drivers/usb/serial/usb-serial.c

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