1 #ifndef _LINUX_TTY_DRIVER_H
2 #define _LINUX_TTY_DRIVER_H
5 * This structure defines the interface between the low-level tty
6 * driver and the tty routines. The following routines can be
7 * defined; unless noted otherwise, they are optional, and can be
8 * filled in with a null pointer.
10 * struct tty_struct * (*lookup)(struct tty_driver *self, int idx)
12 * Return the tty device corresponding to idx, NULL if there is not
13 * one currently in use and an ERR_PTR value on error. Called under
14 * tty_mutex (for now!)
16 * Optional method. Default behaviour is to use the ttys array
18 * int (*install)(struct tty_driver *self, struct tty_struct *tty)
20 * Install a new tty into the tty driver internal tables. Used in
21 * conjunction with lookup and remove methods.
23 * Optional method. Default behaviour is to use the ttys array
25 * void (*remove)(struct tty_driver *self, struct tty_struct *tty)
27 * Remove a closed tty from the tty driver internal tables. Used in
28 * conjunction with lookup and remove methods.
30 * Optional method. Default behaviour is to use the ttys array
32 * int (*open)(struct tty_struct * tty, struct file * filp);
34 * This routine is called when a particular tty device is opened.
35 * This routine is mandatory; if this routine is not filled in,
36 * the attempted open will fail with ENODEV.
40 * void (*close)(struct tty_struct * tty, struct file * filp);
42 * This routine is called when a particular tty device is closed.
46 * void (*shutdown)(struct tty_struct * tty);
48 * This routine is called synchronously when a particular tty device
49 * is closed for the last time freeing up the resources.
50 * Note that tty_shutdown() is not called if ops->shutdown is defined.
51 * This means one is responsible to take care of calling ops->remove (e.g.
52 * via tty_driver_remove_tty) and releasing tty->termios.
55 * void (*cleanup)(struct tty_struct * tty);
57 * This routine is called asynchronously when a particular tty device
58 * is closed for the last time freeing up the resources. This is
59 * actually the second part of shutdown for routines that might sleep.
62 * int (*write)(struct tty_struct * tty,
63 * const unsigned char *buf, int count);
65 * This routine is called by the kernel to write a series of
66 * characters to the tty device. The characters may come from
67 * user space or kernel space. This routine will return the
68 * number of characters actually accepted for writing.
70 * Optional: Required for writable devices.
72 * int (*put_char)(struct tty_struct *tty, unsigned char ch);
74 * This routine is called by the kernel to write a single
75 * character to the tty device. If the kernel uses this routine,
76 * it must call the flush_chars() routine (if defined) when it is
77 * done stuffing characters into the driver. If there is no room
78 * in the queue, the character is ignored.
80 * Optional: Kernel will use the write method if not provided.
82 * Note: Do not call this function directly, call tty_put_char
84 * void (*flush_chars)(struct tty_struct *tty);
86 * This routine is called by the kernel after it has written a
87 * series of characters to the tty device using put_char().
91 * Note: Do not call this function directly, call tty_driver_flush_chars
93 * int (*write_room)(struct tty_struct *tty);
95 * This routine returns the numbers of characters the tty driver
96 * will accept for queuing to be written. This number is subject
97 * to change as output buffers get emptied, or if the output flow
100 * Required if write method is provided else not needed.
102 * Note: Do not call this function directly, call tty_write_room
104 * int (*ioctl)(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
106 * This routine allows the tty driver to implement
107 * device-specific ioctls. If the ioctl number passed in cmd
108 * is not recognized by the driver, it should return ENOIOCTLCMD.
112 * long (*compat_ioctl)(struct tty_struct *tty,,
113 * unsigned int cmd, unsigned long arg);
115 * implement ioctl processing for 32 bit process on 64 bit system
119 * void (*set_termios)(struct tty_struct *tty, struct ktermios * old);
121 * This routine allows the tty driver to be notified when
122 * device's termios settings have changed.
124 * Optional: Called under the termios lock
127 * void (*set_ldisc)(struct tty_struct *tty);
129 * This routine allows the tty driver to be notified when the
130 * device's termios settings have changed.
132 * Optional: Called under BKL (currently)
134 * void (*throttle)(struct tty_struct * tty);
136 * This routine notifies the tty driver that input buffers for
137 * the line discipline are close to full, and it should somehow
138 * signal that no more characters should be sent to the tty.
140 * Optional: Always invoke via tty_throttle(), called under the
143 * void (*unthrottle)(struct tty_struct * tty);
145 * This routine notifies the tty drivers that it should signals
146 * that characters can now be sent to the tty without fear of
147 * overrunning the input buffers of the line disciplines.
149 * Optional: Always invoke via tty_unthrottle(), called under the
152 * void (*stop)(struct tty_struct *tty);
154 * This routine notifies the tty driver that it should stop
155 * outputting characters to the tty device.
159 * Note: Call stop_tty not this method.
