blob: b086779825252b40612062391dad9c67c3912ddf [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_TTY_DRIVER_H
2#define _LINUX_TTY_DRIVER_H
3
4/*
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.
9 *
Alan Cox99f1fe12008-10-13 10:42:00 +010010 * struct tty_struct * (*lookup)(struct tty_driver *self, int idx)
11 *
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!)
15 *
16 * Optional method. Default behaviour is to use the ttys array
17 *
Alan Cox8b0a88d2008-10-13 10:42:19 +010018 * int (*install)(struct tty_driver *self, struct tty_struct *tty)
19 *
20 * Install a new tty into the tty driver internal tables. Used in
21 * conjunction with lookup and remove methods.
22 *
23 * Optional method. Default behaviour is to use the ttys array
24 *
25 * void (*remove)(struct tty_driver *self, struct tty_struct *tty)
26 *
27 * Remove a closed tty from the tty driver internal tables. Used in
28 * conjunction with lookup and remove methods.
29 *
30 * Optional method. Default behaviour is to use the ttys array
31 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 * int (*open)(struct tty_struct * tty, struct file * filp);
33 *
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.
Alan Coxf34d7a52008-04-30 00:54:13 -070037 *
38 * Required method.
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 *
40 * void (*close)(struct tty_struct * tty, struct file * filp);
41 *
42 * This routine is called when a particular tty device is closed.
43 *
Alan Coxf34d7a52008-04-30 00:54:13 -070044 * Required method.
45 *
Alan Coxfeebed62008-10-13 10:41:30 +010046 * void (*shutdown)(struct tty_struct * tty);
47 *
Dave Youngf278a2f2009-09-27 16:00:42 +000048 * This routine is called synchronously when a particular tty device
49 * is closed for the last time freeing up the resources.
50 *
51 *
52 * void (*cleanup)(struct tty_struct * tty);
53 *
54 * This routine is called asynchronously when a particular tty device
55 * is closed for the last time freeing up the resources. This is
56 * actually the second part of shutdown for routines that might sleep.
57 *
Alan Coxfeebed62008-10-13 10:41:30 +010058 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 * int (*write)(struct tty_struct * tty,
60 * const unsigned char *buf, int count);
61 *
62 * This routine is called by the kernel to write a series of
63 * characters to the tty device. The characters may come from
64 * user space or kernel space. This routine will return the
Alan Cox36c73432008-06-23 12:06:52 +010065 * number of characters actually accepted for writing.
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 *
Alan Coxf34d7a52008-04-30 00:54:13 -070067 * Optional: Required for writable devices.
68 *
69 * int (*put_char)(struct tty_struct *tty, unsigned char ch);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 *
71 * This routine is called by the kernel to write a single
72 * character to the tty device. If the kernel uses this routine,
73 * it must call the flush_chars() routine (if defined) when it is
74 * done stuffing characters into the driver. If there is no room
75 * in the queue, the character is ignored.
76 *
Alan Coxf34d7a52008-04-30 00:54:13 -070077 * Optional: Kernel will use the write method if not provided.
78 *
79 * Note: Do not call this function directly, call tty_put_char
80 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 * void (*flush_chars)(struct tty_struct *tty);
82 *
83 * This routine is called by the kernel after it has written a
84 * series of characters to the tty device using put_char().
Alan Coxf34d7a52008-04-30 00:54:13 -070085 *
86 * Optional:
87 *
88 * Note: Do not call this function directly, call tty_driver_flush_chars
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 *
90 * int (*write_room)(struct tty_struct *tty);
91 *
92 * This routine returns the numbers of characters the tty driver
93 * will accept for queuing to be written. This number is subject
94 * to change as output buffers get emptied, or if the output flow
95 * control is acted.
Alan Coxf34d7a52008-04-30 00:54:13 -070096 *
97 * Required if write method is provided else not needed.
98 *
99 * Note: Do not call this function directly, call tty_write_room
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 *
101 * int (*ioctl)(struct tty_struct *tty, struct file * file,
102 * unsigned int cmd, unsigned long arg);
103 *
104 * This routine allows the tty driver to implement
105 * device-specific ioctl's. If the ioctl number passed in cmd
106 * is not recognized by the driver, it should return ENOIOCTLCMD.
Paul Fulghume10cc1d2007-05-10 22:22:50 -0700107 *
Alan Coxf34d7a52008-04-30 00:54:13 -0700108 * Optional
109 *
Paul Fulghume10cc1d2007-05-10 22:22:50 -0700110 * long (*compat_ioctl)(struct tty_struct *tty, struct file * file,
111 * unsigned int cmd, unsigned long arg);
112 *
113 * implement ioctl processing for 32 bit process on 64 bit system
Alan Coxf34d7a52008-04-30 00:54:13 -0700114 *
115 * Optional
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 *
Alan Coxedc6afc2006-12-08 02:38:44 -0800117 * void (*set_termios)(struct tty_struct *tty, struct ktermios * old);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 *
119 * This routine allows the tty driver to be notified when
Alan Coxf34d7a52008-04-30 00:54:13 -0700120 * device's termios settings have changed.
