xref: /openbmc/linux/drivers/bluetooth/hci_ldisc.c (revision 9cfc5c90)
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 		skb = hu->proto->dequeue(hu);
118 	else
119 		hu->tx_skb = NULL;
120 
121 	return skb;
122 }
123 
124 int hci_uart_tx_wakeup(struct hci_uart *hu)
125 {
126 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
127 		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
128 		return 0;
129 	}
130 
131 	BT_DBG("");
132 
133 	schedule_work(&hu->write_work);
134 
135 	return 0;
136 }
137 
138 static void hci_uart_write_work(struct work_struct *work)
139 {
140 	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
141 	struct tty_struct *tty = hu->tty;
142 	struct hci_dev *hdev = hu->hdev;
143 	struct sk_buff *skb;
144 
145 	/* REVISIT: should we cope with bad skbs or ->write() returning
146 	 * and error value ?
147 	 */
148 
149 restart:
150 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
151 
152 	while ((skb = hci_uart_dequeue(hu))) {
153 		int len;
154 
155 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
156 		len = tty->ops->write(tty, skb->data, skb->len);
157 		hdev->stat.byte_tx += len;
158 
159 		skb_pull(skb, len);
160 		if (skb->len) {
161 			hu->tx_skb = skb;
162 			break;
163 		}
164 
165 		hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
166 		kfree_skb(skb);
167 	}
168 
169 	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
170 		goto restart;
171 
172 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
173 }
174 
175 static void hci_uart_init_work(struct work_struct *work)
176 {
177 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
178 	int err;
179 
180 	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
181 		return;
182 
183 	err = hci_register_dev(hu->hdev);
184 	if (err < 0) {
185 		BT_ERR("Can't register HCI device");
186 		hci_free_dev(hu->hdev);
187 		hu->hdev = NULL;
188 		hu->proto->close(hu);
189 	}
190 
191 	set_bit(HCI_UART_REGISTERED, &hu->flags);
192 }
193 
194 int hci_uart_init_ready(struct hci_uart *hu)
195 {
196 	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
197 		return -EALREADY;
198 
199 	schedule_work(&hu->init_ready);
200 
201 	return 0;
202 }
203 
204 /* ------- Interface to HCI layer ------ */
205 /* Initialize device */
206 static int hci_uart_open(struct hci_dev *hdev)
207 {
208 	BT_DBG("%s %p", hdev->name, hdev);
209 
210 	/* Nothing to do for UART driver */
211 	return 0;
212 }
213 
214 /* Reset device */
215 static int hci_uart_flush(struct hci_dev *hdev)
216 {
217 	struct hci_uart *hu  = hci_get_drvdata(hdev);
218 	struct tty_struct *tty = hu->tty;
219 
220 	BT_DBG("hdev %p tty %p", hdev, tty);
221 
222 	if (hu->tx_skb) {
223 		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
224 	}
225 
226 	/* Flush any pending characters in the driver and discipline. */
227 	tty_ldisc_flush(tty);
228 	tty_driver_flush_buffer(tty);
229 
230 	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
231 		hu->proto->flush(hu);
232 
233 	return 0;
234 }
235 
236 /* Close device */
237 static int hci_uart_close(struct hci_dev *hdev)
238 {
239 	BT_DBG("hdev %p", hdev);
240 
241 	hci_uart_flush(hdev);
242 	hdev->flush = NULL;
243 	return 0;
244 }
245 
246 /* Send frames from HCI layer */
247 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
248 {
249 	struct hci_uart *hu = hci_get_drvdata(hdev);
250 
251 	BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
252 
253 	hu->proto->enqueue(hu, skb);
254 
255 	hci_uart_tx_wakeup(hu);
256 
257 	return 0;
258 }
259 
260 /* Flow control or un-flow control the device */
261 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
262 {
263 	struct tty_struct *tty = hu->tty;
264 	struct ktermios ktermios;
265 	int status;
266 	unsigned int set = 0;
267 	unsigned int clear = 0;
268 
269 	if (enable) {
270 		/* Disable hardware flow control */
271 		ktermios = tty->termios;
272 		ktermios.c_cflag &= ~CRTSCTS;
273 		status = tty_set_termios(tty, &ktermios);
274 		BT_DBG("Disabling hardware flow control: %s",
275 		       status ? "failed" : "success");
276 
277 		/* Clear RTS to prevent the device from sending */
278 		/* Most UARTs need OUT2 to enable interrupts */
279 		status = tty->driver->ops->tiocmget(tty);
280 		BT_DBG("Current tiocm 0x%x", status);
281 
282 		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
283 		clear = ~set;
284 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
