diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000000000..60d318f805ff1
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+permissions:
+  checks: write
+  pull-requests: write
+
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+    name: CI for Pull Request
+    steps:
+    - name: Checkout the source code
+      uses: actions/checkout@v3
+      with:
+        path: src/src
+
+    - name: CI
+      uses: bluez/action-ci@main
+      with:
+        task: ci
+        base_folder: src
+        space: kernel
+        github_token: ${{ secrets.GITHUB_TOKEN }}
+        email_token: ${{ secrets.EMAIL_TOKEN }}
+        patchwork_token: ${{ secrets.PATCHWORK_TOKEN }}
+        patchwork_user: ${{ secrets.PATCHWORK_USER }}
+
diff --git a/.github/workflows/sync.yml b/.github/workflows/sync.yml
new file mode 100644
index 0000000000000..5e95af92ab1ab
--- /dev/null
+++ b/.github/workflows/sync.yml
@@ -0,0 +1,44 @@
+name: Sync
+
+on:
+  schedule:
+  - cron: "*/5 * * * *"
+
+jobs:
+  sync_repo:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        ref: master
+
+    - name: Sync Repo
+      uses: bluez/action-ci@main
+      with:
+        task: sync
+        workflow: workflow
+        upstream_repo: 'https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git'
+        github_token: ${{ secrets.GITHUB_TOKEN }}
+
+    - name: Cleanup PR
+      uses: bluez/action-ci@main
+      with:
+        task: cleanup
+        github_token: ${{ secrets.ACTION_TOKEN }}
+
+  sync_patchwork:
+    needs: sync_repo
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Sync Patchwork
+      uses: bluez/action-ci@main
+      with:
+        task: patchwork
+        workflow: workflow
+        space: kernel
+        github_token: ${{ secrets.ACTION_TOKEN }}
+        email_token: ${{ secrets.EMAIL_TOKEN }}
+        patchwork_token: ${{ secrets.PATCHWORK_TOKEN }}
+        patchwork_user: ${{ secrets.PATCHWORK_USER }}
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 84614e60d142f..b9c62d6acab56 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -27,8 +27,9 @@
 #include "btbcm.h"
 #include "btrtl.h"
 #include "btmtk.h"
+#include "hci_uart.h"
 
-#define VERSION "0.8"
+#define VERSION "1.0"
 
 static bool disable_scofix;
 static bool force_scofix;
@@ -983,6 +984,9 @@ struct btqca_data {
 #define BTUSB_ALT6_CONTINUOUS_TX	16
 #define BTUSB_HW_SSR_ACTIVE	17
 
+#define BTUSB_PROTO_LEGACY	0x00
+#define BTUSB_PROTO_H4		0x01
+
 struct btusb_data {
 	struct hci_dev       *hdev;
 	struct usb_device    *udev;
@@ -1016,6 +1020,7 @@ struct btusb_data {
 	struct sk_buff *evt_skb;
 	struct sk_buff *acl_skb;
 	struct sk_buff *sco_skb;
+	struct sk_buff *rx_skb;
 
 	struct usb_endpoint_descriptor *intr_ep;
 	struct usb_endpoint_descriptor *bulk_tx_ep;
@@ -1029,6 +1034,7 @@ struct btusb_data {
 
 	__u8 cmdreq_type;
 	__u8 cmdreq;
+	__u8 proto;
 
 	unsigned int sco_num;
 	unsigned int air_mode;
@@ -1256,6 +1262,11 @@ static inline void btusb_free_frags(struct btusb_data *data)
 	dev_kfree_skb_irq(data->sco_skb);
 	data->sco_skb = NULL;
 
+	/* rx_skb may hold an ERR_PTR from a previous h4_recv_skb() call */
+	if (!IS_ERR(data->rx_skb))
+		dev_kfree_skb_irq(data->rx_skb);
+	data->rx_skb = NULL;
+
 	spin_unlock_irqrestore(&data->rxlock, flags);
 }
 
@@ -1355,12 +1366,41 @@ static int btusb_recv_acl(struct hci_dev *hdev, struct sk_buff *skb)
 	return 0;
 }
 
