kernel/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 #include "pl2303.h"
  42
  43 #define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
  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 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 int usb_serial_probe(struct usb_interface *interface,
 713                                const struct usb_device_id *id)
 714 {
 715         struct device *ddev = &interface->dev;
 716         struct usb_device *dev = interface_to_usbdev(interface);
 717         struct usb_serial *serial = NULL;
 718         struct usb_serial_port *port;
 719         struct usb_host_interface *iface_desc;
 720         struct usb_endpoint_descriptor *endpoint;
 721         struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
 722         struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
 723         struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
 724         struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 725         struct usb_serial_driver *type = NULL;
 726         int retval;
 727         int buffer_size;
 728         int i;
 729         int j;
 730         int num_interrupt_in = 0;
 731         int num_interrupt_out = 0;
 732         int num_bulk_in = 0;
 733         int num_bulk_out = 0;
 734         int num_ports = 0;
 735         int max_endpoints;
 736
 737         mutex_lock(&table_lock);
 738         type = search_serial_device(interface);
 739         if (!type) {
 740                 mutex_unlock(&table_lock);
 741                 dev_dbg(ddev, "none matched\n");
 742                 return -ENODEV;
 743         }
 744
 745         if (!try_module_get(type->driver.owner)) {
 746                 mutex_unlock(&table_lock);
 747                 dev_err(ddev, "module get failed, exiting\n");
 748                 return -EIO;
 749         }
 750         mutex_unlock(&table_lock);
 751
 752         serial = create_serial(dev, interface, type);
 753         if (!serial) {
 754                 module_put(type->driver.owner);
 755                 return -ENOMEM;
 756         }
 757
 758         /* if this device type has a probe function, call it */
 759         if (type->probe) {
 760                 const struct usb_device_id *id;
 761
 762                 id = get_iface_id(type, interface);
 763                 retval = type->probe(serial, id);
 764
 765                 if (retval) {
 766                         dev_dbg(ddev, "sub driver rejected device\n");
 767                         usb_serial_put(serial);
 768                         module_put(type->driver.owner);
 769                         return retval;
 770                 }
 771         }
 772
 773         /* descriptor matches, let's find the endpoints needed */
 774         /* check out the endpoints */
 775         iface_desc = interface->cur_altsetting;
 776         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 777                 endpoint = &iface_desc->endpoint[i].desc;
 778
 779                 if (usb_endpoint_is_bulk_in(endpoint)) {
 780                         /* we found a bulk in endpoint */
 781                         dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
 782                         if (num_bulk_in < MAX_NUM_PORTS) {
 783                                 bulk_in_endpoint[num_bulk_in] = endpoint;
 784                                 ++num_bulk_in;
 785                         }
 786                 }
 787
 788                 if (usb_endpoint_is_bulk_out(endpoint)) {
 789                         /* we found a bulk out endpoint */
 790                         dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
 791                         if (num_bulk_out < MAX_NUM_PORTS) {
 792                                 bulk_out_endpoint[num_bulk_out] = endpoint;
 793                                 ++num_bulk_out;
 794                         }
 795                 }
 796
 797                 if (usb_endpoint_is_int_in(endpoint)) {
 798                         /* we found a interrupt in endpoint */
 799                         dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
 800                         if (num_interrupt_in < MAX_NUM_PORTS) {
 801                                 interrupt_in_endpoint[num_interrupt_in] =
 802                                                 endpoint;
 803                                 ++num_interrupt_in;
 804                         }
 805                 }
 806
 807                 if (usb_endpoint_is_int_out(endpoint)) {
 808                         /* we found an interrupt out endpoint */
 809                         dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
 810                         if (num_interrupt_out < MAX_NUM_PORTS) {
 811                                 interrupt_out_endpoint[num_interrupt_out] =
 812                                                 endpoint;
 813                                 ++num_interrupt_out;
 814                         }
 815                 }
 816         }
 817
 818 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 819         /* BEGIN HORRIBLE HACK FOR PL2303 */
 820         /* this is needed due to the looney way its endpoints are set up */
 821         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 822              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 823             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 824              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 825             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 826              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 827             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 828              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 829                 if (interface != dev->actconfig->interface[0]) {
 830                         /* check out the endpoints of the other interface*/
 831                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 832                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 833                                 endpoint = &iface_desc->endpoint[i].desc;
 834                                 if (usb_endpoint_is_int_in(endpoint)) {
 835                                         /* we found a interrupt in endpoint */
 836                                         dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
 837                                         if (num_interrupt_in < MAX_NUM_PORTS) {
 838                                                 interrupt_in_endpoint[num_interrupt_in] = endpoint;
 839                                                 ++num_interrupt_in;
 840                                         }
 841                                 }
 842                         }
 843                 }
 844
 845                 /* Now make sure the PL-2303 is configured correctly.
