Patch to fix broken fake-CSR BT dongle

linux-fix-fake-bt-dongle.patch

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 80468745d..953eba56d 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -1768,6 +1768,7 @@ static int btusb_setup_csr(struct hci_dev *hdev)
 	struct hci_rp_read_local_version *rp;
 	struct sk_buff *skb;
 	bool is_fake = false;

 	BT_DBG("%s", hdev->name);

@@ -1856,6 +1857,52 @@ static int btusb_setup_csr(struct hci_dev *hdev)
 		 */
 		clear_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
 		clear_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
+
+		if (bcdDevice == 0x8891 &&
+                    le16_to_cpu(rp->lmp_subver) == 0x22bb &&
+                    le16_to_cpu(rp->hci_rev) == 0x3120 &&
+                    le16_to_cpu(rp->hci_ver) == BLUETOOTH_VER_4_0) {
+                        bt_dev_warn(hdev, "CSR: detected a fake CSR dongle with broken EDR filters\n");
+
+                        set_bit(HCI_QUIRK_BROKEN_EDR_FILTERS, &hdev->quirks);
+                }
 	}

 	kfree_skb(skb);
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index c8e67042a..af37b179d 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -238,6 +238,11 @@ enum {
 	 * during the hdev->setup vendor callback.
 	 */
 	HCI_QUIRK_BROKEN_ERR_DATA_REPORTING,
+
+	/* When this quirk is set, then EDR filters setting will be
+	 * excluded during initialization procedure.
+	 */
+	HCI_QUIRK_BROKEN_EDR_FILTERS
 };

 /* HCI device flags */
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index c4aa2cbb9..e19e48162 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -272,6 +272,7 @@ static void bredr_setup(struct hci_request *req)
 {
 	__le16 param;
 	__u8 flt_type;
+	struct hci_dev *hdev = req->hdev;

 	/* Read Buffer Size (ACL mtu, max pkt, etc.) */
 	hci_req_add(req, HCI_OP_READ_BUFFER_SIZE, 0, NULL);
@@ -291,9 +292,11 @@ static void bredr_setup(struct hci_request *req)
 	/* Read Current IAC LAP */
 	hci_req_add(req, HCI_OP_READ_CURRENT_IAC_LAP, 0, NULL);

-	/* Clear Event Filters */
-	flt_type = HCI_FLT_CLEAR_ALL;
-	hci_req_add(req, HCI_OP_SET_EVENT_FLT, 1, &flt_type);
+	if (!test_bit(HCI_QUIRK_BROKEN_EDR_FILTERS, &hdev->quirks)) {
+                /* Clear Event Filters */
+                flt_type = HCI_FLT_CLEAR_ALL;
+                hci_req_add(req, HCI_OP_SET_EVENT_FLT, 1, &flt_type);
+        }

 	/* Connection accept timeout ~20 secs */
 	param = cpu_to_le16(0x7d00);