diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c
index 9f7fc71474b4..d01fffeac951 100644
--- a/drivers/char/synclink_gt.c
+++ b/drivers/char/synclink_gt.c
@@ -301,6 +301,8 @@ struct slgt_info {
 	unsigned int rx_pio;
 	unsigned int if_mode;
 	unsigned int base_clock;
+	unsigned int xsync;
+	unsigned int xctrl;
 
 	/* device status */
 
@@ -405,6 +407,8 @@ static MGSL_PARAMS default_params = {
 #define TDCSR 0x94 /* tx DMA control/status */
 #define RDDAR 0x98 /* rx DMA descriptor address */
 #define TDDAR 0x9c /* tx DMA descriptor address */
+#define XSR   0x40 /* extended sync pattern */
+#define XCR   0x44 /* extended control */
 
 #define RXIDLE      BIT14
 #define RXBREAK     BIT14
@@ -517,6 +521,10 @@ static int  set_interface(struct slgt_info *info, int if_mode);
 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
+static int  get_xsync(struct slgt_info *info, int __user *if_mode);
+static int  set_xsync(struct slgt_info *info, int if_mode);
+static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
+static int  set_xctrl(struct slgt_info *info, int if_mode);
 
 /*
  * driver functions
@@ -1056,6 +1064,14 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		return get_gpio(info, argp);
 	case MGSL_IOCWAITGPIO:
 		return wait_gpio(info, argp);
+	case MGSL_IOCGXSYNC:
+		return get_xsync(info, argp);
+	case MGSL_IOCSXSYNC:
+		return set_xsync(info, (int)arg);
+	case MGSL_IOCGXCTRL:
+		return get_xctrl(info, argp);
+	case MGSL_IOCSXCTRL:
+		return set_xctrl(info, (int)arg);
 	}
 	mutex_lock(&info->port.mutex);
 	switch (cmd) {
@@ -1213,12 +1229,16 @@ static long slgt_compat_ioctl(struct tty_struct *tty, struct file *file,
 	case MGSL_IOCSGPIO:
 	case MGSL_IOCGGPIO:
 	case MGSL_IOCWAITGPIO:
+	case MGSL_IOCGXSYNC:
+	case MGSL_IOCGXCTRL:
 	case MGSL_IOCSTXIDLE:
 	case MGSL_IOCTXENABLE:
 	case MGSL_IOCRXENABLE:
 	case MGSL_IOCTXABORT:
 	case TIOCMIWAIT:
 	case MGSL_IOCSIF:
+	case MGSL_IOCSXSYNC:
+	case MGSL_IOCSXCTRL:
 		rc = ioctl(tty, file, cmd, arg);
 		break;
 	}
@@ -1961,6 +1981,7 @@ static void bh_handler(struct work_struct *work)
 			case MGSL_MODE_RAW:
 			case MGSL_MODE_MONOSYNC:
 			case MGSL_MODE_BISYNC:
+			case MGSL_MODE_XSYNC:
 				while(rx_get_buf(info));
 				break;
 			}
@@ -2889,6 +2910,69 @@ static int set_interface(struct slgt_info *info, int if_mode)
 	return 0;
 }
 
+static int get_xsync(struct slgt_info *info, int __user *xsync)
+{
+	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
+	if (put_user(info->xsync, xsync))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ * set extended sync pattern (1 to 4 bytes) for extended sync mode
+ *
+ * sync pattern is contained in least significant bytes of value
+ * most significant byte of sync pattern is oldest (1st sent/detected)
+ */
+static int set_xsync(struct slgt_info *info, int xsync)
+{
+	unsigned long flags;
+
+	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
+	spin_lock_irqsave(&info->lock, flags);
+	info->xsync = xsync;
+	wr_reg32(info, XSR, xsync);
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int get_xctrl(struct slgt_info *info, int __user *xctrl)
+{
+	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
+	if (put_user(info->xctrl, xctrl))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ * set extended control options
+ *
+ * xctrl[31:19] reserved, must be zero
+ * xctrl[18:17] extended sync pattern length in bytes
+ *              00 = 1 byte  in xsr[7:0]
+ *              01 = 2 bytes in xsr[15:0]
+ *              10 = 3 bytes in xsr[23:0]
+ *              11 = 4 bytes in xsr[31:0]
+ * xctrl[16]    1 = enable terminal count, 0=disabled
+ * xctrl[15:0]  receive terminal count for fixed length packets
+ *              value is count minus one (0 = 1 byte packet)
+ *              when terminal count is reached, receiver
+ *              automatically returns to hunt mode and receive
+ *              FIFO contents are flushed to DMA buffers with
+ *              end of frame (EOF) status
+ */
+static int set_xctrl(struct slgt_info *info, int xctrl)
+{
+	unsigned long flags;
+
+	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
+	spin_lock_irqsave(&info->lock, flags);
+	info->xctrl = xctrl;
+	wr_reg32(info, XCR, xctrl);
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
 /*
  * set general purpose IO pin state and direction
  *
@@ -3768,7 +3852,9 @@ module_exit(slgt_exit);
 #define CALC_REGADDR() \
 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
 	if (addr >= 0x80) \
-		reg_addr += (info->port_num) * 32;
+		reg_addr += (info->port_num) * 32; \
+	else if (addr >= 0x40)	\
+		reg_addr += (info->port_num) * 16;
 
