xref: /OK3568_Linux_fs/kernel/drivers/bluetooth/hci_ldisc.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
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 
hci_uart_register_proto(const struct hci_uart_proto * p)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 
hci_uart_unregister_proto(const struct hci_uart_proto * p)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 
hci_uart_get_proto(unsigned int id)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 
hci_uart_tx_complete(struct hci_uart * hu,int pkt_type)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 
hci_uart_dequeue(struct hci_uart * hu)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 
hci_uart_tx_wakeup(struct hci_uart * hu)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 	set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
131 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state))
132 		goto no_schedule;
133 
134 	BT_DBG("");
135 
136 	schedule_work(&hu->write_work);
137 
138 no_schedule:
139 	percpu_up_read(&hu->proto_lock);
140 
141 	return 0;
142 }
143 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
144 
hci_uart_write_work(struct work_struct * work)145 static void hci_uart_write_work(struct work_struct *work)
146 {
147 	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
148 	struct tty_struct *tty = hu->tty;
149 	struct hci_dev *hdev = hu->hdev;
150 	struct sk_buff *skb;
151 
152 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
153 		clear_bit(HCI_UART_SENDING, &hu->tx_state);
154 		return;
155 	}
156 
157 	/* REVISIT: should we cope with bad skbs or ->write() returning
158 	 * and error value ?
159 	 */
160 
161 restart:
162 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
163 
164 	while ((skb = hci_uart_dequeue(hu))) {
165 		int len;
166 
167 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
168 		len = tty->ops->write(tty, skb->data, skb->len);
169 		hdev->stat.byte_tx += len;
170 
171 		skb_pull(skb, len);
172 		if (skb->len) {
173 			hu->tx_skb = skb;
174 			break;
175 		}
176 
177 		hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
178 		kfree_skb(skb);
179 	}
180 
181 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
182 	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
183 		goto restart;
184 
185 	wake_up_bit(&hu->tx_state, HCI_UART_SENDING);
186 }
187 
hci_uart_init_work(struct work_struct * work)188 void hci_uart_init_work(struct work_struct *work)
189 {
190 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
191 	int err;
192 	struct hci_dev *hdev;
193 
194 	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
195 		return;
196 
197 	err = hci_register_dev(hu->hdev);
198 	if (err < 0) {
199 		BT_ERR("Can't register HCI device");
200 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
201 		hu->proto->close(hu);
202 		hdev = hu->hdev;
203 		hu->hdev = NULL;
204 		hci_free_dev(hdev);
205 		return;
206 	}
207 
208 	set_bit(HCI_UART_REGISTERED, &hu->flags);
209 }
210 
hci_uart_init_ready(struct hci_uart * hu)211 int hci_uart_init_ready(struct hci_uart *hu)
212 {
213 	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
214 		return -EALREADY;
215 
216 	schedule_work(&hu->init_ready);
217 
218 	return 0;
219 }
220 
hci_uart_wait_until_sent(struct hci_uart * hu)221 int hci_uart_wait_until_sent(struct hci_uart *hu)
222 {
223 	return wait_on_bit_timeout(&hu->tx_state, HCI_UART_SENDING,
224 				   TASK_INTERRUPTIBLE,
225 				   msecs_to_jiffies(2000));
226 }
227 
228 /* ------- Interface to HCI layer ------ */
229 /* Reset device */
hci_uart_flush(struct hci_dev * hdev)230 static int hci_uart_flush(struct hci_dev *hdev)
231 {
232 	struct hci_uart *hu  = hci_get_drvdata(hdev);
233 	struct tty_struct *tty = hu->tty;
234 
235 	BT_DBG("hdev %p tty %p", hdev, tty);
236 
237 	if (hu->tx_skb) {
238 		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
239 	}
240 
241 	/* Flush any pending characters in the driver and discipline. */
242 	tty_ldisc_flush(tty);
243 	tty_driver_flush_buffer(tty);
244 
245 	percpu_down_read(&hu->proto_lock);
