3 * Bluetooth HCI UART driver
5 * Copyright (C) 2000-2001 Qualcomm Incorporated
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.
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.
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
26 #include <linux/module.h>
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>
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>
46 #include <net/bluetooth/bluetooth.h>
47 #include <net/bluetooth/hci_core.h>
55 static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
57 int hci_uart_register_proto(const struct hci_uart_proto *p)
59 if (p->id >= HCI_UART_MAX_PROTO)
67 BT_INFO("HCI UART protocol %s registered", p->name);
72 int hci_uart_unregister_proto(const struct hci_uart_proto *p)
74 if (p->id >= HCI_UART_MAX_PROTO)
85 static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
87 if (id >= HCI_UART_MAX_PROTO)
93 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
95 struct hci_dev *hdev = hu->hdev;
97 /* Update HCI stat counters */
103 case HCI_ACLDATA_PKT:
107 case HCI_SCODATA_PKT:
113 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
115 struct sk_buff *skb = hu->tx_skb;
118 percpu_down_read(&hu->proto_lock);
120 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
121 skb = hu->proto->dequeue(hu);
123 percpu_up_read(&hu->proto_lock);
131 int hci_uart_tx_wakeup(struct hci_uart *hu)
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.
139 if (!percpu_down_read_trylock(&hu->proto_lock))
142 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
145 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
146 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
152 schedule_work(&hu->write_work);
155 percpu_up_read(&hu->proto_lock);
159 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
161 static void hci_uart_write_work(struct work_struct *work)
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;
168 /* REVISIT: should we cope with bad skbs or ->write() returning
173 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
175 while ((skb = hci_uart_dequeue(hu))) {
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;
188 hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
192 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
195 clear_bit(HCI_UART_SENDING, &hu->tx_state);
198 void hci_uart_init_work(struct work_struct *work)
200 struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
202 struct hci_dev *hdev;
204 if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
207 err = hci_register_dev(hu->hdev);
209 BT_ERR("Can't register HCI device");
213 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
214 hu->proto->close(hu);
218 set_bit(HCI_UART_REGISTERED, &hu->flags);
221 int hci_uart_init_ready(struct hci_uart *hu)
223 if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
226 schedule_work(&hu->init_ready);
231 /* ------- Interface to HCI layer ------ */
233 static int hci_uart_flush(struct hci_dev *hdev)
235 struct hci_uart *hu = hci_get_drvdata(hdev);
236 struct tty_struct *tty = hu->tty;
238 BT_DBG("hdev %p tty %p", hdev, tty);
241 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
244 /* Flush any pending characters in the driver and discipline. */
245 tty_ldisc_flush(tty);
246 tty_driver_flush_buffer(tty);
248 percpu_down_read(&hu->proto_lock);
250 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
251 hu->proto->flush(hu);
253 percpu_up_read(&hu->proto_lock);
258 /* Initialize device */
259 static int hci_uart_open(struct hci_dev *hdev)
261 BT_DBG("%s %p", hdev->name, hdev);
263 /* Undo clearing this from hci_uart_close() */
264 hdev->flush = hci_uart_flush;
270 static int hci_uart_close(struct hci_dev *hdev)
272 BT_DBG("hdev %p", hdev);
274 hci_uart_flush(hdev);
279 /* Send frames from HCI layer */
280 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
282 struct hci_uart *hu = hci_get_drvdata(hdev);
284 BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
287 percpu_down_read(&hu->proto_lock);
