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 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 ------ */
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 /* Check the underlying device or tty has flow control support */
303 bool hci_uart_has_flow_control(struct hci_uart *hu)
305 /* serdev nodes check if the needed operations are present */
309 if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
315 /* Flow control or un-flow control the device */
316 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
318 struct tty_struct *tty = hu->tty;
319 struct ktermios ktermios;
321 unsigned int set = 0;
322 unsigned int clear = 0;
325 serdev_device_set_flow_control(hu->serdev, !enable);
326 serdev_device_set_rts(hu->serdev, !enable);
331 /* Disable hardware flow control */
332 ktermios = tty->termios;
333 ktermios.c_cflag &= ~CRTSCTS;
334 status = tty_set_termios(tty, &ktermios);
335 BT_DBG("Disabling hardware flow control: %s",
336 status ? "failed" : "success");
338 /* Clear RTS to prevent the device from sending */
339 /* Most UARTs need OUT2 to enable interrupts */
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("Clearing RTS: %s", status ? "failed" : "success");
352 /* Set RTS to allow the device to send again */
353 status = tty->driver->ops->tiocmget(tty);
354 BT_DBG("Current tiocm 0x%x", status);
356 set |= (TIOCM_OUT2 | TIOCM_RTS);
358 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
359 TIOCM_OUT2 | TIOCM_LOOP;
360 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
361 TIOCM_OUT2 | TIOCM_LOOP;
362 status = tty->driver->ops->tiocmset(tty, set, clear);
363 BT_DBG("Setting RTS: %s", status ? "failed" : "success");
365 /* Re-enable hardware flow control */
366 ktermios = tty->termios;
367 ktermios.c_cflag |= CRTSCTS;
368 status = tty_set_termios(tty, &ktermios);
369 BT_DBG("Enabling hardware flow control: %s",
370 status ? "failed" : "success");
374 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
375 unsigned int oper_speed)
377 hu->init_speed = init_speed;
378 hu->oper_speed = oper_speed;
381 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
383 struct tty_struct *tty = hu->tty;
384 struct ktermios ktermios;
386 ktermios = tty->termios;
387 ktermios.c_cflag &= ~CBAUD;
388 tty_termios_encode_baud_rate(&ktermios, speed, speed);
390 /* tty_set_termios() return not checked as it is always 0 */
391 tty_set_termios(tty, &ktermios);
393 BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
394 tty->termios.c_ispeed, tty->termios.c_ospeed);
397 static int hci_uart_setup(struct hci_dev *hdev)
399 struct hci_uart *hu = hci_get_drvdata(hdev);
400 struct hci_rp_read_local_version *ver;
405 /* Init speed if any */
407 speed = hu->init_speed;
408 else if (hu->proto->init_speed)
409 speed = hu->proto->init_speed;
414 hci_uart_set_baudrate(hu, speed);
416 /* Operational speed if any */
418 speed = hu->oper_speed;
419 else if (hu->proto->oper_speed)
420 speed = hu->proto->oper_speed;
424 if (hu->proto->set_baudrate && speed) {
425 err = hu->proto->set_baudrate(hu, speed);
427 hci_uart_set_baudrate(hu, speed);
430 if (hu->proto->setup)
431 return hu->proto->setup(hu);
433 if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
436 skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
439 BT_ERR("%s: Reading local version information failed (%ld)",
440 hdev->name, PTR_ERR(skb));
444 if (skb->len != sizeof(*ver)) {
445 BT_ERR("%s: Event length mismatch for version information",
450 ver = (struct hci_rp_read_local_version *)skb->data;
452 switch (le16_to_cpu(ver->manufacturer)) {
453 #ifdef CONFIG_BT_HCIUART_INTEL
455 hdev->set_bdaddr = btintel_set_bdaddr;
456 btintel_check_bdaddr(hdev);
459 #ifdef CONFIG_BT_HCIUART_BCM
461 hdev->set_bdaddr = btbcm_set_bdaddr;
462 btbcm_check_bdaddr(hdev);
474 /* ------ LDISC part ------ */
477 * Called when line discipline changed to HCI_UART.
480 * tty pointer to tty info structure
482 * 0 if success, otherwise error code
484 static int hci_uart_tty_open(struct tty_struct *tty)
488 BT_DBG("tty %p", tty);
490 /* Error if the tty has no write op instead of leaving an exploitable
493 if (tty->ops->write == NULL)
496 hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
498 BT_ERR("Can't allocate control structure");
504 tty->receive_room = 65536;
506 /* disable alignment support by default */
510 INIT_WORK(&hu->init_ready, hci_uart_init_work);
511 INIT_WORK(&hu->write_work, hci_uart_write_work);
513 percpu_init_rwsem(&hu->proto_lock);
515 /* Flush any pending characters in the driver */
516 tty_driver_flush_buffer(tty);
521 /* hci_uart_tty_close()
523 * Called when the line discipline is changed to something
524 * else, the tty is closed, or the tty detects a hangup.
526 static void hci_uart_tty_close(struct tty_struct *tty)
528 struct hci_uart *hu = tty->disc_data;
529 struct hci_dev *hdev;
531 BT_DBG("tty %p", tty);
533 /* Detach from the tty */
534 tty->disc_data = NULL;
541 hci_uart_close(hdev);
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);
548 cancel_work_sync(&hu->init_ready);
549 cancel_work_sync(&hu->write_work);
552 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
553 hci_unregister_dev(hdev);
556 hu->proto->close(hu);
558 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
560 percpu_free_rwsem(&hu->proto_lock);
565 /* hci_uart_tty_wakeup()
567 * Callback for transmit wakeup. Called when low level
568 * device driver can accept more send data.
