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>
44 #include <net/bluetooth/bluetooth.h>
45 #include <net/bluetooth/hci_core.h>
51 static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
53 int hci_uart_register_proto(struct hci_uart_proto *p)
55 if (p->id >= HCI_UART_MAX_PROTO)
66 int hci_uart_unregister_proto(struct hci_uart_proto *p)
68 if (p->id >= HCI_UART_MAX_PROTO)
79 static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
81 if (id >= HCI_UART_MAX_PROTO)
87 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
89 struct hci_dev *hdev = hu->hdev;
91 /* Update HCI stat counters */
101 case HCI_SCODATA_PKT:
107 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
109 struct sk_buff *skb = hu->tx_skb;
112 skb = hu->proto->dequeue(hu);
119 int hci_uart_tx_wakeup(struct hci_uart *hu)
121 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
122 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
128 schedule_work(&hu->write_work);
133 static void hci_uart_write_work(struct work_struct *work)
135 struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
136 struct tty_struct *tty = hu->tty;
137 struct hci_dev *hdev = hu->hdev;
140 /* REVISIT: should we cope with bad skbs or ->write() returning
145 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
147 while ((skb = hci_uart_dequeue(hu))) {
150 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
151 len = tty->ops->write(tty, skb->data, skb->len);
152 hdev->stat.byte_tx += len;
160 hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
164 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
167 clear_bit(HCI_UART_SENDING, &hu->tx_state);
170 static void hci_uart_init_work(struct work_struct *work)
172 struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
175 if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
178 err = hci_register_dev(hu->hdev);
180 BT_ERR("Can't register HCI device");
181 hci_free_dev(hu->hdev);
183 hu->proto->close(hu);
186 set_bit(HCI_UART_REGISTERED, &hu->flags);
189 int hci_uart_init_ready(struct hci_uart *hu)
191 if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
194 schedule_work(&hu->init_ready);
199 /* ------- Interface to HCI layer ------ */
200 /* Initialize device */
201 static int hci_uart_open(struct hci_dev *hdev)
203 BT_DBG("%s %p", hdev->name, hdev);
205 /* Nothing to do for UART driver */
207 set_bit(HCI_RUNNING, &hdev->flags);
213 static int hci_uart_flush(struct hci_dev *hdev)
215 struct hci_uart *hu = hci_get_drvdata(hdev);
216 struct tty_struct *tty = hu->tty;
218 BT_DBG("hdev %p tty %p", hdev, tty);
221 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
224 /* Flush any pending characters in the driver and discipline. */
225 tty_ldisc_flush(tty);
226 tty_driver_flush_buffer(tty);
228 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
229 hu->proto->flush(hu);
235 static int hci_uart_close(struct hci_dev *hdev)
237 BT_DBG("hdev %p", hdev);
239 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
242 hci_uart_flush(hdev);
247 /* Send frames from HCI layer */
248 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
250 struct hci_uart *hu = hci_get_drvdata(hdev);
252 if (!test_bit(HCI_RUNNING, &hdev->flags))
255 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
257 hu->proto->enqueue(hu, skb);
259 hci_uart_tx_wakeup(hu);
264 /* ------ LDISC part ------ */
267 * Called when line discipline changed to HCI_UART.
270 * tty pointer to tty info structure
272 * 0 if success, otherwise error code
274 static int hci_uart_tty_open(struct tty_struct *tty)
278 BT_DBG("tty %p", tty);
280 /* Error if the tty has no write op instead of leaving an exploitable
282 if (tty->ops->write == NULL)
285 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
286 BT_ERR("Can't allocate control structure");
292 tty->receive_room = 65536;
294 INIT_WORK(&hu->init_ready, hci_uart_init_work);
295 INIT_WORK(&hu->write_work, hci_uart_write_work);
297 spin_lock_init(&hu->rx_lock);
299 /* Flush any pending characters in the driver and line discipline. */
301 /* FIXME: why is this needed. Note don't use ldisc_ref here as the
302 open path is before the ldisc is referencable */
304 if (tty->ldisc->ops->flush_buffer)
305 tty->ldisc->ops->flush_buffer(tty);
306 tty_driver_flush_buffer(tty);
311 /* hci_uart_tty_close()
313 * Called when the line discipline is changed to something
314 * else, the tty is closed, or the tty detects a hangup.
316 static void hci_uart_tty_close(struct tty_struct *tty)
318 struct hci_uart *hu = (void *)tty->disc_data;
319 struct hci_dev *hdev;
321 BT_DBG("tty %p", tty);
323 /* Detach from the tty */
324 tty->disc_data = NULL;
331 hci_uart_close(hdev);
333 cancel_work_sync(&hu->write_work);
335 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
337 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
338 hci_unregister_dev(hdev);
341 hu->proto->close(hu);
347 /* hci_uart_tty_wakeup()
349 * Callback for transmit wakeup. Called when low level
350 * device driver can accept more send data.
