drivers/usb/serial/usb-serial.c

   1 /*
   2  * USB Serial Converter driver
   3  *
   4  * Copyright (C) 2009 - 2013 Johan Hovold (jhovold@gmail.com)
   5  * Copyright (C) 1999 - 2012 Greg Kroah-Hartman (greg@kroah.com)
   6  * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
   7  * Copyright (C) 2000 Al Borchers (borchers@steinerpoint.com)
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License version
  11  *      2 as published by the Free Software Foundation.
  12  *
  13  * This driver was originally based on the ACM driver by Armin Fuerst (which was
  14  * based on a driver by Brad Keryan)
  15  *
  16  * See Documentation/usb/usb-serial.txt for more information on using this
  17  * driver
  18  */
  19
  20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 #include <linux/kernel.h>
  23 #include <linux/errno.h>
  24 #include <linux/init.h>
  25 #include <linux/slab.h>
  26 #include <linux/tty.h>
  27 #include <linux/tty_driver.h>
  28 #include <linux/tty_flip.h>
  29 #include <linux/module.h>
  30 #include <linux/moduleparam.h>
  31 #include <linux/seq_file.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/mutex.h>
  34 #include <linux/list.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/serial.h>
  37 #include <linux/usb.h>
  38 #include <linux/usb/serial.h>
  39 #include <linux/kfifo.h>
  40 #include "pl2303.h"
  41
  42 #define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
  43 #define DRIVER_DESC "USB Serial Driver core"
  44
  45 /* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
  46    the MODULE_DEVICE_TABLE declarations in each serial driver
  47    cause the "hotplug" program to pull in whatever module is necessary
  48    via modprobe, and modprobe will load usbserial because the serial
  49    drivers depend on it.
  50 */
  51
  52 static struct usb_serial *serial_table[SERIAL_TTY_MINORS];
  53 static DEFINE_MUTEX(table_lock);
  54 static LIST_HEAD(usb_serial_driver_list);
  55
  56 /*
  57  * Look up the serial structure.  If it is found and it hasn't been
  58  * disconnected, return with its disc_mutex held and its refcount
  59  * incremented.  Otherwise return NULL.
  60  */
  61 struct usb_serial *usb_serial_get_by_index(unsigned index)
  62 {
  63         struct usb_serial *serial;
  64
  65         mutex_lock(&table_lock);
  66         serial = serial_table[index];
  67
  68         if (serial) {
  69                 mutex_lock(&serial->disc_mutex);
  70                 if (serial->disconnected) {
  71                         mutex_unlock(&serial->disc_mutex);
  72                         serial = NULL;
  73                 } else {
  74                         kref_get(&serial->kref);
  75                 }
  76         }
  77         mutex_unlock(&table_lock);
  78         return serial;
  79 }
  80
  81 static struct usb_serial *get_free_serial(struct usb_serial *serial,
  82                                         int num_ports, unsigned int *minor)
  83 {
  84         unsigned int i, j;
  85         int good_spot;
  86
  87         dev_dbg(&serial->interface->dev, "%s %d\n", __func__, num_ports);
  88
  89         *minor = 0;
  90         mutex_lock(&table_lock);
  91         for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
  92                 if (serial_table[i])
  93                         continue;
  94
  95                 good_spot = 1;
  96                 for (j = 1; j <= num_ports-1; ++j)
  97                         if ((i+j >= SERIAL_TTY_MINORS) || (serial_table[i+j])) {
  98                                 good_spot = 0;
  99                                 i += j;
 100                                 break;
 101                         }
 102                 if (good_spot == 0)
 103                         continue;
 104
 105                 *minor = i;
 106                 j = 0;
 107                 dev_dbg(&serial->interface->dev, "%s - minor base = %d\n", __func__, *minor);
 108                 for (i = *minor; (i < (*minor + num_ports)) && (i < SERIAL_TTY_MINORS); ++i) {
 109                         serial_table[i] = serial;
 110                         serial->port[j++]->number = i;
 111                 }
 112                 mutex_unlock(&table_lock);
 113                 return serial;
 114         }
 115         mutex_unlock(&table_lock);
 116         return NULL;
 117 }
 118
 119 static void return_serial(struct usb_serial *serial)
 120 {
 121         int i;
 122
 123         mutex_lock(&table_lock);
 124         for (i = 0; i < serial->num_ports; ++i)
 125                 serial_table[serial->minor + i] = NULL;
 126         mutex_unlock(&table_lock);
 127 }
 128
 129 static void destroy_serial(struct kref *kref)
 130 {
 131         struct usb_serial *serial;
 132         struct usb_serial_port *port;
 133         int i;
 134
 135         serial = to_usb_serial(kref);
 136
 137         /* return the minor range that this device had */
 138         if (serial->minor != SERIAL_TTY_NO_MINOR)
 139                 return_serial(serial);
 140
 141         if (serial->attached && serial->type->release)
 142                 serial->type->release(serial);
 143
 144         /* Now that nothing is using the ports, they can be freed */
 145         for (i = 0; i < serial->num_port_pointers; ++i) {
 146                 port = serial->port[i];
 147                 if (port) {
 148                         port->serial = NULL;
 149                         put_device(&port->dev);
 150                 }
 151         }
 152
 153         usb_put_intf(serial->interface);
 154         usb_put_dev(serial->dev);
 155         kfree(serial);
 156 }
 157
 158 void usb_serial_put(struct usb_serial *serial)
 159 {
 160         kref_put(&serial->kref, destroy_serial);
 161 }
 162
 163 /*****************************************************************************
 164  * Driver tty interface functions
 165  *****************************************************************************/
 166
 167 /**
 168  * serial_install - install tty
 169  * @driver: the driver (USB in our case)
 170  * @tty: the tty being created
 171  *
 172  * Create the termios objects for this tty.  We use the default
 173  * USB serial settings but permit them to be overridden by
 174  * serial->type->init_termios.
 175  *
 176  * This is the first place a new tty gets used.  Hence this is where we
 177  * acquire references to the usb_serial structure and the driver module,
 178  * where we store a pointer to the port, and where we do an autoresume.
 179  * All these actions are reversed in serial_cleanup().
