Bluetooth: Send HCI_Read_Clock_Offset before disconnecting

When the connection is in master role and it is going to be
disconnected based on the disconnection timeout, then send
the HCI_Read_Clock_Offset command in an attempt to update the
clock offset value in the inquiry cache.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

2 files changed, 24 insertions, 0 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index cc2e88dd20ea..6933766e7215 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -533,6 +533,11 @@ struct hci_cp_read_remote_version {
         __le16   handle;
 } __packed;
 
+#define HCI_OP_READ_CLOCK_OFFSET        0x041f
+struct hci_cp_read_clock_offset {
+        __le16   handle;
+} __packed;
+
 #define HCI_OP_SETUP_SYNC_CONN          0x0428
 struct hci_cp_setup_sync_conn {
         __le16   handle;
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 6d0fe3df2fa5..8a0c7a0ac1b6 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -309,6 +309,25 @@ static void hci_conn_timeout(struct work_struct *work)
                         hci_amp_disconn(conn);
                 } else {
                         __u8 reason = hci_proto_disconn_ind(conn);
+
+                        /* When we are master of an established connection
+                         * and it enters the disconnect timeout, then go
+                         * ahead and try to read the current clock offset.
+                         *
+                         * Processing of the result is done within the
+                         * event handling and hci_clock_offset_evt function.
+                         */
+                        if (conn->type == ACL_LINK &&
+                            test_bit(HCI_CONN_MASTER, &conn->flags)) {
+                                struct hci_dev *hdev = conn->hdev;
+                                struct hci_cp_read_clock_offset cp;
+
+                                cp.handle = cpu_to_le16(conn->handle);
+
+                                hci_send_cmd(hdev, HCI_OP_READ_CLOCK_OFFSET,
+                                             sizeof(cp), &cp);
+                        }
+
                         hci_disconnect(conn, reason);
                 }
                 break;