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 <linux/idr.h>
  41
  42 #define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
  43 #define DRIVER_DESC "USB Serial Driver core"
  44
  45 #define USB_SERIAL_TTY_MAJOR    188
  46 #define USB_SERIAL_TTY_MINORS   512     /* should be enough for a while */
  47
  48 /* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
  49    the MODULE_DEVICE_TABLE declarations in each serial driver
  50    cause the "hotplug" program to pull in whatever module is necessary
  51    via modprobe, and modprobe will load usbserial because the serial
  52    drivers depend on it.
  53 */
  54
  55 static DEFINE_IDR(serial_minors);
  56 static DEFINE_MUTEX(table_lock);
  57 static LIST_HEAD(usb_serial_driver_list);
  58
  59 /*
  60  * Look up the serial port structure.  If it is found and it hasn't been
  61  * disconnected, return with the parent usb_serial structure's disc_mutex held
  62  * and its refcount incremented.  Otherwise return NULL.
  63  */
  64 struct usb_serial_port *usb_serial_port_get_by_minor(unsigned minor)
  65 {
  66         struct usb_serial *serial;
  67         struct usb_serial_port *port;
  68
  69         mutex_lock(&table_lock);
  70         port = idr_find(&serial_minors, minor);
  71         if (!port)
  72                 goto exit;
  73
  74         serial = port->serial;
  75         mutex_lock(&serial->disc_mutex);
  76         if (serial->disconnected) {
  77                 mutex_unlock(&serial->disc_mutex);
  78                 port = NULL;
  79         } else {
  80                 kref_get(&serial->kref);
  81         }
  82 exit:
  83         mutex_unlock(&table_lock);
  84         return port;
  85 }
  86
  87 static int allocate_minors(struct usb_serial *serial, int num_ports)
  88 {
  89         struct usb_serial_port *port;
  90         unsigned int i, j;
  91         int minor;
  92
  93         dev_dbg(&serial->interface->dev, "%s %d\n", __func__, num_ports);
  94
  95         mutex_lock(&table_lock);
  96         for (i = 0; i < num_ports; ++i) {
  97                 port = serial->port[i];
  98                 minor = idr_alloc(&serial_minors, port, 0,
  99                                         USB_SERIAL_TTY_MINORS, 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 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 ssize_t port_number_show(struct device *dev,
 691                                 struct device_attribute *attr, char *buf)
 692 {
 693         struct usb_serial_port *port = to_usb_serial_port(dev);
 694
 695         return sprintf(buf, "%u\n", port->port_number);
 696 }
 697 static DEVICE_ATTR_RO(port_number);
 698
 699 static struct attribute *usb_serial_port_attrs[] = {
 700         &dev_attr_port_number.attr,
 701         NULL
 702 };
 703 ATTRIBUTE_GROUPS(usb_serial_port);
 704
 705 static const struct tty_port_operations serial_port_ops = {
 706         .carrier_raised         = serial_port_carrier_raised,
 707         .dtr_rts                = serial_port_dtr_rts,
 708         .activate               = serial_port_activate,
 709         .shutdown               = serial_port_shutdown,
 710 };
 711
 712 static void find_endpoints(struct usb_serial *serial,
 713                                         struct usb_serial_endpoints *epds)
 714 {
 715         struct device *dev = &serial->interface->dev;
 716         struct usb_host_interface *iface_desc;
 717         struct usb_endpoint_descriptor *epd;
 718         unsigned int i;
 719
 720         BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_in) < USB_MAXENDPOINTS / 2);
 721         BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < USB_MAXENDPOINTS / 2);
 722         BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_in) < USB_MAXENDPOINTS / 2);
 723         BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_out) < USB_MAXENDPOINTS / 2);
 724
 725         iface_desc = serial->interface->cur_altsetting;
 726         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 727                 epd = &iface_desc->endpoint[i].desc;
 728
 729                 if (usb_endpoint_is_bulk_in(epd)) {
 730                         dev_dbg(dev, "found bulk in on endpoint %u\n", i);
 731                         epds->bulk_in[epds->num_bulk_in++] = epd;
 732                 } else if (usb_endpoint_is_bulk_out(epd)) {
 733                         dev_dbg(dev, "found bulk out on endpoint %u\n", i);
 734                         epds->bulk_out[epds->num_bulk_out++] = epd;
