Bluetooth: mgmt: Add device disconnect reason

MGMT_EV_DEVICE_DISCONNECTED will now expose the disconnection reason to
userland, distinguishing four possible values:

	0x00	Reason not known or unspecified
	0x01	Connection timeout
	0x02	Connection terminated by local host
	0x03	Connection terminated by remote host

Note that the local/remote distinction just determines which side
terminated the low-level connection, regardless of the disconnection of
the higher-level profiles.

This can sometimes be misleading and thus must be used with care. For
example, some hardware combinations would report a locally initiated
disconnection even if the user turned Bluetooth off in the remote side.

Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a3329cb..05d4b83 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3077,16 +3077,17 @@
 }
 
 int mgmt_device_disconnected(struct hci_dev *hdev, bdaddr_t *bdaddr,
-			     u8 link_type, u8 addr_type)
+			     u8 link_type, u8 addr_type, u8 reason)
 {
-	struct mgmt_addr_info ev;
+	struct mgmt_ev_device_disconnected ev;
 	struct sock *sk = NULL;
 	int err;
 
 	mgmt_pending_foreach(MGMT_OP_DISCONNECT, hdev, disconnect_rsp, &sk);
 
-	bacpy(&ev.bdaddr, bdaddr);
-	ev.type = link_to_bdaddr(link_type, addr_type);
+	bacpy(&ev.addr.bdaddr, bdaddr);
+	ev.addr.type = link_to_bdaddr(link_type, addr_type);
+	ev.reason = reason;
 
 	err = mgmt_event(MGMT_EV_DEVICE_DISCONNECTED, hdev, &ev, sizeof(ev),
 			 sk);