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1da177e4 LT |
1 | #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 | * | |
99f1fe18 AC |
10 | * 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 | * | |
1da177e4 LT |
18 | * int (*open)(struct tty_struct * tty, struct file * filp); |
19 | * | |
20 | * This routine is called when a particular tty device is opened. | |
21 | * This routine is mandatory; if this routine is not filled in, | |
22 | * the attempted open will fail with ENODEV. | |
f34d7a5b AC |
23 | * |
24 | * Required method. | |
1da177e4 LT |
25 | * |
26 | * void (*close)(struct tty_struct * tty, struct file * filp); | |
27 | * | |
28 | * This routine is called when a particular tty device is closed. | |
29 | * | |
f34d7a5b AC |
30 | * Required method. |
31 | * | |
feebed65 AC |
32 | * void (*shutdown)(struct tty_struct * tty); |
33 | * | |
34 | * This routine is called when a particular tty device is closed for | |
35 | * the last time freeing up the resources. | |
36 | * | |
1da177e4 LT |
37 | * int (*write)(struct tty_struct * tty, |
38 | * const unsigned char *buf, int count); | |
39 | * | |
40 | * This routine is called by the kernel to write a series of | |
41 | * characters to the tty device. The characters may come from | |
42 | * user space or kernel space. This routine will return the | |
36c7343b | 43 | * number of characters actually accepted for writing. |
1da177e4 | 44 | * |
f34d7a5b AC |
45 | * Optional: Required for writable devices. |
46 | * | |
47 | * int (*put_char)(struct tty_struct *tty, unsigned char ch); | |
1da177e4 LT |
48 | * |
49 | * This routine is called by the kernel to write a single | |
50 | * character to the tty device. If the kernel uses this routine, | |
51 | * it must call the flush_chars() routine (if defined) when it is | |
52 | * done stuffing characters into the driver. If there is no room | |
53 | * in the queue, the character is ignored. | |
54 | * | |
f34d7a5b AC |
55 | * Optional: Kernel will use the write method if not provided. |
56 | * | |
57 | * Note: Do not call this function directly, call tty_put_char | |
58 | * | |
1da177e4 LT |
59 | * void (*flush_chars)(struct tty_struct *tty); |
60 | * | |
61 | * This routine is called by the kernel after it has written a | |
62 | * series of characters to the tty device using put_char(). | |
f34d7a5b AC |
63 | * |
64 | * Optional: | |
65 | * | |
66 | * Note: Do not call this function directly, call tty_driver_flush_chars | |
1da177e4 LT |
67 | * |
68 | * int (*write_room)(struct tty_struct *tty); | |
69 | * | |
70 | * This routine returns the numbers of characters the tty driver | |
71 | * will accept for queuing to be written. This number is subject | |
72 | * to change as output buffers get emptied, or if the output flow | |
73 | * control is acted. | |
f34d7a5b AC |
74 | * |
75 | * Required if write method is provided else not needed. | |
76 | * | |
77 | * Note: Do not call this function directly, call tty_write_room | |
1da177e4 LT |
78 | * |
79 | * int (*ioctl)(struct tty_struct *tty, struct file * file, | |
80 | * unsigned int cmd, unsigned long arg); | |
81 | * | |
82 | * This routine allows the tty driver to implement | |
83 | * device-specific ioctl's. If the ioctl number passed in cmd | |
84 | * is not recognized by the driver, it should return ENOIOCTLCMD. | |
e10cc1df | 85 | * |
f34d7a5b AC |
86 | * Optional |
87 | * | |
e10cc1df PF |
88 | * long (*compat_ioctl)(struct tty_struct *tty, struct file * file, |
89 | * unsigned int cmd, unsigned long arg); | |
90 | * | |
91 | * implement ioctl processing for 32 bit process on 64 bit system | |
f34d7a5b AC |
92 | * |
93 | * Optional | |
1da177e4 | 94 | * |
edc6afc5 | 95 | * void (*set_termios)(struct tty_struct *tty, struct ktermios * old); |
1da177e4 LT |
96 | * |
97 | * This routine allows the tty driver to be notified when | |
f34d7a5b AC |
98 | * device's termios settings have changed. |
99 | * | |
100 | * Optional: Called under the termios lock | |
101 | * | |
1da177e4 LT |
102 | * |
103 | * void (*set_ldisc)(struct tty_struct *tty); | |
104 | * | |
105 | * This routine allows the tty driver to be notified when the | |