285 		       TIOCM_OUT2 | TIOCM_LOOP;
286 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
287 			 TIOCM_OUT2 | TIOCM_LOOP;
288 		status = tty->driver->ops->tiocmset(tty, set, clear);
289 		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
290 	} else {
291 		/* Set RTS to allow the device to send again */
292 		status = tty->driver->ops->tiocmget(tty);
293 		BT_DBG("Current tiocm 0x%x", status);
294 
295 		set |= (TIOCM_OUT2 | TIOCM_RTS);
296 		clear = ~set;
297 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
298 		       TIOCM_OUT2 | TIOCM_LOOP;
299 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
300 			 TIOCM_OUT2 | TIOCM_LOOP;
301 		status = tty->driver->ops->tiocmset(tty, set, clear);
302 		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
303 
304 		/* Re-enable hardware flow control */
305 		ktermios = tty->termios;
306 		ktermios.c_cflag |= CRTSCTS;
307 		status = tty_set_termios(tty, &ktermios);
308 		BT_DBG("Enabling hardware flow control: %s",
309 		       status ? "failed" : "success");
310 	}
311 }
312 
313 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
314 			 unsigned int oper_speed)
315 {
316 	hu->init_speed = init_speed;
317 	hu->oper_speed = oper_speed;
318 }
319 
320 void hci_uart_init_tty(struct hci_uart *hu)
321 {
322 	struct tty_struct *tty = hu->tty;
323 	struct ktermios ktermios;
324 
325 	/* Bring the UART into a known 8 bits no parity hw fc state */
326 	ktermios = tty->termios;
327 	ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
328 			      INLCR | IGNCR | ICRNL | IXON);
329 	ktermios.c_oflag &= ~OPOST;
330 	ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
331 	ktermios.c_cflag &= ~(CSIZE | PARENB);
332 	ktermios.c_cflag |= CS8;
333 	ktermios.c_cflag |= CRTSCTS;
334 
335 	/* tty_set_termios() return not checked as it is always 0 */
336 	tty_set_termios(tty, &ktermios);
337 }
338 
339 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
340 {
341 	struct tty_struct *tty = hu->tty;
342 	struct ktermios ktermios;
343 
344 	ktermios = tty->termios;
345 	ktermios.c_cflag &= ~CBAUD;
346 	tty_termios_encode_baud_rate(&ktermios, speed, speed);
347 
348 	/* tty_set_termios() return not checked as it is always 0 */
349 	tty_set_termios(tty, &ktermios);
350 
351 	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
352 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
353 }
354 
355 static int hci_uart_setup(struct hci_dev *hdev)
356 {
357 	struct hci_uart *hu = hci_get_drvdata(hdev);
358 	struct hci_rp_read_local_version *ver;
359 	struct sk_buff *skb;
360 	unsigned int speed;
361 	int err;
362 
363 	/* Init speed if any */
364 	if (hu->init_speed)
365 		speed = hu->init_speed;
366 	else if (hu->proto->init_speed)
367 		speed = hu->proto->init_speed;
368 	else
369 		speed = 0;
370 
371 	if (speed)
372 		hci_uart_set_baudrate(hu, speed);
373 
374 	/* Operational speed if any */
375 	if (hu->oper_speed)
376 		speed = hu->oper_speed;
377 	else if (hu->proto->oper_speed)
378 		speed = hu->proto->oper_speed;
379 	else
380 		speed = 0;
381 
382 	if (hu->proto->set_baudrate && speed) {
383 		err = hu->proto->set_baudrate(hu, speed);
384 		if (!err)
385 			hci_uart_set_baudrate(hu, speed);
386 	}
387 
388 	if (hu->proto->setup)
389 		return hu->proto->setup(hu);
390 
391 	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
392 		return 0;
393 
394 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
395 			     HCI_INIT_TIMEOUT);
396 	if (IS_ERR(skb)) {
397 		BT_ERR("%s: Reading local version information failed (%ld)",
398 		       hdev->name, PTR_ERR(skb));
399 		return 0;
400 	}
401 
402 	if (skb->len != sizeof(*ver)) {
403 		BT_ERR("%s: Event length mismatch for version information",
404 		       hdev->name);
405 		goto done;
406 	}
407 
408 	ver = (struct hci_rp_read_local_version *)skb->data;
409 
410 	switch (le16_to_cpu(ver->manufacturer)) {
411 #ifdef CONFIG_BT_HCIUART_INTEL
412 	case 2:
413 		hdev->set_bdaddr = btintel_set_bdaddr;
414 		btintel_check_bdaddr(hdev);
415 		break;
416 #endif
417 #ifdef CONFIG_BT_HCIUART_BCM
418 	case 15:
419 		hdev->set_bdaddr = btbcm_set_bdaddr;
420 		btbcm_check_bdaddr(hdev);
421 		break;
422 #endif
423 	}
424 
425 done:
426 	kfree_skb(skb);
427 	return 0;
428 }
429 
430 /* ------ LDISC part ------ */
431 /* hci_uart_tty_open
432  *
433  *     Called when line discipline changed to HCI_UART.