289 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
290 percpu_up_read(&hu->proto_lock);
294 hu->proto->enqueue(hu, skb);
295 percpu_up_read(&hu->proto_lock);
297 hci_uart_tx_wakeup(hu);
302 /* Flow control or un-flow control the device */
303 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
305 struct tty_struct *tty = hu->tty;
306 struct ktermios ktermios;
308 unsigned int set = 0;
309 unsigned int clear = 0;
312 serdev_device_set_flow_control(hu->serdev, !enable);
313 serdev_device_set_rts(hu->serdev, !enable);
318 /* Disable hardware flow control */
319 ktermios = tty->termios;
320 ktermios.c_cflag &= ~CRTSCTS;
321 status = tty_set_termios(tty, &ktermios);
322 BT_DBG("Disabling hardware flow control: %s",
323 status ? "failed" : "success");
325 /* Clear RTS to prevent the device from sending */
326 /* Most UARTs need OUT2 to enable interrupts */
327 status = tty->driver->ops->tiocmget(tty);
328 BT_DBG("Current tiocm 0x%x", status);
330 set &= ~(TIOCM_OUT2 | TIOCM_RTS);
332 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
333 TIOCM_OUT2 | TIOCM_LOOP;
334 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
335 TIOCM_OUT2 | TIOCM_LOOP;
336 status = tty->driver->ops->tiocmset(tty, set, clear);
337 BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
339 /* Set RTS to allow the device to send again */
340 status = tty->driver->ops->tiocmget(tty);
341 BT_DBG("Current tiocm 0x%x", status);
343 set |= (TIOCM_OUT2 | TIOCM_RTS);
345 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
346 TIOCM_OUT2 | TIOCM_LOOP;
347 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
348 TIOCM_OUT2 | TIOCM_LOOP;
349 status = tty->driver->ops->tiocmset(tty, set, clear);
350 BT_DBG("Setting RTS: %s", status ? "failed" : "success");
352 /* Re-enable hardware flow control */
353 ktermios = tty->termios;
354 ktermios.c_cflag |= CRTSCTS;
355 status = tty_set_termios(tty, &ktermios);
356 BT_DBG("Enabling hardware flow control: %s",
357 status ? "failed" : "success");
361 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
362 unsigned int oper_speed)
364 hu->init_speed = init_speed;
365 hu->oper_speed = oper_speed;
368 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
370 struct tty_struct *tty = hu->tty;
371 struct ktermios ktermios;
373 ktermios = tty->termios;
374 ktermios.c_cflag &= ~CBAUD;
375 tty_termios_encode_baud_rate(&ktermios, speed, speed);
377 /* tty_set_termios() return not checked as it is always 0 */
378 tty_set_termios(tty, &ktermios);
380 BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
381 tty->termios.c_ispeed, tty->termios.c_ospeed);
384 static int hci_uart_setup(struct hci_dev *hdev)
386 struct hci_uart *hu = hci_get_drvdata(hdev);
387 struct hci_rp_read_local_version *ver;
392 /* Init speed if any */
394 speed = hu->init_speed;
395 else if (hu->proto->init_speed)
396 speed = hu->proto->init_speed;
401 hci_uart_set_baudrate(hu, speed);
403 /* Operational speed if any */
405 speed = hu->oper_speed;
406 else if (hu->proto->oper_speed)
407 speed = hu->proto->oper_speed;
411 if (hu->proto->set_baudrate && speed) {
412 err = hu->proto->set_baudrate(hu, speed);
414 hci_uart_set_baudrate(hu, speed);
417 if (hu->proto->setup)
418 return hu->proto->setup(hu);
420 if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
423 skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
426 BT_ERR("%s: Reading local version information failed (%ld)",
427 hdev->name, PTR_ERR(skb));
431 if (skb->len != sizeof(*ver)) {
432 BT_ERR("%s: Event length mismatch for version information",
437 ver = (struct hci_rp_read_local_version *)skb->data;
439 switch (le16_to_cpu(ver->manufacturer)) {
440 #ifdef CONFIG_BT_HCIUART_INTEL
442 hdev->set_bdaddr = btintel_set_bdaddr;
443 btintel_check_bdaddr(hdev);
446 #ifdef CONFIG_BT_HCIUART_BCM
448 hdev->set_bdaddr = btbcm_set_bdaddr;
449 btbcm_check_bdaddr(hdev);
461 /* ------ LDISC part ------ */
464 * Called when line discipline changed to HCI_UART.
