3 * Bluetooth HCI UART driver
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>
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 static 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");
210 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
211 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 ------ */
232 /* Initialize device */
233 static int hci_uart_open(struct hci_dev *hdev)
235 BT_DBG("%s %p", hdev->name, hdev);
237 /* Nothing to do for UART driver */
242 static int hci_uart_flush(struct hci_dev *hdev)
244 struct hci_uart *hu = hci_get_drvdata(hdev);
245 struct tty_struct *tty = hu->tty;
247 BT_DBG("hdev %p tty %p", hdev, tty);
250 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
253 /* Flush any pending characters in the driver and discipline. */
254 tty_ldisc_flush(tty);
255 tty_driver_flush_buffer(tty);
257 percpu_down_read(&hu->proto_lock);
259 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
260 hu->proto->flush(hu);
262 percpu_up_read(&hu->proto_lock);
268 static int hci_uart_close(struct hci_dev *hdev)
270 BT_DBG("hdev %p", hdev);
272 hci_uart_flush(hdev);
277 /* Send frames from HCI layer */
278 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
280 struct hci_uart *hu = hci_get_drvdata(hdev);
282 BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
285 percpu_down_read(&hu->proto_lock);
287 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
288 percpu_up_read(&hu->proto_lock);
292 hu->proto->enqueue(hu, skb);
293 percpu_up_read(&hu->proto_lock);
295 hci_uart_tx_wakeup(hu);
300 /* Check the underlying device or tty has flow control support */
301 bool hci_uart_has_flow_control(struct hci_uart *hu)
303 /* serdev nodes check if the needed operations are present */
307 if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
313 /* Flow control or un-flow control the device */
314 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
316 struct tty_struct *tty = hu->tty;
317 struct ktermios ktermios;
319 unsigned int set = 0;
320 unsigned int clear = 0;
323 serdev_device_set_flow_control(hu->serdev, !enable);
324 serdev_device_set_rts(hu->serdev, !enable);
329 /* Disable hardware flow control */
330 ktermios = tty->termios;
331 ktermios.c_cflag &= ~CRTSCTS;
332 status = tty_set_termios(tty, &ktermios);
333 BT_DBG("Disabling hardware flow control: %s",
334 status ? "failed" : "success");
336 /* Clear RTS to prevent the device from sending */
337 /* Most UARTs need OUT2 to enable interrupts */
338 status = tty->driver->ops->tiocmget(tty);
339 BT_DBG("Current tiocm 0x%x", status);
341 set &= ~(TIOCM_OUT2 | TIOCM_RTS);
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("Clearing RTS: %s", status ? "failed" : "success");
350 /* Set RTS to allow the device to send again */
351 status = tty->driver->ops->tiocmget(tty);
352 BT_DBG("Current tiocm 0x%x", status);
354 set |= (TIOCM_OUT2 | TIOCM_RTS);
356 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
357 TIOCM_OUT2 | TIOCM_LOOP;
358 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
359 TIOCM_OUT2 | TIOCM_LOOP;
360 status = tty->driver->ops->tiocmset(tty, set, clear);
361 BT_DBG("Setting RTS: %s", status ? "failed" : "success");
363 /* Re-enable hardware flow control */
364 ktermios = tty->termios;
365 ktermios.c_cflag |= CRTSCTS;
366 status = tty_set_termios(tty, &ktermios);
367 BT_DBG("Enabling hardware flow control: %s",
368 status ? "failed" : "success");
372 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
373 unsigned int oper_speed)
375 hu->init_speed = init_speed;
376 hu->oper_speed = oper_speed;
379 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
381 struct tty_struct *tty = hu->tty;
382 struct ktermios ktermios;
384 ktermios = tty->termios;
385 ktermios.c_cflag &= ~CBAUD;
386 tty_termios_encode_baud_rate(&ktermios, speed, speed);
388 /* tty_set_termios() return not checked as it is always 0 */
389 tty_set_termios(tty, &ktermios);
391 BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
392 tty->termios.c_ispeed, tty->termios.c_ospeed);
395 static int hci_uart_setup(struct hci_dev *hdev)
397 struct hci_uart *hu = hci_get_drvdata(hdev);
398 struct hci_rp_read_local_version *ver;
403 /* Init speed if any */
405 speed = hu->init_speed;
406 else if (hu->proto->init_speed)
407 speed = hu->proto->init_speed;
412 hci_uart_set_baudrate(hu, speed);
414 /* Operational speed if any */
416 speed = hu->oper_speed;
417 else if (hu->proto->oper_speed)
418 speed = hu->proto->oper_speed;
422 if (hu->proto->set_baudrate && speed) {
423 err = hu->proto->set_baudrate(hu, speed);
425 hci_uart_set_baudrate(hu, speed);
428 if (hu->proto->setup)
429 return hu->proto->setup(hu);
431 if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
434 skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
437 BT_ERR("%s: Reading local version information failed (%ld)",
438 hdev->name, PTR_ERR(skb));
442 if (skb->len != sizeof(*ver)) {
443 BT_ERR("%s: Event length mismatch for version information",
448 ver = (struct hci_rp_read_local_version *)skb->data;
450 switch (le16_to_cpu(ver->manufacturer)) {
451 #ifdef CONFIG_BT_HCIUART_INTEL
453 hdev->set_bdaddr = btintel_set_bdaddr;
454 btintel_check_bdaddr(hdev);
457 #ifdef CONFIG_BT_HCIUART_BCM
459 hdev->set_bdaddr = btbcm_set_bdaddr;
460 btbcm_check_bdaddr(hdev);
470 /* ------ LDISC part ------ */
473 * Called when line discipline changed to HCI_UART.
