xref: /linux/drivers/bluetooth/hci_ldisc.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  *
3  *  Bluetooth HCI UART driver
4  *
5  *  Copyright (C) 2000-2001  Qualcomm Incorporated
6  *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
7  *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
8  *
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or
13  *  (at your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License
21  *  along with this program; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23  *
24  */
25 
26 #include <linux/module.h>
27 
28 #include <linux/kernel.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/fcntl.h>
32 #include <linux/interrupt.h>
33 #include <linux/ptrace.h>
34 #include <linux/poll.h>
35 
36 #include <linux/slab.h>
37 #include <linux/tty.h>
38 #include <linux/errno.h>
39 #include <linux/string.h>
40 #include <linux/signal.h>
41 #include <linux/ioctl.h>
42 #include <linux/skbuff.h>
43 #include <linux/firmware.h>
44 
45 #include <net/bluetooth/bluetooth.h>
46 #include <net/bluetooth/hci_core.h>
47 
48 #include "btintel.h"
49 #include "btbcm.h"
50 #include "hci_uart.h"
51 
52 #define VERSION "2.3"
53 
54 static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
55 
56 int hci_uart_register_proto(const struct hci_uart_proto *p)
57 {
58 	if (p->id >= HCI_UART_MAX_PROTO)
59 		return -EINVAL;
60 
61 	if (hup[p->id])
62 		return -EEXIST;
63 
64 	hup[p->id] = p;
65 
66 	BT_INFO("HCI UART protocol %s registered", p->name);
67 
68 	return 0;
69 }
70 
71 int hci_uart_unregister_proto(const struct hci_uart_proto *p)
72 {
73 	if (p->id >= HCI_UART_MAX_PROTO)
74 		return -EINVAL;
75 
76 	if (!hup[p->id])
77 		return -EINVAL;
78 
79 	hup[p->id] = NULL;
80 
81 	return 0;
82 }
83 
84 static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
85 {
86 	if (id >= HCI_UART_MAX_PROTO)
87 		return NULL;
88 
89 	return hup[id];
90 }
91 
92 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
93 {
94 	struct hci_dev *hdev = hu->hdev;
95 
96 	/* Update HCI stat counters */
97 	switch (pkt_type) {
98 	case HCI_COMMAND_PKT:
99 		hdev->stat.cmd_tx++;
100 		break;
101 
102 	case HCI_ACLDATA_PKT:
103 		hdev->stat.acl_tx++;
104 		break;
105 
106 	case HCI_SCODATA_PKT:
107 		hdev->stat.sco_tx++;
108 		break;
109 	}
110 }
111 
112 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
113 {
114 	struct sk_buff *skb = hu->tx_skb;
115 
116 	if (!skb) {
117 		if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
118 			skb = hu->proto->dequeue(hu);
119 	} else {
120 		hu->tx_skb = NULL;
121 	}
122 
123 	return skb;
124 }
125 
126 int hci_uart_tx_wakeup(struct hci_uart *hu)
127 {
128 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
129 		return 0;
130 
131 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
132 		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
133 		return 0;
134 	}
135 
136 	BT_DBG("");
137 
138 	schedule_work(&hu->write_work);
139 
140 	return 0;
141 }
142 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
143 
144 static void hci_uart_write_work(struct work_struct *work)
145 {
146 	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
147 	struct tty_struct *tty = hu->tty;
148 	struct hci_dev *hdev = hu->hdev;
149 	struct sk_buff *skb;
150 
151 	/* REVISIT: should we cope with bad skbs or ->write() returning
152 	 * and error value ?
