xref: /openbmc/linux/net/bluetooth/rfcomm/tty.c (revision f7777dcc)
1 /*
2    RFCOMM implementation for Linux Bluetooth stack (BlueZ).
3    Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
4    Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License version 2 as
8    published by the Free Software Foundation;
9 
10    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 
19    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21    SOFTWARE IS DISCLAIMED.
22 */
23 
24 /*
25  * RFCOMM TTY.
26  */
27 
28 #include <linux/module.h>
29 
30 #include <linux/tty.h>
31 #include <linux/tty_driver.h>
32 #include <linux/tty_flip.h>
33 
34 #include <net/bluetooth/bluetooth.h>
35 #include <net/bluetooth/hci_core.h>
36 #include <net/bluetooth/rfcomm.h>
37 
38 #define RFCOMM_TTY_MAGIC 0x6d02		/* magic number for rfcomm struct */
39 #define RFCOMM_TTY_PORTS RFCOMM_MAX_DEV	/* whole lotta rfcomm devices */
40 #define RFCOMM_TTY_MAJOR 216		/* device node major id of the usb/bluetooth.c driver */
41 #define RFCOMM_TTY_MINOR 0
42 
43 static struct tty_driver *rfcomm_tty_driver;
44 
45 struct rfcomm_dev {
46 	struct tty_port		port;
47 	struct list_head	list;
48 
49 	char			name[12];
50 	int			id;
51 	unsigned long		flags;
52 	int			err;
53 
54 	bdaddr_t		src;
55 	bdaddr_t		dst;
56 	u8			channel;
57 
58 	uint			modem_status;
59 
60 	struct rfcomm_dlc	*dlc;
61 
62 	struct device		*tty_dev;
63 
64 	atomic_t		wmem_alloc;
65 
66 	struct sk_buff_head	pending;
67 };
68 
69 static LIST_HEAD(rfcomm_dev_list);
70 static DEFINE_SPINLOCK(rfcomm_dev_lock);
71 
72 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb);
73 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err);
74 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
75 
76 /* ---- Device functions ---- */
77 
78 static void rfcomm_dev_destruct(struct tty_port *port)
79 {
80 	struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
81 	struct rfcomm_dlc *dlc = dev->dlc;
82 
83 	BT_DBG("dev %p dlc %p", dev, dlc);
84 
85 	spin_lock(&rfcomm_dev_lock);
86 	list_del(&dev->list);
87 	spin_unlock(&rfcomm_dev_lock);
88 
89 	rfcomm_dlc_lock(dlc);
90 	/* Detach DLC if it's owned by this dev */
91 	if (dlc->owner == dev)
92 		dlc->owner = NULL;
93 	rfcomm_dlc_unlock(dlc);
94 
95 	rfcomm_dlc_put(dlc);
96 
97 	tty_unregister_device(rfcomm_tty_driver, dev->id);
98 
99 	kfree(dev);
100 
101 	/* It's safe to call module_put() here because socket still
102 	   holds reference to this module. */
103 	module_put(THIS_MODULE);
104 }
105 
106 /* device-specific initialization: open the dlc */
107 static int rfcomm_dev_activate(struct tty_port *port, struct tty_struct *tty)
108 {
109 	struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
110 
111 	return rfcomm_dlc_open(dev->dlc, &dev->src, &dev->dst, dev->channel);
112 }
113 
114 /* we block the open until the dlc->state becomes BT_CONNECTED */
115 static int rfcomm_dev_carrier_raised(struct tty_port *port)
116 {
117 	struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
118 
119 	return (dev->dlc->state == BT_CONNECTED);
120 }
121 
122 /* device-specific cleanup: close the dlc */
123 static void rfcomm_dev_shutdown(struct tty_port *port)
124 {
125 	struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
126 
127 	if (dev->tty_dev->parent)
128 		device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
129 
130 	/* close the dlc */
131 	rfcomm_dlc_close(dev->dlc, 0);
132 }
133 
134 static const struct tty_port_operations rfcomm_port_ops = {
135 	.destruct = rfcomm_dev_destruct,