 180  */
 181 static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 182 {
 183         int idx = tty->index;
 184         struct usb_serial *serial;
 185         struct usb_serial_port *port;
 186         int retval = -ENODEV;
 187
 188         serial = usb_serial_get_by_index(idx);
 189         if (!serial)
 190                 return retval;
 191
 192         port = serial->port[idx - serial->minor];
 193         if (!port)
 194                 goto error_no_port;
 195         if (!try_module_get(serial->type->driver.owner))
 196                 goto error_module_get;
 197
 198         retval = usb_autopm_get_interface(serial->interface);
 199         if (retval)
 200                 goto error_get_interface;
 201
 202         retval = tty_port_install(&port->port, driver, tty);
 203         if (retval)
 204                 goto error_init_termios;
 205
 206         mutex_unlock(&serial->disc_mutex);
 207
 208         /* allow the driver to update the settings */
 209         if (serial->type->init_termios)
 210                 serial->type->init_termios(tty);
 211
 212         tty->driver_data = port;
 213
 214         return retval;
 215
 216  error_init_termios:
 217         usb_autopm_put_interface(serial->interface);
 218  error_get_interface:
 219         module_put(serial->type->driver.owner);
 220  error_module_get:
 221  error_no_port:
 222         usb_serial_put(serial);
 223         mutex_unlock(&serial->disc_mutex);
 224         return retval;
 225 }
 226
 227 static int serial_port_activate(struct tty_port *tport, struct tty_struct *tty)
 228 {
 229         struct usb_serial_port *port =
 230                 container_of(tport, struct usb_serial_port, port);
 231         struct usb_serial *serial = port->serial;
 232         int retval;
 233
 234         mutex_lock(&serial->disc_mutex);
 235         if (serial->disconnected)
 236                 retval = -ENODEV;
 237         else
 238                 retval = port->serial->type->open(tty, port);
 239         mutex_unlock(&serial->disc_mutex);
 240
 241         if (retval < 0)
 242                 retval = usb_translate_errors(retval);
 243
 244         return retval;
 245 }
 246
 247 static int serial_open(struct tty_struct *tty, struct file *filp)
 248 {
 249         struct usb_serial_port *port = tty->driver_data;
 250
 251         dev_dbg(tty->dev, "%s\n", __func__);
 252
 253         return tty_port_open(&port->port, tty, filp);
 254 }
 255
 256 /**
 257  * serial_port_shutdown - shut down hardware
 258  * @tport: tty port to shut down
 259  *
 260  * Shut down a USB serial port. Serialized against activate by the
 261  * tport mutex and kept to matching open/close pairs
 262  * of calls by the ASYNCB_INITIALIZED flag.
 263  *
 264  * Not called if tty is console.
 265  */
 266 static void serial_port_shutdown(struct tty_port *tport)
 267 {
 268         struct usb_serial_port *port =
 269                 container_of(tport, struct usb_serial_port, port);
 270         struct usb_serial_driver *drv = port->serial->type;
 271
 272         if (drv->close)
 273                 drv->close(port);
 274 }
 275
 276 static void serial_hangup(struct tty_struct *tty)
 277 {
 278         struct usb_serial_port *port = tty->driver_data;
 279
 280         dev_dbg(tty->dev, "%s\n", __func__);
 281
 282         tty_port_hangup(&port->port);
 283 }
 284
 285 static void serial_close(struct tty_struct *tty, struct file *filp)
 286 {
 287         struct usb_serial_port *port = tty->driver_data;
 288
 289         dev_dbg(tty->dev, "%s\n", __func__);
 290
 291         tty_port_close(&port->port, tty, filp);
 292 }
 293
 294 /**
 295  * serial_cleanup - free resources post close/hangup
 296  * @port: port to free up
 297  *
 298  * Do the resource freeing and refcount dropping for the port.
 299  * Avoid freeing the console.
 300  *
 301  * Called asynchronously after the last tty kref is dropped.
 302  */
 303 static void serial_cleanup(struct tty_struct *tty)
 304 {
 305         struct usb_serial_port *port = tty->driver_data;
 306         struct usb_serial *serial;
 307         struct module *owner;
 308
 309         dev_dbg(tty->dev, "%s\n", __func__);
 310
 311         /* The console is magical.  Do not hang up the console hardware
 312          * or there will be tears.
 313          */
 314         if (port->port.console)
 315                 return;
 316
 317         tty->driver_data = NULL;
 318
 319         serial = port->serial;
 320         owner = serial->type->driver.owner;
 321
 322         mutex_lock(&serial->disc_mutex);
 323         if (!serial->disconnected)
 324                 usb_autopm_put_interface(serial->interface);
 325         mutex_unlock(&serial->disc_mutex);
 326
 327         usb_serial_put(serial);
 328         module_put(owner);
 329 }
 330
 331 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
 332                                                                 int count)
 333 {
 334         struct usb_serial_port *port = tty->driver_data;
 335         int retval = -ENODEV;
 336
 337         if (port->serial->dev->state == USB_STATE_NOTATTACHED)
 338                 goto exit;
 339
 340         dev_dbg(tty->dev, "%s - %d byte(s)\n", __func__, count);
 341
 342         retval = port->serial->type->write(tty, port, buf, count);
 343         if (retval < 0)
 344                 retval = usb_translate_errors(retval);
 345 exit:
 346         return retval;
 347 }
 348
 349 static int serial_write_room(struct tty_struct *tty)
 350 {
 351         struct usb_serial_port *port = tty->driver_data;
 352
 353         dev_dbg(tty->dev, "%s\n", __func__);
 354
 355         return port->serial->type->write_room(tty);
 356 }
 357
 358 static int serial_chars_in_buffer(struct tty_struct *tty)
 359 {
 360         struct usb_serial_port *port = tty->driver_data;
 361         struct usb_serial *serial = port->serial;
 362
 363         dev_dbg(tty->dev, "%s\n", __func__);
 364
 365         if (serial->disconnected)
 366                 return 0;
 367