 846                  * If not, give up now and hope this hack will work
 847                  * properly during a later invocation of usb_serial_probe
 848                  */
 849                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 850                         dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 851                         usb_serial_put(serial);
 852                         module_put(type->driver.owner);
 853                         return -ENODEV;
 854                 }
 855         }
 856         /* END HORRIBLE HACK FOR PL2303 */
 857 #endif
 858
 859 #ifdef CONFIG_USB_SERIAL_GENERIC
 860         if (type == &usb_serial_generic_device) {
 861                 num_ports = num_bulk_out;
 862                 if (num_ports == 0) {
 863                         dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
 864                         usb_serial_put(serial);
 865                         module_put(type->driver.owner);
 866                         return -EIO;
 867                 }
 868                 dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
 869                 dev_info(ddev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n");
 870         }
 871 #endif
 872         if (!num_ports) {
 873                 /* if this device type has a calc_num_ports function, call it */
 874                 if (type->calc_num_ports)
 875                         num_ports = type->calc_num_ports(serial);
 876                 if (!num_ports)
 877                         num_ports = type->num_ports;
 878         }
 879
 880         if (num_ports > MAX_NUM_PORTS) {
 881                 dev_warn(ddev, "too many ports requested: %d\n", num_ports);
 882                 num_ports = MAX_NUM_PORTS;
 883         }
 884
 885         serial->num_ports = num_ports;
 886         serial->num_bulk_in = num_bulk_in;
 887         serial->num_bulk_out = num_bulk_out;
 888         serial->num_interrupt_in = num_interrupt_in;
 889         serial->num_interrupt_out = num_interrupt_out;
 890
 891         /* found all that we need */
 892         dev_info(ddev, "%s converter detected\n", type->description);
 893
 894         /* create our ports, we need as many as the max endpoints */
 895         /* we don't use num_ports here because some devices have more
 896            endpoint pairs than ports */
 897         max_endpoints = max(num_bulk_in, num_bulk_out);
 898         max_endpoints = max(max_endpoints, num_interrupt_in);
 899         max_endpoints = max(max_endpoints, num_interrupt_out);
 900         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 901         serial->num_port_pointers = max_endpoints;
 902
 903         dev_dbg(ddev, "setting up %d port structure(s)\n", max_endpoints);
 904         for (i = 0; i < max_endpoints; ++i) {
 905                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 906                 if (!port)
 907                         goto probe_error;
 908                 tty_port_init(&port->port);
 909                 port->port.ops = &serial_port_ops;
 910                 port->serial = serial;
 911                 spin_lock_init(&port->lock);
 912                 /* Keep this for private driver use for the moment but
 913                    should probably go away */
 914                 INIT_WORK(&port->work, usb_serial_port_work);
 915                 serial->port[i] = port;
 916                 port->dev.parent = &interface->dev;
 917                 port->dev.driver = NULL;
 918                 port->dev.bus = &usb_serial_bus_type;
 919                 port->dev.release = &usb_serial_port_release;
 920                 port->dev.groups = usb_serial_port_groups;
 921                 device_initialize(&port->dev);
 922         }
 923
 924         /* set up the endpoint information */
 925         for (i = 0; i < num_bulk_in; ++i) {
 926                 endpoint = bulk_in_endpoint[i];
 927                 port = serial->port[i];
 928                 buffer_size = max_t(int, serial->type->bulk_in_size,
 929                                 usb_endpoint_maxp(endpoint));
 930                 port->bulk_in_size = buffer_size;
 931                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 932
 933                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 934                         set_bit(j, &port->read_urbs_free);
 935                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 936                         if (!port->read_urbs[j])
 937                                 goto probe_error;
 938                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 939                                                                 GFP_KERNEL);
 940                         if (!port->bulk_in_buffers[j])