136 	.activate = rfcomm_dev_activate,
137 	.shutdown = rfcomm_dev_shutdown,
138 	.carrier_raised = rfcomm_dev_carrier_raised,
139 };
140 
141 static struct rfcomm_dev *__rfcomm_dev_get(int id)
142 {
143 	struct rfcomm_dev *dev;
144 
145 	list_for_each_entry(dev, &rfcomm_dev_list, list)
146 		if (dev->id == id)
147 			return dev;
148 
149 	return NULL;
150 }
151 
152 static struct rfcomm_dev *rfcomm_dev_get(int id)
153 {
154 	struct rfcomm_dev *dev;
155 
156 	spin_lock(&rfcomm_dev_lock);
157 
158 	dev = __rfcomm_dev_get(id);
159 
160 	if (dev) {
161 		if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
162 			dev = NULL;
163 		else
164 			tty_port_get(&dev->port);
165 	}
166 
167 	spin_unlock(&rfcomm_dev_lock);
168 
169 	return dev;
170 }
171 
172 static struct device *rfcomm_get_device(struct rfcomm_dev *dev)
173 {
174 	struct hci_dev *hdev;
175 	struct hci_conn *conn;
176 
177 	hdev = hci_get_route(&dev->dst, &dev->src);
178 	if (!hdev)
179 		return NULL;
180 
181 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &dev->dst);
182 
183 	hci_dev_put(hdev);
184 
185 	return conn ? &conn->dev : NULL;
186 }
187 
188 static ssize_t show_address(struct device *tty_dev, struct device_attribute *attr, char *buf)
189 {
190 	struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
191 	return sprintf(buf, "%pMR\n", &dev->dst);
192 }
193 
194 static ssize_t show_channel(struct device *tty_dev, struct device_attribute *attr, char *buf)
195 {
196 	struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
197 	return sprintf(buf, "%d\n", dev->channel);
198 }
199 
200 static DEVICE_ATTR(address, S_IRUGO, show_address, NULL);
201 static DEVICE_ATTR(channel, S_IRUGO, show_channel, NULL);
202 
203 static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
204 {
205 	struct rfcomm_dev *dev, *entry;
206 	struct list_head *head = &rfcomm_dev_list;
207 	int err = 0;
208 
209 	BT_DBG("id %d channel %d", req->dev_id, req->channel);
210 
211 	dev = kzalloc(sizeof(struct rfcomm_dev), GFP_KERNEL);
212 	if (!dev)
213 		return -ENOMEM;
214 
215 	spin_lock(&rfcomm_dev_lock);
216 
217 	if (req->dev_id < 0) {
218 		dev->id = 0;
219 
220 		list_for_each_entry(entry, &rfcomm_dev_list, list) {
221 			if (entry->id != dev->id)
222 				break;
223 
224 			dev->id++;
225 			head = &entry->list;
226 		}
227 	} else {
228 		dev->id = req->dev_id;
229 
230 		list_for_each_entry(entry, &rfcomm_dev_list, list) {
231 			if (entry->id == dev->id) {
232 				err = -EADDRINUSE;
233 				goto out;
234 			}
235 
236 			if (entry->id > dev->id - 1)
237 				break;
238 
239 			head = &entry->list;
240 		}
241 	}
242 
243 	if ((dev->id < 0) || (dev->id > RFCOMM_MAX_DEV - 1)) {
244 		err = -ENFILE;
245 		goto out;
246 	}
247 
248 	sprintf(dev->name, "rfcomm%d", dev->id);
249 
250 	list_add(&dev->list, head);
251 
252 	bacpy(&dev->src, &req->src);
253 	bacpy(&dev->dst, &req->dst);
254 	dev->channel = req->channel;
255 
256 	dev->flags = req->flags &
257 		((1 << RFCOMM_RELEASE_ONHUP) | (1 << RFCOMM_REUSE_DLC));
258 
259 	tty_port_init(&dev->port);
260 	dev->port.ops = &rfcomm_port_ops;
261 
262 	skb_queue_head_init(&dev->pending);
263 
264 	rfcomm_dlc_lock(dlc);
265 
266 	if (req->flags & (1 << RFCOMM_REUSE_DLC)) {
267 		struct sock *sk = dlc->owner;
268 		struct sk_buff *skb;
269 
270 		BUG_ON(!sk);
271 
272 		rfcomm_dlc_throttle(dlc);
273 
274 		while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
275 			skb_orphan(skb);
276 			skb_queue_tail(&dev->pending, skb);
