File: /usr/src/linux/net/irda/ircomm/ircomm_tty.c
1 /*********************************************************************
2 *
3 * Filename: ircomm_tty.c
4 * Version: 1.0
5 * Description: IrCOMM serial TTY driver
6 * Status: Experimental.
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Sun Jun 6 21:00:56 1999
9 * Modified at: Wed Feb 23 00:09:02 2000
10 * Modified by: Dag Brattli <dagb@cs.uit.no>
11 * Sources: serial.c and previous IrCOMM work by Takahide Higuchi
12 *
13 * Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation; either version 2 of
18 * the License, or (at your option) any later version.
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
28 * MA 02111-1307 USA
29 *
30 ********************************************************************/
31
32 #include <linux/config.h>
33 #include <linux/init.h>
34 #include <linux/module.h>
35 #include <linux/fs.h>
36 #include <linux/sched.h>
37 #include <linux/termios.h>
38 #include <linux/tty.h>
39 #include <linux/interrupt.h>
40
41 #include <asm/segment.h>
42 #include <asm/uaccess.h>
43
44 #include <net/irda/irda.h>
45 #include <net/irda/irmod.h>
46
47 #include <net/irda/ircomm_core.h>
48 #include <net/irda/ircomm_param.h>
49 #include <net/irda/ircomm_tty_attach.h>
50 #include <net/irda/ircomm_tty.h>
51
52 static int ircomm_tty_open(struct tty_struct *tty, struct file *filp);
53 static void ircomm_tty_close(struct tty_struct * tty, struct file *filp);
54 static int ircomm_tty_write(struct tty_struct * tty, int from_user,
55 const unsigned char *buf, int count);
56 static int ircomm_tty_write_room(struct tty_struct *tty);
57 static void ircomm_tty_throttle(struct tty_struct *tty);
58 static void ircomm_tty_unthrottle(struct tty_struct *tty);
59 static int ircomm_tty_chars_in_buffer(struct tty_struct *tty);
60 static void ircomm_tty_flush_buffer(struct tty_struct *tty);
61 static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch);
62 static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout);
63 static void ircomm_tty_hangup(struct tty_struct *tty);
64 static void ircomm_tty_do_softint(void *private_);
65 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self);
66
67 static int ircomm_tty_data_indication(void *instance, void *sap,
68 struct sk_buff *skb);
69 static int ircomm_tty_control_indication(void *instance, void *sap,
70 struct sk_buff *skb);
71 static void ircomm_tty_flow_indication(void *instance, void *sap,
72 LOCAL_FLOW cmd);
73 #ifdef CONFIG_PROC_FS
74 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
75 int *eof, void *unused);
76 #endif /* CONFIG_PROC_FS */
77 static struct tty_driver driver;
78 static int ircomm_tty_refcount; /* If we manage several devices */
79
80 static struct tty_struct *ircomm_tty_table[NR_PTYS];
81 static struct termios *ircomm_tty_termios[NR_PTYS];
82 static struct termios *ircomm_tty_termios_locked[NR_PTYS];
83
84 hashbin_t *ircomm_tty = NULL;
85
86 /*
87 * Function ircomm_tty_init()
88 *
89 * Init IrCOMM TTY layer/driver
90 *
91 */
92 int __init ircomm_tty_init(void)
93 {
94 ircomm_tty = hashbin_new(HB_LOCAL);
95 if (ircomm_tty == NULL) {
96 ERROR(__FUNCTION__ "(), can't allocate hashbin!\n");
97 return -ENOMEM;
98 }
99
100 memset(&driver, 0, sizeof(struct tty_driver));
101 driver.magic = TTY_DRIVER_MAGIC;
102 driver.driver_name = "ircomm";
103 #ifdef CONFIG_DEVFS_FS
104 driver.name = "ircomm%d";
105 #else
106 driver.name = "ircomm";
107 #endif
108 driver.major = IRCOMM_TTY_MAJOR;
109 driver.minor_start = IRCOMM_TTY_MINOR;
110 driver.num = IRCOMM_TTY_PORTS;
111 driver.type = TTY_DRIVER_TYPE_SERIAL;
112 driver.subtype = SERIAL_TYPE_NORMAL;
113 driver.init_termios = tty_std_termios;
114 driver.init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
115 driver.flags = TTY_DRIVER_REAL_RAW;
116 driver.refcount = &ircomm_tty_refcount;
117 driver.table = ircomm_tty_table;
118 driver.termios = ircomm_tty_termios;
119 driver.termios_locked = ircomm_tty_termios_locked;
120 driver.open = ircomm_tty_open;
121 driver.close = ircomm_tty_close;
122 driver.write = ircomm_tty_write;
123 driver.write_room = ircomm_tty_write_room;
124 driver.chars_in_buffer = ircomm_tty_chars_in_buffer;
125 driver.flush_buffer = ircomm_tty_flush_buffer;
126 driver.ioctl = ircomm_tty_ioctl;
127 driver.throttle = ircomm_tty_throttle;
128 driver.unthrottle = ircomm_tty_unthrottle;
129 driver.send_xchar = ircomm_tty_send_xchar;
130 driver.set_termios = ircomm_tty_set_termios;
131 driver.stop = ircomm_tty_stop;
132 driver.start = ircomm_tty_start;
133 driver.hangup = ircomm_tty_hangup;
134 driver.wait_until_sent = ircomm_tty_wait_until_sent;
135 #ifdef CONFIG_PROC_FS
136 driver.read_proc = ircomm_tty_read_proc;
137 #endif /* CONFIG_PROC_FS */
138 if (tty_register_driver(&driver)) {
139 ERROR(__FUNCTION__ "Couldn't register serial driver\n");
140 return -1;
141 }
142 return 0;
143 }
144
145 #ifdef MODULE
146 static void __ircomm_tty_cleanup(struct ircomm_tty_cb *self)
147 {
148 IRDA_DEBUG(0, __FUNCTION__ "()\n");
149
150 ASSERT(self != NULL, return;);
