xref: /linux/drivers/bluetooth/hci_ldisc.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  *  Bluetooth HCI UART driver
5  *
6  *  Copyright (C) 2000-2001  Qualcomm Incorporated
7  *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
8  *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
9  */
10 
11 #include <linux/module.h>
12 
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/types.h>
16 #include <linux/fcntl.h>
17 #include <linux/interrupt.h>
18 #include <linux/ptrace.h>
19 #include <linux/poll.h>
20 
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/signal.h>
26 #include <linux/ioctl.h>
27 #include <linux/skbuff.h>
28 #include <linux/firmware.h>
29 #include <linux/serdev.h>
30 
31 #include <net/bluetooth/bluetooth.h>
32 #include <net/bluetooth/hci_core.h>
33 
34 #include "btintel.h"
35 #include "btbcm.h"
36 #include "hci_uart.h"
37 
38 #define VERSION "2.3"
39 
40 static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
41 
42 int hci_uart_register_proto(const struct hci_uart_proto *p)
43 {
44 	if (p->id >= HCI_UART_MAX_PROTO)
45 		return -EINVAL;
46 
47 	if (hup[p->id])
48 		return -EEXIST;
49 
50 	hup[p->id] = p;
51 
52 	BT_INFO("HCI UART protocol %s registered", p->name);
53 
54 	return 0;
55 }
56 
57 int hci_uart_unregister_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 -EINVAL;
64 
65 	hup[p->id] = NULL;
66 
67 	return 0;
68 }
69 
70 static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
71 {
72 	if (id >= HCI_UART_MAX_PROTO)
73 		return NULL;
74 
75 	return hup[id];
76 }
77 
78 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
79 {
80 	struct hci_dev *hdev = hu->hdev;
81 
82 	/* Update HCI stat counters */
83 	switch (pkt_type) {
84 	case HCI_COMMAND_PKT:
85 		hdev->stat.cmd_tx++;
86 		break;
87 
88 	case HCI_ACLDATA_PKT:
89 		hdev->stat.acl_tx++;
90 		break;
91 
92 	case HCI_SCODATA_PKT:
93 		hdev->stat.sco_tx++;
94 		break;
95 	}
96 }
97 
98 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
99 {
100 	struct sk_buff *skb = hu->tx_skb;
101 
102 	if (!skb) {
103 		percpu_down_read(&hu->proto_lock);
104 
105 		if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
106 			skb = hu->proto->dequeue(hu);
107 
108 		percpu_up_read(&hu->proto_lock);
109 	} else {
110 		hu->tx_skb = NULL;
111 	}
112 
113 	return skb;
114 }
115 
116 int hci_uart_tx_wakeup(struct hci_uart *hu)
117 {
118 	/* This may be called in an IRQ context, so we can't sleep. Therefore
119 	 * we try to acquire the lock only, and if that fails we assume the
120 	 * tty is being closed because that is the only time the write lock is
121 	 * acquired. If, however, at some point in the future the write lock
122 	 * is also acquired in other situations, then this must be revisited.
123 	 */
124 	if (!percpu_down_read_trylock(&hu->proto_lock))
125 		return 0;
126 
127 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
128 		goto no_schedule;
129 
130 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
131 		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
132 		goto no_schedule;
133 	}
134 
135 	BT_DBG("");
136 
137 	schedule_work(&hu->write_work);
138 
139 no_schedule:
140 	percpu_up_read(&hu->proto_lock);
141 
142 	return 0;
143 }
144 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
145 
146 static void hci_uart_write_work(struct work_struct *work)
147 {
148 	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
149 	struct tty_struct *tty = hu->tty;
150 	struct hci_dev *hdev = hu->hdev;
151 	struct sk_buff *skb;
152 
153 	/* REVISIT: should we cope with bad skbs or ->write() returning
154 	 * and error value ?
