tty.h revision f21ec3d2d46e5f2ffc06f31fe2704fdcea7a58f3
1#ifndef _LINUX_TTY_H
2#define _LINUX_TTY_H
3
4/*
5 * 'tty.h' defines some structures used by tty_io.c and some defines.
6 */
7
8#define NR_LDISCS		30
9
10/* line disciplines */
11#define N_TTY		0
12#define N_SLIP		1
13#define N_MOUSE		2
14#define N_PPP		3
15#define N_STRIP		4
16#define N_AX25		5
17#define N_X25		6	/* X.25 async */
18#define N_6PACK		7
19#define N_MASC		8	/* Reserved for Mobitex module <kaz@cafe.net> */
20#define N_R3964		9	/* Reserved for Simatic R3964 module */
21#define N_PROFIBUS_FDL	10	/* Reserved for Profibus */
22#define N_IRDA		11	/* Linux IrDa - http://irda.sourceforge.net/ */
23#define N_SMSBLOCK	12	/* SMS block mode - for talking to GSM data */
24				/* cards about SMS messages */
25#define N_HDLC		13	/* synchronous HDLC */
26#define N_SYNC_PPP	14	/* synchronous PPP */
27#define N_HCI		15	/* Bluetooth HCI UART */
28#define N_GIGASET_M101	16	/* Siemens Gigaset M101 serial DECT adapter */
29#define N_SLCAN		17	/* Serial / USB serial CAN Adaptors */
30#define N_PPS		18	/* Pulse per Second */
31#define N_V253		19	/* Codec control over voice modem */
32#define N_CAIF		20      /* CAIF protocol for talking to modems */
33#define N_GSM0710	21	/* GSM 0710 Mux */
34#define N_TI_WL		22	/* for TI's WL BT, FM, GPS combo chips */
35#define N_TRACESINK	23	/* Trace data routing for MIPI P1149.7 */
36#define N_TRACEROUTER	24	/* Trace data routing for MIPI P1149.7 */
37
38#ifdef __KERNEL__
39#include <linux/fs.h>
40#include <linux/major.h>
41#include <linux/termios.h>
42#include <linux/workqueue.h>
43#include <linux/tty_driver.h>
44#include <linux/tty_ldisc.h>
45#include <linux/mutex.h>
46#include <linux/tty_flags.h>
47
48
49
50/*
51 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
52 * hardcoded at present.)
53 */
54#define NR_UNIX98_PTY_DEFAULT	4096      /* Default maximum for Unix98 ptys */
55#define NR_UNIX98_PTY_RESERVE	1024	  /* Default reserve for main devpts */
56#define NR_UNIX98_PTY_MAX	(1 << MINORBITS) /* Absolute limit */
57
58/*
59 * This character is the same as _POSIX_VDISABLE: it cannot be used as
60 * a c_cc[] character, but indicates that a particular special character
61 * isn't in use (eg VINTR has no character etc)
62 */
63#define __DISABLED_CHAR '\0'
64
65struct tty_buffer {
66	struct tty_buffer *next;
67	char *char_buf_ptr;
68	unsigned char *flag_buf_ptr;
69	int used;
70	int size;
71	int commit;
72	int read;
73	/* Data points here */
74	unsigned long data[0];
75};
76
77/*
78 * We default to dicing tty buffer allocations to this many characters
79 * in order to avoid multiple page allocations. We know the size of
80 * tty_buffer itself but it must also be taken into account that the
81 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
82 * logic this must match
83 */
84
85#define TTY_BUFFER_PAGE	(((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
86
87
88struct tty_bufhead {
89	struct work_struct work;
90	spinlock_t lock;
91	struct tty_buffer *head;	/* Queue head */
92	struct tty_buffer *tail;	/* Active buffer */
93	struct tty_buffer *free;	/* Free queue head */
94	int memory_used;		/* Buffer space used excluding
95								free queue */
96};
97/*
98 * When a break, frame error, or parity error happens, these codes are
99 * stuffed into the flags buffer.