151 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
152
153 ircomm_tty_shutdown(self);
154
155 self->magic = 0;
156 kfree(self);
157 }
158
159 /*
160 * Function ircomm_tty_cleanup ()
161 *
162 * Remove IrCOMM TTY layer/driver
163 *
164 */
165 void ircomm_tty_cleanup(void)
166 {
167 int ret;
168
169 IRDA_DEBUG(4, __FUNCTION__"()\n");
170
171 ret = tty_unregister_driver(&driver);
172 if (ret) {
173 ERROR(__FUNCTION__ "(), failed to unregister driver\n");
174 return;
175 }
176
177 hashbin_delete(ircomm_tty, (FREE_FUNC) __ircomm_tty_cleanup);
178 }
179 #endif /* MODULE */
180
181 /*
182 * Function ircomm_startup (self)
183 *
184 *
185 *
186 */
187 static int ircomm_tty_startup(struct ircomm_tty_cb *self)
188 {
189 notify_t notify;
190 int ret;
191
192 IRDA_DEBUG(2, __FUNCTION__ "()\n");
193
194 ASSERT(self != NULL, return -1;);
195 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
196
197 /* Already open */
198 if (self->flags & ASYNC_INITIALIZED) {
199 IRDA_DEBUG(2, __FUNCTION__ "(), already open so break out!\n");
200 return 0;
201 }
202
203 /* Register with IrCOMM */
204 irda_notify_init(¬ify);
205 /* These callbacks we must handle ourselves */
206 notify.data_indication = ircomm_tty_data_indication;
207 notify.udata_indication = ircomm_tty_control_indication;
208 notify.flow_indication = ircomm_tty_flow_indication;
209
210 /* Use the ircomm_tty interface for these ones */
211 notify.disconnect_indication = ircomm_tty_disconnect_indication;
212 notify.connect_confirm = ircomm_tty_connect_confirm;
213 notify.connect_indication = ircomm_tty_connect_indication;
214 strncpy(notify.name, "ircomm_tty", NOTIFY_MAX_NAME);
215 notify.instance = self;
216
217 if (!self->ircomm) {
218 self->ircomm = ircomm_open(¬ify, self->service_type,
219 self->line);
220 }
221 if (!self->ircomm)
222 return -ENODEV;
223
224 self->slsap_sel = self->ircomm->slsap_sel;
225
226 /* Connect IrCOMM link with remote device */
227 ret = ircomm_tty_attach_cable(self);
228 if (ret < 0) {
229 ERROR(__FUNCTION__ "(), error attaching cable!\n");
230 return ret;
231 }
232
233 self->flags |= ASYNC_INITIALIZED;
234
235 return 0;
236 }
237
238 /*
239 * Function ircomm_block_til_ready (self, filp)
240 *
241 *
242 *
243 */
244 static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
245 struct file *filp)
246 {
247 DECLARE_WAITQUEUE(wait, current);
248 int retval;
249 int do_clocal = 0, extra_count = 0;
250 unsigned long flags;
251 struct tty_struct *tty;
252
253 IRDA_DEBUG(2, __FUNCTION__ "()\n");
254
255 tty = self->tty;
256
257 if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
258 /* this is a callout device */
259 /* just verify that normal device is not in use */
260 if (self->flags & ASYNC_NORMAL_ACTIVE)
261 return -EBUSY;
262 if ((self->flags & ASYNC_CALLOUT_ACTIVE) &&
263 (self->flags & ASYNC_SESSION_LOCKOUT) &&
264 (self->session != current->session))
265 return -EBUSY;
266 if ((self->flags & ASYNC_CALLOUT_ACTIVE) &&
267 (self->flags & ASYNC_PGRP_LOCKOUT) &&
268 (self->pgrp != current->pgrp))
269 return -EBUSY;
270 self->flags |= ASYNC_CALLOUT_ACTIVE;
271 return 0;
272 }
273
274 /*
275 * If non-blocking mode is set, or the port is not enabled,
276 * then make the check up front and then exit.
277 */
278 if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
279 /* nonblock mode is set or port is not enabled */
280 /* just verify that callout device is not active */
281 if (self->flags & ASYNC_CALLOUT_ACTIVE)
282 return -EBUSY;
283 self->flags |= ASYNC_NORMAL_ACTIVE;
284
285 IRDA_DEBUG(1, __FUNCTION__ "(), O_NONBLOCK requested!\n");
286 return 0;
287 }
288
289 if (self->flags & ASYNC_CALLOUT_ACTIVE) {
290 if (self->normal_termios.c_cflag & CLOCAL) {
291 IRDA_DEBUG(1, __FUNCTION__ "(), doing CLOCAL!\n");
292 do_clocal = 1;
293 }
294 } else {
295 if (tty->termios->c_cflag & CLOCAL) {
296 IRDA_DEBUG(1, __FUNCTION__ "(), doing CLOCAL!\n");
297 do_clocal = 1;
298 }
299 }
300
301 /* Wait for carrier detect and the line to become
302 * free (i.e., not in use by the callout). While we are in
303 * this loop, self->open_count is dropped by one, so that
304 * mgsl_close() knows when to free things. We restore it upon
305 * exit, either normal or abnormal.
306 */
307
308 retval = 0;
309 add_wait_queue(&self->open_wait, &wait);
310
311 IRDA_DEBUG(2, "%s(%d):block_til_ready before block on %s open_count=%d\n",
312 __FILE__,__LINE__, tty->driver.name, self->open_count );
313
314 save_flags(flags); cli();
315 if (!tty_hung_up_p(filp)) {
316 extra_count = 1;
317 self->open_count--;
318 }
319 restore_flags(flags);
320 self->blocked_open++;
321
322 while (1) {
323 if (!(self->flags & ASYNC_CALLOUT_ACTIVE) &&
324 (tty->termios->c_cflag & CBAUD)) {
325 save_flags(flags); cli();
326 self->settings.dte |= IRCOMM_RTS + IRCOMM_DTR;
327
328 ircomm_param_request(self, IRCOMM_DTE, TRUE);
329 restore_flags(flags);
330 }
331
332 current->state = TASK_INTERRUPTIBLE;
333
334 if (tty_hung_up_p(filp) || !(self->flags & ASYNC_INITIALIZED)){
335 retval = (self->flags & ASYNC_HUP_NOTIFY) ?