476 * tty pointer to tty info structure
478 * 0 if success, otherwise error code
480 static int hci_uart_tty_open(struct tty_struct *tty)
484 BT_DBG("tty %p", tty);
486 /* Error if the tty has no write op instead of leaving an exploitable
489 if (tty->ops->write == NULL)
492 hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
494 BT_ERR("Can't allocate control structure");
500 tty->receive_room = 65536;
502 /* disable alignment support by default */
506 INIT_WORK(&hu->init_ready, hci_uart_init_work);
507 INIT_WORK(&hu->write_work, hci_uart_write_work);
509 percpu_init_rwsem(&hu->proto_lock);
511 /* Flush any pending characters in the driver */
512 tty_driver_flush_buffer(tty);
517 /* hci_uart_tty_close()
519 * Called when the line discipline is changed to something
520 * else, the tty is closed, or the tty detects a hangup.
522 static void hci_uart_tty_close(struct tty_struct *tty)
524 struct hci_uart *hu = tty->disc_data;
525 struct hci_dev *hdev;
527 BT_DBG("tty %p", tty);
529 /* Detach from the tty */
530 tty->disc_data = NULL;
537 hci_uart_close(hdev);
539 if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
540 percpu_down_write(&hu->proto_lock);
541 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
542 percpu_up_write(&hu->proto_lock);
544 cancel_work_sync(&hu->init_ready);
545 cancel_work_sync(&hu->write_work);
548 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
549 hci_unregister_dev(hdev);
552 hu->proto->close(hu);
554 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
556 percpu_free_rwsem(&hu->proto_lock);
561 /* hci_uart_tty_wakeup()
563 * Callback for transmit wakeup. Called when low level
564 * device driver can accept more send data.
566 * Arguments: tty pointer to associated tty instance data
569 static void hci_uart_tty_wakeup(struct tty_struct *tty)
571 struct hci_uart *hu = tty->disc_data;
578 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
583 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
584 hci_uart_tx_wakeup(hu);
587 /* hci_uart_tty_receive()
589 * Called by tty low level driver when receive data is
592 * Arguments: tty pointer to tty isntance data
593 * data pointer to received data
594 * flags pointer to flags for data
595 * count count of received data in bytes
599 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
600 char *flags, int count)
602 struct hci_uart *hu = tty->disc_data;
604 if (!hu || tty != hu->tty)
607 percpu_down_read(&hu->proto_lock);
609 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
610 percpu_up_read(&hu->proto_lock);
614 /* It does not need a lock here as it is already protected by a mutex in
617 hu->proto->recv(hu, data, count);
618 percpu_up_read(&hu->proto_lock);
621 hu->hdev->stat.byte_rx += count;
626 static int hci_uart_register_dev(struct hci_uart *hu)
628 struct hci_dev *hdev;
633 /* Initialize and register HCI device */
634 hdev = hci_alloc_dev();
636 BT_ERR("Can't allocate HCI device");
642 hdev->bus = HCI_UART;
643 hci_set_drvdata(hdev, hu);
645 /* Only when vendor specific setup callback is provided, consider
646 * the manufacturer information valid. This avoids filling in the
647 * value for Ericsson when nothing is specified.
649 if (hu->proto->setup)
650 hdev->manufacturer = hu->proto->manufacturer;
652 hdev->open = hci_uart_open;
653 hdev->close = hci_uart_close;
654 hdev->flush = hci_uart_flush;
655 hdev->send = hci_uart_send_frame;
656 hdev->setup = hci_uart_setup;
657 SET_HCIDEV_DEV(hdev, hu->tty->dev);
659 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
660 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
662 if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
663 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
665 if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
666 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
668 if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
669 hdev->dev_type = HCI_AMP;
671 hdev->dev_type = HCI_PRIMARY;
673 /* Only call open() for the protocol after hdev is fully initialized as
674 * open() (or a timer/workqueue it starts) may attempt to reference it.
