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 51 static int reset = 0; 52 53 static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO]; 54 55 int 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 68 int 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 81 static 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 89 static 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 } 108 109 static 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 } 120 121 int 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(""); 133 134 restart: 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 */ 163 static 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 */ 175 static 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 */ 197 static 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 */ 210 static 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 } 233 234 static 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 */ 253 static 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 if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) { 263 BT_ERR("Can't allocate control structure"); 264 return -ENFILE; 265 } 266 267 tty->disc_data = hu; 268 hu->tty = tty; 269 tty->receive_room = 65536; 270 271 spin_lock_init(&hu->rx_lock); 272 273 /* Flush any pending characters in the driver and line discipline. */ 274 275 /* FIXME: why is this needed. Note don't use ldisc_ref here as the 276 open path is before the ldisc is referencable */ 277 278 if (tty->ldisc->ops->flush_buffer) 279 tty->ldisc->ops->flush_buffer(tty); 280 tty_driver_flush_buffer(tty); 281 282 return 0; 283 } 284 285 /* hci_uart_tty_close() 286 * 287 * Called when the line discipline is changed to something 288 * else, the tty is closed, or the tty detects a hangup. 289 */ 290 static void hci_uart_tty_close(struct tty_struct *tty) 291 { 292 struct hci_uart *hu = (void *)tty->disc_data; 293 294 BT_DBG("tty %p", tty); 295 296 /* Detach from the tty */ 297 tty->disc_data = NULL; 298 299 if (hu) { 300 struct hci_dev *hdev = hu->hdev; 301 302 if (hdev) 303 hci_uart_close(hdev); 304 305 if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) { 306 hu->proto->close(hu); 307 hci_unregister_dev(hdev); 308 hci_free_dev(hdev); 309 } 310 } 311 } 312 313 /* hci_uart_tty_wakeup() 314 * 315 * Callback for transmit wakeup. Called when low level 316 * device driver can accept more send data. 317 * 318 * Arguments: tty pointer to associated tty instance data 319 * Return Value: None 320 */ 321 static void hci_uart_tty_wakeup(struct tty_struct *tty) 322 { 323 struct hci_uart *hu = (void *)tty->disc_data; 324 325 BT_DBG(""); 326 327 if (!hu) 328 return; 329 330 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 331 332 if (tty != hu->tty) 333 return; 334 335 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 336 hci_uart_tx_wakeup(hu); 337 } 338 339 /* hci_uart_tty_receive() 340 * 341 * Called by tty low level driver when receive data is 342 * available. 343 * 344 * Arguments: tty pointer to tty isntance data 345 * data pointer to received data 346 * flags pointer to flags for data 347 * count count of received data in bytes 348 * 349 * Return Value: None 350 */ 351 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count) 352 { 353 struct hci_uart *hu = (void *)tty->disc_data; 354 355 if (!hu || tty != hu->tty) 356 return; 357 358 if (!test_bit(HCI_UART_PROTO_SET, &hu->flags)) 359 return; 360 361 spin_lock(&hu->rx_lock); 362 hu->proto->recv(hu, (void *) data, count); 363 hu->hdev->stat.byte_rx += count; 364 spin_unlock(&hu->rx_lock); 365 366 tty_unthrottle(tty); 367 } 368 369 static int hci_uart_register_dev(struct hci_uart *hu) 370 { 371 struct hci_dev *hdev; 372 373 BT_DBG(""); 374 375 /* Initialize and register HCI device */ 376 hdev = hci_alloc_dev(); 377 if (!hdev) { 378 BT_ERR("Can't allocate HCI device"); 379 return -ENOMEM; 380 } 381 382 hu->hdev = hdev; 383 384 hdev->bus = HCI_UART; 385 hdev->driver_data = hu; 386 387 hdev->open = hci_uart_open; 388 hdev->close = hci_uart_close; 389 hdev->flush = hci_uart_flush; 390 hdev->send = hci_uart_send_frame; 391 hdev->destruct = hci_uart_destruct; 392 393 hdev->owner = THIS_MODULE; 394 395 if (!reset) 396 set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks); 397 398 if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags)) 399 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks); 400 401 if (hci_register_dev(hdev) < 0) { 402 BT_ERR("Can't register HCI device"); 403 hci_free_dev(hdev); 404 return -ENODEV; 405 } 406 407 return 0; 408 } 409 410 static int hci_uart_set_proto(struct hci_uart *hu, int id) 411 { 412 struct hci_uart_proto *p; 413 int err; 414 415 p = hci_uart_get_proto(id); 416 if (!p) 417 return -EPROTONOSUPPORT; 418 419 err = p->open(hu); 420 if (err) 421 return err; 422 423 hu->proto = p; 424 425 err = hci_uart_register_dev(hu); 426 if (err) { 427 p->close(hu); 428 return err; 429 } 430 431 return 0; 432 } 433 434 /* hci_uart_tty_ioctl() 435 * 436 * Process IOCTL system call for the tty device. 