100 */
101#define TTY_NORMAL	0
102#define TTY_BREAK	1
103#define TTY_FRAME	2
104#define TTY_PARITY	3
105#define TTY_OVERRUN	4
106
107#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
108#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
109#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
110#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
111#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
112#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
113#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
114#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
115#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
116#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
117#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
118#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
119#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
120#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
121#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
122#define LNEXT_CHAR(tty)	((tty)->termios.c_cc[VLNEXT])
123#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
124
125#define _I_FLAG(tty, f)	((tty)->termios.c_iflag & (f))
126#define _O_FLAG(tty, f)	((tty)->termios.c_oflag & (f))
127#define _C_FLAG(tty, f)	((tty)->termios.c_cflag & (f))
128#define _L_FLAG(tty, f)	((tty)->termios.c_lflag & (f))
129
130#define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
131#define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
132#define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
133#define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
134#define I_INPCK(tty)	_I_FLAG((tty), INPCK)
135#define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
136#define I_INLCR(tty)	_I_FLAG((tty), INLCR)
137#define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
138#define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
139#define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
140#define I_IXON(tty)	_I_FLAG((tty), IXON)
141#define I_IXANY(tty)	_I_FLAG((tty), IXANY)
142#define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
143#define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
144#define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
145
146#define O_OPOST(tty)	_O_FLAG((tty), OPOST)
147#define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
148#define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
149#define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
150#define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
151#define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
152#define O_OFILL(tty)	_O_FLAG((tty), OFILL)
153#define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
154#define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
155#define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
156#define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
157#define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
158#define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
159#define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
160
161#define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
162#define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
163#define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
164#define C_CREAD(tty)	_C_FLAG((tty), CREAD)
165#define C_PARENB(tty)	_C_FLAG((tty), PARENB)
166#define C_PARODD(tty)	_C_FLAG((tty), PARODD)
167#define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
168#define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
169#define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
170#define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
171
172#define L_ISIG(tty)	_L_FLAG((tty), ISIG)
173#define L_ICANON(tty)	_L_FLAG((tty), ICANON)
174#define L_XCASE(tty)	_L_FLAG((tty), XCASE)
175#define L_ECHO(tty)	_L_FLAG((tty), ECHO)
176#define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
177#define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
178#define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
179#define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
180#define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
181#define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
182#define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
183#define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
184#define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
185#define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
186#define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
187#define L_EXTPROC(tty)	_L_FLAG((tty), EXTPROC)
188
189struct device;
190struct signal_struct;
191
192/*
193 * Port level information. Each device keeps its own port level information
194 * so provide a common structure for those ports wanting to use common support
195 * routines.
196 *
197 * The tty port has a different lifetime to the tty so must be kept apart.
198 * In addition be careful as tty -> port mappings are valid for the life
199 * of the tty object but in many cases port -> tty mappings are valid only
200 * until a hangup so don't use the wrong path.
201 */
202
203struct tty_port;
204
205struct tty_port_operations {
206	/* Return 1 if the carrier is raised */
207	int (*carrier_raised)(struct tty_port *port);
208	/* Control the DTR line */
209	void (*dtr_rts)(struct tty_port *port, int raise);
210	/* Called when the last close completes or a hangup finishes
211	   IFF the port was initialized. Do not use to free resources. Called
212	   under the port mutex to serialize against activate/shutdowns */
213	void (*shutdown)(struct tty_port *port);
214	void (*drop)(struct tty_port *port);
215	/* Called under the port mutex from tty_port_open, serialized using
216	   the port mutex */
217        /* FIXME: long term getting the tty argument *out* of this would be
218           good for consoles */
219	int (*activate)(struct tty_port *port, struct tty_struct *tty);
220	/* Called on the final put of a port */
221	void (*destruct)(struct tty_port *port);
222};
223
224struct tty_port {
225	struct tty_struct	*tty;		/* Back pointer */
226	const struct tty_port_operations *ops;	/* Port operations */
227	spinlock_t		lock;		/* Lock protecting tty field */
228	int			blocked_open;	/* Waiting to open */
229	int			count;		/* Usage count */
230	wait_queue_head_t	open_wait;	/* Open waiters */
231	wait_queue_head_t	close_wait;	/* Close waiters */
232	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
233	unsigned long		flags;		/* TTY flags ASY_*/
234	unsigned char		console:1;	/* port is a console */
235	struct mutex		mutex;		/* Locking */
236	struct mutex		buf_mutex;	/* Buffer alloc lock */
237	unsigned char		*xmit_buf;	/* Optional buffer */
238	unsigned int		close_delay;	/* Close port delay */
239	unsigned int		closing_wait;	/* Delay for output */
240	int			drain_delay;	/* Set to zero if no pure time
241						   based drain is needed else
242						   set to size of fifo */
243	struct kref		kref;		/* Ref counter */
244};
245
246/*
247 * Where all of the state associated with a tty is kept while the tty
248 * is open.  Since the termios state should be kept even if the tty
249 * has been closed --- for things like the baud rate, etc --- it is
250 * not stored here, but rather a pointer to the real state is stored
251 * here.  Possible the winsize structure should have the same
252 * treatment, but (1) the default 80x24 is usually right and (2) it's
253 * most often used by a windowing system, which will set the correct
254 * size each time the window is created or resized anyway.