+/* Dispatch through the btusb_recv_* wrappers so that vendor specific
+ * handling (data->recv_event, data->recv_acl) is preserved in H:4 mode.
+ */
+static const struct h4_recv_pkt btusb_recv_pkts[] = {
+	{ H4_RECV_ACL,          .recv = btusb_recv_acl },
+	{ H4_RECV_SCO,          .recv = hci_recv_frame },
+	{ H4_RECV_EVENT,        .recv = btusb_recv_event },
+	{ H4_RECV_ISO,          .recv = hci_recv_frame },
+};
+
+static int btusb_recv_h4(struct btusb_data *data, void *buffer, int count)
+{
+	unsigned long flags;
+	int err = 0;
+
+	spin_lock_irqsave(&data->rxlock, flags);
+	data->rx_skb = h4_recv_skb(data->hdev, NULL, NULL, data->rx_skb, buffer,
+				   count, btusb_recv_pkts,
+				   ARRAY_SIZE(btusb_recv_pkts));
+	if (IS_ERR(data->rx_skb))
+		err = PTR_ERR(data->rx_skb);
+	spin_unlock_irqrestore(&data->rxlock, flags);
+
+	return err;
+}
+
 static int btusb_recv_bulk(struct btusb_data *data, void *buffer, int count)
 {
 	struct sk_buff *skb;
 	unsigned long flags;
 	int err = 0;
 
+	if (data->proto == BTUSB_PROTO_H4)
+		return btusb_recv_h4(data, buffer, count);
+
 	spin_lock_irqsave(&data->rxlock, flags);
 	skb = data->acl_skb;
 
@@ -2038,12 +2078,14 @@ static int btusb_open(struct hci_dev *hdev)
 
 	data->intf->needs_remote_wakeup = 1;
 
-	if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
-		goto done;
+	if (data->proto == BTUSB_PROTO_LEGACY) {
+		if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
+			goto done;
 
-	err = btusb_submit_intr_urb(hdev, GFP_KERNEL);
-	if (err < 0)
-		goto failed;
+		err = btusb_submit_intr_urb(hdev, GFP_KERNEL);
+		if (err < 0)
+			goto failed;
+	}
 
 	err = btusb_submit_bulk_urb(hdev, GFP_KERNEL);
 	if (err < 0) {
@@ -2141,56 +2183,64 @@ static int btusb_flush(struct hci_dev *hdev)
 	return 0;
 }
 
-static struct urb *alloc_ctrl_urb(struct hci_dev *hdev, struct sk_buff *skb)
+static struct urb *alloc_bulk_urb(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
-	struct usb_ctrlrequest *dr;
 	struct urb *urb;
 	unsigned int pipe;
 
+	if (!data->bulk_tx_ep)
+		return ERR_PTR(-ENODEV);
+
 	urb = usb_alloc_urb(0, GFP_KERNEL);
 	if (!urb)
 		return ERR_PTR(-ENOMEM);
 
-	dr = kmalloc_obj(*dr);
-	if (!dr) {
-		usb_free_urb(urb);
-		return ERR_PTR(-ENOMEM);
-	}
-
-	dr->bRequestType = data->cmdreq_type;
-	dr->bRequest     = data->cmdreq;
-	dr->wIndex       = 0;
-	dr->wValue       = 0;
-	dr->wLength      = __cpu_to_le16(skb->len);
+	pipe = usb_sndbulkpipe(data->udev, data->bulk_tx_ep->bEndpointAddress);
 
-	pipe = usb_sndctrlpipe(data->udev, 0x00);
+	if (data->proto == BTUSB_PROTO_H4) {
+		/* Prepend skb with frame type */
+		memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+	}
 
-	usb_fill_control_urb(urb, data->udev, pipe, (void *)dr,
-			     skb->data, skb->len, btusb_tx_complete, skb);
+	usb_fill_bulk_urb(urb, data->udev, pipe,
+			  skb->data, skb->len, btusb_tx_complete, skb);
 
 	skb->dev = (void *)hdev;
 
 	return urb;
 }
 
-static struct urb *alloc_bulk_urb(struct hci_dev *hdev, struct sk_buff *skb)
+static struct urb *alloc_ctrl_urb(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
+	struct usb_ctrlrequest *dr;
 	struct urb *urb;
 	unsigned int pipe;
 
-	if (!data->bulk_tx_ep)
-		return ERR_PTR(-ENODEV);
+	if (data->proto == BTUSB_PROTO_H4)
+		return alloc_bulk_urb(hdev, skb);
 
 	urb = usb_alloc_urb(0, GFP_KERNEL);
 	if (!urb)
 		return ERR_PTR(-ENOMEM);
 
