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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  *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
15  *
16  *     This program is free software; you can redistribute it and/or
17  *     modify it under the terms of the GNU General Public License as
18  *     published by the Free Software Foundation; either version 2 of
19  *     the License, or (at your option) any later version.
20  *
21  *     This program is distributed in the hope that it will be useful,
22  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
23  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24  *     GNU General Public License for more details.
25  *
26  *     You should have received a copy of the GNU General Public License
27  *     along with this program; if not, write to the Free Software
28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29  *     MA 02111-1307 USA
30  *
31  ********************************************************************/
32 
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 #include <linux/device.h>		/* for MODULE_ALIAS_CHARDEV_MAJOR */
41 
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,
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(struct work_struct *work);
65 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self);
66 static void ircomm_tty_stop(struct tty_struct *tty);
67 
68 static int ircomm_tty_data_indication(void *instance, void *sap,
69 				      struct sk_buff *skb);
70 static int ircomm_tty_control_indication(void *instance, void *sap,
71 					 struct sk_buff *skb);
72 static void ircomm_tty_flow_indication(void *instance, void *sap,
73 				       LOCAL_FLOW cmd);
74 #ifdef CONFIG_PROC_FS
75 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
76 				int *eof, void *unused);
77 #endif /* CONFIG_PROC_FS */
78 static struct tty_driver *driver;
79 
80 static hashbin_t *ircomm_tty = NULL;
81 
82 static const struct tty_operations ops = {
83 	.open            = ircomm_tty_open,
84 	.close           = ircomm_tty_close,
85 	.write           = ircomm_tty_write,
86 	.write_room      = ircomm_tty_write_room,
87 	.chars_in_buffer = ircomm_tty_chars_in_buffer,
88 	.flush_buffer    = ircomm_tty_flush_buffer,
89 	.ioctl           = ircomm_tty_ioctl,	/* ircomm_tty_ioctl.c */
90 	.tiocmget        = ircomm_tty_tiocmget,	/* ircomm_tty_ioctl.c */
91 	.tiocmset        = ircomm_tty_tiocmset,	/* ircomm_tty_ioctl.c */
92 	.throttle        = ircomm_tty_throttle,
93 	.unthrottle      = ircomm_tty_unthrottle,
94 	.send_xchar      = ircomm_tty_send_xchar,
95 	.set_termios     = ircomm_tty_set_termios,
96 	.stop            = ircomm_tty_stop,
97 	.start           = ircomm_tty_start,
98 	.hangup          = ircomm_tty_hangup,
99 	.wait_until_sent = ircomm_tty_wait_until_sent,
100 #ifdef CONFIG_PROC_FS
101 	.read_proc       = ircomm_tty_read_proc,
102 #endif /* CONFIG_PROC_FS */
103 };
104 
105 /*
106  * Function ircomm_tty_init()
107  *
108  *    Init IrCOMM TTY layer/driver
109  *
110  */
ircomm_tty_init(void)111 static int __init ircomm_tty_init(void)
112 {
113 	driver = alloc_tty_driver(IRCOMM_TTY_PORTS);
114 	if (!driver)
115 		return -ENOMEM;
116 	ircomm_tty = hashbin_new(HB_LOCK);
117 	if (ircomm_tty == NULL) {
118 		IRDA_ERROR("%s(), can't allocate hashbin!\n", __func__);
119 		put_tty_driver(driver);
120 		return -ENOMEM;
121 	}
122 
123 	driver->owner		= THIS_MODULE;
124 	driver->driver_name     = "ircomm";
125 	driver->name            = "ircomm";
126 	driver->major           = IRCOMM_TTY_MAJOR;
127 	driver->minor_start     = IRCOMM_TTY_MINOR;
128 	driver->type            = TTY_DRIVER_TYPE_SERIAL;
129 	driver->subtype         = SERIAL_TYPE_NORMAL;
130 	driver->init_termios    = tty_std_termios;
131 	driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
132 	driver->flags           = TTY_DRIVER_REAL_RAW;
133 	tty_set_operations(driver, &ops);
134 	if (tty_register_driver(driver)) {
135 		IRDA_ERROR("%s(): Couldn't register serial driver\n",
136 			   __func__);
137 		put_tty_driver(driver);
138 		return -1;
139 	}
140 	return 0;
141 }
142 
__ircomm_tty_cleanup(struct ircomm_tty_cb * self)143 static void __exit __ircomm_tty_cleanup(struct ircomm_tty_cb *self)
144 {
145 	IRDA_DEBUG(0, "%s()\n", __func__ );
146 
147 	IRDA_ASSERT(self != NULL, return;);
148 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
149 
150 	ircomm_tty_shutdown(self);
151 
152 	self->magic = 0;
153 	kfree(self);
154 }
155 
156 /*
157  * Function ircomm_tty_cleanup ()
158  *
159  *    Remove IrCOMM TTY layer/driver
160  *
161  */
ircomm_tty_cleanup(void)162 static void __exit ircomm_tty_cleanup(void)
163 {
164 	int ret;
165 
166 	IRDA_DEBUG(4, "%s()\n", __func__ );
167 
168 	ret = tty_unregister_driver(driver);
169 	if (ret) {
170 		IRDA_ERROR("%s(), failed to unregister driver\n",
171 			   __func__);
172 		return;
173 	}
174 
175 	hashbin_delete(ircomm_tty, (FREE_FUNC) __ircomm_tty_cleanup);
176 	put_tty_driver(driver);
177 }
178 
179 /*
180  * Function ircomm_startup (self)
181  *
182  *
183  *
184  */
ircomm_tty_startup(struct ircomm_tty_cb * self)185 static int ircomm_tty_startup(struct ircomm_tty_cb *self)
186 {
187 	notify_t notify;
188 	int ret = -ENODEV;
189 
190 	IRDA_DEBUG(2, "%s()\n", __func__ );
191 
192 	IRDA_ASSERT(self != NULL, return -1;);
193 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
194 
195 	/* Check if already open */
196 	if (test_and_set_bit(ASYNC_B_INITIALIZED, &self->flags)) {
197 		IRDA_DEBUG(2, "%s(), already open so break out!\n", __func__ );
198 		return 0;
199 	}
200 
201 	/* Register with IrCOMM */
202 	irda_notify_init(&notify);
203 	/* These callbacks we must handle ourselves */
204 	notify.data_indication       = ircomm_tty_data_indication;
205 	notify.udata_indication      = ircomm_tty_control_indication;
206 	notify.flow_indication       = ircomm_tty_flow_indication;
207 
208 	/* Use the ircomm_tty interface for these ones */
209 	notify.disconnect_indication = ircomm_tty_disconnect_indication;
210 	notify.connect_confirm       = ircomm_tty_connect_confirm;
211 	notify.connect_indication    = ircomm_tty_connect_indication;
212 	strlcpy(notify.name, "ircomm_tty", sizeof(notify.name));
213 	notify.instance = self;
214 
215 	if (!self->ircomm) {
216 		self->ircomm = ircomm_open(&notify, self->service_type,
217 					   self->line);
218 	}
219 	if (!self->ircomm)
220 		goto err;
221 
222 	self->slsap_sel = self->ircomm->slsap_sel;
223 
224 	/* Connect IrCOMM link with remote device */
225 	ret = ircomm_tty_attach_cable(self);
226 	if (ret < 0) {
227 		IRDA_ERROR("%s(), error attaching cable!\n", __func__);
228 		goto err;
229 	}
230 
231 	return 0;
232 err:
233 	clear_bit(ASYNC_B_INITIALIZED, &self->flags);
234 	return ret;
235 }
236 
237 /*
238  * Function ircomm_block_til_ready (self, filp)
239  *
240  *
241  *
242  */
ircomm_tty_block_til_ready(struct ircomm_tty_cb * self,struct file * filp)243 static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
244 				      struct file *filp)
245 {
246 	DECLARE_WAITQUEUE(wait, current);
247 	int		retval;
248 	int		do_clocal = 0, extra_count = 0;
249 	unsigned long	flags;
250 	struct tty_struct *tty;
251 
252 	IRDA_DEBUG(2, "%s()\n", __func__ );
253 
254 	tty = self->tty;
255 
256 	/*
257 	 * If non-blocking mode is set, or the port is not enabled,
258 	 * then make the check up front and then exit.