246 
247 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
248 		hu->proto->flush(hu);
249 
250 	percpu_up_read(&hu->proto_lock);
251 
252 	return 0;
253 }
254 
255 /* Initialize device */
hci_uart_open(struct hci_dev * hdev)256 static int hci_uart_open(struct hci_dev *hdev)
257 {
258 	BT_DBG("%s %p", hdev->name, hdev);
259 
260 	/* Undo clearing this from hci_uart_close() */
261 	hdev->flush = hci_uart_flush;
262 
263 	return 0;
264 }
265 
266 /* Close device */
hci_uart_close(struct hci_dev * hdev)267 static int hci_uart_close(struct hci_dev *hdev)
268 {
269 	BT_DBG("hdev %p", hdev);
270 
271 	hci_uart_flush(hdev);
272 	hdev->flush = NULL;
273 	return 0;
274 }
275 
276 /* Send frames from HCI layer */
hci_uart_send_frame(struct hci_dev * hdev,struct sk_buff * skb)277 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
278 {
279 	struct hci_uart *hu = hci_get_drvdata(hdev);
280 
281 	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
282 	       skb->len);
283 
284 	percpu_down_read(&hu->proto_lock);
285 
286 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
287 		percpu_up_read(&hu->proto_lock);
288 		return -EUNATCH;
289 	}
290 
291 	hu->proto->enqueue(hu, skb);
292 	percpu_up_read(&hu->proto_lock);
293 
294 	hci_uart_tx_wakeup(hu);
295 
296 	return 0;
297 }
298 
299 /* Check the underlying device or tty has flow control support */
hci_uart_has_flow_control(struct hci_uart * hu)300 bool hci_uart_has_flow_control(struct hci_uart *hu)
301 {
302 	/* serdev nodes check if the needed operations are present */
303 	if (hu->serdev)
304 		return true;
305 
306 	if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
307 		return true;
308 
309 	return false;
310 }
311 
312 /* Flow control or un-flow control the device */
hci_uart_set_flow_control(struct hci_uart * hu,bool enable)313 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
314 {
315 	struct tty_struct *tty = hu->tty;
316 	struct ktermios ktermios;
317 	int status;
318 	unsigned int set = 0;
319 	unsigned int clear = 0;
320 
321 	if (hu->serdev) {
322 		serdev_device_set_flow_control(hu->serdev, !enable);
323 		serdev_device_set_rts(hu->serdev, !enable);
324 		return;
325 	}
326 
327 	if (enable) {
328 		/* Disable hardware flow control */
329 		ktermios = tty->termios;
330 		ktermios.c_cflag &= ~CRTSCTS;
331 		status = tty_set_termios(tty, &ktermios);
332 		BT_DBG("Disabling hardware flow control: %s",
333 		       status ? "failed" : "success");
334 
335 		/* Clear RTS to prevent the device from sending */
336 		/* Most UARTs need OUT2 to enable interrupts */
337 		status = tty->driver->ops->tiocmget(tty);
338 		BT_DBG("Current tiocm 0x%x", status);
339 
340 		set &= ~(TIOCM_OUT2 | TIOCM_RTS);
341 		clear = ~set;
342 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
343 		       TIOCM_OUT2 | TIOCM_LOOP;
344 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
345 			 TIOCM_OUT2 | TIOCM_LOOP;
346 		status = tty->driver->ops->tiocmset(tty, set, clear);
347 		BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
348 	} else {
349 		/* Set RTS to allow the device to send again */
350 		status = tty->driver->ops->tiocmget(tty);
351 		BT_DBG("Current tiocm 0x%x", status);
352 
353 		set |= (TIOCM_OUT2 | TIOCM_RTS);
354 		clear = ~set;
355 		set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
356 		       TIOCM_OUT2 | TIOCM_LOOP;
357 		clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
358 			 TIOCM_OUT2 | TIOCM_LOOP;
359 		status = tty->driver->ops->tiocmset(tty, set, clear);
360 		BT_DBG("Setting RTS: %s", status ? "failed" : "success");
361 
362 		/* Re-enable hardware flow control */
363 		ktermios = tty->termios;
364 		ktermios.c_cflag |= CRTSCTS;
365 		status = tty_set_termios(tty, &ktermios);
366 		BT_DBG("Enabling hardware flow control: %s",
367 		       status ? "failed" : "success");
368 	}
369 }
370 
hci_uart_set_speeds(struct hci_uart * hu,unsigned int init_speed,unsigned int oper_speed)371 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
372 			 unsigned int oper_speed)
373 {