-	pipe = usb_sndbulkpipe(data->udev, data->bulk_tx_ep->bEndpointAddress);
+	dr = kmalloc_obj(*dr);
+	if (!dr) {
+		usb_free_urb(urb);
+		return ERR_PTR(-ENOMEM);
+	}
 
-	usb_fill_bulk_urb(urb, data->udev, pipe,
-			  skb->data, skb->len, btusb_tx_complete, skb);
+	dr->bRequestType = data->cmdreq_type;
+	dr->bRequest     = data->cmdreq;
+	dr->wIndex       = 0;
+	dr->wValue       = 0;
+	dr->wLength      = __cpu_to_le16(skb->len);
+
+	pipe = usb_sndctrlpipe(data->udev, 0x00);
+
+	usb_fill_control_urb(urb, data->udev, pipe, (void *)dr,
+			     skb->data, skb->len, btusb_tx_complete, skb);
 
 	skb->dev = (void *)hdev;
 
@@ -2203,6 +2253,9 @@ static struct urb *alloc_isoc_urb(struct hci_dev *hdev, struct sk_buff *skb)
 	struct urb *urb;
 	unsigned int pipe;
 
+	if (data->proto == BTUSB_PROTO_H4)
+		return alloc_bulk_urb(hdev, skb);
+
 	if (!data->isoc_tx_ep)
 		return ERR_PTR(-ENODEV);
 
@@ -2416,10 +2469,9 @@ static int btusb_switch_alt_setting(struct hci_dev *hdev, int new_alts)
 	return 0;
 }
 
-static struct usb_host_interface *btusb_find_altsetting(struct btusb_data *data,
-							int alt)
+static struct usb_host_interface *
+btusb_find_altsetting(struct usb_interface *intf, int alt)
 {
-	struct usb_interface *intf = data->isoc;
 	int i;
 
 	BT_DBG("Looking for Alt no :%d", alt);
@@ -2475,9 +2527,9 @@ static void btusb_work(struct work_struct *work)
 			 * MTU >= 3 (packets) * 25 (size) - 3 (headers) = 72
 			 * see also Core spec 5, vol 4, B 2.1.1 & Table 2.1.
 			 */
-			if (btusb_find_altsetting(data, 6))
+			if (btusb_find_altsetting(data->isoc, 6))
 				new_alts = 6;
-			else if (btusb_find_altsetting(data, 3) &&
+			else if (btusb_find_altsetting(data->isoc, 3) &&
 				 hdev->sco_mtu >= 72 &&
 				 test_bit(BTUSB_USE_ALT3_FOR_WBS, &data->flags))
 				new_alts = 3;
@@ -3951,8 +4003,11 @@ static ssize_t force_poll_sync_write(struct file *file,
 	if (err)
 		return err;
 
-	/* Only allow changes while the adapter is down */
-	if (test_bit(HCI_UP, &data->hdev->flags))
+	/* Only allow changes while the adapter is down and it is using legacy
+	 * protocol.
+	 */
+	if (test_bit(HCI_UP, &data->hdev->flags) ||
+	    data->proto != BTUSB_PROTO_LEGACY)
 		return -EPERM;
 
 	if (data->poll_sync == enable)
@@ -4051,7 +4106,7 @@ static int btusb_hci_drv_supported_altsettings(struct hci_dev *hdev, void *data,
 		goto done;
 
 	for (i = 0; i <= 6; i++) {
-		if (btusb_find_altsetting(drvdata, i))
+		if (btusb_find_altsetting(drvdata->isoc, i))
 			rp->altsettings[rp->num++] = i;
 	}
 
@@ -4105,6 +4160,8 @@ static int btusb_probe(struct usb_interface *intf,
 		       const struct usb_device_id *id)
 {
 	struct gpio_desc *reset_gpio;
+	struct usb_host_interface *alt;
+	struct usb_endpoint_descriptor *ep;
 	struct btusb_data *data;
 	struct hci_dev *hdev;
 	unsigned ifnum_base;
@@ -4146,10 +4203,36 @@ static int btusb_probe(struct usb_interface *intf,
 		return -ENOMEM;
 