259 	 */
260 	if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
261 		/* nonblock mode is set or port is not enabled */
262 		self->flags |= ASYNC_NORMAL_ACTIVE;
263 		IRDA_DEBUG(1, "%s(), O_NONBLOCK requested!\n", __func__ );
264 		return 0;
265 	}
266 
267 	if (tty->termios->c_cflag & CLOCAL) {
268 		IRDA_DEBUG(1, "%s(), doing CLOCAL!\n", __func__ );
269 		do_clocal = 1;
270 	}
271 
272 	/* Wait for carrier detect and the line to become
273 	 * free (i.e., not in use by the callout).  While we are in
274 	 * this loop, self->open_count is dropped by one, so that
275 	 * mgsl_close() knows when to free things.  We restore it upon
276 	 * exit, either normal or abnormal.
277 	 */
278 
279 	retval = 0;
280 	add_wait_queue(&self->open_wait, &wait);
281 
282 	IRDA_DEBUG(2, "%s(%d):block_til_ready before block on %s open_count=%d\n",
283 	      __FILE__,__LINE__, tty->driver->name, self->open_count );
284 
285 	/* As far as I can see, we protect open_count - Jean II */
286 	spin_lock_irqsave(&self->spinlock, flags);
287 	if (!tty_hung_up_p(filp)) {
288 		extra_count = 1;
289 		self->open_count--;
290 	}
291 	spin_unlock_irqrestore(&self->spinlock, flags);
292 	self->blocked_open++;
293 
294 	while (1) {
295 		if (tty->termios->c_cflag & CBAUD) {
296 			/* Here, we use to lock those two guys, but
297 			 * as ircomm_param_request() does it itself,
298 			 * I don't see the point (and I see the deadlock).
299 			 * Jean II */
300 			self->settings.dte |= IRCOMM_RTS + IRCOMM_DTR;
301 
302 			ircomm_param_request(self, IRCOMM_DTE, TRUE);
303 		}
304 
305 		current->state = TASK_INTERRUPTIBLE;
306 
307 		if (tty_hung_up_p(filp) ||
308 		    !test_bit(ASYNC_B_INITIALIZED, &self->flags)) {
309 			retval = (self->flags & ASYNC_HUP_NOTIFY) ?
310 					-EAGAIN : -ERESTARTSYS;
311 			break;
312 		}
313 
314 		/*
315 		 * Check if link is ready now. Even if CLOCAL is
316 		 * specified, we cannot return before the IrCOMM link is
317 		 * ready
318 		 */
319 		if (!test_bit(ASYNC_B_CLOSING, &self->flags) &&
320 		    (do_clocal || (self->settings.dce & IRCOMM_CD)) &&
321 		    self->state == IRCOMM_TTY_READY)
322 		{
323 			break;
324 		}
325 
326 		if (signal_pending(current)) {
327 			retval = -ERESTARTSYS;
328 			break;
329 		}
330 
331 		IRDA_DEBUG(1, "%s(%d):block_til_ready blocking on %s open_count=%d\n",
332 		      __FILE__,__LINE__, tty->driver->name, self->open_count );
333 
334 		schedule();
335 	}
336 
337 	__set_current_state(TASK_RUNNING);
338 	remove_wait_queue(&self->open_wait, &wait);
339 
340 	if (extra_count) {
341 		/* ++ is not atomic, so this should be protected - Jean II */
342 		spin_lock_irqsave(&self->spinlock, flags);
343 		self->open_count++;
344 		spin_unlock_irqrestore(&self->spinlock, flags);
345 	}
346 	self->blocked_open--;
347 
348 	IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n",
349 	      __FILE__,__LINE__, tty->driver->name, self->open_count);
350 
351 	if (!retval)
352 		self->flags |= ASYNC_NORMAL_ACTIVE;
353 
354 	return retval;
355 }
356 
357 /*
358  * Function ircomm_tty_open (tty, filp)
359  *
360  *    This routine is called when a particular tty device is opened. This
361  *    routine is mandatory; if this routine is not filled in, the attempted
362  *    open will fail with ENODEV.
363  */
ircomm_tty_open(struct tty_struct * tty,struct file * filp)364 static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
365 {
366 	struct ircomm_tty_cb *self;
367 	unsigned int line;
368 	unsigned long	flags;
369 	int ret;
370 
371 	IRDA_DEBUG(2, "%s()\n", __func__ );
372 
373 	line = tty->index;
374 	if (line >= IRCOMM_TTY_PORTS)
375 		return -ENODEV;
376 
377 	/* Check if instance already exists */
378 	self = hashbin_lock_find(ircomm_tty, line, NULL);
379 	if (!self) {
380 		/* No, so make new instance */
381 		self = kzalloc(sizeof(struct ircomm_tty_cb), GFP_KERNEL);
382 		if (self == NULL) {
383 			IRDA_ERROR("%s(), kmalloc failed!\n", __func__);
384 			return -ENOMEM;
385 		}
386 
387 		self->magic = IRCOMM_TTY_MAGIC;
388 		self->flow = FLOW_STOP;
389 
390 		self->line = line;
391 		INIT_WORK(&self->tqueue, ircomm_tty_do_softint);
392 		self->max_header_size = IRCOMM_TTY_HDR_UNINITIALISED;
393 		self->max_data_size = IRCOMM_TTY_DATA_UNINITIALISED;
394 		self->close_delay = 5*HZ/10;
395 		self->closing_wait = 30*HZ;
396 
397 		/* Init some important stuff */
398 		init_timer(&self->watchdog_timer);
399 		init_waitqueue_head(&self->open_wait);
400 		init_waitqueue_head(&self->close_wait);
401 		spin_lock_init(&self->spinlock);
402 
403 		/*
404 		 * Force TTY into raw mode by default which is usually what
405 		 * we want for IrCOMM and IrLPT. This way applications will
406 		 * not have to twiddle with printcap etc.