336 -EAGAIN : -ERESTARTSYS;
337 break;
338 }
339
340 /*
341 * Check if link is ready now. Even if CLOCAL is
342 * specified, we cannot return before the IrCOMM link is
343 * ready
344 */
345 if (!(self->flags & ASYNC_CALLOUT_ACTIVE) &&
346 !(self->flags & ASYNC_CLOSING) &&
347 (do_clocal || (self->settings.dce & IRCOMM_CD)) &&
348 self->state == IRCOMM_TTY_READY)
349 {
350 break;
351 }
352
353 if (signal_pending(current)) {
354 retval = -ERESTARTSYS;
355 break;
356 }
357
358 IRDA_DEBUG(1, "%s(%d):block_til_ready blocking on %s open_count=%d\n",
359 __FILE__,__LINE__, tty->driver.name, self->open_count );
360
361 schedule();
362 }
363
364 __set_current_state(TASK_RUNNING);
365 remove_wait_queue(&self->open_wait, &wait);
366
367 if (extra_count)
368 self->open_count++;
369 self->blocked_open--;
370
371 IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n",
372 __FILE__,__LINE__, tty->driver.name, self->open_count);
373
374 if (!retval)
375 self->flags |= ASYNC_NORMAL_ACTIVE;
376
377 return retval;
378 }
379
380 /*
381 * Function ircomm_tty_open (tty, filp)
382 *
383 * This routine is called when a particular tty device is opened. This
384 * routine is mandatory; if this routine is not filled in, the attempted
385 * open will fail with ENODEV.
386 */
387 static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
388 {
389 struct ircomm_tty_cb *self;
390 int line;
391 int ret;
392
393 IRDA_DEBUG(2, __FUNCTION__ "()\n");
394
395 MOD_INC_USE_COUNT;
396 line = MINOR(tty->device) - tty->driver.minor_start;
397 if ((line < 0) || (line >= IRCOMM_TTY_PORTS)) {
398 MOD_DEC_USE_COUNT;
399 return -ENODEV;
400 }
401
402 /* Check if instance already exists */
403 self = hashbin_find(ircomm_tty, line, NULL);
404 if (!self) {
405 /* No, so make new instance */
406 self = kmalloc(sizeof(struct ircomm_tty_cb), GFP_KERNEL);
407 if (self == NULL) {
408 ERROR(__FUNCTION__"(), kmalloc failed!\n");
409 MOD_DEC_USE_COUNT;
410 return -ENOMEM;
411 }
412 memset(self, 0, sizeof(struct ircomm_tty_cb));
413
414 self->magic = IRCOMM_TTY_MAGIC;
415 self->flow = FLOW_STOP;
416
417 self->line = line;
418 self->tqueue.routine = ircomm_tty_do_softint;
419 self->tqueue.data = self;
420 self->max_header_size = 5;
421 self->max_data_size = 64-self->max_header_size;
422 self->close_delay = 5*HZ/10;
423 self->closing_wait = 30*HZ;
424
425 /* Init some important stuff */
426 init_timer(&self->watchdog_timer);
427 init_waitqueue_head(&self->open_wait);
428 init_waitqueue_head(&self->close_wait);
429
430 /*
431 * Force TTY into raw mode by default which is usually what
432 * we want for IrCOMM and IrLPT. This way applications will
433 * not have to twiddle with printcap etc.
434 */
435 tty->termios->c_iflag = 0;
436 tty->termios->c_oflag = 0;
437
438 /* Insert into hash */
439 hashbin_insert(ircomm_tty, (irda_queue_t *) self, line, NULL);
440 }
441 self->open_count++;
442
443 tty->driver_data = self;
444 self->tty = tty;
445
446 IRDA_DEBUG(1, __FUNCTION__"(), %s%d, count = %d\n", tty->driver.name,
447 self->line, self->open_count);
448
449 /* Not really used by us, but lets do it anyway */
450 self->tty->low_latency = (self->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
451
452 /*
453 * If the port is the middle of closing, bail out now
454 */
455 if (tty_hung_up_p(filp) ||
456 (self->flags & ASYNC_CLOSING)) {
457 if (self->flags & ASYNC_CLOSING)
458 interruptible_sleep_on(&self->close_wait);
459 /* MOD_DEC_USE_COUNT; "info->tty" will cause this? */
460 #ifdef SERIAL_DO_RESTART
461 return ((self->flags & ASYNC_HUP_NOTIFY) ?
462 -EAGAIN : -ERESTARTSYS);
463 #else
464 return -EAGAIN;
465 #endif
466 }
467
468 /* Check if this is a "normal" ircomm device, or an irlpt device */
469 if (line < 0x10) {
470 self->service_type = IRCOMM_3_WIRE | IRCOMM_9_WIRE;
471 self->settings.service_type = IRCOMM_9_WIRE; /* 9 wire as default */
472 self->settings.dce = IRCOMM_CTS | IRCOMM_CD; /* Default line settings */
473 IRDA_DEBUG(2, __FUNCTION__ "(), IrCOMM device\n");
474 } else {
475 IRDA_DEBUG(2, __FUNCTION__ "(), IrLPT device\n");
476 self->service_type = IRCOMM_3_WIRE_RAW;
477 self->settings.service_type = IRCOMM_3_WIRE_RAW; /* Default */
478 }
479
480 ret = ircomm_tty_startup(self);
481 if (ret)
482 return ret;
483
484 ret = ircomm_tty_block_til_ready(self, filp);
485 if (ret) {
486 /* MOD_DEC_USE_COUNT; "info->tty" will cause this? */
487 IRDA_DEBUG(2, __FUNCTION__
488 "(), returning after block_til_ready with %d\n",
489 ret);
490
491 return ret;
492 }
493
494 self->session = current->session;
495 self->pgrp = current->pgrp;
496
497 return 0;
498 }
499
500 /*
501 * Function ircomm_tty_close (tty, filp)
502 *
503 * This routine is called when a particular tty device is closed.
