Bluetooth: Add workaround for wrong HCI event in eSCO setup

The Broadcom chips with 2.1 firmware handle the fallback case to a SCO
link wrongly when setting up eSCO connections.

  < HCI Command: Setup Synchronous Connection (0x01|0x0028) plen 17
      handle 11 voice setting 0x0060
  > HCI Event: Command Status (0x0f) plen 4
      Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
  > HCI Event: Connect Complete (0x03) plen 11
      status 0x00 handle 1 bdaddr 00:1E:3A:xx:xx:xx type SCO encrypt 0x01

The Link Manager negotiates the fallback to SCO, but then sends out
a Connect Complete event. This is wrong and the Link Manager should
actually send a Synchronous Connection Complete event if the Setup
Synchronous Connection has been used. Only the remote side is allowed
to use Connect Complete to indicate the missing support for eSCO in
the host stack.

This patch adds a workaround for this which clearly should not be
needed, but reality is that broken Broadcom devices are deployed.

Based on a report by Ville Tervo <ville.tervo@nokia.com>

Signed-off-by: Marcel Holtman <marcel@holtmann.org>

1 files changed, 10 insertions, 2 deletions

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 963f9662eaa8..15f40ea8d544 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -866,8 +866,16 @@ static inline void hci_conn_complete_evt(struct hci_dev *hdev, struct sk_buff *s
 	hci_dev_lock(hdev);
 
 	conn = hci_conn_hash_lookup_ba(hdev, ev->link_type, &ev->bdaddr);
-	if (!conn)
-		goto unlock;
+	if (!conn) {
+		if (ev->link_type != SCO_LINK)
+			goto unlock;
+
+		conn = hci_conn_hash_lookup_ba(hdev, ESCO_LINK, &ev->bdaddr);
+		if (!conn)
+			goto unlock;
+
+		conn->type = SCO_LINK;
+	}
 
 	if (!ev->status) {
 		conn->handle = __le16_to_cpu(ev->handle);