Linux kernel mirror (for testing)
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linux
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 *
10 * int (*open)(struct tty_struct * tty, struct file * filp);
11 *
12 * This routine is called when a particular tty device is opened.
13 * This routine is mandatory; if this routine is not filled in,
14 * the attempted open will fail with ENODEV.
15 *
16 * void (*close)(struct tty_struct * tty, struct file * filp);
17 *
18 * This routine is called when a particular tty device is closed.
19 *
20 * int (*write)(struct tty_struct * tty,
21 * const unsigned char *buf, int count);
22 *
23 * This routine is called by the kernel to write a series of
24 * characters to the tty device. The characters may come from
25 * user space or kernel space. This routine will return the
26 * number of characters actually accepted for writing. This
27 * routine is mandatory.
28 *
29 * void (*put_char)(struct tty_struct *tty, unsigned char ch);
30 *
31 * This routine is called by the kernel to write a single
32 * character to the tty device. If the kernel uses this routine,
33 * it must call the flush_chars() routine (if defined) when it is
34 * done stuffing characters into the driver. If there is no room
35 * in the queue, the character is ignored.
36 *
37 * void (*flush_chars)(struct tty_struct *tty);
38 *
39 * This routine is called by the kernel after it has written a
40 * series of characters to the tty device using put_char().
41 *
42 * int (*write_room)(struct tty_struct *tty);
43 *
44 * This routine returns the numbers of characters the tty driver
45 * will accept for queuing to be written. This number is subject
46 * to change as output buffers get emptied, or if the output flow
47 * control is acted.
48 *
49 * int (*ioctl)(struct tty_struct *tty, struct file * file,
50 * unsigned int cmd, unsigned long arg);
51 *
52 * This routine allows the tty driver to implement
53 * device-specific ioctl's. If the ioctl number passed in cmd
54 * is not recognized by the driver, it should return ENOIOCTLCMD.
55 *
56 * void (*set_termios)(struct tty_struct *tty, struct termios * old);
57 *
58 * This routine allows the tty driver to be notified when
59 * device's termios settings have changed. Note that a
60 * well-designed tty driver should be prepared to accept the case
61 * where old == NULL, and try to do something rational.
62 *
63 * void (*set_ldisc)(struct tty_struct *tty);
64 *
65 * This routine allows the tty driver to be notified when the
66 * device's termios settings have changed.
67 *
68 * void (*throttle)(struct tty_struct * tty);
69 *
70 * This routine notifies the tty driver that input buffers for
71 * the line discipline are close to full, and it should somehow
72 * signal that no more characters should be sent to the tty.
73 *
74 * void (*unthrottle)(struct tty_struct * tty);
75 *
76 * This routine notifies the tty drivers that it should signals
77 * that characters can now be sent to the tty without fear of
78 * overrunning the input buffers of the line disciplines.
79 *
80 * void (*stop)(struct tty_struct *tty);
81 *
82 * This routine notifies the tty driver that it should stop
83 * outputting characters to the tty device.
84 *
85 * void (*start)(struct tty_struct *tty);
86 *
87 * This routine notifies the tty driver that it resume sending
88 * characters to the tty device.
89 *
90 * void (*hangup)(struct tty_struct *tty);
91 *
92 * This routine notifies the tty driver that it should hangup the
93 * tty device.
94 *
95 * void (*break_ctl)(struct tty_stuct *tty, int state);
96 *
97 * This optional routine requests the tty driver to turn on or
98 * off BREAK status on the RS-232 port. If state is -1,
99 * then the BREAK status should be turned on; if state is 0, then
100 * BREAK should be turned off.
101 *
102 * If this routine is implemented, the high-level tty driver will
103 * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
104 * TIOCCBRK. Otherwise, these ioctls will be passed down to the
105 * driver to handle.
106 *
107 * void (*wait_until_sent)(struct tty_struct *tty, int timeout);
108 *
109 * This routine waits until the device has written out all of the
110 * characters in its transmitter FIFO.
