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>
53 static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
55 int hci_uart_register_proto(struct hci_uart_proto *p)
57 if (p->id >= HCI_UART_MAX_PROTO)
68 int hci_uart_unregister_proto(struct hci_uart_proto *p)
70 if (p->id >= HCI_UART_MAX_PROTO)
81 static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
83 if (id >= HCI_UART_MAX_PROTO)
89 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
91 struct hci_dev *hdev = hu->hdev;
93 /* Update HCI stat counters */
103 case HCI_SCODATA_PKT:
109 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
111 struct sk_buff *skb = hu->tx_skb;
114 skb = hu->proto->dequeue(hu);
121 int hci_uart_tx_wakeup(struct hci_uart *hu)
123 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
124 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
130 schedule_work(&hu->write_work);
135 static void hci_uart_write_work(struct work_struct *work)
137 struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
138 struct tty_struct *tty = hu->tty;
139 struct hci_dev *hdev = hu->hdev;
142 /* REVISIT: should we cope with bad skbs or ->write() returning
147 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
149 while ((skb = hci_uart_dequeue(hu))) {
152 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
153 len = tty->ops->write(tty, skb->data, skb->len);
154 hdev->stat.byte_tx += len;
162 hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
166 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
169 clear_bit(HCI_UART_SENDING, &hu->tx_state);
172 /* ------- Interface to HCI layer ------ */
173 /* Initialize device */
174 static int hci_uart_open(struct hci_dev *hdev)
176 BT_DBG("%s %p", hdev->name, hdev);
178 /* Nothing to do for UART driver */
180 set_bit(HCI_RUNNING, &hdev->flags);
186 static int hci_uart_flush(struct hci_dev *hdev)
188 struct hci_uart *hu = (struct hci_uart *) hdev->driver_data;
189 struct tty_struct *tty = hu->tty;
191 BT_DBG("hdev %p tty %p", hdev, tty);
194 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
197 /* Flush any pending characters in the driver and discipline. */
198 tty_ldisc_flush(tty);
199 tty_driver_flush_buffer(tty);
201 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
202 hu->proto->flush(hu);
208 static int hci_uart_close(struct hci_dev *hdev)
210 BT_DBG("hdev %p", hdev);
212 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
215 hci_uart_flush(hdev);
220 /* Send frames from HCI layer */
221 static int hci_uart_send_frame(struct sk_buff *skb)
223 struct hci_dev* hdev = (struct hci_dev *) skb->dev;
227 BT_ERR("Frame for unknown device (hdev=NULL)");
231 if (!test_bit(HCI_RUNNING, &hdev->flags))
234 hu = (struct hci_uart *) hdev->driver_data;
236 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
238 hu->proto->enqueue(hu, skb);
240 hci_uart_tx_wakeup(hu);
245 static void hci_uart_destruct(struct hci_dev *hdev)
250 BT_DBG("%s", hdev->name);
253 /* ------ LDISC part ------ */
256 * Called when line discipline changed to HCI_UART.
259 * tty pointer to tty info structure
261 * 0 if success, otherwise error code
263 static int hci_uart_tty_open(struct tty_struct *tty)
265 struct hci_uart *hu = (void *) tty->disc_data;
267 BT_DBG("tty %p", tty);
269 /* FIXME: This btw is bogus, nothing requires the old ldisc to clear
274 /* Error if the tty has no write op instead of leaving an exploitable
276 if (tty->ops->write == NULL)
279 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
280 BT_ERR("Can't allocate control structure");
286 tty->receive_room = 65536;
288 INIT_WORK(&hu->write_work, hci_uart_write_work);
290 spin_lock_init(&hu->rx_lock);
292 /* Flush any pending characters in the driver and line discipline. */
294 /* FIXME: why is this needed. Note don't use ldisc_ref here as the
295 open path is before the ldisc is referencable */
297 if (tty->ldisc->ops->flush_buffer)
298 tty->ldisc->ops->flush_buffer(tty);
299 tty_driver_flush_buffer(tty);
304 /* hci_uart_tty_close()
306 * Called when the line discipline is changed to something
307 * else, the tty is closed, or the tty detects a hangup.
309 static void hci_uart_tty_close(struct tty_struct *tty)
311 struct hci_uart *hu = (void *)tty->disc_data;
313 BT_DBG("tty %p", tty);
315 /* Detach from the tty */
316 tty->disc_data = NULL;
319 struct hci_dev *hdev = hu->hdev;
322 hci_uart_close(hdev);
324 cancel_work_sync(&hu->write_work);
326 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
328 hci_unregister_dev(hdev);
331 hu->proto->close(hu);
337 /* hci_uart_tty_wakeup()
339 * Callback for transmit wakeup. Called when low level
340 * device driver can accept more send data.