 941                                 goto probe_error;
 942                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 943                                         usb_rcvbulkpipe(dev,
 944                                                 endpoint->bEndpointAddress),
 945                                         port->bulk_in_buffers[j], buffer_size,
 946                                         serial->type->read_bulk_callback,
 947                                         port);
 948                 }
 949
 950                 port->read_urb = port->read_urbs[0];
 951                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 952         }
 953
 954         for (i = 0; i < num_bulk_out; ++i) {
 955                 endpoint = bulk_out_endpoint[i];
 956                 port = serial->port[i];
 957                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 958                         goto probe_error;
 959                 buffer_size = serial->type->bulk_out_size;
 960                 if (!buffer_size)
 961                         buffer_size = usb_endpoint_maxp(endpoint);
 962                 port->bulk_out_size = buffer_size;
 963                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 964
 965                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 966                         set_bit(j, &port->write_urbs_free);
 967                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 968                         if (!port->write_urbs[j])
 969                                 goto probe_error;
 970                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 971                                                                 GFP_KERNEL);
 972                         if (!port->bulk_out_buffers[j])
 973                                 goto probe_error;
 974                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 975                                         usb_sndbulkpipe(dev,
 976                                                 endpoint->bEndpointAddress),
 977                                         port->bulk_out_buffers[j], buffer_size,
 978                                         serial->type->write_bulk_callback,
 979                                         port);
 980                 }
 981
 982                 port->write_urb = port->write_urbs[0];
 983                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 984         }
 985
 986         if (serial->type->read_int_callback) {
 987                 for (i = 0; i < num_interrupt_in; ++i) {
 988                         endpoint = interrupt_in_endpoint[i];
 989                         port = serial->port[i];
 990                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 991                         if (!port->interrupt_in_urb)
 992                                 goto probe_error;
 993                         buffer_size = usb_endpoint_maxp(endpoint);
 994                         port->interrupt_in_endpointAddress =
 995                                                 endpoint->bEndpointAddress;
 996                         port->interrupt_in_buffer = kmalloc(buffer_size,
 997                                                                 GFP_KERNEL);
 998                         if (!port->interrupt_in_buffer)
 999                                 goto probe_error;
1000                         usb_fill_int_urb(port->interrupt_in_urb, dev,
1001                                 usb_rcvintpipe(dev,
1002                                                 endpoint->bEndpointAddress),
1003                                 port->interrupt_in_buffer, buffer_size,
1004                                 serial->type->read_int_callback, port,
1005                                 endpoint->bInterval);
1006                 }
1007         } else if (num_interrupt_in) {
1008                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1009         }
1010
1011         if (serial->type->write_int_callback) {
1012                 for (i = 0; i < num_interrupt_out; ++i) {
1013                         endpoint = interrupt_out_endpoint[i];
1014                         port = serial->port[i];
1015                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1016                         if (!port->interrupt_out_urb)
1017                                 goto probe_error;
1018                         buffer_size = usb_endpoint_maxp(endpoint);
1019                         port->interrupt_out_size = buffer_size;
1020                         port->interrupt_out_endpointAddress =
1021                                                 endpoint->bEndpointAddress;
1022                         port->interrupt_out_buffer = kmalloc(buffer_size,