407 		 *
408 		 * Note this is completely usafe and doesn't work properly
409 		 */
410 		tty->termios->c_iflag = 0;
411 		tty->termios->c_oflag = 0;
412 
413 		/* Insert into hash */
414 		hashbin_insert(ircomm_tty, (irda_queue_t *) self, line, NULL);
415 	}
416 	/* ++ is not atomic, so this should be protected - Jean II */
417 	spin_lock_irqsave(&self->spinlock, flags);
418 	self->open_count++;
419 
420 	tty->driver_data = self;
421 	self->tty = tty;
422 	spin_unlock_irqrestore(&self->spinlock, flags);
423 
424 	IRDA_DEBUG(1, "%s(), %s%d, count = %d\n", __func__ , tty->driver->name,
425 		   self->line, self->open_count);
426 
427 	/* Not really used by us, but lets do it anyway */
428 	self->tty->low_latency = (self->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
429 
430 	/*
431 	 * If the port is the middle of closing, bail out now
432 	 */
433 	if (tty_hung_up_p(filp) ||
434 	    test_bit(ASYNC_B_CLOSING, &self->flags)) {
435 
436 		/* Hm, why are we blocking on ASYNC_CLOSING if we
437 		 * do return -EAGAIN/-ERESTARTSYS below anyway?
438 		 * IMHO it's either not needed in the first place
439 		 * or for some reason we need to make sure the async
440 		 * closing has been finished - if so, wouldn't we
441 		 * probably better sleep uninterruptible?
442 		 */
443 
444 		if (wait_event_interruptible(self->close_wait, !test_bit(ASYNC_B_CLOSING, &self->flags))) {
445 			IRDA_WARNING("%s - got signal while blocking on ASYNC_CLOSING!\n",
446 				     __func__);
447 			return -ERESTARTSYS;
448 		}
449 
450 #ifdef SERIAL_DO_RESTART
451 		return ((self->flags & ASYNC_HUP_NOTIFY) ?
452 			-EAGAIN : -ERESTARTSYS);
453 #else
454 		return -EAGAIN;
455 #endif
456 	}
457 
458 	/* Check if this is a "normal" ircomm device, or an irlpt device */
459 	if (line < 0x10) {
460 		self->service_type = IRCOMM_3_WIRE | IRCOMM_9_WIRE;
461 		self->settings.service_type = IRCOMM_9_WIRE; /* 9 wire as default */
462 		/* Jan Kiszka -> add DSR/RI -> Conform to IrCOMM spec */
463 		self->settings.dce = IRCOMM_CTS | IRCOMM_CD | IRCOMM_DSR | IRCOMM_RI; /* Default line settings */
464 		IRDA_DEBUG(2, "%s(), IrCOMM device\n", __func__ );
465 	} else {
466 		IRDA_DEBUG(2, "%s(), IrLPT device\n", __func__ );
467 		self->service_type = IRCOMM_3_WIRE_RAW;
468 		self->settings.service_type = IRCOMM_3_WIRE_RAW; /* Default */
469 	}
470 
471 	ret = ircomm_tty_startup(self);
472 	if (ret)
473 		return ret;
474 
475 	ret = ircomm_tty_block_til_ready(self, filp);
476 	if (ret) {
477 		IRDA_DEBUG(2,
478 		      "%s(), returning after block_til_ready with %d\n", __func__ ,
479 		      ret);
480 
481 		return ret;
482 	}
483 	return 0;
484 }
485 
486 /*
487  * Function ircomm_tty_close (tty, filp)
488  *
489  *    This routine is called when a particular tty device is closed.
490  *
491  */
ircomm_tty_close(struct tty_struct * tty,struct file * filp)492 static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
493 {
494 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
495 	unsigned long flags;
496 
497 	IRDA_DEBUG(0, "%s()\n", __func__ );
498 
499 	if (!tty)
500 		return;
501 
502 	IRDA_ASSERT(self != NULL, return;);
503 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
504 
505 	spin_lock_irqsave(&self->spinlock, flags);
506 
507 	if (tty_hung_up_p(filp)) {
508 		spin_unlock_irqrestore(&self->spinlock, flags);
509 
510 		IRDA_DEBUG(0, "%s(), returning 1\n", __func__ );
511 		return;
512 	}
513 
514 	if ((tty->count == 1) && (self->open_count != 1)) {
515 		/*
516 		 * Uh, oh.  tty->count is 1, which means that the tty
517 		 * structure will be freed.  state->count should always
518 		 * be one in these conditions.  If it's greater than
519 		 * one, we've got real problems, since it means the
520 		 * serial port won't be shutdown.
521 		 */
522 		IRDA_DEBUG(0, "%s(), bad serial port count; "
523 			   "tty->count is 1, state->count is %d\n", __func__ ,
524 			   self->open_count);
525 		self->open_count = 1;
526 	}
527 
528 	if (--self->open_count < 0) {
529 		IRDA_ERROR("%s(), bad serial port count for ttys%d: %d\n",
530 			   __func__, self->line, self->open_count);
531 		self->open_count = 0;
532 	}
533 	if (self->open_count) {
534 		spin_unlock_irqrestore(&self->spinlock, flags);
535 
536 		IRDA_DEBUG(0, "%s(), open count > 0\n", __func__ );
537 		return;
538 	}
539 
540 	/* Hum... Should be test_and_set_bit ??? - Jean II */
541 	set_bit(ASYNC_B_CLOSING, &self->flags);
542 
543 	/* We need to unlock here (we were unlocking at the end of this
544 	 * function), because tty_wait_until_sent() may schedule.
545 	 * I don't know if the rest should be protected somehow,
546 	 * so someone should check. - Jean II */
547 	spin_unlock_irqrestore(&self->spinlock, flags);
548 
549 	/*
550 	 * Now we wait for the transmit buffer to clear; and we notify
551 	 * the line discipline to only process XON/XOFF characters.