153 	 */
154 
155 restart:
156 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
157 
158 	while ((skb = hci_uart_dequeue(hu))) {
159 		int len;
160 
161 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
162 		len = tty->ops->write(tty, skb->data, skb->len);
163 		hdev->stat.byte_tx += len;
164 
165 		skb_pull(skb, len);
166 		if (skb->len) {
167 			hu->tx_skb = skb;
168 			break;
169 		}
170 
171 		hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
172 		kfree_skb(skb);
173 	}
174 
175 	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
176 		goto restart;
177 
178 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
179 }
180 
181 static void hci_uart_init_work(struct work_struct *work)
182 {
183 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
184 	int err;
185 	struct hci_dev *hdev;
186 
187 	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
188 		return;
189 
190 	err = hci_register_dev(hu->hdev);
191 	if (err < 0) {
192 		BT_ERR("Can't register HCI device");
193 		hdev = hu->hdev;
194 		hu->hdev = NULL;
195 		hci_free_dev(hdev);
196 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
197 		hu->proto->close(hu);
198 		return;
199 	}
200 
201 	set_bit(HCI_UART_REGISTERED, &hu->flags);
202 }
203 
204 int hci_uart_init_ready(struct hci_uart *hu)
205 {
206 	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
207 		return -EALREADY;
208 
209 	schedule_work(&hu->init_ready);
210 
211 	return 0;
212 }
213 
214 /* ------- Interface to HCI layer ------ */
215 /* Initialize device */
216 static int hci_uart_open(struct hci_dev *hdev)
217 {
218 	BT_DBG("%s %p", hdev->name, hdev);
219 
220 	/* Nothing to do for UART driver */
221 	return 0;
222 }
223 
224 /* Reset device */
225 static int hci_uart_flush(struct hci_dev *hdev)
226 {
227 	struct hci_uart *hu  = hci_get_drvdata(hdev);
228 	struct tty_struct *tty = hu->tty;
229 
230 	BT_DBG("hdev %p tty %p", hdev, tty);
231 
232 	if (hu->tx_skb) {
233 		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
234 	}
235 
236 	/* Flush any pending characters in the driver and discipline. */
237 	tty_ldisc_flush(tty);
238 	tty_driver_flush_buffer(tty);
239 
240 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
241 		hu->proto->flush(hu);
242 
243 	return 0;
244 }
245 
246 /* Close device */
247 static int hci_uart_close(struct hci_dev *hdev)
248 {
249 	BT_DBG("hdev %p", hdev);
250 
251 	hci_uart_flush(hdev);
252 	hdev->flush = NULL;
253 	return 0;
254 }
255 
256 /* Send frames from HCI layer */
257 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
258 {
259 	struct hci_uart *hu = hci_get_drvdata(hdev);
260 
261 	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
262 	       skb->len);
263 
264 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
265 		return -EUNATCH;
266 
267 	hu->proto->enqueue(hu, skb);
268 
269 	hci_uart_tx_wakeup(hu);
270 
271 	return 0;
272 }
273 
274 /* Flow control or un-flow control the device */
275 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
276 {
277 	struct tty_struct *tty = hu->tty;
278 	struct ktermios ktermios;
279 	int status;
280 	unsigned int set = 0;
281 	unsigned int clear = 0;
282 
283 	if (enable) {
284 		/* Disable hardware flow control */
285 		ktermios = tty->termios;
286 		ktermios.c_cflag &= ~CRTSCTS;
287 		status = tty_set_termios(tty, &ktermios);
288 		BT_DBG("Disabling hardware flow control: %s",
289 		       status ? "failed" : "success");
290 
291 		/* Clear RTS to prevent the device from sending */
292 		/* Most UARTs need OUT2 to enable interrupts */
293 		status = tty->driver->ops->tiocmget(tty);
294 		BT_DBG("Current tiocm 0x%x", status);
295 
296 		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
297 		clear = ~set;