676 err = hu->proto->open(hu);
683 if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
686 if (hci_register_dev(hdev) < 0) {
687 BT_ERR("Can't register HCI device");
688 hu->proto->close(hu);
694 set_bit(HCI_UART_REGISTERED, &hu->flags);
699 static int hci_uart_set_proto(struct hci_uart *hu, int id)
701 const struct hci_uart_proto *p;
704 p = hci_uart_get_proto(id);
706 return -EPROTONOSUPPORT;
710 err = hci_uart_register_dev(hu);
715 set_bit(HCI_UART_PROTO_READY, &hu->flags);
719 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
721 unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
722 BIT(HCI_UART_RESET_ON_INIT) |
723 BIT(HCI_UART_CREATE_AMP) |
724 BIT(HCI_UART_INIT_PENDING) |
725 BIT(HCI_UART_EXT_CONFIG) |
726 BIT(HCI_UART_VND_DETECT);
728 if (flags & ~valid_flags)
731 hu->hdev_flags = flags;
736 /* hci_uart_tty_ioctl()
738 * Process IOCTL system call for the tty device.
742 * tty pointer to tty instance data
743 * file pointer to open file object for device
744 * cmd IOCTL command code
745 * arg argument for IOCTL call (cmd dependent)
747 * Return Value: Command dependent
749 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
750 unsigned int cmd, unsigned long arg)
752 struct hci_uart *hu = tty->disc_data;
757 /* Verify the status of the device */
762 case HCIUARTSETPROTO:
763 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
764 err = hci_uart_set_proto(hu, arg);
766 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
771 case HCIUARTGETPROTO:
772 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
778 case HCIUARTGETDEVICE:
779 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
785 case HCIUARTSETFLAGS:
786 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
789 err = hci_uart_set_flags(hu, arg);
792 case HCIUARTGETFLAGS:
793 err = hu->hdev_flags;
797 err = n_tty_ioctl_helper(tty, file, cmd, arg);
805 * We don't provide read/write/poll interface for user space.
807 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
808 unsigned char __user *buf, size_t nr)
813 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
814 const unsigned char *data, size_t count)
819 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
820 struct file *filp, poll_table *wait)
825 static int __init hci_uart_init(void)
827 static struct tty_ldisc_ops hci_uart_ldisc;
830 BT_INFO("HCI UART driver ver %s", VERSION);
832 /* Register the tty discipline */
834 memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
835 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
836 hci_uart_ldisc.name = "n_hci";
837 hci_uart_ldisc.open = hci_uart_tty_open;
838 hci_uart_ldisc.close = hci_uart_tty_close;
839 hci_uart_ldisc.read = hci_uart_tty_read;
840 hci_uart_ldisc.write = hci_uart_tty_write;
841 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
842 hci_uart_ldisc.poll = hci_uart_tty_poll;
843 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
844 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
845 hci_uart_ldisc.owner = THIS_MODULE;
847 err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
849 BT_ERR("HCI line discipline registration failed. (%d)", err);
853 #ifdef CONFIG_BT_HCIUART_H4
856 #ifdef CONFIG_BT_HCIUART_BCSP
859 #ifdef CONFIG_BT_HCIUART_LL
862 #ifdef CONFIG_BT_HCIUART_ATH3K
865 #ifdef CONFIG_BT_HCIUART_3WIRE
868 #ifdef CONFIG_BT_HCIUART_INTEL
871 #ifdef CONFIG_BT_HCIUART_BCM
874 #ifdef CONFIG_BT_HCIUART_QCA
877 #ifdef CONFIG_BT_HCIUART_AG6XX
880 #ifdef CONFIG_BT_HCIUART_MRVL
887 static void __exit hci_uart_exit(void)
891 #ifdef CONFIG_BT_HCIUART_H4
894 #ifdef CONFIG_BT_HCIUART_BCSP
897 #ifdef CONFIG_BT_HCIUART_LL
900 #ifdef CONFIG_BT_HCIUART_ATH3K
903 #ifdef CONFIG_BT_HCIUART_3WIRE
906 #ifdef CONFIG_BT_HCIUART_INTEL
909 #ifdef CONFIG_BT_HCIUART_BCM
912 #ifdef CONFIG_BT_HCIUART_QCA
915 #ifdef CONFIG_BT_HCIUART_AG6XX
918 #ifdef CONFIG_BT_HCIUART_MRVL
922 /* Release tty registration of line discipline */
923 err = tty_unregister_ldisc(N_HCI);
925 BT_ERR("Can't unregister HCI line discipline (%d)", err);
928 module_init(hci_uart_init);
929 module_exit(hci_uart_exit);
931 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
932 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
933 MODULE_VERSION(VERSION);
934 MODULE_LICENSE("GPL");
935 MODULE_ALIAS_LDISC(N_HCI);