106 | * device's termios settings have changed. | |
f34d7a5b AC |
107 | * |
108 | * Optional: Called under BKL (currently) | |
1da177e4 LT |
109 | * |
110 | * void (*throttle)(struct tty_struct * tty); | |
111 | * | |
112 | * This routine notifies the tty driver that input buffers for | |
113 | * the line discipline are close to full, and it should somehow | |
114 | * signal that no more characters should be sent to the tty. | |
39c2e60f AC |
115 | * |
116 | * Optional: Always invoke via tty_throttle(); | |
1da177e4 LT |
117 | * |
118 | * void (*unthrottle)(struct tty_struct * tty); | |
119 | * | |
120 | * This routine notifies the tty drivers that it should signals | |
121 | * that characters can now be sent to the tty without fear of | |
122 | * overrunning the input buffers of the line disciplines. | |
123 | * | |
39c2e60f AC |
124 | * Optional: Always invoke via tty_unthrottle(); |
125 | * | |
1da177e4 LT |
126 | * void (*stop)(struct tty_struct *tty); |
127 | * | |
128 | * This routine notifies the tty driver that it should stop | |
129 | * outputting characters to the tty device. | |
f34d7a5b AC |
130 | * |
131 | * Optional: | |
132 | * | |
133 | * Note: Call stop_tty not this method. | |
1da177e4 LT |
134 | * |
135 | * void (*start)(struct tty_struct *tty); | |
136 | * | |
137 | * This routine notifies the tty driver that it resume sending | |
138 | * characters to the tty device. | |
f34d7a5b AC |
139 | * |
140 | * Optional: | |
141 | * | |
142 | * Note: Call start_tty not this method. | |
1da177e4 LT |
143 | * |
144 | * void (*hangup)(struct tty_struct *tty); | |
145 | * | |
146 | * This routine notifies the tty driver that it should hangup the | |
147 | * tty device. | |
148 | * | |
36c7343b | 149 | * Optional: |
f34d7a5b | 150 | * |
9e98966c | 151 | * int (*break_ctl)(struct tty_stuct *tty, int state); |
1da177e4 LT |
152 | * |
153 | * This optional routine requests the tty driver to turn on or | |
154 | * off BREAK status on the RS-232 port. If state is -1, | |
155 | * then the BREAK status should be turned on; if state is 0, then | |
156 | * BREAK should be turned off. | |
157 | * | |
158 | * If this routine is implemented, the high-level tty driver will | |
159 | * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK, | |
f34d7a5b AC |
160 | * TIOCCBRK. |
161 | * | |
9e98966c AC |
162 | * If the driver sets TTY_DRIVER_HARDWARE_BREAK then the interface |
163 | * will also be called with actual times and the hardware is expected | |
164 | * to do the delay work itself. 0 and -1 are still used for on/off. | |
165 | * | |
f34d7a5b | 166 | * Optional: Required for TCSBRK/BRKP/etc handling. |
1da177e4 LT |
167 | * |
168 | * void (*wait_until_sent)(struct tty_struct *tty, int timeout); | |
169 | * | |
170 | * This routine waits until the device has written out all of the | |
171 | * characters in its transmitter FIFO. | |
172 | * | |
f34d7a5b AC |
173 | * Optional: If not provided the device is assumed to have no FIFO |
174 | * | |
175 | * Note: Usually correct to call tty_wait_until_sent | |
176 | * | |
1da177e4 LT |
177 | * void (*send_xchar)(struct tty_struct *tty, char ch); |
178 | * | |
179 | * This routine is used to send a high-priority XON/XOFF | |
180 | * character to the device. | |
f34d7a5b AC |
181 | * |
182 | * Optional: If not provided then the write method is called under | |
183 | * the atomic write lock to keep it serialized with the ldisc. | |
8c9a9dd0 AC |
184 | * |
185 | * int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty, | |
186 | * unsigned int rows, unsigned int cols); | |
187 | * | |
188 | * Called when a termios request is issued which changes the | |
189 | * requested terminal geometry. | |
190 | * | |
191 | * Optional: the default action is to update the termios structure | |
192 | * without error. This is usually the correct behaviour. Drivers should | |
193 | * not force errors here if they are not resizable objects (eg a serial | |
194 | * line). See tty_do_resize() if you need to wrap the standard method | |
195 | * in your own logic - the usual case. | |
1d65b4a0 AC |
196 | * |
197 | * void (*set_termiox)(struct tty_struct *tty, struct termiox *new); | |
198 | * | |