298 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
299 		       TIOCM_OUT2 | TIOCM_LOOP;
300 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
301 			 TIOCM_OUT2 | TIOCM_LOOP;
302 		status = tty->driver->ops->tiocmset(tty, set, clear);
303 		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
304 	} else {
305 		/* Set RTS to allow the device to send again */
306 		status = tty->driver->ops->tiocmget(tty);
307 		BT_DBG("Current tiocm 0x%x", status);
308 
309 		set |= (TIOCM_OUT2 | TIOCM_RTS);
310 		clear = ~set;
311 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
312 		       TIOCM_OUT2 | TIOCM_LOOP;
313 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
314 			 TIOCM_OUT2 | TIOCM_LOOP;
315 		status = tty->driver->ops->tiocmset(tty, set, clear);
316 		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
317 
318 		/* Re-enable hardware flow control */
319 		ktermios = tty->termios;
320 		ktermios.c_cflag |= CRTSCTS;
321 		status = tty_set_termios(tty, &ktermios);
322 		BT_DBG("Enabling hardware flow control: %s",
323 		       status ? "failed" : "success");
324 	}
325 }
326 
327 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
328 			 unsigned int oper_speed)
329 {
330 	hu->init_speed = init_speed;
331 	hu->oper_speed = oper_speed;
332 }
333 
334 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
335 {
336 	struct tty_struct *tty = hu->tty;
337 	struct ktermios ktermios;
338 
339 	ktermios = tty->termios;
340 	ktermios.c_cflag &= ~CBAUD;
341 	tty_termios_encode_baud_rate(&ktermios, speed, speed);
342 
343 	/* tty_set_termios() return not checked as it is always 0 */
344 	tty_set_termios(tty, &ktermios);
345 
346 	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
347 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
348 }
349 
350 static int hci_uart_setup(struct hci_dev *hdev)
351 {
352 	struct hci_uart *hu = hci_get_drvdata(hdev);
353 	struct hci_rp_read_local_version *ver;
354 	struct sk_buff *skb;
355 	unsigned int speed;
356 	int err;
357 
358 	/* Init speed if any */
359 	if (hu->init_speed)
360 		speed = hu->init_speed;
361 	else if (hu->proto->init_speed)
362 		speed = hu->proto->init_speed;
363 	else
364 		speed = 0;
365 
366 	if (speed)
367 		hci_uart_set_baudrate(hu, speed);
368 
369 	/* Operational speed if any */
370 	if (hu->oper_speed)
371 		speed = hu->oper_speed;
372 	else if (hu->proto->oper_speed)
373 		speed = hu->proto->oper_speed;
374 	else
375 		speed = 0;
376 
377 	if (hu->proto->set_baudrate && speed) {
378 		err = hu->proto->set_baudrate(hu, speed);
379 		if (!err)
380 			hci_uart_set_baudrate(hu, speed);
381 	}
382 
383 	if (hu->proto->setup)
384 		return hu->proto->setup(hu);
385 
386 	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
387 		return 0;
388 
389 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
390 			     HCI_INIT_TIMEOUT);
391 	if (IS_ERR(skb)) {
392 		BT_ERR("%s: Reading local version information failed (%ld)",
393 		       hdev->name, PTR_ERR(skb));
394 		return 0;
395 	}
396 
397 	if (skb->len != sizeof(*ver)) {
398 		BT_ERR("%s: Event length mismatch for version information",
399 		       hdev->name);
400 		goto done;
401 	}
402 
403 	ver = (struct hci_rp_read_local_version *)skb->data;
404 
405 	switch (le16_to_cpu(ver->manufacturer)) {
406 #ifdef CONFIG_BT_HCIUART_INTEL
407 	case 2:
408 		hdev->set_bdaddr = btintel_set_bdaddr;
409 		btintel_check_bdaddr(hdev);
410 		break;
411 #endif
412 #ifdef CONFIG_BT_HCIUART_BCM
413 	case 15:
414 		hdev->set_bdaddr = btbcm_set_bdaddr;
415 		btbcm_check_bdaddr(hdev);
416 		break;
417 #endif
418 	}
419 
420 done:
421 	kfree_skb(skb);
422 	return 0;
423 }
424 
425 /* ------ LDISC part ------ */
426 /* hci_uart_tty_open
427  *
428  *     Called when line discipline changed to HCI_UART.