552 	 */
553 	tty->closing = 1;
554 	if (self->closing_wait != ASYNC_CLOSING_WAIT_NONE)
555 		tty_wait_until_sent(tty, self->closing_wait);
556 
557 	ircomm_tty_shutdown(self);
558 
559 	tty_driver_flush_buffer(tty);
560 	tty_ldisc_flush(tty);
561 
562 	tty->closing = 0;
563 	self->tty = NULL;
564 
565 	if (self->blocked_open) {
566 		if (self->close_delay)
567 			schedule_timeout_interruptible(self->close_delay);
568 		wake_up_interruptible(&self->open_wait);
569 	}
570 
571 	self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
572 	wake_up_interruptible(&self->close_wait);
573 }
574 
575 /*
576  * Function ircomm_tty_flush_buffer (tty)
577  *
578  *
579  *
580  */
ircomm_tty_flush_buffer(struct tty_struct * tty)581 static void ircomm_tty_flush_buffer(struct tty_struct *tty)
582 {
583 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
584 
585 	IRDA_ASSERT(self != NULL, return;);
586 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
587 
588 	/*
589 	 * Let do_softint() do this to avoid race condition with
590 	 * do_softint() ;-)
591 	 */
592 	schedule_work(&self->tqueue);
593 }
594 
595 /*
596  * Function ircomm_tty_do_softint (work)
597  *
598  *    We use this routine to give the write wakeup to the user at at a
599  *    safe time (as fast as possible after write have completed). This
600  *    can be compared to the Tx interrupt.
601  */
ircomm_tty_do_softint(struct work_struct * work)602 static void ircomm_tty_do_softint(struct work_struct *work)
603 {
604 	struct ircomm_tty_cb *self =
605 		container_of(work, struct ircomm_tty_cb, tqueue);
606 	struct tty_struct *tty;
607 	unsigned long flags;
608 	struct sk_buff *skb, *ctrl_skb;
609 
610 	IRDA_DEBUG(2, "%s()\n", __func__ );
611 
612 	if (!self || self->magic != IRCOMM_TTY_MAGIC)
613 		return;
614 
615 	tty = self->tty;
616 	if (!tty)
617 		return;
618 
619 	/* Unlink control buffer */
620 	spin_lock_irqsave(&self->spinlock, flags);
621 
622 	ctrl_skb = self->ctrl_skb;
623 	self->ctrl_skb = NULL;
624 
625 	spin_unlock_irqrestore(&self->spinlock, flags);
626 
627 	/* Flush control buffer if any */
628 	if(ctrl_skb) {
629 		if(self->flow == FLOW_START)
630 			ircomm_control_request(self->ircomm, ctrl_skb);
631 		/* Drop reference count - see ircomm_ttp_data_request(). */
632 		dev_kfree_skb(ctrl_skb);
633 	}
634 
635 	if (tty->hw_stopped)
636 		return;
637 
638 	/* Unlink transmit buffer */
639 	spin_lock_irqsave(&self->spinlock, flags);
640 
641 	skb = self->tx_skb;
642 	self->tx_skb = NULL;
643 
644 	spin_unlock_irqrestore(&self->spinlock, flags);
645 
646 	/* Flush transmit buffer if any */
647 	if (skb) {
648 		ircomm_tty_do_event(self, IRCOMM_TTY_DATA_REQUEST, skb, NULL);
649 		/* Drop reference count - see ircomm_ttp_data_request(). */
650 		dev_kfree_skb(skb);
651 	}
652 
653 	/* Check if user (still) wants to be waken up */
654 	tty_wakeup(tty);
655 }
656 
657 /*
658  * Function ircomm_tty_write (tty, buf, count)
659  *
660  *    This routine is called by the kernel to write a series of characters
661  *    to the tty device. The characters may come from user space or kernel
662  *    space. This routine will return the number of characters actually
663  *    accepted for writing. This routine is mandatory.
664  */
ircomm_tty_write(struct tty_struct * tty,const unsigned char * buf,int count)665 static int ircomm_tty_write(struct tty_struct *tty,
666 			    const unsigned char *buf, int count)
667 {
668 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
669 	unsigned long flags;
670 	struct sk_buff *skb;
671 	int tailroom = 0;
672 	int len = 0;
673 	int size;
674 
675 	IRDA_DEBUG(2, "%s(), count=%d, hw_stopped=%d\n", __func__ , count,
676 		   tty->hw_stopped);
677 
678 	IRDA_ASSERT(self != NULL, return -1;);
679 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
680 
681 	/* We may receive packets from the TTY even before we have finished
682 	 * our setup. Not cool.
683 	 * The problem is that we don't know the final header and data size
684 	 * to create the proper skb, so any skb we would create would have
685 	 * bogus header and data size, so need care.
686 	 * We use a bogus header size to safely detect this condition.
687 	 * Another problem is that hw_stopped was set to 0 way before it
688 	 * should be, so we would drop this skb. It should now be fixed.
689 	 * One option is to not accept data until we are properly setup.
690 	 * But, I suspect that when it happens, the ppp line discipline
691 	 * just "drops" the data, which might screw up connect scripts.
692 	 * The second option is to create a "safe skb", with large header
693 	 * and small size (see ircomm_tty_open() for values).
694 	 * We just need to make sure that when the real values get filled,
695 	 * we don't mess up the original "safe skb" (see tx_data_size).