1023                                                                 GFP_KERNEL);
1024                         if (!port->interrupt_out_buffer)
1025                                 goto probe_error;
1026                         usb_fill_int_urb(port->interrupt_out_urb, dev,
1027                                 usb_sndintpipe(dev,
1028                                                   endpoint->bEndpointAddress),
1029                                 port->interrupt_out_buffer, buffer_size,
1030                                 serial->type->write_int_callback, port,
1031                                 endpoint->bInterval);
1032                 }
1033         } else if (num_interrupt_out) {
1034                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1035         }
1036
1037         usb_set_intfdata(interface, serial);
1038
1039         /* if this device type has an attach function, call it */
1040         if (type->attach) {
1041                 retval = type->attach(serial);
1042                 if (retval < 0)
1043                         goto probe_error;
1044                 serial->attached = 1;
1045                 if (retval > 0) {
1046                         /* quietly accept this device, but don't bind to a
1047                            serial port as it's about to disappear */
1048                         serial->num_ports = 0;
1049                         goto exit;
1050                 }
1051         } else {
1052                 serial->attached = 1;
1053         }
1054
1055         /* Avoid race with tty_open and serial_install by setting the
1056          * disconnected flag and not clearing it until all ports have been
1057          * registered.
1058          */
1059         serial->disconnected = 1;
1060
1061         if (allocate_minors(serial, num_ports)) {
1062                 dev_err(ddev, "No more free serial minor numbers\n");
1063                 goto probe_error;
1064         }
1065
1066         /* register all of the individual ports with the driver core */
1067         for (i = 0; i < num_ports; ++i) {
1068                 port = serial->port[i];
1069                 dev_set_name(&port->dev, "ttyUSB%d", port->minor);
1070                 dev_dbg(ddev, "registering %s\n", dev_name(&port->dev));
1071                 device_enable_async_suspend(&port->dev);
1072
1073                 retval = device_add(&port->dev);
1074                 if (retval)
1075                         dev_err(ddev, "Error registering port device, continuing\n");
1076         }
1077
1078         serial->disconnected = 0;
1079
1080         usb_serial_console_init(serial->port[0]->minor);
1081 exit:
1082         module_put(type->driver.owner);
1083         return 0;
1084
1085 probe_error:
1086         usb_serial_put(serial);
1087         module_put(type->driver.owner);
1088         return -EIO;
1089 }
1090
1091 static void usb_serial_disconnect(struct usb_interface *interface)
1092 {
1093         int i;
1094         struct usb_serial *serial = usb_get_intfdata(interface);
1095         struct device *dev = &interface->dev;
1096         struct usb_serial_port *port;
1097         struct tty_struct *tty;
1098
1099         usb_serial_console_disconnect(serial);
1100
1101         mutex_lock(&serial->disc_mutex);
1102         /* must set a flag, to signal subdrivers */
1103         serial->disconnected = 1;
1104         mutex_unlock(&serial->disc_mutex);
1105
1106         for (i = 0; i < serial->num_ports; ++i) {
1107                 port = serial->port[i];
1108                 tty = tty_port_tty_get(&port->port);
1109                 if (tty) {
1110                         tty_vhangup(tty);
1111                         tty_kref_put(tty);
1112                 }
1113                 usb_serial_port_poison_urbs(port);
1114                 wake_up_interruptible(&port->port.delta_msr_wait);
1115                 cancel_work_sync(&port->work);
1116                 if (device_is_registered(&port->dev))
1117                         device_del(&port->dev);
1118         }
1119         if (serial->type->disconnect)
1120                 serial->type->disconnect(serial);
1121
1122         /* let the last holder of this object cause it to be cleaned up */
1123         usb_serial_put(serial);
1124         dev_info(dev, "device disconnected\n");
1125 }
1126
1127 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1128 {
1129         struct usb_serial *serial = usb_get_intfdata(intf);
1130         int i, r = 0;
1131
1132         serial->suspending = 1;
1133
1134         /*
1135          * serial->type->suspend() MUST return 0 in system sleep context,
1136          * otherwise, the resume callback has to recover device from
1137          * previous suspend failure.
