drivers/usb/serial/usb-serial.c

   1 /*
   2  * USB Serial Converter driver
   3  *
   4  * Copyright (C) 1999 - 2005 Greg Kroah-Hartman (greg@kroah.com)
   5  * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
   6  * Copyright (C) 2000 Al Borchers (borchers@steinerpoint.com)
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License version
  10  *      2 as published by the Free Software Foundation.
  11  *
  12  * This driver was originally based on the ACM driver by Armin Fuerst (which was
  13  * based on a driver by Brad Keryan)
  14  *
  15  * See Documentation/usb/usb-serial.txt for more information on using this
  16  * driver
  17  *
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/init.h>
  23 #include <linux/slab.h>
  24 #include <linux/tty.h>
  25 #include <linux/tty_driver.h>
  26 #include <linux/tty_flip.h>
  27 #include <linux/module.h>
  28 #include <linux/moduleparam.h>
  29 #include <linux/seq_file.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/mutex.h>
  32 #include <linux/list.h>
  33 #include <linux/uaccess.h>
  34 #include <linux/serial.h>
  35 #include <linux/usb.h>
  36 #include <linux/usb/serial.h>
  37 #include <linux/kfifo.h>
  38 #include "pl2303.h"
  39
  40 /*
  41  * Version Information
  42  */
  43 #define DRIVER_AUTHOR "Greg Kroah-Hartman, greg@kroah.com, http://www.kroah.com/linux/"
  44 #define DRIVER_DESC "USB Serial Driver core"
  45
  46 /* Driver structure we register with the USB core */
  47 static struct usb_driver usb_serial_driver = {
  48         .name =         "usbserial",
  49         .probe =        usb_serial_probe,
  50         .disconnect =   usb_serial_disconnect,
  51         .suspend =      usb_serial_suspend,
  52         .resume =       usb_serial_resume,
  53         .no_dynamic_id =        1,
  54         .supports_autosuspend = 1,
  55 };
  56
  57 /* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
  58    the MODULE_DEVICE_TABLE declarations in each serial driver
  59    cause the "hotplug" program to pull in whatever module is necessary
  60    via modprobe, and modprobe will load usbserial because the serial
  61    drivers depend on it.
  62 */
  63
  64 static bool debug;
  65 /* initially all NULL */
  66 static struct usb_serial *serial_table[SERIAL_TTY_MINORS];
  67 static DEFINE_MUTEX(table_lock);
  68 static LIST_HEAD(usb_serial_driver_list);
  69
  70 /*
  71  * Look up the serial structure.  If it is found and it hasn't been
  72  * disconnected, return with its disc_mutex held and its refcount
  73  * incremented.  Otherwise return NULL.
  74  */
  75 struct usb_serial *usb_serial_get_by_index(unsigned index)
  76 {
  77         struct usb_serial *serial;
  78
  79         mutex_lock(&table_lock);
  80         serial = serial_table[index];
  81
  82         if (serial) {
  83                 mutex_lock(&serial->disc_mutex);
  84                 if (serial->disconnected) {
  85                         mutex_unlock(&serial->disc_mutex);
  86                         serial = NULL;
  87                 } else {
  88                         kref_get(&serial->kref);
  89                 }
  90         }
  91         mutex_unlock(&table_lock);
  92         return serial;
  93 }
  94
  95 static struct usb_serial *get_free_serial(struct usb_serial *serial,
  96                                         int num_ports, unsigned int *minor)
  97 {
  98         unsigned int i, j;
  99         int good_spot;
 100
 101         dbg("%s %d", __func__, num_ports);
 102
 103         *minor = 0;
 104         mutex_lock(&table_lock);
 105         for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
 106                 if (serial_table[i])
 107                         continue;
 108
 109                 good_spot = 1;
 110                 for (j = 1; j <= num_ports-1; ++j)
 111                         if ((i+j >= SERIAL_TTY_MINORS) || (serial_table[i+j])) {
 112                                 good_spot = 0;
 113                                 i += j;
 114                                 break;
 115                         }
 116                 if (good_spot == 0)
 117                         continue;
 118
 119                 *minor = i;
 120                 j = 0;
 121                 dbg("%s - minor base = %d", __func__, *minor);
 122                 for (i = *minor; (i < (*minor + num_ports)) && (i < SERIAL_TTY_MINORS); ++i) {
 123                         serial_table[i] = serial;
 124                         serial->port[j++]->number = i;
 125                 }
 126                 mutex_unlock(&table_lock);
 127                 return serial;
 128         }
 129         mutex_unlock(&table_lock);
 130         return NULL;
 131 }
 132
 133 static void return_serial(struct usb_serial *serial)
 134 {
 135         int i;
 136
 137         dbg("%s", __func__);
 138
 139         mutex_lock(&table_lock);
 140         for (i = 0; i < serial->num_ports; ++i)
 141                 serial_table[serial->minor + i] = NULL;
 142         mutex_unlock(&table_lock);
 143 }
 144
 145 static void destroy_serial(struct kref *kref)
 146 {
 147         struct usb_serial *serial;
 148         struct usb_serial_port *port;
 149         int i;
 150
 151         serial = to_usb_serial(kref);
 152
 153         dbg("%s - %s", __func__, serial->type->description);
 154
 155         /* return the minor range that this device had */
 156         if (serial->minor != SERIAL_TTY_NO_MINOR)
 157                 return_serial(serial);
 158
 159         if (serial->attached)
 160                 serial->type->release(serial);
 161
 162         /* Now that nothing is using the ports, they can be freed */
 163         for (i = 0; i < serial->num_port_pointers; ++i) {
 164                 port = serial->port[i];
 165                 if (port) {
 166                         port->serial = NULL;
 167                         put_device(&port->dev);
 168                 }
 169         }
 170
 171         usb_put_dev(serial->dev);
 172         kfree(serial);
 173 }
 174
 175 void usb_serial_put(struct usb_serial *serial)
 176 {
 177         kref_put(&serial->kref, destroy_serial);
 178 }
 179
 180 /*****************************************************************************
 181  * Driver tty interface functions
 182  *****************************************************************************/
 183
 184 /**
 185  * serial_install - install tty
 186  * @driver: the driver (USB in our case)
 187  * @tty: the tty being created
 188  *
 189  * Create the termios objects for this tty.  We use the default
 190  * USB serial settings but permit them to be overridden by
 191  * serial->type->init_termios.