155 	 */
156 
157 restart:
158 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
159 
160 	while ((skb = hci_uart_dequeue(hu))) {
161 		int len;
162 
163 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
164 		len = tty->ops->write(tty, skb->data, skb->len);
165 		hdev->stat.byte_tx += len;
166 
167 		skb_pull(skb, len);
168 		if (skb->len) {
169 			hu->tx_skb = skb;
170 			break;
171 		}
172 
173 		hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
174 		kfree_skb(skb);
175 	}
176 
177 	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
178 		goto restart;
179 
180 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
181 	wake_up_bit(&hu->tx_state, HCI_UART_SENDING);
182 }
183 
184 void hci_uart_init_work(struct work_struct *work)
185 {
186 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
187 	int err;
188 	struct hci_dev *hdev;
189 
190 	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
191 		return;
192 
193 	err = hci_register_dev(hu->hdev);
194 	if (err < 0) {
195 		BT_ERR("Can't register HCI device");
196 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
197 		hu->proto->close(hu);
198 		hdev = hu->hdev;
199 		hu->hdev = NULL;
200 		hci_free_dev(hdev);
201 		return;
202 	}
203 
204 	set_bit(HCI_UART_REGISTERED, &hu->flags);
205 }
206 
207 int hci_uart_init_ready(struct hci_uart *hu)
208 {
209 	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
210 		return -EALREADY;
211 
212 	schedule_work(&hu->init_ready);
213 
214 	return 0;
215 }
216 
217 int hci_uart_wait_until_sent(struct hci_uart *hu)
218 {
219 	return wait_on_bit_timeout(&hu->tx_state, HCI_UART_SENDING,
220 				   TASK_INTERRUPTIBLE,
221 				   msecs_to_jiffies(2000));
222 }
223 
224 /* ------- Interface to HCI layer ------ */
225 /* Reset device */
226 static int hci_uart_flush(struct hci_dev *hdev)
227 {
228 	struct hci_uart *hu  = hci_get_drvdata(hdev);
229 	struct tty_struct *tty = hu->tty;
230 
231 	BT_DBG("hdev %p tty %p", hdev, tty);
232 
233 	if (hu->tx_skb) {
234 		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
235 	}
236 
237 	/* Flush any pending characters in the driver and discipline. */
238 	tty_ldisc_flush(tty);
239 	tty_driver_flush_buffer(tty);
240 
241 	percpu_down_read(&hu->proto_lock);
242 
243 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
244 		hu->proto->flush(hu);
245 
246 	percpu_up_read(&hu->proto_lock);
247 
248 	return 0;
249 }
250 
251 /* Initialize device */
252 static int hci_uart_open(struct hci_dev *hdev)
253 {
254 	BT_DBG("%s %p", hdev->name, hdev);
255 
256 	/* Undo clearing this from hci_uart_close() */
257 	hdev->flush = hci_uart_flush;
258 
259 	return 0;
260 }
261 
262 /* Close device */
263 static int hci_uart_close(struct hci_dev *hdev)
264 {
265 	BT_DBG("hdev %p", hdev);
266 
267 	hci_uart_flush(hdev);
268 	hdev->flush = NULL;
269 	return 0;
270 }
271 
272 /* Send frames from HCI layer */
273 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
274 {
275 	struct hci_uart *hu = hci_get_drvdata(hdev);
276 
277 	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
278 	       skb->len);
279 
280 	percpu_down_read(&hu->proto_lock);
281 
282 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
283 		percpu_up_read(&hu->proto_lock);
284 		return -EUNATCH;
285 	}
286 
287 	hu->proto->enqueue(hu, skb);
288 	percpu_up_read(&hu->proto_lock);
289 
290 	hci_uart_tx_wakeup(hu);
291 
292 	return 0;
293 }
294 
295 /* Check the underlying device or tty has flow control support */
296 bool hci_uart_has_flow_control(struct hci_uart *hu)
297 {
298 	/* serdev nodes check if the needed operations are present */
299 	if (hu->serdev)
300 		return true;
301 
302 	if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
303 		return true;
304 
305 	return false;
306 }
307 
308 /* Flow control or un-flow control the device */
309 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
310 {
311 	struct tty_struct *tty = hu->tty;
312 	struct ktermios ktermios;
313 	int status;
314 	unsigned int set = 0;
315 	unsigned int clear = 0;
316 
317 	if (hu->serdev) {
318 		serdev_device_set_flow_control(hu->serdev, !enable);
319 		serdev_device_set_rts(hu->serdev, !enable);
320 		return;
321 	}
322 
323 	if (enable) {
324 		/* Disable hardware flow control */
325 		ktermios = tty->termios;