696 	 * Jean II */
697 	if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED) {
698 		IRDA_DEBUG(1, "%s() : not initialised\n", __func__);
699 #ifdef IRCOMM_NO_TX_BEFORE_INIT
700 		/* We didn't consume anything, TTY will retry */
701 		return 0;
702 #endif
703 	}
704 
705 	if (count < 1)
706 		return 0;
707 
708 	/* Protect our manipulation of self->tx_skb and related */
709 	spin_lock_irqsave(&self->spinlock, flags);
710 
711 	/* Fetch current transmit buffer */
712 	skb = self->tx_skb;
713 
714 	/*
715 	 * Send out all the data we get, possibly as multiple fragmented
716 	 * frames, but this will only happen if the data is larger than the
717 	 * max data size. The normal case however is just the opposite, and
718 	 * this function may be called multiple times, and will then actually
719 	 * defragment the data and send it out as one packet as soon as
720 	 * possible, but at a safer point in time
721 	 */
722 	while (count) {
723 		size = count;
724 
725 		/* Adjust data size to the max data size */
726 		if (size > self->max_data_size)
727 			size = self->max_data_size;
728 
729 		/*
730 		 * Do we already have a buffer ready for transmit, or do
731 		 * we need to allocate a new frame
732 		 */
733 		if (skb) {
734 			/*
735 			 * Any room for more data at the end of the current
736 			 * transmit buffer? Cannot use skb_tailroom, since
737 			 * dev_alloc_skb gives us a larger skb than we
738 			 * requested
739 			 * Note : use tx_data_size, because max_data_size
740 			 * may have changed and we don't want to overwrite
741 			 * the skb. - Jean II
742 			 */
743 			if ((tailroom = (self->tx_data_size - skb->len)) > 0) {
744 				/* Adjust data to tailroom */
745 				if (size > tailroom)
746 					size = tailroom;
747 			} else {
748 				/*
749 				 * Current transmit frame is full, so break
750 				 * out, so we can send it as soon as possible
751 				 */
752 				break;
753 			}
754 		} else {
755 			/* Prepare a full sized frame */
756 			skb = alloc_skb(self->max_data_size+
757 					self->max_header_size,
758 					GFP_ATOMIC);
759 			if (!skb) {
760 				spin_unlock_irqrestore(&self->spinlock, flags);
761 				return -ENOBUFS;
762 			}
763 			skb_reserve(skb, self->max_header_size);
764 			self->tx_skb = skb;
765 			/* Remember skb size because max_data_size may
766 			 * change later on - Jean II */
767 			self->tx_data_size = self->max_data_size;
768 		}
769 
770 		/* Copy data */
771 		memcpy(skb_put(skb,size), buf + len, size);
772 
773 		count -= size;
774 		len += size;
775 	}
776 
777 	spin_unlock_irqrestore(&self->spinlock, flags);
778 
779 	/*
780 	 * Schedule a new thread which will transmit the frame as soon
781 	 * as possible, but at a safe point in time. We do this so the
782 	 * "user" can give us data multiple times, as PPP does (because of
783 	 * its 256 byte tx buffer). We will then defragment and send out
784 	 * all this data as one single packet.
785 	 */
786 	schedule_work(&self->tqueue);
787 
788 	return len;
789 }
790 
791 /*
792  * Function ircomm_tty_write_room (tty)
793  *
794  *    This routine returns the numbers of characters the tty driver will
795  *    accept for queuing to be written. This number is subject to change as
796  *    output buffers get emptied, or if the output flow control is acted.
797  */
ircomm_tty_write_room(struct tty_struct * tty)798 static int ircomm_tty_write_room(struct tty_struct *tty)
799 {
800 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
801 	unsigned long flags;
802 	int ret;
803 
804 	IRDA_ASSERT(self != NULL, return -1;);
805 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
806 
807 #ifdef IRCOMM_NO_TX_BEFORE_INIT
808 	/* max_header_size tells us if the channel is initialised or not. */
809 	if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED)
810 		/* Don't bother us yet */
811 		return 0;
812 #endif
813 
814 	/* Check if we are allowed to transmit any data.
815 	 * hw_stopped is the regular flow control.
816 	 * Jean II */
817 	if (tty->hw_stopped)
818 		ret = 0;
819 	else {
820 		spin_lock_irqsave(&self->spinlock, flags);
821 		if (self->tx_skb)
822 			ret = self->tx_data_size - self->tx_skb->len;
823 		else
824 			ret = self->max_data_size;
825 		spin_unlock_irqrestore(&self->spinlock, flags);
826 	}
827 	IRDA_DEBUG(2, "%s(), ret=%d\n", __func__ , ret);
828 
829 	return ret;
830 }
831 
832 /*
833  * Function ircomm_tty_wait_until_sent (tty, timeout)
834  *
835  *    This routine waits until the device has written out all of the
836  *    characters in its transmitter FIFO.
837  */
ircomm_tty_wait_until_sent(struct tty_struct * tty,int timeout)838 static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
839 {
840 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
841 	unsigned long orig_jiffies, poll_time;
842 	unsigned long flags;
843 
844 	IRDA_DEBUG(2, "%s()\n", __func__ );
845 
846 	IRDA_ASSERT(self != NULL, return;);
847 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
848 
849 	orig_jiffies = jiffies;
850 
851 	/* Set poll time to 200 ms */
852 	poll_time = IRDA_MIN(timeout, msecs_to_jiffies(200));
853 
854 	spin_lock_irqsave(&self->spinlock, flags);
855 	while (self->tx_skb && self->tx_skb->len) {
856 		spin_unlock_irqrestore(&self->spinlock, flags);
857 		schedule_timeout_interruptible(poll_time);
858 		spin_lock_irqsave(&self->spinlock, flags);
859 		if (signal_pending(current))
860 			break;
861 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
862 			break;
863 	}
864 	spin_unlock_irqrestore(&self->spinlock, flags);
865 	current->state = TASK_RUNNING;
866 }
867 
868 /*
869  * Function ircomm_tty_throttle (tty)
870  *
871  *    This routine notifies the tty driver that input buffers for the line
872  *    discipline are close to full, and it should somehow signal that no
873  *    more characters should be sent to the tty.
874  */
ircomm_tty_throttle(struct tty_struct * tty)875 static void ircomm_tty_throttle(struct tty_struct *tty)
876 {
877 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
878 
879 	IRDA_DEBUG(2, "%s()\n", __func__ );
880 
881 	IRDA_ASSERT(self != NULL, return;);
882 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
883 
884 	/* Software flow control? */
885 	if (I_IXOFF(tty))
886 		ircomm_tty_send_xchar(tty, STOP_CHAR(tty));
887 
888 	/* Hardware flow control? */
889 	if (tty->termios->c_cflag & CRTSCTS) {
890 		self->settings.dte &= ~IRCOMM_RTS;
891 		self->settings.dte |= IRCOMM_DELTA_RTS;
892 
893 		ircomm_param_request(self, IRCOMM_DTE, TRUE);
894 	}
895 
896 	ircomm_flow_request(self->ircomm, FLOW_STOP);
897 }
898 
899 /*
900  * Function ircomm_tty_unthrottle (tty)
901  *
902  *    This routine notifies the tty drivers that it should signals that
903  *    characters can now be sent to the tty without fear of overrunning the
904  *    input buffers of the line disciplines.
