xref: /openbmc/linux/drivers/bluetooth/hci_ldisc.c (revision d2ba09c1)
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 #include <linux/serdev.h>
45 
46 #include <net/bluetooth/bluetooth.h>
47 #include <net/bluetooth/hci_core.h>
48 
49 #include "btintel.h"
50 #include "btbcm.h"
51 #include "hci_uart.h"
52 
53 #define VERSION "2.3"
54 
55 static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
56 
57 int hci_uart_register_proto(const struct hci_uart_proto *p)
58 {
59 	if (p->id >= HCI_UART_MAX_PROTO)
60 		return -EINVAL;
61 
62 	if (hup[p->id])
63 		return -EEXIST;
64 
65 	hup[p->id] = p;
66 
67 	BT_INFO("HCI UART protocol %s registered", p->name);
68 
69 	return 0;
70 }
71 
72 int hci_uart_unregister_proto(const struct hci_uart_proto *p)
73 {
74 	if (p->id >= HCI_UART_MAX_PROTO)
75 		return -EINVAL;
76 
77 	if (!hup[p->id])
78 		return -EINVAL;
79 
80 	hup[p->id] = NULL;
81 
82 	return 0;
83 }
84 
85 static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
86 {
87 	if (id >= HCI_UART_MAX_PROTO)
88 		return NULL;
89 
90 	return hup[id];
91 }
92 
93 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
94 {
95 	struct hci_dev *hdev = hu->hdev;
96 
97 	/* Update HCI stat counters */
98 	switch (pkt_type) {
99 	case HCI_COMMAND_PKT:
100 		hdev->stat.cmd_tx++;
101 		break;
102 
103 	case HCI_ACLDATA_PKT:
104 		hdev->stat.acl_tx++;
105 		break;
106 
107 	case HCI_SCODATA_PKT:
108 		hdev->stat.sco_tx++;
109 		break;
110 	}
111 }
112 
113 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
114 {
115 	struct sk_buff *skb = hu->tx_skb;
116 
117 	if (!skb) {
118 		percpu_down_read(&hu->proto_lock);
119 
120 		if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
121 			skb = hu->proto->dequeue(hu);
122 
123 		percpu_up_read(&hu->proto_lock);
124 	} else {
125 		hu->tx_skb = NULL;
126 	}
127 
128 	return skb;
129 }
130 
131 int hci_uart_tx_wakeup(struct hci_uart *hu)
132 {
133 	/* This may be called in an IRQ context, so we can't sleep. Therefore
134 	 * we try to acquire the lock only, and if that fails we assume the
135 	 * tty is being closed because that is the only time the write lock is
136 	 * acquired. If, however, at some point in the future the write lock
137 	 * is also acquired in other situations, then this must be revisited.
138 	 */
139 	if (!percpu_down_read_trylock(&hu->proto_lock))
140 		return 0;
141 
142 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
143 		goto no_schedule;
144 
145 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
146 		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
147 		goto no_schedule;
148 	}
149 
150 	BT_DBG("");
151 
152 	schedule_work(&hu->write_work);
153 
154 no_schedule:
155 	percpu_up_read(&hu->proto_lock);
156 
157 	return 0;
158 }
159 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
160 
161 static void hci_uart_write_work(struct work_struct *work)
162 {
163 	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
164 	struct tty_struct *tty = hu->tty;
165 	struct hci_dev *hdev = hu->hdev;
166 	struct sk_buff *skb;
167 
168 	/* REVISIT: should we cope with bad skbs or ->write() returning
169 	 * and error value ?
