diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
new file mode 100644
index 0000000..b368b29
--- /dev/null
+++ b/include/linux/tty_driver.h
@@ -0,0 +1,279 @@
+#ifndef _LINUX_TTY_DRIVER_H
+#define _LINUX_TTY_DRIVER_H
+
+/*
+ * This structure defines the interface between the low-level tty
+ * driver and the tty routines.  The following routines can be
+ * defined; unless noted otherwise, they are optional, and can be
+ * filled in with a null pointer.
+ *
+ * int  (*open)(struct tty_struct * tty, struct file * filp);
+ *
+ * 	This routine is called when a particular tty device is opened.
+ * 	This routine is mandatory; if this routine is not filled in,
+ * 	the attempted open will fail with ENODEV.
+ *     
+ * void (*close)(struct tty_struct * tty, struct file * filp);
+ *
+ * 	This routine is called when a particular tty device is closed.
+ *
+ * int (*write)(struct tty_struct * tty,
+ * 		 const unsigned char *buf, int count);
+ *
+ * 	This routine is called by the kernel to write a series of
+ * 	characters to the tty device.  The characters may come from
+ * 	user space or kernel space.  This routine will return the
+ *	number of characters actually accepted for writing.  This
+ *	routine is mandatory.
+ *
+ * void (*put_char)(struct tty_struct *tty, unsigned char ch);
+ *
+ * 	This routine is called by the kernel to write a single
+ * 	character to the tty device.  If the kernel uses this routine,
+ * 	it must call the flush_chars() routine (if defined) when it is
+ * 	done stuffing characters into the driver.  If there is no room
+ * 	in the queue, the character is ignored.
+ *
+ * void (*flush_chars)(struct tty_struct *tty);
+ *
+ * 	This routine is called by the kernel after it has written a
+ * 	series of characters to the tty device using put_char().  
+ * 
+ * int  (*write_room)(struct tty_struct *tty);
+ *
+ * 	This routine returns the numbers of characters the tty driver
+ * 	will accept for queuing to be written.  This number is subject
+ * 	to change as output buffers get emptied, or if the output flow
+ *	control is acted.
+ * 
+ * int  (*ioctl)(struct tty_struct *tty, struct file * file,
+ * 	    unsigned int cmd, unsigned long arg);
+ *
+ * 	This routine allows the tty driver to implement
+ *	device-specific ioctl's.  If the ioctl number passed in cmd
+ * 	is not recognized by the driver, it should return ENOIOCTLCMD.
+ * 
+ * void (*set_termios)(struct tty_struct *tty, struct termios * old);
+ *
+ * 	This routine allows the tty driver to be notified when
+ * 	device's termios settings have changed.  Note that a
+ * 	well-designed tty driver should be prepared to accept the case
+ * 	where old == NULL, and try to do something rational.
+ *
+ * void (*set_ldisc)(struct tty_struct *tty);
+ *
+ * 	This routine allows the tty driver to be notified when the
+ * 	device's termios settings have changed.
+ * 
+ * void (*throttle)(struct tty_struct * tty);
+ *
+ * 	This routine notifies the tty driver that input buffers for
+ * 	the line discipline are close to full, and it should somehow
+ * 	signal that no more characters should be sent to the tty.
+ * 
+ * void (*unthrottle)(struct tty_struct * tty);
+ *
+ * 	This routine notifies the tty drivers that it should signals
+ * 	that characters can now be sent to the tty without fear of
+ * 	overrunning the input buffers of the line disciplines.
+ * 
+ * void (*stop)(struct tty_struct *tty);
+ *
+ * 	This routine notifies the tty driver that it should stop
+ * 	outputting characters to the tty device.  
+ * 
+ * void (*start)(struct tty_struct *tty);
+ *
+ * 	This routine notifies the tty driver that it resume sending
+ *	characters to the tty device.
+ * 
+ * void (*hangup)(struct tty_struct *tty);
+ *
+ * 	This routine notifies the tty driver that it should hangup the
+ * 	tty device.
+ *
+ * void (*break_ctl)(struct tty_stuct *tty, int state);
+ *
+ * 	This optional routine requests the tty driver to turn on or
+ * 	off BREAK status on the RS-232 port.  If state is -1,
+ * 	then the BREAK status should be turned on; if state is 0, then
+ * 	BREAK should be turned off.
