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 sk_buff *skb)
250 struct hci_dev* hdev = (struct hci_dev *) skb->dev;
254 BT_ERR("Frame for unknown device (hdev=NULL)");
258 if (!test_bit(HCI_RUNNING, &hdev->flags))
261 hu = hci_get_drvdata(hdev);
263 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
265 hu->proto->enqueue(hu, skb);
267 hci_uart_tx_wakeup(hu);
272 /* ------ LDISC part ------ */
275 * Called when line discipline changed to HCI_UART.
278 * tty pointer to tty info structure
280 * 0 if success, otherwise error code
282 static int hci_uart_tty_open(struct tty_struct *tty)
286 BT_DBG("tty %p", tty);
288 /* Error if the tty has no write op instead of leaving an exploitable
290 if (tty->ops->write == NULL)
293 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
294 BT_ERR("Can't allocate control structure");
300 tty->receive_room = 65536;
302 INIT_WORK(&hu->init_ready, hci_uart_init_work);
303 INIT_WORK(&hu->write_work, hci_uart_write_work);
305 spin_lock_init(&hu->rx_lock);
307 /* Flush any pending characters in the driver and line discipline. */
309 /* FIXME: why is this needed. Note don't use ldisc_ref here as the
310 open path is before the ldisc is referencable */
312 if (tty->ldisc->ops->flush_buffer)
313 tty->ldisc->ops->flush_buffer(tty);
314 tty_driver_flush_buffer(tty);
319 /* hci_uart_tty_close()
321 * Called when the line discipline is changed to something
322 * else, the tty is closed, or the tty detects a hangup.
324 static void hci_uart_tty_close(struct tty_struct *tty)
326 struct hci_uart *hu = (void *)tty->disc_data;
327 struct hci_dev *hdev;
329 BT_DBG("tty %p", tty);
331 /* Detach from the tty */
332 tty->disc_data = NULL;
339 hci_uart_close(hdev);
341 cancel_work_sync(&hu->write_work);
343 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
345 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
346 hci_unregister_dev(hdev);
349 hu->proto->close(hu);
355 /* hci_uart_tty_wakeup()
357 * Callback for transmit wakeup. Called when low level
358 * device driver can accept more send data.
360 * Arguments: tty pointer to associated tty instance data
363 static void hci_uart_tty_wakeup(struct tty_struct *tty)
365 struct hci_uart *hu = (void *)tty->disc_data;
372 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
377 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
378 hci_uart_tx_wakeup(hu);
381 /* hci_uart_tty_receive()
383 * Called by tty low level driver when receive data is
386 * Arguments: tty pointer to tty isntance data
387 * data pointer to received data
388 * flags pointer to flags for data
389 * count count of received data in bytes
393 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
395 struct hci_uart *hu = (void *)tty->disc_data;
397 if (!hu || tty != hu->tty)
400 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
403 spin_lock(&hu->rx_lock);
404 hu->proto->recv(hu, (void *) data, count);
407 hu->hdev->stat.byte_rx += count;
409 spin_unlock(&hu->rx_lock);
414 static int hci_uart_register_dev(struct hci_uart *hu)
416 struct hci_dev *hdev;
420 /* Initialize and register HCI device */
421 hdev = hci_alloc_dev();
423 BT_ERR("Can't allocate HCI device");
429 hdev->bus = HCI_UART;
430 hci_set_drvdata(hdev, hu);
432 hdev->open = hci_uart_open;
433 hdev->close = hci_uart_close;
434 hdev->flush = hci_uart_flush;
435 hdev->send = hci_uart_send_frame;
436 SET_HCIDEV_DEV(hdev, hu->tty->dev);
438 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
439 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
441 if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
442 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
444 if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
445 hdev->dev_type = HCI_AMP;
447 hdev->dev_type = HCI_BREDR;
449 if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
452 if (hci_register_dev(hdev) < 0) {
453 BT_ERR("Can't register HCI device");
458 set_bit(HCI_UART_REGISTERED, &hu->flags);
463 static int hci_uart_set_proto(struct hci_uart *hu, int id)
465 struct hci_uart_proto *p;
468 p = hci_uart_get_proto(id);
470 return -EPROTONOSUPPORT;
478 err = hci_uart_register_dev(hu);
487 /* hci_uart_tty_ioctl()
489 * Process IOCTL system call for the tty device.
493 * tty pointer to tty instance data
494 * file pointer to open file object for device
495 * cmd IOCTL command code
496 * arg argument for IOCTL call (cmd dependent)
498 * Return Value: Command dependent
500 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
501 unsigned int cmd, unsigned long arg)
503 struct hci_uart *hu = (void *)tty->disc_data;
508 /* Verify the status of the device */
513 case HCIUARTSETPROTO:
514 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
515 err = hci_uart_set_proto(hu, arg);
517 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
524 case HCIUARTGETPROTO:
525 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
526 return hu->proto->id;
529 case HCIUARTGETDEVICE:
530 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
534 case HCIUARTSETFLAGS:
535 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
537 hu->hdev_flags = arg;
540 case HCIUARTGETFLAGS:
541 return hu->hdev_flags;
544 err = n_tty_ioctl_helper(tty, file, cmd, arg);
552 * We don't provide read/write/poll interface for user space.
554 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
555 unsigned char __user *buf, size_t nr)
560 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
561 const unsigned char *data, size_t count)
566 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
567 struct file *filp, poll_table *wait)
572 static int __init hci_uart_init(void)
574 static struct tty_ldisc_ops hci_uart_ldisc;
577 BT_INFO("HCI UART driver ver %s", VERSION);
579 /* Register the tty discipline */
581 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
582 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
583 hci_uart_ldisc.name = "n_hci";
584 hci_uart_ldisc.open = hci_uart_tty_open;
585 hci_uart_ldisc.close = hci_uart_tty_close;
586 hci_uart_ldisc.read = hci_uart_tty_read;
587 hci_uart_ldisc.write = hci_uart_tty_write;
588 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
589 hci_uart_ldisc.poll = hci_uart_tty_poll;
590 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
591 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
592 hci_uart_ldisc.owner = THIS_MODULE;
594 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
595 BT_ERR("HCI line discipline registration failed. (%d)", err);
599 #ifdef CONFIG_BT_HCIUART_H4
602 #ifdef CONFIG_BT_HCIUART_BCSP
605 #ifdef CONFIG_BT_HCIUART_LL
608 #ifdef CONFIG_BT_HCIUART_ATH3K
611 #ifdef CONFIG_BT_HCIUART_3WIRE
618 static void __exit hci_uart_exit(void)
622 #ifdef CONFIG_BT_HCIUART_H4
625 #ifdef CONFIG_BT_HCIUART_BCSP
628 #ifdef CONFIG_BT_HCIUART_LL
631 #ifdef CONFIG_BT_HCIUART_ATH3K
634 #ifdef CONFIG_BT_HCIUART_3WIRE
638 /* Release tty registration of line discipline */
639 if ((err = tty_unregister_ldisc(N_HCI)))
640 BT_ERR("Can't unregister HCI line discipline (%d)", err);
643 module_init(hci_uart_init);
644 module_exit(hci_uart_exit);
646 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
647 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
648 MODULE_VERSION(VERSION);
649 MODULE_LICENSE("GPL");
650 MODULE_ALIAS_LDISC(N_HCI);