 192  *
 193  * This is the first place a new tty gets used.  Hence this is where we
 194  * acquire references to the usb_serial structure and the driver module,
 195  * where we store a pointer to the port, and where we do an autoresume.
 196  * All these actions are reversed in serial_cleanup().
 197  */
 198 static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 199 {
 200         int idx = tty->index;
 201         struct usb_serial *serial;
 202         struct usb_serial_port *port;
 203         int retval = -ENODEV;
 204
 205         dbg("%s", __func__);
 206
 207         serial = usb_serial_get_by_index(idx);
 208         if (!serial)
 209                 return retval;
 210
 211         port = serial->port[idx - serial->minor];
 212         if (!port)
 213                 goto error_no_port;
 214         if (!try_module_get(serial->type->driver.owner))
 215                 goto error_module_get;
 216
 217         retval = usb_autopm_get_interface(serial->interface);
 218         if (retval)
 219                 goto error_get_interface;
 220
 221         retval = tty_standard_install(driver, tty);
 222         if (retval)
 223                 goto error_init_termios;
 224
 225         mutex_unlock(&serial->disc_mutex);
 226
 227         /* allow the driver to update the settings */
 228         if (serial->type->init_termios)
 229                 serial->type->init_termios(tty);
 230
 231         tty->driver_data = port;
 232
 233         return retval;
 234
 235  error_init_termios:
 236         usb_autopm_put_interface(serial->interface);
 237  error_get_interface:
 238         module_put(serial->type->driver.owner);
 239  error_module_get:
 240  error_no_port:
 241         usb_serial_put(serial);
 242         mutex_unlock(&serial->disc_mutex);
 243         return retval;
 244 }
 245
 246 static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
 247 {
 248         struct usb_serial_port *port =
 249                 container_of(tport, struct usb_serial_port, port);
 250         struct usb_serial *serial = port->serial;
 251         int retval;
 252
 253         mutex_lock(&serial->disc_mutex);
 254         if (serial->disconnected)
 255                 retval = -ENODEV;
 256         else
 257                 retval = port->serial->type->open(tty, port);
 258         mutex_unlock(&serial->disc_mutex);
 259
 260         if (retval < 0)
 261                 retval = usb_translate_errors(retval);
 262
 263         return retval;
 264 }
 265
 266 static int serial_open(struct tty_struct *tty, struct file *filp)
 267 {
 268         struct usb_serial_port *port = tty->driver_data;
 269
 270         dbg("%s - port %d", __func__, port->number);
 271         return tty_port_open(&port->port, tty, filp);
 272 }
 273
 274 /**
 275  * serial_down - shut down hardware
 276  * @tport: tty port to shut down
 277  *
 278  * Shut down a USB serial port unless it is the console.  We never
 279  * shut down the console hardware as it will always be in use. Serialized
 280  * against activate by the tport mutex and kept to matching open/close pairs
 281  * of calls by the ASYNCB_INITIALIZED flag.
 282  */
 283 static void serial_down(struct tty_port *tport)
 284 {
 285         struct usb_serial_port *port =
 286                 container_of(tport, struct usb_serial_port, port);
 287         struct usb_serial_driver *drv = port->serial->type;
 288         /*
 289          * The console is magical.  Do not hang up the console hardware
 290          * or there will be tears.
 291          */
 292         if (port->port.console)
 293                 return;
 294         if (drv->close)
 295                 drv->close(port);
 296 }
 297
 298 static void serial_hangup(struct tty_struct *tty)
 299 {
 300         struct usb_serial_port *port = tty->driver_data;
 301         dbg("%s - port %d", __func__, port->number);
 302         tty_port_hangup(&port->port);
 303 }
 304
 305 static void serial_close(struct tty_struct *tty, struct file *filp)
 306 {
 307         struct usb_serial_port *port = tty->driver_data;
 308         dbg("%s - port %d", __func__, port->number);
 309         tty_port_close(&port->port, tty, filp);
 310 }
 311
 312 /**
 313  * serial_cleanup - free resources post close/hangup
 314  * @port: port to free up
 315  *
 316  * Do the resource freeing and refcount dropping for the port.
 317  * Avoid freeing the console.
 318  *
 319  * Called asynchronously after the last tty kref is dropped,
 320  * and the tty layer has already done the tty_shutdown(tty);
 321  */
 322 static void serial_cleanup(struct tty_struct *tty)
 323 {
 324         struct usb_serial_port *port = tty->driver_data;
 325         struct usb_serial *serial;
 326         struct module *owner;
 327
 328         /* The console is magical.  Do not hang up the console hardware
 329          * or there will be tears.