121 *
122 * Optional: Called under the termios lock
123 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 *
125 * void (*set_ldisc)(struct tty_struct *tty);
126 *
127 * This routine allows the tty driver to be notified when the
128 * device's termios settings have changed.
Alan Coxf34d7a52008-04-30 00:54:13 -0700129 *
130 * Optional: Called under BKL (currently)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 *
132 * void (*throttle)(struct tty_struct * tty);
133 *
134 * This routine notifies the tty driver that input buffers for
135 * the line discipline are close to full, and it should somehow
136 * signal that no more characters should be sent to the tty.
Alan Cox39c2e602008-04-30 00:54:18 -0700137 *
Alan Cox38db8972009-06-11 12:44:17 +0100138 * Optional: Always invoke via tty_throttle(), called under the
139 * termios lock.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 *
141 * void (*unthrottle)(struct tty_struct * tty);
142 *
143 * This routine notifies the tty drivers that it should signals
144 * that characters can now be sent to the tty without fear of
145 * overrunning the input buffers of the line disciplines.
146 *
Alan Cox38db8972009-06-11 12:44:17 +0100147 * Optional: Always invoke via tty_unthrottle(), called under the
148 * termios lock.
Alan Cox39c2e602008-04-30 00:54:18 -0700149 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 * void (*stop)(struct tty_struct *tty);
151 *
152 * This routine notifies the tty driver that it should stop
153 * outputting characters to the tty device.
Alan Coxf34d7a52008-04-30 00:54:13 -0700154 *
155 * Optional:
156 *
157 * Note: Call stop_tty not this method.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 *
159 * void (*start)(struct tty_struct *tty);
160 *
161 * This routine notifies the tty driver that it resume sending
162 * characters to the tty device.
Alan Coxf34d7a52008-04-30 00:54:13 -0700163 *
164 * Optional:
165 *
166 * Note: Call start_tty not this method.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 *
168 * void (*hangup)(struct tty_struct *tty);
169 *
170 * This routine notifies the tty driver that it should hangup the
171 * tty device.
172 *
Alan Cox36c73432008-06-23 12:06:52 +0100173 * Optional:
Alan Coxf34d7a52008-04-30 00:54:13 -0700174 *
Alan Cox9e989662008-07-22 11:18:03 +0100175 * int (*break_ctl)(struct tty_stuct *tty, int state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 *
177 * This optional routine requests the tty driver to turn on or
178 * off BREAK status on the RS-232 port. If state is -1,
179 * then the BREAK status should be turned on; if state is 0, then
180 * BREAK should be turned off.
181 *
182 * If this routine is implemented, the high-level tty driver will
183 * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
Alan Coxf34d7a52008-04-30 00:54:13 -0700184 * TIOCCBRK.
185 *
Alan Cox9e989662008-07-22 11:18:03 +0100186 * If the driver sets TTY_DRIVER_HARDWARE_BREAK then the interface
187 * will also be called with actual times and the hardware is expected
188 * to do the delay work itself. 0 and -1 are still used for on/off.
189 *
Alan Coxf34d7a52008-04-30 00:54:13 -0700190 * Optional: Required for TCSBRK/BRKP/etc handling.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 *
192 * void (*wait_until_sent)(struct tty_struct *tty, int timeout);
193 *
194 * This routine waits until the device has written out all of the
195 * characters in its transmitter FIFO.
196 *
Alan Coxf34d7a52008-04-30 00:54:13 -0700197 * Optional: If not provided the device is assumed to have no FIFO
198 *
199 * Note: Usually correct to call tty_wait_until_sent
200 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 * void (*send_xchar)(struct tty_struct *tty, char ch);
202 *
203 * This routine is used to send a high-priority XON/XOFF
204 * character to the device.
Alan Coxf34d7a52008-04-30 00:54:13 -0700205 *
206 * Optional: If not provided then the write method is called under
207 * the atomic write lock to keep it serialized with the ldisc.
Alan Cox8c9a9dd2008-08-15 10:39:38 +0100208 *
Alan Coxfc6f6232009-01-02 13:43:17 +0000209 * int (*resize)(struct tty_struct *tty, struct winsize *ws)
Alan Cox8c9a9dd2008-08-15 10:39:38 +0100210 *
211 * Called when a termios request is issued which changes the
212 * requested terminal geometry.
213 *
214 * Optional: the default action is to update the termios structure
215 * without error. This is usually the correct behaviour. Drivers should
216 * not force errors here if they are not resizable objects (eg a serial
217 * line). See tty_do_resize() if you need to wrap the standard method
218 * in your own logic - the usual case.
