drivers/bluetooth/hci_ldisc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *
   4  *  Bluetooth HCI UART driver
   5  *
   6  *  Copyright (C) 2000-2001  Qualcomm Incorporated
   7  *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
   8  *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
   9  */
  10
  11 #include <linux/module.h>
  12
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/types.h>
  16 #include <linux/fcntl.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/poll.h>
  20
  21 #include <linux/slab.h>
  22 #include <linux/tty.h>
  23 #include <linux/errno.h>
  24 #include <linux/string.h>
  25 #include <linux/signal.h>
  26 #include <linux/ioctl.h>
  27 #include <linux/skbuff.h>
  28 #include <linux/firmware.h>
  29 #include <linux/serdev.h>
  30
  31 #include <net/bluetooth/bluetooth.h>
  32 #include <net/bluetooth/hci_core.h>
  33
  34 #include "btintel.h"
  35 #include "btbcm.h"
  36 #include "hci_uart.h"
  37
  38 #define VERSION "2.3"
  39
  40 static const struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
  41
  42 int hci_uart_register_proto(const struct hci_uart_proto *p)
  43 {
  44         if (p->id >= HCI_UART_MAX_PROTO)
  45                 return -EINVAL;
  46
  47         if (hup[p->id])
  48                 return -EEXIST;
  49
  50         hup[p->id] = p;
  51
  52         BT_INFO("HCI UART protocol %s registered", p->name);
  53
  54         return 0;
  55 }
  56
  57 int hci_uart_unregister_proto(const struct hci_uart_proto *p)
  58 {
  59         if (p->id >= HCI_UART_MAX_PROTO)
  60                 return -EINVAL;
  61
  62         if (!hup[p->id])
  63                 return -EINVAL;
  64
  65         hup[p->id] = NULL;
  66
  67         return 0;
  68 }
  69
  70 static const struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
  71 {
  72         if (id >= HCI_UART_MAX_PROTO)
  73                 return NULL;
  74
  75         return hup[id];
  76 }
  77
  78 static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
  79 {
  80         struct hci_dev *hdev = hu->hdev;
  81
  82         /* Update HCI stat counters */
  83         switch (pkt_type) {
  84         case HCI_COMMAND_PKT:
  85                 hdev->stat.cmd_tx++;
  86                 break;
  87
  88         case HCI_ACLDATA_PKT:
  89                 hdev->stat.acl_tx++;
  90                 break;
  91
  92         case HCI_SCODATA_PKT:
  93                 hdev->stat.sco_tx++;
  94                 break;
  95         }
  96 }
  97
  98 static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
  99 {
 100         struct sk_buff *skb = hu->tx_skb;
 101
 102         if (!skb) {
 103                 percpu_down_read(&hu->proto_lock);
 104
 105                 if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
 106                         skb = hu->proto->dequeue(hu);
 107
 108                 percpu_up_read(&hu->proto_lock);
 109         } else {
 110                 hu->tx_skb = NULL;
 111         }
 112
 113         return skb;
 114 }
 115
 116 int hci_uart_tx_wakeup(struct hci_uart *hu)
 117 {
 118         /* This may be called in an IRQ context, so we can't sleep. Therefore
 119          * we try to acquire the lock only, and if that fails we assume the
 120          * tty is being closed because that is the only time the write lock is
 121          * acquired. If, however, at some point in the future the write lock
 122          * is also acquired in other situations, then this must be revisited.
 123          */
 124         if (!percpu_down_read_trylock(&hu->proto_lock))
 125                 return 0;
 126
 127         if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
 128                 goto no_schedule;
 129
 130         if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
 131                 set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
 132                 goto no_schedule;
 133         }
 134
 135         BT_DBG("");
 136
 137         schedule_work(&hu->write_work);
 138
 139 no_schedule:
 140         percpu_up_read(&hu->proto_lock);
 141
 142         return 0;
 143 }
 144 EXPORT_SYMBOL_GPL(hci_uart_tx_wakeup);
 145
 146 static void hci_uart_write_work(struct work_struct *work)
 147 {
 148         struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
 149         struct tty_struct *tty = hu->tty;
 150         struct hci_dev *hdev = hu->hdev;
 151         struct sk_buff *skb;
 152
 153         /* REVISIT: should we cope with bad skbs or ->write() returning
 154          * and error value ?