 330          */
 331         if (port->port.console)
 332                 return;
 333
 334         dbg("%s - port %d", __func__, port->number);
 335
 336         tty->driver_data = NULL;
 337
 338         serial = port->serial;
 339         owner = serial->type->driver.owner;
 340
 341         mutex_lock(&serial->disc_mutex);
 342         if (!serial->disconnected)
 343                 usb_autopm_put_interface(serial->interface);
 344         mutex_unlock(&serial->disc_mutex);
 345
 346         usb_serial_put(serial);
 347         module_put(owner);
 348 }
 349
 350 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
 351                                                                 int count)
 352 {
 353         struct usb_serial_port *port = tty->driver_data;
 354         int retval = -ENODEV;
 355
 356         if (port->serial->dev->state == USB_STATE_NOTATTACHED)
 357                 goto exit;
 358
 359         dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
 360
 361         /* pass on to the driver specific version of this function */
 362         retval = port->serial->type->write(tty, port, buf, count);
 363         if (retval < 0)
 364                 retval = usb_translate_errors(retval);
 365 exit:
 366         return retval;
 367 }
 368
 369 static int serial_write_room(struct tty_struct *tty)
 370 {
 371         struct usb_serial_port *port = tty->driver_data;
 372         dbg("%s - port %d", __func__, port->number);
 373         /* pass on to the driver specific version of this function */
 374         return port->serial->type->write_room(tty);
 375 }
 376
 377 static int serial_chars_in_buffer(struct tty_struct *tty)
 378 {
 379         struct usb_serial_port *port = tty->driver_data;
 380         dbg("%s - port %d", __func__, port->number);
 381
 382         /* if the device was unplugged then any remaining characters
 383            fell out of the connector ;) */
 384         if (port->serial->disconnected)
 385                 return 0;
 386         /* pass on to the driver specific version of this function */
 387         return port->serial->type->chars_in_buffer(tty);
 388 }
 389
 390 static void serial_throttle(struct tty_struct *tty)
 391 {
 392         struct usb_serial_port *port = tty->driver_data;
 393         dbg("%s - port %d", __func__, port->number);
 394
 395         /* pass on to the driver specific version of this function */
 396         if (port->serial->type->throttle)
 397                 port->serial->type->throttle(tty);
 398 }
 399
 400 static void serial_unthrottle(struct tty_struct *tty)
 401 {
 402         struct usb_serial_port *port = tty->driver_data;
 403         dbg("%s - port %d", __func__, port->number);
 404
 405         /* pass on to the driver specific version of this function */
 406         if (port->serial->type->unthrottle)
 407                 port->serial->type->unthrottle(tty);
 408 }
 409
 410 static int serial_ioctl(struct tty_struct *tty,
 411                                         unsigned int cmd, unsigned long arg)
 412 {
 413         struct usb_serial_port *port = tty->driver_data;
 414         int retval = -ENODEV;
 415
 416         dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
 417
 418         /* pass on to the driver specific version of this function
 419            if it is available */
 420         if (port->serial->type->ioctl) {
 421                 retval = port->serial->type->ioctl(tty, cmd, arg);
 422         } else
 423                 retval = -ENOIOCTLCMD;
 424         return retval;
 425 }
 426
 427 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 428 {
 429         struct usb_serial_port *port = tty->driver_data;
 430         dbg("%s - port %d", __func__, port->number);
 431
 432         /* pass on to the driver specific version of this function
 433            if it is available */
 434         if (port->serial->type->set_termios)
 435                 port->serial->type->set_termios(tty, port, old);
 436         else
 437                 tty_termios_copy_hw(tty->termios, old);
 438 }
 439
 440 static int serial_break(struct tty_struct *tty, int break_state)
 441 {
 442         struct usb_serial_port *port = tty->driver_data;
 443
 444         dbg("%s - port %d", __func__, port->number);
 445
 446         /* pass on to the driver specific version of this function
 447            if it is available */
 448         if (port->serial->type->break_ctl)
 449                 port->serial->type->break_ctl(tty, break_state);
 450         return 0;
 451 }
 452
 453 static int serial_proc_show(struct seq_file *m, void *v)
 454 {
 455         struct usb_serial *serial;
 456         int i;
 457         char tmp[40];
 458
 459         dbg("%s", __func__);
 460         seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
 461         for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
 462                 serial = usb_serial_get_by_index(i);
 463                 if (serial == NULL)
 464                         continue;
 465
 466                 seq_printf(m, "%d:", i);
 467                 if (serial->type->driver.owner)
 468                         seq_printf(m, " module:%s",
 469                                 module_name(serial->type->driver.owner));
 470                 seq_printf(m, " name:\"%s\"",
 471                                 serial->type->description);
 472                 seq_printf(m, " vendor:%04x product:%04x",
 473                         le16_to_cpu(serial->dev->descriptor.idVendor),
 474                         le16_to_cpu(serial->dev->descriptor.idProduct));
 475                 seq_printf(m, " num_ports:%d", serial->num_ports);
 476                 seq_printf(m, " port:%d", i - serial->minor + 1);
 477                 usb_make_path(serial->dev, tmp, sizeof(tmp));
 478                 seq_printf(m, " path:%s", tmp);
 479
 480                 seq_putc(m, '\n');
 481                 usb_serial_put(serial);
 482                 mutex_unlock(&serial->disc_mutex);
 483         }
 484         return 0;
 485 }
 486
 487 static int serial_proc_open(struct inode *inode, struct file *file)
 488 {
 489         return single_open(file, serial_proc_show, NULL);
 490 }
 491
 492 static const struct file_operations serial_proc_fops = {
 493         .owner          = THIS_MODULE,
 494         .open           = serial_proc_open,
 495         .read           = seq_read,
 496         .llseek         = seq_lseek,
 497         .release        = single_release,
 498 };
 499
 500 static int serial_tiocmget(struct tty_struct *tty)
 501 {
 502         struct usb_serial_port *port = tty->driver_data;
 503
 504         dbg("%s - port %d", __func__, port->number);
 505
 506         if (port->serial->type->tiocmget)
 507                 return port->serial->type->tiocmget(tty);
 508         return -EINVAL;
 509 }
 510
 511 static int serial_tiocmset(struct tty_struct *tty,
 512                             unsigned int set, unsigned int clear)
 513 {
 514         struct usb_serial_port *port = tty->driver_data;
 515
 516         dbg("%s - port %d", __func__, port->number);
 517
 518         if (port->serial->type->tiocmset)
 519                 return port->serial->type->tiocmset(tty, set, clear);
 520         return -EINVAL;
 521 }
 522
 523 static int serial_get_icount(struct tty_struct *tty,
 524                                 struct serial_icounter_struct *icount)
 525 {
 526         struct usb_serial_port *port = tty->driver_data;
 527
 528         dbg("%s - port %d", __func__, port->number);
 529
 530         if (port->serial->type->get_icount)
 531                 return port->serial->type->get_icount(tty, icount);
 532         return -EINVAL;
 533 }
 534
 535 /*
 536  * We would be calling tty_wakeup here, but unfortunately some line
 537  * disciplines have an annoying habit of calling tty->write from
 538  * the write wakeup callback (e.g. n_hdlc.c).
 539  */
 540 void usb_serial_port_softint(struct usb_serial_port *port)
 541 {
 542         schedule_work(&port->work);
 543 }
 544 EXPORT_SYMBOL_GPL(usb_serial_port_softint);
 545
 546 static void usb_serial_port_work(struct work_struct *work)
 547 {
 548         struct usb_serial_port *port =
 549                 container_of(work, struct usb_serial_port, work);
 550         struct tty_struct *tty;
 551
 552         dbg("%s - port %d", __func__, port->number);
 553
 554         tty = tty_port_tty_get(&port->port);
 555         if (!tty)
 556                 return;
 557
 558         tty_wakeup(tty);
 559         tty_kref_put(tty);
 560 }
 561
 562 static void kill_traffic(struct usb_serial_port *port)
 563 {
 564         int i;
 565
 566         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 567                 usb_kill_urb(port->read_urbs[i]);
 568         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 569                 usb_kill_urb(port->write_urbs[i]);
 570         /*
 571          * This is tricky.