 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
 {
@@ -4187,7 +4273,13 @@ static void sync_mode(struct slgt_info *info)
 
 	/* TCR (tx control)
 	 *
-	 * 15..13  mode, 000=HDLC 001=raw 010=async 011=monosync 100=bisync
+	 * 15..13  mode
+	 *         000=HDLC/SDLC
+	 *         001=raw bit synchronous
+	 *         010=asynchronous/isochronous
+	 *         011=monosync byte synchronous
+	 *         100=bisync byte synchronous
+	 *         101=xsync byte synchronous
 	 * 12..10  encoding
 	 * 09      CRC enable
 	 * 08      CRC32
@@ -4202,6 +4294,9 @@ static void sync_mode(struct slgt_info *info)
 	val = BIT2;
 
 	switch(info->params.mode) {
+	case MGSL_MODE_XSYNC:
+		val |= BIT15 + BIT13;
+		break;
 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
 	case MGSL_MODE_RAW:      val |= BIT13; break;
@@ -4256,7 +4351,13 @@ static void sync_mode(struct slgt_info *info)
 
 	/* RCR (rx control)
 	 *
-	 * 15..13  mode, 000=HDLC 001=raw 010=async 011=monosync 100=bisync
+	 * 15..13  mode
+	 *         000=HDLC/SDLC
+	 *         001=raw bit synchronous
+	 *         010=asynchronous/isochronous
+	 *         011=monosync byte synchronous
+	 *         100=bisync byte synchronous
+	 *         101=xsync byte synchronous
 	 * 12..10  encoding
 	 * 09      CRC enable
 	 * 08      CRC32
@@ -4268,6 +4369,9 @@ static void sync_mode(struct slgt_info *info)
 	val = 0;
 
 	switch(info->params.mode) {
+	case MGSL_MODE_XSYNC:
+		val |= BIT15 + BIT13;
+		break;
 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
 	case MGSL_MODE_RAW:      val |= BIT13; break;
@@ -4684,6 +4788,7 @@ static bool rx_get_buf(struct slgt_info *info)
 	switch(info->params.mode) {
 	case MGSL_MODE_MONOSYNC:
 	case MGSL_MODE_BISYNC:
+	case MGSL_MODE_XSYNC:
 		/* ignore residue in byte synchronous modes */
 		if (desc_residue(info->rbufs[i]))
 			count--;
diff --git a/include/linux/synclink.h b/include/linux/synclink.h
index 0ff2779c44d0..2e7d81c4e5ad 100644
--- a/include/linux/synclink.h
+++ b/include/linux/synclink.h
@@ -126,6 +126,7 @@
 #define MGSL_MODE_BISYNC	4
 #define MGSL_MODE_RAW		6
 #define MGSL_MODE_BASE_CLOCK    7
+#define MGSL_MODE_XSYNC         8
 
 #define MGSL_BUS_TYPE_ISA	1
 #define MGSL_BUS_TYPE_EISA	2
@@ -290,6 +291,10 @@ struct gpio_desc {
 #define MGSL_IOCSGPIO		_IOW(MGSL_MAGIC_IOC,16,struct gpio_desc)
 #define MGSL_IOCGGPIO		_IOR(MGSL_MAGIC_IOC,17,struct gpio_desc)
 #define MGSL_IOCWAITGPIO	_IOWR(MGSL_MAGIC_IOC,18,struct gpio_desc)
+#define MGSL_IOCSXSYNC		_IO(MGSL_MAGIC_IOC, 19)
+#define MGSL_IOCGXSYNC		_IO(MGSL_MAGIC_IOC, 20)
+#define MGSL_IOCSXCTRL		_IO(MGSL_MAGIC_IOC, 21)
+#define MGSL_IOCGXCTRL		_IO(MGSL_MAGIC_IOC, 22)
 
 #ifdef __KERNEL__
 /* provide 32 bit ioctl compatibility on 64 bit systems */