 155          */
 156
 157 restart:
 158         clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
 159
 160         while ((skb = hci_uart_dequeue(hu))) {
 161                 int len;
 162
 163                 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 164                 len = tty->ops->write(tty, skb->data, skb->len);
 165                 hdev->stat.byte_tx += len;
 166
 167                 skb_pull(skb, len);
 168                 if (skb->len) {
 169                         hu->tx_skb = skb;
 170                         break;
 171                 }
 172
 173                 hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
 174                 kfree_skb(skb);
 175         }
 176
 177         if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
 178                 goto restart;
 179
 180         clear_bit(HCI_UART_SENDING, &hu->tx_state);
 181         wake_up_bit(&hu->tx_state, HCI_UART_SENDING);
 182 }
 183
 184 void hci_uart_init_work(struct work_struct *work)
 185 {
 186         struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
 187         int err;
 188         struct hci_dev *hdev;
 189
 190         if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
 191                 return;
 192
 193         err = hci_register_dev(hu->hdev);
 194         if (err < 0) {
 195                 BT_ERR("Can't register HCI device");
 196                 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
 197                 hu->proto->close(hu);
 198                 hdev = hu->hdev;
 199                 hu->hdev = NULL;
 200                 hci_free_dev(hdev);
 201                 return;
 202         }
 203
 204         set_bit(HCI_UART_REGISTERED, &hu->flags);
 205 }
 206
 207 int hci_uart_init_ready(struct hci_uart *hu)
 208 {
 209         if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
 210                 return -EALREADY;
 211
 212         schedule_work(&hu->init_ready);
 213
 214         return 0;
 215 }
 216
 217 int hci_uart_wait_until_sent(struct hci_uart *hu)
 218 {
 219         return wait_on_bit_timeout(&hu->tx_state, HCI_UART_SENDING,
 220                                    TASK_INTERRUPTIBLE,
 221                                    msecs_to_jiffies(2000));
 222 }
 223
 224 /* ------- Interface to HCI layer ------ */
 225 /* Reset device */
 226 static int hci_uart_flush(struct hci_dev *hdev)
 227 {
 228         struct hci_uart *hu  = hci_get_drvdata(hdev);
 229         struct tty_struct *tty = hu->tty;
 230
 231         BT_DBG("hdev %p tty %p", hdev, tty);
 232
 233         if (hu->tx_skb) {
 234                 kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
 235         }
 236
 237         /* Flush any pending characters in the driver and discipline. */
 238         tty_ldisc_flush(tty);
 239         tty_driver_flush_buffer(tty);
 240
 241         percpu_down_read(&hu->proto_lock);
 242
 243         if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
 244                 hu->proto->flush(hu);
 245
 246         percpu_up_read(&hu->proto_lock);
 247
 248         return 0;
 249 }
 250
 251 /* Initialize device */
 252 static int hci_uart_open(struct hci_dev *hdev)
 253 {
 254         BT_DBG("%s %p", hdev->name, hdev);
 255
 256         /* Undo clearing this from hci_uart_close() */
 257         hdev->flush = hci_uart_flush;
 258
 259         return 0;
 260 }
 261
 262 /* Close device */
 263 static int hci_uart_close(struct hci_dev *hdev)
 264 {
 265         BT_DBG("hdev %p", hdev);
 266
 267         hci_uart_flush(hdev);
 268         hdev->flush = NULL;
 269         return 0;
 270 }
 271
 272 /* Send frames from HCI layer */
 273 static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 274 {
 275         struct hci_uart *hu = hci_get_drvdata(hdev);
 276
 277         BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
 278                skb->len);
 279
 280         percpu_down_read(&hu->proto_lock);
 281
 282         if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
 283                 percpu_up_read(&hu->proto_lock);
 284                 return -EUNATCH;
 285         }
 286
 287         hu->proto->enqueue(hu, skb);
 288         percpu_up_read(&hu->proto_lock);
 289
 290         hci_uart_tx_wakeup(hu);
 291
 292         return 0;
 293 }
 294
 295 /* Flow control or un-flow control the device */
 296 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
 297 {
 298         struct tty_struct *tty = hu->tty;