374 	hu->init_speed = init_speed;
375 	hu->oper_speed = oper_speed;
376 }
377 
hci_uart_set_baudrate(struct hci_uart * hu,unsigned int speed)378 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
379 {
380 	struct tty_struct *tty = hu->tty;
381 	struct ktermios ktermios;
382 
383 	ktermios = tty->termios;
384 	ktermios.c_cflag &= ~CBAUD;
385 	tty_termios_encode_baud_rate(&ktermios, speed, speed);
386 
387 	/* tty_set_termios() return not checked as it is always 0 */
388 	tty_set_termios(tty, &ktermios);
389 
390 	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
391 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
392 }
393 
hci_uart_setup(struct hci_dev * hdev)394 static int hci_uart_setup(struct hci_dev *hdev)
395 {
396 	struct hci_uart *hu = hci_get_drvdata(hdev);
397 	struct hci_rp_read_local_version *ver;
398 	struct sk_buff *skb;
399 	unsigned int speed;
400 	int err;
401 
402 	/* Init speed if any */
403 	if (hu->init_speed)
404 		speed = hu->init_speed;
405 	else if (hu->proto->init_speed)
406 		speed = hu->proto->init_speed;
407 	else
408 		speed = 0;
409 
410 	if (speed)
411 		hci_uart_set_baudrate(hu, speed);
412 
413 	/* Operational speed if any */
414 	if (hu->oper_speed)
415 		speed = hu->oper_speed;
416 	else if (hu->proto->oper_speed)
417 		speed = hu->proto->oper_speed;
418 	else
419 		speed = 0;
420 
421 	if (hu->proto->set_baudrate && speed) {
422 		err = hu->proto->set_baudrate(hu, speed);
423 		if (!err)
424 			hci_uart_set_baudrate(hu, speed);
425 	}
426 
427 	if (hu->proto->setup)
428 		return hu->proto->setup(hu);
429 
430 	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
431 		return 0;
432 
433 	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
434 			     HCI_INIT_TIMEOUT);
435 	if (IS_ERR(skb)) {
436 		BT_ERR("%s: Reading local version information failed (%ld)",
437 		       hdev->name, PTR_ERR(skb));
438 		return 0;
439 	}
440 
441 	if (skb->len != sizeof(*ver)) {
442 		BT_ERR("%s: Event length mismatch for version information",
443 		       hdev->name);
444 		goto done;
445 	}
446 
447 	ver = (struct hci_rp_read_local_version *)skb->data;
448 
449 	switch (le16_to_cpu(ver->manufacturer)) {
450 #ifdef CONFIG_BT_HCIUART_INTEL
451 	case 2:
452 		hdev->set_bdaddr = btintel_set_bdaddr;
453 		btintel_check_bdaddr(hdev);
454 		break;
455 #endif
456 #ifdef CONFIG_BT_HCIUART_BCM
457 	case 15:
458 		hdev->set_bdaddr = btbcm_set_bdaddr;
459 		btbcm_check_bdaddr(hdev);
460 		break;
461 #endif
462 	default:
463 		break;
464 	}
465 
466 done:
467 	kfree_skb(skb);
468 	return 0;
469 }
470 
471 /* ------ LDISC part ------ */
472 /* hci_uart_tty_open
473  *
474  *     Called when line discipline changed to HCI_UART.
475  *
476  * Arguments:
477  *     tty    pointer to tty info structure
478  * Return Value:
479  *     0 if success, otherwise error code
480  */
hci_uart_tty_open(struct tty_struct * tty)481 static int hci_uart_tty_open(struct tty_struct *tty)
482 {
483 	struct hci_uart *hu;
484 
485 	BT_DBG("tty %p", tty);
486 
487 	/* Error if the tty has no write op instead of leaving an exploitable
488 	 * hole
489 	 */
490 	if (tty->ops->write == NULL)
491 		return -EOPNOTSUPP;
492 
493 	hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
494 	if (!hu) {
495 		BT_ERR("Can't allocate control structure");
496 		return -ENFILE;
497 	}
498 	if (percpu_init_rwsem(&hu->proto_lock)) {
499 		BT_ERR("Can't allocate semaphore structure");
500 		kfree(hu);
501 		return -ENOMEM;
502 	}
503 
504 	tty->disc_data = hu;
505 	hu->tty = tty;
506 	tty->receive_room = 65536;
507 
508 	/* disable alignment support by default */
509 	hu->alignment = 1;
510 	hu->padding = 0;
511 
512 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
513 	INIT_WORK(&hu->write_work, hci_uart_write_work);
514 
515 	/* Flush any pending characters in the driver */
516 	tty_driver_flush_buffer(tty);
517 
518 	return 0;
519 }
520 
521 /* hci_uart_tty_close()
522  *
523  *    Called when the line discipline is changed to something
524  *    else, the tty is closed, or the tty detects a hangup.