 368         return serial->type->chars_in_buffer(tty);
 369 }
 370
 371 static void serial_wait_until_sent(struct tty_struct *tty, int timeout)
 372 {
 373         struct usb_serial_port *port = tty->driver_data;
 374         struct usb_serial *serial = port->serial;
 375
 376         dev_dbg(tty->dev, "%s\n", __func__);
 377
 378         if (!port->serial->type->wait_until_sent)
 379                 return;
 380
 381         mutex_lock(&serial->disc_mutex);
 382         if (!serial->disconnected)
 383                 port->serial->type->wait_until_sent(tty, timeout);
 384         mutex_unlock(&serial->disc_mutex);
 385 }
 386
 387 static void serial_throttle(struct tty_struct *tty)
 388 {
 389         struct usb_serial_port *port = tty->driver_data;
 390
 391         dev_dbg(tty->dev, "%s\n", __func__);
 392
 393         if (port->serial->type->throttle)
 394                 port->serial->type->throttle(tty);
 395 }
 396
 397 static void serial_unthrottle(struct tty_struct *tty)
 398 {
 399         struct usb_serial_port *port = tty->driver_data;
 400
 401         dev_dbg(tty->dev, "%s\n", __func__);
 402
 403         if (port->serial->type->unthrottle)
 404                 port->serial->type->unthrottle(tty);
 405 }
 406
 407 static int serial_ioctl(struct tty_struct *tty,
 408                                         unsigned int cmd, unsigned long arg)
 409 {
 410         struct usb_serial_port *port = tty->driver_data;
 411         int retval = -ENOIOCTLCMD;
 412
 413         dev_dbg(tty->dev, "%s - cmd 0x%.4x\n", __func__, cmd);
 414
 415         switch (cmd) {
 416         case TIOCMIWAIT:
 417                 if (port->serial->type->tiocmiwait)
 418                         retval = port->serial->type->tiocmiwait(tty, arg);
 419                 break;
 420         default:
 421                 if (port->serial->type->ioctl)
 422                         retval = port->serial->type->ioctl(tty, cmd, arg);
 423         }
 424
 425         return retval;
 426 }
 427
 428 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 429 {
 430         struct usb_serial_port *port = tty->driver_data;
 431
 432         dev_dbg(tty->dev, "%s\n", __func__);
 433
 434         if (port->serial->type->set_termios)
 435                 port->serial->type->set_termios(tty, port, old);
 436         else
 437                 tty_termios_copy_hw(&tty->termios, old);
 438 }
 439
 440 static int serial_break(struct tty_struct *tty, int break_state)
 441 {
 442         struct usb_serial_port *port = tty->driver_data;
 443
 444         dev_dbg(tty->dev, "%s\n", __func__);
 445
 446         if (port->serial->type->break_ctl)
 447                 port->serial->type->break_ctl(tty, break_state);
 448
 449         return 0;
 450 }
 451
 452 static int serial_proc_show(struct seq_file *m, void *v)
 453 {
 454         struct usb_serial *serial;
 455         int i;
 456         char tmp[40];
 457
 458         seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
 459         for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
 460                 serial = usb_serial_get_by_index(i);
 461                 if (serial == NULL)
 462                         continue;
 463
 464                 seq_printf(m, "%d:", i);
 465                 if (serial->type->driver.owner)
 466                         seq_printf(m, " module:%s",
 467                                 module_name(serial->type->driver.owner));
 468                 seq_printf(m, " name:\"%s\"",
 469                                 serial->type->description);
 470                 seq_printf(m, " vendor:%04x product:%04x",
 471                         le16_to_cpu(serial->dev->descriptor.idVendor),
 472                         le16_to_cpu(serial->dev->descriptor.idProduct));
 473                 seq_printf(m, " num_ports:%d", serial->num_ports);
 474                 seq_printf(m, " port:%d", i - serial->minor + 1);
 475                 usb_make_path(serial->dev, tmp, sizeof(tmp));
 476                 seq_printf(m, " path:%s", tmp);
 477
 478                 seq_putc(m, '\n');
 479                 usb_serial_put(serial);
 480                 mutex_unlock(&serial->disc_mutex);
 481         }
 482         return 0;
 483 }
 484
 485 static int serial_proc_open(struct inode *inode, struct file *file)
 486 {
 487         return single_open(file, serial_proc_show, NULL);
 488 }
 489
 490 static const struct file_operations serial_proc_fops = {
 491         .owner          = THIS_MODULE,
 492         .open           = serial_proc_open,
 493         .read           = seq_read,
 494         .llseek         = seq_lseek,
 495         .release        = single_release,
 496 };
 497
 498 static int serial_tiocmget(struct tty_struct *tty)
 499 {
 500         struct usb_serial_port *port = tty->driver_data;
 501
 502         dev_dbg(tty->dev, "%s\n", __func__);
 503
 504         if (port->serial->type->tiocmget)
 505                 return port->serial->type->tiocmget(tty);
 506         return -EINVAL;
 507 }
 508
 509 static int serial_tiocmset(struct tty_struct *tty,
 510                             unsigned int set, unsigned int clear)
 511 {
 512         struct usb_serial_port *port = tty->driver_data;
 513
 514         dev_dbg(tty->dev, "%s\n", __func__);
 515
 516         if (port->serial->type->tiocmset)
 517                 return port->serial->type->tiocmset(tty, set, clear);
 518         return -EINVAL;
 519 }
 520
 521 static int serial_get_icount(struct tty_struct *tty,
 522                                 struct serial_icounter_struct *icount)
 523 {
 524         struct usb_serial_port *port = tty->driver_data;
 525
 526         dev_dbg(tty->dev, "%s\n", __func__);
 527
 528         if (port->serial->type->get_icount)
 529                 return port->serial->type->get_icount(tty, icount);
 530         return -EINVAL;
 531 }
 532
 533 /*
 534  * We would be calling tty_wakeup here, but unfortunately some line
 535  * disciplines have an annoying habit of calling tty->write from
 536  * the write wakeup callback (e.g. n_hdlc.c).