 	data->match_id = id;
+
+	/* Alternate setting 1 with a single pair of bulk endpoints means the
+	 * controller supports Bulk Serialization Mode, in which every packet
+	 * is prefixed with an H:4 header and carried over the bulk endpoints.
+	 */
+	alt = btusb_find_altsetting(intf, 1);
+	if (alt && usb_find_int_in_endpoint(alt, &ep) &&
+	    !usb_find_common_endpoints(alt, &ep, &ep, NULL, NULL)) {
+		err = usb_set_interface(interface_to_usbdev(intf), ifnum_base, 1);
+		if (!err)
+			data->proto = BTUSB_PROTO_H4;
+		else
+			dev_warn(&intf->dev,
+				 "failed to select alt setting 1 (%d), using legacy mode",
+				 err);
+	}
+
+	/* Check if all endpoints could be enumerated, legacy mode requires
+	 * interrupt and bulk endpoints while H4 mode only requires bulk
+	 * endpoints.
+	 */
 	err = usb_find_common_endpoints(intf->cur_altsetting, &data->bulk_rx_ep,
-					&data->bulk_tx_ep, &data->intr_ep, NULL);
-	if (err)
+					&data->bulk_tx_ep,
+					data->proto == BTUSB_PROTO_LEGACY ?
+						&data->intr_ep : NULL,
+					NULL);
+	if (err) {
+		dev_err(&intf->dev, "failed to enumerate endpoints\n");
 		goto err_free_data;
+	}
 
 	if (id->driver_info & BTUSB_AMP) {
 		data->cmdreq_type = USB_TYPE_CLASS | 0x01;
@@ -4361,6 +4444,12 @@ static int btusb_probe(struct usb_interface *intf,
 	if (id->driver_info & BTUSB_AMP) {
 		/* AMP controllers do not support SCO packets */
 		data->isoc = NULL;
+	} else if (data->proto == BTUSB_PROTO_H4) {
+		/* In H:4 mode every packet, including SCO/ISO, is carried over
+		 * the bulk endpoints, so the isochronous interface must not be
+		 * claimed nor have its alternate settings switched.
+		 */
+		data->isoc = NULL;
 	} else {
 		/* Interface orders are hardcoded in the specification */
 		data->isoc = usb_ifnum_to_if(data->udev, ifnum_base + 1);
@@ -4470,7 +4559,8 @@ static int btusb_probe(struct usb_interface *intf,
 	if (enable_autosuspend)
 		usb_enable_autosuspend(data->udev);
 
-	data->poll_sync = enable_poll_sync;
+	if (data->proto == BTUSB_PROTO_LEGACY)
+		data->poll_sync = enable_poll_sync;
 
 	err = hci_register_dev(hdev);
 	if (err < 0)
diff --git a/drivers/bluetooth/hci_h4.c b/drivers/bluetooth/hci_h4.c
index 7673727074985..cbdf51458ec3c 100644
--- a/drivers/bluetooth/hci_h4.c
+++ b/drivers/bluetooth/hci_h4.c
@@ -29,6 +29,7 @@
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/hci_h4.h>
 
 #include "hci_uart.h"
 
@@ -112,8 +113,9 @@ static int h4_recv(struct hci_uart *hu, const void *data, int count)
 	if (!h4)
 		return -ENODEV;
 