170 	 */
171 
172 restart:
173 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
174 
175 	while ((skb = hci_uart_dequeue(hu))) {
176 		int len;
177 
178 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
179 		len = tty->ops->write(tty, skb->data, skb->len);
180 		hdev->stat.byte_tx += len;
181 
182 		skb_pull(skb, len);
183 		if (skb->len) {
184 			hu->tx_skb = skb;
185 			break;
186 		}
187 
188 		hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
189 		kfree_skb(skb);
190 	}
191 
192 	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
193 		goto restart;
194 
195 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
196 }
197 
198 static void hci_uart_init_work(struct work_struct *work)
199 {
200 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
201 	int err;
202 	struct hci_dev *hdev;
203 
204 	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
205 		return;
206 
207 	err = hci_register_dev(hu->hdev);
208 	if (err < 0) {
209 		BT_ERR("Can't register HCI device");
210 		hdev = hu->hdev;
211 		hu->hdev = NULL;
212 		hci_free_dev(hdev);
213 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
214 		hu->proto->close(hu);
215 		return;
216 	}
217 
218 	set_bit(HCI_UART_REGISTERED, &hu->flags);
219 }
220 
221 int hci_uart_init_ready(struct hci_uart *hu)
222 {
223 	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
224 		return -EALREADY;
225 
226 	schedule_work(&hu->init_ready);
227 
228 	return 0;
229 }
230 
231 /* ------- Interface to HCI layer ------ */
232 /* Initialize device */
233 static int hci_uart_open(struct hci_dev *hdev)
234 {
235 	BT_DBG("%s %p", hdev->name, hdev);
236 
237 	/* Nothing to do for UART driver */
238 	return 0;
239 }
240 
241 /* Reset device */
242 static int hci_uart_flush(struct hci_dev *hdev)
243 {
244 	struct hci_uart *hu  = hci_get_drvdata(hdev);
245 	struct tty_struct *tty = hu->tty;
246 
247 	BT_DBG("hdev %p tty %p", hdev, tty);
248 
249 	if (hu->tx_skb) {
250 		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
251 	}
252 
253 	/* Flush any pending characters in the driver and discipline. */
254 	tty_ldisc_flush(tty);
255 	tty_driver_flush_buffer(tty);
256 
257 	percpu_down_read(&hu->proto_lock);
258 
259 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
260 		hu->proto->flush(hu);
261 
262 	percpu_up_read(&hu->proto_lock);
263 
264 	return 0;
265 }
266 
267 /* Close device */
268 static int hci_uart_close(struct hci_dev *hdev)
269 {
270 	BT_DBG("hdev %p", hdev);
271 
272 	hci_uart_flush(hdev);
273 	hdev->flush = NULL;
274 	return 0;
275 }
276 
277 /* Send frames from HCI layer */
278 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
279 {
280 	struct hci_uart *hu = hci_get_drvdata(hdev);
281 
282 	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
283 	       skb->len);
284 
285 	percpu_down_read(&hu->proto_lock);
286 
287 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
288 		percpu_up_read(&hu->proto_lock);
289 		return -EUNATCH;
290 	}
291 
292 	hu->proto->enqueue(hu, skb);
293 	percpu_up_read(&hu->proto_lock);
294 
295 	hci_uart_tx_wakeup(hu);
296 
297 	return 0;
298 }
299 
300 /* Flow control or un-flow control the device */
301 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
302 {
303 	struct tty_struct *tty = hu->tty;
304 	struct ktermios ktermios;
305 	int status;
306 	unsigned int set = 0;
307 	unsigned int clear = 0;
308 
309 	if (hu->serdev) {
310 		serdev_device_set_flow_control(hu->serdev, !enable);
311 		serdev_device_set_rts(hu->serdev, !enable);
312 		return;
313 	}
314 
315 	if (enable) {
316 		/* Disable hardware flow control */
317 		ktermios = tty->termios;
318 		ktermios.c_cflag &= ~CRTSCTS;
319 		status = tty_set_termios(tty, &ktermios);
320 		BT_DBG("Disabling hardware flow control: %s",
321 		       status ? "failed" : "success");
322 
323 		/* Clear RTS to prevent the device from sending */
324 		/* Most UARTs need OUT2 to enable interrupts */
325 		status = tty->driver->ops->tiocmget(tty);
