tty: Ldisc revamp
[linux-2.6-block.git] / drivers / bluetooth / hci_ldisc.c
CommitLineData
1da177e4 1/*
1da177e4 2 *
0372a662
MH
3 * Bluetooth HCI UART driver
4 *
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>
8 *
9 *
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.
14 *
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.
19 *
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
23 *
1da177e4 24 */
1da177e4 25
1da177e4
LT
26#include <linux/module.h>
27
28#include <linux/kernel.h>
29#include <linux/init.h>
1da177e4
LT
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>
35
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
44#include <net/bluetooth/bluetooth.h>
45#include <net/bluetooth/hci_core.h>
46
47#include "hci_uart.h"
48
49#ifndef CONFIG_BT_HCIUART_DEBUG
50#undef BT_DBG
51#define BT_DBG( A... )
1da177e4
LT
52#endif
53
0372a662
MH
54#define VERSION "2.2"
55
1da177e4
LT
56static int reset = 0;
57
58static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
59
60int hci_uart_register_proto(struct hci_uart_proto *p)
61{
62 if (p->id >= HCI_UART_MAX_PROTO)
63 return -EINVAL;
64
65 if (hup[p->id])
66 return -EEXIST;
67
68 hup[p->id] = p;
0372a662 69
1da177e4
LT
70 return 0;
71}
72
73int hci_uart_unregister_proto(struct hci_uart_proto *p)
74{
75 if (p->id >= HCI_UART_MAX_PROTO)
76 return -EINVAL;
77
78 if (!hup[p->id])
79 return -EINVAL;
80
81 hup[p->id] = NULL;
0372a662 82
1da177e4
LT
83 return 0;
84}
85
86static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
87{
88 if (id >= HCI_UART_MAX_PROTO)
89 return NULL;
0372a662 90
1da177e4
LT
91 return hup[id];
92}
93
94static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
95{
96 struct hci_dev *hdev = hu->hdev;
0372a662 97
1da177e4
LT
98 /* Update HCI stat counters */
99 switch (pkt_type) {
100 case HCI_COMMAND_PKT:
101 hdev->stat.cmd_tx++;
102 break;
103
104 case HCI_ACLDATA_PKT:
105 hdev->stat.acl_tx++;
106 break;
107
108 case HCI_SCODATA_PKT:
109 hdev->stat.cmd_tx++;
110 break;
111 }
112}
113
114static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
115{
116 struct sk_buff *skb = hu->tx_skb;
0372a662 117
1da177e4
LT
118 if (!skb)
119 skb = hu->proto->dequeue(hu);
120 else
121 hu->tx_skb = NULL;
0372a662 122
1da177e4
LT
123 return skb;
124}
125
126int hci_uart_tx_wakeup(struct hci_uart *hu)
127{
128 struct tty_struct *tty = hu->tty;
129 struct hci_dev *hdev = hu->hdev;
130 struct sk_buff *skb;
0372a662 131
1da177e4
LT
132 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
133 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
134 return 0;
135 }
136
137 BT_DBG("");
138
139restart:
140 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
141
142 while ((skb = hci_uart_dequeue(hu))) {
143 int len;
0372a662 144
1da177e4 145 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
f34d7a5b 146 len = tty->ops->write(tty, skb->data, skb->len);
1da177e4
LT
147 hdev->stat.byte_tx += len;
148
149 skb_pull(skb, len);
150 if (skb->len) {
151 hu->tx_skb = skb;
152 break;
153 }
0372a662 154
0d48d939 155 hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
1da177e4 156 kfree_skb(skb);
0372a662
MH
157 }
158
1da177e4
LT
159 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
160 goto restart;
161
162 clear_bit(HCI_UART_SENDING, &hu->tx_state);
163 return 0;
164}
165