Alan Cox1d65b4a2008-10-13 10:38:18 +0100219 *
220 * void (*set_termiox)(struct tty_struct *tty, struct termiox *new);
221 *
222 * Called when the device receives a termiox based ioctl. Passes down
223 * the requested data from user space. This method will not be invoked
224 * unless the tty also has a valid tty->termiox pointer.
225 *
226 * Optional: Called under the termios lock
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 */
228
229#include <linux/fs.h>
230#include <linux/list.h>
231#include <linux/cdev.h>
232
233struct tty_struct;
Jason Wesself2d937f2008-04-17 20:05:37 +0200234struct tty_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
236struct tty_operations {
Sukadev Bhattiprolu15f1a632008-10-13 10:42:59 +0100237 struct tty_struct * (*lookup)(struct tty_driver *driver,
238 struct inode *inode, int idx);
Alan Cox8b0a88d2008-10-13 10:42:19 +0100239 int (*install)(struct tty_driver *driver, struct tty_struct *tty);
240 void (*remove)(struct tty_driver *driver, struct tty_struct *tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 int (*open)(struct tty_struct * tty, struct file * filp);
242 void (*close)(struct tty_struct * tty, struct file * filp);
Alan Coxfeebed62008-10-13 10:41:30 +0100243 void (*shutdown)(struct tty_struct *tty);
Dave Youngf278a2f2009-09-27 16:00:42 +0000244 void (*cleanup)(struct tty_struct *tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 int (*write)(struct tty_struct * tty,
246 const unsigned char *buf, int count);
Alan Coxf34d7a52008-04-30 00:54:13 -0700247 int (*put_char)(struct tty_struct *tty, unsigned char ch);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 void (*flush_chars)(struct tty_struct *tty);
249 int (*write_room)(struct tty_struct *tty);
250 int (*chars_in_buffer)(struct tty_struct *tty);
251 int (*ioctl)(struct tty_struct *tty, struct file * file,
252 unsigned int cmd, unsigned long arg);
Paul Fulghume10cc1d2007-05-10 22:22:50 -0700253 long (*compat_ioctl)(struct tty_struct *tty, struct file * file,
254 unsigned int cmd, unsigned long arg);
Alan Coxedc6afc2006-12-08 02:38:44 -0800255 void (*set_termios)(struct tty_struct *tty, struct ktermios * old);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 void (*throttle)(struct tty_struct * tty);
257 void (*unthrottle)(struct tty_struct * tty);
258 void (*stop)(struct tty_struct *tty);
259 void (*start)(struct tty_struct *tty);
260 void (*hangup)(struct tty_struct *tty);
Alan Cox9e989662008-07-22 11:18:03 +0100261 int (*break_ctl)(struct tty_struct *tty, int state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 void (*flush_buffer)(struct tty_struct *tty);
263 void (*set_ldisc)(struct tty_struct *tty);
264 void (*wait_until_sent)(struct tty_struct *tty, int timeout);
265 void (*send_xchar)(struct tty_struct *tty, char ch);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 int (*tiocmget)(struct tty_struct *tty, struct file *file);
267 int (*tiocmset)(struct tty_struct *tty, struct file *file,
268 unsigned int set, unsigned int clear);
Alan Coxfc6f6232009-01-02 13:43:17 +0000269 int (*resize)(struct tty_struct *tty, struct winsize *ws);
Alan Cox1d65b4a2008-10-13 10:38:18 +0100270 int (*set_termiox)(struct tty_struct *tty, struct termiox *tnew);
Jason Wesself2d937f2008-04-17 20:05:37 +0200271#ifdef CONFIG_CONSOLE_POLL
272 int (*poll_init)(struct tty_driver *driver, int line, char *options);
273 int (*poll_get_char)(struct tty_driver *driver, int line);
274 void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
275#endif
Alexey Dobriyanae149b62009-03-31 15:19:15 -0700276 const struct file_operations *proc_fops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277};
278
279struct tty_driver {
280 int magic; /* magic number for this structure */
Alan Cox7d7b93c2008-10-13 10:42:09 +0100281 struct kref kref; /* Reference management */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 struct cdev cdev;
283 struct module *owner;
284 const char *driver_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 const char *name;
286 int name_base; /* offset of printed name */
287 int major; /* major device number */
288 int minor_start; /* start of minor device number */
289 int minor_num; /* number of *possible* devices */
290 int num; /* number of devices allocated */
291 short type; /* type of tty driver */
292 short subtype; /* subtype of tty driver */
Alan Coxedc6afc2006-12-08 02:38:44 -0800293 struct ktermios init_termios; /* Initial termios */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 int flags; /* tty driver flags */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 struct proc_dir_entry *proc_entry; /* /proc fs entry */