 572          * Some drivers submit the read_urb in the
 573          * handler for the write_urb or vice versa
 574          * this order determines the order in which
 575          * usb_kill_urb() must be used to reliably
 576          * kill the URBs. As it is unknown here,
 577          * both orders must be used in turn.
 578          * The call below is not redundant.
 579          */
 580         usb_kill_urb(port->read_urb);
 581         usb_kill_urb(port->interrupt_in_urb);
 582         usb_kill_urb(port->interrupt_out_urb);
 583 }
 584
 585 static void port_release(struct device *dev)
 586 {
 587         struct usb_serial_port *port = to_usb_serial_port(dev);
 588         int i;
 589
 590         dbg ("%s - %s", __func__, dev_name(dev));
 591
 592         /*
 593          * Stop all the traffic before cancelling the work, so that
 594          * nobody will restart it by calling usb_serial_port_softint.
 595          */
 596         kill_traffic(port);
 597         cancel_work_sync(&port->work);
 598
 599         usb_free_urb(port->interrupt_in_urb);
 600         usb_free_urb(port->interrupt_out_urb);
 601         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 602                 usb_free_urb(port->read_urbs[i]);
 603                 kfree(port->bulk_in_buffers[i]);
 604         }
 605         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 606                 usb_free_urb(port->write_urbs[i]);
 607                 kfree(port->bulk_out_buffers[i]);
 608         }
 609         kfifo_free(&port->write_fifo);
 610         kfree(port->interrupt_in_buffer);
 611         kfree(port->interrupt_out_buffer);
 612         kfree(port);
 613 }
 614
 615 static struct usb_serial *create_serial(struct usb_device *dev,
 616                                         struct usb_interface *interface,
 617                                         struct usb_serial_driver *driver)
 618 {
 619         struct usb_serial *serial;
 620
 621         serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 622         if (!serial) {
 623                 dev_err(&dev->dev, "%s - out of memory\n", __func__);
 624                 return NULL;
 625         }
 626         serial->dev = usb_get_dev(dev);
 627         serial->type = driver;
 628         serial->interface = interface;
 629         kref_init(&serial->kref);
 630         mutex_init(&serial->disc_mutex);
 631         serial->minor = SERIAL_TTY_NO_MINOR;
 632
 633         return serial;
 634 }
 635
 636 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 637                                             struct usb_serial_driver *drv)
 638 {
 639         struct usb_dynid *dynid;
 640
 641         spin_lock(&drv->dynids.lock);
 642         list_for_each_entry(dynid, &drv->dynids.list, node) {
 643                 if (usb_match_one_id(intf, &dynid->id)) {
 644                         spin_unlock(&drv->dynids.lock);
 645                         return &dynid->id;
 646                 }
 647         }
 648         spin_unlock(&drv->dynids.lock);
 649         return NULL;
 650 }
 651
 652 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 653                                                 struct usb_interface *intf)
 654 {
 655         const struct usb_device_id *id;
 656
 657         id = usb_match_id(intf, drv->id_table);
 658         if (id) {
 659                 dbg("static descriptor matches");
 660                 goto exit;
 661         }
 662         id = match_dynamic_id(intf, drv);
 663         if (id)
 664                 dbg("dynamic descriptor matches");
 665 exit:
 666         return id;
 667 }
 668
 669 /* Caller must hold table_lock */
 670 static struct usb_serial_driver *search_serial_device(
 671                                         struct usb_interface *iface)
 672 {
 673         const struct usb_device_id *id;
 674         struct usb_serial_driver *drv;
 675
 676         /* Check if the usb id matches a known device */
 677         list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 678                 id = get_iface_id(drv, iface);
 679                 if (id)
 680                         return drv;
 681         }
 682
 683         return NULL;
 684 }
 685
 686 static int serial_carrier_raised(struct tty_port *port)
 687 {
 688         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 689         struct usb_serial_driver *drv = p->serial->type;
 690
 691         if (drv->carrier_raised)
 692                 return drv->carrier_raised(p);
 693         /* No carrier control - don't block */
 694         return 1;
 695 }
 696
 697 static void serial_dtr_rts(struct tty_port *port, int on)
 698 {
 699         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 700         struct usb_serial_driver *drv = p->serial->type;
 701
 702         if (drv->dtr_rts)
 703                 drv->dtr_rts(p, on);
 704 }
 705
 706 static const struct tty_port_operations serial_port_ops = {
 707         .carrier_raised = serial_carrier_raised,
 708         .dtr_rts = serial_dtr_rts,
 709         .activate = serial_activate,
 710         .shutdown = serial_down,
 711 };
 712
 713 int usb_serial_probe(struct usb_interface *interface,
 714                                const struct usb_device_id *id)
 715 {
 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         unsigned int minor;
 728         int buffer_size;
 729         int i;
 730         int j;
 731         int num_interrupt_in = 0;
 732         int num_interrupt_out = 0;
 733         int num_bulk_in = 0;
 734         int num_bulk_out = 0;
 735         int num_ports = 0;
 736         int max_endpoints;
 737
 738         mutex_lock(&table_lock);
 739         type = search_serial_device(interface);
 740         if (!type) {
 741                 mutex_unlock(&table_lock);
 742                 dbg("none matched");
 743                 return -ENODEV;
 744         }
 745
 746         if (!try_module_get(type->driver.owner)) {
 747                 mutex_unlock(&table_lock);
 748                 dev_err(&interface->dev, "module get failed, exiting\n");
 749                 return -EIO;
 750         }
 751         mutex_unlock(&table_lock);
 752
 753         serial = create_serial(dev, interface, type);
 754         if (!serial) {
 755                 module_put(type->driver.owner);
 756                 dev_err(&interface->dev, "%s - out of memory\n", __func__);
 757                 return -ENOMEM;
 758         }
 759
 760         /* if this device type has a probe function, call it */
 761         if (type->probe) {
 762                 const struct usb_device_id *id;
 763
 764                 id = get_iface_id(type, interface);
 765                 retval = type->probe(serial, id);
 766
 767                 if (retval) {
 768                         dbg("sub driver rejected device");
 769                         kfree(serial);
 770                         module_put(type->driver.owner);
 771                         return retval;
 772                 }
 773         }
 774
 775         /* descriptor matches, let's find the endpoints needed */
 776         /* check out the endpoints */
 777         iface_desc = interface->cur_altsetting;
 778         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 779                 endpoint = &iface_desc->endpoint[i].desc;
 780
 781                 if (usb_endpoint_is_bulk_in(endpoint)) {
 782                         /* we found a bulk in endpoint */
 783                         dbg("found bulk in on endpoint %d", i);
 784                         bulk_in_endpoint[num_bulk_in] = endpoint;
 785                         ++num_bulk_in;
 786                 }
 787
 788                 if (usb_endpoint_is_bulk_out(endpoint)) {
 789                         /* we found a bulk out endpoint */
 790                         dbg("found bulk out on endpoint %d", i);
 791                         bulk_out_endpoint[num_bulk_out] = endpoint;
 792                         ++num_bulk_out;
 793                 }
 794
 795                 if (usb_endpoint_is_int_in(endpoint)) {
 796                         /* we found a interrupt in endpoint */
 797                         dbg("found interrupt in on endpoint %d", i);
 798                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 799                         ++num_interrupt_in;
 800                 }
 801
 802                 if (usb_endpoint_is_int_out(endpoint)) {
