Bluetooth: Add configuration support for ERTM and Streaming mode

Add support to config_req and config_rsp to configure ERTM and Streaming
mode. If the remote device specifies ERTM or Streaming mode, then the
same mode is proposed. Otherwise ERTM or Basic mode is used. And in case
of a state 2 device, the remote device should propose the same mode. If
not, then the channel gets disconnected.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/l2cap.h

@@ -27,8 +27,9 @@
 
 /* L2CAP defaults */
 #define L2CAP_DEFAULT_MTU		672
+#define L2CAP_DEFAULT_MIN_MTU		48
 #define L2CAP_DEFAULT_FLUSH_TO		0xffff
-#define L2CAP_DEFAULT_RX_WINDOW		1
+#define L2CAP_DEFAULT_TX_WINDOW		1
 #define L2CAP_DEFAULT_MAX_RECEIVE	1
 #define L2CAP_DEFAULT_RETRANS_TO	300    /* 300 milliseconds */
 #define L2CAP_DEFAULT_MONITOR_TO	1000   /* 1 second */
@@ -272,6 +273,9 @@ struct l2cap_pinfo {
 	__u16		omtu;
 	__u16		flush_to;
 	__u8		mode;
+	__u8		num_conf_req;
+	__u8		num_conf_rsp;
+
 	__u8		fcs;
 	__u8		sec_level;
 	__u8		role_switch;
@@ -280,23 +284,33 @@ struct l2cap_pinfo {
 	__u8		conf_req[64];
 	__u8		conf_len;
 	__u8		conf_state;
-	__u8		conf_retry;
 
 	__u8		ident;
 
+	__u8		remote_tx_win;
+	__u8		remote_max_tx;
+	__u16		retrans_timeout;
+	__u16		monitor_timeout;
+	__u16		max_pdu_size;
+
 	__le16		sport;
 
 	struct l2cap_conn	*conn;
 	struct sock		*next_c;
 	struct sock		*prev_c;
 };
 
-#define L2CAP_CONF_REQ_SENT	0x01
-#define L2CAP_CONF_INPUT_DONE	0x02
-#define L2CAP_CONF_OUTPUT_DONE	0x04
-#define L2CAP_CONF_CONNECT_PEND	0x80
+#define L2CAP_CONF_REQ_SENT       0x01
+#define L2CAP_CONF_INPUT_DONE     0x02
+#define L2CAP_CONF_OUTPUT_DONE    0x04
+#define L2CAP_CONF_MTU_DONE       0x08
+#define L2CAP_CONF_MODE_DONE      0x10
+#define L2CAP_CONF_CONNECT_PEND   0x20
+#define L2CAP_CONF_STATE2_DEVICE  0x80
+
+#define L2CAP_CONF_MAX_CONF_REQ 2
+#define L2CAP_CONF_MAX_CONF_RSP 2
 
-#define L2CAP_CONF_MAX_RETRIES	2
 
 void l2cap_load(void);