326 		BT_DBG("Current tiocm 0x%x", status);
327 
328 		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
329 		clear = ~set;
330 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
331 		       TIOCM_OUT2 | TIOCM_LOOP;
332 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
333 			 TIOCM_OUT2 | TIOCM_LOOP;
334 		status = tty->driver->ops->tiocmset(tty, set, clear);
335 		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
336 	} else {
337 		/* Set RTS to allow the device to send again */
338 		status = tty->driver->ops->tiocmget(tty);
339 		BT_DBG("Current tiocm 0x%x", status);
340 
341 		set |= (TIOCM_OUT2 | TIOCM_RTS);
342 		clear = ~set;
343 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
344 		       TIOCM_OUT2 | TIOCM_LOOP;
345 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
346 			 TIOCM_OUT2 | TIOCM_LOOP;
347 		status = tty->driver->ops->tiocmset(tty, set, clear);
348 		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
349 
350 		/* Re-enable hardware flow control */
351 		ktermios = tty->termios;
352 		ktermios.c_cflag |= CRTSCTS;
353 		status = tty_set_termios(tty, &ktermios);
354 		BT_DBG("Enabling hardware flow control: %s",
355 		       status ? "failed" : "success");
356 	}
357 }
358 
359 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
360 			 unsigned int oper_speed)
361 {
362 	hu->init_speed = init_speed;
363 	hu->oper_speed = oper_speed;
364 }
365 
366 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
367 {
368 	struct tty_struct *tty = hu->tty;
369 	struct ktermios ktermios;
370 
371 	ktermios = tty->termios;
372 	ktermios.c_cflag &= ~CBAUD;
373 	tty_termios_encode_baud_rate(&ktermios, speed, speed);
374 
375 	/* tty_set_termios() return not checked as it is always 0 */
376 	tty_set_termios(tty, &ktermios);
377 
378 	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
379 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
380 }
381 
382 static int hci_uart_setup(struct hci_dev *hdev)
383 {
384 	struct hci_uart *hu = hci_get_drvdata(hdev);
385 	struct hci_rp_read_local_version *ver;
386 	struct sk_buff *skb;
387 	unsigned int speed;
388 	int err;
389 
390 	/* Init speed if any */
391 	if (hu->init_speed)
392 		speed = hu->init_speed;
393 	else if (hu->proto->init_speed)
394 		speed = hu->proto->init_speed;
395 	else
396 		speed = 0;
397 
398 	if (speed)
399 		hci_uart_set_baudrate(hu, speed);
400 
401 	/* Operational speed if any */
402 	if (hu->oper_speed)
403 		speed = hu->oper_speed;
404 	else if (hu->proto->oper_speed)
405 		speed = hu->proto->oper_speed;
406 	else
407 		speed = 0;
408 
409 	if (hu->proto->set_baudrate && speed) {
410 		err = hu->proto->set_baudrate(hu, speed);
411 		if (!err)
412 			hci_uart_set_baudrate(hu, speed);
413 	}
414 
415 	if (hu->proto->setup)
416 		return hu->proto->setup(hu);
417 
418 	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
419 		return 0;
420 
421 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
422 			     HCI_INIT_TIMEOUT);
423 	if (IS_ERR(skb)) {
424 		BT_ERR("%s: Reading local version information failed (%ld)",
425 		       hdev->name, PTR_ERR(skb));
426 		return 0;
427 	}
428 
429 	if (skb->len != sizeof(*ver)) {
430 		BT_ERR("%s: Event length mismatch for version information",
431 		       hdev->name);
432 		goto done;
433 	}
434 
435 	ver = (struct hci_rp_read_local_version *)skb->data;
436 
437 	switch (le16_to_cpu(ver->manufacturer)) {
438 #ifdef CONFIG_BT_HCIUART_INTEL
439 	case 2:
440 		hdev->set_bdaddr = btintel_set_bdaddr;
441 		btintel_check_bdaddr(hdev);
442 		break;
443 #endif
444 #ifdef CONFIG_BT_HCIUART_BCM
445 	case 15:
446 		hdev->set_bdaddr = btbcm_set_bdaddr;
447 		btbcm_check_bdaddr(hdev);
448 		break;
449 #endif
450 	default:
451 		break;
452 	}
453 
454 done:
455 	kfree_skb(skb);
456 	return 0;
457 }
458 
459 /* ------ LDISC part ------ */
460 /* hci_uart_tty_open
461  *
462  *     Called when line discipline changed to HCI_UART.