166/* ------- Interface to HCI layer ------ */
167/* Initialize device */
168static int hci_uart_open(struct hci_dev *hdev)
169{
170 BT_DBG("%s %p", hdev->name, hdev);
171
172 /* Nothing to do for UART driver */
173
174 set_bit(HCI_RUNNING, &hdev->flags);
0372a662 175
1da177e4
LT
176 return 0;
177}
178
179/* Reset device */
180static int hci_uart_flush(struct hci_dev *hdev)
181{
182 struct hci_uart *hu = (struct hci_uart *) hdev->driver_data;
183 struct tty_struct *tty = hu->tty;
184
185 BT_DBG("hdev %p tty %p", hdev, tty);
186
187 if (hu->tx_skb) {
188 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
189 }
190
191 /* Flush any pending characters in the driver and discipline. */
192 tty_ldisc_flush(tty);
f34d7a5b 193 tty_driver_flush_buffer(tty);
1da177e4
LT
194
195 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
196 hu->proto->flush(hu);
197
198 return 0;
199}
200
201/* Close device */
202static int hci_uart_close(struct hci_dev *hdev)
203{
204 BT_DBG("hdev %p", hdev);
205
206 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
207 return 0;
208
209 hci_uart_flush(hdev);
3611f4d2 210 hdev->flush = NULL;
1da177e4
LT
211 return 0;
212}
213
214/* Send frames from HCI layer */
215static int hci_uart_send_frame(struct sk_buff *skb)
216{
217 struct hci_dev* hdev = (struct hci_dev *) skb->dev;
218 struct tty_struct *tty;
219 struct hci_uart *hu;
220
221 if (!hdev) {
222 BT_ERR("Frame for uknown device (hdev=NULL)");
223 return -ENODEV;
224 }
225
226 if (!test_bit(HCI_RUNNING, &hdev->flags))
227 return -EBUSY;
228
229 hu = (struct hci_uart *) hdev->driver_data;
230 tty = hu->tty;
231
0d48d939 232 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
1da177e4
LT
233
234 hu->proto->enqueue(hu, skb);
235
236 hci_uart_tx_wakeup(hu);
0372a662 237
1da177e4
LT
238 return 0;
239}
240
241static void hci_uart_destruct(struct hci_dev *hdev)
242{
0372a662
MH
243 if (!hdev)
244 return;
1da177e4
LT
245
246 BT_DBG("%s", hdev->name);
7785162c 247 kfree(hdev->driver_data);
1da177e4
LT
248}
249
250/* ------ LDISC part ------ */
251/* hci_uart_tty_open
252 *
253 * Called when line discipline changed to HCI_UART.
254 *
255 * Arguments:
256 * tty pointer to tty info structure
257 * Return Value:
258 * 0 if success, otherwise error code
259 */
260static int hci_uart_tty_open(struct tty_struct *tty)
261{
262 struct hci_uart *hu = (void *) tty->disc_data;
263
264 BT_DBG("tty %p", tty);
265
266 if (hu)
267 return -EEXIST;
268
089b1dbb 269 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
7785162c 270 BT_ERR("Can't allocate control structure");
1da177e4
LT
271 return -ENFILE;
272 }
0372a662 273
1da177e4
LT
274 tty->disc_data = hu;
275 hu->tty = tty;
33f0f88f 276 tty->receive_room = 65536;
1da177e4
LT
277
278 spin_lock_init(&hu->rx_lock);
279
280 /* Flush any pending characters in the driver and line discipline. */
0372a662 281
1da177e4
LT
282 /* FIXME: why is this needed. Note don't use ldisc_ref here as the
283 open path is before the ldisc is referencable */
0372a662 284
a352def2
AC
285 if (tty->ldisc.ops->flush_buffer)
286 tty->ldisc.ops->flush_buffer(tty);
f34d7a5b 287 tty_driver_flush_buffer(tty);
1da177e4
LT
288
289 return 0;
290}
291
292/* hci_uart_tty_close()
293 *
294 * Called when the line discipline is changed to something
295 * else, the tty is closed, or the tty detects a hangup.