+ *
+ * 	If this routine is implemented, the high-level tty driver will
+ * 	handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
+ * 	TIOCCBRK.  Otherwise, these ioctls will be passed down to the
+ * 	driver to handle.
+ *
+ * void (*wait_until_sent)(struct tty_struct *tty, int timeout);
+ * 
+ * 	This routine waits until the device has written out all of the
+ * 	characters in its transmitter FIFO.
+ *
+ * void (*send_xchar)(struct tty_struct *tty, char ch);
+ *
+ * 	This routine is used to send a high-priority XON/XOFF
+ * 	character to the device.
+ */
+
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <linux/cdev.h>
+
+struct tty_struct;
+
+struct tty_operations {
+	int  (*open)(struct tty_struct * tty, struct file * filp);
+	void (*close)(struct tty_struct * tty, struct file * filp);
+	int  (*write)(struct tty_struct * tty,
+		      const unsigned char *buf, int count);
+	void (*put_char)(struct tty_struct *tty, unsigned char ch);
+	void (*flush_chars)(struct tty_struct *tty);
+	int  (*write_room)(struct tty_struct *tty);
+	int  (*chars_in_buffer)(struct tty_struct *tty);
+	int  (*ioctl)(struct tty_struct *tty, struct file * file,
+		    unsigned int cmd, unsigned long arg);
+	void (*set_termios)(struct tty_struct *tty, struct termios * old);
+	void (*throttle)(struct tty_struct * tty);
+	void (*unthrottle)(struct tty_struct * tty);
+	void (*stop)(struct tty_struct *tty);
+	void (*start)(struct tty_struct *tty);
+	void (*hangup)(struct tty_struct *tty);
+	void (*break_ctl)(struct tty_struct *tty, int state);
+	void (*flush_buffer)(struct tty_struct *tty);
+	void (*set_ldisc)(struct tty_struct *tty);
+	void (*wait_until_sent)(struct tty_struct *tty, int timeout);
+	void (*send_xchar)(struct tty_struct *tty, char ch);
+	int (*read_proc)(char *page, char **start, off_t off,
+			  int count, int *eof, void *data);
+	int (*write_proc)(struct file *file, const char __user *buffer,
+			  unsigned long count, void *data);
+	int (*tiocmget)(struct tty_struct *tty, struct file *file);
+	int (*tiocmset)(struct tty_struct *tty, struct file *file,
+			unsigned int set, unsigned int clear);
+};
+
+struct tty_driver {
+	int	magic;		/* magic number for this structure */
+	struct cdev cdev;
+	struct module	*owner;
+	const char	*driver_name;
+	const char	*devfs_name;
+	const char	*name;
+	int	name_base;	/* offset of printed name */
+	int	major;		/* major device number */
+	int	minor_start;	/* start of minor device number */
+	int	minor_num;	/* number of *possible* devices */
+	int	num;		/* number of devices allocated */
+	short	type;		/* type of tty driver */
+	short	subtype;	/* subtype of tty driver */
+	struct termios init_termios; /* Initial termios */
+	int	flags;		/* tty driver flags */
+	int	refcount;	/* for loadable tty drivers */
+	struct proc_dir_entry *proc_entry; /* /proc fs entry */
+	struct tty_driver *other; /* only used for the PTY driver */
+
+	/*
+	 * Pointer to the tty data structures
+	 */
+	struct tty_struct **ttys;
+	struct termios **termios;
+	struct termios **termios_locked;
+	void *driver_state;	/* only used for the PTY driver */
+	
+	/*
+	 * Interface routines from the upper tty layer to the tty
+	 * driver.	Will be replaced with struct tty_operations.