326 		ktermios.c_cflag &= ~CRTSCTS;
327 		status = tty_set_termios(tty, &ktermios);
328 		BT_DBG("Disabling hardware flow control: %s",
329 		       status ? "failed" : "success");
330 
331 		/* Clear RTS to prevent the device from sending */
332 		/* Most UARTs need OUT2 to enable interrupts */
333 		status = tty->driver->ops->tiocmget(tty);
334 		BT_DBG("Current tiocm 0x%x", status);
335 
336 		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
337 		clear = ~set;
338 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
339 		       TIOCM_OUT2 | TIOCM_LOOP;
340 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
341 			 TIOCM_OUT2 | TIOCM_LOOP;
342 		status = tty->driver->ops->tiocmset(tty, set, clear);
343 		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
344 	} else {
345 		/* Set RTS to allow the device to send again */
346 		status = tty->driver->ops->tiocmget(tty);
347 		BT_DBG("Current tiocm 0x%x", status);
348 
349 		set |= (TIOCM_OUT2 | TIOCM_RTS);
350 		clear = ~set;
351 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
352 		       TIOCM_OUT2 | TIOCM_LOOP;
353 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
354 			 TIOCM_OUT2 | TIOCM_LOOP;
355 		status = tty->driver->ops->tiocmset(tty, set, clear);
356 		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
357 
358 		/* Re-enable hardware flow control */
359 		ktermios = tty->termios;
360 		ktermios.c_cflag |= CRTSCTS;
361 		status = tty_set_termios(tty, &ktermios);
362 		BT_DBG("Enabling hardware flow control: %s",
363 		       status ? "failed" : "success");
364 	}
365 }
366 
367 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
368 			 unsigned int oper_speed)
369 {
370 	hu->init_speed = init_speed;
371 	hu->oper_speed = oper_speed;
372 }
373 
374 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
375 {
376 	struct tty_struct *tty = hu->tty;
377 	struct ktermios ktermios;
378 
379 	ktermios = tty->termios;
380 	ktermios.c_cflag &= ~CBAUD;
381 	tty_termios_encode_baud_rate(&ktermios, speed, speed);
382 
383 	/* tty_set_termios() return not checked as it is always 0 */
384 	tty_set_termios(tty, &ktermios);
385 
386 	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
387 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
388 }
389 
390 static int hci_uart_setup(struct hci_dev *hdev)
391 {
392 	struct hci_uart *hu = hci_get_drvdata(hdev);
393 	struct hci_rp_read_local_version *ver;
394 	struct sk_buff *skb;
395 	unsigned int speed;
396 	int err;
397 
398 	/* Init speed if any */
399 	if (hu->init_speed)
400 		speed = hu->init_speed;
401 	else if (hu->proto->init_speed)
402 		speed = hu->proto->init_speed;
403 	else
404 		speed = 0;
405 
406 	if (speed)
407 		hci_uart_set_baudrate(hu, speed);
408 
409 	/* Operational speed if any */
410 	if (hu->oper_speed)
411 		speed = hu->oper_speed;
412 	else if (hu->proto->oper_speed)
413 		speed = hu->proto->oper_speed;
414 	else
415 		speed = 0;
416 
417 	if (hu->proto->set_baudrate && speed) {
418 		err = hu->proto->set_baudrate(hu, speed);
419 		if (!err)
420 			hci_uart_set_baudrate(hu, speed);
421 	}
422 
423 	if (hu->proto->setup)
424 		return hu->proto->setup(hu);
425 
426 	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
427 		return 0;
428 
429 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
430 			     HCI_INIT_TIMEOUT);
431 	if (IS_ERR(skb)) {
432 		BT_ERR("%s: Reading local version information failed (%ld)",
433 		       hdev->name, PTR_ERR(skb));
434 		return 0;
435 	}
436 
437 	if (skb->len != sizeof(*ver)) {
438 		BT_ERR("%s: Event length mismatch for version information",
439 		       hdev->name);
440 		goto done;
441 	}
442 
443 	ver = (struct hci_rp_read_local_version *)skb->data;
444 
445 	switch (le16_to_cpu(ver->manufacturer)) {
446 #ifdef CONFIG_BT_HCIUART_INTEL
447 	case 2:
448 		hdev->set_bdaddr = btintel_set_bdaddr;
449 		btintel_check_bdaddr(hdev);
450 		break;
451 #endif
452 #ifdef CONFIG_BT_HCIUART_BCM
453 	case 15:
454 		hdev->set_bdaddr = btbcm_set_bdaddr;
455 		btbcm_check_bdaddr(hdev);
456 		break;
457 #endif
458 	default:
459 		break;
460 	}
461 
462 done:
463 	kfree_skb(skb);
464 	return 0;
465 }
466 
467 /* ------ LDISC part ------ */
468 /* hci_uart_tty_open
469  *
470  *     Called when line discipline changed to HCI_UART.