 299         struct ktermios ktermios;
 300         int status;
 301         unsigned int set = 0;
 302         unsigned int clear = 0;
 303
 304         if (hu->serdev) {
 305                 serdev_device_set_flow_control(hu->serdev, !enable);
 306                 serdev_device_set_rts(hu->serdev, !enable);
 307                 return;
 308         }
 309
 310         if (enable) {
 311                 /* Disable hardware flow control */
 312                 ktermios = tty->termios;
 313                 ktermios.c_cflag &= ~CRTSCTS;
 314                 status = tty_set_termios(tty, &ktermios);
 315                 BT_DBG("Disabling hardware flow control: %s",
 316                        status ? "failed" : "success");
 317
 318                 /* Clear RTS to prevent the device from sending */
 319                 /* Most UARTs need OUT2 to enable interrupts */
 320                 status = tty->driver->ops->tiocmget(tty);
 321                 BT_DBG("Current tiocm 0x%x", status);
 322
 323                 set &= ~(TIOCM_OUT2 | TIOCM_RTS);
 324                 clear = ~set;
 325                 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
 326                        TIOCM_OUT2 | TIOCM_LOOP;
 327                 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
 328                          TIOCM_OUT2 | TIOCM_LOOP;
 329                 status = tty->driver->ops->tiocmset(tty, set, clear);
 330                 BT_DBG("Clearing RTS: %s", status ? "failed" : "success");
 331         } else {
 332                 /* Set RTS to allow the device to send again */
 333                 status = tty->driver->ops->tiocmget(tty);
 334                 BT_DBG("Current tiocm 0x%x", status);
 335
 336                 set |= (TIOCM_OUT2 | TIOCM_RTS);
 337                 clear = ~set;
 338                 set &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
 339                        TIOCM_OUT2 | TIOCM_LOOP;
 340                 clear &= TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 |
 341                          TIOCM_OUT2 | TIOCM_LOOP;
 342                 status = tty->driver->ops->tiocmset(tty, set, clear);
 343                 BT_DBG("Setting RTS: %s", status ? "failed" : "success");
 344
 345                 /* Re-enable hardware flow control */
 346                 ktermios = tty->termios;
 347                 ktermios.c_cflag |= CRTSCTS;
 348                 status = tty_set_termios(tty, &ktermios);
 349                 BT_DBG("Enabling hardware flow control: %s",
 350                        status ? "failed" : "success");
 351         }
 352 }
 353
 354 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
 355                          unsigned int oper_speed)
 356 {
 357         hu->init_speed = init_speed;
 358         hu->oper_speed = oper_speed;
 359 }
 360
 361 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
 362 {
 363         struct tty_struct *tty = hu->tty;
 364         struct ktermios ktermios;
 365
 366         ktermios = tty->termios;
 367         ktermios.c_cflag &= ~CBAUD;
 368         tty_termios_encode_baud_rate(&ktermios, speed, speed);
 369
 370         /* tty_set_termios() return not checked as it is always 0 */
 371         tty_set_termios(tty, &ktermios);
 372
 373         BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
 374                tty->termios.c_ispeed, tty->termios.c_ospeed);
 375 }
 376
 377 static int hci_uart_setup(struct hci_dev *hdev)
 378 {
 379         struct hci_uart *hu = hci_get_drvdata(hdev);
 380         struct hci_rp_read_local_version *ver;
 381         struct sk_buff *skb;
 382         unsigned int speed;
 383         int err;
 384
 385         /* Init speed if any */
 386         if (hu->init_speed)
 387                 speed = hu->init_speed;
 388         else if (hu->proto->init_speed)
 389                 speed = hu->proto->init_speed;
 390         else
 391                 speed = 0;
 392
 393         if (speed)
 394                 hci_uart_set_baudrate(hu, speed);
 395
 396         /* Operational speed if any */
 397         if (hu->oper_speed)
 398                 speed = hu->oper_speed;
 399         else if (hu->proto->oper_speed)
 400                 speed = hu->proto->oper_speed;
 401         else
 402                 speed = 0;
 403
 404         if (hu->proto->set_baudrate && speed) {
 405                 err = hu->proto->set_baudrate(hu, speed);
 406                 if (!err)