342 * Arguments: tty pointer to associated tty instance data
345 static void hci_uart_tty_wakeup(struct tty_struct *tty)
347 struct hci_uart *hu = (void *)tty->disc_data;
354 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
359 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
360 hci_uart_tx_wakeup(hu);
363 /* hci_uart_tty_receive()
365 * Called by tty low level driver when receive data is
368 * Arguments: tty pointer to tty isntance data
369 * data pointer to received data
370 * flags pointer to flags for data
371 * count count of received data in bytes
375 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
377 struct hci_uart *hu = (void *)tty->disc_data;
379 if (!hu || tty != hu->tty)
382 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
385 spin_lock(&hu->rx_lock);
386 hu->proto->recv(hu, (void *) data, count);
387 hu->hdev->stat.byte_rx += count;
388 spin_unlock(&hu->rx_lock);
393 static int hci_uart_register_dev(struct hci_uart *hu)
395 struct hci_dev *hdev;
399 /* Initialize and register HCI device */
400 hdev = hci_alloc_dev();
402 BT_ERR("Can't allocate HCI device");
408 hdev->bus = HCI_UART;
409 hdev->driver_data = hu;
411 hdev->open = hci_uart_open;
412 hdev->close = hci_uart_close;
413 hdev->flush = hci_uart_flush;
414 hdev->send = hci_uart_send_frame;
415 hdev->destruct = hci_uart_destruct;
416 hdev->parent = hu->tty->dev;
418 hdev->owner = THIS_MODULE;
421 set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks);
423 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
424 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
426 if (hci_register_dev(hdev) < 0) {
427 BT_ERR("Can't register HCI device");
435 static int hci_uart_set_proto(struct hci_uart *hu, int id)
437 struct hci_uart_proto *p;
440 p = hci_uart_get_proto(id);
442 return -EPROTONOSUPPORT;
450 err = hci_uart_register_dev(hu);
459 /* hci_uart_tty_ioctl()
461 * Process IOCTL system call for the tty device.
465 * tty pointer to tty instance data
466 * file pointer to open file object for device
467 * cmd IOCTL command code
468 * arg argument for IOCTL call (cmd dependent)
470 * Return Value: Command dependent
472 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
473 unsigned int cmd, unsigned long arg)
475 struct hci_uart *hu = (void *)tty->disc_data;
480 /* Verify the status of the device */
485 case HCIUARTSETPROTO:
486 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
487 err = hci_uart_set_proto(hu, arg);
489 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
496 case HCIUARTGETPROTO:
497 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
498 return hu->proto->id;
501 case HCIUARTGETDEVICE:
502 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
506 case HCIUARTSETFLAGS:
507 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
509 hu->hdev_flags = arg;
512 case HCIUARTGETFLAGS:
513 return hu->hdev_flags;
516 err = n_tty_ioctl_helper(tty, file, cmd, arg);
524 * We don't provide read/write/poll interface for user space.
526 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
527 unsigned char __user *buf, size_t nr)
532 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
533 const unsigned char *data, size_t count)
538 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
539 struct file *filp, poll_table *wait)
544 static int __init hci_uart_init(void)
546 static struct tty_ldisc_ops hci_uart_ldisc;
549 BT_INFO("HCI UART driver ver %s", VERSION);
551 /* Register the tty discipline */
553 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
554 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
555 hci_uart_ldisc.name = "n_hci";
556 hci_uart_ldisc.open = hci_uart_tty_open;
557 hci_uart_ldisc.close = hci_uart_tty_close;
558 hci_uart_ldisc.read = hci_uart_tty_read;
559 hci_uart_ldisc.write = hci_uart_tty_write;
560 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
561 hci_uart_ldisc.poll = hci_uart_tty_poll;
562 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
563 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
564 hci_uart_ldisc.owner = THIS_MODULE;
566 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
567 BT_ERR("HCI line discipline registration failed. (%d)", err);
571 #ifdef CONFIG_BT_HCIUART_H4
574 #ifdef CONFIG_BT_HCIUART_BCSP
577 #ifdef CONFIG_BT_HCIUART_LL
580 #ifdef CONFIG_BT_HCIUART_ATH3K
587 static void __exit hci_uart_exit(void)
591 #ifdef CONFIG_BT_HCIUART_H4
594 #ifdef CONFIG_BT_HCIUART_BCSP
597 #ifdef CONFIG_BT_HCIUART_LL
600 #ifdef CONFIG_BT_HCIUART_ATH3K
604 /* Release tty registration of line discipline */
605 if ((err = tty_unregister_ldisc(N_HCI)))
606 BT_ERR("Can't unregister HCI line discipline (%d)", err);
609 module_init(hci_uart_init);
610 module_exit(hci_uart_exit);
612 module_param(reset, bool, 0644);
613 MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
615 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
616 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
617 MODULE_VERSION(VERSION);
618 MODULE_LICENSE("GPL");
619 MODULE_ALIAS_LDISC(N_HCI);