471  *
472  * Arguments:
473  *     tty    pointer to tty info structure
474  * Return Value:
475  *     0 if success, otherwise error code
476  */
477 static int hci_uart_tty_open(struct tty_struct *tty)
478 {
479 	struct hci_uart *hu;
480 
481 	BT_DBG("tty %p", tty);
482 
483 	/* Error if the tty has no write op instead of leaving an exploitable
484 	 * hole
485 	 */
486 	if (tty->ops->write == NULL)
487 		return -EOPNOTSUPP;
488 
489 	hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
490 	if (!hu) {
491 		BT_ERR("Can't allocate control structure");
492 		return -ENFILE;
493 	}
494 
495 	tty->disc_data = hu;
496 	hu->tty = tty;
497 	tty->receive_room = 65536;
498 
499 	/* disable alignment support by default */
500 	hu->alignment = 1;
501 	hu->padding = 0;
502 
503 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
504 	INIT_WORK(&hu->write_work, hci_uart_write_work);
505 
506 	percpu_init_rwsem(&hu->proto_lock);
507 
508 	/* Flush any pending characters in the driver */
509 	tty_driver_flush_buffer(tty);
510 
511 	return 0;
512 }
513 
514 /* hci_uart_tty_close()
515  *
516  *    Called when the line discipline is changed to something
517  *    else, the tty is closed, or the tty detects a hangup.
518  */
519 static void hci_uart_tty_close(struct tty_struct *tty)
520 {
521 	struct hci_uart *hu = tty->disc_data;
522 	struct hci_dev *hdev;
523 
524 	BT_DBG("tty %p", tty);
525 
526 	/* Detach from the tty */
527 	tty->disc_data = NULL;
528 
529 	if (!hu)
530 		return;
531 
532 	hdev = hu->hdev;
533 	if (hdev)
534 		hci_uart_close(hdev);
535 
536 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
537 		percpu_down_write(&hu->proto_lock);
538 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
539 		percpu_up_write(&hu->proto_lock);
540 
541 		cancel_work_sync(&hu->write_work);
542 
543 		if (hdev) {
544 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
545 				hci_unregister_dev(hdev);
546 			hci_free_dev(hdev);
547 		}
548 		hu->proto->close(hu);
549 	}
550 	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
551 
552 	percpu_free_rwsem(&hu->proto_lock);
553 
554 	kfree(hu);
555 }
556 
557 /* hci_uart_tty_wakeup()
558  *
559  *    Callback for transmit wakeup. Called when low level
560  *    device driver can accept more send data.
561  *
562  * Arguments:        tty    pointer to associated tty instance data
563  * Return Value:    None
564  */
565 static void hci_uart_tty_wakeup(struct tty_struct *tty)
566 {
567 	struct hci_uart *hu = tty->disc_data;
568 
569 	BT_DBG("");
570 
571 	if (!hu)
572 		return;
573 
574 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
575 
576 	if (tty != hu->tty)
577 		return;
578 
579 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
580 		hci_uart_tx_wakeup(hu);
581 }
582 
583 /* hci_uart_tty_receive()
584  *
585  *     Called by tty low level driver when receive data is
586  *     available.
587  *
588  * Arguments:  tty          pointer to tty isntance data
589  *             data         pointer to received data
590  *             flags        pointer to flags for data
591  *             count        count of received data in bytes
592  *
593  * Return Value:    None
594  */
595 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
596 				 char *flags, int count)
597 {
598 	struct hci_uart *hu = tty->disc_data;
599 
600 	if (!hu || tty != hu->tty)
601 		return;
602 
603 	percpu_down_read(&hu->proto_lock);
604 
605 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
606 		percpu_up_read(&hu->proto_lock);
607 		return;
608 	}
609 
610 	/* It does not need a lock here as it is already protected by a mutex in
611 	 * tty caller
612 	 */
613 	hu->proto->recv(hu, data, count);
614 	percpu_up_read(&hu->proto_lock);
615 
616 	if (hu->hdev)
617 		hu->hdev->stat.byte_rx += count;
618 
619 	tty_unthrottle(tty);
620 }
621 
622 static int hci_uart_register_dev(struct hci_uart *hu)
623 {
624 	struct hci_dev *hdev;
625 	int err;
626 
627 	BT_DBG("");
628 
629 	/* Initialize and register HCI device */
630 	hdev = hci_alloc_dev();
631 	if (!hdev) {
632 		BT_ERR("Can't allocate HCI device");
633 		return -ENOMEM;
634 	}
635 
636 	hu->hdev = hdev;
637 
638 	hdev->bus = HCI_UART;
639 	hci_set_drvdata(hdev, hu);
640 
641 	/* Only when vendor specific setup callback is provided, consider
642 	 * the manufacturer information valid. This avoids filling in the
643 	 * value for Ericsson when nothing is specified.