111 *
112 * void (*send_xchar)(struct tty_struct *tty, char ch);
113 *
114 * This routine is used to send a high-priority XON/XOFF
115 * character to the device.
116 */
117
118#include <linux/fs.h>
119#include <linux/list.h>
120#include <linux/cdev.h>
121
122struct tty_struct;
123
124struct tty_operations {
125 int (*open)(struct tty_struct * tty, struct file * filp);
126 void (*close)(struct tty_struct * tty, struct file * filp);
127 int (*write)(struct tty_struct * tty,
128 const unsigned char *buf, int count);
129 void (*put_char)(struct tty_struct *tty, unsigned char ch);
130 void (*flush_chars)(struct tty_struct *tty);
131 int (*write_room)(struct tty_struct *tty);
132 int (*chars_in_buffer)(struct tty_struct *tty);
133 int (*ioctl)(struct tty_struct *tty, struct file * file,
134 unsigned int cmd, unsigned long arg);
135 void (*set_termios)(struct tty_struct *tty, struct termios * old);
136 void (*throttle)(struct tty_struct * tty);
137 void (*unthrottle)(struct tty_struct * tty);
138 void (*stop)(struct tty_struct *tty);
139 void (*start)(struct tty_struct *tty);
140 void (*hangup)(struct tty_struct *tty);
141 void (*break_ctl)(struct tty_struct *tty, int state);
142 void (*flush_buffer)(struct tty_struct *tty);
143 void (*set_ldisc)(struct tty_struct *tty);
144 void (*wait_until_sent)(struct tty_struct *tty, int timeout);
145 void (*send_xchar)(struct tty_struct *tty, char ch);
146 int (*read_proc)(char *page, char **start, off_t off,
147 int count, int *eof, void *data);
148 int (*write_proc)(struct file *file, const char __user *buffer,
149 unsigned long count, void *data);
150 int (*tiocmget)(struct tty_struct *tty, struct file *file);
151 int (*tiocmset)(struct tty_struct *tty, struct file *file,
152 unsigned int set, unsigned int clear);
153};
154
155struct tty_driver {
156 int magic; /* magic number for this structure */
157 struct cdev cdev;
158 struct module *owner;
159 const char *driver_name;
160 const char *name;
161 int name_base; /* offset of printed name */
162 int major; /* major device number */
163 int minor_start; /* start of minor device number */
164 int minor_num; /* number of *possible* devices */
165 int num; /* number of devices allocated */
166 short type; /* type of tty driver */
167 short subtype; /* subtype of tty driver */
168 struct termios init_termios; /* Initial termios */
169 int flags; /* tty driver flags */
170 int refcount; /* for loadable tty drivers */
171 struct proc_dir_entry *proc_entry; /* /proc fs entry */
172 struct tty_driver *other; /* only used for the PTY driver */
173
174 /*
175 * Pointer to the tty data structures
176 */
177 struct tty_struct **ttys;
178 struct termios **termios;
179 struct termios **termios_locked;
180 void *driver_state; /* only used for the PTY driver */
181
182 /*
183 * Interface routines from the upper tty layer to the tty
184 * driver. Will be replaced with struct tty_operations.