277 			atomic_sub(skb->len, &sk->sk_rmem_alloc);
278 		}
279 	}
280 
281 	dlc->data_ready   = rfcomm_dev_data_ready;
282 	dlc->state_change = rfcomm_dev_state_change;
283 	dlc->modem_status = rfcomm_dev_modem_status;
284 
285 	dlc->owner = dev;
286 	dev->dlc   = dlc;
287 
288 	rfcomm_dev_modem_status(dlc, dlc->remote_v24_sig);
289 
290 	rfcomm_dlc_unlock(dlc);
291 
292 	/* It's safe to call __module_get() here because socket already
293 	   holds reference to this module. */
294 	__module_get(THIS_MODULE);
295 
296 out:
297 	spin_unlock(&rfcomm_dev_lock);
298 
299 	if (err < 0)
300 		goto free;
301 
302 	dev->tty_dev = tty_port_register_device(&dev->port, rfcomm_tty_driver,
303 			dev->id, NULL);
304 	if (IS_ERR(dev->tty_dev)) {
305 		err = PTR_ERR(dev->tty_dev);
306 		spin_lock(&rfcomm_dev_lock);
307 		list_del(&dev->list);
308 		spin_unlock(&rfcomm_dev_lock);
309 		goto free;
310 	}
311 
312 	dev_set_drvdata(dev->tty_dev, dev);
313 
314 	if (device_create_file(dev->tty_dev, &dev_attr_address) < 0)
315 		BT_ERR("Failed to create address attribute");
316 
317 	if (device_create_file(dev->tty_dev, &dev_attr_channel) < 0)
318 		BT_ERR("Failed to create channel attribute");
319 
320 	return dev->id;
321 
322 free:
323 	kfree(dev);
324 	return err;
325 }
326 
327 /* ---- Send buffer ---- */
328 static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
329 {
330 	/* We can't let it be zero, because we don't get a callback
331 	   when tx_credits becomes nonzero, hence we'd never wake up */
332 	return dlc->mtu * (dlc->tx_credits?:1);
333 }
334 
335 static void rfcomm_wfree(struct sk_buff *skb)
336 {
337 	struct rfcomm_dev *dev = (void *) skb->sk;
338 	atomic_sub(skb->truesize, &dev->wmem_alloc);
339 	if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags))
340 		tty_port_tty_wakeup(&dev->port);
341 	tty_port_put(&dev->port);
342 }
343 
344 static void rfcomm_set_owner_w(struct sk_buff *skb, struct rfcomm_dev *dev)
345 {
346 	tty_port_get(&dev->port);
347 	atomic_add(skb->truesize, &dev->wmem_alloc);
348 	skb->sk = (void *) dev;
349 	skb->destructor = rfcomm_wfree;
350 }
351 
352 static struct sk_buff *rfcomm_wmalloc(struct rfcomm_dev *dev, unsigned long size, gfp_t priority)
353 {
354 	if (atomic_read(&dev->wmem_alloc) < rfcomm_room(dev->dlc)) {
355 		struct sk_buff *skb = alloc_skb(size, priority);
356 		if (skb) {
357 			rfcomm_set_owner_w(skb, dev);
358 			return skb;
359 		}
360 	}
361 	return NULL;
362 }
363 
364 /* ---- Device IOCTLs ---- */
365 
366 #define NOCAP_FLAGS ((1 << RFCOMM_REUSE_DLC) | (1 << RFCOMM_RELEASE_ONHUP))
367 
368 static int rfcomm_create_dev(struct sock *sk, void __user *arg)
369 {
370 	struct rfcomm_dev_req req;
371 	struct rfcomm_dlc *dlc;
372 	int id;
373 
374 	if (copy_from_user(&req, arg, sizeof(req)))
375 		return -EFAULT;
376 
377 	BT_DBG("sk %p dev_id %d flags 0x%x", sk, req.dev_id, req.flags);
378 
379 	if (req.flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN))
380 		return -EPERM;
381 
382 	if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
383 		/* Socket must be connected */
384 		if (sk->sk_state != BT_CONNECTED)
385 			return -EBADFD;
386 
387 		dlc = rfcomm_pi(sk)->dlc;
388 		rfcomm_dlc_hold(dlc);
389 	} else {
390 		dlc = rfcomm_dlc_alloc(GFP_KERNEL);
391 		if (!dlc)
392 			return -ENOMEM;
393 	}
394 
395 	id = rfcomm_dev_add(&req, dlc);
396 	if (id < 0) {
397 		rfcomm_dlc_put(dlc);
398 		return id;
399 	}
400 
401 	if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
402 		/* DLC is now used by device.
