1/* 2 * 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 * 24 */ 25 26#include <linux/module.h> 27 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> 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#define VERSION "2.2" 50 51static int reset = 0; 52 53static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO]; 54 55int hci_uart_register_proto(struct hci_uart_proto *p) 56{ 57 if (p->id >= HCI_UART_MAX_PROTO) 58 return -EINVAL; 59 60 if (hup[p->id]) 61 return -EEXIST; 62 63 hup[p->id] = p; 64 65 return 0; 66} 67 68int hci_uart_unregister_proto(struct hci_uart_proto *p) 69{ 70 if (p->id >= HCI_UART_MAX_PROTO) 71 return -EINVAL; 72 73 if (!hup[p->id]) 74 return -EINVAL; 75 76 hup[p->id] = NULL; 77 78 return 0; 79} 80 81static struct hci_uart_proto *hci_uart_get_proto(unsigned int id) 82{ 83 if (id >= HCI_UART_MAX_PROTO) 84 return NULL; 85 86 return hup[id]; 87} 88 89static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type) 90{ 91 struct hci_dev *hdev = hu->hdev; 92 93 /* Update HCI stat counters */ 94 switch (pkt_type) { 95 case HCI_COMMAND_PKT: 96 hdev->stat.cmd_tx++; 97 break; 98 99 case HCI_ACLDATA_PKT: 100 hdev->stat.acl_tx++; 101 break; 102 103 case HCI_SCODATA_PKT: 104 hdev->stat.cmd_tx++; 105 break; 106 } 107} 108 109static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu) 110{ 111 struct sk_buff *skb = hu->tx_skb; 112 113 if (!skb) 114 skb = hu->proto->dequeue(hu); 115 else 116 hu->tx_skb = NULL; 117 118 return skb; 119} 120 121int hci_uart_tx_wakeup(struct hci_uart *hu) 122{ 123 struct tty_struct *tty = hu->tty; 124 struct hci_dev *hdev = hu->hdev; 125 struct sk_buff *skb; 126 127 if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) { 128 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state); 129 return 0; 130 } 131 132 BT_DBG(""); 133 134restart: 135 clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state); 136 137 while ((skb = hci_uart_dequeue(hu))) { 138 int len; 139 140 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 141 len = tty->ops->write(tty, skb->data, skb->len); 142 hdev->stat.byte_tx += len; 143 144 skb_pull(skb, len); 145 if (skb->len) { 146 hu->tx_skb = skb; 147 break; 148 } 149 150 hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type); 151 kfree_skb(skb); 152 } 153 154 if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state)) 155 goto restart; 156 157 clear_bit(HCI_UART_SENDING, &hu->tx_state); 158 return 0; 159} 160 161/* ------- Interface to HCI layer ------ */ 162/* Initialize device */ 163static int hci_uart_open(struct hci_dev *hdev) 164{ 165 BT_DBG("%s %p", hdev->name, hdev); 166 167 /* Nothing to do for UART driver */ 168 169 set_bit(HCI_RUNNING, &hdev->flags); 170 171 return 0; 172} 173 174/* Reset device */ 175static int hci_uart_flush(struct hci_dev *hdev) 176{ 177 struct hci_uart *hu = (struct hci_uart *) hdev->driver_data; 178 struct tty_struct *tty = hu->tty; 179 180 BT_DBG("hdev %p tty %p", hdev, tty); 181 182 if (hu->tx_skb) { 183 kfree_skb(hu->tx_skb); hu->tx_skb = NULL; 184 } 185 186 /* Flush any pending characters in the driver and discipline. */ 187 tty_ldisc_flush(tty); 188 tty_driver_flush_buffer(tty); 189 190 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 191 hu->proto->flush(hu); 192 193 return 0; 194} 195 196/* Close device */ 197static int hci_uart_close(struct hci_dev *hdev) 198{ 199 BT_DBG("hdev %p", hdev); 200 201 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags)) 202 return 0; 203 204 hci_uart_flush(hdev); 205 hdev->flush = NULL; 206 return 0; 207} 208 209/* Send frames from HCI layer */ 210static int hci_uart_send_frame(struct sk_buff *skb) 211{ 212 struct hci_dev* hdev = (struct hci_dev *) skb->dev; 213 struct hci_uart *hu; 214 215 if (!hdev) { 216 BT_ERR("Frame for unknown device (hdev=NULL)"); 217 return -ENODEV; 218 } 219 220 if (!test_bit(HCI_RUNNING, &hdev->flags)) 221 return -EBUSY; 222 223 hu = (struct hci_uart *) hdev->driver_data; 224 225 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len); 226 227 hu->proto->enqueue(hu, skb); 228 229 hci_uart_tx_wakeup(hu); 230 231 return 0; 232} 233 234static void hci_uart_destruct(struct hci_dev *hdev) 235{ 236 if (!hdev) 237 return; 238 239 BT_DBG("%s", hdev->name); 240 