 803                         /* we found an interrupt out endpoint */
 804                         dbg("found interrupt out on endpoint %d", i);
 805                         interrupt_out_endpoint[num_interrupt_out] = endpoint;
 806                         ++num_interrupt_out;
 807                 }
 808         }
 809
 810 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 811         /* BEGIN HORRIBLE HACK FOR PL2303 */
 812         /* this is needed due to the looney way its endpoints are set up */
 813         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 814              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 815             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 816              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 817             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 818              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 819             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 820              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 821                 if (interface != dev->actconfig->interface[0]) {
 822                         /* check out the endpoints of the other interface*/
 823                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 824                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 825                                 endpoint = &iface_desc->endpoint[i].desc;
 826                                 if (usb_endpoint_is_int_in(endpoint)) {
 827                                         /* we found a interrupt in endpoint */
 828                                         dbg("found interrupt in for Prolific device on separate interface");
 829                                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 830                                         ++num_interrupt_in;
 831                                 }
 832                         }
 833                 }
 834
 835                 /* Now make sure the PL-2303 is configured correctly.
 836                  * If not, give up now and hope this hack will work
 837                  * properly during a later invocation of usb_serial_probe
 838                  */
 839                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 840                         dev_info(&interface->dev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 841                         kfree(serial);
 842                         module_put(type->driver.owner);
 843                         return -ENODEV;
 844                 }
 845         }
 846         /* END HORRIBLE HACK FOR PL2303 */
 847 #endif
 848
 849 #ifdef CONFIG_USB_SERIAL_GENERIC
 850         if (type == &usb_serial_generic_device) {
 851                 num_ports = num_bulk_out;
 852                 if (num_ports == 0) {
 853                         dev_err(&interface->dev,
 854                             "Generic device with no bulk out, not allowed.\n");
 855                         kfree(serial);
 856                         module_put(type->driver.owner);
 857                         return -EIO;
 858                 }
 859         }
 860 #endif
 861         if (!num_ports) {
 862                 /* if this device type has a calc_num_ports function, call it */
 863                 if (type->calc_num_ports)
 864                         num_ports = type->calc_num_ports(serial);
 865                 if (!num_ports)
 866                         num_ports = type->num_ports;
 867         }
 868
 869         serial->num_ports = num_ports;
 870         serial->num_bulk_in = num_bulk_in;
 871         serial->num_bulk_out = num_bulk_out;
 872         serial->num_interrupt_in = num_interrupt_in;
 873         serial->num_interrupt_out = num_interrupt_out;
 874
 875         /* found all that we need */
 876         dev_info(&interface->dev, "%s converter detected\n",
 877                         type->description);
 878
 879         /* create our ports, we need as many as the max endpoints */
 880         /* we don't use num_ports here because some devices have more
 881            endpoint pairs than ports */
 882         max_endpoints = max(num_bulk_in, num_bulk_out);
 883         max_endpoints = max(max_endpoints, num_interrupt_in);
 884         max_endpoints = max(max_endpoints, num_interrupt_out);
 885         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 886         serial->num_port_pointers = max_endpoints;
 887
 888         dbg("%s - setting up %d port structures for this device",
 889                                                 __func__, max_endpoints);
 890         for (i = 0; i < max_endpoints; ++i) {
 891                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 892                 if (!port)
 893                         goto probe_error;
 894                 tty_port_init(&port->port);
 895                 port->port.ops = &serial_port_ops;
 896                 port->serial = serial;
 897                 spin_lock_init(&port->lock);
 898                 /* Keep this for private driver use for the moment but
 899                    should probably go away */
 900                 INIT_WORK(&port->work, usb_serial_port_work);
 901                 serial->port[i] = port;
 902                 port->dev.parent = &interface->dev;
 903                 port->dev.driver = NULL;
 904                 port->dev.bus = &usb_serial_bus_type;
 905                 port->dev.release = &port_release;
 906                 device_initialize(&port->dev);
 907         }
 908
 909         /* set up the endpoint information */
 910         for (i = 0; i < num_bulk_in; ++i) {
 911                 endpoint = bulk_in_endpoint[i];
 912                 port = serial->port[i];
 913                 buffer_size = max_t(int, serial->type->bulk_in_size,
 914                                 usb_endpoint_maxp(endpoint));
 915                 port->bulk_in_size = buffer_size;
 916                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 917
 918                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 919                         set_bit(j, &port->read_urbs_free);
 920                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 921                         if (!port->read_urbs[j]) {
 922                                 dev_err(&interface->dev,
 923                                                 "No free urbs available\n");
 924                                 goto probe_error;
 925                         }
 926                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 927                                                                 GFP_KERNEL);
 928                         if (!port->bulk_in_buffers[j]) {
 929                                 dev_err(&interface->dev,
 930                                         "Couldn't allocate bulk_in_buffer\n");
 931                                 goto probe_error;
 932                         }
 933                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 934                                         usb_rcvbulkpipe(dev,
 935                                                 endpoint->bEndpointAddress),
 936                                         port->bulk_in_buffers[j], buffer_size,
 937                                         serial->type->read_bulk_callback,
 938                                         port);
 939                 }
 940
 941                 port->read_urb = port->read_urbs[0];
 942                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 943         }
 944
 945         for (i = 0; i < num_bulk_out; ++i) {
 946                 endpoint = bulk_out_endpoint[i];
 947                 port = serial->port[i];
 948                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 949                         goto probe_error;
 950                 buffer_size = serial->type->bulk_out_size;
 951                 if (!buffer_size)
 952                         buffer_size = usb_endpoint_maxp(endpoint);
 953                 port->bulk_out_size = buffer_size;
 954                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 955
 956                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 957                         set_bit(j, &port->write_urbs_free);
 958                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 959                         if (!port->write_urbs[j]) {
