[Bluetooth]: Implement RFCOMM remote port negotiation

This patch implements the remote port negotiation (RPN) of the RFCOMM
protocol for Bluetooth.
Signed-off-by: J. Suter <jsuter@hardwave.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/bluetooth/rfcomm.h

@@ -80,9 +80,9 @@
 #define RFCOMM_RPN_STOP_15	1
 
 #define RFCOMM_RPN_PARITY_NONE	0x0
-#define RFCOMM_RPN_PARITY_ODD	0x4
-#define RFCOMM_RPN_PARITY_EVEN	0x5
-#define RFCOMM_RPN_PARITY_MARK	0x6
+#define RFCOMM_RPN_PARITY_ODD	0x1
+#define RFCOMM_RPN_PARITY_EVEN	0x3
+#define RFCOMM_RPN_PARITY_MARK	0x5
 #define RFCOMM_RPN_PARITY_SPACE	0x7
 
 #define RFCOMM_RPN_FLOW_NONE	0x00
@@ -223,6 +223,12 @@ struct rfcomm_dlc {
 #define RFCOMM_CFC_DISABLED 0
 #define RFCOMM_CFC_ENABLED  RFCOMM_MAX_CREDITS
 
+/* ---- RFCOMM SEND RPN ---- */
+int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
+			u8 bit_rate, u8 data_bits, u8 stop_bits,
+			u8 parity, u8 flow_ctrl_settings, 
+			u8 xon_char, u8 xoff_char, u16 param_mask);
+
 /* ---- RFCOMM DLCs (channels) ---- */
 struct rfcomm_dlc *rfcomm_dlc_alloc(int prio);
 void rfcomm_dlc_free(struct rfcomm_dlc *d);

net/bluetooth/rfcomm/core.c

@@ -21,10 +21,6 @@
    SOFTWARE IS DISCLAIMED.
 */
 
-/* 
-   RPN support    -    Dirk Husemann <hud@zurich.ibm.com>
-*/
-
 /*
  * Bluetooth RFCOMM core.
  *
@@ -115,10 +111,10 @@ static void rfcomm_session_del(struct rfcomm_session *s);
 #define __get_mcc_len(b)  ((b & 0xfe) >> 1)
 
 /* RPN macros */
-#define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x3) << 3))
+#define __rpn_line_settings(data, stop, parity)  ((data & 0x3) | ((stop & 0x1) << 2) | ((parity & 0x7) << 3))
 #define __get_rpn_data_bits(line) ((line) & 0x3)
 #define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
-#define __get_rpn_parity(line)    (((line) >> 3) & 0x3)
+#define __get_rpn_parity(line)    (((line) >> 3) & 0x7)
 
 static inline void rfcomm_schedule(uint event)
 {
@@ -780,7 +776,7 @@ static int rfcomm_send_pn(struct rfcomm_session *s, int cr, struct rfcomm_dlc *d
 	return rfcomm_send_frame(s, buf, ptr - buf);
 }
 
-static int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
+int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
 			u8 bit_rate, u8 data_bits, u8 stop_bits,
 			u8 parity, u8 flow_ctrl_settings, 
 			u8 xon_char, u8 xoff_char, u16 param_mask)
@@ -791,7 +787,7 @@ static int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
 	u8 buf[16], *ptr = buf;
 
 	BT_DBG("%p cr %d dlci %d bit_r 0x%x data_b 0x%x stop_b 0x%x parity 0x%x"
-	       "flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x", 
+			" flwc_s 0x%x xon_c 0x%x xoff_c 0x%x p_mask 0x%x", 
 		s, cr, dlci, bit_rate, data_bits, stop_bits, parity, 
 		flow_ctrl_settings, xon_char, xoff_char, param_mask);
 
@@ -1274,7 +1270,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 		return 0;
 