403 		 * Socket must be disconnected */
404 		sk->sk_state = BT_CLOSED;
405 	}
406 
407 	return id;
408 }
409 
410 static int rfcomm_release_dev(void __user *arg)
411 {
412 	struct rfcomm_dev_req req;
413 	struct rfcomm_dev *dev;
414 	struct tty_struct *tty;
415 
416 	if (copy_from_user(&req, arg, sizeof(req)))
417 		return -EFAULT;
418 
419 	BT_DBG("dev_id %d flags 0x%x", req.dev_id, req.flags);
420 
421 	dev = rfcomm_dev_get(req.dev_id);
422 	if (!dev)
423 		return -ENODEV;
424 
425 	if (dev->flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN)) {
426 		tty_port_put(&dev->port);
427 		return -EPERM;
428 	}
429 
430 	if (req.flags & (1 << RFCOMM_HANGUP_NOW))
431 		rfcomm_dlc_close(dev->dlc, 0);
432 
433 	/* Shut down TTY synchronously before freeing rfcomm_dev */
434 	tty = tty_port_tty_get(&dev->port);
435 	if (tty) {
436 		tty_vhangup(tty);
437 		tty_kref_put(tty);
438 	}
439 
440 	if (!test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags))
441 		tty_port_put(&dev->port);
442 
443 	tty_port_put(&dev->port);
444 	return 0;
445 }
446 
447 static int rfcomm_get_dev_list(void __user *arg)
448 {
449 	struct rfcomm_dev *dev;
450 	struct rfcomm_dev_list_req *dl;
451 	struct rfcomm_dev_info *di;
452 	int n = 0, size, err;
453 	u16 dev_num;
454 
455 	BT_DBG("");
456 
457 	if (get_user(dev_num, (u16 __user *) arg))
458 		return -EFAULT;
459 
460 	if (!dev_num || dev_num > (PAGE_SIZE * 4) / sizeof(*di))
461 		return -EINVAL;
462 
463 	size = sizeof(*dl) + dev_num * sizeof(*di);
464 
465 	dl = kzalloc(size, GFP_KERNEL);
466 	if (!dl)
467 		return -ENOMEM;
468 
469 	di = dl->dev_info;
470 
471 	spin_lock(&rfcomm_dev_lock);
472 
473 	list_for_each_entry(dev, &rfcomm_dev_list, list) {
474 		if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
475 			continue;
476 		(di + n)->id      = dev->id;
477 		(di + n)->flags   = dev->flags;
478 		(di + n)->state   = dev->dlc->state;
479 		(di + n)->channel = dev->channel;
480 		bacpy(&(di + n)->src, &dev->src);
481 		bacpy(&(di + n)->dst, &dev->dst);
482 		if (++n >= dev_num)
483 			break;
484 	}
485 
486 	spin_unlock(&rfcomm_dev_lock);
487 
488 	dl->dev_num = n;
489 	size = sizeof(*dl) + n * sizeof(*di);
490 
491 	err = copy_to_user(arg, dl, size);
492 	kfree(dl);
493 
494 	return err ? -EFAULT : 0;
495 }
496 
497 static int rfcomm_get_dev_info(void __user *arg)
498 {
499 	struct rfcomm_dev *dev;
500 	struct rfcomm_dev_info di;
501 	int err = 0;
502 
503 	BT_DBG("");
504 
505 	if (copy_from_user(&di, arg, sizeof(di)))
506 		return -EFAULT;
507 
508 	dev = rfcomm_dev_get(di.id);
509 	if (!dev)
510 		return -ENODEV;
511 
512 	di.flags   = dev->flags;
513 	di.channel = dev->channel;
514 	di.state   = dev->dlc->state;
515 	bacpy(&di.src, &dev->src);
516 	bacpy(&di.dst, &dev->dst);
517 
518 	if (copy_to_user(arg, &di, sizeof(di)))
519 		err = -EFAULT;
520 
521 	tty_port_put(&dev->port);
522 	return err;
523 }
524 
525 int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
526 {
527 	BT_DBG("cmd %d arg %p", cmd, arg);
528 
529 	switch (cmd) {
530 	case RFCOMMCREATEDEV:
531 		return rfcomm_create_dev(sk, arg);
532 
533 	case RFCOMMRELEASEDEV:
534 		return rfcomm_release_dev(arg);
535 
536 	case RFCOMMGETDEVLIST:
537 		return rfcomm_get_dev_list(arg);
538 
539 	case RFCOMMGETDEVINFO:
540 		return rfcomm_get_dev_info(arg);
541 	}
542 
543 	return -EINVAL;
544 }
545 
546 /* ---- DLC callbacks ---- */
547 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
548 {
549 	struct rfcomm_dev *dev = dlc->owner;
550 
551 	if (!dev) {
552 		kfree_skb(skb);
553 		return;
554 	}
555 
556 	if (!skb_queue_empty(&dev->pending)) {
557 		skb_queue_tail(&dev->pending, skb);
558 		return;
559 	}
560 
561 	BT_DBG("dlc %p len %d", dlc, skb->len);
562 
563 	tty_insert_flip_string(&dev->port, skb->data, skb->len);