570 * Arguments: tty pointer to associated tty instance data
573 static void hci_uart_tty_wakeup(struct tty_struct *tty)
575 struct hci_uart *hu = tty->disc_data;
582 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
587 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
588 hci_uart_tx_wakeup(hu);
591 /* hci_uart_tty_receive()
593 * Called by tty low level driver when receive data is
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
603 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
604 char *flags, int count)
606 struct hci_uart *hu = tty->disc_data;
608 if (!hu || tty != hu->tty)
611 percpu_down_read(&hu->proto_lock);
613 if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
614 percpu_up_read(&hu->proto_lock);
618 /* It does not need a lock here as it is already protected by a mutex in
621 hu->proto->recv(hu, data, count);
622 percpu_up_read(&hu->proto_lock);
625 hu->hdev->stat.byte_rx += count;
630 static int hci_uart_register_dev(struct hci_uart *hu)
632 struct hci_dev *hdev;
637 /* Initialize and register HCI device */
638 hdev = hci_alloc_dev();
640 BT_ERR("Can't allocate HCI device");
646 hdev->bus = HCI_UART;
647 hci_set_drvdata(hdev, hu);
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.
653 if (hu->proto->setup)
654 hdev->manufacturer = hu->proto->manufacturer;
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);
663 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
664 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
666 if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
667 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
669 if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
670 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
672 if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
673 hdev->dev_type = HCI_AMP;
675 hdev->dev_type = HCI_PRIMARY;
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.
680 err = hu->proto->open(hu);
687 if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
690 if (hci_register_dev(hdev) < 0) {
691 BT_ERR("Can't register HCI device");
692 hu->proto->close(hu);
698 set_bit(HCI_UART_REGISTERED, &hu->flags);
703 static int hci_uart_set_proto(struct hci_uart *hu, int id)
705 const struct hci_uart_proto *p;
708 p = hci_uart_get_proto(id);
710 return -EPROTONOSUPPORT;
714 err = hci_uart_register_dev(hu);
719 set_bit(HCI_UART_PROTO_READY, &hu->flags);
723 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
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);
732 if (flags & ~valid_flags)
735 hu->hdev_flags = flags;
740 /* hci_uart_tty_ioctl()
742 * Process IOCTL system call for the tty device.
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)
751 * Return Value: Command dependent
753 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
754 unsigned int cmd, unsigned long arg)
756 struct hci_uart *hu = tty->disc_data;
761 /* Verify the status of the device */
766 case HCIUARTSETPROTO:
767 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
768 err = hci_uart_set_proto(hu, arg);
770 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
775 case HCIUARTGETPROTO:
776 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
782 case HCIUARTGETDEVICE:
783 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
789 case HCIUARTSETFLAGS:
790 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
793 err = hci_uart_set_flags(hu, arg);
796 case HCIUARTGETFLAGS:
797 err = hu->hdev_flags;
801 err = n_tty_ioctl_helper(tty, file, cmd, arg);
809 * We don't provide read/write/poll interface for user space.
811 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
812 unsigned char __user *buf, size_t nr)
817 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
818 const unsigned char *data, size_t count)
823 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
824 struct file *filp, poll_table *wait)
829 static int __init hci_uart_init(void)
831 static struct tty_ldisc_ops hci_uart_ldisc;
834 BT_INFO("HCI UART driver ver %s", VERSION);
836 /* Register the tty discipline */
838 memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
839 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
840 hci_uart_ldisc.name = "n_hci";
841 hci_uart_ldisc.open = hci_uart_tty_open;
842 hci_uart_ldisc.close = hci_uart_tty_close;
843 hci_uart_ldisc.read = hci_uart_tty_read;
844 hci_uart_ldisc.write = hci_uart_tty_write;
845 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
846 hci_uart_ldisc.poll = hci_uart_tty_poll;
847 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
848 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
849 hci_uart_ldisc.owner = THIS_MODULE;
851 err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
853 BT_ERR("HCI line discipline registration failed. (%d)", err);
857 #ifdef CONFIG_BT_HCIUART_H4
860 #ifdef CONFIG_BT_HCIUART_BCSP
863 #ifdef CONFIG_BT_HCIUART_LL
866 #ifdef CONFIG_BT_HCIUART_ATH3K
869 #ifdef CONFIG_BT_HCIUART_3WIRE
872 #ifdef CONFIG_BT_HCIUART_INTEL
875 #ifdef CONFIG_BT_HCIUART_BCM
878 #ifdef CONFIG_BT_HCIUART_QCA
881 #ifdef CONFIG_BT_HCIUART_AG6XX
884 #ifdef CONFIG_BT_HCIUART_MRVL
891 static void __exit hci_uart_exit(void)
895 #ifdef CONFIG_BT_HCIUART_H4
898 #ifdef CONFIG_BT_HCIUART_BCSP
901 #ifdef CONFIG_BT_HCIUART_LL
904 #ifdef CONFIG_BT_HCIUART_ATH3K
907 #ifdef CONFIG_BT_HCIUART_3WIRE
910 #ifdef CONFIG_BT_HCIUART_INTEL
913 #ifdef CONFIG_BT_HCIUART_BCM
916 #ifdef CONFIG_BT_HCIUART_QCA
919 #ifdef CONFIG_BT_HCIUART_AG6XX
922 #ifdef CONFIG_BT_HCIUART_MRVL
926 /* Release tty registration of line discipline */
927 err = tty_unregister_ldisc(N_HCI);
929 BT_ERR("Can't unregister HCI line discipline (%d)", err);
932 module_init(hci_uart_init);
933 module_exit(hci_uart_exit);
935 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
936 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
937 MODULE_VERSION(VERSION);
938 MODULE_LICENSE("GPL");
939 MODULE_ALIAS_LDISC(N_HCI);