161 * void (*start)(struct tty_struct *tty);
163 * This routine notifies the tty driver that it resume sending
164 * characters to the tty device.
168 * Note: Call start_tty not this method.
170 * void (*hangup)(struct tty_struct *tty);
172 * This routine notifies the tty driver that it should hang up the
177 * int (*break_ctl)(struct tty_struct *tty, int state);
179 * This optional routine requests the tty driver to turn on or
180 * off BREAK status on the RS-232 port. If state is -1,
181 * then the BREAK status should be turned on; if state is 0, then
182 * BREAK should be turned off.
184 * If this routine is implemented, the high-level tty driver will
185 * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
188 * If the driver sets TTY_DRIVER_HARDWARE_BREAK then the interface
189 * will also be called with actual times and the hardware is expected
190 * to do the delay work itself. 0 and -1 are still used for on/off.
192 * Optional: Required for TCSBRK/BRKP/etc handling.
194 * void (*wait_until_sent)(struct tty_struct *tty, int timeout);
196 * This routine waits until the device has written out all of the
197 * characters in its transmitter FIFO.
199 * Optional: If not provided the device is assumed to have no FIFO
201 * Note: Usually correct to call tty_wait_until_sent
203 * void (*send_xchar)(struct tty_struct *tty, char ch);
205 * This routine is used to send a high-priority XON/XOFF
206 * character to the device.
208 * Optional: If not provided then the write method is called under
209 * the atomic write lock to keep it serialized with the ldisc.
211 * int (*resize)(struct tty_struct *tty, struct winsize *ws)
213 * Called when a termios request is issued which changes the
214 * requested terminal geometry.
216 * Optional: the default action is to update the termios structure
217 * without error. This is usually the correct behaviour. Drivers should
218 * not force errors here if they are not resizable objects (eg a serial
219 * line). See tty_do_resize() if you need to wrap the standard method
220 * in your own logic - the usual case.
222 * void (*set_termiox)(struct tty_struct *tty, struct termiox *new);
224 * Called when the device receives a termiox based ioctl. Passes down
225 * the requested data from user space. This method will not be invoked
226 * unless the tty also has a valid tty->termiox pointer.
228 * Optional: Called under the termios lock
230 * int (*get_icount)(struct tty_struct *tty, struct serial_icounter *icount);
232 * Called when the device receives a TIOCGICOUNT ioctl. Passed a kernel
233 * structure to complete. This method is optional and will only be called
234 * if provided (otherwise EINVAL will be returned).
237 #include <linux/fs.h>
238 #include <linux/list.h>
239 #include <linux/cdev.h>
240 #include <linux/termios.h>
244 struct serial_icounter_struct
;
246 struct tty_operations
{
247 struct tty_struct
* (*lookup
)(struct tty_driver
*driver
,
248 struct inode
*inode
, int idx
);
249 int (*install
)(struct tty_driver
*driver
, struct tty_struct
*tty
);
250 void (*remove
)(struct tty_driver
*driver
, struct tty_struct
*tty
);
251 int (*open
)(struct tty_struct
* tty
, struct file
* filp
);
252 void (*close
)(struct tty_struct
* tty
, struct file
* filp
);
253 void (*shutdown
)(struct tty_struct
*tty
);
254 void (*cleanup
)(struct tty_struct
*tty
);
255 int (*write
)(struct tty_struct
* tty
,
256 const unsigned char *buf
, int count
);
257 int (*put_char
)(struct tty_struct
*tty
, unsigned char ch
);
258 void (*flush_chars
)(struct tty_struct
*tty
);
259 int (*write_room
)(struct tty_struct
*tty
);
260 int (*chars_in_buffer
)(struct tty_struct
*tty
);
261 int (*ioctl
)(struct tty_struct
*tty
,
262 unsigned int cmd
, unsigned long arg
);
263 long (*compat_ioctl
)(struct tty_struct
*tty
,
264 unsigned int cmd
, unsigned long arg
);
265 void (*set_termios
)(struct tty_struct
*tty
, struct ktermios
* old
);
266 void (*throttle
)(struct tty_struct
* tty
);
267 void (*unthrottle
)(struct tty_struct
* tty
);
268 void (*stop
)(struct tty_struct
*tty
);
269 void (*start
)(struct tty_struct
*tty
);
270 void (*hangup
)(struct tty_struct
*tty
);
271 int (*break_ctl
)(struct tty_struct
*tty
, int state
);
272 void (*flush_buffer
)(struct tty_struct
*tty
);
273 void (*set_ldisc
)(struct tty_struct
*tty
);
274 void (*wait_until_sent
)(struct tty_struct
*tty
, int timeout
);
275 void (*send_xchar
)(struct tty_struct
*tty
, char ch
);
276 int (*tiocmget
)(struct tty_struct
*tty
);
277 int (*tiocmset
)(struct tty_struct
*tty
,
278 unsigned int set
, unsigned int clear
);
279 int (*resize
)(struct tty_struct