 407                         hci_uart_set_baudrate(hu, speed);
 408         }
 409
 410         if (hu->proto->setup)
 411                 return hu->proto->setup(hu);
 412
 413         if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
 414                 return 0;
 415
 416         skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
 417                              HCI_INIT_TIMEOUT);
 418         if (IS_ERR(skb)) {
 419                 BT_ERR("%s: Reading local version information failed (%ld)",
 420                        hdev->name, PTR_ERR(skb));
 421                 return 0;
 422         }
 423
 424         if (skb->len != sizeof(*ver)) {
 425                 BT_ERR("%s: Event length mismatch for version information",
 426                        hdev->name);
 427                 goto done;
 428         }
 429
 430         ver = (struct hci_rp_read_local_version *)skb->data;
 431
 432         switch (le16_to_cpu(ver->manufacturer)) {
 433 #ifdef CONFIG_BT_HCIUART_INTEL
 434         case 2:
 435                 hdev->set_bdaddr = btintel_set_bdaddr;
 436                 btintel_check_bdaddr(hdev);
 437                 break;
 438 #endif
 439 #ifdef CONFIG_BT_HCIUART_BCM
 440         case 15:
 441                 hdev->set_bdaddr = btbcm_set_bdaddr;
 442                 btbcm_check_bdaddr(hdev);
 443                 break;
 444 #endif
 445         default:
 446                 break;
 447         }
 448
 449 done:
 450         kfree_skb(skb);
 451         return 0;
 452 }
 453
 454 /* ------ LDISC part ------ */
 455 /* hci_uart_tty_open
 456  *
 457  *     Called when line discipline changed to HCI_UART.
 458  *
 459  * Arguments:
 460  *     tty    pointer to tty info structure
 461  * Return Value:
 462  *     0 if success, otherwise error code
 463  */
 464 static int hci_uart_tty_open(struct tty_struct *tty)
 465 {
 466         struct hci_uart *hu;
 467
 468         BT_DBG("tty %p", tty);
 469
 470         /* Error if the tty has no write op instead of leaving an exploitable
 471          * hole
 472          */
 473         if (tty->ops->write == NULL)
 474                 return -EOPNOTSUPP;
 475
 476         hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL);
 477         if (!hu) {
 478                 BT_ERR("Can't allocate control structure");
 479                 return -ENFILE;
 480         }
 481
 482         tty->disc_data = hu;
 483         hu->tty = tty;
 484         tty->receive_room = 65536;
 485
 486         /* disable alignment support by default */
 487         hu->alignment = 1;
 488         hu->padding = 0;
 489
 490         INIT_WORK(&hu->init_ready, hci_uart_init_work);
 491         INIT_WORK(&hu->write_work, hci_uart_write_work);
 492
 493         percpu_init_rwsem(&hu->proto_lock);
 494
 495         /* Flush any pending characters in the driver */
 496         tty_driver_flush_buffer(tty);
 497
 498         return 0;
 499 }
 500
 501 /* hci_uart_tty_close()
 502  *
 503  *    Called when the line discipline is changed to something
 504  *    else, the tty is closed, or the tty detects a hangup.
 505  */
 506 static void hci_uart_tty_close(struct tty_struct *tty)
 507 {
 508         struct hci_uart *hu = tty->disc_data;
 509         struct hci_dev *hdev;
 510
 511         BT_DBG("tty %p", tty);
 512
 513         /* Detach from the tty */
 514         tty->disc_data = NULL;
 515
 516         if (!hu)
 517                 return;
 518
 519         hdev = hu->hdev;
 520         if (hdev)
 521                 hci_uart_close(hdev);
 522
 523         if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
 524                 percpu_down_write(&hu->proto_lock);
 525                 clear_bit(HCI_UART_PROTO_READY, &hu->flags);
 526                 percpu_up_write(&hu->proto_lock);
 527
 528                 cancel_work_sync(&hu->write_work);
 529
 530                 if (hdev) {
 531                         if (test_bit(HCI_UART_REGISTERED, &hu->flags))
 532                                 hci_unregister_dev(hdev);
 533                         hci_free_dev(hdev);
 534                 }
 535                 hu->proto->close(hu);
 536         }
 537         clear_bit(HCI_UART_PROTO_SET, &hu->flags);
 538
 539         percpu_free_rwsem(&hu->proto_lock);
 540
 541         kfree(hu);
 542 }
 543
 544 /* hci_uart_tty_wakeup()
 545  *
 546  *    Callback for transmit wakeup. Called when low level
 547  *    device driver can accept more send data.