 960                                 dev_err(&interface->dev,
 961                                                 "No free urbs available\n");
 962                                 goto probe_error;
 963                         }
 964                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 965                                                                 GFP_KERNEL);
 966                         if (!port->bulk_out_buffers[j]) {
 967                                 dev_err(&interface->dev,
 968                                         "Couldn't allocate bulk_out_buffer\n");
 969                                 goto probe_error;
 970                         }
 971                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 972                                         usb_sndbulkpipe(dev,
 973                                                 endpoint->bEndpointAddress),
 974                                         port->bulk_out_buffers[j], buffer_size,
 975                                         serial->type->write_bulk_callback,
 976                                         port);
 977                 }
 978
 979                 port->write_urb = port->write_urbs[0];
 980                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 981         }
 982
 983         if (serial->type->read_int_callback) {
 984                 for (i = 0; i < num_interrupt_in; ++i) {
 985                         endpoint = interrupt_in_endpoint[i];
 986                         port = serial->port[i];
 987                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 988                         if (!port->interrupt_in_urb) {
 989                                 dev_err(&interface->dev,
 990                                                 "No free urbs available\n");
 991                                 goto probe_error;
 992                         }
 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                                 dev_err(&interface->dev,
1000                                     "Couldn't allocate interrupt_in_buffer\n");
1001                                 goto probe_error;
1002                         }
1003                         usb_fill_int_urb(port->interrupt_in_urb, dev,
1004                                 usb_rcvintpipe(dev,
1005                                                 endpoint->bEndpointAddress),
1006                                 port->interrupt_in_buffer, buffer_size,
1007                                 serial->type->read_int_callback, port,
1008                                 endpoint->bInterval);
1009                 }
1010         } else if (num_interrupt_in) {
1011                 dbg("the device claims to support interrupt in transfers, but read_int_callback is not defined");
1012         }
1013
1014         if (serial->type->write_int_callback) {
1015                 for (i = 0; i < num_interrupt_out; ++i) {
1016                         endpoint = interrupt_out_endpoint[i];
1017                         port = serial->port[i];
1018                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1019                         if (!port->interrupt_out_urb) {
1020                                 dev_err(&interface->dev,
1021                                                 "No free urbs available\n");
1022                                 goto probe_error;
1023                         }
1024                         buffer_size = usb_endpoint_maxp(endpoint);
1025                         port->interrupt_out_size = buffer_size;
1026                         port->interrupt_out_endpointAddress =
1027                                                 endpoint->bEndpointAddress;
1028                         port->interrupt_out_buffer = kmalloc(buffer_size,
1029                                                                 GFP_KERNEL);
1030                         if (!port->interrupt_out_buffer) {
1031                                 dev_err(&interface->dev,
1032                                   "Couldn't allocate interrupt_out_buffer\n");
1033                                 goto probe_error;
1034                         }
1035                         usb_fill_int_urb(port->interrupt_out_urb, dev,
1036                                 usb_sndintpipe(dev,
1037                                                   endpoint->bEndpointAddress),
1038                                 port->interrupt_out_buffer, buffer_size,
1039                                 serial->type->write_int_callback, port,
1040                                 endpoint->bInterval);
1041                 }
1042         } else if (num_interrupt_out) {
1043                 dbg("the device claims to support interrupt out transfers, but write_int_callback is not defined");
1044         }
1045
1046         /* if this device type has an attach function, call it */
1047         if (type->attach) {
1048                 retval = type->attach(serial);
1049                 if (retval < 0)
1050                         goto probe_error;
1051                 serial->attached = 1;
1052                 if (retval > 0) {
1053                         /* quietly accept this device, but don't bind to a
1054                            serial port as it's about to disappear */
1055                         serial->num_ports = 0;
1056                         goto exit;
1057                 }
1058         } else {
1059                 serial->attached = 1;
1060         }
1061
1062         if (get_free_serial(serial, num_ports, &minor) == NULL) {
1063                 dev_err(&interface->dev, "No more free serial devices\n");
1064                 goto probe_error;
1065         }
1066         serial->minor = minor;
1067
1068         /* register all of the individual ports with the driver core */
1069         for (i = 0; i < num_ports; ++i) {
1070                 port = serial->port[i];
1071                 dev_set_name(&port->dev, "ttyUSB%d", port->number);
1072                 dbg ("%s - registering %s", __func__, dev_name(&port->dev));
1073                 port->dev_state = PORT_REGISTERING;
1074                 device_enable_async_suspend(&port->dev);
1075
1076                 retval = device_add(&port->dev);
1077                 if (retval) {
1078                         dev_err(&port->dev, "Error registering port device, "
1079                                 "continuing\n");
1080                         port->dev_state = PORT_UNREGISTERED;
1081                 } else {
1082                         port->dev_state = PORT_REGISTERED;
1083                 }
1084         }
1085
1086         usb_serial_console_init(debug, minor);
1087
1088 exit:
1089         /* success */
1090         usb_set_intfdata(interface, serial);
1091         module_put(type->driver.owner);
1092         return 0;
1093
1094 probe_error:
1095         usb_serial_put(serial);
1096         module_put(type->driver.owner);
1097         return -EIO;
1098 }
1099 EXPORT_SYMBOL_GPL(usb_serial_probe);
1100
1101 void usb_serial_disconnect(struct usb_interface *interface)
1102 {
1103         int i;
1104         struct usb_serial *serial = usb_get_intfdata(interface);
1105         struct device *dev = &interface->dev;
1106         struct usb_serial_port *port;
1107
1108         usb_serial_console_disconnect(serial);
1109         dbg("%s", __func__);
1110
1111         mutex_lock(&serial->disc_mutex);
1112         usb_set_intfdata(interface, NULL);
1113         /* must set a flag, to signal subdrivers */
1114         serial->disconnected = 1;
1115         mutex_unlock(&serial->disc_mutex);
1116
1117         for (i = 0; i < serial->num_ports; ++i) {
1118                 port = serial->port[i];
1119                 if (port) {
1120                         struct tty_struct *tty = tty_port_tty_get(&port->port);
1121                         if (tty) {
1122                                 tty_vhangup(tty);
1123                                 tty_kref_put(tty);
1124                         }
1125                         kill_traffic(port);
1126                         cancel_work_sync(&port->work);
1127                         if (port->dev_state == PORT_REGISTERED) {
1128
1129                                 /* Make sure the port is bound so that the
1130                                  * driver's port_remove method is called.