 	if (len == 1) {
-		/* request: return default setting */
+		/* This is a request, return default settings */
 		bit_rate  = RFCOMM_RPN_BR_115200;
 		data_bits = RFCOMM_RPN_DATA_8;
 		stop_bits = RFCOMM_RPN_STOP_1;
@@ -1282,11 +1278,12 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 		flow_ctrl = RFCOMM_RPN_FLOW_NONE;
 		xon_char  = RFCOMM_RPN_XON_CHAR;
 		xoff_char = RFCOMM_RPN_XOFF_CHAR;
-
 		goto rpn_out;
 	}
-	/* check for sane values: ignore/accept bit_rate, 8 bits, 1 stop bit, no parity,
-	                          no flow control lines, normal XON/XOFF chars */
+
+	/* Check for sane values, ignore/accept bit_rate, 8 bits, 1 stop bit,
+	 * no parity, no flow control lines, normal XON/XOFF chars */
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_BITRATE) {
 		bit_rate = rpn->bit_rate;
 		if (bit_rate != RFCOMM_RPN_BR_115200) {
@@ -1295,6 +1292,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_BITRATE;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_DATA) {
 		data_bits = __get_rpn_data_bits(rpn->line_settings);
 		if (data_bits != RFCOMM_RPN_DATA_8) {
@@ -1303,6 +1301,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_DATA;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_STOP) {
 		stop_bits = __get_rpn_stop_bits(rpn->line_settings);
 		if (stop_bits != RFCOMM_RPN_STOP_1) {
@@ -1311,6 +1310,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_STOP;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_PARITY) {
 		parity = __get_rpn_parity(rpn->line_settings);
 		if (parity != RFCOMM_RPN_PARITY_NONE) {
@@ -1319,6 +1319,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_PARITY;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_FLOW) {
 		flow_ctrl = rpn->flow_ctrl;
 		if (flow_ctrl != RFCOMM_RPN_FLOW_NONE) {
@@ -1327,6 +1328,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_FLOW;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_XON) {
 		xon_char = rpn->xon_char;
 		if (xon_char != RFCOMM_RPN_XON_CHAR) {
@@ -1335,6 +1337,7 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 			rpn_mask ^= RFCOMM_RPN_PM_XON;
 		}
 	}
+
 	if (rpn->param_mask & RFCOMM_RPN_PM_XOFF) {
 		xoff_char = rpn->xoff_char;
 		if (xoff_char != RFCOMM_RPN_XOFF_CHAR) {
@@ -1345,9 +1348,8 @@ static int rfcomm_recv_rpn(struct rfcomm_session *s, int cr, int len, struct sk_
 	}
 
 rpn_out:
-	rfcomm_send_rpn(s, 0, dlci, 
-			bit_rate, data_bits, stop_bits, parity, flow_ctrl,
-			xon_char, xoff_char, rpn_mask);
+	rfcomm_send_rpn(s, 0, dlci, bit_rate, data_bits, stop_bits,
+			parity, flow_ctrl, xon_char, xoff_char, rpn_mask);
 
 	return 0;
 }
@@ -1362,10 +1364,9 @@ static int rfcomm_recv_rls(struct rfcomm_session *s, int cr, struct sk_buff *skb
 	if (!cr)
 		return 0;
 
-	/* FIXME: We should probably do something with this
-	   information here. But for now it's sufficient just
-	   to reply -- Bluetooth 1.1 says it's mandatory to 
-	   recognise and respond to RLS */
+	/* We should probably do something with this information here. But
+	 * for now it's sufficient just to reply -- Bluetooth 1.1 says it's
+	 * mandatory to recognise and respond to RLS */
 
 	rfcomm_send_rls(s, 0, dlci, rls->status);
 

net/bluetooth/rfcomm/tty.c

@@ -745,20 +745,143 @@ static int rfcomm_tty_ioctl(struct tty_struct *tty, struct file *filp, unsigned
 	return -ENOIOCTLCMD;
 }
 
-#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
-
 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct termios *old)
 {
-	BT_DBG("tty %p", tty);
+	struct termios *new = (struct termios *) tty->termios;
+	int old_baud_rate = tty_termios_baud_rate(old);
+	int new_baud_rate = tty_termios_baud_rate(new);
 
-	if ((tty->termios->c_cflag == old->c_cflag) &&
-		(RELEVANT_IFLAG(tty->termios->c_iflag) == RELEVANT_IFLAG(old->c_iflag)))
-		return;
+	u8 baud, data_bits, stop_bits, parity, x_on, x_off;
+	u16 changes = 0;
+
+	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
+
+	BT_DBG("tty %p termios %p", tty, old);
+
+	/* Handle turning off CRTSCTS */
+	if ((old->c_cflag & CRTSCTS) && !(new->c_cflag & CRTSCTS)) 
+		BT_DBG("Turning off CRTSCTS unsupported");
 