199 | * Called when the device receives a termiox based ioctl. Passes down | |
200 | * the requested data from user space. This method will not be invoked | |
201 | * unless the tty also has a valid tty->termiox pointer. | |
202 | * | |
203 | * Optional: Called under the termios lock | |
1da177e4 LT |
204 | */ |
205 | ||
206 | #include <linux/fs.h> | |
207 | #include <linux/list.h> | |
208 | #include <linux/cdev.h> | |
209 | ||
210 | struct tty_struct; | |
f2d937f3 | 211 | struct tty_driver; |
1da177e4 LT |
212 | |
213 | struct tty_operations { | |
99f1fe18 | 214 | struct tty_struct * (*lookup)(struct tty_driver *driver, int idx); |
1da177e4 LT |
215 | int (*open)(struct tty_struct * tty, struct file * filp); |
216 | void (*close)(struct tty_struct * tty, struct file * filp); | |
feebed65 | 217 | void (*shutdown)(struct tty_struct *tty); |
1da177e4 LT |
218 | int (*write)(struct tty_struct * tty, |
219 | const unsigned char *buf, int count); | |
f34d7a5b | 220 | int (*put_char)(struct tty_struct *tty, unsigned char ch); |
1da177e4 LT |
221 | void (*flush_chars)(struct tty_struct *tty); |
222 | int (*write_room)(struct tty_struct *tty); | |
223 | int (*chars_in_buffer)(struct tty_struct *tty); | |
224 | int (*ioctl)(struct tty_struct *tty, struct file * file, | |
225 | unsigned int cmd, unsigned long arg); | |
e10cc1df PF |
226 | long (*compat_ioctl)(struct tty_struct *tty, struct file * file, |
227 | unsigned int cmd, unsigned long arg); | |
edc6afc5 | 228 | void (*set_termios)(struct tty_struct *tty, struct ktermios * old); |
1da177e4 LT |
229 | void (*throttle)(struct tty_struct * tty); |
230 | void (*unthrottle)(struct tty_struct * tty); | |
231 | void (*stop)(struct tty_struct *tty); | |
232 | void (*start)(struct tty_struct *tty); | |
233 | void (*hangup)(struct tty_struct *tty); | |
9e98966c | 234 | int (*break_ctl)(struct tty_struct *tty, int state); |
1da177e4 LT |
235 | void (*flush_buffer)(struct tty_struct *tty); |
236 | void (*set_ldisc)(struct tty_struct *tty); | |
237 | void (*wait_until_sent)(struct tty_struct *tty, int timeout); | |
238 | void (*send_xchar)(struct tty_struct *tty, char ch); | |
239 | int (*read_proc)(char *page, char **start, off_t off, | |
240 | int count, int *eof, void *data); | |
1da177e4 LT |
241 | int (*tiocmget)(struct tty_struct *tty, struct file *file); |
242 | int (*tiocmset)(struct tty_struct *tty, struct file *file, | |
243 | unsigned int set, unsigned int clear); | |
8c9a9dd0 AC |
244 | int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty, |
245 | struct winsize *ws); | |
1d65b4a0 | 246 | int (*set_termiox)(struct tty_struct *tty, struct termiox *tnew); |
f2d937f3 JW |
247 | #ifdef CONFIG_CONSOLE_POLL |
248 | int (*poll_init)(struct tty_driver *driver, int line, char *options); | |
249 | int (*poll_get_char)(struct tty_driver *driver, int line); | |
250 | void (*poll_put_char)(struct tty_driver *driver, int line, char ch); | |
251 | #endif | |
1da177e4 LT |
252 | }; |
253 | ||
254 | struct tty_driver { | |
255 | int magic; /* magic number for this structure */ | |
7d7b93c1 | 256 | struct kref kref; /* Reference management */ |
1da177e4 LT |
257 | struct cdev cdev; |
258 | struct module *owner; | |
259 | const char *driver_name; | |
1da177e4 LT |
260 | const char *name; |
261 | int name_base; /* offset of printed name */ | |
262 | int major; /* major device number */ | |
263 | int minor_start; /* start of minor device number */ | |
264 | int minor_num; /* number of *possible* devices */ | |
265 | int num; /* number of devices allocated */ | |
266 | short type; /* type of tty driver */ | |
267 | short subtype; /* subtype of tty driver */ | |
edc6afc5 | 268 | struct ktermios init_termios; /* Initial termios */ |
1da177e4 | 269 | int flags; /* tty driver flags */ |
1da177e4 LT |
270 | struct proc_dir_entry *proc_entry; /* /proc fs entry */ |
271 | struct tty_driver *other; /* only used for the PTY driver */ | |
272 | ||
273 | /* | |
274 | * Pointer to the tty data structures | |
275 | */ | |
276 | struct tty_struct **ttys; | |
edc6afc5 AC |
277 | struct ktermios **termios; |
278 | struct ktermios **termios_locked; | |
f34d7a5b AC |
279 | void *driver_state; |