504 *
505 */
506 static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
507 {
508 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
509 unsigned long flags;
510
511 IRDA_DEBUG(0, __FUNCTION__ "()\n");
512
513 if (!tty)
514 return;
515
516 save_flags(flags);
517 cli();
518
519 if (tty_hung_up_p(filp)) {
520 MOD_DEC_USE_COUNT;
521 restore_flags(flags);
522
523 IRDA_DEBUG(0, __FUNCTION__ "(), returning 1\n");
524 return;
525 }
526
527 ASSERT(self != NULL, return;);
528 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
529
530 if ((tty->count == 1) && (self->open_count != 1)) {
531 /*
532 * Uh, oh. tty->count is 1, which means that the tty
533 * structure will be freed. state->count should always
534 * be one in these conditions. If it's greater than
535 * one, we've got real problems, since it means the
536 * serial port won't be shutdown.
537 */
538 IRDA_DEBUG(0, __FUNCTION__ "(), bad serial port count; "
539 "tty->count is 1, state->count is %d\n",
540 self->open_count);
541 self->open_count = 1;
542 }
543
544 if (--self->open_count < 0) {
545 ERROR(__FUNCTION__
546 "(), bad serial port count for ttys%d: %d\n",
547 self->line, self->open_count);
548 self->open_count = 0;
549 }
550 if (self->open_count) {
551 MOD_DEC_USE_COUNT;
552 restore_flags(flags);
553
554 IRDA_DEBUG(0, __FUNCTION__ "(), open count > 0\n");
555 return;
556 }
557 self->flags |= ASYNC_CLOSING;
558
559 /*
560 * Now we wait for the transmit buffer to clear; and we notify
561 * the line discipline to only process XON/XOFF characters.
562 */
563 tty->closing = 1;
564 if (self->closing_wait != ASYNC_CLOSING_WAIT_NONE)
565 tty_wait_until_sent(tty, self->closing_wait);
566
567 ircomm_tty_shutdown(self);
568
569 if (tty->driver.flush_buffer)
570 tty->driver.flush_buffer(tty);
571 if (tty->ldisc.flush_buffer)
572 tty->ldisc.flush_buffer(tty);
573
574 tty->closing = 0;
575 self->tty = 0;
576
577 if (self->blocked_open) {
578 if (self->close_delay) {
579 current->state = TASK_INTERRUPTIBLE;
580 schedule_timeout(self->close_delay);
581 }
582 wake_up_interruptible(&self->open_wait);
583 }
584
585 self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
586 ASYNC_CLOSING);
587 wake_up_interruptible(&self->close_wait);
588
589 MOD_DEC_USE_COUNT;
590 restore_flags(flags);
591 }
592
593 /*
594 * Function ircomm_tty_flush_buffer (tty)
595 *
596 *
597 *
598 */
599 static void ircomm_tty_flush_buffer(struct tty_struct *tty)
600 {
601 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
602
603 ASSERT(self != NULL, return;);
604 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
605
606 /*
607 * Let do_softint() do this to avoid race condition with
608 * do_softint() ;-)
609 */
610 queue_task(&self->tqueue, &tq_immediate);
611 mark_bh(IMMEDIATE_BH);
612 }
613
614 /*
615 * Function ircomm_tty_do_softint (private_)
616 *
617 * We use this routine to give the write wakeup to the user at at a
618 * safe time (as fast as possible after write have completed). This
619 * can be compared to the Tx interrupt.
620 */
621 static void ircomm_tty_do_softint(void *private_)
622 {
623 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) private_;
624 struct tty_struct *tty;
625 unsigned long flags;
626 struct sk_buff *skb, *ctrl_skb;
627
628 IRDA_DEBUG(2, __FUNCTION__ "()\n");
629
630 if (!self || self->magic != IRCOMM_TTY_MAGIC)
631 return;
632
633 tty = self->tty;
634 if (!tty)
635 return;
636
637 /* Unlink control buffer */
638 save_flags(flags);
639 cli();
640
641 ctrl_skb = self->ctrl_skb;
642 self->ctrl_skb = NULL;
643
644 restore_flags(flags);
645
646 /* Flush control buffer if any */
647 if (ctrl_skb && self->flow == FLOW_START)
648 ircomm_control_request(self->ircomm, ctrl_skb);
649
650 if (tty->hw_stopped)
651 return;
652
653 /* Unlink transmit buffer */
654 save_flags(flags);
655 cli();
656
657 skb = self->tx_skb;
658 self->tx_skb = NULL;
659
660 restore_flags(flags);
661
662 /* Flush transmit buffer if any */
663 if (skb)
664 ircomm_tty_do_event(self, IRCOMM_TTY_DATA_REQUEST, skb, NULL);
665
666 /* Check if user (still) wants to be waken up */
667 if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
668 tty->ldisc.write_wakeup)
669 {
670 (tty->ldisc.write_wakeup)(tty);
671 }
672 wake_up_interruptible(&tty->write_wait);
673 }
674
675 /*
676 * Function ircomm_tty_write (tty, from_user, buf, count)
677 *
678 * This routine is called by the kernel to write a series of characters
679 * to the tty device. The characters may come from user space or kernel
680 * space. This routine will return the number of characters actually
681 * accepted for writing. This routine is mandatory.