 537  */
 538 void usb_serial_port_softint(struct usb_serial_port *port)
 539 {
 540         schedule_work(&port->work);
 541 }
 542 EXPORT_SYMBOL_GPL(usb_serial_port_softint);
 543
 544 static void usb_serial_port_work(struct work_struct *work)
 545 {
 546         struct usb_serial_port *port =
 547                 container_of(work, struct usb_serial_port, work);
 548
 549         tty_port_tty_wakeup(&port->port);
 550 }
 551
 552 static void usb_serial_port_poison_urbs(struct usb_serial_port *port)
 553 {
 554         int i;
 555
 556         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 557                 usb_poison_urb(port->read_urbs[i]);
 558         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 559                 usb_poison_urb(port->write_urbs[i]);
 560
 561         usb_poison_urb(port->interrupt_in_urb);
 562         usb_poison_urb(port->interrupt_out_urb);
 563 }
 564
 565 static void usb_serial_port_unpoison_urbs(struct usb_serial_port *port)
 566 {
 567         int i;
 568
 569         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 570                 usb_unpoison_urb(port->read_urbs[i]);
 571         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 572                 usb_unpoison_urb(port->write_urbs[i]);
 573
 574         usb_unpoison_urb(port->interrupt_in_urb);
 575         usb_unpoison_urb(port->interrupt_out_urb);
 576 }
 577
 578 static void usb_serial_port_release(struct device *dev)
 579 {
 580         struct usb_serial_port *port = to_usb_serial_port(dev);
 581         int i;
 582
 583         dev_dbg(dev, "%s\n", __func__);
 584
 585         usb_free_urb(port->interrupt_in_urb);
 586         usb_free_urb(port->interrupt_out_urb);
 587         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 588                 usb_free_urb(port->read_urbs[i]);
 589                 kfree(port->bulk_in_buffers[i]);
 590         }
 591         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 592                 usb_free_urb(port->write_urbs[i]);
 593                 kfree(port->bulk_out_buffers[i]);
 594         }
 595         kfifo_free(&port->write_fifo);
 596         kfree(port->interrupt_in_buffer);
 597         kfree(port->interrupt_out_buffer);
 598         tty_port_destroy(&port->port);
 599         kfree(port);
 600 }
 601
 602 static struct usb_serial *create_serial(struct usb_device *dev,
 603                                         struct usb_interface *interface,
 604                                         struct usb_serial_driver *driver)
 605 {
 606         struct usb_serial *serial;
 607
 608         serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 609         if (!serial)
 610                 return NULL;
 611         serial->dev = usb_get_dev(dev);
 612         serial->type = driver;
 613         serial->interface = usb_get_intf(interface);
 614         kref_init(&serial->kref);
 615         mutex_init(&serial->disc_mutex);
 616         serial->minor = SERIAL_TTY_NO_MINOR;
 617
 618         return serial;
 619 }
 620
 621 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 622                                             struct usb_serial_driver *drv)
 623 {
 624         struct usb_dynid *dynid;
 625
 626         spin_lock(&drv->dynids.lock);
 627         list_for_each_entry(dynid, &drv->dynids.list, node) {
 628                 if (usb_match_one_id(intf, &dynid->id)) {
 629                         spin_unlock(&drv->dynids.lock);
 630                         return &dynid->id;
 631                 }
 632         }
 633         spin_unlock(&drv->dynids.lock);
 634         return NULL;
 635 }
 636
 637 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 638                                                 struct usb_interface *intf)
 639 {
 640         const struct usb_device_id *id;
 641
 642         id = usb_match_id(intf, drv->id_table);
 643         if (id) {
 644                 dev_dbg(&intf->dev, "static descriptor matches\n");
 645                 goto exit;
 646         }
 647         id = match_dynamic_id(intf, drv);
 648         if (id)
 649                 dev_dbg(&intf->dev, "dynamic descriptor matches\n");
 650 exit:
 651         return id;
 652 }
 653
 654 /* Caller must hold table_lock */
 655 static struct usb_serial_driver *search_serial_device(
 656                                         struct usb_interface *iface)
 657 {
 658         const struct usb_device_id *id = NULL;
 659         struct usb_serial_driver *drv;
 660         struct usb_driver *driver = to_usb_driver(iface->dev.driver);
 661
 662         /* Check if the usb id matches a known device */
 663         list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 664                 if (drv->usb_driver == driver)
 665                         id = get_iface_id(drv, iface);
 666                 if (id)
 667                         return drv;
 668         }
 669
 670         return NULL;
 671 }
 672
 673 static int serial_port_carrier_raised(struct tty_port *port)
 674 {
 675         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 676         struct usb_serial_driver *drv = p->serial->type;
 677
 678         if (drv->carrier_raised)
 679                 return drv->carrier_raised(p);
 680         /* No carrier control - don't block */
 681         return 1;
 682 }
 683
 684 static void serial_port_dtr_rts(struct tty_port *port, int on)
 685 {
 686         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 687         struct usb_serial *serial = p->serial;
 688         struct usb_serial_driver *drv = serial->type;
 689
 690         if (!drv->dtr_rts)
 691                 return;
 692         /*
 693          * Work-around bug in the tty-layer which can result in dtr_rts
 694          * being called after a disconnect (and tty_unregister_device
 695          * has returned). Remove once bug has been squashed.
 696          */
 697         mutex_lock(&serial->disc_mutex);
 698         if (!serial->disconnected)
 699                 drv->dtr_rts(p, on);
 700         mutex_unlock(&serial->disc_mutex);
 701 }
 702
 703 static const struct tty_port_operations serial_port_ops = {
 704         .carrier_raised         = serial_port_carrier_raised,
 705         .dtr_rts                = serial_port_dtr_rts,
 706         .activate               = serial_port_activate,
 707         .shutdown               = serial_port_shutdown,
 708 };
 709
 710 static int usb_serial_probe(struct usb_interface *interface,
 711                                const struct usb_device_id *id)
 712 {
 713         struct device *ddev = &interface->dev;
 714         struct usb_device *dev = interface_to_usbdev(interface);
 715         struct usb_serial *serial = NULL;
 716         struct usb_serial_port *port;
 717         struct usb_host_interface *iface_desc;
 718         struct usb_endpoint_descriptor *endpoint;
 719         struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
 720         struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
 721         struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
 722         struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 723         struct usb_serial_driver *type = NULL;
 724         int retval;
 725         unsigned int minor;
 726         int buffer_size;
 727         int i;
 728         int j;
 729         int num_interrupt_in = 0;
 730         int num_interrupt_out = 0;
 731         int num_bulk_in = 0;
 732         int num_bulk_out = 0;
 733         int num_ports = 0;
 734         int max_endpoints;
 735
 736         mutex_lock(&table_lock);
 737         type = search_serial_device(interface);
 738         if (!type) {
 739                 mutex_unlock(&table_lock);
 740                 dev_dbg(ddev, "none matched\n");
 741                 return -ENODEV;
 742         }
 743
 744         if (!try_module_get(type->driver.owner)) {
 745                 mutex_unlock(&table_lock);
 746                 dev_err(ddev, "module get failed, exiting\n");
 747                 return -EIO;
 748         }
 749         mutex_unlock(&table_lock);
 750
 751         serial = create_serial(dev, interface, type);
 752         if (!serial) {
 753                 module_put(type->driver.owner);
 754                 return -ENOMEM;
 755         }
 756
 757         /* if this device type has a probe function, call it */
 758         if (type->probe) {
 759                 const struct usb_device_id *id;
 760
 761                 id = get_iface_id(type, interface);
 762                 retval = type->probe(serial, id);
 763
 764                 if (retval) {
 765                         dev_dbg(ddev, "sub driver rejected device\n");
 766                         usb_serial_put(serial);
 767                         module_put(type->driver.owner);
 768                         return retval;
 769                 }
 770         }
 771
 772         /* descriptor matches, let's find the endpoints needed */
 773         /* check out the endpoints */
 774         iface_desc = interface->cur_altsetting;