1138          */
1139         if (serial->type->suspend) {
1140                 r = serial->type->suspend(serial, message);
1141                 if (r < 0) {
1142                         serial->suspending = 0;
1143                         goto err_out;
1144                 }
1145         }
1146
1147         for (i = 0; i < serial->num_ports; ++i)
1148                 usb_serial_port_poison_urbs(serial->port[i]);
1149 err_out:
1150         return r;
1151 }
1152 EXPORT_SYMBOL(usb_serial_suspend);
1153
1154 static void usb_serial_unpoison_port_urbs(struct usb_serial *serial)
1155 {
1156         int i;
1157
1158         for (i = 0; i < serial->num_ports; ++i)
1159                 usb_serial_port_unpoison_urbs(serial->port[i]);
1160 }
1161
1162 int usb_serial_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->resume)
1171                 rv = serial->type->resume(serial);
1172         else
1173                 rv = usb_serial_generic_resume(serial);
1174
1175         return rv;
1176 }
1177 EXPORT_SYMBOL(usb_serial_resume);
1178
1179 static int usb_serial_reset_resume(struct usb_interface *intf)
1180 {
1181         struct usb_serial *serial = usb_get_intfdata(intf);
1182         int rv;
1183
1184         usb_serial_unpoison_port_urbs(serial);
1185
1186         serial->suspending = 0;
1187         if (serial->type->reset_resume) {
1188                 rv = serial->type->reset_resume(serial);
1189         } else {
1190                 rv = -EOPNOTSUPP;
1191                 intf->needs_binding = 1;
1192         }
1193
1194         return rv;
1195 }
1196
1197 static const struct tty_operations serial_ops = {
1198         .open =                 serial_open,
1199         .close =                serial_close,
1200         .write =                serial_write,
1201         .hangup =               serial_hangup,
1202         .write_room =           serial_write_room,
1203         .ioctl =                serial_ioctl,
1204         .set_termios =          serial_set_termios,
1205         .throttle =             serial_throttle,
1206         .unthrottle =           serial_unthrottle,
1207         .break_ctl =            serial_break,
1208         .chars_in_buffer =      serial_chars_in_buffer,
1209         .wait_until_sent =      serial_wait_until_sent,
1210         .tiocmget =             serial_tiocmget,
1211         .tiocmset =             serial_tiocmset,
1212         .get_icount =           serial_get_icount,
1213         .cleanup =              serial_cleanup,
1214         .install =              serial_install,
1215         .proc_fops =            &serial_proc_fops,
1216 };
1217
1218
1219 struct tty_driver *usb_serial_tty_driver;
1220
1221 /* Driver structure we register with the USB core */
1222 static struct usb_driver usb_serial_driver = {
1223         .name =         "usbserial",
1224         .probe =        usb_serial_probe,
1225         .disconnect =   usb_serial_disconnect,
1226         .suspend =      usb_serial_suspend,
1227         .resume =       usb_serial_resume,
1228         .no_dynamic_id =        1,
1229         .supports_autosuspend = 1,
1230 };
1231
1232 static int __init usb_serial_init(void)
1233 {
1234         int result;
1235
1236         usb_serial_tty_driver = alloc_tty_driver(USB_SERIAL_TTY_MINORS);
1237         if (!usb_serial_tty_driver)
1238                 return -ENOMEM;
1239
1240         /* Initialize our global data */
1241         result = bus_register(&usb_serial_bus_type);
1242         if (result) {
1243                 pr_err("%s - registering bus driver failed\n", __func__);
1244                 goto exit_bus;
1245         }
1246
1247         usb_serial_tty_driver->driver_name = "usbserial";
1248         usb_serial_tty_driver->name = "ttyUSB";
1249         usb_serial_tty_driver->major = USB_SERIAL_TTY_MAJOR;
1250         usb_serial_tty_driver->minor_start = 0;
1251         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1252         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1253         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1254                                                 TTY_DRIVER_DYNAMIC_DEV;
1255         usb_serial_tty_driver->init_termios = tty_std_termios;
1256         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1257                                                         | HUPCL | CLOCAL;
1258         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1259         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1260         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1261         result = tty_register_driver(usb_serial_tty_driver);
1262         if (result) {
1263                 pr_err("%s - tty_register_driver failed\n", __func__);
1264                 goto exit_reg_driver;