-	h4->rx_skb = h4_recv_buf(hu, h4->rx_skb, data, count,
-				 h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts));
+	h4->rx_skb = h4_recv_skb(hu->hdev, &hu->alignment, &hu->padding,
+				 h4->rx_skb, data, count, h4_recv_pkts,
+				 ARRAY_SIZE(h4_recv_pkts));
 	if (IS_ERR(h4->rx_skb)) {
 		int err = PTR_ERR(h4->rx_skb);
 		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
@@ -155,120 +157,7 @@ struct sk_buff *h4_recv_buf(struct hci_uart *hu, struct sk_buff *skb,
 			    const unsigned char *buffer, int count,
 			    const struct h4_recv_pkt *pkts, int pkts_count)
 {
-	u8 alignment = hu->alignment ? hu->alignment : 1;
-	struct hci_dev *hdev = hu->hdev;
-
-	/* Check for error from previous call */
-	if (IS_ERR(skb))
-		skb = NULL;
-
-	while (count) {
-		int i, len;
-
-		/* remove padding bytes from buffer */
-		for (; hu->padding && count > 0; hu->padding--) {
-			count--;
-			buffer++;
-		}
-		if (!count)
-			break;
-
-		if (!skb) {
-			for (i = 0; i < pkts_count; i++) {
-				if (buffer[0] != (&pkts[i])->type)
-					continue;
-
-				skb = bt_skb_alloc((&pkts[i])->maxlen,
-						   GFP_ATOMIC);
-				if (!skb)
-					return ERR_PTR(-ENOMEM);
-
-				hci_skb_pkt_type(skb) = (&pkts[i])->type;
-				hci_skb_expect(skb) = (&pkts[i])->hlen;
-				break;
-			}
-
-			/* Check for invalid packet type */
-			if (!skb)
-				return ERR_PTR(-EILSEQ);
-
-			count -= 1;
-			buffer += 1;
-		}
-
-		len = min_t(uint, hci_skb_expect(skb) - skb->len, count);
-		skb_put_data(skb, buffer, len);
-
-		count -= len;
-		buffer += len;
-
-		/* Check for partial packet */
-		if (skb->len < hci_skb_expect(skb))
-			continue;
-
-		for (i = 0; i < pkts_count; i++) {
-			if (hci_skb_pkt_type(skb) == (&pkts[i])->type)
-				break;
-		}
-
-		if (i >= pkts_count) {
-			kfree_skb(skb);
-			return ERR_PTR(-EILSEQ);
-		}
-
-		if (skb->len == (&pkts[i])->hlen) {
-			u16 dlen;
-
-			switch ((&pkts[i])->lsize) {
-			case 0:
-				/* No variable data length */
-				dlen = 0;
-				break;
-			case 1:
-				/* Single octet variable length */
-				dlen = skb->data[(&pkts[i])->loff];
-				hci_skb_expect(skb) += dlen;
-
-				if (skb_tailroom(skb) < dlen) {
-					kfree_skb(skb);
-					return ERR_PTR(-EMSGSIZE);
-				}
-				break;
-			case 2:
-				/* Double octet variable length */
-				dlen = get_unaligned_le16(skb->data +
-							  (&pkts[i])->loff);
-				hci_skb_expect(skb) += dlen;
-
-				if (skb_tailroom(skb) < dlen) {
-					kfree_skb(skb);
-					return ERR_PTR(-EMSGSIZE);
-				}
-				break;
-			default:
-				/* Unsupported variable length */
-				kfree_skb(skb);
-				return ERR_PTR(-EILSEQ);
-			}
-
-			if (!dlen) {
-				hu->padding = (skb->len + 1) % alignment;
-				hu->padding = (alignment - hu->padding) % alignment;
-
-				/* No more data, complete frame */
-				(&pkts[i])->recv(hdev, skb);
-				skb = NULL;
-			}
-		} else {
-			hu->padding = (skb->len + 1) % alignment;
-			hu->padding = (alignment - hu->padding) % alignment;
-
-			/* Complete frame */
-			(&pkts[i])->recv(hdev, skb);
-			skb = NULL;
-		}
-	}
-
-	return skb;
+	return h4_recv_skb(hu->hdev, &hu->alignment, &hu->padding, skb, buffer,
+			   count, pkts, pkts_count);
 }
 EXPORT_SYMBOL_GPL(h4_recv_buf);
diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
index 48ac7ca9334e5..7fbe8dffab988 100644
--- a/drivers/bluetooth/hci_uart.h
+++ b/drivers/bluetooth/hci_uart.h
@@ -8,6 +8,8 @@
  *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
  */
 
+#include <net/bluetooth/hci_h4.h>
+
 #ifndef N_HCI
 #define N_HCI	15
 #endif
@@ -121,43 +123,6 @@ void hci_uart_set_flow_control(struct hci_uart *hu, bool enable);
 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
 			 unsigned int oper_speed);
 