564 	tty_flip_buffer_push(&dev->port);
565 
566 	kfree_skb(skb);
567 }
568 
569 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
570 {
571 	struct rfcomm_dev *dev = dlc->owner;
572 	if (!dev)
573 		return;
574 
575 	BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
576 
577 	dev->err = err;
578 	if (dlc->state == BT_CONNECTED) {
579 		device_move(dev->tty_dev, rfcomm_get_device(dev),
580 			    DPM_ORDER_DEV_AFTER_PARENT);
581 
582 		wake_up_interruptible(&dev->port.open_wait);
583 	} else if (dlc->state == BT_CLOSED)
584 		tty_port_tty_hangup(&dev->port, false);
585 }
586 
587 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
588 {
589 	struct rfcomm_dev *dev = dlc->owner;
590 	if (!dev)
591 		return;
592 
593 	BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
594 
595 	if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV))
596 		tty_port_tty_hangup(&dev->port, true);
597 
598 	dev->modem_status =
599 		((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
600 		((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) |
601 		((v24_sig & RFCOMM_V24_IC)  ? TIOCM_RI : 0) |
602 		((v24_sig & RFCOMM_V24_DV)  ? TIOCM_CD : 0);
603 }
604 
605 /* ---- TTY functions ---- */
606 static void rfcomm_tty_copy_pending(struct rfcomm_dev *dev)
607 {
608 	struct sk_buff *skb;
609 	int inserted = 0;
610 
611 	BT_DBG("dev %p", dev);
612 
613 	rfcomm_dlc_lock(dev->dlc);
614 
615 	while ((skb = skb_dequeue(&dev->pending))) {
616 		inserted += tty_insert_flip_string(&dev->port, skb->data,
617 				skb->len);
618 		kfree_skb(skb);
619 	}
620 
621 	rfcomm_dlc_unlock(dev->dlc);
622 
623 	if (inserted > 0)
624 		tty_flip_buffer_push(&dev->port);
625 }
626 
627 /* do the reverse of install, clearing the tty fields and releasing the
628  * reference to tty_port
629  */
630 static void rfcomm_tty_cleanup(struct tty_struct *tty)
631 {
632 	struct rfcomm_dev *dev = tty->driver_data;
633 
634 	clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
635 
636 	rfcomm_dlc_lock(dev->dlc);
637 	tty->driver_data = NULL;
638 	rfcomm_dlc_unlock(dev->dlc);
639 
640 	/*
641 	 * purge the dlc->tx_queue to avoid circular dependencies
642 	 * between dev and dlc
643 	 */
644 	skb_queue_purge(&dev->dlc->tx_queue);
645 
646 	tty_port_put(&dev->port);
647 }
648 
649 /* we acquire the tty_port reference since it's here the tty is first used
650  * by setting the termios. We also populate the driver_data field and install
651  * the tty port
652  */
653 static int rfcomm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
654 {
655 	struct rfcomm_dev *dev;
656 	struct rfcomm_dlc *dlc;
657 	int err;
658 
659 	dev = rfcomm_dev_get(tty->index);
660 	if (!dev)
661 		return -ENODEV;
662 
663 	dlc = dev->dlc;
664 
665 	/* Attach TTY and open DLC */
666 	rfcomm_dlc_lock(dlc);
667 	tty->driver_data = dev;
668 	rfcomm_dlc_unlock(dlc);
669 	set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
670 
671 	/* install the tty_port */
672 	err = tty_port_install(&dev->port, driver, tty);
673 	if (err)
674 		rfcomm_tty_cleanup(tty);
675 
676 	return err;
677 }
678 
679 static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
680 {
681 	struct rfcomm_dev *dev = tty->driver_data;
682 	int err;
683 
684 	BT_DBG("tty %p id %d", tty, tty->index);
685 
686 	BT_DBG("dev %p dst %pMR channel %d opened %d", dev, &dev->dst,
687 	       dev->channel, dev->port.count);
688 
689 	err = tty_port_open(&dev->port, tty, filp);
690 	if (err)
691 		return err;
692 
693 	/*
694 	 * FIXME: rfcomm should use proper flow control for
695 	 * received data. This hack will be unnecessary and can
696 	 * be removed when that's implemented
697 	 */
698 	rfcomm_tty_copy_pending(dev);
699 
700 	rfcomm_dlc_unthrottle(dev->dlc);
701 
702 	return 0;
703 }
704 