1265         }
1266
1267         /* register the USB driver */
1268         result = usb_register(&usb_serial_driver);
1269         if (result < 0) {
1270                 pr_err("%s - usb_register failed\n", __func__);
1271                 goto exit_tty;
1272         }
1273
1274         /* register the generic driver, if we should */
1275         result = usb_serial_generic_register();
1276         if (result < 0) {
1277                 pr_err("%s - registering generic driver failed\n", __func__);
1278                 goto exit_generic;
1279         }
1280
1281         return result;
1282
1283 exit_generic:
1284         usb_deregister(&usb_serial_driver);
1285
1286 exit_tty:
1287         tty_unregister_driver(usb_serial_tty_driver);
1288
1289 exit_reg_driver:
1290         bus_unregister(&usb_serial_bus_type);
1291
1292 exit_bus:
1293         pr_err("%s - returning with error %d\n", __func__, result);
1294         put_tty_driver(usb_serial_tty_driver);
1295         return result;
1296 }
1297
1298
1299 static void __exit usb_serial_exit(void)
1300 {
1301         usb_serial_console_exit();
1302
1303         usb_serial_generic_deregister();
1304
1305         usb_deregister(&usb_serial_driver);
1306         tty_unregister_driver(usb_serial_tty_driver);
1307         put_tty_driver(usb_serial_tty_driver);
1308         bus_unregister(&usb_serial_bus_type);
1309 }
1310
1311
1312 module_init(usb_serial_init);
1313 module_exit(usb_serial_exit);
1314
1315 #define set_to_generic_if_null(type, function)                          \
1316         do {                                                            \
1317                 if (!type->function) {                                  \
1318                         type->function = usb_serial_generic_##function; \
1319                         pr_debug("%s: using generic " #function "\n",   \
1320                                                 type->driver.name);     \
1321                 }                                                       \
1322         } while (0)
1323
1324 static void usb_serial_operations_init(struct usb_serial_driver *device)
1325 {
1326         set_to_generic_if_null(device, open);
1327         set_to_generic_if_null(device, write);
1328         set_to_generic_if_null(device, close);
1329         set_to_generic_if_null(device, write_room);
1330         set_to_generic_if_null(device, chars_in_buffer);
1331         if (device->tx_empty)
1332                 set_to_generic_if_null(device, wait_until_sent);
1333         set_to_generic_if_null(device, read_bulk_callback);
1334         set_to_generic_if_null(device, write_bulk_callback);
1335         set_to_generic_if_null(device, process_read_urb);
1336         set_to_generic_if_null(device, prepare_write_buffer);
1337 }
1338
1339 static int usb_serial_register(struct usb_serial_driver *driver)
1340 {
1341         int retval;
1342
1343         if (usb_disabled())
1344                 return -ENODEV;
1345
1346         if (!driver->description)
1347                 driver->description = driver->driver.name;
1348         if (!driver->usb_driver) {
1349                 WARN(1, "Serial driver %s has no usb_driver\n",
1350                                 driver->description);
1351                 return -EINVAL;
1352         }
1353
1354         usb_serial_operations_init(driver);
1355
1356         /* Add this device to our list of devices */
1357         mutex_lock(&table_lock);
1358         list_add(&driver->driver_list, &usb_serial_driver_list);
1359
1360         retval = usb_serial_bus_register(driver);
1361         if (retval) {
1362                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1363                 list_del(&driver->driver_list);
1364         } else {
1365                 pr_info("USB Serial support registered for %s\n", driver->description);
1366         }
1367         mutex_unlock(&table_lock);
1368         return retval;
1369 }
1370
1371 static void usb_serial_deregister(struct usb_serial_driver *device)
1372 {
1373         pr_info("USB Serial deregistering driver %s\n", device->description);
1374
1375         mutex_lock(&table_lock);
1376         list_del(&device->driver_list);
1377         mutex_unlock(&table_lock);
1378
1379         usb_serial_bus_deregister(device);
1380 }
1381
1382 /**
1383  * usb_serial_register_drivers - register drivers for a usb-serial module
1384  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1385  * @name: name of the usb_driver for this set of @serial_drivers
1386  * @id_table: list of all devices this @serial_drivers set binds to
1387  *
1388  * Registers all the drivers in the @serial_drivers array, and dynamically
1389  * creates a struct usb_driver with the name @name and id_table of @id_table.
