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 bool reset = 0;
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 struct tty_struct *tty = hu->tty;
124 struct hci_dev *hdev = hu->hdev;
127 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
128 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
135 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
137 while ((skb = hci_uart_dequeue(hu))) {
140 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
141 len = tty->ops->write(tty, skb->data, skb->len);
142 hdev->stat.byte_tx += len;
150 hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
154 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
157 clear_bit(HCI_UART_SENDING, &hu->tx_state);
161 /* ------- Interface to HCI layer ------ */
162 /* Initialize device */
163 static int hci_uart_open(struct hci_dev *hdev)
165 BT_DBG("%s %p", hdev->name, hdev);
167 /* Nothing to do for UART driver */
169 set_bit(HCI_RUNNING, &hdev->flags);
175 static int hci_uart_flush(struct hci_dev *hdev)
177 struct hci_uart *hu = (struct hci_uart *) hdev->driver_data;
178 struct tty_struct *tty = hu->tty;
180 BT_DBG("hdev %p tty %p", hdev, tty);
183 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
186 /* Flush any pending characters in the driver and discipline. */
187 tty_ldisc_flush(tty);
188 tty_driver_flush_buffer(tty);
190 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
191 hu->proto->flush(hu);
197 static int hci_uart_close(struct hci_dev *hdev)
199 BT_DBG("hdev %p", hdev);
201 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
204 hci_uart_flush(hdev);
209 /* Send frames from HCI layer */
210 static int hci_uart_send_frame(struct sk_buff *skb)
212 struct hci_dev* hdev = (struct hci_dev *) skb->dev;
216 BT_ERR("Frame for unknown device (hdev=NULL)");
220 if (!test_bit(HCI_RUNNING, &hdev->flags))
223 hu = (struct hci_uart *) hdev->driver_data;
225 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
227 hu->proto->enqueue(hu, skb);
229 hci_uart_tx_wakeup(hu);
234 static void hci_uart_destruct(struct hci_dev *hdev)
239 BT_DBG("%s", hdev->name);
240 kfree(hdev->driver_data);
243 /* ------ LDISC part ------ */
246 * Called when line discipline changed to HCI_UART.
249 * tty pointer to tty info structure
251 * 0 if success, otherwise error code
253 static int hci_uart_tty_open(struct tty_struct *tty)
255 struct hci_uart *hu = (void *) tty->disc_data;
257 BT_DBG("tty %p", tty);
259 /* FIXME: This btw is bogus, nothing requires the old ldisc to clear
264 /* Error if the tty has no write op instead of leaving an exploitable
266 if (tty->ops->write == NULL)
269 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
270 BT_ERR("Can't allocate control structure");
276 tty->receive_room = 65536;
278 spin_lock_init(&hu->rx_lock);
280 /* Flush any pending characters in the driver and line discipline. */
282 /* FIXME: why is this needed. Note don't use ldisc_ref here as the
283 open path is before the ldisc is referencable */
285 if (tty->ldisc->ops->flush_buffer)
286 tty->ldisc->ops->flush_buffer(tty);
287 tty_driver_flush_buffer(tty);
292 /* hci_uart_tty_close()
294 * Called when the line discipline is changed to something
295 * else, the tty is closed, or the tty detects a hangup.
297 static void hci_uart_tty_close(struct tty_struct *tty)
299 struct hci_uart *hu = (void *)tty->disc_data;
301 BT_DBG("tty %p", tty);
303 /* Detach from the tty */
304 tty->disc_data = NULL;
307 struct hci_dev *hdev = hu->hdev;
310 hci_uart_close(hdev);
312 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
313 hu->proto->close(hu);
315 hci_unregister_dev(hdev);
322 /* hci_uart_tty_wakeup()
324 * Callback for transmit wakeup. Called when low level
325 * device driver can accept more send data.