463  *
464  * Arguments:
465  *     tty    pointer to tty info structure
466  * Return Value:
467  *     0 if success, otherwise error code
468  */
469 static int hci_uart_tty_open(struct tty_struct *tty)
470 {
471 	struct hci_uart *hu;
472 
473 	BT_DBG("tty %p", tty);
474 
475 	/* Error if the tty has no write op instead of leaving an exploitable
476 	 * hole
477 	 */
478 	if (tty->ops->write == NULL)
479 		return -EOPNOTSUPP;
480 
481 	hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
482 	if (!hu) {
483 		BT_ERR("Can't allocate control structure");
484 		return -ENFILE;
485 	}
486 
487 	tty->disc_data = hu;
488 	hu->tty = tty;
489 	tty->receive_room = 65536;
490 
491 	/* disable alignment support by default */
492 	hu->alignment = 1;
493 	hu->padding = 0;
494 
495 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
496 	INIT_WORK(&hu->write_work, hci_uart_write_work);
497 
498 	percpu_init_rwsem(&hu->proto_lock);
499 
500 	/* Flush any pending characters in the driver */
501 	tty_driver_flush_buffer(tty);
502 
503 	return 0;
504 }
505 
506 /* hci_uart_tty_close()
507  *
508  *    Called when the line discipline is changed to something
509  *    else, the tty is closed, or the tty detects a hangup.
510  */
511 static void hci_uart_tty_close(struct tty_struct *tty)
512 {
513 	struct hci_uart *hu = tty->disc_data;
514 	struct hci_dev *hdev;
515 
516 	BT_DBG("tty %p", tty);
517 
518 	/* Detach from the tty */
519 	tty->disc_data = NULL;
520 
521 	if (!hu)
522 		return;
523 
524 	hdev = hu->hdev;
525 	if (hdev)
526 		hci_uart_close(hdev);
527 
528 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
529 		percpu_down_write(&hu->proto_lock);
530 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
531 		percpu_up_write(&hu->proto_lock);
532 
533 		cancel_work_sync(&hu->write_work);
534 
535 		if (hdev) {
536 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
537 				hci_unregister_dev(hdev);
538 			hci_free_dev(hdev);
539 		}
540 		hu->proto->close(hu);
541 	}
542 	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
543 
544 	kfree(hu);
545 }
546 
547 /* hci_uart_tty_wakeup()
548  *
549  *    Callback for transmit wakeup. Called when low level
550  *    device driver can accept more send data.
551  *
552  * Arguments:        tty    pointer to associated tty instance data
553  * Return Value:    None
554  */
555 static void hci_uart_tty_wakeup(struct tty_struct *tty)
556 {
557 	struct hci_uart *hu = tty->disc_data;
558 
559 	BT_DBG("");
560 
561 	if (!hu)
562 		return;
563 
564 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
565 
566 	if (tty != hu->tty)
567 		return;
568 
569 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
570 		hci_uart_tx_wakeup(hu);
571 }
572 
573 /* hci_uart_tty_receive()
574  *
575  *     Called by tty low level driver when receive data is
576  *     available.
577  *
578  * Arguments:  tty          pointer to tty isntance data
579  *             data         pointer to received data
580  *             flags        pointer to flags for data
581  *             count        count of received data in bytes
582  *
583  * Return Value:    None
584  */
585 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
586 				 char *flags, int count)
587 {
588 	struct hci_uart *hu = tty->disc_data;
589 
590 	if (!hu || tty != hu->tty)
591 		return;
592 
593 	percpu_down_read(&hu->proto_lock);
594 
595 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
596 		percpu_up_read(&hu->proto_lock);
597 		return;
598 	}
599 
600 	/* It does not need a lock here as it is already protected by a mutex in
601 	 * tty caller
602 	 */
603 	hu->proto->recv(hu, data, count);
604 	percpu_up_read(&hu->proto_lock);
605 
606 	if (hu->hdev)
607 		hu->hdev->stat.byte_rx += count;
608 
609 	tty_unthrottle(tty);
610 }
611 
612 static int hci_uart_register_dev(struct hci_uart *hu)
613 {
614 	struct hci_dev *hdev;
615 
616 	BT_DBG("");
617 
618 	/* Initialize and register HCI device */
619 	hdev = hci_alloc_dev();
620 	if (!hdev) {
621 		BT_ERR("Can't allocate HCI device");
622 		return -ENOMEM;
623 	}
624 
625 	hu->hdev = hdev;
626 
627 	hdev->bus = HCI_UART;
628 	hci_set_drvdata(hdev, hu);
629 
630 	/* Only when vendor specific setup callback is provided, consider
631 	 * the manufacturer information valid. This avoids filling in the
632 	 * value for Ericsson when nothing is specified.