1390  */
1391 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1392                                 const char *name,
1393                                 const struct usb_device_id *id_table)
1394 {
1395         int rc;
1396         struct usb_driver *udriver;
1397         struct usb_serial_driver * const *sd;
1398
1399         /*
1400          * udriver must be registered before any of the serial drivers,
1401          * because the store_new_id() routine for the serial drivers (in
1402          * bus.c) probes udriver.
1403          *
1404          * Performance hack: We don't want udriver to be probed until
1405          * the serial drivers are registered, because the probe would
1406          * simply fail for lack of a matching serial driver.
1407          * So we leave udriver's id_table set to NULL until we are all set.
1408          *
1409          * Suspend/resume support is implemented in the usb-serial core,
1410          * so fill in the PM-related fields in udriver.
1411          */
1412         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1413         if (!udriver)
1414                 return -ENOMEM;
1415
1416         udriver->name = name;
1417         udriver->no_dynamic_id = 1;
1418         udriver->supports_autosuspend = 1;
1419         udriver->suspend = usb_serial_suspend;
1420         udriver->resume = usb_serial_resume;
1421         udriver->probe = usb_serial_probe;
1422         udriver->disconnect = usb_serial_disconnect;
1423
1424         /* we only set the reset_resume field if the serial_driver has one */
1425         for (sd = serial_drivers; *sd; ++sd) {
1426                 if ((*sd)->reset_resume) {
1427                         udriver->reset_resume = usb_serial_reset_resume;
1428                         break;
1429                 }
1430         }
1431
1432         rc = usb_register(udriver);
1433         if (rc)
1434                 return rc;
1435
1436         for (sd = serial_drivers; *sd; ++sd) {
1437                 (*sd)->usb_driver = udriver;
1438                 rc = usb_serial_register(*sd);
1439                 if (rc)
1440                         goto failed;
1441         }
1442
1443         /* Now set udriver's id_table and look for matches */
1444         udriver->id_table = id_table;
1445         rc = driver_attach(&udriver->drvwrap.driver);
1446         return 0;
1447
1448  failed:
1449         while (sd-- > serial_drivers)
1450                 usb_serial_deregister(*sd);
1451         usb_deregister(udriver);
1452         return rc;
1453 }
1454 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1455
1456 /**
1457  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1458  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1459  *
1460  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1461  * frees the struct usb_driver that was created by the call to
1462  * usb_serial_register_drivers().
1463  */
1464 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1465 {
1466         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1467
1468         for (; *serial_drivers; ++serial_drivers)
1469                 usb_serial_deregister(*serial_drivers);
1470         usb_deregister(udriver);
1471         kfree(udriver);
1472 }
1473 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1474
1475 MODULE_AUTHOR(DRIVER_AUTHOR);
1476 MODULE_DESCRIPTION(DRIVER_DESC);
1477 MODULE_LICENSE("GPL");