 735                 } else if (usb_endpoint_is_int_in(epd)) {
 736                         dev_dbg(dev, "found interrupt in on endpoint %u\n", i);
 737                         epds->interrupt_in[epds->num_interrupt_in++] = epd;
 738                 } else if (usb_endpoint_is_int_out(epd)) {
 739                         dev_dbg(dev, "found interrupt out on endpoint %u\n", i);
 740                         epds->interrupt_out[epds->num_interrupt_out++] = epd;
 741                 }
 742         }
 743 }
 744
 745 static int setup_port_bulk_in(struct usb_serial_port *port,
 746                                         struct usb_endpoint_descriptor *epd)
 747 {
 748         struct usb_serial_driver *type = port->serial->type;
 749         struct usb_device *udev = port->serial->dev;
 750         int buffer_size;
 751         int i;
 752
 753         buffer_size = max_t(int, type->bulk_in_size, usb_endpoint_maxp(epd));
 754         port->bulk_in_size = buffer_size;
 755         port->bulk_in_endpointAddress = epd->bEndpointAddress;
 756
 757         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 758                 set_bit(i, &port->read_urbs_free);
 759                 port->read_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
 760                 if (!port->read_urbs[i])
 761                         return -ENOMEM;
 762                 port->bulk_in_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
 763                 if (!port->bulk_in_buffers[i])
 764                         return -ENOMEM;
 765                 usb_fill_bulk_urb(port->read_urbs[i], udev,
 766                                 usb_rcvbulkpipe(udev, epd->bEndpointAddress),
 767                                 port->bulk_in_buffers[i], buffer_size,
 768                                 type->read_bulk_callback, port);
 769         }
 770
 771         port->read_urb = port->read_urbs[0];
 772         port->bulk_in_buffer = port->bulk_in_buffers[0];
 773
 774         return 0;
 775 }
 776
 777 static int setup_port_bulk_out(struct usb_serial_port *port,
 778                                         struct usb_endpoint_descriptor *epd)
 779 {
 780         struct usb_serial_driver *type = port->serial->type;
 781         struct usb_device *udev = port->serial->dev;
 782         int buffer_size;
 783         int i;
 784
 785         if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 786                 return -ENOMEM;
 787         if (type->bulk_out_size)
 788                 buffer_size = type->bulk_out_size;
 789         else
 790                 buffer_size = usb_endpoint_maxp(epd);
 791         port->bulk_out_size = buffer_size;
 792         port->bulk_out_endpointAddress = epd->bEndpointAddress;
 793
 794         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 795                 set_bit(i, &port->write_urbs_free);
 796                 port->write_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
 797                 if (!port->write_urbs[i])
 798                         return -ENOMEM;
 799                 port->bulk_out_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
 800                 if (!port->bulk_out_buffers[i])
 801                         return -ENOMEM;
 802                 usb_fill_bulk_urb(port->write_urbs[i], udev,
 803                                 usb_sndbulkpipe(udev, epd->bEndpointAddress),
 804                                 port->bulk_out_buffers[i], buffer_size,
 805                                 type->write_bulk_callback, port);
 806         }
 807
 808         port->write_urb = port->write_urbs[0];
 809         port->bulk_out_buffer = port->bulk_out_buffers[0];
 810
 811         return 0;
 812 }
 813
 814 static int setup_port_interrupt_in(struct usb_serial_port *port,
 815                                         struct usb_endpoint_descriptor *epd)
 816 {
 817         struct usb_serial_driver *type = port->serial->type;
 818         struct usb_device *udev = port->serial->dev;
 819         int buffer_size;
 820
 821         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 822         if (!port->interrupt_in_urb)
 823                 return -ENOMEM;
 824         buffer_size = usb_endpoint_maxp(epd);
 825         port->interrupt_in_endpointAddress = epd->bEndpointAddress;
 826         port->interrupt_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
 827         if (!port->interrupt_in_buffer)
 828                 return -ENOMEM;
 829         usb_fill_int_urb(port->interrupt_in_urb, udev,
 830                         usb_rcvintpipe(udev, epd->bEndpointAddress),