429  *
430  * Arguments:
431  *     tty    pointer to tty info structure
432  * Return Value:
433  *     0 if success, otherwise error code
434  */
435 static int hci_uart_tty_open(struct tty_struct *tty)
436 {
437 	struct hci_uart *hu;
438 
439 	BT_DBG("tty %p", tty);
440 
441 	/* Error if the tty has no write op instead of leaving an exploitable
442 	   hole */
443 	if (tty->ops->write == NULL)
444 		return -EOPNOTSUPP;
445 
446 	hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
447 	if (!hu) {
448 		BT_ERR("Can't allocate control structure");
449 		return -ENFILE;
450 	}
451 
452 	tty->disc_data = hu;
453 	hu->tty = tty;
454 	tty->receive_room = 65536;
455 
456 	/* disable alignment support by default */
457 	hu->alignment = 1;
458 	hu->padding = 0;
459 
460 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
461 	INIT_WORK(&hu->write_work, hci_uart_write_work);
462 
463 	/* Flush any pending characters in the driver */
464 	tty_driver_flush_buffer(tty);
465 
466 	return 0;
467 }
468 
469 /* hci_uart_tty_close()
470  *
471  *    Called when the line discipline is changed to something
472  *    else, the tty is closed, or the tty detects a hangup.
473  */
474 static void hci_uart_tty_close(struct tty_struct *tty)
475 {
476 	struct hci_uart *hu = tty->disc_data;
477 	struct hci_dev *hdev;
478 
479 	BT_DBG("tty %p", tty);
480 
481 	/* Detach from the tty */
482 	tty->disc_data = NULL;
483 
484 	if (!hu)
485 		return;
486 
487 	hdev = hu->hdev;
488 	if (hdev)
489 		hci_uart_close(hdev);
490 
491 	cancel_work_sync(&hu->write_work);
492 
493 	if (test_and_clear_bit(HCI_UART_PROTO_READY, &hu->flags)) {
494 		if (hdev) {
495 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
496 				hci_unregister_dev(hdev);
497 			hci_free_dev(hdev);
498 		}
499 		hu->proto->close(hu);
500 	}
501 	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
502 
503 	kfree(hu);
504 }
505 
506 /* hci_uart_tty_wakeup()
507  *
508  *    Callback for transmit wakeup. Called when low level
509  *    device driver can accept more send data.
510  *
511  * Arguments:        tty    pointer to associated tty instance data
512  * Return Value:    None
513  */
514 static void hci_uart_tty_wakeup(struct tty_struct *tty)
515 {
516 	struct hci_uart *hu = tty->disc_data;
517 
518 	BT_DBG("");
519 
520 	if (!hu)
521 		return;
522 
523 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
524 
525 	if (tty != hu->tty)
526 		return;
527 
528 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
529 		hci_uart_tx_wakeup(hu);
530 }
531 
532 /* hci_uart_tty_receive()
533  *
534  *     Called by tty low level driver when receive data is
535  *     available.
536  *
537  * Arguments:  tty          pointer to tty isntance data
538  *             data         pointer to received data
539  *             flags        pointer to flags for data
540  *             count        count of received data in bytes
541  *
542  * Return Value:    None
543  */
544 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
545 				 char *flags, int count)
546 {
547 	struct hci_uart *hu = tty->disc_data;
548 
549 	if (!hu || tty != hu->tty)
550 		return;
551 
552 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
553 		return;
554 
555 	/* It does not need a lock here as it is already protected by a mutex in
556 	 * tty caller
557 	 */
558 	hu->proto->recv(hu, data, count);
559 
560 	if (hu->hdev)
561 		hu->hdev->stat.byte_rx += count;
562 
563 	tty_unthrottle(tty);
564 }
565 
566 static int hci_uart_register_dev(struct hci_uart *hu)
567 {
568 	struct hci_dev *hdev;
569 
570 	BT_DBG("");
571 
572 	/* Initialize and register HCI device */
573 	hdev = hci_alloc_dev();
574 	if (!hdev) {
575 		BT_ERR("Can't allocate HCI device");
576 		return -ENOMEM;
577 	}
578 
579 	hu->hdev = hdev;
580 
581 	hdev->bus = HCI_UART;
582 	hci_set_drvdata(hdev, hu);
583 
584 	/* Only when vendor specific setup callback is provided, consider
585 	 * the manufacturer information valid. This avoids filling in the
586 	 * value for Ericsson when nothing is specified.