 775         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 776                 endpoint = &iface_desc->endpoint[i].desc;
 777
 778                 if (usb_endpoint_is_bulk_in(endpoint)) {
 779                         /* we found a bulk in endpoint */
 780                         dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
 781                         if (num_bulk_in < MAX_NUM_PORTS) {
 782                                 bulk_in_endpoint[num_bulk_in] = endpoint;
 783                                 ++num_bulk_in;
 784                         }
 785                 }
 786
 787                 if (usb_endpoint_is_bulk_out(endpoint)) {
 788                         /* we found a bulk out endpoint */
 789                         dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
 790                         if (num_bulk_out < MAX_NUM_PORTS) {
 791                                 bulk_out_endpoint[num_bulk_out] = endpoint;
 792                                 ++num_bulk_out;
 793                         }
 794                 }
 795
 796                 if (usb_endpoint_is_int_in(endpoint)) {
 797                         /* we found a interrupt in endpoint */
 798                         dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
 799                         if (num_interrupt_in < MAX_NUM_PORTS) {
 800                                 interrupt_in_endpoint[num_interrupt_in] =
 801                                                 endpoint;
 802                                 ++num_interrupt_in;
 803                         }
 804                 }
 805
 806                 if (usb_endpoint_is_int_out(endpoint)) {
 807                         /* we found an interrupt out endpoint */
 808                         dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
 809                         if (num_interrupt_out < MAX_NUM_PORTS) {
 810                                 interrupt_out_endpoint[num_interrupt_out] =
 811                                                 endpoint;
 812                                 ++num_interrupt_out;
 813                         }
 814                 }
 815         }
 816
 817 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 818         /* BEGIN HORRIBLE HACK FOR PL2303 */
 819         /* this is needed due to the looney way its endpoints are set up */
 820         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 821              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 822             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 823              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 824             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 825              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 826             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 827              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 828                 if (interface != dev->actconfig->interface[0]) {
 829                         /* check out the endpoints of the other interface*/
 830                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 831                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 832                                 endpoint = &iface_desc->endpoint[i].desc;
 833                                 if (usb_endpoint_is_int_in(endpoint)) {
 834                                         /* we found a interrupt in endpoint */
 835                                         dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
 836                                         if (num_interrupt_in < MAX_NUM_PORTS) {
 837                                                 interrupt_in_endpoint[num_interrupt_in] = endpoint;
 838                                                 ++num_interrupt_in;
 839                                         }
 840                                 }
 841                         }
 842                 }
 843
 844                 /* Now make sure the PL-2303 is configured correctly.
 845                  * If not, give up now and hope this hack will work
 846                  * properly during a later invocation of usb_serial_probe
 847                  */
 848                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 849                         dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 850                         usb_serial_put(serial);
 851                         module_put(type->driver.owner);
 852                         return -ENODEV;
 853                 }
 854         }
 855         /* END HORRIBLE HACK FOR PL2303 */
 856 #endif
 857
 858 #ifdef CONFIG_USB_SERIAL_GENERIC
 859         if (type == &usb_serial_generic_device) {
 860                 num_ports = num_bulk_out;
 861                 if (num_ports == 0) {
 862                         dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
 863                         usb_serial_put(serial);
 864                         module_put(type->driver.owner);
 865                         return -EIO;
 866                 }
 867                 dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
 868                 dev_info(ddev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n");
 869         }
 870 #endif
 871         if (!num_ports) {
 872                 /* if this device type has a calc_num_ports function, call it */
 873                 if (type->calc_num_ports)
 874                         num_ports = type->calc_num_ports(serial);
 875                 if (!num_ports)
 876                         num_ports = type->num_ports;
 877         }
 878
 879         serial->num_ports = num_ports;
 880         serial->num_bulk_in = num_bulk_in;
 881         serial->num_bulk_out = num_bulk_out;
 882         serial->num_interrupt_in = num_interrupt_in;
 883         serial->num_interrupt_out = num_interrupt_out;
 884
 885         /* found all that we need */
 886         dev_info(ddev, "%s converter detected\n", type->description);
 887
 888         /* create our ports, we need as many as the max endpoints */
 889         /* we don't use num_ports here because some devices have more
 890            endpoint pairs than ports */
 891         max_endpoints = max(num_bulk_in, num_bulk_out);
 892         max_endpoints = max(max_endpoints, num_interrupt_in);
 893         max_endpoints = max(max_endpoints, num_interrupt_out);
 894         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 895         serial->num_port_pointers = max_endpoints;
 896
 897         dev_dbg(ddev, "setting up %d port structures for this device", max_endpoints);
 898         for (i = 0; i < max_endpoints; ++i) {
 899                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 900                 if (!port)
 901                         goto probe_error;
 902                 tty_port_init(&port->port);
 903                 port->port.ops = &serial_port_ops;
 904                 port->serial = serial;
 905                 spin_lock_init(&port->lock);
 906                 /* Keep this for private driver use for the moment but
 907                    should probably go away */
 908                 INIT_WORK(&port->work, usb_serial_port_work);
 909                 serial->port[i] = port;
 910                 port->dev.parent = &interface->dev;
 911                 port->dev.driver = NULL;
 912                 port->dev.bus = &usb_serial_bus_type;
 913                 port->dev.release = &usb_serial_port_release;
 914                 device_initialize(&port->dev);
 915         }
 916
 917         /* set up the endpoint information */
 918         for (i = 0; i < num_bulk_in; ++i) {
 919                 endpoint = bulk_in_endpoint[i];
 920                 port = serial->port[i];
 921                 buffer_size = max_t(int, serial->type->bulk_in_size,
 922                                 usb_endpoint_maxp(endpoint));
 923                 port->bulk_in_size = buffer_size;
 924                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 925
 926                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 927                         set_bit(j, &port->read_urbs_free);
 928                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 929                         if (!port->read_urbs[j])
 930                                 goto probe_error;
 931                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 932                                                                 GFP_KERNEL);
 933                         if (!port->bulk_in_buffers[j])
 934                                 goto probe_error;
 935                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 936                                         usb_rcvbulkpipe(dev,
 937                                                 endpoint->bEndpointAddress),
 938                                         port->bulk_in_buffers[j], buffer_size,
 939                                         serial->type->read_bulk_callback,
 940                                         port);
 941                 }
 942
 943                 port->read_urb = port->read_urbs[0];