 831                         port->interrupt_in_buffer, buffer_size,
 832                         type->read_int_callback, port,
 833                         epd->bInterval);
 834
 835         return 0;
 836 }
 837
 838 static int setup_port_interrupt_out(struct usb_serial_port *port,
 839                                         struct usb_endpoint_descriptor *epd)
 840 {
 841         struct usb_serial_driver *type = port->serial->type;
 842         struct usb_device *udev = port->serial->dev;
 843         int buffer_size;
 844
 845         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 846         if (!port->interrupt_out_urb)
 847                 return -ENOMEM;
 848         buffer_size = usb_endpoint_maxp(epd);
 849         port->interrupt_out_size = buffer_size;
 850         port->interrupt_out_endpointAddress = epd->bEndpointAddress;
 851         port->interrupt_out_buffer = kmalloc(buffer_size, GFP_KERNEL);
 852         if (!port->interrupt_out_buffer)
 853                 return -ENOMEM;
 854         usb_fill_int_urb(port->interrupt_out_urb, udev,
 855                         usb_sndintpipe(udev, epd->bEndpointAddress),
 856                         port->interrupt_out_buffer, buffer_size,
 857                         type->write_int_callback, port,
 858                         epd->bInterval);
 859
 860         return 0;
 861 }
 862
 863 static int usb_serial_probe(struct usb_interface *interface,
 864                                const struct usb_device_id *id)
 865 {
 866         struct device *ddev = &interface->dev;
 867         struct usb_device *dev = interface_to_usbdev(interface);
 868         struct usb_serial *serial = NULL;
 869         struct usb_serial_port *port;
 870         struct usb_serial_endpoints *epds;
 871         struct usb_serial_driver *type = NULL;
 872         int retval;
 873         int i;
 874         int num_ports = 0;
 875         unsigned char max_endpoints;
 876
 877         mutex_lock(&table_lock);
 878         type = search_serial_device(interface);
 879         if (!type) {
 880                 mutex_unlock(&table_lock);
 881                 dev_dbg(ddev, "none matched\n");
 882                 return -ENODEV;
 883         }
 884
 885         if (!try_module_get(type->driver.owner)) {
 886                 mutex_unlock(&table_lock);
 887                 dev_err(ddev, "module get failed, exiting\n");
 888                 return -EIO;
 889         }
 890         mutex_unlock(&table_lock);
 891
 892         serial = create_serial(dev, interface, type);
 893         if (!serial) {
 894                 retval = -ENOMEM;
 895                 goto err_put_module;
 896         }
 897
 898         /* if this device type has a probe function, call it */
 899         if (type->probe) {
 900                 const struct usb_device_id *id;
 901
 902                 id = get_iface_id(type, interface);
 903                 retval = type->probe(serial, id);
 904
 905                 if (retval) {
 906                         dev_dbg(ddev, "sub driver rejected device\n");
 907                         goto err_put_serial;
 908                 }
 909         }
 910
 911         /* descriptor matches, let's find the endpoints needed */
 912         epds = kzalloc(sizeof(*epds), GFP_KERNEL);
 913         if (!epds) {
 914                 retval = -ENOMEM;
 915                 goto err_put_serial;
 916         }
 917
 918         find_endpoints(serial, epds);
 919
 920         if (epds->num_bulk_in < type->num_bulk_in ||
 921                         epds->num_bulk_out < type->num_bulk_out ||
 922                         epds->num_interrupt_in < type->num_interrupt_in ||
 923                         epds->num_interrupt_out < type->num_interrupt_out) {
 924                 dev_err(ddev, "required endpoints missing\n");
 925                 retval = -ENODEV;
 926                 goto err_free_epds;
 927         }
 928
 929         if (type->calc_num_ports) {
 930                 retval = type->calc_num_ports(serial, epds);
 931                 if (retval < 0)
 932                         goto err_free_epds;
 933                 num_ports = retval;
 934         }
 935
 936         if (!num_ports)
 937                 num_ports = type->num_ports;
 938
 939         if (num_ports > MAX_NUM_PORTS) {
 940                 dev_warn(ddev, "too many ports requested: %d\n", num_ports);
 941                 num_ports = MAX_NUM_PORTS;
 942         }
 943
 944         serial->num_ports = (unsigned char)num_ports;
 945         serial->num_bulk_in = epds->num_bulk_in;