682 */
683 static int ircomm_tty_write(struct tty_struct *tty, int from_user,
684 const unsigned char *buf, int count)
685 {
686 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
687 unsigned long flags;
688 struct sk_buff *skb;
689 int tailroom = 0;
690 int len = 0;
691 int size;
692
693 IRDA_DEBUG(2, __FUNCTION__ "(), count=%d, hw_stopped=%d\n", count,
694 tty->hw_stopped);
695
696 ASSERT(self != NULL, return -1;);
697 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
698
699 save_flags(flags);
700 cli();
701
702 /* Fetch current transmit buffer */
703 skb = self->tx_skb;
704
705 /*
706 * Send out all the data we get, possibly as multiple fragmented
707 * frames, but this will only happen if the data is larger than the
708 * max data size. The normal case however is just the opposite, and
709 * this function may be called multiple times, and will then actually
710 * defragment the data and send it out as one packet as soon as
711 * possible, but at a safer point in time
712 */
713 while (count) {
714 size = count;
715
716 /* Adjust data size to the max data size */
717 if (size > self->max_data_size)
718 size = self->max_data_size;
719
720 /*
721 * Do we already have a buffer ready for transmit, or do
722 * we need to allocate a new frame
723 */
724 if (skb) {
725 /*
726 * Any room for more data at the end of the current
727 * transmit buffer? Cannot use skb_tailroom, since
728 * dev_alloc_skb gives us a larger skb than we
729 * requested
730 */
731 if ((tailroom = (self->max_data_size-skb->len)) > 0) {
732 /* Adjust data to tailroom */
733 if (size > tailroom)
734 size = tailroom;
735 } else {
736 /*
737 * Current transmit frame is full, so break
738 * out, so we can send it as soon as possible
739 */
740 break;
741 }
742 } else {
743 /* Prepare a full sized frame */
744 skb = dev_alloc_skb(self->max_data_size+
745 self->max_header_size);
746 if (!skb) {
747 restore_flags(flags);
748 return -ENOBUFS;
749 }
750 skb_reserve(skb, self->max_header_size);
751 self->tx_skb = skb;
752 }
753
754 /* Copy data */
755 if (from_user)
756 copy_from_user(skb_put(skb,size), buf+len, size);
757 else
758 memcpy(skb_put(skb,size), buf+len, size);
759
760 count -= size;
761 len += size;
762 }
763
764 restore_flags(flags);
765
766 /*
767 * Schedule a new thread which will transmit the frame as soon
768 * as possible, but at a safe point in time. We do this so the
769 * "user" can give us data multiple times, as PPP does (because of
770 * its 256 byte tx buffer). We will then defragment and send out
771 * all this data as one single packet.
772 */
773 queue_task(&self->tqueue, &tq_immediate);
774 mark_bh(IMMEDIATE_BH);
775
776 return len;
777 }
778
779 /*
780 * Function ircomm_tty_write_room (tty)
781 *
782 * This routine returns the numbers of characters the tty driver will
783 * accept for queuing to be written. This number is subject to change as
784 * output buffers get emptied, or if the output flow control is acted.
785 */
786 static int ircomm_tty_write_room(struct tty_struct *tty)
787 {
788 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
789 unsigned long flags;
790 int ret;
791
792 ASSERT(self != NULL, return -1;);
793 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
794
795 /* Check if we are allowed to transmit any data */
796 if (tty->hw_stopped)
797 ret = 0;
798 else {
799 save_flags(flags);
800 cli();
801 if (self->tx_skb)
802 ret = self->max_data_size - self->tx_skb->len;
803 else
804 ret = self->max_data_size;
805 restore_flags(flags);
806 }
807 IRDA_DEBUG(2, __FUNCTION__ "(), ret=%d\n", ret);
808
809 return ret;
810 }
811
812 /*
813 * Function ircomm_tty_wait_until_sent (tty, timeout)
814 *
815 * This routine waits until the device has written out all of the
816 * characters in its transmitter FIFO.
817 */
818 static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
819 {
820 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
821 unsigned long orig_jiffies, poll_time;
822
823 IRDA_DEBUG(2, __FUNCTION__ "()\n");
824
825 ASSERT(self != NULL, return;);
826 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
827
828 orig_jiffies = jiffies;
829
830 /* Set poll time to 200 ms */
831 poll_time = IRDA_MIN(timeout, MSECS_TO_JIFFIES(200));
832
833 while (self->tx_skb && self->tx_skb->len) {
834 current->state = TASK_INTERRUPTIBLE;
835 schedule_timeout(poll_time);
836 if (signal_pending(current))
837 break;
838 if (timeout && time_after(jiffies, orig_jiffies + timeout))
839 break;
840 }
841 current->state = TASK_RUNNING;
842 }
843
844 /*
845 * Function ircomm_tty_throttle (tty)
846 *
847 * This routine notifies the tty driver that input buffers for the line
848 * discipline are close to full, and it should somehow signal that no
849 * more characters should be sent to the tty.
850 */
851 static void ircomm_tty_throttle(struct tty_struct *tty)
852 {
853 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
854
855 IRDA_DEBUG(2, __FUNCTION__ "()\n");
856
857 ASSERT(self != NULL, return;);
858 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
859
860 /* Software flow control? */
861 if (I_IXOFF(tty))
862 ircomm_tty_send_xchar(tty, STOP_CHAR(tty));
863
864 /* Hardware flow control? */
865 if (tty->termios->c_cflag & CRTSCTS) {
866 self->settings.dte &= ~IRCOMM_RTS;
867 self->settings.dte |= IRCOMM_DELTA_RTS;
868
869 ircomm_param_request(self, IRCOMM_DTE, TRUE);
870 }
871
872 ircomm_flow_request(self->ircomm, FLOW_STOP);
873 }
874
875 /*
876 * Function ircomm_tty_unthrottle (tty)
877 *
878 * This routine notifies the tty drivers that it should signals that
879 * characters can now be sent to the tty without fear of overrunning the
880 * input buffers of the line disciplines.