296 */
297static void hci_uart_tty_close(struct tty_struct *tty)
298{
299 struct hci_uart *hu = (void *)tty->disc_data;
300
301 BT_DBG("tty %p", tty);
302
303 /* Detach from the tty */
304 tty->disc_data = NULL;
305
306 if (hu) {
307 struct hci_dev *hdev = hu->hdev;
22ad4203
MH
308
309 if (hdev)
310 hci_uart_close(hdev);
1da177e4
LT
311
312 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
313 hu->proto->close(hu);
314 hci_unregister_dev(hdev);
315 hci_free_dev(hdev);
316 }
317 }
318}
319
320/* hci_uart_tty_wakeup()
321 *
322 * Callback for transmit wakeup. Called when low level
323 * device driver can accept more send data.
324 *
325 * Arguments: tty pointer to associated tty instance data
326 * Return Value: None
327 */
328static void hci_uart_tty_wakeup(struct tty_struct *tty)
329{
330 struct hci_uart *hu = (void *)tty->disc_data;
331
332 BT_DBG("");
333
334 if (!hu)
335 return;
336
337 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
338
339 if (tty != hu->tty)
340 return;
341
342 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
343 hci_uart_tx_wakeup(hu);
344}
345
1da177e4
LT
346/* hci_uart_tty_receive()
347 *
348 * Called by tty low level driver when receive data is
349 * available.
350 *
351 * Arguments: tty pointer to tty isntance data
352 * data pointer to received data
353 * flags pointer to flags for data
354 * count count of received data in bytes
355 *
356 * Return Value: None
357 */
7785162c 358static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
1da177e4
LT
359{
360 struct hci_uart *hu = (void *)tty->disc_data;
0372a662 361
1da177e4
LT
362 if (!hu || tty != hu->tty)
363 return;
364
365 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
366 return;
0372a662 367
1da177e4
LT
368 spin_lock(&hu->rx_lock);
369 hu->proto->recv(hu, (void *) data, count);
370 hu->hdev->stat.byte_rx += count;
371 spin_unlock(&hu->rx_lock);
372
39c2e60f 373 tty_unthrottle(tty);
1da177e4
LT
374}
375
376static int hci_uart_register_dev(struct hci_uart *hu)
377{
378 struct hci_dev *hdev;
379
380 BT_DBG("");
381
382 /* Initialize and register HCI device */
383 hdev = hci_alloc_dev();
384 if (!hdev) {
385 BT_ERR("Can't allocate HCI device");
386 return -ENOMEM;
387 }
388
389 hu->hdev = hdev;
390
391 hdev->type = HCI_UART;
392 hdev->driver_data = hu;
393
394 hdev->open = hci_uart_open;
395 hdev->close = hci_uart_close;
396 hdev->flush = hci_uart_flush;
397 hdev->send = hci_uart_send_frame;
398 hdev->destruct = hci_uart_destruct;
399
400 hdev->owner = THIS_MODULE;
401
402 if (reset)
403 set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);
404
405 if (hci_register_dev(hdev) < 0) {
406 BT_ERR("Can't register HCI device");
407 hci_free_dev(hdev);
408 return -ENODEV;
409 }
410
411 return 0;
412}
413
414static int hci_uart_set_proto(struct hci_uart *hu, int id)
415{
416 struct hci_uart_proto *p;
0372a662
MH
417 int err;
418
1da177e4
LT
419 p = hci_uart_get_proto(id);
420 if (!p)
421 return -EPROTONOSUPPORT;
422
423 err = p->open(hu);
424 if (err)
425 return err;
426
427 hu->proto = p;
428
429 err = hci_uart_register_dev(hu);
430 if (err) {
431 p->close(hu);
432 return err;
433 }
0372a662 434
1da177e4
LT
435 return 0;
436}
437
438/* hci_uart_tty_ioctl()
439 *
440 * Process IOCTL system call for the tty device.
