drivers/usb/serial/usb-serial.c

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