881 */
882 static void ircomm_tty_unthrottle(struct tty_struct *tty)
883 {
884 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
885
886 IRDA_DEBUG(2, __FUNCTION__ "()\n");
887
888 ASSERT(self != NULL, return;);
889 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
890
891 /* Using software flow control? */
892 if (I_IXOFF(tty)) {
893 ircomm_tty_send_xchar(tty, START_CHAR(tty));
894 }
895
896 /* Using hardware flow control? */
897 if (tty->termios->c_cflag & CRTSCTS) {
898 self->settings.dte |= (IRCOMM_RTS|IRCOMM_DELTA_RTS);
899
900 ircomm_param_request(self, IRCOMM_DTE, TRUE);
901 IRDA_DEBUG(1, __FUNCTION__"(), FLOW_START\n");
902 }
903 ircomm_flow_request(self->ircomm, FLOW_START);
904 }
905
906 /*
907 * Function ircomm_tty_chars_in_buffer (tty)
908 *
909 * Indicates if there are any data in the buffer
910 *
911 */
912 static int ircomm_tty_chars_in_buffer(struct tty_struct *tty)
913 {
914 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
915 unsigned long flags;
916 int len = 0;
917
918 ASSERT(self != NULL, return -1;);
919 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
920
921 save_flags(flags);
922 cli();
923
924 if (self->tx_skb)
925 len = self->tx_skb->len;
926
927 restore_flags(flags);
928
929 return len;
930 }
931
932 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
933 {
934 unsigned long flags;
935
936 ASSERT(self != NULL, return;);
937 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
938
939 IRDA_DEBUG(0, __FUNCTION__ "()\n");
940
941 if (!(self->flags & ASYNC_INITIALIZED))
942 return;
943
944 save_flags(flags);
945 cli();
946
947 del_timer(&self->watchdog_timer);
948
949 /* Free parameter buffer */
950 if (self->ctrl_skb) {
951 dev_kfree_skb(self->ctrl_skb);
952 self->ctrl_skb = NULL;
953 }
954
955 /* Free transmit buffer */
956 if (self->tx_skb) {
957 dev_kfree_skb(self->tx_skb);
958 self->tx_skb = NULL;
959 }
960
961 ircomm_tty_detach_cable(self);
962
963 if (self->ircomm) {
964 ircomm_close(self->ircomm);
965 self->ircomm = NULL;
966 }
967 self->flags &= ~ASYNC_INITIALIZED;
968
969 restore_flags(flags);
970 }
971
972 /*
973 * Function ircomm_tty_hangup (tty)
974 *
975 * This routine notifies the tty driver that it should hangup the tty
976 * device.
977 *
978 */
979 static void ircomm_tty_hangup(struct tty_struct *tty)
980 {
981 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
982
983 IRDA_DEBUG(0, __FUNCTION__"()\n");
984
985 ASSERT(self != NULL, return;);
986 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
987
988 if (!tty)
989 return;
990
991 /* ircomm_tty_flush_buffer(tty); */
992 ircomm_tty_shutdown(self);
993
994 self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
995 self->tty = 0;
996 self->open_count = 0;
997 wake_up_interruptible(&self->open_wait);
998 }
999
1000 /*
1001 * Function ircomm_tty_send_xchar (tty, ch)
1002 *
1003 * This routine is used to send a high-priority XON/XOFF character to
1004 * the device.
1005 */
1006 static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch)
1007 {
1008 IRDA_DEBUG(0, __FUNCTION__"(), not impl\n");
1009 }
1010
1011 /*
1012 * Function ircomm_tty_start (tty)
1013 *
1014 * This routine notifies the tty driver that it resume sending
1015 * characters to the tty device.
1016 */
1017 void ircomm_tty_start(struct tty_struct *tty)
1018 {
1019 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1020
1021 ircomm_flow_request(self->ircomm, FLOW_START);
1022 }
1023
1024 /*
1025 * Function ircomm_tty_stop (tty)
1026 *
1027 * This routine notifies the tty driver that it should stop outputting
1028 * characters to the tty device.
1029 */
1030 void ircomm_tty_stop(struct tty_struct *tty)
1031 {
1032 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1033
1034 ASSERT(self != NULL, return;);
1035 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1036
1037 ircomm_flow_request(self->ircomm, FLOW_STOP);
1038 }
1039
1040 /*
1041 * Function ircomm_check_modem_status (self)
1042 *
1043 * Check for any changes in the DCE's line settings. This function should
1044 * be called whenever the dce parameter settings changes, to update the
1045 * flow control settings and other things
1046 */
1047 void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
1048 {
1049 struct tty_struct *tty;
1050 int status;
1051
1052 IRDA_DEBUG(0, __FUNCTION__ "()\n");
1053
1054 ASSERT(self != NULL, return;);
1055 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1056
1057 tty = self->tty;
1058
1059 status = self->settings.dce;
1060
1061 if (status & IRCOMM_DCE_DELTA_ANY) {
1062 /*wake_up_interruptible(&self->delta_msr_wait);*/
1063 }
1064 if ((self->flags & ASYNC_CHECK_CD) && (status & IRCOMM_DELTA_CD)) {
1065 IRDA_DEBUG(2, __FUNCTION__
1066 "(), ircomm%d CD now %s...\n", self->line,
1067 (status & IRCOMM_CD) ? "on" : "off");
1068
1069 if (status & IRCOMM_CD) {
1070 wake_up_interruptible(&self->open_wait);
1071 } else if (!((self->flags & ASYNC_CALLOUT_ACTIVE) &&
1072 (self->flags & ASYNC_CALLOUT_NOHUP)))
1073 {
1074 IRDA_DEBUG(2, __FUNCTION__
1075 "(), Doing serial hangup..\n");
1076 if (tty)
1077 tty_hangup(tty);
1078
1079 /* Hangup will remote the tty, so better break out */
1080 return;
1081 }
1082 }
1083 if (self->flags & ASYNC_CTS_FLOW) {
1084 if (tty->hw_stopped) {
1085 if (status & IRCOMM_CTS) {
1086 IRDA_DEBUG(2, __FUNCTION__
1087 "(), CTS tx start...\n");
1088 tty->hw_stopped = 0;
1089
1090 /* Wake up processes blocked on open */
1091 wake_up_interruptible(&self->open_wait);
1092
1093 queue_task(&self->tqueue, &tq_immediate);
1094 mark_bh(IMMEDIATE_BH);
1095 return;
1096 }
1097 } else {
1098 if (!(status & IRCOMM_CTS)) {
1099 IRDA_DEBUG(2, __FUNCTION__
1100 "(), CTS tx stop...\n");
1101 tty->hw_stopped = 1;
1102 }
1103 }
1104 }
1105 }
1106
1107 /*
1108 * Function ircomm_tty_data_indication (instance, sap, skb)
1109 *
1110 * Handle incoming data, and deliver it to the line discipline
1111 *
1112 */
1113 static int ircomm_tty_data_indication(void *instance, void *sap,
1114 struct sk_buff *skb)
1115 {
1116 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1117
1118 IRDA_DEBUG(2, __FUNCTION__"()\n");
1119
1120 ASSERT(self != NULL, return -1;);
1121 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1122 ASSERT(skb != NULL, return -1;);
1123
1124 if (!self->tty) {
1125 IRDA_DEBUG(0, __FUNCTION__ "(), no tty!\n");
1126 dev_kfree_skb(skb);
1127 return 0;
1128 }
1129
1130 /*
1131 * If we receive data when hardware is stopped then something is wrong.