525  */
hci_uart_tty_close(struct tty_struct * tty)526 static void hci_uart_tty_close(struct tty_struct *tty)
527 {
528 	struct hci_uart *hu = tty->disc_data;
529 	struct hci_dev *hdev;
530 
531 	BT_DBG("tty %p", tty);
532 
533 	/* Detach from the tty */
534 	tty->disc_data = NULL;
535 
536 	if (!hu)
537 		return;
538 
539 	hdev = hu->hdev;
540 	if (hdev)
541 		hci_uart_close(hdev);
542 
543 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
544 		percpu_down_write(&hu->proto_lock);
545 		clear_bit(HCI_UART_PROTO_READY, &hu->flags);
546 		percpu_up_write(&hu->proto_lock);
547 
548 		cancel_work_sync(&hu->init_ready);
549 		cancel_work_sync(&hu->write_work);
550 
551 		if (hdev) {
552 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
553 				hci_unregister_dev(hdev);
554 			hci_free_dev(hdev);
555 		}
556 		hu->proto->close(hu);
557 	}
558 	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
559 
560 	percpu_free_rwsem(&hu->proto_lock);
561 
562 	kfree(hu);
563 }
564 
565 /* hci_uart_tty_wakeup()
566  *
567  *    Callback for transmit wakeup. Called when low level
568  *    device driver can accept more send data.
569  *
570  * Arguments:        tty    pointer to associated tty instance data
571  * Return Value:    None
572  */
hci_uart_tty_wakeup(struct tty_struct * tty)573 static void hci_uart_tty_wakeup(struct tty_struct *tty)
574 {
575 	struct hci_uart *hu = tty->disc_data;
576 
577 	BT_DBG("");
578 
579 	if (!hu)
580 		return;
581 
582 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
583 
584 	if (tty != hu->tty)
585 		return;
586 
587 	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
588 		hci_uart_tx_wakeup(hu);
589 }
590 
591 /* hci_uart_tty_receive()
592  *
593  *     Called by tty low level driver when receive data is
594  *     available.
595  *
596  * Arguments:  tty          pointer to tty isntance data
597  *             data         pointer to received data
598  *             flags        pointer to flags for data
599  *             count        count of received data in bytes
600  *
601  * Return Value:    None
602  */
hci_uart_tty_receive(struct tty_struct * tty,const u8 * data,char * flags,int count)603 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
604 				 char *flags, int count)
605 {
606 	struct hci_uart *hu = tty->disc_data;
607 
608 	if (!hu || tty != hu->tty)
609 		return;
610 
611 	percpu_down_read(&hu->proto_lock);
612 
613 	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
614 		percpu_up_read(&hu->proto_lock);
615 		return;
616 	}
617 
618 	/* It does not need a lock here as it is already protected by a mutex in
619 	 * tty caller
620 	 */
621 	hu->proto->recv(hu, data, count);
622 	percpu_up_read(&hu->proto_lock);
623 
624 	if (hu->hdev)
625 		hu->hdev->stat.byte_rx += count;
626 
627 	tty_unthrottle(tty);
628 }
629 
hci_uart_register_dev(struct hci_uart * hu)630 static int hci_uart_register_dev(struct hci_uart *hu)
631 {
632 	struct hci_dev *hdev;
633 	int err;
634 
635 	BT_DBG("");
636 
637 	/* Initialize and register HCI device */
638 	hdev = hci_alloc_dev();
639 	if (!hdev) {
640 		BT_ERR("Can't allocate HCI device");
641 		return -ENOMEM;
642 	}
643 
644 	hu->hdev = hdev;
645 
646 	hdev->bus = HCI_UART;
647 	hci_set_drvdata(hdev, hu);
648 
649 	/* Only when vendor specific setup callback is provided, consider
650 	 * the manufacturer information valid. This avoids filling in the
651 	 * value for Ericsson when nothing is specified.