705 static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
706 {
707 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
708 
709 	BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc,
710 						dev->port.count);
711 
712 	tty_port_close(&dev->port, tty, filp);
713 }
714 
715 static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
716 {
717 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
718 	struct rfcomm_dlc *dlc = dev->dlc;
719 	struct sk_buff *skb;
720 	int err = 0, sent = 0, size;
721 
722 	BT_DBG("tty %p count %d", tty, count);
723 
724 	while (count) {
725 		size = min_t(uint, count, dlc->mtu);
726 
727 		skb = rfcomm_wmalloc(dev, size + RFCOMM_SKB_RESERVE, GFP_ATOMIC);
728 
729 		if (!skb)
730 			break;
731 
732 		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
733 
734 		memcpy(skb_put(skb, size), buf + sent, size);
735 
736 		err = rfcomm_dlc_send(dlc, skb);
737 		if (err < 0) {
738 			kfree_skb(skb);
739 			break;
740 		}
741 
742 		sent  += size;
743 		count -= size;
744 	}
745 
746 	return sent ? sent : err;
747 }
748 
749 static int rfcomm_tty_write_room(struct tty_struct *tty)
750 {
751 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
752 	int room;
753 
754 	BT_DBG("tty %p", tty);
755 
756 	if (!dev || !dev->dlc)
757 		return 0;
758 
759 	room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
760 	if (room < 0)
761 		room = 0;
762 
763 	return room;
764 }
765 
766 static int rfcomm_tty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
767 {
768 	BT_DBG("tty %p cmd 0x%02x", tty, cmd);
769 
770 	switch (cmd) {
771 	case TCGETS:
772 		BT_DBG("TCGETS is not supported");
773 		return -ENOIOCTLCMD;
774 
775 	case TCSETS:
776 		BT_DBG("TCSETS is not supported");
777 		return -ENOIOCTLCMD;
778 
779 	case TIOCMIWAIT:
780 		BT_DBG("TIOCMIWAIT");
781 		break;
782 
783 	case TIOCGSERIAL:
784 		BT_ERR("TIOCGSERIAL is not supported");
785 		return -ENOIOCTLCMD;
786 
787 	case TIOCSSERIAL:
788 		BT_ERR("TIOCSSERIAL is not supported");
789 		return -ENOIOCTLCMD;
790 
791 	case TIOCSERGSTRUCT:
792 		BT_ERR("TIOCSERGSTRUCT is not supported");
793 		return -ENOIOCTLCMD;
794 
795 	case TIOCSERGETLSR:
796 		BT_ERR("TIOCSERGETLSR is not supported");
797 		return -ENOIOCTLCMD;
798 
799 	case TIOCSERCONFIG:
800 		BT_ERR("TIOCSERCONFIG is not supported");
801 		return -ENOIOCTLCMD;
802 
803 	default:
804 		return -ENOIOCTLCMD;	/* ioctls which we must ignore */
805 
806 	}
807 
808 	return -ENOIOCTLCMD;
809 }
810 
811 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
812 {
813 	struct ktermios *new = &tty->termios;
814 	int old_baud_rate = tty_termios_baud_rate(old);
815 	int new_baud_rate = tty_termios_baud_rate(new);
816 
817 	u8 baud, data_bits, stop_bits, parity, x_on, x_off;
818 	u16 changes = 0;
819 
820 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
821 
822 	BT_DBG("tty %p termios %p", tty, old);
823 
824 	if (!dev || !dev->dlc || !dev->dlc->session)
825 		return;
826 
827 	/* Handle turning off CRTSCTS */
828 	if ((old->c_cflag & CRTSCTS) && !(new->c_cflag & CRTSCTS))
829 		BT_DBG("Turning off CRTSCTS unsupported");
830 
831 	/* Parity on/off and when on, odd/even */
832 	if (((old->c_cflag & PARENB) != (new->c_cflag & PARENB)) ||
833 			((old->c_cflag & PARODD) != (new->c_cflag & PARODD))) {
834 		changes |= RFCOMM_RPN_PM_PARITY;
835 		BT_DBG("Parity change detected.");
836 	}
837 
838 	/* Mark and space parity are not supported! */
839 	if (new->c_cflag & PARENB) {
840 		if (new->c_cflag & PARODD) {
841 			BT_DBG("Parity is ODD");
842 			parity = RFCOMM_RPN_PARITY_ODD;
843 		} else {
844 			BT_DBG("Parity is EVEN");
845 			parity = RFCOMM_RPN_PARITY_EVEN;
846 		}
847 	} else {
848 		BT_DBG("Parity is OFF");
849 		parity = RFCOMM_RPN_PARITY_NONE;
850 	}
851 
852 	/* Setting the x_on / x_off characters */