kfree(hdev->driver_data); 241} 242 243/* ------ LDISC part ------ */ 244/* hci_uart_tty_open 245 * 246 * Called when line discipline changed to HCI_UART. 247 * 248 * Arguments: 249 * tty pointer to tty info structure 250 * Return Value: 251 * 0 if success, otherwise error code 252 */ 253static int hci_uart_tty_open(struct tty_struct *tty) 254{ 255 struct hci_uart *hu = (void *) tty->disc_data; 256 257 BT_DBG("tty %p", tty); 258 259 if (hu) 260 return -EEXIST; 261 262 /* Error if the tty has no write op instead of leaving an exploitable 263 hole */ 264 if (tty->ops->write == NULL) 265 return -EOPNOTSUPP; 266 267 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) { 268 BT_ERR("Can't allocate control structure"); 269 return -ENFILE; 270 } 271 272 tty->disc_data = hu; 273 hu->tty = tty; 274 tty->receive_room = 65536; 275 276 spin_lock_init(&hu->rx_lock); 277 278 /* Flush any pending characters in the driver and line discipline. */ 279 280 281 if (tty->ldisc->ops->flush_buffer) 282 tty->ldisc->ops->flush_buffer(tty); 283 tty_driver_flush_buffer(tty); 284 285 return 0; 286} 287 288/* hci_uart_tty_close() 289 * 290 * Called when the line discipline is changed to something 291 * else, the tty is closed, or the tty detects a hangup. 292 */ 293static void hci_uart_tty_close(struct tty_struct *tty) 294{ 295 struct hci_uart *hu = (void *)tty->disc_data; 296 297 BT_DBG("tty %p", tty); 298 299 /* Detach from the tty */ 300 tty->disc_data = NULL; 301 302 if (hu) { 303 struct hci_dev *hdev = hu->hdev; 304 305 if (hdev) 306 hci_uart_close(hdev); 307 308 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) { 309 hu->proto->close(hu); 310 hci_unregister_dev(hdev); 311 hci_free_dev(hdev); 312 } 313 } 314} 315 316/* hci_uart_tty_wakeup() 317 * 318 * Callback for transmit wakeup. Called when low level 319 * device driver can accept more send data. 320 * 321 * Arguments: tty pointer to associated tty instance data 322 * Return Value: None 323 */ 324static void hci_uart_tty_wakeup(struct tty_struct *tty) 325{ 326 struct hci_uart *hu = (void *)tty->disc_data; 327 328 BT_DBG(""); 329 330 if (!hu) 331 return; 332 333 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 334 335 if (tty != hu->tty) 336 return; 337 338 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 339 hci_uart_tx_wakeup(hu); 340} 341 342/* hci_uart_tty_receive() 343 * 344 * Called by tty low level driver when receive data is 345 * available. 346 * 347 * Arguments: tty pointer to tty isntance data 348 * data pointer to received data 349 * flags pointer to flags for data 350 * count count of received data in bytes 351 * 352 * Return Value: None 353 */ 354static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count) 355{ 356 struct hci_uart *hu = (void *)tty->disc_data; 357 358 if (!hu || tty != hu->tty) 359 return; 360 361 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags)) 362 return; 363 364 spin_lock(&hu->rx_lock); 365 hu->proto->recv(hu, (void *) data, count); 366 hu->hdev->stat.byte_rx += count; 367 spin_unlock(&hu->rx_lock); 368 369 tty_unthrottle(tty); 370} 371 372static int hci_uart_register_dev(struct hci_uart *hu) 373{ 374 struct hci_dev *hdev; 375 376 BT_DBG(""); 377 378 /* Initialize and register HCI device */ 379 hdev = hci_alloc_dev(); 380 if (!hdev) { 381 BT_ERR("Can't allocate HCI device"); 382 return -ENOMEM; 383 } 384 385 hu->hdev = hdev; 386 387 hdev->bus = HCI_UART; 388 hdev->driver_data = hu; 389 390 hdev->open = hci_uart_open; 391 hdev->close = hci_uart_close; 392 hdev->flush = hci_uart_flush; 393 hdev->send = hci_uart_send_frame; 394 hdev->destruct = hci_uart_destruct; 395 396 hdev->owner = THIS_MODULE; 397 398 if (!reset) 399 set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks); 400 401 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags)) 402 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks); 403 404 if (hci_register_dev(hdev) < 0) { 405 BT_ERR("Can't register HCI device"); 406 hci_free_dev(hdev); 407 return -ENODEV; 408 } 409 410 return 0; 411} 412 413static int hci_uart_set_proto(struct hci_uart *hu, int id) 414{ 415 struct hci_uart_proto *p; 416 int err; 417 418 p = hci_uart_get_proto(id); 419 if (!p) 420 return -EPROTONOSUPPORT; 421 422 err = p->open(hu); 423 if (err) 424 return err; 425 426 hu->proto = p; 427 428 err = hci_uart_register_dev(hu); 429 if (err) { 430 p->close(hu); 431 return err; 432 } 433 434 return 0; 435} 436 437/* hci_uart_tty_ioctl() 438 * 439 * Process IOCTL system call for the tty device. 