*tty
, struct winsize
*ws
);
280 int (*set_termiox
)(struct tty_struct
*tty
, struct termiox
*tnew
);
281 int (*get_icount
)(struct tty_struct
*tty
,
282 struct serial_icounter_struct
*icount
);
283 #ifdef CONFIG_CONSOLE_POLL
284 int (*poll_init
)(struct tty_driver
*driver
, int line
, char *options
);
285 int (*poll_get_char
)(struct tty_driver
*driver
, int line
);
286 void (*poll_put_char
)(struct tty_driver
*driver
, int line
, char ch
);
288 const struct file_operations
*proc_fops
;
292 int magic
; /* magic number for this structure */
293 struct kref kref
; /* Reference management */
295 struct module
*owner
;
296 const char *driver_name
;
298 int name_base
; /* offset of printed name */
299 int major
; /* major device number */
300 int minor_start
; /* start of minor device number */
301 int minor_num
; /* number of *possible* devices */
302 int num
; /* number of devices allocated */
303 short type
; /* type of tty driver */
304 short subtype
; /* subtype of tty driver */
305 struct ktermios init_termios
; /* Initial termios */
306 int flags
; /* tty driver flags */
307 struct proc_dir_entry
*proc_entry
; /* /proc fs entry */
308 struct tty_driver
*other
; /* only used for the PTY driver */
311 * Pointer to the tty data structures
313 struct tty_struct
**ttys
;
314 struct ktermios
**termios
;
315 struct ktermios
**termios_locked
;
322 const struct tty_operations
*ops
;
323 struct list_head tty_drivers
;
326 extern struct list_head tty_drivers
;
328 extern struct tty_driver
*alloc_tty_driver(int lines
);
329 extern void put_tty_driver(struct tty_driver
*driver
);
330 extern void tty_set_operations(struct tty_driver
*driver
,
331 const struct tty_operations
*op
);
332 extern struct tty_driver
*tty_find_polling_driver(char *name
, int *line
);
334 extern void tty_driver_kref_put(struct tty_driver
*driver
);
336 static inline struct tty_driver
*tty_driver_kref_get(struct tty_driver
*d
)
342 /* tty driver magic number */
343 #define TTY_DRIVER_MAGIC 0x5402
348 * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the
349 * termios setting when the last process has closed the device.
350 * Used for PTY's, in particular.
352 * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
353 * guarantee never not to set any special character handling
354 * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
355 * !INPCK)). That is, if there is no reason for the driver to
356 * send notifications of parity and break characters up to the
357 * line driver, it won't do so. This allows the line driver to
358 * optimize for this case if this flag is set. (Note that there
359 * is also a promise, if the above case is true, not to signal
362 * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need
363 * to be registered with a call to tty_register_device() when the
364 * device is found in the system and unregistered with a call to
365 * tty_unregister_device() so the devices will be show up
366 * properly in sysfs. If not set, driver->num entries will be
367 * created by the tty core in sysfs when tty_register_driver() is
368 * called. This is to be used by drivers that have tty devices
369 * that can appear and disappear while the main tty driver is
370 * registered with the tty core.
372 * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
373 * use dynamic memory keyed through the devpts filesystem. This
374 * is only applicable to the pty driver.
376 * TTY_DRIVER_HARDWARE_BREAK -- hardware handles break signals. Pass
377 * the requested timeout to the caller instead of using a simple
381 #define TTY_DRIVER_INSTALLED 0x0001
382 #define TTY_DRIVER_RESET_TERMIOS 0x0002
383 #define TTY_DRIVER_REAL_RAW 0x0004
384 #define TTY_DRIVER_DYNAMIC_DEV 0x0008
385 #define TTY_DRIVER_DEVPTS_MEM 0x0010
386 #define TTY_DRIVER_HARDWARE_BREAK 0x0020
388 /* tty driver types */
389 #define TTY_DRIVER_TYPE_SYSTEM 0x0001
390 #define TTY_DRIVER_TYPE_CONSOLE 0x0002
391 #define TTY_DRIVER_TYPE_SERIAL 0x0003
392 #define TTY_DRIVER_TYPE_PTY 0x0004
393 #define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */
394 #define TTY_DRIVER_TYPE_SYSCONS 0x0006
396 /* system subtypes (magic, used by tty_io.c) */
397 #define SYSTEM_TYPE_TTY 0x0001
398 #define SYSTEM_TYPE_CONSOLE 0x0002
399 #define SYSTEM_TYPE_SYSCONS 0x0003
400 #define SYSTEM_TYPE_SYSPTMX 0x0004
402 /* pty subtypes (magic, used by tty_io.c) */
403 #define PTY_TYPE_MASTER 0x0001
404 #define PTY_TYPE_SLAVE 0x0002
406 /* serial subtype definitions */
407 #define SERIAL_TYPE_NORMAL 1
409 #endif /* #ifdef _LINUX_TTY_DRIVER_H */
This page took 0.043174 seconds and 5 git commands to generate.