434  *
435  * Arguments:
436  *     tty    pointer to tty info structure
437  * Return Value:
438  *     0 if success, otherwise error code
439  */
440 static int hci_uart_tty_open(struct tty_struct *tty)
441 {
442 	struct hci_uart *hu;
443 
444 	BT_DBG("tty %p", tty);
445 
446 	/* Error if the tty has no write op instead of leaving an exploitable
447 	   hole */
448 	if (tty->ops->write == NULL)
449 		return -EOPNOTSUPP;
450 
451 	hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
452 	if (!hu) {
453 		BT_ERR("Can't allocate control structure");
454 		return -ENFILE;
455 	}
456 
457 	tty->disc_data = hu;
458 	hu->tty = tty;
459 	tty->receive_room = 65536;
460 
461 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
462 	INIT_WORK(&hu->write_work, hci_uart_write_work);
463 
464 	/* Flush any pending characters in the driver and line discipline. */
465 
466 	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
467 	   open path is before the ldisc is referencable */
468 
469 	if (tty->ldisc->ops->flush_buffer)
470 		tty->ldisc->ops->flush_buffer(tty);
471 	tty_driver_flush_buffer(tty);
472 
473 	return 0;
474 }
475 
476 /* hci_uart_tty_close()
477  *
478  *    Called when the line discipline is changed to something
479  *    else, the tty is closed, or the tty detects a hangup.
480  */
481 static void hci_uart_tty_close(struct tty_struct *tty)
482 {
483 	struct hci_uart *hu = tty->disc_data;
484 	struct hci_dev *hdev;
485 
486 	BT_DBG("tty %p", tty);
487 
488 	/* Detach from the tty */
489 	tty->disc_data = NULL;
490 
491 	if (!hu)
492 		return;
493 
494 	hdev = hu->hdev;
495 	if (hdev)
496 		hci_uart_close(hdev);
497 
498 	cancel_work_sync(&hu->write_work);
499 
500 	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
501 		if (hdev) {
502 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
503 				hci_unregister_dev(hdev);
504 			hci_free_dev(hdev);
505 		}
506 		hu->proto->close(hu);
507 	}
508 
509 	kfree(hu);
510 }
511 
512 /* hci_uart_tty_wakeup()
513  *
514  *    Callback for transmit wakeup. Called when low level
515  *    device driver can accept more send data.
516  *
517  * Arguments:        tty    pointer to associated tty instance data
518  * Return Value:    None
519  */
520 static void hci_uart_tty_wakeup(struct tty_struct *tty)
521 {
522 	struct hci_uart *hu = tty->disc_data;
523 
524 	BT_DBG("");
525 
526 	if (!hu)
527 		return;
528 
529 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
530 
531 	if (tty != hu->tty)
532 		return;
533 
534 	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
535 		hci_uart_tx_wakeup(hu);
536 }
537 
538 /* hci_uart_tty_receive()
539  *
540  *     Called by tty low level driver when receive data is
541  *     available.