440 * 441 * Arguments: 442 * 443 * tty pointer to tty instance data 444 * file pointer to open file object for device 445 * cmd IOCTL command code 446 * arg argument for IOCTL call (cmd dependent) 447 * 448 * Return Value: Command dependent 449 */ 450static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file, 451 unsigned int cmd, unsigned long arg) 452{ 453 struct hci_uart *hu = (void *)tty->disc_data; 454 int err = 0; 455 456 BT_DBG(""); 457 458 /* Verify the status of the device */ 459 if (!hu) 460 return -EBADF; 461 462 switch (cmd) { 463 case HCIUARTSETPROTO: 464 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) { 465 err = hci_uart_set_proto(hu, arg); 466 if (err) { 467 clear_bit(HCI_UART_PROTO_SET, &hu->flags); 468 return err; 469 } 470 } else 471 return -EBUSY; 472 break; 473 474 case HCIUARTGETPROTO: 475 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 476 return hu->proto->id; 477 return -EUNATCH; 478 479 case HCIUARTGETDEVICE: 480 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 481 return hu->hdev->id; 482 return -EUNATCH; 483 484 case HCIUARTSETFLAGS: 485 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 486 return -EBUSY; 487 hu->hdev_flags = arg; 488 break; 489 490 case HCIUARTGETFLAGS: 491 return hu->hdev_flags; 492 493 default: 494 err = n_tty_ioctl_helper(tty, file, cmd, arg); 495 break; 496 }; 497 498 return err; 499} 500 501/* 502 * We don't provide read/write/poll interface for user space. 503 */ 504static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file, 505 unsigned char __user *buf, size_t nr) 506{ 507 return 0; 508} 509 510static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file, 511 const unsigned char *data, size_t count) 512{ 513 return 0; 514} 515 516static unsigned int hci_uart_tty_poll(struct tty_struct *tty, 517 struct file *filp, poll_table *wait) 518{ 519 return 0; 520} 521 522static int __init hci_uart_init(void) 523{ 524 static struct tty_ldisc_ops hci_uart_ldisc; 525 int err; 526 527 BT_INFO("HCI UART driver ver %s", VERSION); 528 529 /* Register the tty discipline */ 530 531 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc)); 532 hci_uart_ldisc.magic = TTY_LDISC_MAGIC; 533 hci_uart_ldisc.name = "n_hci"; 534 hci_uart_ldisc.open = hci_uart_tty_open; 535 hci_uart_ldisc.close = hci_uart_tty_close; 536 hci_uart_ldisc.read = hci_uart_tty_read; 537 hci_uart_ldisc.write = hci_uart_tty_write; 538 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl; 539 hci_uart_ldisc.poll = hci_uart_tty_poll; 540 hci_uart_ldisc.receive_buf = hci_uart_tty_receive; 541 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup; 542 hci_uart_ldisc.owner = THIS_MODULE; 543 544 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) { 545 BT_ERR("HCI line discipline registration failed. (%d)", err); 546 return err; 547 } 548 549#ifdef CONFIG_BT_HCIUART_H4 550 h4_init(); 551#endif 552#ifdef CONFIG_BT_HCIUART_BCSP 553 bcsp_init(); 554#endif 555#ifdef CONFIG_BT_HCIUART_LL 556 ll_init(); 557#endif 558#ifdef CONFIG_BT_HCIUART_ATH3K 559 ath_init(); 560#endif 561 562 return 0; 563} 564 565static void __exit hci_uart_exit(void) 566{ 567 int err; 568 569#ifdef CONFIG_BT_HCIUART_H4 570 h4_deinit(); 571#endif 572#ifdef CONFIG_BT_HCIUART_BCSP 573 bcsp_deinit(); 574#endif 575#ifdef CONFIG_BT_HCIUART_LL 576 ll_deinit(); 577#endif 578#ifdef CONFIG_BT_HCIUART_ATH3K 579 ath_deinit(); 580#endif 581 582 /* Release tty registration of line discipline */ 583 if ((err = tty_unregister_ldisc(N_HCI))) 584 BT_ERR("Can't unregister HCI line discipline (%d)", err); 585} 586 587module_init(hci_uart_init); 588module_exit(hci_uart_exit); 589 590module_param(reset, bool, 0644); 591MODULE_PARM_DESC(reset, "Send HCI reset command on initialization"); 592 593MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 594MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION); 595MODULE_VERSION(VERSION); 596MODULE_LICENSE("GPL"); 597MODULE_ALIAS_LDISC(N_HCI); 598