633 	 */
634 	if (hu->proto->setup)
635 		hdev->manufacturer = hu->proto->manufacturer;
636 
637 	hdev->open  = hci_uart_open;
638 	hdev->close = hci_uart_close;
639 	hdev->flush = hci_uart_flush;
640 	hdev->send  = hci_uart_send_frame;
641 	hdev->setup = hci_uart_setup;
642 	SET_HCIDEV_DEV(hdev, hu->tty->dev);
643 
644 	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
645 		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
646 
647 	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
648 		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
649 
650 	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
651 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
652 
653 	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
654 		hdev->dev_type = HCI_AMP;
655 	else
656 		hdev->dev_type = HCI_PRIMARY;
657 
658 	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
659 		return 0;
660 
661 	if (hci_register_dev(hdev) < 0) {
662 		BT_ERR("Can't register HCI device");
663 		hu->hdev = NULL;
664 		hci_free_dev(hdev);
665 		return -ENODEV;
666 	}
667 
668 	set_bit(HCI_UART_REGISTERED, &hu->flags);
669 
670 	return 0;
671 }
672 
673 static int hci_uart_set_proto(struct hci_uart *hu, int id)
674 {
675 	const struct hci_uart_proto *p;
676 	int err;
677 
678 	p = hci_uart_get_proto(id);
679 	if (!p)
680 		return -EPROTONOSUPPORT;
681 
682 	err = p->open(hu);
683 	if (err)
684 		return err;
685 
686 	hu->proto = p;
687 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
688 
689 	err = hci_uart_register_dev(hu);
690 	if (err) {
691 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
692 		p->close(hu);
693 		return err;
694 	}
695 
696 	return 0;
697 }
698 
699 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
700 {
701 	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
702 				    BIT(HCI_UART_RESET_ON_INIT) |
703 				    BIT(HCI_UART_CREATE_AMP) |
704 				    BIT(HCI_UART_INIT_PENDING) |
705 				    BIT(HCI_UART_EXT_CONFIG) |
706 				    BIT(HCI_UART_VND_DETECT);
707 
708 	if (flags & ~valid_flags)
709 		return -EINVAL;
710 
711 	hu->hdev_flags = flags;
712 
713 	return 0;
714 }
715 
716 /* hci_uart_tty_ioctl()
717  *
718  *    Process IOCTL system call for the tty device.
719  *
720  * Arguments:
721  *
722  *    tty        pointer to tty instance data
723  *    file       pointer to open file object for device
724  *    cmd        IOCTL command code
725  *    arg        argument for IOCTL call (cmd dependent)
726  *
727  * Return Value:    Command dependent
728  */
729 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
730 			      unsigned int cmd, unsigned long arg)
731 {
732 	struct hci_uart *hu = tty->disc_data;
733 	int err = 0;
734 
735 	BT_DBG("");
736 
737 	/* Verify the status of the device */
738 	if (!hu)
739 		return -EBADF;
740 
741 	switch (cmd) {
742 	case HCIUARTSETPROTO:
743 		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
744 			err = hci_uart_set_proto(hu, arg);
745 			if (err)
746 				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
747 		} else
748 			err = -EBUSY;
749 		break;
750 
751 	case HCIUARTGETPROTO:
752 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
753 			err = hu->proto->id;
754 		else
755 			err = -EUNATCH;
756 		break;
757 
758 	case HCIUARTGETDEVICE:
759 		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
760 			err = hu->hdev->id;
761 		else
762 			err = -EUNATCH;
763 		break;
764 
765 	case HCIUARTSETFLAGS:
766 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
767 			err = -EBUSY;
768 		else
769 			err = hci_uart_set_flags(hu, arg);
770 		break;
771 
772 	case HCIUARTGETFLAGS:
773 		err = hu->hdev_flags;
774 		break;
775 
776 	default:
777 		err = n_tty_ioctl_helper(tty, file, cmd, arg);
778 		break;
779 	}
780 
781 	return err;
782 }
783 
784 /*
785  * We don't provide read/write/poll interface for user space.