542  *
543  * Arguments:  tty          pointer to tty isntance data
544  *             data         pointer to received data
545  *             flags        pointer to flags for data
546  *             count        count of received data in bytes
547  *
548  * Return Value:    None
549  */
550 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
551 				 char *flags, int count)
552 {
553 	struct hci_uart *hu = tty->disc_data;
554 
555 	if (!hu || tty != hu->tty)
556 		return;
557 
558 	if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
559 		return;
560 
561 	/* It does not need a lock here as it is already protected by a mutex in
562 	 * tty caller
563 	 */
564 	hu->proto->recv(hu, data, count);
565 
566 	if (hu->hdev)
567 		hu->hdev->stat.byte_rx += count;
568 
569 	tty_unthrottle(tty);
570 }
571 
572 static int hci_uart_register_dev(struct hci_uart *hu)
573 {
574 	struct hci_dev *hdev;
575 
576 	BT_DBG("");
577 
578 	/* Initialize and register HCI device */
579 	hdev = hci_alloc_dev();
580 	if (!hdev) {
581 		BT_ERR("Can't allocate HCI device");
582 		return -ENOMEM;
583 	}
584 
585 	hu->hdev = hdev;
586 
587 	hdev->bus = HCI_UART;
588 	hci_set_drvdata(hdev, hu);
589 
590 	/* Only when vendor specific setup callback is provided, consider
591 	 * the manufacturer information valid. This avoids filling in the
592 	 * value for Ericsson when nothing is specified.
593 	 */
594 	if (hu->proto->setup)
595 		hdev->manufacturer = hu->proto->manufacturer;
596 
597 	hdev->open  = hci_uart_open;
598 	hdev->close = hci_uart_close;
599 	hdev->flush = hci_uart_flush;
600 	hdev->send  = hci_uart_send_frame;
601 	hdev->setup = hci_uart_setup;
602 	SET_HCIDEV_DEV(hdev, hu->tty->dev);
603 
604 	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
605 		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
606 
607 	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
608 		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
609 
610 	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
611 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
612 
613 	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
614 		hdev->dev_type = HCI_AMP;
615 	else
616 		hdev->dev_type = HCI_BREDR;
617 
618 	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
619 		return 0;
620 
621 	if (hci_register_dev(hdev) < 0) {
622 		BT_ERR("Can't register HCI device");
623 		hci_free_dev(hdev);
624 		return -ENODEV;
625 	}
626 
627 	set_bit(HCI_UART_REGISTERED, &hu->flags);
628 
629 	return 0;
630 }
631 
632 static int hci_uart_set_proto(struct hci_uart *hu, int id)
633 {
634 	const struct hci_uart_proto *p;
635 	int err;
636 
637 	p = hci_uart_get_proto(id);
638 	if (!p)
639 		return -EPROTONOSUPPORT;
640 
641 	err = p->open(hu);
642 	if (err)
643 		return err;
644 
645 	hu->proto = p;
646 
647 	err = hci_uart_register_dev(hu);
648 	if (err) {
649 		p->close(hu);
650 		return err;
651 	}
652 
653 	return 0;
654 }
655 
656 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
657 {
658 	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
659 				    BIT(HCI_UART_RESET_ON_INIT) |
660 				    BIT(HCI_UART_CREATE_AMP) |
661 				    BIT(HCI_UART_INIT_PENDING) |
662 				    BIT(HCI_UART_EXT_CONFIG) |
663 				    BIT(HCI_UART_VND_DETECT);
664 
665 	if (flags & ~valid_flags)
666 		return -EINVAL;
667 
668 	hu->hdev_flags = flags;
669 
670 	return 0;
671 }
672 
673 /* hci_uart_tty_ioctl()
674  *
675  *    Process IOCTL system call for the tty device.
676  *
677  * Arguments:
678  *
679  *    tty        pointer to tty instance data
680  *    file       pointer to open file object for device
681  *    cmd        IOCTL command code
682  *    arg        argument for IOCTL call (cmd dependent)
683  *
684  * Return Value:    Command dependent
685  */
686 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
687 			      unsigned int cmd, unsigned long arg)
688 {
689 	struct hci_uart *hu = tty->disc_data;
690 	int err = 0;
691 
692 	BT_DBG("");
693 
694 	/* Verify the status of the device */
695 	if (!hu)
696 		return -EBADF;
697 
698 	switch (cmd) {
699 	case HCIUARTSETPROTO:
700 		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
701 			err = hci_uart_set_proto(hu, arg);
702 			if (err) {
703 				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
704 				return err;
705 			}
706 		} else
707 			return -EBUSY;
708 		break;
709 
710 	case HCIUARTGETPROTO:
711 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
712 			return hu->proto->id;
713 		return -EUNATCH;
714 
715 	case HCIUARTGETDEVICE:
716 		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
717 			return hu->hdev->id;
718 		return -EUNATCH;
719 
720 	case HCIUARTSETFLAGS:
721 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
722 			return -EBUSY;
723 		err = hci_uart_set_flags(hu, arg);
724 		if (err)
725 			return err;
726 		break;
727 
728 	case HCIUARTGETFLAGS:
729 		return hu->hdev_flags;
730 
731 	default:
732 		err = n_tty_ioctl_helper(tty, file, cmd, arg);
733 		break;
734 	}
735 
736 	return err;
737 }
738 
739 /*
740  * We don't provide read/write/poll interface for user space.