352 * Arguments: tty pointer to associated tty instance data
355 static void hci_uart_tty_wakeup(struct tty_struct *tty)
357 struct hci_uart *hu = (void *)tty->disc_data;
364 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
369 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
370 hci_uart_tx_wakeup(hu);
373 /* hci_uart_tty_receive()
375 * Called by tty low level driver when receive data is
378 * Arguments: tty pointer to tty isntance data
379 * data pointer to received data
380 * flags pointer to flags for data
381 * count count of received data in bytes
385 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
387 struct hci_uart *hu = (void *)tty->disc_data;
389 if (!hu || tty != hu->tty)
392 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
395 spin_lock(&hu->rx_lock);
396 hu->proto->recv(hu, (void *) data, count);
399 hu->hdev->stat.byte_rx += count;
401 spin_unlock(&hu->rx_lock);
406 static int hci_uart_register_dev(struct hci_uart *hu)
408 struct hci_dev *hdev;
412 /* Initialize and register HCI device */
413 hdev = hci_alloc_dev();
415 BT_ERR("Can't allocate HCI device");
421 hdev->bus = HCI_UART;
422 hci_set_drvdata(hdev, hu);
424 hdev->open = hci_uart_open;
425 hdev->close = hci_uart_close;
426 hdev->flush = hci_uart_flush;
427 hdev->send = hci_uart_send_frame;
428 SET_HCIDEV_DEV(hdev, hu->tty->dev);
430 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
431 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
433 if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
434 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
436 if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
437 hdev->dev_type = HCI_AMP;
439 hdev->dev_type = HCI_BREDR;
441 if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
444 if (hci_register_dev(hdev) < 0) {
445 BT_ERR("Can't register HCI device");
450 set_bit(HCI_UART_REGISTERED, &hu->flags);
455 static int hci_uart_set_proto(struct hci_uart *hu, int id)
457 struct hci_uart_proto *p;
460 p = hci_uart_get_proto(id);
462 return -EPROTONOSUPPORT;
470 err = hci_uart_register_dev(hu);
479 /* hci_uart_tty_ioctl()
481 * Process IOCTL system call for the tty device.
485 * tty pointer to tty instance data
486 * file pointer to open file object for device
487 * cmd IOCTL command code
488 * arg argument for IOCTL call (cmd dependent)
490 * Return Value: Command dependent
492 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
493 unsigned int cmd, unsigned long arg)
495 struct hci_uart *hu = (void *)tty->disc_data;
500 /* Verify the status of the device */
505 case HCIUARTSETPROTO:
506 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
507 err = hci_uart_set_proto(hu, arg);
509 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
516 case HCIUARTGETPROTO:
517 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
518 return hu->proto->id;
521 case HCIUARTGETDEVICE:
522 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
526 case HCIUARTSETFLAGS:
527 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
529 hu->hdev_flags = arg;
532 case HCIUARTGETFLAGS:
533 return hu->hdev_flags;
536 err = n_tty_ioctl_helper(tty, file, cmd, arg);
544 * We don't provide read/write/poll interface for user space.
546 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
547 unsigned char __user *buf, size_t nr)
552 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
553 const unsigned char *data, size_t count)
558 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
559 struct file *filp, poll_table *wait)
564 static int __init hci_uart_init(void)
566 static struct tty_ldisc_ops hci_uart_ldisc;
569 BT_INFO("HCI UART driver ver %s", VERSION);
571 /* Register the tty discipline */
573 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
574 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
575 hci_uart_ldisc.name = "n_hci";
576 hci_uart_ldisc.open = hci_uart_tty_open;
577 hci_uart_ldisc.close = hci_uart_tty_close;
578 hci_uart_ldisc.read = hci_uart_tty_read;
579 hci_uart_ldisc.write = hci_uart_tty_write;
580 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
581 hci_uart_ldisc.poll = hci_uart_tty_poll;
582 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
583 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
584 hci_uart_ldisc.owner = THIS_MODULE;
586 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
587 BT_ERR("HCI line discipline registration failed. (%d)", err);
591 #ifdef CONFIG_BT_HCIUART_H4
594 #ifdef CONFIG_BT_HCIUART_BCSP
597 #ifdef CONFIG_BT_HCIUART_LL
600 #ifdef CONFIG_BT_HCIUART_ATH3K
603 #ifdef CONFIG_BT_HCIUART_3WIRE
610 static void __exit hci_uart_exit(void)
614 #ifdef CONFIG_BT_HCIUART_H4
617 #ifdef CONFIG_BT_HCIUART_BCSP
620 #ifdef CONFIG_BT_HCIUART_LL
623 #ifdef CONFIG_BT_HCIUART_ATH3K
626 #ifdef CONFIG_BT_HCIUART_3WIRE
630 /* Release tty registration of line discipline */
631 if ((err = tty_unregister_ldisc(N_HCI)))
632 BT_ERR("Can't unregister HCI line discipline (%d)", err);
635 module_init(hci_uart_init);
636 module_exit(hci_uart_exit);
638 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
639 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
640 MODULE_VERSION(VERSION);
641 MODULE_LICENSE("GPL");
642 MODULE_ALIAS_LDISC(N_HCI);