441 *
442 * Arguments:
443 *
444 * tty pointer to tty instance data
445 * file pointer to open file object for device
446 * cmd IOCTL command code
447 * arg argument for IOCTL call (cmd dependent)
448 *
449 * Return Value: Command dependent
450 */
451static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
0372a662 452 unsigned int cmd, unsigned long arg)
1da177e4
LT
453{
454 struct hci_uart *hu = (void *)tty->disc_data;
455 int err = 0;
456
457 BT_DBG("");
458
459 /* Verify the status of the device */
460 if (!hu)
461 return -EBADF;
462
463 switch (cmd) {
464 case HCIUARTSETPROTO:
465 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
466 err = hci_uart_set_proto(hu, arg);
467 if (err) {
468 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
469 return err;
470 }
471 tty->low_latency = 1;
0372a662 472 } else
1da177e4 473 return -EBUSY;
c33be3c3 474 break;
1da177e4
LT
475
476 case HCIUARTGETPROTO:
477 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
478 return hu->proto->id;
479 return -EUNATCH;
0372a662 480
d2158744
MH
481 case HCIUARTGETDEVICE:
482 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
483 return hu->hdev->id;
484 return -EUNATCH;
485
1da177e4
LT
486 default:
487 err = n_tty_ioctl(tty, file, cmd, arg);
488 break;
489 };
490
491 return err;
492}
493
494/*
495 * We don't provide read/write/poll interface for user space.
496 */
0372a662
MH
497static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
498 unsigned char __user *buf, size_t nr)
1da177e4
LT
499{
500 return 0;
501}
0372a662
MH
502
503static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
504 const unsigned char *data, size_t count)
1da177e4
LT
505{
506 return 0;
507}
0372a662
MH
508
509static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
510 struct file *filp, poll_table *wait)
1da177e4
LT
511{
512 return 0;
513}
514
1da177e4
LT
515static int __init hci_uart_init(void)
516{
a352def2 517 static struct tty_ldisc_ops hci_uart_ldisc;
1da177e4
LT
518 int err;
519
520 BT_INFO("HCI UART driver ver %s", VERSION);
521
522 /* Register the tty discipline */
523
524 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
0372a662
MH
525 hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
526 hci_uart_ldisc.name = "n_hci";
527 hci_uart_ldisc.open = hci_uart_tty_open;
528 hci_uart_ldisc.close = hci_uart_tty_close;
529 hci_uart_ldisc.read = hci_uart_tty_read;
530 hci_uart_ldisc.write = hci_uart_tty_write;
531 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
532 hci_uart_ldisc.poll = hci_uart_tty_poll;
0372a662
MH
533 hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
534 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
535 hci_uart_ldisc.owner = THIS_MODULE;
1da177e4
LT
536
537 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
538 BT_ERR("HCI line discipline registration failed. (%d)", err);
539 return err;
540 }
541
542#ifdef CONFIG_BT_HCIUART_H4
543 h4_init();
544#endif
545#ifdef CONFIG_BT_HCIUART_BCSP
546 bcsp_init();
547#endif
166d2f6a
OBC
548#ifdef CONFIG_BT_HCIUART_LL
549 ll_init();
550#endif
551
1da177e4
LT
552 return 0;
553}
554
555static void __exit hci_uart_exit(void)
556{
557 int err;
558
559#ifdef CONFIG_BT_HCIUART_H4
560 h4_deinit();
561#endif
562#ifdef CONFIG_BT_HCIUART_BCSP
563 bcsp_deinit();
564#endif
166d2f6a
OBC
565#ifdef CONFIG_BT_HCIUART_LL
566 ll_deinit();
567#endif
1da177e4
LT
568
569 /* Release tty registration of line discipline */
64ccd715 570 if ((err = tty_unregister_ldisc(N_HCI)))
1da177e4
LT
571 BT_ERR("Can't unregister HCI line discipline (%d)", err);
572}
573
574module_init(hci_uart_init);
575module_exit(hci_uart_exit);
576
577module_param(reset, bool, 0644);
578MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
579
580MODULE_AUTHOR("Maxim Krasnyansky <maxk@qualcomm.com>, Marcel Holtmann <marcel@holtmann.org>");
581MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
582MODULE_VERSION(VERSION);
583MODULE_LICENSE("GPL");
584MODULE_ALIAS_LDISC(N_HCI);