 944                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 945         }
 946
 947         for (i = 0; i < num_bulk_out; ++i) {
 948                 endpoint = bulk_out_endpoint[i];
 949                 port = serial->port[i];
 950                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 951                         goto probe_error;
 952                 buffer_size = serial->type->bulk_out_size;
 953                 if (!buffer_size)
 954                         buffer_size = usb_endpoint_maxp(endpoint);
 955                 port->bulk_out_size = buffer_size;
 956                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 957
 958                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 959                         set_bit(j, &port->write_urbs_free);
 960                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 961                         if (!port->write_urbs[j])
 962                                 goto probe_error;
 963                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 964                                                                 GFP_KERNEL);
 965                         if (!port->bulk_out_buffers[j])
 966                                 goto probe_error;
 967                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 968                                         usb_sndbulkpipe(dev,
 969                                                 endpoint->bEndpointAddress),
 970                                         port->bulk_out_buffers[j], buffer_size,
 971                                         serial->type->write_bulk_callback,
 972                                         port);
 973                 }
 974
 975                 port->write_urb = port->write_urbs[0];
 976                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 977         }
 978
 979         if (serial->type->read_int_callback) {
 980                 for (i = 0; i < num_interrupt_in; ++i) {
 981                         endpoint = interrupt_in_endpoint[i];
 982                         port = serial->port[i];
 983                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 984                         if (!port->interrupt_in_urb)
 985                                 goto probe_error;
 986                         buffer_size = usb_endpoint_maxp(endpoint);
 987                         port->interrupt_in_endpointAddress =
 988                                                 endpoint->bEndpointAddress;
 989                         port->interrupt_in_buffer = kmalloc(buffer_size,
 990                                                                 GFP_KERNEL);
 991                         if (!port->interrupt_in_buffer)
 992                                 goto probe_error;
 993                         usb_fill_int_urb(port->interrupt_in_urb, dev,
 994                                 usb_rcvintpipe(dev,
 995                                                 endpoint->bEndpointAddress),
 996                                 port->interrupt_in_buffer, buffer_size,
 997                                 serial->type->read_int_callback, port,
 998                                 endpoint->bInterval);
 999                 }
1000         } else if (num_interrupt_in) {
1001                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1002         }
1003
1004         if (serial->type->write_int_callback) {
1005                 for (i = 0; i < num_interrupt_out; ++i) {
1006                         endpoint = interrupt_out_endpoint[i];
1007                         port = serial->port[i];
1008                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1009                         if (!port->interrupt_out_urb)
1010                                 goto probe_error;
1011                         buffer_size = usb_endpoint_maxp(endpoint);
1012                         port->interrupt_out_size = buffer_size;
1013                         port->interrupt_out_endpointAddress =
1014                                                 endpoint->bEndpointAddress;
1015                         port->interrupt_out_buffer = kmalloc(buffer_size,
1016                                                                 GFP_KERNEL);
1017                         if (!port->interrupt_out_buffer)
1018                                 goto probe_error;
1019                         usb_fill_int_urb(port->interrupt_out_urb, dev,
1020                                 usb_sndintpipe(dev,
1021                                                   endpoint->bEndpointAddress),
1022                                 port->interrupt_out_buffer, buffer_size,
1023                                 serial->type->write_int_callback, port,
1024                                 endpoint->bInterval);
1025                 }
1026         } else if (num_interrupt_out) {
1027                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1028         }
1029
1030         usb_set_intfdata(interface, serial);
1031
1032         /* if this device type has an attach function, call it */
1033         if (type->attach) {
1034                 retval = type->attach(serial);
1035                 if (retval < 0)
1036                         goto probe_error;
1037                 serial->attached = 1;
1038                 if (retval > 0) {
1039                         /* quietly accept this device, but don't bind to a
1040                            serial port as it's about to disappear */
1041                         serial->num_ports = 0;
1042                         goto exit;
1043                 }
1044         } else {
1045                 serial->attached = 1;
1046         }
1047
1048         /* Avoid race with tty_open and serial_install by setting the
1049          * disconnected flag and not clearing it until all ports have been
1050          * registered.
1051          */
1052         serial->disconnected = 1;
1053
1054         if (get_free_serial(serial, num_ports, &minor) == NULL) {
1055                 dev_err(ddev, "No more free serial devices\n");
1056                 goto probe_error;
1057         }
1058         serial->minor = minor;
1059
1060         /* register all of the individual ports with the driver core */
1061         for (i = 0; i < num_ports; ++i) {
1062                 port = serial->port[i];
1063                 dev_set_name(&port->dev, "ttyUSB%d", port->number);
1064                 dev_dbg(ddev, "registering %s", dev_name(&port->dev));
1065                 device_enable_async_suspend(&port->dev);
1066
1067                 retval = device_add(&port->dev);
1068                 if (retval)
1069                         dev_err(ddev, "Error registering port device, continuing\n");
1070         }
1071
1072         serial->disconnected = 0;
1073
1074         usb_serial_console_init(minor);
1075 exit:
1076         module_put(type->driver.owner);
1077         return 0;
1078
1079 probe_error:
1080         usb_serial_put(serial);
1081         module_put(type->driver.owner);
1082         return -EIO;
1083 }
1084
1085 static void usb_serial_disconnect(struct usb_interface *interface)
1086 {
1087         int i;
1088         struct usb_serial *serial = usb_get_intfdata(interface);
1089         struct device *dev = &interface->dev;
1090         struct usb_serial_port *port;
1091
1092         usb_serial_console_disconnect(serial);
1093
1094         mutex_lock(&serial->disc_mutex);
1095         /* must set a flag, to signal subdrivers */
1096         serial->disconnected = 1;
1097         mutex_unlock(&serial->disc_mutex);
1098
1099         for (i = 0; i < serial->num_ports; ++i) {
1100                 port = serial->port[i];
1101                 if (port) {
1102                         struct tty_struct *tty = tty_port_tty_get(&port->port);
1103                         if (tty) {
1104                                 tty_vhangup(tty);
1105                                 tty_kref_put(tty);
1106                         }
1107                         usb_serial_port_poison_urbs(port);
1108                         wake_up_interruptible(&port->port.delta_msr_wait);
1109                         cancel_work_sync(&port->work);
1110                         if (device_is_registered(&port->dev))
1111                                 device_del(&port->dev);
1112                 }
1113         }
1114         if (serial->type->disconnect)
1115                 serial->type->disconnect(serial);
1116
1117         /* let the last holder of this object cause it to be cleaned up */
1118         usb_serial_put(serial);
1119         dev_info(dev, "device disconnected\n");
1120 }
1121
1122 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1123 {
1124         struct usb_serial *serial = usb_get_intfdata(intf);
1125         struct usb_serial_port *port;
1126         int i, r = 0;
1127
1128         serial->suspending = 1;
1129
1130         /*
1131          * serial->type->suspend() MUST return 0 in system sleep context,
1132          * otherwise, the resume callback has to recover device from
1133          * previous suspend failure.