-	/* handle turning off CRTSCTS */
-	if ((old->c_cflag & CRTSCTS) && !(tty->termios->c_cflag & CRTSCTS)) {
-		BT_DBG("turning off CRTSCTS");
+	/* Parity on/off and when on, odd/even */
+	if (((old->c_cflag & PARENB) != (new->c_cflag & PARENB)) ||
+			((old->c_cflag & PARODD) != (new->c_cflag & PARODD)) ) {
+		changes |= RFCOMM_RPN_PM_PARITY;
+		BT_DBG("Parity change detected.");
 	}
+
+	/* Mark and space parity are not supported! */
+	if (new->c_cflag & PARENB) {
+		if (new->c_cflag & PARODD) {
+			BT_DBG("Parity is ODD");
+			parity = RFCOMM_RPN_PARITY_ODD;
+		} else {
+			BT_DBG("Parity is EVEN");
+			parity = RFCOMM_RPN_PARITY_EVEN;
+		}
+	} else {
+		BT_DBG("Parity is OFF");
+		parity = RFCOMM_RPN_PARITY_NONE;
+	}
+
+	/* Setting the x_on / x_off characters */
+	if (old->c_cc[VSTOP] != new->c_cc[VSTOP]) {
+		BT_DBG("XOFF custom");
+		x_on = new->c_cc[VSTOP];
+		changes |= RFCOMM_RPN_PM_XON;
+	} else {
+		BT_DBG("XOFF default");
+		x_on = RFCOMM_RPN_XON_CHAR;
+	}
+
+	if (old->c_cc[VSTART] != new->c_cc[VSTART]) {
+		BT_DBG("XON custom");
+		x_off = new->c_cc[VSTART];
+		changes |= RFCOMM_RPN_PM_XOFF;
+	} else {
+		BT_DBG("XON default");
+		x_off = RFCOMM_RPN_XOFF_CHAR;
+	}
+
+	/* Handle setting of stop bits */
+	if ((old->c_cflag & CSTOPB) != (new->c_cflag & CSTOPB))
+		changes |= RFCOMM_RPN_PM_STOP;
+
+	/* POSIX does not support 1.5 stop bits and RFCOMM does not
+	 * support 2 stop bits. So a request for 2 stop bits gets
+	 * translated to 1.5 stop bits */
+	if (new->c_cflag & CSTOPB) {
+		stop_bits = RFCOMM_RPN_STOP_15;
+	} else {
+		stop_bits = RFCOMM_RPN_STOP_1;
+	}
+
+	/* Handle number of data bits [5-8] */
+	if ((old->c_cflag & CSIZE) != (new->c_cflag & CSIZE)) 
+		changes |= RFCOMM_RPN_PM_DATA;
+
+	switch (new->c_cflag & CSIZE) {
+	case CS5:
+		data_bits = RFCOMM_RPN_DATA_5;
+		break;
+	case CS6:
+		data_bits = RFCOMM_RPN_DATA_6;
+		break;
+	case CS7:
+		data_bits = RFCOMM_RPN_DATA_7;
+		break;
+	case CS8:
+		data_bits = RFCOMM_RPN_DATA_8;
+		break;
+	default:
+		data_bits = RFCOMM_RPN_DATA_8;
+		break;
+	}
+
+	/* Handle baudrate settings */
+	if (old_baud_rate != new_baud_rate)
+		changes |= RFCOMM_RPN_PM_BITRATE;
+
+	switch (new_baud_rate) {
+	case 2400:
+		baud = RFCOMM_RPN_BR_2400;
+		break;
+	case 4800:
+		baud = RFCOMM_RPN_BR_4800;
+		break;
+	case 7200:
+		baud = RFCOMM_RPN_BR_7200;
+		break;
+	case 9600:
+		baud = RFCOMM_RPN_BR_9600;
+		break;
+	case 19200: 
+		baud = RFCOMM_RPN_BR_19200;
+		break;
+	case 38400:
+		baud = RFCOMM_RPN_BR_38400;
+		break;
+	case 57600:
+		baud = RFCOMM_RPN_BR_57600;
+		break;
+	case 115200:
+		baud = RFCOMM_RPN_BR_115200;
+		break;
+	case 230400:
+		baud = RFCOMM_RPN_BR_230400;
+		break;
+	default:
+		/* 9600 is standard accordinag to the RFCOMM specification */
+		baud = RFCOMM_RPN_BR_9600;
+		break;
+	
+	}
+
+	if (changes)
+		rfcomm_send_rpn(dev->dlc->session, 1, dev->dlc->dlci, baud,
+				data_bits, stop_bits, parity,
+				RFCOMM_RPN_FLOW_NONE, x_on, x_off, changes);
+
+	return;
 }
 
 static void rfcomm_tty_throttle(struct tty_struct *tty)