644 	 */
645 	if (hu->proto->setup)
646 		hdev->manufacturer = hu->proto->manufacturer;
647 
648 	hdev->open  = hci_uart_open;
649 	hdev->close = hci_uart_close;
650 	hdev->flush = hci_uart_flush;
651 	hdev->send  = hci_uart_send_frame;
652 	hdev->setup = hci_uart_setup;
653 	SET_HCIDEV_DEV(hdev, hu->tty->dev);
654 
655 	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
656 		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
657 
658 	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
659 		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
660 
661 	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
662 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
663 
664 	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
665 		hdev->dev_type = HCI_AMP;
666 	else
667 		hdev->dev_type = HCI_PRIMARY;
668 
669 	/* Only call open() for the protocol after hdev is fully initialized as
670 	 * open() (or a timer/workqueue it starts) may attempt to reference it.
671 	 */
672 	err = hu->proto->open(hu);
673 	if (err) {
674 		hu->hdev = NULL;
675 		hci_free_dev(hdev);
676 		return err;
677 	}
678 
679 	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
680 		return 0;
681 
682 	if (hci_register_dev(hdev) < 0) {
683 		BT_ERR("Can't register HCI device");
684 		hu->proto->close(hu);
685 		hu->hdev = NULL;
686 		hci_free_dev(hdev);
687 		return -ENODEV;
688 	}
689 
690 	set_bit(HCI_UART_REGISTERED, &hu->flags);
691 
692 	return 0;
693 }
694 
695 static int hci_uart_set_proto(struct hci_uart *hu, int id)
696 {
697 	const struct hci_uart_proto *p;
698 	int err;
699 
700 	p = hci_uart_get_proto(id);
701 	if (!p)
702 		return -EPROTONOSUPPORT;
703 
704 	hu->proto = p;
705 
706 	err = hci_uart_register_dev(hu);
707 	if (err) {
708 		return err;
709 	}
710 
711 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
712 	return 0;
713 }
714 
715 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
716 {
717 	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
718 				    BIT(HCI_UART_RESET_ON_INIT) |
719 				    BIT(HCI_UART_CREATE_AMP) |
720 				    BIT(HCI_UART_INIT_PENDING) |
721 				    BIT(HCI_UART_EXT_CONFIG) |
722 				    BIT(HCI_UART_VND_DETECT);
723 
724 	if (flags & ~valid_flags)
725 		return -EINVAL;
726 
727 	hu->hdev_flags = flags;
728 
729 	return 0;
730 }
731 
732 /* hci_uart_tty_ioctl()
733  *
734  *    Process IOCTL system call for the tty device.
735  *
736  * Arguments:
737  *
738  *    tty        pointer to tty instance data
739  *    file       pointer to open file object for device
740  *    cmd        IOCTL command code
741  *    arg        argument for IOCTL call (cmd dependent)
742  *
743  * Return Value:    Command dependent
744  */
745 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
746 			      unsigned int cmd, unsigned long arg)
747 {
748 	struct hci_uart *hu = tty->disc_data;
749 	int err = 0;
750 
751 	BT_DBG("");
752 
753 	/* Verify the status of the device */
754 	if (!hu)
755 		return -EBADF;
756 
757 	switch (cmd) {
758 	case HCIUARTSETPROTO:
759 		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
760 			err = hci_uart_set_proto(hu, arg);
761 			if (err)
762 				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
763 		} else
764 			err = -EBUSY;
765 		break;
766 
767 	case HCIUARTGETPROTO:
768 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
769 			err = hu->proto->id;
770 		else
771 			err = -EUNATCH;
772 		break;
773 
774 	case HCIUARTGETDEVICE:
775 		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
776 			err = hu->hdev->id;
777 		else
778 			err = -EUNATCH;
779 		break;
780 
781 	case HCIUARTSETFLAGS:
782 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
783 			err = -EBUSY;
784 		else
785 			err = hci_uart_set_flags(hu, arg);
786 		break;
787 
788 	case HCIUARTGETFLAGS:
789 		err = hu->hdev_flags;
790 		break;
791 
792 	default:
793 		err = n_tty_ioctl_helper(tty, file, cmd, arg);
794 		break;
795 	}
796 
797 	return err;
798 }
799 
800 /*
801  * We don't provide read/write/poll interface for user space.