1132 * We try to poll the peers line settings to check if we are up todate.
1133 * Devices like WinCE can do this, and since they don't send any
1134 * params, we can just as well declare the hardware for running.
1135 */
1136 if (self->tty->hw_stopped && (self->flow == FLOW_START)) {
1137 IRDA_DEBUG(0, __FUNCTION__ "(), polling for line settings!\n");
1138 ircomm_param_request(self, IRCOMM_POLL, TRUE);
1139
1140 /* We can just as well declare the hardware for running */
1141 ircomm_tty_send_initial_parameters(self);
1142 ircomm_tty_link_established(self);
1143 }
1144
1145 /*
1146 * Just give it over to the line discipline. There is no need to
1147 * involve the flip buffers, since we are not running in an interrupt
1148 * handler
1149 */
1150 self->tty->ldisc.receive_buf(self->tty, skb->data, NULL, skb->len);
1151 dev_kfree_skb(skb);
1152
1153 return 0;
1154 }
1155
1156 /*
1157 * Function ircomm_tty_control_indication (instance, sap, skb)
1158 *
1159 * Parse all incoming parameters (easy!)
1160 *
1161 */
1162 static int ircomm_tty_control_indication(void *instance, void *sap,
1163 struct sk_buff *skb)
1164 {
1165 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1166 int clen;
1167
1168 IRDA_DEBUG(4, __FUNCTION__"()\n");
1169
1170 ASSERT(self != NULL, return -1;);
1171 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1172 ASSERT(skb != NULL, return -1;);
1173
1174 clen = skb->data[0];
1175
1176 irda_param_extract_all(self, skb->data+1, IRDA_MIN(skb->len-1, clen),
1177 &ircomm_param_info);
1178 dev_kfree_skb(skb);
1179
1180 return 0;
1181 }
1182
1183 /*
1184 * Function ircomm_tty_flow_indication (instance, sap, cmd)
1185 *
1186 * This function is called by IrTTP when it wants us to slow down the
1187 * transmission of data. We just mark the hardware as stopped, and wait
1188 * for IrTTP to notify us that things are OK again.
1189 */
1190 static void ircomm_tty_flow_indication(void *instance, void *sap,
1191 LOCAL_FLOW cmd)
1192 {
1193 struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1194 struct tty_struct *tty;
1195
1196 ASSERT(self != NULL, return;);
1197 ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1198
1199 tty = self->tty;
1200
1201 switch (cmd) {
1202 case FLOW_START:
1203 IRDA_DEBUG(2, __FUNCTION__ "(), hw start!\n");
1204 tty->hw_stopped = 0;
1205
1206 /* ircomm_tty_do_softint will take care of the rest */
1207 queue_task(&self->tqueue, &tq_immediate);
1208 mark_bh(IMMEDIATE_BH);
1209 break;
1210 default: /* If we get here, something is very wrong, better stop */
1211 case FLOW_STOP:
1212 IRDA_DEBUG(2, __FUNCTION__ "(), hw stopped!\n");
1213 tty->hw_stopped = 1;
1214 break;
1215 }
1216 self->flow = cmd;
1217 }
1218
1219 static int ircomm_tty_line_info(struct ircomm_tty_cb *self, char *buf)
1220 {
1221 int ret=0;
1222
1223 ret += sprintf(buf+ret, "State: %s\n", ircomm_tty_state[self->state]);
1224
1225 ret += sprintf(buf+ret, "Service type: ");
1226 if (self->service_type & IRCOMM_9_WIRE)
1227 ret += sprintf(buf+ret, "9_WIRE");
1228 else if (self->service_type & IRCOMM_3_WIRE)
1229 ret += sprintf(buf+ret, "3_WIRE");
1230 else if (self->service_type & IRCOMM_3_WIRE_RAW)
1231 ret += sprintf(buf+ret, "3_WIRE_RAW");
1232 else
1233 ret += sprintf(buf+ret, "No common service type!\n");
1234 ret += sprintf(buf+ret, "\n");
1235
1236 ret += sprintf(buf+ret, "Port name: %s\n", self->settings.port_name);
1237
1238 ret += sprintf(buf+ret, "DTE status: ");
1239 if (self->settings.dte & IRCOMM_RTS)
1240 ret += sprintf(buf+ret, "RTS|");
1241 if (self->settings.dte & IRCOMM_DTR)
1242 ret += sprintf(buf+ret, "DTR|");
1243 if (self->settings.dte)
1244 ret--; /* remove the last | */
1245 ret += sprintf(buf+ret, "\n");
1246
1247 ret += sprintf(buf+ret, "DCE status: ");
1248 if (self->settings.dce & IRCOMM_CTS)
1249 ret += sprintf(buf+ret, "CTS|");
1250 if (self->settings.dce & IRCOMM_DSR)
1251 ret += sprintf(buf+ret, "DSR|");
1252 if (self->settings.dce & IRCOMM_CD)
1253 ret += sprintf(buf+ret, "CD|");
1254 if (self->settings.dce & IRCOMM_RI)
1255 ret += sprintf(buf+ret, "RI|");