1134          */
1135         if (serial->type->suspend) {
1136                 r = serial->type->suspend(serial, message);
1137                 if (r < 0) {
1138                         serial->suspending = 0;
1139                         goto err_out;
1140                 }
1141         }
1142
1143         for (i = 0; i < serial->num_ports; ++i) {
1144                 port = serial->port[i];
1145                 if (port)
1146                         usb_serial_port_poison_urbs(port);
1147         }
1148
1149 err_out:
1150         return r;
1151 }
1152 EXPORT_SYMBOL(usb_serial_suspend);
1153
1154 static void usb_serial_unpoison_port_urbs(struct usb_serial *serial)
1155 {
1156         struct usb_serial_port *port;
1157         int i;
1158
1159         for (i = 0; i < serial->num_ports; ++i) {
1160                 port = serial->port[i];
1161                 if (port)
1162                         usb_serial_port_unpoison_urbs(port);
1163         }
1164 }
1165
1166 int usb_serial_resume(struct usb_interface *intf)
1167 {
1168         struct usb_serial *serial = usb_get_intfdata(intf);
1169         int rv;
1170
1171         usb_serial_unpoison_port_urbs(serial);
1172
1173         serial->suspending = 0;
1174         if (serial->type->resume)
1175                 rv = serial->type->resume(serial);
1176         else
1177                 rv = usb_serial_generic_resume(serial);
1178
1179         return rv;
1180 }
1181 EXPORT_SYMBOL(usb_serial_resume);
1182
1183 static int usb_serial_reset_resume(struct usb_interface *intf)
1184 {
1185         struct usb_serial *serial = usb_get_intfdata(intf);
1186         int rv;
1187
1188         usb_serial_unpoison_port_urbs(serial);
1189
1190         serial->suspending = 0;
1191         if (serial->type->reset_resume)
1192                 rv = serial->type->reset_resume(serial);
1193         else {
1194                 rv = -EOPNOTSUPP;
1195                 intf->needs_binding = 1;
1196         }
1197
1198         return rv;
1199 }
1200
1201 static const struct tty_operations serial_ops = {
1202         .open =                 serial_open,
1203         .close =                serial_close,
1204         .write =                serial_write,
1205         .hangup =               serial_hangup,
1206         .write_room =           serial_write_room,
1207         .ioctl =                serial_ioctl,
1208         .set_termios =          serial_set_termios,
1209         .throttle =             serial_throttle,
1210         .unthrottle =           serial_unthrottle,
1211         .break_ctl =            serial_break,
1212         .chars_in_buffer =      serial_chars_in_buffer,
1213         .wait_until_sent =      serial_wait_until_sent,
1214         .tiocmget =             serial_tiocmget,
1215         .tiocmset =             serial_tiocmset,
1216         .get_icount =           serial_get_icount,
1217         .cleanup =              serial_cleanup,
1218         .install =              serial_install,
1219         .proc_fops =            &serial_proc_fops,
1220 };
1221
1222
1223 struct tty_driver *usb_serial_tty_driver;
1224
1225 /* Driver structure we register with the USB core */
1226 static struct usb_driver usb_serial_driver = {
1227         .name =         "usbserial",
1228         .probe =        usb_serial_probe,
1229         .disconnect =   usb_serial_disconnect,
1230         .suspend =      usb_serial_suspend,
1231         .resume =       usb_serial_resume,
1232         .no_dynamic_id =        1,
1233         .supports_autosuspend = 1,
1234 };
1235
1236 static int __init usb_serial_init(void)
1237 {
1238         int i;
1239         int result;
1240
1241         usb_serial_tty_driver = alloc_tty_driver(SERIAL_TTY_MINORS);
1242         if (!usb_serial_tty_driver)
1243                 return -ENOMEM;
1244
1245         /* Initialize our global data */
1246         for (i = 0; i < SERIAL_TTY_MINORS; ++i)
1247                 serial_table[i] = NULL;
1248
1249         result = bus_register(&usb_serial_bus_type);
1250         if (result) {
1251                 pr_err("%s - registering bus driver failed\n", __func__);
1252                 goto exit_bus;
1253         }
1254
1255         usb_serial_tty_driver->driver_name = "usbserial";
1256         usb_serial_tty_driver->name = "ttyUSB";
1257         usb_serial_tty_driver->major = SERIAL_TTY_MAJOR;
1258         usb_serial_tty_driver->minor_start = 0;
1259         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1260         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1261         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1262                                                 TTY_DRIVER_DYNAMIC_DEV;
1263         usb_serial_tty_driver->init_termios = tty_std_termios;
1264         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1265                                                         | HUPCL | CLOCAL;
1266         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1267         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1268         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1269         result = tty_register_driver(usb_serial_tty_driver);
1270         if (result) {
1271                 pr_err("%s - tty_register_driver failed\n", __func__);
1272                 goto exit_reg_driver;
1273         }
1274
1275         /* register the USB driver */
1276         result = usb_register(&usb_serial_driver);
1277         if (result < 0) {
1278                 pr_err("%s - usb_register failed\n", __func__);
1279                 goto exit_tty;
1280         }
1281
1282         /* register the generic driver, if we should */
1283         result = usb_serial_generic_register();
1284         if (result < 0) {
1285                 pr_err("%s - registering generic driver failed\n", __func__);
1286                 goto exit_generic;
1287         }
1288
1289         return result;
1290
1291 exit_generic:
1292         usb_deregister(&usb_serial_driver);
1293
1294 exit_tty:
1295         tty_unregister_driver(usb_serial_tty_driver);
1296
1297 exit_reg_driver:
1298         bus_unregister(&usb_serial_bus_type);
1299
1300 exit_bus:
1301         pr_err("%s - returning with error %d\n", __func__, result);
1302         put_tty_driver(usb_serial_tty_driver);
1303         return result;
1304 }
1305
1306
1307 static void __exit usb_serial_exit(void)
1308 {
1309         usb_serial_console_exit();
1310
1311         usb_serial_generic_deregister();
1312
1313         usb_deregister(&usb_serial_driver);
1314         tty_unregister_driver(usb_serial_tty_driver);
1315         put_tty_driver(usb_serial_tty_driver);
1316         bus_unregister(&usb_serial_bus_type);
1317 }
1318
1319
1320 module_init(usb_serial_init);