786  */
787 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
788 				 unsigned char __user *buf, size_t nr)
789 {
790 	return 0;
791 }
792 
793 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
794 				  const unsigned char *data, size_t count)
795 {
796 	return 0;
797 }
798 
799 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
800 				      struct file *filp, poll_table *wait)
801 {
802 	return 0;
803 }
804 
805 static int __init hci_uart_init(void)
806 {
807 	static struct tty_ldisc_ops hci_uart_ldisc;
808 	int err;
809 
810 	BT_INFO("HCI UART driver ver %s", VERSION);
811 
812 	/* Register the tty discipline */
813 
814 	memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
815 	hci_uart_ldisc.magic		= TTY_LDISC_MAGIC;
816 	hci_uart_ldisc.name		= "n_hci";
817 	hci_uart_ldisc.open		= hci_uart_tty_open;
818 	hci_uart_ldisc.close		= hci_uart_tty_close;
819 	hci_uart_ldisc.read		= hci_uart_tty_read;
820 	hci_uart_ldisc.write		= hci_uart_tty_write;
821 	hci_uart_ldisc.ioctl		= hci_uart_tty_ioctl;
822 	hci_uart_ldisc.poll		= hci_uart_tty_poll;
823 	hci_uart_ldisc.receive_buf	= hci_uart_tty_receive;
824 	hci_uart_ldisc.write_wakeup	= hci_uart_tty_wakeup;
825 	hci_uart_ldisc.owner		= THIS_MODULE;
826 
827 	err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
828 	if (err) {
829 		BT_ERR("HCI line discipline registration failed. (%d)", err);
830 		return err;
831 	}
832 
833 #ifdef CONFIG_BT_HCIUART_H4
834 	h4_init();
835 #endif
836 #ifdef CONFIG_BT_HCIUART_BCSP
837 	bcsp_init();
838 #endif
839 #ifdef CONFIG_BT_HCIUART_LL
840 	ll_init();
841 #endif
842 #ifdef CONFIG_BT_HCIUART_ATH3K
843 	ath_init();
844 #endif
845 #ifdef CONFIG_BT_HCIUART_3WIRE
846 	h5_init();
847 #endif
848 #ifdef CONFIG_BT_HCIUART_INTEL
849 	intel_init();
850 #endif
851 #ifdef CONFIG_BT_HCIUART_BCM
852 	bcm_init();
853 #endif
854 #ifdef CONFIG_BT_HCIUART_QCA
855 	qca_init();
856 #endif
857 #ifdef CONFIG_BT_HCIUART_AG6XX
858 	ag6xx_init();
859 #endif
860 #ifdef CONFIG_BT_HCIUART_MRVL
861 	mrvl_init();
862 #endif
863 
864 	return 0;
865 }
866 
867 static void __exit hci_uart_exit(void)
868 {
869 	int err;
870 
871 #ifdef CONFIG_BT_HCIUART_H4
872 	h4_deinit();
873 #endif
874 #ifdef CONFIG_BT_HCIUART_BCSP
875 	bcsp_deinit();
876 #endif
877 #ifdef CONFIG_BT_HCIUART_LL
878 	ll_deinit();
879 #endif
880 #ifdef CONFIG_BT_HCIUART_ATH3K
881 	ath_deinit();
882 #endif
883 #ifdef CONFIG_BT_HCIUART_3WIRE
884 	h5_deinit();
885 #endif
886 #ifdef CONFIG_BT_HCIUART_INTEL
887 	intel_deinit();
888 #endif
889 #ifdef CONFIG_BT_HCIUART_BCM
890 	bcm_deinit();
891 #endif
892 #ifdef CONFIG_BT_HCIUART_QCA
893 	qca_deinit();
894 #endif
895 #ifdef CONFIG_BT_HCIUART_AG6XX
896 	ag6xx_deinit();
897 #endif
898 #ifdef CONFIG_BT_HCIUART_MRVL
899 	mrvl_deinit();
900 #endif
901 
902 	/* Release tty registration of line discipline */
903 	err = tty_unregister_ldisc(N_HCI);
904 	if (err)
905 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
906 }
907 
908 module_init(hci_uart_init);
909 module_exit(hci_uart_exit);
910 
911 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
912 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
913 MODULE_VERSION(VERSION);
914 MODULE_LICENSE("GPL");
915 MODULE_ALIAS_LDISC(N_HCI);
916