Bluetooth: Add connection parameter update response

Implements L2CAP Connection Parameter Update Response defined in
the Bluetooth Core Specification, Volume 3, Part A, section 4.21.
Address the LE Connection Parameter Procedure initiated by the slave.

Connection Interval Minimum and Maximum have the same range: 6 to
3200. Time = N * 1.25ms. Minimum shall be less or equal to Maximum.
The Slave Latency field shall have a value in the range of 0 to
((connSupervisionTimeout / connIntervalMax) - 1). Latency field shall
be less than 500. connSupervisionTimeout = Timeout Multiplier * 10 ms.
Multiplier field shall have a value in the range of 10 to 3200.

Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 06f245d..4f4bff1 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -261,6 +261,21 @@
 #define L2CAP_IR_SUCCESS    0x0000
 #define L2CAP_IR_NOTSUPP    0x0001
 
+struct l2cap_conn_param_update_req {
+	__le16      min;
+	__le16      max;
+	__le16      latency;
+	__le16      to_multiplier;
+} __packed;
+
+struct l2cap_conn_param_update_rsp {
+	__le16      result;
+} __packed;
+
+/* Connection Parameters result */
+#define L2CAP_CONN_PARAM_ACCEPTED	0x0000
+#define L2CAP_CONN_PARAM_REJECTED	0x0001
+
 /* ----- L2CAP connections ----- */
 struct l2cap_chan_list {
 	struct sock	*head;