853 	if (old->c_cc[VSTOP] != new->c_cc[VSTOP]) {
854 		BT_DBG("XOFF custom");
855 		x_on = new->c_cc[VSTOP];
856 		changes |= RFCOMM_RPN_PM_XON;
857 	} else {
858 		BT_DBG("XOFF default");
859 		x_on = RFCOMM_RPN_XON_CHAR;
860 	}
861 
862 	if (old->c_cc[VSTART] != new->c_cc[VSTART]) {
863 		BT_DBG("XON custom");
864 		x_off = new->c_cc[VSTART];
865 		changes |= RFCOMM_RPN_PM_XOFF;
866 	} else {
867 		BT_DBG("XON default");
868 		x_off = RFCOMM_RPN_XOFF_CHAR;
869 	}
870 
871 	/* Handle setting of stop bits */
872 	if ((old->c_cflag & CSTOPB) != (new->c_cflag & CSTOPB))
873 		changes |= RFCOMM_RPN_PM_STOP;
874 
875 	/* POSIX does not support 1.5 stop bits and RFCOMM does not
876 	 * support 2 stop bits. So a request for 2 stop bits gets
877 	 * translated to 1.5 stop bits */
878 	if (new->c_cflag & CSTOPB)
879 		stop_bits = RFCOMM_RPN_STOP_15;
880 	else
881 		stop_bits = RFCOMM_RPN_STOP_1;
882 
883 	/* Handle number of data bits [5-8] */
884 	if ((old->c_cflag & CSIZE) != (new->c_cflag & CSIZE))
885 		changes |= RFCOMM_RPN_PM_DATA;
886 
887 	switch (new->c_cflag & CSIZE) {
888 	case CS5:
889 		data_bits = RFCOMM_RPN_DATA_5;
890 		break;
891 	case CS6:
892 		data_bits = RFCOMM_RPN_DATA_6;
893 		break;
894 	case CS7:
895 		data_bits = RFCOMM_RPN_DATA_7;
896 		break;
897 	case CS8:
898 		data_bits = RFCOMM_RPN_DATA_8;
899 		break;
900 	default:
901 		data_bits = RFCOMM_RPN_DATA_8;
902 		break;
903 	}
904 
905 	/* Handle baudrate settings */
906 	if (old_baud_rate != new_baud_rate)
907 		changes |= RFCOMM_RPN_PM_BITRATE;
908 
909 	switch (new_baud_rate) {
910 	case 2400:
911 		baud = RFCOMM_RPN_BR_2400;
912 		break;
913 	case 4800:
914 		baud = RFCOMM_RPN_BR_4800;
915 		break;
916 	case 7200:
917 		baud = RFCOMM_RPN_BR_7200;
918 		break;
919 	case 9600:
920 		baud = RFCOMM_RPN_BR_9600;
921 		break;
922 	case 19200:
923 		baud = RFCOMM_RPN_BR_19200;
924 		break;
925 	case 38400:
926 		baud = RFCOMM_RPN_BR_38400;
927 		break;
928 	case 57600:
929 		baud = RFCOMM_RPN_BR_57600;
930 		break;
931 	case 115200:
932 		baud = RFCOMM_RPN_BR_115200;
933 		break;
934 	case 230400:
935 		baud = RFCOMM_RPN_BR_230400;
936 		break;
937 	default:
938 		/* 9600 is standard accordinag to the RFCOMM specification */
939 		baud = RFCOMM_RPN_BR_9600;
940 		break;
941 
942 	}
943 
944 	if (changes)
945 		rfcomm_send_rpn(dev->dlc->session, 1, dev->dlc->dlci, baud,
946 				data_bits, stop_bits, parity,
947 				RFCOMM_RPN_FLOW_NONE, x_on, x_off, changes);
948 }
949 
950 static void rfcomm_tty_throttle(struct tty_struct *tty)
951 {
952 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
953 
954 	BT_DBG("tty %p dev %p", tty, dev);
955 
956 	rfcomm_dlc_throttle(dev->dlc);
957 }
958 
959 static void rfcomm_tty_unthrottle(struct tty_struct *tty)
960 {
961 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
962 
963 	BT_DBG("tty %p dev %p", tty, dev);
964 
965 	rfcomm_dlc_unthrottle(dev->dlc);
966 }
967 
968 static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
969 {
970 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
971 
972 	BT_DBG("tty %p dev %p", tty, dev);
973 
974 	if (!dev || !dev->dlc)
975 		return 0;
976 
977 	if (!skb_queue_empty(&dev->dlc->tx_queue))
978 		return dev->dlc->mtu;
979 
980 	return 0;
981 }
982 
983 static void rfcomm_tty_flush_buffer(struct tty_struct *tty)
984 {
985 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
986 
987 	BT_DBG("tty %p dev %p", tty, dev);
988 
989 	if (!dev || !dev->dlc)
990 		return;
991 
992 	skb_queue_purge(&dev->dlc->tx_queue);
993 	tty_wakeup(tty);
994 }
995 
996 static void rfcomm_tty_send_xchar(struct tty_struct *tty, char ch)
997 {
998 	BT_DBG("tty %p ch %c", tty, ch);
999 }
1000 
1001 static void rfcomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
1002 {
1003 	BT_DBG("tty %p timeout %d", tty, timeout);