587 	 */
588 	if (hu->proto->setup)
589 		hdev->manufacturer = hu->proto->manufacturer;
590 
591 	hdev->open  = hci_uart_open;
592 	hdev->close = hci_uart_close;
593 	hdev->flush = hci_uart_flush;
594 	hdev->send  = hci_uart_send_frame;
595 	hdev->setup = hci_uart_setup;
596 	SET_HCIDEV_DEV(hdev, hu->tty->dev);
597 
598 	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
599 		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
600 
601 	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
602 		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
603 
604 	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
605 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
606 
607 	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
608 		hdev->dev_type = HCI_AMP;
609 	else
610 		hdev->dev_type = HCI_PRIMARY;
611 
612 	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
613 		return 0;
614 
615 	if (hci_register_dev(hdev) < 0) {
616 		BT_ERR("Can't register HCI device");
617 		hu->hdev = NULL;
618 		hci_free_dev(hdev);
619 		return -ENODEV;
620 	}
621 
622 	set_bit(HCI_UART_REGISTERED, &hu->flags);
623 
624 	return 0;
625 }
626 
627 static int hci_uart_set_proto(struct hci_uart *hu, int id)
628 {
629 	const struct hci_uart_proto *p;
630 	int err;
631 
632 	p = hci_uart_get_proto(id);
633 	if (!p)
634 		return -EPROTONOSUPPORT;
635 
636 	err = p->open(hu);
637 	if (err)
638 		return err;
639 
640 	hu->proto = p;
641 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
642 
643 	err = hci_uart_register_dev(hu);
644 	if (err) {
645 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
646 		p->close(hu);
647 		return err;
648 	}
649 
650 	return 0;
651 }
652 
653 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
654 {
655 	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
656 				    BIT(HCI_UART_RESET_ON_INIT) |
657 				    BIT(HCI_UART_CREATE_AMP) |
658 				    BIT(HCI_UART_INIT_PENDING) |
659 				    BIT(HCI_UART_EXT_CONFIG) |
660 				    BIT(HCI_UART_VND_DETECT);
661 
662 	if (flags & ~valid_flags)
663 		return -EINVAL;
664 
665 	hu->hdev_flags = flags;
666 
667 	return 0;
668 }
669 
670 /* hci_uart_tty_ioctl()
671  *
672  *    Process IOCTL system call for the tty device.
673  *
674  * Arguments:
675  *
676  *    tty        pointer to tty instance data
677  *    file       pointer to open file object for device
678  *    cmd        IOCTL command code
679  *    arg        argument for IOCTL call (cmd dependent)
680  *
681  * Return Value:    Command dependent
682  */
683 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
684 			      unsigned int cmd, unsigned long arg)
685 {
686 	struct hci_uart *hu = tty->disc_data;
687 	int err = 0;
688 
689 	BT_DBG("");
690 
691 	/* Verify the status of the device */
692 	if (!hu)
693 		return -EBADF;
694 
695 	switch (cmd) {
696 	case HCIUARTSETPROTO:
697 		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
698 			err = hci_uart_set_proto(hu, arg);
699 			if (err)
700 				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
701 		} else
702 			err = -EBUSY;
703 		break;
704 
705 	case HCIUARTGETPROTO:
706 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
707 			err = hu->proto->id;
708 		else
709 			err = -EUNATCH;
710 		break;
711 
712 	case HCIUARTGETDEVICE:
713 		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
714 			err = hu->hdev->id;
715 		else
716 			err = -EUNATCH;
717 		break;
718 
719 	case HCIUARTSETFLAGS:
720 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
721 			err = -EBUSY;
722 		else
723 			err = hci_uart_set_flags(hu, arg);
724 		break;
725 
726 	case HCIUARTGETFLAGS:
727 		err = hu->hdev_flags;
728 		break;
729 
730 	default:
731 		err = n_tty_ioctl_helper(tty, file, cmd, arg);
732 		break;
733 	}
734 
735 	return err;
736 }
737 
738 /*
739  * We don't provide read/write/poll interface for user space.