652 	 */
653 	if (hu->proto->setup)
654 		hdev->manufacturer = hu->proto->manufacturer;
655 
656 	hdev->open  = hci_uart_open;
657 	hdev->close = hci_uart_close;
658 	hdev->flush = hci_uart_flush;
659 	hdev->send  = hci_uart_send_frame;
660 	hdev->setup = hci_uart_setup;
661 	SET_HCIDEV_DEV(hdev, hu->tty->dev);
662 
663 	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
664 		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
665 
666 	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
667 		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
668 
669 	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
670 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
671 
672 	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
673 		hdev->dev_type = HCI_AMP;
674 	else
675 		hdev->dev_type = HCI_PRIMARY;
676 
677 	/* Only call open() for the protocol after hdev is fully initialized as
678 	 * open() (or a timer/workqueue it starts) may attempt to reference it.
679 	 */
680 	err = hu->proto->open(hu);
681 	if (err) {
682 		hu->hdev = NULL;
683 		hci_free_dev(hdev);
684 		return err;
685 	}
686 
687 	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
688 		return 0;
689 
690 	if (hci_register_dev(hdev) < 0) {
691 		BT_ERR("Can't register HCI device");
692 		hu->proto->close(hu);
693 		hu->hdev = NULL;
694 		hci_free_dev(hdev);
695 		return -ENODEV;
696 	}
697 
698 	set_bit(HCI_UART_REGISTERED, &hu->flags);
699 
700 	return 0;
701 }
702 
hci_uart_set_proto(struct hci_uart * hu,int id)703 static int hci_uart_set_proto(struct hci_uart *hu, int id)
704 {
705 	const struct hci_uart_proto *p;
706 	int err;
707 
708 	p = hci_uart_get_proto(id);
709 	if (!p)
710 		return -EPROTONOSUPPORT;
711 
712 	hu->proto = p;
713 
714 	err = hci_uart_register_dev(hu);
715 	if (err) {
716 		return err;
717 	}
718 
719 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
720 	return 0;
721 }
722 
hci_uart_set_flags(struct hci_uart * hu,unsigned long flags)723 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
724 {
725 	unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
726 				    BIT(HCI_UART_RESET_ON_INIT) |
727 				    BIT(HCI_UART_CREATE_AMP) |
728 				    BIT(HCI_UART_INIT_PENDING) |
729 				    BIT(HCI_UART_EXT_CONFIG) |
730 				    BIT(HCI_UART_VND_DETECT);
731 
732 	if (flags & ~valid_flags)
733 		return -EINVAL;
734 
735 	hu->hdev_flags = flags;
736 
737 	return 0;
738 }
739 
740 /* hci_uart_tty_ioctl()
741  *
742  *    Process IOCTL system call for the tty device.
743  *
744  * Arguments:
745  *
746  *    tty        pointer to tty instance data
747  *    file       pointer to open file object for device
748  *    cmd        IOCTL command code
749  *    arg        argument for IOCTL call (cmd dependent)
750  *
751  * Return Value:    Command dependent
752  */
hci_uart_tty_ioctl(struct tty_struct * tty,struct file * file,unsigned int cmd,unsigned long arg)753 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
754 			      unsigned int cmd, unsigned long arg)
755 {
756 	struct hci_uart *hu = tty->disc_data;
757 	int err = 0;
758 
759 	BT_DBG("");
760 
761 	/* Verify the status of the device */
762 	if (!hu)
763 		return -EBADF;
764 
765 	switch (cmd) {
766 	case HCIUARTSETPROTO:
767 		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
768 			err = hci_uart_set_proto(hu, arg);
769 			if (err)
770 				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
771 		} else
772 			err = -EBUSY;
773 		break;
774 
775 	case HCIUARTGETPROTO:
776 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
777 			err = hu->proto->id;
778 		else
779 			err = -EUNATCH;
780 		break;
781 
782 	case HCIUARTGETDEVICE:
783 		if (test_bit(HCI_UART_REGISTERED, &hu->flags))
784 			err = hu->hdev->id;
785 		else
786 			err = -EUNATCH;
787 		break;
788 
789 	case HCIUARTSETFLAGS:
790 		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
791 			err = -EBUSY;
792 		else
793 			err = hci_uart_set_flags(hu, arg);
794 		break;
795 
796 	case HCIUARTGETFLAGS:
797 		err = hu->hdev_flags;
798 		break;
799 
800 	default:
801 		err = n_tty_ioctl_helper(tty, file, cmd, arg);
802 		break;
803 	}
804 
805 	return err;
806 }
807 
808 /*
809  * We don't provide read/write/poll interface for user space.