1256 if (self->settings.dce)
1257 ret--; /* remove the last | */
1258 ret += sprintf(buf+ret, "\n");
1259
1260 ret += sprintf(buf+ret, "Configuration: ");
1261 if (!self->settings.null_modem)
1262 ret += sprintf(buf+ret, "DTE <-> DCE\n");
1263 else
1264 ret += sprintf(buf+ret,
1265 "DTE <-> DTE (null modem emulation)\n");
1266
1267 ret += sprintf(buf+ret, "Data rate: %d\n", self->settings.data_rate);
1268
1269 ret += sprintf(buf+ret, "Flow control: ");
1270 if (self->settings.flow_control & IRCOMM_XON_XOFF_IN)
1271 ret += sprintf(buf+ret, "XON_XOFF_IN|");
1272 if (self->settings.flow_control & IRCOMM_XON_XOFF_OUT)
1273 ret += sprintf(buf+ret, "XON_XOFF_OUT|");
1274 if (self->settings.flow_control & IRCOMM_RTS_CTS_IN)
1275 ret += sprintf(buf+ret, "RTS_CTS_IN|");
1276 if (self->settings.flow_control & IRCOMM_RTS_CTS_OUT)
1277 ret += sprintf(buf+ret, "RTS_CTS_OUT|");
1278 if (self->settings.flow_control & IRCOMM_DSR_DTR_IN)
1279 ret += sprintf(buf+ret, "DSR_DTR_IN|");
1280 if (self->settings.flow_control & IRCOMM_DSR_DTR_OUT)
1281 ret += sprintf(buf+ret, "DSR_DTR_OUT|");
1282 if (self->settings.flow_control & IRCOMM_ENQ_ACK_IN)
1283 ret += sprintf(buf+ret, "ENQ_ACK_IN|");
1284 if (self->settings.flow_control & IRCOMM_ENQ_ACK_OUT)
1285 ret += sprintf(buf+ret, "ENQ_ACK_OUT|");
1286 if (self->settings.flow_control)
1287 ret--; /* remove the last | */
1288 ret += sprintf(buf+ret, "\n");
1289
1290 ret += sprintf(buf+ret, "Flags: ");
1291 if (self->flags & ASYNC_CTS_FLOW)
1292 ret += sprintf(buf+ret, "ASYNC_CTS_FLOW|");
1293 if (self->flags & ASYNC_CHECK_CD)
1294 ret += sprintf(buf+ret, "ASYNC_CHECK_CD|");
1295 if (self->flags & ASYNC_INITIALIZED)
1296 ret += sprintf(buf+ret, "ASYNC_INITIALIZED|");
1297 if (self->flags & ASYNC_LOW_LATENCY)
1298 ret += sprintf(buf+ret, "ASYNC_LOW_LATENCY|");
1299 if (self->flags & ASYNC_CLOSING)
1300 ret += sprintf(buf+ret, "ASYNC_CLOSING|");
1301 if (self->flags & ASYNC_NORMAL_ACTIVE)
1302 ret += sprintf(buf+ret, "ASYNC_NORMAL_ACTIVE|");
1303 if (self->flags & ASYNC_CALLOUT_ACTIVE)
1304 ret += sprintf(buf+ret, "ASYNC_CALLOUT_ACTIVE|");
1305 if (self->flags)
1306 ret--; /* remove the last | */
1307 ret += sprintf(buf+ret, "\n");
1308
1309 ret += sprintf(buf+ret, "Role: %s\n", self->client ?
1310 "client" : "server");
1311 ret += sprintf(buf+ret, "Open count: %d\n", self->open_count);
1312 ret += sprintf(buf+ret, "Max data size: %d\n", self->max_data_size);
1313 ret += sprintf(buf+ret, "Max header size: %d\n", self->max_header_size);
1314
1315 if (self->tty)
1316 ret += sprintf(buf+ret, "Hardware: %s\n",
1317 self->tty->hw_stopped ? "Stopped" : "Running");
1318
1319 ret += sprintf(buf+ret, "\n");
1320 return ret;
1321 }
1322
1323
1324 /*
1325 * Function ircomm_tty_read_proc (buf, start, offset, len, eof, unused)
1326 *
1327 *
1328 *
1329 */
1330 #ifdef CONFIG_PROC_FS
1331 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
1332 int *eof, void *unused)
1333 {
1334 struct ircomm_tty_cb *self;
1335 int count = 0, l;
1336 off_t begin = 0;
1337
1338 self = (struct ircomm_tty_cb *) hashbin_get_first(ircomm_tty);
1339 while ((self != NULL) && (count < 4000)) {
1340 if (self->magic != IRCOMM_TTY_MAGIC)
1341 return 0;
1342
1343 l = ircomm_tty_line_info(self, buf + count);
1344 count += l;
1345 if (count+begin > offset+len)
1346 goto done;
1347 if (count+begin < offset) {
1348 begin += count;
1349 count = 0;
1350 }
1351
1352 self = (struct ircomm_tty_cb *) hashbin_get_next(ircomm_tty);
1353 }
1354 *eof = 1;
1355 done:
1356 if (offset >= count+begin)
1357 return 0;
1358 *start = buf + (offset-begin);
1359 return ((len < begin+count-offset) ? len : begin+count-offset);
1360 }
1361 #endif /* CONFIG_PROC_FS */
1362
1363 #ifdef MODULE
1364 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
1365 MODULE_DESCRIPTION("IrCOMM serial TTY driver");
1366
1367 int init_module(void)
1368 {
1369 return ircomm_tty_init();
1370 }
1371
1372 void cleanup_module(void)
1373 {
1374 ircomm_tty_cleanup();
1375 }
1376
1377 #endif /* MODULE */
1378
1379
1380
1381
1382