 548  *
 549  * Arguments:        tty    pointer to associated tty instance data
 550  * Return Value:    None
 551  */
 552 static void hci_uart_tty_wakeup(struct tty_struct *tty)
 553 {
 554         struct hci_uart *hu = tty->disc_data;
 555
 556         BT_DBG("");
 557
 558         if (!hu)
 559                 return;
 560
 561         clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 562
 563         if (tty != hu->tty)
 564                 return;
 565
 566         if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
 567                 hci_uart_tx_wakeup(hu);
 568 }
 569
 570 /* hci_uart_tty_receive()
 571  *
 572  *     Called by tty low level driver when receive data is
 573  *     available.
 574  *
 575  * Arguments:  tty          pointer to tty isntance data
 576  *             data         pointer to received data
 577  *             flags        pointer to flags for data
 578  *             count        count of received data in bytes
 579  *
 580  * Return Value:    None
 581  */
 582 static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
 583                                  char *flags, int count)
 584 {
 585         struct hci_uart *hu = tty->disc_data;
 586
 587         if (!hu || tty != hu->tty)
 588                 return;
 589
 590         percpu_down_read(&hu->proto_lock);
 591
 592         if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
 593                 percpu_up_read(&hu->proto_lock);
 594                 return;
 595         }
 596
 597         /* It does not need a lock here as it is already protected by a mutex in
 598          * tty caller
 599          */
 600         hu->proto->recv(hu, data, count);
 601         percpu_up_read(&hu->proto_lock);
 602
 603         if (hu->hdev)
 604                 hu->hdev->stat.byte_rx += count;
 605
 606         tty_unthrottle(tty);
 607 }
 608
 609 static int hci_uart_register_dev(struct hci_uart *hu)
 610 {
 611         struct hci_dev *hdev;
 612         int err;
 613
 614         BT_DBG("");
 615
 616         /* Initialize and register HCI device */
 617         hdev = hci_alloc_dev();
 618         if (!hdev) {
 619                 BT_ERR("Can't allocate HCI device");
 620                 return -ENOMEM;
 621         }
 622
 623         hu->hdev = hdev;
 624
 625         hdev->bus = HCI_UART;
 626         hci_set_drvdata(hdev, hu);
 627
 628         /* Only when vendor specific setup callback is provided, consider
 629          * the manufacturer information valid. This avoids filling in the
 630          * value for Ericsson when nothing is specified.
 631          */
 632         if (hu->proto->setup)
 633                 hdev->manufacturer = hu->proto->manufacturer;
 634
 635         hdev->open  = hci_uart_open;
 636         hdev->close = hci_uart_close;
 637         hdev->flush = hci_uart_flush;
 638         hdev->send  = hci_uart_send_frame;
 639         hdev->setup = hci_uart_setup;
 640         SET_HCIDEV_DEV(hdev, hu->tty->dev);
 641
 642         if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
 643                 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
 644
 645         if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
 646                 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
 647
 648         if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
 649                 set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
 650
 651         if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
 652                 hdev->dev_type = HCI_AMP;
 653         else
 654                 hdev->dev_type = HCI_PRIMARY;
 655
 656         /* Only call open() for the protocol after hdev is fully initialized as
 657          * open() (or a timer/workqueue it starts) may attempt to reference it.