905  */
ircomm_tty_unthrottle(struct tty_struct * tty)906 static void ircomm_tty_unthrottle(struct tty_struct *tty)
907 {
908 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
909 
910 	IRDA_DEBUG(2, "%s()\n", __func__ );
911 
912 	IRDA_ASSERT(self != NULL, return;);
913 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
914 
915 	/* Using software flow control? */
916 	if (I_IXOFF(tty)) {
917 		ircomm_tty_send_xchar(tty, START_CHAR(tty));
918 	}
919 
920 	/* Using hardware flow control? */
921 	if (tty->termios->c_cflag & CRTSCTS) {
922 		self->settings.dte |= (IRCOMM_RTS|IRCOMM_DELTA_RTS);
923 
924 		ircomm_param_request(self, IRCOMM_DTE, TRUE);
925 		IRDA_DEBUG(1, "%s(), FLOW_START\n", __func__ );
926 	}
927 	ircomm_flow_request(self->ircomm, FLOW_START);
928 }
929 
930 /*
931  * Function ircomm_tty_chars_in_buffer (tty)
932  *
933  *    Indicates if there are any data in the buffer
934  *
935  */
ircomm_tty_chars_in_buffer(struct tty_struct * tty)936 static int ircomm_tty_chars_in_buffer(struct tty_struct *tty)
937 {
938 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
939 	unsigned long flags;
940 	int len = 0;
941 
942 	IRDA_ASSERT(self != NULL, return -1;);
943 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
944 
945 	spin_lock_irqsave(&self->spinlock, flags);
946 
947 	if (self->tx_skb)
948 		len = self->tx_skb->len;
949 
950 	spin_unlock_irqrestore(&self->spinlock, flags);
951 
952 	return len;
953 }
954 
ircomm_tty_shutdown(struct ircomm_tty_cb * self)955 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
956 {
957 	unsigned long flags;
958 
959 	IRDA_ASSERT(self != NULL, return;);
960 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
961 
962 	IRDA_DEBUG(0, "%s()\n", __func__ );
963 
964 	if (!test_and_clear_bit(ASYNC_B_INITIALIZED, &self->flags))
965 		return;
966 
967 	ircomm_tty_detach_cable(self);
968 
969 	spin_lock_irqsave(&self->spinlock, flags);
970 
971 	del_timer(&self->watchdog_timer);
972 
973 	/* Free parameter buffer */
974 	if (self->ctrl_skb) {
975 		dev_kfree_skb(self->ctrl_skb);
976 		self->ctrl_skb = NULL;
977 	}
978 
979 	/* Free transmit buffer */
980 	if (self->tx_skb) {
981 		dev_kfree_skb(self->tx_skb);
982 		self->tx_skb = NULL;
983 	}
984 
985 	if (self->ircomm) {
986 		ircomm_close(self->ircomm);
987 		self->ircomm = NULL;
988 	}
989 
990 	spin_unlock_irqrestore(&self->spinlock, flags);
991 }
992 
993 /*
994  * Function ircomm_tty_hangup (tty)
995  *
996  *    This routine notifies the tty driver that it should hangup the tty
997  *    device.
998  *
999  */
ircomm_tty_hangup(struct tty_struct * tty)1000 static void ircomm_tty_hangup(struct tty_struct *tty)
1001 {
1002 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1003 	unsigned long	flags;
1004 
1005 	IRDA_DEBUG(0, "%s()\n", __func__ );
1006 
1007 	IRDA_ASSERT(self != NULL, return;);
1008 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1009 
1010 	if (!tty)
1011 		return;
1012 
1013 	/* ircomm_tty_flush_buffer(tty); */
1014 	ircomm_tty_shutdown(self);
1015 
1016 	/* I guess we need to lock here - Jean II */
1017 	spin_lock_irqsave(&self->spinlock, flags);
1018 	self->flags &= ~ASYNC_NORMAL_ACTIVE;
1019 	self->tty = NULL;
1020 	self->open_count = 0;
1021 	spin_unlock_irqrestore(&self->spinlock, flags);
1022 
1023 	wake_up_interruptible(&self->open_wait);
1024 }
1025 
1026 /*
1027  * Function ircomm_tty_send_xchar (tty, ch)
1028  *
1029  *    This routine is used to send a high-priority XON/XOFF character to
1030  *    the device.
1031  */
ircomm_tty_send_xchar(struct tty_struct * tty,char ch)1032 static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch)
1033 {
1034 	IRDA_DEBUG(0, "%s(), not impl\n", __func__ );
1035 }
1036 
1037 /*
1038  * Function ircomm_tty_start (tty)
1039  *
1040  *    This routine notifies the tty driver that it resume sending
1041  *    characters to the tty device.
1042  */
ircomm_tty_start(struct tty_struct * tty)1043 void ircomm_tty_start(struct tty_struct *tty)
1044 {
1045 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1046 
1047 	ircomm_flow_request(self->ircomm, FLOW_START);
1048 }
1049 
1050 /*
1051  * Function ircomm_tty_stop (tty)
1052  *
1053  *     This routine notifies the tty driver that it should stop outputting
1054  *     characters to the tty device.
1055  */
ircomm_tty_stop(struct tty_struct * tty)1056 static void ircomm_tty_stop(struct tty_struct *tty)
1057 {
1058 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1059 
1060 	IRDA_ASSERT(self != NULL, return;);
1061 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1062 
1063 	ircomm_flow_request(self->ircomm, FLOW_STOP);
1064 }
1065 
1066 /*
1067  * Function ircomm_check_modem_status (self)
1068  *
1069  *    Check for any changes in the DCE's line settings. This function should
1070  *    be called whenever the dce parameter settings changes, to update the
1071  *    flow control settings and other things
1072  */
ircomm_tty_check_modem_status(struct ircomm_tty_cb * self)1073 void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
1074 {
1075 	struct tty_struct *tty;
1076 	int status;
1077 
1078 	IRDA_DEBUG(0, "%s()\n", __func__ );
1079 
1080 	IRDA_ASSERT(self != NULL, return;);
1081 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1082 
1083 	tty = self->tty;
1084 
1085 	status = self->settings.dce;
1086 
1087 	if (status & IRCOMM_DCE_DELTA_ANY) {
1088 		/*wake_up_interruptible(&self->delta_msr_wait);*/
1089 	}
1090 	if ((self->flags & ASYNC_CHECK_CD) && (status & IRCOMM_DELTA_CD)) {
1091 		IRDA_DEBUG(2,
1092 			   "%s(), ircomm%d CD now %s...\n", __func__ , self->line,
1093 			   (status & IRCOMM_CD) ? "on" : "off");
1094 
1095 		if (status & IRCOMM_CD) {
1096 			wake_up_interruptible(&self->open_wait);
1097 		} else {
1098 			IRDA_DEBUG(2,
1099 				   "%s(), Doing serial hangup..\n", __func__ );
1100 			if (tty)
1101 				tty_hangup(tty);
1102 
1103 			/* Hangup will remote the tty, so better break out */
1104 			return;
1105 		}
1106 	}
1107 	if (self->flags & ASYNC_CTS_FLOW) {
1108 		if (tty->hw_stopped) {
1109 			if (status & IRCOMM_CTS) {
1110 				IRDA_DEBUG(2,
1111 					   "%s(), CTS tx start...\n", __func__ );
1112 				tty->hw_stopped = 0;
1113 
1114 				/* Wake up processes blocked on open */
1115 				wake_up_interruptible(&self->open_wait);
1116 
1117 				schedule_work(&self->tqueue);
1118 				return;
1119 			}
1120 		} else {
1121 			if (!(status & IRCOMM_CTS)) {
1122 				IRDA_DEBUG(2,
1123 					   "%s(), CTS tx stop...\n", __func__ );
1124 				tty->hw_stopped = 1;
1125 			}
1126 		}
1127 	}
1128 }
1129 
1130 /*
1131  * Function ircomm_tty_data_indication (instance, sap, skb)
1132  *
1133  *    Handle incoming data, and deliver it to the line discipline
1134  *
1135  */
ircomm_tty_data_indication(void * instance,void * sap,struct sk_buff * skb)1136 static int ircomm_tty_data_indication(void *instance, void *sap,
1137 				      struct sk_buff *skb)
1138 {
1139 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1140 	struct tty_ldisc *ld;
1141 
1142 	IRDA_DEBUG(2, "%s()\n", __func__ );
1143 
1144 	IRDA_ASSERT(self != NULL, return -1;);
1145 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1146 	IRDA_ASSERT(skb != NULL, return -1;);
1147 
1148 	if (!self->tty) {
1149 		IRDA_DEBUG(0, "%s(), no tty!\n", __func__ );
1150 		return 0;
1151 	}
1152 
1153 	/*
1154 	 * If we receive data when hardware is stopped then something is wrong.