255 * 						- TYT, 9/14/92
256 */
257
258struct tty_operations;
259
260struct tty_struct {
261	int	magic;
262	struct kref kref;
263	struct device *dev;
264	struct tty_driver *driver;
265	const struct tty_operations *ops;
266	int index;
267
268	/* Protects ldisc changes: Lock tty not pty */
269	struct mutex ldisc_mutex;
270	struct tty_ldisc *ldisc;
271
272	struct mutex legacy_mutex;
273	struct mutex termios_mutex;
274	spinlock_t ctrl_lock;
275	/* Termios values are protected by the termios mutex */
276	struct ktermios termios, termios_locked;
277	struct termiox *termiox;	/* May be NULL for unsupported */
278	char name[64];
279	struct pid *pgrp;		/* Protected by ctrl lock */
280	struct pid *session;
281	unsigned long flags;
282	int count;
283	struct winsize winsize;		/* termios mutex */
284	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
285	unsigned char low_latency:1, warned:1;
286	unsigned char ctrl_status;	/* ctrl_lock */
287	unsigned int receive_room;	/* Bytes free for queue */
288
289	struct tty_struct *link;
290	struct fasync_struct *fasync;
291	struct tty_bufhead buf;		/* Locked internally */
292	int alt_speed;		/* For magic substitution of 38400 bps */
293	wait_queue_head_t write_wait;
294	wait_queue_head_t read_wait;
295	struct work_struct hangup_work;
296	void *disc_data;
297	void *driver_data;
298	struct list_head tty_files;
299
300#define N_TTY_BUF_SIZE 4096
301
302	/*
303	 * The following is data for the N_TTY line discipline.  For
304	 * historical reasons, this is included in the tty structure.
305	 * Mostly locked by the BKL.
306	 */
307	unsigned int column;
308	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
309	unsigned char closing:1;
310	unsigned char echo_overrun:1;
311	unsigned short minimum_to_wake;
312	unsigned long overrun_time;
313	int num_overrun;
314	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
315	char *read_buf;
316	int read_head;
317	int read_tail;
318	int read_cnt;
319	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
320	unsigned char *echo_buf;
321	unsigned int echo_pos;
322	unsigned int echo_cnt;
323	int canon_data;
324	unsigned long canon_head;
325	unsigned int canon_column;
326	struct mutex atomic_read_lock;
327	struct mutex atomic_write_lock;
328	struct mutex output_lock;
329	struct mutex echo_lock;
330	unsigned char *write_buf;
331	int write_cnt;
332	spinlock_t read_lock;
333	/* If the tty has a pending do_SAK, queue it here - akpm */
334	struct work_struct SAK_work;
335	struct tty_port *port;
336};
337
338/* Each of a tty's open files has private_data pointing to tty_file_private */
339struct tty_file_private {
340	struct tty_struct *tty;
341	struct file *file;
342	struct list_head list;
343};
344
345/* tty magic number */
346#define TTY_MAGIC		0x5401
347
348/*
349 * These bits are used in the flags field of the tty structure.
350 *
351 * So that interrupts won't be able to mess up the queues,
352 * copy_to_cooked must be atomic with respect to itself, as must
353 * tty->write.  Thus, you must use the inline functions set_bit() and
354 * clear_bit() to make things atomic.