1321 module_exit(usb_serial_exit);
1322
1323 #define set_to_generic_if_null(type, function)                          \
1324         do {                                                            \
1325                 if (!type->function) {                                  \
1326                         type->function = usb_serial_generic_##function; \
1327                         pr_debug("%s: using generic " #function "\n",   \
1328                                                 type->driver.name);     \
1329                 }                                                       \
1330         } while (0)
1331
1332 static void usb_serial_operations_init(struct usb_serial_driver *device)
1333 {
1334         set_to_generic_if_null(device, open);
1335         set_to_generic_if_null(device, write);
1336         set_to_generic_if_null(device, close);
1337         set_to_generic_if_null(device, write_room);
1338         set_to_generic_if_null(device, chars_in_buffer);
1339         if (device->tx_empty)
1340                 set_to_generic_if_null(device, wait_until_sent);
1341         set_to_generic_if_null(device, read_bulk_callback);
1342         set_to_generic_if_null(device, write_bulk_callback);
1343         set_to_generic_if_null(device, process_read_urb);
1344         set_to_generic_if_null(device, prepare_write_buffer);
1345 }
1346
1347 static int usb_serial_register(struct usb_serial_driver *driver)
1348 {
1349         int retval;
1350
1351         if (usb_disabled())
1352                 return -ENODEV;
1353
1354         if (!driver->description)
1355                 driver->description = driver->driver.name;
1356         if (!driver->usb_driver) {
1357                 WARN(1, "Serial driver %s has no usb_driver\n",
1358                                 driver->description);
1359                 return -EINVAL;
1360         }
1361
1362         usb_serial_operations_init(driver);
1363
1364         /* Add this device to our list of devices */
1365         mutex_lock(&table_lock);
1366         list_add(&driver->driver_list, &usb_serial_driver_list);
1367
1368         retval = usb_serial_bus_register(driver);
1369         if (retval) {
1370                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1371                 list_del(&driver->driver_list);
1372         } else
1373                 pr_info("USB Serial support registered for %s\n", driver->description);
1374
1375         mutex_unlock(&table_lock);
1376         return retval;
1377 }
1378
1379 static void usb_serial_deregister(struct usb_serial_driver *device)
1380 {
1381         pr_info("USB Serial deregistering driver %s\n", device->description);
1382
1383         mutex_lock(&table_lock);
1384         list_del(&device->driver_list);
1385         mutex_unlock(&table_lock);
1386
1387         usb_serial_bus_deregister(device);
1388 }
1389
1390 /**
1391  * usb_serial_register_drivers - register drivers for a usb-serial module
1392  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1393  * @name: name of the usb_driver for this set of @serial_drivers
1394  * @id_table: list of all devices this @serial_drivers set binds to
1395  *
1396  * Registers all the drivers in the @serial_drivers array, and dynamically
1397  * creates a struct usb_driver with the name @name and id_table of @id_table.
1398  */
1399 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1400                                 const char *name,
1401                                 const struct usb_device_id *id_table)
1402 {
1403         int rc;
1404         struct usb_driver *udriver;
1405         struct usb_serial_driver * const *sd;
1406
1407         /*
1408          * udriver must be registered before any of the serial drivers,
1409          * because the store_new_id() routine for the serial drivers (in
1410          * bus.c) probes udriver.
1411          *
1412          * Performance hack: We don't want udriver to be probed until
1413          * the serial drivers are registered, because the probe would
1414          * simply fail for lack of a matching serial driver.
1415          * So we leave udriver's id_table set to NULL until we are all set.
1416          *
1417          * Suspend/resume support is implemented in the usb-serial core,
1418          * so fill in the PM-related fields in udriver.
1419          */
1420         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1421         if (!udriver)
1422                 return -ENOMEM;
1423
1424         udriver->name = name;
1425         udriver->no_dynamic_id = 1;
1426         udriver->supports_autosuspend = 1;
1427         udriver->suspend = usb_serial_suspend;
1428         udriver->resume = usb_serial_resume;
1429         udriver->probe = usb_serial_probe;
1430         udriver->disconnect = usb_serial_disconnect;
1431
1432         /* we only set the reset_resume field if the serial_driver has one */
1433         for (sd = serial_drivers; *sd; ++sd) {
1434                 if ((*sd)->reset_resume) {
1435                         udriver->reset_resume = usb_serial_reset_resume;
1436                         break;
1437                 }
1438         }
1439
1440         rc = usb_register(udriver);
1441         if (rc)
1442                 return rc;
1443
1444         for (sd = serial_drivers; *sd; ++sd) {
1445                 (*sd)->usb_driver = udriver;
1446                 rc = usb_serial_register(*sd);
1447                 if (rc)
1448                         goto failed;
1449         }
1450
1451         /* Now set udriver's id_table and look for matches */
1452         udriver->id_table = id_table;
1453         rc = driver_attach(&udriver->drvwrap.driver);
1454         return 0;
1455
1456  failed:
1457         while (sd-- > serial_drivers)
1458                 usb_serial_deregister(*sd);
1459         usb_deregister(udriver);
1460         return rc;
1461 }
1462 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1463
1464 /**
1465  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1466  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1467  *
1468  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1469  * frees the struct usb_driver that was created by the call to
1470  * usb_serial_register_drivers().
1471  */
1472 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1473 {
1474         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1475
1476         for (; *serial_drivers; ++serial_drivers)
1477                 usb_serial_deregister(*serial_drivers);
1478         usb_deregister(udriver);
1479         kfree(udriver);
1480 }
1481 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1482
1483 MODULE_AUTHOR(DRIVER_AUTHOR);
1484 MODULE_DESCRIPTION(DRIVER_DESC);
1485 MODULE_LICENSE("GPL");