467 * tty pointer to tty info structure
469 * 0 if success, otherwise error code
471 static int hci_uart_tty_open(struct tty_struct *tty)
475 BT_DBG("tty %p", tty);
477 /* Error if the tty has no write op instead of leaving an exploitable
480 if (tty->ops->write == NULL)
483 hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
485 BT_ERR("Can't allocate control structure");
491 tty->receive_room = 65536;
493 /* disable alignment support by default */
497 INIT_WORK(&hu->init_ready, hci_uart_init_work);
498 INIT_WORK(&hu->write_work, hci_uart_write_work);
500 percpu_init_rwsem(&hu->proto_lock);
502 /* Flush any pending characters in the driver */
503 tty_driver_flush_buffer(tty);
508 /* hci_uart_tty_close()
510 * Called when the line discipline is changed to something
511 * else, the tty is closed, or the tty detects a hangup.
513 static void hci_uart_tty_close(struct tty_struct *tty)
515 struct hci_uart *hu = tty->disc_data;
516 struct hci_dev *hdev;
518 BT_DBG("tty %p", tty);
520 /* Detach from the tty */
521 tty->disc_data = NULL;
528 hci_uart_close(hdev);
530 if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
531 percpu_down_write(&hu->proto_lock);
532 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
533 percpu_up_write(&hu->proto_lock);
535 cancel_work_sync(&hu->write_work);
538 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
539 hci_unregister_dev(hdev);
542 hu->proto->close(hu);
544 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
549 /* hci_uart_tty_wakeup()
551 * Callback for transmit wakeup. Called when low level
552 * device driver can accept more send data.
554 * Arguments: tty pointer to associated tty instance data
557 static void hci_uart_tty_wakeup(struct tty_struct *tty)
559 struct hci_uart *hu = tty->disc_data;
566 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
571 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
572 hci_uart_tx_wakeup(hu);
575 /* hci_uart_tty_receive()
577 * Called by tty low level driver when receive data is
580 * Arguments: tty pointer to tty isntance data
581 * data pointer to received data
582 * flags pointer to flags for data
583 * count count of received data in bytes
587 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
588 char *flags, int count)
590 struct hci_uart *hu = tty->disc_data;
592 if (!hu || tty != hu->tty)
595 percpu_down_read(&hu->proto_lock);
597 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
598 percpu_up_read(&hu->proto_lock);
602 /* It does not need a lock here as it is already protected by a mutex in
605 hu->proto->recv(hu, data, count);
606 percpu_up_read(&hu->proto_lock);
609 hu->hdev->stat.byte_rx += count;
614 static int hci_uart_register_dev(struct hci_uart *hu)
616 struct hci_dev *hdev;
620 /* Initialize and register HCI device */
621 hdev = hci_alloc_dev();
623 BT_ERR("Can't allocate HCI device");
629 hdev->bus = HCI_UART;
630 hci_set_drvdata(hdev, hu);
632 /* Only when vendor specific setup callback is provided, consider
633 * the manufacturer information valid. This avoids filling in the
634 * value for Ericsson when nothing is specified.
636 if (hu->proto->setup)
637 hdev->manufacturer = hu->proto->manufacturer;
639 hdev->open = hci_uart_open;
640 hdev->close = hci_uart_close;
641 hdev->flush = hci_uart_flush;
642 hdev->send = hci_uart_send_frame;
643 hdev->setup = hci_uart_setup;
644 SET_HCIDEV_DEV(hdev, hu->tty->dev);
646 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
647 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
649 if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
650 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
652 if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
653 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
655 if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
656 hdev->dev_type = HCI_AMP;
658 hdev->dev_type = HCI_PRIMARY;
660 if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
663 if (hci_register_dev(hdev) < 0) {
664 BT_ERR("Can't register HCI device");
670 set_bit(HCI_UART_REGISTERED, &hu->flags);
675 static int hci_uart_set_proto(struct hci_uart *hu, int id)
677 const struct hci_uart_proto *p;
680 p = hci_uart_get_proto(id);
682 return -EPROTONOSUPPORT;
689 set_bit(HCI_UART_PROTO_READY, &hu->flags);
691 err = hci_uart_register_dev(hu);
693 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
701 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
703 unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
704 BIT(HCI_UART_RESET_ON_INIT) |
705 BIT(HCI_UART_CREATE_AMP) |
706 BIT(HCI_UART_INIT_PENDING) |
707 BIT(HCI_UART_EXT_CONFIG) |
708 BIT(HCI_UART_VND_DETECT);
710 if (flags & ~valid_flags)
713 hu->hdev_flags = flags;
718 /* hci_uart_tty_ioctl()
720 * Process IOCTL system call for the tty device.