740  */
741 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
742 				 unsigned char __user *buf, size_t nr)
743 {
744 	return 0;
745 }
746 
747 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
748 				  const unsigned char *data, size_t count)
749 {
750 	return 0;
751 }
752 
753 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
754 				      struct file *filp, poll_table *wait)
755 {
756 	return 0;
757 }
758 
759 static int __init hci_uart_init(void)
760 {
761 	static struct tty_ldisc_ops hci_uart_ldisc;
762 	int err;
763 
764 	BT_INFO("HCI UART driver ver %s", VERSION);
765 
766 	/* Register the tty discipline */
767 
768 	memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
769 	hci_uart_ldisc.magic		= TTY_LDISC_MAGIC;
770 	hci_uart_ldisc.name		= "n_hci";
771 	hci_uart_ldisc.open		= hci_uart_tty_open;
772 	hci_uart_ldisc.close		= hci_uart_tty_close;
773 	hci_uart_ldisc.read		= hci_uart_tty_read;
774 	hci_uart_ldisc.write		= hci_uart_tty_write;
775 	hci_uart_ldisc.ioctl		= hci_uart_tty_ioctl;
776 	hci_uart_ldisc.poll		= hci_uart_tty_poll;
777 	hci_uart_ldisc.receive_buf	= hci_uart_tty_receive;
778 	hci_uart_ldisc.write_wakeup	= hci_uart_tty_wakeup;
779 	hci_uart_ldisc.owner		= THIS_MODULE;
780 
781 	err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
782 	if (err) {
783 		BT_ERR("HCI line discipline registration failed. (%d)", err);
784 		return err;
785 	}
786 
787 #ifdef CONFIG_BT_HCIUART_H4
788 	h4_init();
789 #endif
790 #ifdef CONFIG_BT_HCIUART_BCSP
791 	bcsp_init();
792 #endif
793 #ifdef CONFIG_BT_HCIUART_LL
794 	ll_init();
795 #endif
796 #ifdef CONFIG_BT_HCIUART_ATH3K
797 	ath_init();
798 #endif
799 #ifdef CONFIG_BT_HCIUART_3WIRE
800 	h5_init();
801 #endif
802 #ifdef CONFIG_BT_HCIUART_INTEL
803 	intel_init();
804 #endif
805 #ifdef CONFIG_BT_HCIUART_BCM
806 	bcm_init();
807 #endif
808 #ifdef CONFIG_BT_HCIUART_QCA
809 	qca_init();
810 #endif
811 #ifdef CONFIG_BT_HCIUART_AG6XX
812 	ag6xx_init();
813 #endif
814 #ifdef CONFIG_BT_HCIUART_MRVL
815 	mrvl_init();
816 #endif
817 
818 	return 0;
819 }
820 
821 static void __exit hci_uart_exit(void)
822 {
823 	int err;
824 
825 #ifdef CONFIG_BT_HCIUART_H4
826 	h4_deinit();
827 #endif
828 #ifdef CONFIG_BT_HCIUART_BCSP
829 	bcsp_deinit();
830 #endif
831 #ifdef CONFIG_BT_HCIUART_LL
832 	ll_deinit();
833 #endif
834 #ifdef CONFIG_BT_HCIUART_ATH3K
835 	ath_deinit();
836 #endif
837 #ifdef CONFIG_BT_HCIUART_3WIRE
838 	h5_deinit();
839 #endif
840 #ifdef CONFIG_BT_HCIUART_INTEL
841 	intel_deinit();
842 #endif
843 #ifdef CONFIG_BT_HCIUART_BCM
844 	bcm_deinit();
845 #endif
846 #ifdef CONFIG_BT_HCIUART_QCA
847 	qca_deinit();
848 #endif
849 #ifdef CONFIG_BT_HCIUART_AG6XX
850 	ag6xx_deinit();
851 #endif
852 #ifdef CONFIG_BT_HCIUART_MRVL
853 	mrvl_deinit();
854 #endif
855 
856 	/* Release tty registration of line discipline */
857 	err = tty_unregister_ldisc(N_HCI);
858 	if (err)
859 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
860 }
861 
862 module_init(hci_uart_init);
863 module_exit(hci_uart_exit);
864 
865 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
866 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
867 MODULE_VERSION(VERSION);
868 MODULE_LICENSE("GPL");
869 MODULE_ALIAS_LDISC(N_HCI);
870