 946         serial->num_bulk_out = epds->num_bulk_out;
 947         serial->num_interrupt_in = epds->num_interrupt_in;
 948         serial->num_interrupt_out = epds->num_interrupt_out;
 949
 950         /* found all that we need */
 951         dev_info(ddev, "%s converter detected\n", type->description);
 952
 953         /* create our ports, we need as many as the max endpoints */
 954         /* we don't use num_ports here because some devices have more
 955            endpoint pairs than ports */
 956         max_endpoints = max(epds->num_bulk_in, epds->num_bulk_out);
 957         max_endpoints = max(max_endpoints, epds->num_interrupt_in);
 958         max_endpoints = max(max_endpoints, epds->num_interrupt_out);
 959         max_endpoints = max(max_endpoints, serial->num_ports);
 960         serial->num_port_pointers = max_endpoints;
 961
 962         dev_dbg(ddev, "setting up %d port structure(s)\n", max_endpoints);
 963         for (i = 0; i < max_endpoints; ++i) {
 964                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 965                 if (!port) {
 966                         retval = -ENOMEM;
 967                         goto err_free_epds;
 968                 }
 969                 tty_port_init(&port->port);
 970                 port->port.ops = &serial_port_ops;
 971                 port->serial = serial;
 972                 spin_lock_init(&port->lock);
 973                 /* Keep this for private driver use for the moment but
 974                    should probably go away */
 975                 INIT_WORK(&port->work, usb_serial_port_work);
 976                 serial->port[i] = port;
 977                 port->dev.parent = &interface->dev;
 978                 port->dev.driver = NULL;
 979                 port->dev.bus = &usb_serial_bus_type;
 980                 port->dev.release = &usb_serial_port_release;
 981                 port->dev.groups = usb_serial_port_groups;
 982                 device_initialize(&port->dev);
 983         }
 984
 985         /* set up the endpoint information */
 986         for (i = 0; i < epds->num_bulk_in; ++i) {
 987                 retval = setup_port_bulk_in(serial->port[i], epds->bulk_in[i]);
 988                 if (retval)
 989                         goto err_free_epds;
 990         }
 991
 992         for (i = 0; i < epds->num_bulk_out; ++i) {
 993                 retval = setup_port_bulk_out(serial->port[i],
 994                                 epds->bulk_out[i]);
 995                 if (retval)
 996                         goto err_free_epds;
 997         }
 998
 999         if (serial->type->read_int_callback) {
1000                 for (i = 0; i < epds->num_interrupt_in; ++i) {
1001                         retval = setup_port_interrupt_in(serial->port[i],
1002                                         epds->interrupt_in[i]);
1003                         if (retval)
1004                                 goto err_free_epds;
1005                 }
1006         } else if (epds->num_interrupt_in) {
1007                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1008         }
1009
1010         if (serial->type->write_int_callback) {
1011                 for (i = 0; i < epds->num_interrupt_out; ++i) {
1012                         retval = setup_port_interrupt_out(serial->port[i],
1013                                         epds->interrupt_out[i]);
1014                         if (retval)
1015                                 goto err_free_epds;
1016                 }
1017         } else if (epds->num_interrupt_out) {
1018                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1019         }
1020
1021         usb_set_intfdata(interface, serial);
1022
1023         /* if this device type has an attach function, call it */
1024         if (type->attach) {
1025                 retval = type->attach(serial);
1026                 if (retval < 0)
1027                         goto err_free_epds;
1028                 serial->attached = 1;
1029                 if (retval > 0) {
1030                         /* quietly accept this device, but don't bind to a
1031                            serial port as it's about to disappear */
1032                         serial->num_ports = 0;
1033                         goto exit;
1034                 }
1035         } else {
1036                 serial->attached = 1;
1037         }
1038
1039         retval = allocate_minors(serial, num_ports);
1040         if (retval) {
1041                 dev_err(ddev, "No more free serial minor numbers\n");