327 * Arguments: tty pointer to associated tty instance data
330 static void hci_uart_tty_wakeup(struct tty_struct *tty)
332 struct hci_uart *hu = (void *)tty->disc_data;
339 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
344 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
345 hci_uart_tx_wakeup(hu);
348 /* hci_uart_tty_receive()
350 * Called by tty low level driver when receive data is
353 * Arguments: tty pointer to tty isntance data
354 * data pointer to received data
355 * flags pointer to flags for data
356 * count count of received data in bytes
360 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
362 struct hci_uart *hu = (void *)tty->disc_data;
364 if (!hu || tty != hu->tty)
367 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
370 spin_lock(&hu->rx_lock);
371 hu->proto->recv(hu, (void *) data, count);
372 hu->hdev->stat.byte_rx += count;
373 spin_unlock(&hu->rx_lock);
378 static int hci_uart_register_dev(struct hci_uart *hu)
380 struct hci_dev *hdev;
384 /* Initialize and register HCI device */
385 hdev = hci_alloc_dev();
387 BT_ERR("Can't allocate HCI device");
393 hdev->bus = HCI_UART;
394 hdev->driver_data = hu;
396 hdev->open = hci_uart_open;
397 hdev->close = hci_uart_close;
398 hdev->flush = hci_uart_flush;
399 hdev->send = hci_uart_send_frame;
400 hdev->destruct = hci_uart_destruct;
401 hdev->parent = hu->tty->dev;
403 hdev->owner = THIS_MODULE;
406 set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks);
408 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
409 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
411 if (hci_register_dev(hdev) < 0) {
412 BT_ERR("Can't register HCI device");
420 static int hci_uart_set_proto(struct hci_uart *hu, int id)
422 struct hci_uart_proto *p;
425 p = hci_uart_get_proto(id);
427 return -EPROTONOSUPPORT;
435 err = hci_uart_register_dev(hu);
444 /* hci_uart_tty_ioctl()
446 * Process IOCTL system call for the tty device.
450 * tty pointer to tty instance data
451 * file pointer to open file object for device
452 * cmd IOCTL command code
453 * arg argument for IOCTL call (cmd dependent)
455 * Return Value: Command dependent
457 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
458 unsigned int cmd, unsigned long arg)
460 struct hci_uart *hu = (void *)tty->disc_data;
465 /* Verify the status of the device */
470 case HCIUARTSETPROTO:
471 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
472 err = hci_uart_set_proto(hu, arg);
474 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
481 case HCIUARTGETPROTO:
482 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
483 return hu->proto->id;
486 case HCIUARTGETDEVICE:
487 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
491 case HCIUARTSETFLAGS:
492 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
494 hu->hdev_flags = arg;
497 case HCIUARTGETFLAGS:
498 return hu->hdev_flags;
501 err = n_tty_ioctl_helper(tty, file, cmd, arg);
509 * We don't provide read/write/poll interface for user space.
511 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
512 unsigned char __user *buf, size_t nr)
517 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
518 const unsigned char *data, size_t count)
523 static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
524 struct file *filp, poll_table *wait)
529 static int __init hci_uart_init(void)
531 static struct tty_ldisc_ops hci_uart_ldisc;
534 BT_INFO("HCI UART driver ver %s", VERSION);
536 /* Register the tty discipline */
538 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
539 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
540 hci_uart_ldisc.name = "n_hci";
541 hci_uart_ldisc.open = hci_uart_tty_open;
542 hci_uart_ldisc.close = hci_uart_tty_close;
543 hci_uart_ldisc.read = hci_uart_tty_read;
544 hci_uart_ldisc.write = hci_uart_tty_write;
545 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
546 hci_uart_ldisc.poll = hci_uart_tty_poll;
547 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
548 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
549 hci_uart_ldisc.owner = THIS_MODULE;
551 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
552 BT_ERR("HCI line discipline registration failed. (%d)", err);
556 #ifdef CONFIG_BT_HCIUART_H4
559 #ifdef CONFIG_BT_HCIUART_BCSP
562 #ifdef CONFIG_BT_HCIUART_LL
565 #ifdef CONFIG_BT_HCIUART_ATH3K
572 static void __exit hci_uart_exit(void)
576 #ifdef CONFIG_BT_HCIUART_H4
579 #ifdef CONFIG_BT_HCIUART_BCSP
582 #ifdef CONFIG_BT_HCIUART_LL
585 #ifdef CONFIG_BT_HCIUART_ATH3K
589 /* Release tty registration of line discipline */
590 if ((err = tty_unregister_ldisc(N_HCI)))
591 BT_ERR("Can't unregister HCI line discipline (%d)", err);
594 module_init(hci_uart_init);
595 module_exit(hci_uart_exit);
597 module_param(reset, bool, 0644);
598 MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
600 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
601 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
602 MODULE_VERSION(VERSION);
603 MODULE_LICENSE("GPL");
604 MODULE_ALIAS_LDISC(N_HCI);