1155 	 * We try to poll the peers line settings to check if we are up todate.
1156 	 * Devices like WinCE can do this, and since they don't send any
1157 	 * params, we can just as well declare the hardware for running.
1158 	 */
1159 	if (self->tty->hw_stopped && (self->flow == FLOW_START)) {
1160 		IRDA_DEBUG(0, "%s(), polling for line settings!\n", __func__ );
1161 		ircomm_param_request(self, IRCOMM_POLL, TRUE);
1162 
1163 		/* We can just as well declare the hardware for running */
1164 		ircomm_tty_send_initial_parameters(self);
1165 		ircomm_tty_link_established(self);
1166 	}
1167 
1168 	/*
1169 	 * Just give it over to the line discipline. There is no need to
1170 	 * involve the flip buffers, since we are not running in an interrupt
1171 	 * handler
1172 	 */
1173 
1174 	ld = tty_ldisc_ref(self->tty);
1175 	if (ld)
1176 		ld->ops->receive_buf(self->tty, skb->data, NULL, skb->len);
1177 	tty_ldisc_deref(ld);
1178 
1179 	/* No need to kfree_skb - see ircomm_ttp_data_indication() */
1180 
1181 	return 0;
1182 }
1183 
1184 /*
1185  * Function ircomm_tty_control_indication (instance, sap, skb)
1186  *
1187  *    Parse all incoming parameters (easy!)
1188  *
1189  */
ircomm_tty_control_indication(void * instance,void * sap,struct sk_buff * skb)1190 static int ircomm_tty_control_indication(void *instance, void *sap,
1191 					 struct sk_buff *skb)
1192 {
1193 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1194 	int clen;
1195 
1196 	IRDA_DEBUG(4, "%s()\n", __func__ );
1197 
1198 	IRDA_ASSERT(self != NULL, return -1;);
1199 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1200 	IRDA_ASSERT(skb != NULL, return -1;);
1201 
1202 	clen = skb->data[0];
1203 
1204 	irda_param_extract_all(self, skb->data+1, IRDA_MIN(skb->len-1, clen),
1205 			       &ircomm_param_info);
1206 
1207 	/* No need to kfree_skb - see ircomm_control_indication() */
1208 
1209 	return 0;
1210 }
1211 
1212 /*
1213  * Function ircomm_tty_flow_indication (instance, sap, cmd)
1214  *
1215  *    This function is called by IrTTP when it wants us to slow down the
1216  *    transmission of data. We just mark the hardware as stopped, and wait
1217  *    for IrTTP to notify us that things are OK again.
1218  */
ircomm_tty_flow_indication(void * instance,void * sap,LOCAL_FLOW cmd)1219 static void ircomm_tty_flow_indication(void *instance, void *sap,
1220 				       LOCAL_FLOW cmd)
1221 {
1222 	struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1223 	struct tty_struct *tty;
1224 
1225 	IRDA_ASSERT(self != NULL, return;);
1226 	IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1227 
1228 	tty = self->tty;
1229 
1230 	switch (cmd) {
1231 	case FLOW_START:
1232 		IRDA_DEBUG(2, "%s(), hw start!\n", __func__ );
1233 		tty->hw_stopped = 0;
1234 
1235 		/* ircomm_tty_do_softint will take care of the rest */
1236 		schedule_work(&self->tqueue);
1237 		break;
1238 	default:  /* If we get here, something is very wrong, better stop */
1239 	case FLOW_STOP:
1240 		IRDA_DEBUG(2, "%s(), hw stopped!\n", __func__ );
1241 		tty->hw_stopped = 1;
1242 		break;
1243 	}
1244 	self->flow = cmd;
1245 }
1246 
1247 #ifdef CONFIG_PROC_FS
ircomm_tty_line_info(struct ircomm_tty_cb * self,char * buf)1248 static int ircomm_tty_line_info(struct ircomm_tty_cb *self, char *buf)
1249 {
1250 	int  ret=0;
1251 
1252 	ret += sprintf(buf+ret, "State: %s\n", ircomm_tty_state[self->state]);
1253 
1254 	ret += sprintf(buf+ret, "Service type: ");
1255 	if (self->service_type & IRCOMM_9_WIRE)
1256 		ret += sprintf(buf+ret, "9_WIRE");
1257 	else if (self->service_type & IRCOMM_3_WIRE)
1258 		ret += sprintf(buf+ret, "3_WIRE");
1259 	else if (self->service_type & IRCOMM_3_WIRE_RAW)
1260 		ret += sprintf(buf+ret, "3_WIRE_RAW");
1261 	else
1262 		ret += sprintf(buf+ret, "No common service type!\n");
1263 	ret += sprintf(buf+ret, "\n");
1264 
1265 	ret += sprintf(buf+ret, "Port name: %s\n", self->settings.port_name);
1266 
1267 	ret += sprintf(buf+ret, "DTE status: ");
1268 	if (self->settings.dte & IRCOMM_RTS)
1269 		ret += sprintf(buf+ret, "RTS|");
1270 	if (self->settings.dte & IRCOMM_DTR)
1271 		ret += sprintf(buf+ret, "DTR|");
1272 	if (self->settings.dte)
1273 		ret--; /* remove the last | */
1274 	ret += sprintf(buf+ret, "\n");
1275 
1276 	ret += sprintf(buf+ret, "DCE status: ");
1277 	if (self->settings.dce & IRCOMM_CTS)
1278 		ret += sprintf(buf+ret, "CTS|");
1279 	if (self->settings.dce & IRCOMM_DSR)