1004 }
1005 
1006 static void rfcomm_tty_hangup(struct tty_struct *tty)
1007 {
1008 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1009 
1010 	BT_DBG("tty %p dev %p", tty, dev);
1011 
1012 	tty_port_hangup(&dev->port);
1013 
1014 	if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags) &&
1015 	    !test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags))
1016 		tty_port_put(&dev->port);
1017 }
1018 
1019 static int rfcomm_tty_tiocmget(struct tty_struct *tty)
1020 {
1021 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1022 
1023 	BT_DBG("tty %p dev %p", tty, dev);
1024 
1025 	return dev->modem_status;
1026 }
1027 
1028 static int rfcomm_tty_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear)
1029 {
1030 	struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1031 	struct rfcomm_dlc *dlc = dev->dlc;
1032 	u8 v24_sig;
1033 
1034 	BT_DBG("tty %p dev %p set 0x%02x clear 0x%02x", tty, dev, set, clear);
1035 
1036 	rfcomm_dlc_get_modem_status(dlc, &v24_sig);
1037 
1038 	if (set & TIOCM_DSR || set & TIOCM_DTR)
1039 		v24_sig |= RFCOMM_V24_RTC;
1040 	if (set & TIOCM_RTS || set & TIOCM_CTS)
1041 		v24_sig |= RFCOMM_V24_RTR;
1042 	if (set & TIOCM_RI)
1043 		v24_sig |= RFCOMM_V24_IC;
1044 	if (set & TIOCM_CD)
1045 		v24_sig |= RFCOMM_V24_DV;
1046 
1047 	if (clear & TIOCM_DSR || clear & TIOCM_DTR)
1048 		v24_sig &= ~RFCOMM_V24_RTC;
1049 	if (clear & TIOCM_RTS || clear & TIOCM_CTS)
1050 		v24_sig &= ~RFCOMM_V24_RTR;
1051 	if (clear & TIOCM_RI)
1052 		v24_sig &= ~RFCOMM_V24_IC;
1053 	if (clear & TIOCM_CD)
1054 		v24_sig &= ~RFCOMM_V24_DV;
1055 
1056 	rfcomm_dlc_set_modem_status(dlc, v24_sig);
1057 
1058 	return 0;
1059 }
1060 
1061 /* ---- TTY structure ---- */
1062 
1063 static const struct tty_operations rfcomm_ops = {
1064 	.open			= rfcomm_tty_open,
1065 	.close			= rfcomm_tty_close,
1066 	.write			= rfcomm_tty_write,
1067 	.write_room		= rfcomm_tty_write_room,
1068 	.chars_in_buffer	= rfcomm_tty_chars_in_buffer,
1069 	.flush_buffer		= rfcomm_tty_flush_buffer,
1070 	.ioctl			= rfcomm_tty_ioctl,
1071 	.throttle		= rfcomm_tty_throttle,
1072 	.unthrottle		= rfcomm_tty_unthrottle,
1073 	.set_termios		= rfcomm_tty_set_termios,
1074 	.send_xchar		= rfcomm_tty_send_xchar,
1075 	.hangup			= rfcomm_tty_hangup,
1076 	.wait_until_sent	= rfcomm_tty_wait_until_sent,
1077 	.tiocmget		= rfcomm_tty_tiocmget,
1078 	.tiocmset		= rfcomm_tty_tiocmset,
1079 	.install                = rfcomm_tty_install,
1080 	.cleanup                = rfcomm_tty_cleanup,
1081 };
1082 
1083 int __init rfcomm_init_ttys(void)
1084 {
1085 	int error;
1086 
1087 	rfcomm_tty_driver = alloc_tty_driver(RFCOMM_TTY_PORTS);
1088 	if (!rfcomm_tty_driver)
1089 		return -ENOMEM;
1090 
1091 	rfcomm_tty_driver->driver_name	= "rfcomm";
1092 	rfcomm_tty_driver->name		= "rfcomm";
1093 	rfcomm_tty_driver->major	= RFCOMM_TTY_MAJOR;
1094 	rfcomm_tty_driver->minor_start	= RFCOMM_TTY_MINOR;
1095 	rfcomm_tty_driver->type		= TTY_DRIVER_TYPE_SERIAL;
1096 	rfcomm_tty_driver->subtype	= SERIAL_TYPE_NORMAL;
1097 	rfcomm_tty_driver->flags	= TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1098 	rfcomm_tty_driver->init_termios	= tty_std_termios;
1099 	rfcomm_tty_driver->init_termios.c_cflag	= B9600 | CS8 | CREAD | HUPCL;
1100 	rfcomm_tty_driver->init_termios.c_lflag &= ~ICANON;
1101 	tty_set_operations(rfcomm_tty_driver, &rfcomm_ops);
1102 
1103 	error = tty_register_driver(rfcomm_tty_driver);
1104 	if (error) {
1105 		BT_ERR("Can't register RFCOMM TTY driver");
1106 		put_tty_driver(rfcomm_tty_driver);
1107 		return error;
1108 	}
1109 
1110 	BT_INFO("RFCOMM TTY layer initialized");
1111 
1112 	return 0;
1113 }
1114 
1115 void rfcomm_cleanup_ttys(void)
1116 {
1117 	tty_unregister_driver(rfcomm_tty_driver);
1118 	put_tty_driver(rfcomm_tty_driver);
1119 }
1120