1131                                  */
1132                                 if (!port->dev.driver) {
1133                                         int rc;
1134
1135                                         port->dev.driver =
1136                                                         &serial->type->driver;
1137                                         rc = device_bind_driver(&port->dev);
1138                                 }
1139                                 port->dev_state = PORT_UNREGISTERING;
1140                                 device_del(&port->dev);
1141                                 port->dev_state = PORT_UNREGISTERED;
1142                         }
1143                 }
1144         }
1145         serial->type->disconnect(serial);
1146
1147         /* let the last holder of this object cause it to be cleaned up */
1148         usb_serial_put(serial);
1149         dev_info(dev, "device disconnected\n");
1150 }
1151 EXPORT_SYMBOL_GPL(usb_serial_disconnect);
1152
1153 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1154 {
1155         struct usb_serial *serial = usb_get_intfdata(intf);
1156         struct usb_serial_port *port;
1157         int i, r = 0;
1158
1159         serial->suspending = 1;
1160
1161         if (serial->type->suspend) {
1162                 r = serial->type->suspend(serial, message);
1163                 if (r < 0) {
1164                         serial->suspending = 0;
1165                         goto err_out;
1166                 }
1167         }
1168
1169         for (i = 0; i < serial->num_ports; ++i) {
1170                 port = serial->port[i];
1171                 if (port)
1172                         kill_traffic(port);
1173         }
1174
1175 err_out:
1176         return r;
1177 }
1178 EXPORT_SYMBOL(usb_serial_suspend);
1179
1180 int usb_serial_resume(struct usb_interface *intf)
1181 {
1182         struct usb_serial *serial = usb_get_intfdata(intf);
1183         int rv;
1184
1185         serial->suspending = 0;
1186         if (serial->type->resume)
1187                 rv = serial->type->resume(serial);
1188         else
1189                 rv = usb_serial_generic_resume(serial);
1190
1191         return rv;
1192 }
1193 EXPORT_SYMBOL(usb_serial_resume);
1194
1195 static const struct tty_operations serial_ops = {
1196         .open =                 serial_open,
1197         .close =                serial_close,
1198         .write =                serial_write,
1199         .hangup =               serial_hangup,
1200         .write_room =           serial_write_room,
1201         .ioctl =                serial_ioctl,
1202         .set_termios =          serial_set_termios,
1203         .throttle =             serial_throttle,
1204         .unthrottle =           serial_unthrottle,
1205         .break_ctl =            serial_break,
1206         .chars_in_buffer =      serial_chars_in_buffer,
1207         .tiocmget =             serial_tiocmget,
1208         .tiocmset =             serial_tiocmset,
1209         .get_icount =           serial_get_icount,
1210         .cleanup =              serial_cleanup,
1211         .install =              serial_install,
1212         .proc_fops =            &serial_proc_fops,
1213 };
1214
1215
1216 struct tty_driver *usb_serial_tty_driver;
1217
1218 static int __init usb_serial_init(void)
1219 {
1220         int i;
1221         int result;
1222
1223         usb_serial_tty_driver = alloc_tty_driver(SERIAL_TTY_MINORS);
1224         if (!usb_serial_tty_driver)
1225                 return -ENOMEM;
1226
1227         /* Initialize our global data */
1228         for (i = 0; i < SERIAL_TTY_MINORS; ++i)
1229                 serial_table[i] = NULL;
1230
1231         result = bus_register(&usb_serial_bus_type);
1232         if (result) {
1233                 printk(KERN_ERR "usb-serial: %s - registering bus driver "
1234                        "failed\n", __func__);
1235                 goto exit_bus;
1236         }
1237
1238         usb_serial_tty_driver->driver_name = "usbserial";
1239         usb_serial_tty_driver->name = "ttyUSB";
1240         usb_serial_tty_driver->major = SERIAL_TTY_MAJOR;
1241         usb_serial_tty_driver->minor_start = 0;
1242         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1243         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1244         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1245                                                 TTY_DRIVER_DYNAMIC_DEV;
1246         usb_serial_tty_driver->init_termios = tty_std_termios;
1247         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1248                                                         | HUPCL | CLOCAL;
1249         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1250         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1251         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1252         result = tty_register_driver(usb_serial_tty_driver);
1253         if (result) {
1254                 printk(KERN_ERR "usb-serial: %s - tty_register_driver failed\n",
1255                        __func__);
1256                 goto exit_reg_driver;
1257         }
1258
1259         /* register the USB driver */
1260         result = usb_register(&usb_serial_driver);
1261         if (result < 0) {
1262                 printk(KERN_ERR "usb-serial: %s - usb_register failed\n",
1263                        __func__);
1264                 goto exit_tty;
1265         }
1266
1267         /* register the generic driver, if we should */
1268         result = usb_serial_generic_register(debug);
1269         if (result < 0) {
1270                 printk(KERN_ERR "usb-serial: %s - registering generic "
1271                        "driver failed\n", __func__);
1272                 goto exit_generic;
1273         }
1274
1275         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
1276
1277         return result;
1278
1279 exit_generic:
1280         usb_deregister(&usb_serial_driver);
1281
1282 exit_tty:
1283         tty_unregister_driver(usb_serial_tty_driver);
1284
1285 exit_reg_driver:
1286         bus_unregister(&usb_serial_bus_type);
1287
1288 exit_bus:
1289         printk(KERN_ERR "usb-serial: %s - returning with error %d\n",
1290                __func__, result);
1291         put_tty_driver(usb_serial_tty_driver);
1292         return result;
1293 }
1294
1295