1280 		ret += sprintf(buf+ret, "DSR|");
1281 	if (self->settings.dce & IRCOMM_CD)
1282 		ret += sprintf(buf+ret, "CD|");
1283 	if (self->settings.dce & IRCOMM_RI)
1284 		ret += sprintf(buf+ret, "RI|");
1285 	if (self->settings.dce)
1286 		ret--; /* remove the last | */
1287 	ret += sprintf(buf+ret, "\n");
1288 
1289 	ret += sprintf(buf+ret, "Configuration: ");
1290 	if (!self->settings.null_modem)
1291 		ret += sprintf(buf+ret, "DTE <-> DCE\n");
1292 	else
1293 		ret += sprintf(buf+ret,
1294 			       "DTE <-> DTE (null modem emulation)\n");
1295 
1296 	ret += sprintf(buf+ret, "Data rate: %d\n", self->settings.data_rate);
1297 
1298 	ret += sprintf(buf+ret, "Flow control: ");
1299 	if (self->settings.flow_control & IRCOMM_XON_XOFF_IN)
1300 		ret += sprintf(buf+ret, "XON_XOFF_IN|");
1301 	if (self->settings.flow_control & IRCOMM_XON_XOFF_OUT)
1302 		ret += sprintf(buf+ret, "XON_XOFF_OUT|");
1303 	if (self->settings.flow_control & IRCOMM_RTS_CTS_IN)
1304 		ret += sprintf(buf+ret, "RTS_CTS_IN|");
1305 	if (self->settings.flow_control & IRCOMM_RTS_CTS_OUT)
1306 		ret += sprintf(buf+ret, "RTS_CTS_OUT|");
1307 	if (self->settings.flow_control & IRCOMM_DSR_DTR_IN)
1308 		ret += sprintf(buf+ret, "DSR_DTR_IN|");
1309 	if (self->settings.flow_control & IRCOMM_DSR_DTR_OUT)
1310 		ret += sprintf(buf+ret, "DSR_DTR_OUT|");
1311 	if (self->settings.flow_control & IRCOMM_ENQ_ACK_IN)
1312 		ret += sprintf(buf+ret, "ENQ_ACK_IN|");
1313 	if (self->settings.flow_control & IRCOMM_ENQ_ACK_OUT)
1314 		ret += sprintf(buf+ret, "ENQ_ACK_OUT|");
1315 	if (self->settings.flow_control)
1316 		ret--; /* remove the last | */
1317 	ret += sprintf(buf+ret, "\n");
1318 
1319 	ret += sprintf(buf+ret, "Flags: ");
1320 	if (self->flags & ASYNC_CTS_FLOW)
1321 		ret += sprintf(buf+ret, "ASYNC_CTS_FLOW|");
1322 	if (self->flags & ASYNC_CHECK_CD)
1323 		ret += sprintf(buf+ret, "ASYNC_CHECK_CD|");
1324 	if (self->flags & ASYNC_INITIALIZED)
1325 		ret += sprintf(buf+ret, "ASYNC_INITIALIZED|");
1326 	if (self->flags & ASYNC_LOW_LATENCY)
1327 		ret += sprintf(buf+ret, "ASYNC_LOW_LATENCY|");
1328 	if (self->flags & ASYNC_CLOSING)
1329 		ret += sprintf(buf+ret, "ASYNC_CLOSING|");
1330 	if (self->flags & ASYNC_NORMAL_ACTIVE)
1331 		ret += sprintf(buf+ret, "ASYNC_NORMAL_ACTIVE|");
1332 	if (self->flags)
1333 		ret--; /* remove the last | */
1334 	ret += sprintf(buf+ret, "\n");
1335 
1336 	ret += sprintf(buf+ret, "Role: %s\n", self->client ?
1337 		       "client" : "server");
1338 	ret += sprintf(buf+ret, "Open count: %d\n", self->open_count);
1339 	ret += sprintf(buf+ret, "Max data size: %d\n", self->max_data_size);
1340 	ret += sprintf(buf+ret, "Max header size: %d\n", self->max_header_size);
1341 
1342 	if (self->tty)
1343 		ret += sprintf(buf+ret, "Hardware: %s\n",
1344 			       self->tty->hw_stopped ? "Stopped" : "Running");
1345 
1346 	ret += sprintf(buf+ret, "\n");
1347 	return ret;
1348 }
1349 
1350 
1351 /*
1352  * Function ircomm_tty_read_proc (buf, start, offset, len, eof, unused)
1353  *
1354  *
1355  *
1356  */
ircomm_tty_read_proc(char * buf,char ** start,off_t offset,int len,int * eof,void * unused)1357 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
1358 				int *eof, void *unused)
1359 {
1360 	struct ircomm_tty_cb *self;
1361 	int count = 0, l;
1362 	off_t begin = 0;
1363 	unsigned long flags;
1364 
1365 	spin_lock_irqsave(&ircomm_tty->hb_spinlock, flags);
1366 
1367 	self = (struct ircomm_tty_cb *) hashbin_get_first(ircomm_tty);
1368 	while ((self != NULL) && (count < 4000)) {
1369 		if (self->magic != IRCOMM_TTY_MAGIC)
1370 			break;
1371 
1372 		l = ircomm_tty_line_info(self, buf + count);
1373 		count += l;
1374 		if (count+begin > offset+len)
1375 			goto done;
1376 		if (count+begin < offset) {
1377 			begin += count;
1378 			count = 0;
1379 		}
1380 
1381 		self = (struct ircomm_tty_cb *) hashbin_get_next(ircomm_tty);
1382 	}
1383 	*eof = 1;
1384 done:
1385 	spin_unlock_irqrestore(&ircomm_tty->hb_spinlock, flags);
1386 
1387 	if (offset >= count+begin)
1388 		return 0;
1389 	*start = buf + (offset-begin);
1390 	return ((len < begin+count-offset) ? len : begin+count-offset);
1391 }
1392 #endif /* CONFIG_PROC_FS */
1393 
1394 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
1395 MODULE_DESCRIPTION("IrCOMM serial TTY driver");
1396 MODULE_LICENSE("GPL");
1397 MODULE_ALIAS_CHARDEV_MAJOR(IRCOMM_TTY_MAJOR);
1398 
1399 module_init(ircomm_tty_init);
1400 module_exit(ircomm_tty_cleanup);
1401