File /code/usr/include/linux/tty_driver.h

#ifndef _LINUX_TTY_DRIVER_H
#define _LINUX_TTY_DRIVER_H



#include <linux/fs.h>

struct tty_driver {
	int	magic;		/* magic number for this structure */
	const char	*driver_name;
	const char	*name;
	int	name_base;	/* offset of printed name */
	short	major;		/* major device number */
	short	minor_start;	/* start of minor device number*/
	short	num;		/* number of devices */
	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 **table;
	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.
	 */
	int  (*open)(struct tty_struct * tty, struct file * filp);
	void (*close)(struct tty_struct * tty, struct file * filp);
	int  (*write)(struct tty_struct * tty, int from_user,
		      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 *buffer,
			  unsigned long count, void *data);

	/*
	 * linked list pointers
	 */
	struct tty_driver *next;
	struct tty_driver *prev;
};

/* 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().
 *
 */
#define TTY_DRIVER_INSTALLED		0x0001
#define TTY_DRIVER_RESET_TERMIOS	0x0002
#define TTY_DRIVER_REAL_RAW		0x0004
#define TTY_DRIVER_NO_DEVFS		0x0008

/* 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
#define SERIAL_TYPE_CALLOUT	2

#endif /* #ifdef _LINUX_TTY_DRIVER_H */