 658          */
 659         err = hu->proto->open(hu);
 660         if (err) {
 661                 hu->hdev = NULL;
 662                 hci_free_dev(hdev);
 663                 return err;
 664         }
 665
 666         if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
 667                 return 0;
 668
 669         if (hci_register_dev(hdev) < 0) {
 670                 BT_ERR("Can't register HCI device");
 671                 hu->proto->close(hu);
 672                 hu->hdev = NULL;
 673                 hci_free_dev(hdev);
 674                 return -ENODEV;
 675         }
 676
 677         set_bit(HCI_UART_REGISTERED, &hu->flags);
 678
 679         return 0;
 680 }
 681
 682 static int hci_uart_set_proto(struct hci_uart *hu, int id)
 683 {
 684         const struct hci_uart_proto *p;
 685         int err;
 686
 687         p = hci_uart_get_proto(id);
 688         if (!p)
 689                 return -EPROTONOSUPPORT;
 690
 691         hu->proto = p;
 692
 693         err = hci_uart_register_dev(hu);
 694         if (err) {
 695                 return err;
 696         }
 697
 698         set_bit(HCI_UART_PROTO_READY, &hu->flags);
 699         return 0;
 700 }
 701
 702 static int hci_uart_set_flags(struct hci_uart *hu, unsigned long flags)
 703 {
 704         unsigned long valid_flags = BIT(HCI_UART_RAW_DEVICE) |
 705                                     BIT(HCI_UART_RESET_ON_INIT) |
 706                                     BIT(HCI_UART_CREATE_AMP) |
 707                                     BIT(HCI_UART_INIT_PENDING) |
 708                                     BIT(HCI_UART_EXT_CONFIG) |
 709                                     BIT(HCI_UART_VND_DETECT);
 710
 711         if (flags & ~valid_flags)
 712                 return -EINVAL;
 713
 714         hu->hdev_flags = flags;
 715
 716         return 0;
 717 }
 718
 719 /* hci_uart_tty_ioctl()
 720  *
 721  *    Process IOCTL system call for the tty device.
 722  *
 723  * Arguments:
 724  *
 725  *    tty        pointer to tty instance data
 726  *    file       pointer to open file object for device
 727  *    cmd        IOCTL command code
 728  *    arg        argument for IOCTL call (cmd dependent)
 729  *
 730  * Return Value:    Command dependent
 731  */
 732 static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
 733                               unsigned int cmd, unsigned long arg)
 734 {
 735         struct hci_uart *hu = tty->disc_data;
 736         int err = 0;
 737
 738         BT_DBG("");
 739
 740         /* Verify the status of the device */
 741         if (!hu)
 742                 return -EBADF;
 743
 744         switch (cmd) {
 745         case HCIUARTSETPROTO:
 746                 if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
 747                         err = hci_uart_set_proto(hu, arg);
 748                         if (err)
 749                                 clear_bit(HCI_UART_PROTO_SET, &hu->flags);
 750                 } else
 751                         err = -EBUSY;
 752                 break;
 753
 754         case HCIUARTGETPROTO:
 755                 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
 756                         err = hu->proto->id;
 757                 else
 758                         err = -EUNATCH;
 759                 break;
 760
 761         case HCIUARTGETDEVICE:
 762                 if (test_bit(HCI_UART_REGISTERED, &hu->flags))
 763                         err = hu->hdev->id;
 764                 else
 765                         err = -EUNATCH;
 766                 break;
 767
 768         case HCIUARTSETFLAGS:
 769                 if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
 770                         err = -EBUSY;
 771                 else
 772                         err = hci_uart_set_flags(hu, arg);
 773                 break;
 774
 775         case HCIUARTGETFLAGS:
 776                 err = hu->hdev_flags;
 777                 break;
 778
 779         default:
 780                 err = n_tty_ioctl_helper(tty, file, cmd, arg);
 781                 break;
 782         }
 783
 784         return err;
 785 }
 786
 787 /*
 788  * We don't provide read/write/poll interface for user space.