741  */
742 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
743 				 unsigned char __user *buf, size_t nr)
744 {
745 	return 0;
746 }
747 
748 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
749 				  const unsigned char *data, size_t count)
750 {
751 	return 0;
752 }
753 
754 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
755 				      struct file *filp, poll_table *wait)
756 {
757 	return 0;
758 }
759 
760 static int __init hci_uart_init(void)
761 {
762 	static struct tty_ldisc_ops hci_uart_ldisc;
763 	int err;
764 
765 	BT_INFO("HCI UART driver ver %s", VERSION);
766 
767 	/* Register the tty discipline */
768 
769 	memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
770 	hci_uart_ldisc.magic		= TTY_LDISC_MAGIC;
771 	hci_uart_ldisc.name		= "n_hci";
772 	hci_uart_ldisc.open		= hci_uart_tty_open;
773 	hci_uart_ldisc.close		= hci_uart_tty_close;
774 	hci_uart_ldisc.read		= hci_uart_tty_read;
775 	hci_uart_ldisc.write		= hci_uart_tty_write;
776 	hci_uart_ldisc.ioctl		= hci_uart_tty_ioctl;
777 	hci_uart_ldisc.poll		= hci_uart_tty_poll;
778 	hci_uart_ldisc.receive_buf	= hci_uart_tty_receive;
779 	hci_uart_ldisc.write_wakeup	= hci_uart_tty_wakeup;
780 	hci_uart_ldisc.owner		= THIS_MODULE;
781 
782 	err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
783 	if (err) {
784 		BT_ERR("HCI line discipline registration failed. (%d)", err);
785 		return err;
786 	}
787 
788 #ifdef CONFIG_BT_HCIUART_H4
789 	h4_init();
790 #endif
791 #ifdef CONFIG_BT_HCIUART_BCSP
792 	bcsp_init();
793 #endif
794 #ifdef CONFIG_BT_HCIUART_LL
795 	ll_init();
796 #endif
797 #ifdef CONFIG_BT_HCIUART_ATH3K
798 	ath_init();
799 #endif
800 #ifdef CONFIG_BT_HCIUART_3WIRE
801 	h5_init();
802 #endif
803 #ifdef CONFIG_BT_HCIUART_INTEL
804 	intel_init();
805 #endif
806 #ifdef CONFIG_BT_HCIUART_BCM
807 	bcm_init();
808 #endif
809 #ifdef CONFIG_BT_HCIUART_QCA
810 	qca_init();
811 #endif
812 
813 	return 0;
814 }
815 
816 static void __exit hci_uart_exit(void)
817 {
818 	int err;
819 
820 #ifdef CONFIG_BT_HCIUART_H4
821 	h4_deinit();
822 #endif
823 #ifdef CONFIG_BT_HCIUART_BCSP
824 	bcsp_deinit();
825 #endif
826 #ifdef CONFIG_BT_HCIUART_LL
827 	ll_deinit();
828 #endif
829 #ifdef CONFIG_BT_HCIUART_ATH3K
830 	ath_deinit();
831 #endif
832 #ifdef CONFIG_BT_HCIUART_3WIRE
833 	h5_deinit();
834 #endif
835 #ifdef CONFIG_BT_HCIUART_INTEL
836 	intel_deinit();
837 #endif
838 #ifdef CONFIG_BT_HCIUART_BCM
839 	bcm_deinit();
840 #endif
841 #ifdef CONFIG_BT_HCIUART_QCA
842 	qca_deinit();
843 #endif
844 
845 	/* Release tty registration of line discipline */
846 	err = tty_unregister_ldisc(N_HCI);
847 	if (err)
848 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
849 }
850 
851 module_init(hci_uart_init);
852 module_exit(hci_uart_exit);
853 
854 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
855 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
856 MODULE_VERSION(VERSION);
857 MODULE_LICENSE("GPL");
858 MODULE_ALIAS_LDISC(N_HCI);
859