355 */
356#define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
357#define TTY_IO_ERROR 		1	/* Cause an I/O error (may be no ldisc too) */
358#define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
359#define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
360#define TTY_DEBUG 		4	/* Debugging */
361#define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
362#define TTY_PUSH 		6	/* n_tty private */
363#define TTY_CLOSING 		7	/* ->close() in progress */
364#define TTY_LDISC 		9	/* Line discipline attached */
365#define TTY_LDISC_CHANGING 	10	/* Line discipline changing */
366#define TTY_LDISC_OPEN	 	11	/* Line discipline is open */
367#define TTY_HW_COOK_OUT 	14	/* Hardware can do output cooking */
368#define TTY_HW_COOK_IN 		15	/* Hardware can do input cooking */
369#define TTY_PTY_LOCK 		16	/* pty private */
370#define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
371#define TTY_HUPPED 		18	/* Post driver->hangup() */
372#define TTY_FLUSHING		19	/* Flushing to ldisc in progress */
373#define TTY_FLUSHPENDING	20	/* Queued buffer flush pending */
374#define TTY_HUPPING 		21	/* ->hangup() in progress */
375
376#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
377
378extern void tty_write_flush(struct tty_struct *);
379
380extern struct ktermios tty_std_termios;
381
382extern void console_init(void);
383extern int vcs_init(void);
384
385extern struct class *tty_class;
386
387/**
388 *	tty_kref_get		-	get a tty reference
389 *	@tty: tty device
390 *
391 *	Return a new reference to a tty object. The caller must hold
392 *	sufficient locks/counts to ensure that their existing reference cannot
393 *	go away
394 */
395
396static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
397{
398	if (tty)
399		kref_get(&tty->kref);
400	return tty;
401}
402extern void tty_kref_put(struct tty_struct *tty);
403
404extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
405			      const char *routine);
406extern char *tty_name(struct tty_struct *tty, char *buf);
407extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
408extern int tty_check_change(struct tty_struct *tty);
409extern void stop_tty(struct tty_struct *tty);
410extern void start_tty(struct tty_struct *tty);
411extern int tty_register_driver(struct tty_driver *driver);
412extern int tty_unregister_driver(struct tty_driver *driver);
413extern struct device *tty_register_device(struct tty_driver *driver,
414					  unsigned index, struct device *dev);
415extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
416extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
417			     int buflen);
418extern void tty_write_message(struct tty_struct *tty, char *msg);
419extern int tty_put_char(struct tty_struct *tty, unsigned char c);
420extern int tty_chars_in_buffer(struct tty_struct *tty);
421extern int tty_write_room(struct tty_struct *tty);
422extern void tty_driver_flush_buffer(struct tty_struct *tty);
423extern void tty_throttle(struct tty_struct *tty);
424extern void tty_unthrottle(struct tty_struct *tty);
425extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
426extern void tty_driver_remove_tty(struct tty_driver *driver,
427				  struct tty_struct *tty);
428extern void tty_free_termios(struct tty_struct *tty);
429extern int is_current_pgrp_orphaned(void);
430extern struct pid *tty_get_pgrp(struct tty_struct *tty);
431extern int is_ignored(int sig);
432extern int tty_signal(int sig, struct tty_struct *tty);
433extern void tty_hangup(struct tty_struct *tty);
434extern void tty_vhangup(struct tty_struct *tty);
435extern void tty_vhangup_locked(struct tty_struct *tty);
436extern void tty_vhangup_self(void);
437extern void tty_unhangup(struct file *filp);
438extern int tty_hung_up_p(struct file *filp);
439extern void do_SAK(struct tty_struct *tty);
440extern void __do_SAK(struct tty_struct *tty);
441extern void disassociate_ctty(int priv);
442extern void no_tty(void);
443extern void tty_flip_buffer_push(struct tty_struct *tty);
444extern void tty_flush_to_ldisc(struct tty_struct *tty);
445extern void tty_buffer_free_all(struct tty_struct *tty);
446extern void tty_buffer_flush(struct tty_struct *tty);
447extern void tty_buffer_init(struct tty_struct *tty);
448extern speed_t tty_get_baud_rate(struct tty_struct *tty);
449extern speed_t tty_termios_baud_rate(struct ktermios *termios);
450extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
451extern void tty_termios_encode_baud_rate(struct ktermios *termios,