 789  */
 790 static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
 791                                  unsigned char __user *buf, size_t nr)
 792 {
 793         return 0;
 794 }
 795
 796 static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
 797                                   const unsigned char *data, size_t count)
 798 {
 799         return 0;
 800 }
 801
 802 static __poll_t hci_uart_tty_poll(struct tty_struct *tty,
 803                                       struct file *filp, poll_table *wait)
 804 {
 805         return 0;
 806 }
 807
 808 static int __init hci_uart_init(void)
 809 {
 810         static struct tty_ldisc_ops hci_uart_ldisc;
 811         int err;
 812
 813         BT_INFO("HCI UART driver ver %s", VERSION);
 814
 815         /* Register the tty discipline */
 816
 817         memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
 818         hci_uart_ldisc.magic            = TTY_LDISC_MAGIC;
 819         hci_uart_ldisc.name             = "n_hci";
 820         hci_uart_ldisc.open             = hci_uart_tty_open;
 821         hci_uart_ldisc.close            = hci_uart_tty_close;
 822         hci_uart_ldisc.read             = hci_uart_tty_read;
 823         hci_uart_ldisc.write            = hci_uart_tty_write;
 824         hci_uart_ldisc.ioctl            = hci_uart_tty_ioctl;
 825         hci_uart_ldisc.compat_ioctl     = hci_uart_tty_ioctl;
 826         hci_uart_ldisc.poll             = hci_uart_tty_poll;
 827         hci_uart_ldisc.receive_buf      = hci_uart_tty_receive;
 828         hci_uart_ldisc.write_wakeup     = hci_uart_tty_wakeup;
 829         hci_uart_ldisc.owner            = THIS_MODULE;
 830
 831         err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
 832         if (err) {
 833                 BT_ERR("HCI line discipline registration failed. (%d)", err);
 834                 return err;
 835         }
 836
 837 #ifdef CONFIG_BT_HCIUART_H4
 838         h4_init();
 839 #endif
 840 #ifdef CONFIG_BT_HCIUART_BCSP
 841         bcsp_init();
 842 #endif
 843 #ifdef CONFIG_BT_HCIUART_LL
 844         ll_init();
 845 #endif
 846 #ifdef CONFIG_BT_HCIUART_ATH3K
 847         ath_init();
 848 #endif
 849 #ifdef CONFIG_BT_HCIUART_3WIRE
 850         h5_init();
 851 #endif
 852 #ifdef CONFIG_BT_HCIUART_INTEL
 853         intel_init();
 854 #endif
 855 #ifdef CONFIG_BT_HCIUART_BCM
 856         bcm_init();
 857 #endif
 858 #ifdef CONFIG_BT_HCIUART_QCA
 859         qca_init();
 860 #endif
 861 #ifdef CONFIG_BT_HCIUART_AG6XX
 862         ag6xx_init();
 863 #endif
 864 #ifdef CONFIG_BT_HCIUART_MRVL
 865         mrvl_init();
 866 #endif
 867
 868         return 0;
 869 }
 870
 871 static void __exit hci_uart_exit(void)
 872 {
 873         int err;
 874
 875 #ifdef CONFIG_BT_HCIUART_H4
 876         h4_deinit();
 877 #endif
 878 #ifdef CONFIG_BT_HCIUART_BCSP
 879         bcsp_deinit();
 880 #endif
 881 #ifdef CONFIG_BT_HCIUART_LL
 882         ll_deinit();
 883 #endif
 884 #ifdef CONFIG_BT_HCIUART_ATH3K
 885         ath_deinit();
 886 #endif
 887 #ifdef CONFIG_BT_HCIUART_3WIRE
 888         h5_deinit();
 889 #endif
 890 #ifdef CONFIG_BT_HCIUART_INTEL
 891         intel_deinit();
 892 #endif
 893 #ifdef CONFIG_BT_HCIUART_BCM
 894         bcm_deinit();
 895 #endif
 896 #ifdef CONFIG_BT_HCIUART_QCA
 897         qca_deinit();
 898 #endif
 899 #ifdef CONFIG_BT_HCIUART_AG6XX
 900         ag6xx_deinit();
 901 #endif
 902 #ifdef CONFIG_BT_HCIUART_MRVL
 903         mrvl_deinit();
 904 #endif
 905
 906         /* Release tty registration of line discipline */
 907         err = tty_unregister_ldisc(N_HCI);
 908         if (err)
 909                 BT_ERR("Can't unregister HCI line discipline (%d)", err);
 910 }
 911
 912 module_init(hci_uart_init);
 913 module_exit(hci_uart_exit);
 914
 915 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
 916 MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
 917 MODULE_VERSION(VERSION);
 918 MODULE_LICENSE("GPL");
 919 MODULE_ALIAS_LDISC(N_HCI);