437 * 438 * Arguments: 439 * 440 * tty pointer to tty instance data 441 * file pointer to open file object for device 442 * cmd IOCTL command code 443 * arg argument for IOCTL call (cmd dependent) 444 * 445 * Return Value: Command dependent 446 */ 447 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file, 448 unsigned int cmd, unsigned long arg) 449 { 450 struct hci_uart *hu = (void *)tty->disc_data; 451 int err = 0; 452 453 BT_DBG(""); 454 455 /* Verify the status of the device */ 456 if (!hu) 457 return -EBADF; 458 459 switch (cmd) { 460 case HCIUARTSETPROTO: 461 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) { 462 err = hci_uart_set_proto(hu, arg); 463 if (err) { 464 clear_bit(HCI_UART_PROTO_SET, &hu->flags); 465 return err; 466 } 467 } else 468 return -EBUSY; 469 break; 470 471 case HCIUARTGETPROTO: 472 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 473 return hu->proto->id; 474 return -EUNATCH; 475 476 case HCIUARTGETDEVICE: 477 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 478 return hu->hdev->id; 479 return -EUNATCH; 480 481 case HCIUARTSETFLAGS: 482 if (test_bit(HCI_UART_PROTO_SET, &hu->flags)) 483 return -EBUSY; 484 hu->hdev_flags = arg; 485 break; 486 487 case HCIUARTGETFLAGS: 488 return hu->hdev_flags; 489 490 default: 491 err = n_tty_ioctl_helper(tty, file, cmd, arg); 492 break; 493 }; 494 495 return err; 496 } 497 498 /* 499 * We don't provide read/write/poll interface for user space. 500 */ 501 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file, 502 unsigned char __user *buf, size_t nr) 503 { 504 return 0; 505 } 506 507 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file, 508 const unsigned char *data, size_t count) 509 { 510 return 0; 511 } 512 513 static unsigned int hci_uart_tty_poll(struct tty_struct *tty, 514 struct file *filp, poll_table *wait) 515 { 516 return 0; 517 } 518 519 static int __init hci_uart_init(void) 520 { 521 static struct tty_ldisc_ops hci_uart_ldisc; 522 int err; 523 524 BT_INFO("HCI UART driver ver %s", VERSION); 525 526 /* Register the tty discipline */ 527 528 memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc)); 529 hci_uart_ldisc.magic = TTY_LDISC_MAGIC; 530 hci_uart_ldisc.name = "n_hci"; 531 hci_uart_ldisc.open = hci_uart_tty_open; 532 hci_uart_ldisc.close = hci_uart_tty_close; 533 hci_uart_ldisc.read = hci_uart_tty_read; 534 hci_uart_ldisc.write = hci_uart_tty_write; 535 hci_uart_ldisc.ioctl = hci_uart_tty_ioctl; 536 hci_uart_ldisc.poll = hci_uart_tty_poll; 537 hci_uart_ldisc.receive_buf = hci_uart_tty_receive; 538 hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup; 539 hci_uart_ldisc.owner = THIS_MODULE; 540 541 if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) { 542 BT_ERR("HCI line discipline registration failed. (%d)", err); 543 return err; 544 } 545 546 #ifdef CONFIG_BT_HCIUART_H4 547 h4_init(); 548 #endif 549 #ifdef CONFIG_BT_HCIUART_BCSP 550 bcsp_init(); 551 #endif 552 #ifdef CONFIG_BT_HCIUART_LL 553 ll_init(); 554 #endif 555 #ifdef CONFIG_BT_HCIUART_ATH3K 556 ath_init(); 557 #endif 558 559 return 0; 560 } 561 562 static void __exit hci_uart_exit(void) 563 { 564 int err; 565 566 #ifdef CONFIG_BT_HCIUART_H4 567 h4_deinit(); 568 #endif 569 #ifdef CONFIG_BT_HCIUART_BCSP 570 bcsp_deinit(); 571 #endif 572 #ifdef CONFIG_BT_HCIUART_LL 573 ll_deinit(); 574 #endif 575 #ifdef CONFIG_BT_HCIUART_ATH3K 576 ath_deinit(); 577 #endif 578 579 /* Release tty registration of line discipline */ 580 if ((err = tty_unregister_ldisc(N_HCI))) 581 BT_ERR("Can't unregister HCI line discipline (%d)", err); 582 } 583 584 module_init(hci_uart_init); 585 module_exit(hci_uart_exit); 586 587 module_param(reset, bool, 0644); 588 MODULE_PARM_DESC(reset, "Send HCI reset command on initialization"); 589 590 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 591 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION); 592 MODULE_VERSION(VERSION); 593 MODULE_LICENSE("GPL"); 594 MODULE_ALIAS_LDISC(N_HCI); 595