452						speed_t ibaud, speed_t obaud);
453extern void tty_encode_baud_rate(struct tty_struct *tty,
454						speed_t ibaud, speed_t obaud);
455extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
456extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
457extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
458
459extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
460extern void tty_ldisc_deref(struct tty_ldisc *);
461extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
462extern void tty_ldisc_hangup(struct tty_struct *tty);
463extern const struct file_operations tty_ldiscs_proc_fops;
464
465extern void tty_wakeup(struct tty_struct *tty);
466extern void tty_ldisc_flush(struct tty_struct *tty);
467
468extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
469extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
470			unsigned int cmd, unsigned long arg);
471extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
472extern dev_t tty_devnum(struct tty_struct *tty);
473extern void proc_clear_tty(struct task_struct *p);
474extern struct tty_struct *get_current_tty(void);
475extern void tty_default_fops(struct file_operations *fops);
476extern struct tty_struct *alloc_tty_struct(void);
477extern int tty_alloc_file(struct file *file);
478extern void tty_add_file(struct tty_struct *tty, struct file *file);
479extern void tty_free_file(struct file *file);
480extern void free_tty_struct(struct tty_struct *tty);
481extern void initialize_tty_struct(struct tty_struct *tty,
482		struct tty_driver *driver, int idx);
483extern void deinitialize_tty_struct(struct tty_struct *tty);
484extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
485extern int tty_release(struct inode *inode, struct file *filp);
486extern int tty_init_termios(struct tty_struct *tty);
487extern int tty_standard_install(struct tty_driver *driver,
488		struct tty_struct *tty);
489
490extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
491extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
492
493extern struct mutex tty_mutex;
494extern spinlock_t tty_files_lock;
495
496extern void tty_write_unlock(struct tty_struct *tty);
497extern int tty_write_lock(struct tty_struct *tty, int ndelay);
498#define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
499
500extern void tty_port_init(struct tty_port *port);
501extern void tty_port_link_device(struct tty_port *port,
502		struct tty_driver *driver, unsigned index);
503extern struct device *tty_port_register_device(struct tty_port *port,
504		struct tty_driver *driver, unsigned index,
505		struct device *device);
506extern int tty_port_alloc_xmit_buf(struct tty_port *port);
507extern void tty_port_free_xmit_buf(struct tty_port *port);
508extern void tty_port_put(struct tty_port *port);
509
510static inline struct tty_port *tty_port_get(struct tty_port *port)
511{
512	if (port)
513		kref_get(&port->kref);
514	return port;
515}
516
517/* If the cts flow control is enabled, return true. */
518static inline bool tty_port_cts_enabled(struct tty_port *port)
519{
520	return port->flags & ASYNC_CTS_FLOW;
521}
522
523extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
524extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
525extern int tty_port_carrier_raised(struct tty_port *port);
526extern void tty_port_raise_dtr_rts(struct tty_port *port);
527extern void tty_port_lower_dtr_rts(struct tty_port *port);
528extern void tty_port_hangup(struct tty_port *port);
529extern int tty_port_block_til_ready(struct tty_port *port,
530				struct tty_struct *tty, struct file *filp);
531extern int tty_port_close_start(struct tty_port *port,
532				struct tty_struct *tty, struct file *filp);
533extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
534extern void tty_port_close(struct tty_port *port,
535				struct tty_struct *tty, struct file *filp);
536extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
537				struct tty_struct *tty);
538extern int tty_port_open(struct tty_port *port,
539				struct tty_struct *tty, struct file *filp);
540static inline int tty_port_users(struct tty_port *port)
541{
542	return port->count + port->blocked_open;
543}
544
545extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
546extern int tty_unregister_ldisc(int disc);
547extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
548extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
549extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
550extern void tty_ldisc_init(struct tty_struct *tty);
551extern void tty_ldisc_deinit(struct tty_struct *tty);
552extern void tty_ldisc_begin(void);
553/* This last one is just for the tty layer internals and shouldn't be used elsewhere */
554extern void tty_ldisc_enable(struct tty_struct *tty);
555
556
557/* n_tty.c */
558extern struct tty_ldisc_ops tty_ldisc_N_TTY;
559extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
560
561/* tty_audit.c */
562#ifdef CONFIG_AUDIT
563extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
564			       size_t size);
565extern void tty_audit_exit(void);
566extern void tty_audit_fork(struct signal_struct *sig);
567extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
568extern void tty_audit_push(struct tty_struct *tty);
569extern int tty_audit_push_task(struct task_struct *tsk,
570			       uid_t loginuid, u32 sessionid);
571#else
572static inline void tty_audit_add_data(struct tty_struct *tty,
573				      unsigned char *data, size_t size)
574{
575}
576static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
577{
578}
579static inline void tty_audit_exit(void)
580{
581}
582static inline void tty_audit_fork(struct signal_struct *sig)
583{
584}
585static inline void tty_audit_push(struct tty_struct *tty)
586{
587}
588static inline int tty_audit_push_task(struct task_struct *tsk,
589				      uid_t loginuid, u32 sessionid)
590{
591	return 0;
592}
593#endif
594
595/* tty_io.c */
596extern int __init tty_init(void);
597
598/* tty_ioctl.c */
599extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
600		       unsigned int cmd, unsigned long arg);
601extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
602		       unsigned int cmd, unsigned long arg);
603
604/* serial.c */
605
606extern void serial_console_init(void);
607
608/* pcxx.c */
609
610extern int pcxe_open(struct tty_struct *tty, struct file *filp);
611
612/* vt.c */
613
614extern int vt_ioctl(struct tty_struct *tty,
615		    unsigned int cmd, unsigned long arg);
616
617extern long vt_compat_ioctl(struct tty_struct *tty,
618		     unsigned int cmd, unsigned long arg);
619
620/* tty_mutex.c */
621/* functions for preparation of BKL removal */
622extern void __lockfunc tty_lock(struct tty_struct *tty);
623extern void __lockfunc tty_unlock(struct tty_struct *tty);
624extern void __lockfunc tty_lock_pair(struct tty_struct *tty,
625				struct tty_struct *tty2);
626extern void __lockfunc tty_unlock_pair(struct tty_struct *tty,
627				struct tty_struct *tty2);
628
629/*
630 * this shall be called only from where BTM is held (like close)
631 *
632 * We need this to ensure nobody waits for us to finish while we are waiting.
633 * Without this we were encountering system stalls.
634 *
635 * This should be indeed removed with BTM removal later.
636 *
637 * Locking: BTM required. Nobody is allowed to hold port->mutex.
638 */
639static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
640		long timeout)
641{
642	tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */
643	tty_wait_until_sent(tty, timeout);
644	tty_lock(tty);
645}
646
647/*
648 * wait_event_interruptible_tty -- wait for a condition with the tty lock held
649 *
650 * The condition we are waiting for might take a long time to
651 * become true, or might depend on another thread taking the
652 * BTM. In either case, we need to drop the BTM to guarantee
653 * forward progress. This is a leftover from the conversion
654 * from the BKL and should eventually get removed as the BTM
655 * falls out of use.
656 *
657 * Do not use in new code.
658 */
659#define wait_event_interruptible_tty(tty, wq, condition)		\
660({									\
661	int __ret = 0;							\
662	if (!(condition)) {						\
663		__wait_event_interruptible_tty(tty, wq, condition, __ret);	\
664	}								\
665	__ret;								\
666})
667
668#define __wait_event_interruptible_tty(tty, wq, condition, ret)		\
669do {									\
670	DEFINE_WAIT(__wait);						\
671									\
672	for (;;) {							\
673		prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);	\
674		if (condition)						\
675			break;						\
676		if (!signal_pending(current)) {				\
677			tty_unlock(tty);					\
678			schedule();					\
679			tty_lock(tty);					\
680			continue;					\
681		}							\
682		ret = -ERESTARTSYS;					\
683		break;							\
684	}								\
685	finish_wait(&wq, &__wait);					\
686} while (0)
687
688
689#endif /* __KERNEL__ */
690#endif
691