810  */
hci_uart_tty_read(struct tty_struct * tty,struct file * file,unsigned char * buf,size_t nr,void ** cookie,unsigned long offset)811 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
812 				 unsigned char *buf, size_t nr,
813 				 void **cookie, unsigned long offset)
814 {
815 	return 0;
816 }
817 
hci_uart_tty_write(struct tty_struct * tty,struct file * file,const unsigned char * data,size_t count)818 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
819 				  const unsigned char *data, size_t count)
820 {
821 	return 0;
822 }
823 
hci_uart_tty_poll(struct tty_struct * tty,struct file * filp,poll_table * wait)824 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
825 				      struct file *filp, poll_table *wait)
826 {
827 	return 0;
828 }
829 
830 static struct tty_ldisc_ops hci_uart_ldisc = {
831 	.owner		= THIS_MODULE,
832 	.magic		= TTY_LDISC_MAGIC,
833 	.name		= "n_hci",
834 	.open		= hci_uart_tty_open,
835 	.close		= hci_uart_tty_close,
836 	.read		= hci_uart_tty_read,
837 	.write		= hci_uart_tty_write,
838 	.ioctl		= hci_uart_tty_ioctl,
839 	.compat_ioctl	= hci_uart_tty_ioctl,
840 	.poll		= hci_uart_tty_poll,
841 	.receive_buf	= hci_uart_tty_receive,
842 	.write_wakeup	= hci_uart_tty_wakeup,
843 };
844 
hci_uart_init(void)845 static int __init hci_uart_init(void)
846 {
847 	int err;
848 
849 	BT_INFO("HCI UART driver ver %s", VERSION);
850 
851 	/* Register the tty discipline */
852 	err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
853 	if (err) {
854 		BT_ERR("HCI line discipline registration failed. (%d)", err);
855 		return err;
856 	}
857 
858 #ifdef CONFIG_BT_HCIUART_H4
859 	h4_init();
860 #endif
861 #ifdef CONFIG_BT_HCIUART_BCSP
862 	bcsp_init();
863 #endif
864 #ifdef CONFIG_BT_HCIUART_LL
865 	ll_init();
866 #endif
867 #ifdef CONFIG_BT_HCIUART_ATH3K
868 	ath_init();
869 #endif
870 #ifdef CONFIG_BT_HCIUART_3WIRE
871 	h5_init();
872 #endif
873 #ifdef CONFIG_BT_HCIUART_INTEL
874 	intel_init();
875 #endif
876 #ifdef CONFIG_BT_HCIUART_BCM
877 	bcm_init();
878 #endif
879 #ifdef CONFIG_BT_HCIUART_QCA
880 	qca_init();
881 #endif
882 #ifdef CONFIG_BT_HCIUART_AG6XX
883 	ag6xx_init();
884 #endif
885 #ifdef CONFIG_BT_HCIUART_MRVL
886 	mrvl_init();
887 #endif
888 
889 	return 0;
890 }
891 
hci_uart_exit(void)892 static void __exit hci_uart_exit(void)
893 {
894 	int err;
895 
896 #ifdef CONFIG_BT_HCIUART_H4
897 	h4_deinit();
898 #endif
899 #ifdef CONFIG_BT_HCIUART_BCSP
900 	bcsp_deinit();
901 #endif
902 #ifdef CONFIG_BT_HCIUART_LL
903 	ll_deinit();
904 #endif
905 #ifdef CONFIG_BT_HCIUART_ATH3K
906 	ath_deinit();
907 #endif
908 #ifdef CONFIG_BT_HCIUART_3WIRE
909 	h5_deinit();
910 #endif
911 #ifdef CONFIG_BT_HCIUART_INTEL
912 	intel_deinit();
913 #endif
914 #ifdef CONFIG_BT_HCIUART_BCM
915 	bcm_deinit();
916 #endif
917 #ifdef CONFIG_BT_HCIUART_QCA
918 	qca_deinit();
919 #endif
920 #ifdef CONFIG_BT_HCIUART_AG6XX
921 	ag6xx_deinit();
922 #endif
923 #ifdef CONFIG_BT_HCIUART_MRVL
924 	mrvl_deinit();
925 #endif
926 
927 	/* Release tty registration of line discipline */
928 	err = tty_unregister_ldisc(N_HCI);
929 	if (err)
930 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
931 }
932 
933 module_init(hci_uart_init);
934 module_exit(hci_uart_exit);
935 
936 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
937 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
938 MODULE_VERSION(VERSION);
939 MODULE_LICENSE("GPL");
940 MODULE_ALIAS_LDISC(N_HCI);
941