+	 */
+	int  (*open)(struct tty_struct * tty, struct file * filp);
+	void (*close)(struct tty_struct * tty, struct file * filp);
+	int  (*write)(struct tty_struct * tty,
+		      const unsigned char *buf, int count);
+	void (*put_char)(struct tty_struct *tty, unsigned char ch);
+	void (*flush_chars)(struct tty_struct *tty);
+	int  (*write_room)(struct tty_struct *tty);
+	int  (*chars_in_buffer)(struct tty_struct *tty);
+	int  (*ioctl)(struct tty_struct *tty, struct file * file,
+		    unsigned int cmd, unsigned long arg);
+	void (*set_termios)(struct tty_struct *tty, struct termios * old);
+	void (*throttle)(struct tty_struct * tty);
+	void (*unthrottle)(struct tty_struct * tty);
+	void (*stop)(struct tty_struct *tty);
+	void (*start)(struct tty_struct *tty);
+	void (*hangup)(struct tty_struct *tty);
+	void (*break_ctl)(struct tty_struct *tty, int state);
+	void (*flush_buffer)(struct tty_struct *tty);
+	void (*set_ldisc)(struct tty_struct *tty);
+	void (*wait_until_sent)(struct tty_struct *tty, int timeout);
+	void (*send_xchar)(struct tty_struct *tty, char ch);
+	int (*read_proc)(char *page, char **start, off_t off,
+			  int count, int *eof, void *data);
+	int (*write_proc)(struct file *file, const char __user *buffer,
+			  unsigned long count, void *data);
+	int (*tiocmget)(struct tty_struct *tty, struct file *file);
+	int (*tiocmset)(struct tty_struct *tty, struct file *file,
+			unsigned int set, unsigned int clear);
+
+	struct list_head tty_drivers;
+};
+
+extern struct list_head tty_drivers;
+
+struct tty_driver *alloc_tty_driver(int lines);
+void put_tty_driver(struct tty_driver *driver);
+void tty_set_operations(struct tty_driver *driver, struct tty_operations *op);
+
+/* tty driver magic number */
+#define TTY_DRIVER_MAGIC		0x5402
+
+/*
+ * tty driver flags
+ * 
+ * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the
+ * 	termios setting when the last process has closed the device.
+ * 	Used for PTY's, in particular.
+ * 
+ * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
+ * 	guarantee never not to set any special character handling
+ * 	flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
+ * 	!INPCK)).  That is, if there is no reason for the driver to
+ * 	send notifications of parity and break characters up to the
+ * 	line driver, it won't do so.  This allows the line driver to
+ *	optimize for this case if this flag is set.  (Note that there
+ * 	is also a promise, if the above case is true, not to signal
+ * 	overruns, either.)
+ *
+ * TTY_DRIVER_NO_DEVFS --- if set, do not create devfs entries. This
+ *	is only used by tty_register_driver().
+ *
+ * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
+ *	use dynamic memory keyed through the devpts filesystem.  This
+ *	is only applicable to the pty driver.
+ */
+#define TTY_DRIVER_INSTALLED		0x0001
+#define TTY_DRIVER_RESET_TERMIOS	0x0002
+#define TTY_DRIVER_REAL_RAW		0x0004
+#define TTY_DRIVER_NO_DEVFS		0x0008
+#define TTY_DRIVER_DEVPTS_MEM		0x0010
+
+/* tty driver types */
+#define TTY_DRIVER_TYPE_SYSTEM		0x0001
+#define TTY_DRIVER_TYPE_CONSOLE		0x0002
+#define TTY_DRIVER_TYPE_SERIAL		0x0003
+#define TTY_DRIVER_TYPE_PTY		0x0004
+#define TTY_DRIVER_TYPE_SCC		0x0005	/* scc driver */
+#define TTY_DRIVER_TYPE_SYSCONS		0x0006
+
+/* system subtypes (magic, used by tty_io.c) */
+#define SYSTEM_TYPE_TTY			0x0001
+#define SYSTEM_TYPE_CONSOLE		0x0002
+#define SYSTEM_TYPE_SYSCONS		0x0003
+#define SYSTEM_TYPE_SYSPTMX		0x0004
+
+/* pty subtypes (magic, used by tty_io.c) */
+#define PTY_TYPE_MASTER			0x0001
+#define PTY_TYPE_SLAVE			0x0002
+
+/* serial subtype definitions */
+#define SERIAL_TYPE_NORMAL	1
+
+#endif /* #ifdef _LINUX_TTY_DRIVER_H */