185 */
186 int (*open)(struct tty_struct * tty, struct file * filp);
187 void (*close)(struct tty_struct * tty, struct file * filp);
188 int (*write)(struct tty_struct * tty,
189 const unsigned char *buf, int count);
190 void (*put_char)(struct tty_struct *tty, unsigned char ch);
191 void (*flush_chars)(struct tty_struct *tty);
192 int (*write_room)(struct tty_struct *tty);
193 int (*chars_in_buffer)(struct tty_struct *tty);
194 int (*ioctl)(struct tty_struct *tty, struct file * file,
195 unsigned int cmd, unsigned long arg);
196 void (*set_termios)(struct tty_struct *tty, struct termios * old);
197 void (*throttle)(struct tty_struct * tty);
198 void (*unthrottle)(struct tty_struct * tty);
199 void (*stop)(struct tty_struct *tty);
200 void (*start)(struct tty_struct *tty);
201 void (*hangup)(struct tty_struct *tty);
202 void (*break_ctl)(struct tty_struct *tty, int state);
203 void (*flush_buffer)(struct tty_struct *tty);
204 void (*set_ldisc)(struct tty_struct *tty);
205 void (*wait_until_sent)(struct tty_struct *tty, int timeout);
206 void (*send_xchar)(struct tty_struct *tty, char ch);
207 int (*read_proc)(char *page, char **start, off_t off,
208 int count, int *eof, void *data);
209 int (*write_proc)(struct file *file, const char __user *buffer,
210 unsigned long count, void *data);
211 int (*tiocmget)(struct tty_struct *tty, struct file *file);
212 int (*tiocmset)(struct tty_struct *tty, struct file *file,
213 unsigned int set, unsigned int clear);
214
215 struct list_head tty_drivers;
216};
217
218extern struct list_head tty_drivers;
219
220struct tty_driver *alloc_tty_driver(int lines);
221void put_tty_driver(struct tty_driver *driver);
222void tty_set_operations(struct tty_driver *driver,
223 const struct tty_operations *op);
224
225/* tty driver magic number */
226#define TTY_DRIVER_MAGIC 0x5402
227
228/*
229 * tty driver flags
230 *
231 * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the
232 * termios setting when the last process has closed the device.
233 * Used for PTY's, in particular.
234 *
235 * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
236 * guarantee never not to set any special character handling
237 * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
238 * !INPCK)). That is, if there is no reason for the driver to
239 * send notifications of parity and break characters up to the
240 * line driver, it won't do so. This allows the line driver to
241 * optimize for this case if this flag is set. (Note that there
242 * is also a promise, if the above case is true, not to signal
243 * overruns, either.)
244 *
245 * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need
246 * to be registered with a call to tty_register_driver() when the
247 * device is found in the system and unregistered with a call to
248 * tty_unregister_device() so the devices will be show up
249 * properly in sysfs. If not set, driver->num entries will be
250 * created by the tty core in sysfs when tty_register_driver() is
251 * called. This is to be used by drivers that have tty devices
252 * that can appear and disappear while the main tty driver is
253 * registered with the tty core.
254 *
255 * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
256 * use dynamic memory keyed through the devpts filesystem. This
257 * is only applicable to the pty driver.
258 */
259#define TTY_DRIVER_INSTALLED 0x0001
260#define TTY_DRIVER_RESET_TERMIOS 0x0002
261#define TTY_DRIVER_REAL_RAW 0x0004
262#define TTY_DRIVER_DYNAMIC_DEV 0x0008
263#define TTY_DRIVER_DEVPTS_MEM 0x0010
264
265/* tty driver types */
266#define TTY_DRIVER_TYPE_SYSTEM 0x0001
267#define TTY_DRIVER_TYPE_CONSOLE 0x0002
268#define TTY_DRIVER_TYPE_SERIAL 0x0003
269#define TTY_DRIVER_TYPE_PTY 0x0004
270#define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */
271#define TTY_DRIVER_TYPE_SYSCONS 0x0006
272
273/* system subtypes (magic, used by tty_io.c) */
274#define SYSTEM_TYPE_TTY 0x0001
275#define SYSTEM_TYPE_CONSOLE 0x0002
276#define SYSTEM_TYPE_SYSCONS 0x0003
277#define SYSTEM_TYPE_SYSPTMX 0x0004
278
279/* pty subtypes (magic, used by tty_io.c) */
280#define PTY_TYPE_MASTER 0x0001
281#define PTY_TYPE_SLAVE 0x0002
282
283/* serial subtype definitions */
284#define SERIAL_TYPE_NORMAL 1
285
286#endif /* #ifdef _LINUX_TTY_DRIVER_H */