296 struct tty_driver *other; /* only used for the PTY driver */
297
298 /*
299 * Pointer to the tty data structures
300 */
301 struct tty_struct **ttys;
Alan Coxedc6afc2006-12-08 02:38:44 -0800302 struct ktermios **termios;
303 struct ktermios **termios_locked;
Alan Coxf34d7a52008-04-30 00:54:13 -0700304 void *driver_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
Alan Coxf34d7a52008-04-30 00:54:13 -0700306 /*
307 * Driver methods
308 */
309
310 const struct tty_operations *ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 struct list_head tty_drivers;
312};
313
314extern struct list_head tty_drivers;
315
Alan Cox7d7b93c2008-10-13 10:42:09 +0100316extern struct tty_driver *alloc_tty_driver(int lines);
317extern void put_tty_driver(struct tty_driver *driver);
318extern void tty_set_operations(struct tty_driver *driver,
Jeff Dikeb68e31d2006-10-02 02:17:18 -0700319 const struct tty_operations *op);
Jason Wesself2d937f2008-04-17 20:05:37 +0200320extern struct tty_driver *tty_find_polling_driver(char *name, int *line);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321
Alan Cox7d7b93c2008-10-13 10:42:09 +0100322extern void tty_driver_kref_put(struct tty_driver *driver);
Adrian Bunkf786ddd2009-04-07 16:48:07 +0100323
324static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d)
Alan Cox7d7b93c2008-10-13 10:42:09 +0100325{
326 kref_get(&d->kref);
327 return d;
328}
329
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330/* tty driver magic number */
331#define TTY_DRIVER_MAGIC 0x5402
332
333/*
334 * tty driver flags
335 *
336 * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the
337 * termios setting when the last process has closed the device.
338 * Used for PTY's, in particular.
339 *
340 * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
341 * guarantee never not to set any special character handling
342 * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
343 * !INPCK)). That is, if there is no reason for the driver to
344 * send notifications of parity and break characters up to the
345 * line driver, it won't do so. This allows the line driver to
346 * optimize for this case if this flag is set. (Note that there
347 * is also a promise, if the above case is true, not to signal
348 * overruns, either.)
349 *
Greg Kroah-Hartman331b8312005-06-20 21:15:16 -0700350 * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need
351 * to be registered with a call to tty_register_driver() when the
352 * device is found in the system and unregistered with a call to
353 * tty_unregister_device() so the devices will be show up
354 * properly in sysfs. If not set, driver->num entries will be
355 * created by the tty core in sysfs when tty_register_driver() is
356 * called. This is to be used by drivers that have tty devices
357 * that can appear and disappear while the main tty driver is
358 * registered with the tty core.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 *
360 * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
361 * use dynamic memory keyed through the devpts filesystem. This
362 * is only applicable to the pty driver.
Alan Cox9e989662008-07-22 11:18:03 +0100363 *
364 * TTY_DRIVER_HARDWARE_BREAK -- hardware handles break signals. Pass
365 * the requested timeout to the caller instead of using a simple
366 * on/off interface.
367 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 */
369#define TTY_DRIVER_INSTALLED 0x0001
370#define TTY_DRIVER_RESET_TERMIOS 0x0002
371#define TTY_DRIVER_REAL_RAW 0x0004
Greg Kroah-Hartman331b8312005-06-20 21:15:16 -0700372#define TTY_DRIVER_DYNAMIC_DEV 0x0008
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373#define TTY_DRIVER_DEVPTS_MEM 0x0010
Alan Cox9e989662008-07-22 11:18:03 +0100374#define TTY_DRIVER_HARDWARE_BREAK 0x0020
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375
376/* tty driver types */
377#define TTY_DRIVER_TYPE_SYSTEM 0x0001
378#define TTY_DRIVER_TYPE_CONSOLE 0x0002
379#define TTY_DRIVER_TYPE_SERIAL 0x0003
380#define TTY_DRIVER_TYPE_PTY 0x0004
381#define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */
382#define TTY_DRIVER_TYPE_SYSCONS 0x0006
383
384/* system subtypes (magic, used by tty_io.c) */
385#define SYSTEM_TYPE_TTY 0x0001
386#define SYSTEM_TYPE_CONSOLE 0x0002
387#define SYSTEM_TYPE_SYSCONS 0x0003
388#define SYSTEM_TYPE_SYSPTMX 0x0004
389
390/* pty subtypes (magic, used by tty_io.c) */
391#define PTY_TYPE_MASTER 0x0001
392#define PTY_TYPE_SLAVE 0x0002
393
394/* serial subtype definitions */
395#define SERIAL_TYPE_NORMAL 1
396
397#endif /* #ifdef _LINUX_TTY_DRIVER_H */