1042                 goto err_free_epds;
1043         }
1044
1045         /* register all of the individual ports with the driver core */
1046         for (i = 0; i < num_ports; ++i) {
1047                 port = serial->port[i];
1048                 dev_set_name(&port->dev, "ttyUSB%d", port->minor);
1049                 dev_dbg(ddev, "registering %s\n", dev_name(&port->dev));
1050                 device_enable_async_suspend(&port->dev);
1051
1052                 retval = device_add(&port->dev);
1053                 if (retval)
1054                         dev_err(ddev, "Error registering port device, continuing\n");
1055         }
1056
1057         if (num_ports > 0)
1058                 usb_serial_console_init(serial->port[0]->minor);
1059 exit:
1060         kfree(epds);
1061         module_put(type->driver.owner);
1062         return 0;
1063
1064 err_free_epds:
1065         kfree(epds);
1066 err_put_serial:
1067         usb_serial_put(serial);
1068 err_put_module:
1069         module_put(type->driver.owner);
1070
1071         return retval;
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         idr_destroy(&serial_minors);
1293 }
1294
1295
1296 module_init(usb_serial_init);
1297 module_exit(usb_serial_exit);
1298
1299 #define set_to_generic_if_null(type, function)                          \
1300         do {                                                            \
1301                 if (!type->function) {                                  \
1302                         type->function = usb_serial_generic_##function; \
1303                         pr_debug("%s: using generic " #function "\n",   \
1304                                                 type->driver.name);     \
1305                 }                                                       \
1306         } while (0)
1307
1308 static void usb_serial_operations_init(struct usb_serial_driver *device)
1309 {
1310         set_to_generic_if_null(device, open);
1311         set_to_generic_if_null(device, write);
1312         set_to_generic_if_null(device, close);
1313         set_to_generic_if_null(device, write_room);
1314         set_to_generic_if_null(device, chars_in_buffer);
1315         if (device->tx_empty)
1316                 set_to_generic_if_null(device, wait_until_sent);
1317         set_to_generic_if_null(device, read_bulk_callback);
1318         set_to_generic_if_null(device, write_bulk_callback);
1319         set_to_generic_if_null(device, process_read_urb);
1320         set_to_generic_if_null(device, prepare_write_buffer);
1321 }
1322
1323 static int usb_serial_register(struct usb_serial_driver *driver)
1324 {
1325         int retval;
1326
1327         if (usb_disabled())
1328                 return -ENODEV;
1329
1330         if (!driver->description)
1331                 driver->description = driver->driver.name;
1332         if (!driver->usb_driver) {
1333                 WARN(1, "Serial driver %s has no usb_driver\n",
1334                                 driver->description);
1335                 return -EINVAL;
1336         }
1337
1338         usb_serial_operations_init(driver);
1339
1340         /* Add this device to our list of devices */
1341         mutex_lock(&table_lock);
1342         list_add(&driver->driver_list, &usb_serial_driver_list);
1343
1344         retval = usb_serial_bus_register(driver);
1345         if (retval) {
1346                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1347                 list_del(&driver->driver_list);
1348         } else {
1349                 pr_info("USB Serial support registered for %s\n", driver->description);
1350         }
1351         mutex_unlock(&table_lock);
1352         return retval;
1353 }
1354
1355 static void usb_serial_deregister(struct usb_serial_driver *device)
1356 {
1357         pr_info("USB Serial deregistering driver %s\n", device->description);
1358
1359         mutex_lock(&table_lock);
1360         list_del(&device->driver_list);
1361         mutex_unlock(&table_lock);
1362
1363         usb_serial_bus_deregister(device);
1364 }
1365
1366 /**
1367  * usb_serial_register_drivers - register drivers for a usb-serial module
1368  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1369  * @name: name of the usb_driver for this set of @serial_drivers
1370  * @id_table: list of all devices this @serial_drivers set binds to
1371  *
1372  * Registers all the drivers in the @serial_drivers array, and dynamically
1373  * creates a struct usb_driver with the name @name and id_table of @id_table.