-struct h4_recv_pkt {
-	u8  type;	/* Packet type */
-	u8  hlen;	/* Header length */
-	u8  loff;	/* Data length offset in header */
-	u8  lsize;	/* Data length field size */
-	u16 maxlen;	/* Max overall packet length */
-	int (*recv)(struct hci_dev *hdev, struct sk_buff *skb);
-};
-
-#define H4_RECV_ACL \
-	.type = HCI_ACLDATA_PKT, \
-	.hlen = HCI_ACL_HDR_SIZE, \
-	.loff = 2, \
-	.lsize = 2, \
-	.maxlen = HCI_MAX_FRAME_SIZE \
-
-#define H4_RECV_SCO \
-	.type = HCI_SCODATA_PKT, \
-	.hlen = HCI_SCO_HDR_SIZE, \
-	.loff = 2, \
-	.lsize = 1, \
-	.maxlen = HCI_MAX_SCO_SIZE
-
-#define H4_RECV_EVENT \
-	.type = HCI_EVENT_PKT, \
-	.hlen = HCI_EVENT_HDR_SIZE, \
-	.loff = 1, \
-	.lsize = 1, \
-	.maxlen = HCI_MAX_EVENT_SIZE
-
-#define H4_RECV_ISO \
-	.type = HCI_ISODATA_PKT, \
-	.hlen = HCI_ISO_HDR_SIZE, \
-	.loff = 2, \
-	.lsize = 2, \
-	.maxlen = HCI_MAX_FRAME_SIZE \
-
 #ifdef CONFIG_BT_HCIUART_H4
 int h4_init(void);
 int h4_deinit(void);
diff --git a/include/net/bluetooth/hci_h4.h b/include/net/bluetooth/hci_h4.h
new file mode 100644
index 0000000000000..a37e7df8c9ce8
--- /dev/null
+++ b/include/net/bluetooth/hci_h4.h
@@ -0,0 +1,60 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  Bluetooth HCI H:4 packet reassembly
+ *
+ *  Copyright (C) 2000-2001  Qualcomm Incorporated
+ *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
+ *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
+ */
+
+#ifndef __HCI_H4_H
+#define __HCI_H4_H
+
+#include <linux/skbuff.h>
+#include <linux/types.h>
+
+struct hci_dev;
+
+struct h4_recv_pkt {
+	u8  type;	/* Packet type */
+	u8  hlen;	/* Header length */
+	u8  loff;	/* Data length offset in header */
+	u8  lsize;	/* Data length field size */
+	u16 maxlen;	/* Max overall packet length */
+	int (*recv)(struct hci_dev *hdev, struct sk_buff *skb);
+};
+
+#define H4_RECV_ACL \
+	.type = HCI_ACLDATA_PKT, \
+	.hlen = HCI_ACL_HDR_SIZE, \
+	.loff = 2, \
+	.lsize = 2, \
+	.maxlen = HCI_MAX_FRAME_SIZE \
+
+#define H4_RECV_SCO \
+	.type = HCI_SCODATA_PKT, \
+	.hlen = HCI_SCO_HDR_SIZE, \
+	.loff = 2, \
+	.lsize = 1, \
+	.maxlen = HCI_MAX_SCO_SIZE
+
+#define H4_RECV_EVENT \
+	.type = HCI_EVENT_PKT, \
+	.hlen = HCI_EVENT_HDR_SIZE, \
+	.loff = 1, \
+	.lsize = 1, \
+	.maxlen = HCI_MAX_EVENT_SIZE
+
+#define H4_RECV_ISO \
+	.type = HCI_ISODATA_PKT, \
+	.hlen = HCI_ISO_HDR_SIZE, \
+	.loff = 2, \
+	.lsize = 2, \
+	.maxlen = HCI_MAX_FRAME_SIZE \
+
+struct sk_buff *h4_recv_skb(struct hci_dev *hdev, u8 *alignment, u8 *padding,
+			    struct sk_buff *skb, const unsigned char *buffer,
+			    int count, const struct h4_recv_pkt *pkts,
+			    int pkts_count);
+
+#endif /* __HCI_H4_H */
diff --git a/net/bluetooth/Makefile b/net/bluetooth/Makefile
index ff466ea97436a..b78ad98864d4f 100644
--- a/net/bluetooth/Makefile
+++ b/net/bluetooth/Makefile
@@ -14,7 +14,7 @@ bluetooth_6lowpan-y := 6lowpan.o
 bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \
 	hci_sock.o hci_sysfs.o l2cap_core.o l2cap_sock.o smp.o lib.o \
 	ecdh_helper.o mgmt_util.o mgmt_config.o hci_codec.o eir.o hci_sync.o \
-	hci_drv.o
+	hci_drv.o hci_h4.o
 