802  */
803 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
804 				 unsigned char __user *buf, size_t nr)
805 {
806 	return 0;
807 }
808 
809 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
810 				  const unsigned char *data, size_t count)
811 {
812 	return 0;
813 }
814 
815 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
816 				      struct file *filp, poll_table *wait)
817 {
818 	return 0;
819 }
820 
821 static int __init hci_uart_init(void)
822 {
823 	static struct tty_ldisc_ops hci_uart_ldisc;
824 	int err;
825 
826 	BT_INFO("HCI UART driver ver %s", VERSION);
827 
828 	/* Register the tty discipline */
829 
830 	memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
831 	hci_uart_ldisc.magic		= TTY_LDISC_MAGIC;
832 	hci_uart_ldisc.name		= "n_hci";
833 	hci_uart_ldisc.open		= hci_uart_tty_open;
834 	hci_uart_ldisc.close		= hci_uart_tty_close;
835 	hci_uart_ldisc.read		= hci_uart_tty_read;
836 	hci_uart_ldisc.write		= hci_uart_tty_write;
837 	hci_uart_ldisc.ioctl		= hci_uart_tty_ioctl;
838 	hci_uart_ldisc.compat_ioctl	= hci_uart_tty_ioctl;
839 	hci_uart_ldisc.poll		= hci_uart_tty_poll;
840 	hci_uart_ldisc.receive_buf	= hci_uart_tty_receive;
841 	hci_uart_ldisc.write_wakeup	= hci_uart_tty_wakeup;
842 	hci_uart_ldisc.owner		= THIS_MODULE;
843 
844 	err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
845 	if (err) {
846 		BT_ERR("HCI line discipline registration failed. (%d)", err);
847 		return err;
848 	}
849 
850 #ifdef CONFIG_BT_HCIUART_H4
851 	h4_init();
852 #endif
853 #ifdef CONFIG_BT_HCIUART_BCSP
854 	bcsp_init();
855 #endif
856 #ifdef CONFIG_BT_HCIUART_LL
857 	ll_init();
858 #endif
859 #ifdef CONFIG_BT_HCIUART_ATH3K
860 	ath_init();
861 #endif
862 #ifdef CONFIG_BT_HCIUART_3WIRE
863 	h5_init();
864 #endif
865 #ifdef CONFIG_BT_HCIUART_INTEL
866 	intel_init();
867 #endif
868 #ifdef CONFIG_BT_HCIUART_BCM
869 	bcm_init();
870 #endif
871 #ifdef CONFIG_BT_HCIUART_QCA
872 	qca_init();
873 #endif
874 #ifdef CONFIG_BT_HCIUART_AG6XX
875 	ag6xx_init();
876 #endif
877 #ifdef CONFIG_BT_HCIUART_MRVL
878 	mrvl_init();
879 #endif
880 
881 	return 0;
882 }
883 
884 static void __exit hci_uart_exit(void)
885 {
886 	int err;
887 
888 #ifdef CONFIG_BT_HCIUART_H4
889 	h4_deinit();
890 #endif
891 #ifdef CONFIG_BT_HCIUART_BCSP
892 	bcsp_deinit();
893 #endif
894 #ifdef CONFIG_BT_HCIUART_LL
895 	ll_deinit();
896 #endif
897 #ifdef CONFIG_BT_HCIUART_ATH3K
898 	ath_deinit();
899 #endif
900 #ifdef CONFIG_BT_HCIUART_3WIRE
901 	h5_deinit();
902 #endif
903 #ifdef CONFIG_BT_HCIUART_INTEL
904 	intel_deinit();
905 #endif
906 #ifdef CONFIG_BT_HCIUART_BCM
907 	bcm_deinit();
908 #endif
909 #ifdef CONFIG_BT_HCIUART_QCA
910 	qca_deinit();
911 #endif
912 #ifdef CONFIG_BT_HCIUART_AG6XX
913 	ag6xx_deinit();
914 #endif
915 #ifdef CONFIG_BT_HCIUART_MRVL
916 	mrvl_deinit();
917 #endif
918 
919 	/* Release tty registration of line discipline */
920 	err = tty_unregister_ldisc(N_HCI);
921 	if (err)
922 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
923 }
924 
925 module_init(hci_uart_init);
926 module_exit(hci_uart_exit);
927 
928 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
929 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
930 MODULE_VERSION(VERSION);
931 MODULE_LICENSE("GPL");
932 MODULE_ALIAS_LDISC(N_HCI);
933