget/function/u_uac2.h
index b5035711172d..179d3ef6a195 100644
--- a/drivers/usb/gadget/function/u_uac2.h
+++ b/drivers/usb/gadget/function/u_uac2.h
@@ -21,7 +21,9 @@
 #define UAC2_DEF_CCHMASK 0x3
 #define UAC2_DEF_CSRATE 64000
 #define UAC2_DEF_CSSIZE 2
+#define UAC2_DEF_CSYNC		USB_ENDPOINT_SYNC_ASYNC
 #define UAC2_DEF_REQ_NUM 2
+#define UAC2_DEF_FB_MAX 5
 
 struct f_uac2_opts {
 	struct usb_function_instance	func_inst;
@@ -31,7 +33,9 @@ struct f_uac2_opts {
 	int				c_chmask;
 	int				c_srate;
 	int				c_ssize;
+	int				c_sync;
 	int				req_number;
+	int				fb_max;
 	bool				bound;
 
 	struct mutex			lock;
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index cd28dec837dd..77d64031aa9c 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -914,8 +914,6 @@ static int uvcg_streaming_header_allow_link(struct config_item *src,
 
 	target_fmt = container_of(to_config_group(target), struct uvcg_format,
 				  group);
-	if (!target_fmt)
-		goto out;
 
 	uvcg_format_set_indices(to_config_group(target));
 
@@ -955,8 +953,6 @@ static void uvcg_streaming_header_drop_link(struct config_item *src,
 	mutex_lock(&opts->lock);
 	target_fmt = container_of(to_config_group(target), struct uvcg_format,
 				  group);
-	if (!target_fmt)
-		goto out;
 
 	list_for_each_entry_safe(format_ptr, tmp, &src_hdr->formats, entry)
 		if (format_ptr->fmt == target_fmt) {
@@ -968,7 +964,6 @@ static void uvcg_streaming_header_drop_link(struct config_item *src,
 
 	--target_fmt->linked;
 
-out:
 	mutex_unlock(&opts->lock);
 	mutex_unlock(su_mutex);
 }