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>

2 files changed, 28 insertions, 7 deletions

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index bfa9bcc0f5ef..48d730228c2f 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -29,6 +29,7 @@
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/mgmt.h>
 
 /* Handle HCI Event packets */
 
@@ -1875,6 +1876,22 @@ static void hci_conn_request_evt(struct hci_dev *hdev, struct sk_buff *skb)
         }
 }
 
+static u8 hci_to_mgmt_reason(u8 err)
+{
+        switch (err) {
+        case HCI_ERROR_CONNECTION_TIMEOUT:
+                return MGMT_DEV_DISCONN_TIMEOUT;
+        case HCI_ERROR_REMOTE_USER_TERM:
+        case HCI_ERROR_REMOTE_LOW_RESOURCES:
+        case HCI_ERROR_REMOTE_POWER_OFF:
+                return MGMT_DEV_DISCONN_REMOTE;
+        case HCI_ERROR_LOCAL_HOST_TERM:
+                return MGMT_DEV_DISCONN_LOCAL_HOST;
+        default:
+                return MGMT_DEV_DISCONN_UNKNOWN;
+        }
+}
+
 static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)
 {
         struct hci_ev_disconn_complete *ev = (void *) skb->data;
@@ -1893,12 +1910,15 @@ static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)
 
         if (test_and_clear_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags) &&
             (conn->type == ACL_LINK || conn->type == LE_LINK)) {
-                if (ev->status)
+                if (ev->status) {
                         mgmt_disconnect_failed(hdev, &conn->dst, conn->type,
                                                conn->dst_type, ev->status);
-                else
+                } else {
+                        u8 reason = hci_to_mgmt_reason(ev->reason);
+
                         mgmt_device_disconnected(hdev, &conn->dst, conn->type,
-                                                 conn->dst_type);
+                                                 conn->dst_type, reason);
+                }
         }
 
         if (ev->status == 0) {
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a3329cbd3e4d..05d4b83a0189 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3077,16 +3077,17 @@ static void unpair_device_rsp(struct pending_cmd *cmd, void *data)
 }
 
 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);