280 | ||
1da177e4 | 281 | /* |
f34d7a5b | 282 | * Driver methods |
1da177e4 | 283 | */ |
1da177e4 | 284 | |
f34d7a5b | 285 | const struct tty_operations *ops; |
1da177e4 LT |
286 | struct list_head tty_drivers; |
287 | }; | |
288 | ||
289 | extern struct list_head tty_drivers; | |
290 | ||
7d7b93c1 AC |
291 | extern struct tty_driver *alloc_tty_driver(int lines); |
292 | extern void put_tty_driver(struct tty_driver *driver); | |
293 | extern void tty_set_operations(struct tty_driver *driver, | |
b68e31d0 | 294 | const struct tty_operations *op); |
f2d937f3 | 295 | extern struct tty_driver *tty_find_polling_driver(char *name, int *line); |
1da177e4 | 296 | |
7d7b93c1 AC |
297 | extern void tty_driver_kref_put(struct tty_driver *driver); |
298 | extern inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d) | |
299 | { | |
300 | kref_get(&d->kref); | |
301 | return d; | |
302 | } | |
303 | ||
1da177e4 LT |
304 | /* tty driver magic number */ |
305 | #define TTY_DRIVER_MAGIC 0x5402 | |
306 | ||
307 | /* | |
308 | * tty driver flags | |
309 | * | |
310 | * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the | |
311 | * termios setting when the last process has closed the device. | |
312 | * Used for PTY's, in particular. | |
313 | * | |
314 | * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will | |
315 | * guarantee never not to set any special character handling | |
316 | * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR || | |
317 | * !INPCK)). That is, if there is no reason for the driver to | |
318 | * send notifications of parity and break characters up to the | |
319 | * line driver, it won't do so. This allows the line driver to | |
320 | * optimize for this case if this flag is set. (Note that there | |
321 | * is also a promise, if the above case is true, not to signal | |
322 | * overruns, either.) | |
323 | * | |
331b8319 GKH |
324 | * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need |
325 | * to be registered with a call to tty_register_driver() when the | |
326 | * device is found in the system and unregistered with a call to | |
327 | * tty_unregister_device() so the devices will be show up | |
328 | * properly in sysfs. If not set, driver->num entries will be | |
329 | * created by the tty core in sysfs when tty_register_driver() is | |
330 | * called. This is to be used by drivers that have tty devices | |
331 | * that can appear and disappear while the main tty driver is | |
332 | * registered with the tty core. | |
1da177e4 LT |
333 | * |
334 | * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead | |
335 | * use dynamic memory keyed through the devpts filesystem. This | |
336 | * is only applicable to the pty driver. | |
9e98966c AC |
337 | * |
338 | * TTY_DRIVER_HARDWARE_BREAK -- hardware handles break signals. Pass | |
339 | * the requested timeout to the caller instead of using a simple | |
340 | * on/off interface. | |
341 | * | |
1da177e4 LT |
342 | */ |
343 | #define TTY_DRIVER_INSTALLED 0x0001 | |
344 | #define TTY_DRIVER_RESET_TERMIOS 0x0002 | |
345 | #define TTY_DRIVER_REAL_RAW 0x0004 | |
331b8319 | 346 | #define TTY_DRIVER_DYNAMIC_DEV 0x0008 |
1da177e4 | 347 | #define TTY_DRIVER_DEVPTS_MEM 0x0010 |
9e98966c | 348 | #define TTY_DRIVER_HARDWARE_BREAK 0x0020 |
1da177e4 LT |
349 | |
350 | /* tty driver types */ | |
351 | #define TTY_DRIVER_TYPE_SYSTEM 0x0001 | |
352 | #define TTY_DRIVER_TYPE_CONSOLE 0x0002 | |
353 | #define TTY_DRIVER_TYPE_SERIAL 0x0003 | |
354 | #define TTY_DRIVER_TYPE_PTY 0x0004 | |
355 | #define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */ | |
356 | #define TTY_DRIVER_TYPE_SYSCONS 0x0006 | |
357 | ||
358 | /* system subtypes (magic, used by tty_io.c) */ | |
359 | #define SYSTEM_TYPE_TTY 0x0001 | |
360 | #define SYSTEM_TYPE_CONSOLE 0x0002 | |
361 | #define SYSTEM_TYPE_SYSCONS 0x0003 | |
362 | #define SYSTEM_TYPE_SYSPTMX 0x0004 | |
363 | ||
364 | /* pty subtypes (magic, used by tty_io.c) */ | |
365 | #define PTY_TYPE_MASTER 0x0001 | |
366 | #define PTY_TYPE_SLAVE 0x0002 | |
367 | ||
368 | /* serial subtype definitions */ | |
369 | #define SERIAL_TYPE_NORMAL 1 | |
370 | ||
371 | #endif /* #ifdef _LINUX_TTY_DRIVER_H */ |