 bluetooth-$(CONFIG_DEV_COREDUMP) += coredump.o
 
diff --git a/net/bluetooth/hci_h4.c b/net/bluetooth/hci_h4.c
new file mode 100644
index 0000000000000..86f809018062f
--- /dev/null
+++ b/net/bluetooth/hci_h4.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Bluetooth HCI H:4 packet reassembly
+ *
+ *  Copyright (C) 2000-2001  Qualcomm Incorporated
+ *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
+ *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
+ */
+
+#include <linux/export.h>
+#include <linux/skbuff.h>
+#include <linux/unaligned.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/hci_h4.h>
+
+/* h4_recv_skb - Reassemble H:4 framed packets
+ * @hdev: HCI device the packets are received on
+ * @alignment: optional packet alignment, NULL or 0 means no alignment
+ * @padding: optional padding state carried over between calls
+ * @skb: partially received packet from a previous call, may be NULL or an
+ *	 ERR_PTR returned by a previous call
+ * @buffer: buffer holding the received data
+ * @count: number of bytes in @buffer
+ * @pkts: table of supported packet types
+ * @pkts_count: number of entries in @pkts
+ *
+ * Returns the partially received packet to be passed to the next call, or an
+ * ERR_PTR on error. The returned value can be fed back into this function as
+ * is, but must be checked with IS_ERR() before being freed.
+ */
+struct sk_buff *h4_recv_skb(struct hci_dev *hdev, u8 *alignment, u8 *padding,
+			    struct sk_buff *skb, const unsigned char *buffer,
+			    int count, const struct h4_recv_pkt *pkts,
+			    int pkts_count)
+{
+	u8 align = alignment && *alignment ? *alignment : 1;
+
+	/* Check for error from previous call */
+	if (IS_ERR(skb))
+		skb = NULL;
+
+	while (count) {
+		int i, len;
+
+		/* remove padding bytes from buffer */
+		if (padding) {
+			for (; (*padding) && count > 0; (*padding)--) {
+				count--;
+				buffer++;
+			}
+		}
+
+		if (!count)
+			break;
+
+		if (!skb) {
+			for (i = 0; i < pkts_count; i++) {
+				if (buffer[0] != pkts[i].type)
+					continue;
+
+				skb = bt_skb_alloc(pkts[i].maxlen,
+						   GFP_ATOMIC);
+				if (!skb)
+					return ERR_PTR(-ENOMEM);
+
+				hci_skb_pkt_type(skb) = pkts[i].type;
+				hci_skb_expect(skb) = pkts[i].hlen;
+				break;
+			}
+
+			/* Check for invalid packet type */
+			if (!skb)
+				return ERR_PTR(-EILSEQ);
+
+			count -= 1;
+			buffer += 1;
+		}
+
+		len = min_t(uint, hci_skb_expect(skb) - skb->len, count);
+		skb_put_data(skb, buffer, len);
+
+		count -= len;
+		buffer += len;
+
+		/* Check for partial packet */
+		if (skb->len < hci_skb_expect(skb))
+			continue;
+
+		for (i = 0; i < pkts_count; i++) {
+			if (hci_skb_pkt_type(skb) == pkts[i].type)
+				break;
+		}
+
+		if (i >= pkts_count) {
+			kfree_skb(skb);
+			return ERR_PTR(-EILSEQ);
+		}
+
+		if (skb->len == pkts[i].hlen) {
+			u16 dlen;
+
+			switch (pkts[i].lsize) {
+			case 0:
+				/* No variable data length */
+				dlen = 0;
+				break;
+			case 1:
+				/* Single octet variable length */
+				dlen = skb->data[pkts[i].loff];
+				hci_skb_expect(skb) += dlen;
+
+				if (skb_tailroom(skb) < dlen) {
+					kfree_skb(skb);
+					return ERR_PTR(-EMSGSIZE);
+				}
+				break;
+			case 2:
+				/* Double octet variable length */
+				dlen = get_unaligned_le16(skb->data +
+							  pkts[i].loff);
+				hci_skb_expect(skb) += dlen;
+
+				if (skb_tailroom(skb) < dlen) {
+					kfree_skb(skb);
+					return ERR_PTR(-EMSGSIZE);
+				}
+				break;
+			default:
+				/* Unsupported variable length */
+				kfree_skb(skb);
+				return ERR_PTR(-EILSEQ);
+			}
+
+			if (!dlen) {
+				if (padding) {
+					*padding = (skb->len + 1) % align;
+					*padding = (align - *padding) % align;
+				}
+
+				/* No more data, complete frame */
+				pkts[i].recv(hdev, skb);
+				skb = NULL;
+			}
+		} else {
+			if (padding) {
+				*padding = (skb->len + 1) % align;
+				*padding = (align - *padding) % align;
+			}
+
+			/* Complete frame */
+			pkts[i].recv(hdev, skb);
+			skb = NULL;
+		}
+	}
+
+	return skb;
+}
+EXPORT_SYMBOL_GPL(h4_recv_skb);