1296 static void __exit usb_serial_exit(void)
1297 {
1298         usb_serial_console_exit();
1299
1300         usb_serial_generic_deregister();
1301
1302         usb_deregister(&usb_serial_driver);
1303         tty_unregister_driver(usb_serial_tty_driver);
1304         put_tty_driver(usb_serial_tty_driver);
1305         bus_unregister(&usb_serial_bus_type);
1306 }
1307
1308
1309 module_init(usb_serial_init);
1310 module_exit(usb_serial_exit);
1311
1312 #define set_to_generic_if_null(type, function)                          \
1313         do {                                                            \
1314                 if (!type->function) {                                  \
1315                         type->function = usb_serial_generic_##function; \
1316                         dbg("Had to override the " #function            \
1317                                 " usb serial operation with the generic one.");\
1318                         }                                               \
1319         } while (0)
1320
1321 static void fixup_generic(struct usb_serial_driver *device)
1322 {
1323         set_to_generic_if_null(device, open);
1324         set_to_generic_if_null(device, write);
1325         set_to_generic_if_null(device, close);
1326         set_to_generic_if_null(device, write_room);
1327         set_to_generic_if_null(device, chars_in_buffer);
1328         set_to_generic_if_null(device, read_bulk_callback);
1329         set_to_generic_if_null(device, write_bulk_callback);
1330         set_to_generic_if_null(device, disconnect);
1331         set_to_generic_if_null(device, release);
1332         set_to_generic_if_null(device, process_read_urb);
1333         set_to_generic_if_null(device, prepare_write_buffer);
1334 }
1335
1336 static int usb_serial_register(struct usb_serial_driver *driver)
1337 {
1338         int retval;
1339
1340         if (usb_disabled())
1341                 return -ENODEV;
1342
1343         fixup_generic(driver);
1344
1345         if (!driver->description)
1346                 driver->description = driver->driver.name;
1347         if (!driver->usb_driver) {
1348                 WARN(1, "Serial driver %s has no usb_driver\n",
1349                                 driver->description);
1350                 return -EINVAL;
1351         }
1352         driver->usb_driver->supports_autosuspend = 1;
1353
1354         /* Add this device to our list of devices */
1355         mutex_lock(&table_lock);
1356         list_add(&driver->driver_list, &usb_serial_driver_list);
1357
1358         retval = usb_serial_bus_register(driver);
1359         if (retval) {
1360                 printk(KERN_ERR "usb-serial: problem %d when registering "
1361                        "driver %s\n", retval, driver->description);
1362                 list_del(&driver->driver_list);
1363         } else
1364                 printk(KERN_INFO "USB Serial support registered for %s\n",
1365                                                 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         printk(KERN_INFO "USB Serial deregistering driver %s\n",
1374                device->description);
1375         mutex_lock(&table_lock);
1376         list_del(&device->driver_list);
1377         usb_serial_bus_deregister(device);
1378         mutex_unlock(&table_lock);
1379 }
1380
1381 /**
1382  * usb_serial_register_drivers - register drivers for a usb-serial module
1383  * @udriver: usb_driver used for matching devices/interfaces
1384  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1385  *
1386  * Registers @udriver and all the drivers in the @serial_drivers array.
1387  * Automatically fills in the .no_dynamic_id field in @udriver and
1388  * the .usb_driver field in each serial driver.
1389  */
1390 int usb_serial_register_drivers(struct usb_driver *udriver,
1391                 struct usb_serial_driver * const serial_drivers[])
1392 {
1393         int rc;
1394         const struct usb_device_id *saved_id_table;
1395         struct usb_serial_driver * const *sd;
1396
1397         /*
1398          * udriver must be registered before any of the serial drivers,
1399          * because the store_new_id() routine for the serial drivers (in
1400          * bus.c) probes udriver.
1401          *
1402          * Performance hack: We don't want udriver to be probed until
1403          * the serial drivers are registered, because the probe would
1404          * simply fail for lack of a matching serial driver.
1405          * Therefore save off udriver's id_table until we are all set.
1406          */
1407         saved_id_table = udriver->id_table;
1408         udriver->id_table = NULL;
1409
1410         udriver->no_dynamic_id = 1;
1411         rc = usb_register(udriver);
1412         if (rc)
1413                 return rc;
1414
1415         for (sd = serial_drivers; *sd; ++sd) {
1416                 (*sd)->usb_driver = udriver;
1417                 rc = usb_serial_register(*sd);
1418                 if (rc)
1419                         goto failed;
1420         }
1421
1422         /* Now restore udriver's id_table and look for matches */
1423         udriver->id_table = saved_id_table;
1424         rc = driver_attach(&udriver->drvwrap.driver);
1425         return 0;
1426
1427  failed:
1428         while (sd-- > serial_drivers)
1429                 usb_serial_deregister(*sd);
1430         usb_deregister(udriver);
1431         return rc;
1432 }
1433 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1434
1435 /**
1436  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1437  * @udriver: usb_driver to unregister
1438  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1439  *
1440  * Deregisters @udriver and all the drivers in the @serial_drivers array.
1441  */
1442 void usb_serial_deregister_drivers(struct usb_driver *udriver,
1443                 struct usb_serial_driver * const serial_drivers[])
1444 {
1445         for (; *serial_drivers; ++serial_drivers)
1446                 usb_serial_deregister(*serial_drivers);
1447         usb_deregister(udriver);
1448 }
1449 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1450
1451 /* Module information */
1452 MODULE_AUTHOR(DRIVER_AUTHOR);
1453 MODULE_DESCRIPTION(DRIVER_DESC);
1454 MODULE_LICENSE("GPL");
1455
1456 module_param(debug, bool, S_IRUGO | S_IWUSR);
1457 MODULE_PARM_DESC(debug, "Debug enabled or not");