1374  */
1375 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1376                                 const char *name,
1377                                 const struct usb_device_id *id_table)
1378 {
1379         int rc;
1380         struct usb_driver *udriver;
1381         struct usb_serial_driver * const *sd;
1382
1383         /*
1384          * udriver must be registered before any of the serial drivers,
1385          * because the store_new_id() routine for the serial drivers (in
1386          * bus.c) probes udriver.
1387          *
1388          * Performance hack: We don't want udriver to be probed until
1389          * the serial drivers are registered, because the probe would
1390          * simply fail for lack of a matching serial driver.
1391          * So we leave udriver's id_table set to NULL until we are all set.
1392          *
1393          * Suspend/resume support is implemented in the usb-serial core,
1394          * so fill in the PM-related fields in udriver.
1395          */
1396         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1397         if (!udriver)
1398                 return -ENOMEM;
1399
1400         udriver->name = name;
1401         udriver->no_dynamic_id = 1;
1402         udriver->supports_autosuspend = 1;
1403         udriver->suspend = usb_serial_suspend;
1404         udriver->resume = usb_serial_resume;
1405         udriver->probe = usb_serial_probe;
1406         udriver->disconnect = usb_serial_disconnect;
1407
1408         /* we only set the reset_resume field if the serial_driver has one */
1409         for (sd = serial_drivers; *sd; ++sd) {
1410                 if ((*sd)->reset_resume) {
1411                         udriver->reset_resume = usb_serial_reset_resume;
1412                         break;
1413                 }
1414         }
1415
1416         rc = usb_register(udriver);
1417         if (rc)
1418                 goto failed_usb_register;
1419
1420         for (sd = serial_drivers; *sd; ++sd) {
1421                 (*sd)->usb_driver = udriver;
1422                 rc = usb_serial_register(*sd);
1423                 if (rc)
1424                         goto failed;
1425         }
1426
1427         /* Now set udriver's id_table and look for matches */
1428         udriver->id_table = id_table;
1429         rc = driver_attach(&udriver->drvwrap.driver);
1430         return 0;
1431
1432  failed:
1433         while (sd-- > serial_drivers)
1434                 usb_serial_deregister(*sd);
1435         usb_deregister(udriver);
1436 failed_usb_register:
1437         kfree(udriver);
1438         return rc;
1439 }
1440 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1441
1442 /**
1443  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1444  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1445  *
1446  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1447  * frees the struct usb_driver that was created by the call to
1448  * usb_serial_register_drivers().
1449  */
1450 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1451 {
1452         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1453
1454         for (; *serial_drivers; ++serial_drivers)
1455                 usb_serial_deregister(*serial_drivers);
1456         usb_deregister(udriver);
1457         kfree(udriver);
1458 }
1459 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1460
1461 MODULE_AUTHOR(DRIVER_AUTHOR);
1462 MODULE_DESCRIPTION(DRIVER_DESC);
1463 MODULE_LICENSE("GPL");