724 * tty pointer to tty instance data
725 * file pointer to open file object for device
726 * cmd IOCTL command code
727 * arg argument for IOCTL call (cmd dependent)
729 * Return Value: Command dependent
731 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
732 unsigned int cmd, unsigned long arg)
734 struct hci_uart *hu = tty->disc_data;
739 /* Verify the status of the device */
744 case HCIUARTSETPROTO:
745 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
746 err = hci_uart_set_proto(hu, arg);
748 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
753 case HCIUARTGETPROTO:
754 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
760 case HCIUARTGETDEVICE:
761 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
767 case HCIUARTSETFLAGS:
768 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
771 err = hci_uart_set_flags(hu, arg);
774 case HCIUARTGETFLAGS:
775 err = hu->hdev_flags;
779 err = n_tty_ioctl_helper(tty, file, cmd, arg);
787 * We don't provide read/write/poll interface for user space.
789 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
790 unsigned char __user *buf, size_t nr)
795 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
796 const unsigned char *data, size_t count)
801 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
802 struct file *filp, poll_table *wait)
807 static int __init hci_uart_init(void)
809 static struct tty_ldisc_ops hci_uart_ldisc;
812 BT_INFO("HCI UART driver ver %s", VERSION);
814 /* Register the tty discipline */
816 memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
817 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
818 hci_uart_ldisc.name = "n_hci";
819 hci_uart_ldisc.open = hci_uart_tty_open;
820 hci_uart_ldisc.close = hci_uart_tty_close;
821 hci_uart_ldisc.read = hci_uart_tty_read;
822 hci_uart_ldisc.write = hci_uart_tty_write;
823 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
824 hci_uart_ldisc.poll = hci_uart_tty_poll;
825 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
826 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
827 hci_uart_ldisc.owner = THIS_MODULE;
829 err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
831 BT_ERR("HCI line discipline registration failed. (%d)", err);
835 #ifdef CONFIG_BT_HCIUART_H4
838 #ifdef CONFIG_BT_HCIUART_BCSP
841 #ifdef CONFIG_BT_HCIUART_LL
844 #ifdef CONFIG_BT_HCIUART_ATH3K
847 #ifdef CONFIG_BT_HCIUART_3WIRE
850 #ifdef CONFIG_BT_HCIUART_INTEL
853 #ifdef CONFIG_BT_HCIUART_BCM
856 #ifdef CONFIG_BT_HCIUART_QCA
859 #ifdef CONFIG_BT_HCIUART_AG6XX
862 #ifdef CONFIG_BT_HCIUART_MRVL
869 static void __exit hci_uart_exit(void)
873 #ifdef CONFIG_BT_HCIUART_H4
876 #ifdef CONFIG_BT_HCIUART_BCSP
879 #ifdef CONFIG_BT_HCIUART_LL
882 #ifdef CONFIG_BT_HCIUART_ATH3K
885 #ifdef CONFIG_BT_HCIUART_3WIRE
888 #ifdef CONFIG_BT_HCIUART_INTEL
891 #ifdef CONFIG_BT_HCIUART_BCM
894 #ifdef CONFIG_BT_HCIUART_QCA
897 #ifdef CONFIG_BT_HCIUART_AG6XX
900 #ifdef CONFIG_BT_HCIUART_MRVL
904 /* Release tty registration of line discipline */
905 err = tty_unregister_ldisc(N_HCI);
907 BT_ERR("Can't unregister HCI line discipline (%d)", err);
910 module_init(hci_uart_init);
911 module_exit(hci_uart_exit);
914 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
915 MODULE_VERSION(VERSION);
916 MODULE_LICENSE("GPL");
917 MODULE_ALIAS_LDISC(N_HCI);