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_intf(serial->interface);
 155         usb_put_dev(serial->dev);
 156         kfree(serial);
 157 }
 158
 159 void usb_serial_put(struct usb_serial *serial)
 160 {
 161         kref_put(&serial->kref, destroy_serial);
 162 }
 163
 164 /*****************************************************************************
 165  * Driver tty interface functions
 166  *****************************************************************************/
 167
 168 /**
 169  * serial_install - install tty
 170  * @driver: the driver (USB in our case)
 171  * @tty: the tty being created
 172  *
 173  * Create the termios objects for this tty.  We use the default
 174  * USB serial settings but permit them to be overridden by
 175  * serial->type->init_termios.
 176  *
 177  * This is the first place a new tty gets used.  Hence this is where we
 178  * acquire references to the usb_serial structure and the driver module,
 179  * where we store a pointer to the port, and where we do an autoresume.
 180  * All these actions are reversed in serial_cleanup().
 181  */
 182 static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 183 {
 184         int idx = tty->index;
 185         struct usb_serial *serial;
 186         struct usb_serial_port *port;
 187         int retval = -ENODEV;
 188
 189         serial = usb_serial_get_by_index(idx);
 190         if (!serial)
 191                 return retval;
 192
 193         port = serial->port[idx - serial->minor];
 194         if (!port)
 195                 goto error_no_port;
 196         if (!try_module_get(serial->type->driver.owner))
 197                 goto error_module_get;
 198
 199         retval = usb_autopm_get_interface(serial->interface);
 200         if (retval)
 201                 goto error_get_interface;
 202
 203         retval = tty_port_install(&port->port, driver, tty);
 204         if (retval)
 205                 goto error_init_termios;
 206
 207         mutex_unlock(&serial->disc_mutex);
 208
 209         /* allow the driver to update the settings */
 210         if (serial->type->init_termios)
 211                 serial->type->init_termios(tty);
 212
 213         tty->driver_data = port;
 214
 215         return retval;
 216
 217  error_init_termios:
 218         usb_autopm_put_interface(serial->interface);
 219  error_get_interface:
 220         module_put(serial->type->driver.owner);
 221  error_module_get:
 222  error_no_port:
 223         usb_serial_put(serial);
 224         mutex_unlock(&serial->disc_mutex);
 225         return retval;
 226 }
 227
 228 static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
 229 {
 230         struct usb_serial_port *port =
 231                 container_of(tport, struct usb_serial_port, port);
 232         struct usb_serial *serial = port->serial;
 233         int retval;
 234
 235         mutex_lock(&serial->disc_mutex);
 236         if (serial->disconnected)
 237                 retval = -ENODEV;
 238         else
 239                 retval = port->serial->type->open(tty, port);
 240         mutex_unlock(&serial->disc_mutex);
 241
 242         if (retval < 0)
 243                 retval = usb_translate_errors(retval);
 244
 245         return retval;
 246 }
 247
 248 static int serial_open(struct tty_struct *tty, struct file *filp)
 249 {
 250         struct usb_serial_port *port = tty->driver_data;
 251
 252         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 253         return tty_port_open(&port->port, tty, filp);
 254 }
 255
 256 /**
 257  * serial_down - shut down hardware
 258  * @tport: tty port to shut down
 259  *
 260  * Shut down a USB serial port unless it is the console.  We never
 261  * shut down the console hardware as it will always be in use. Serialized
 262  * against activate by the tport mutex and kept to matching open/close pairs
 263  * of calls by the ASYNCB_INITIALIZED flag.
 264  */
 265 static void serial_down(struct tty_port *tport)
 266 {
 267         struct usb_serial_port *port =
 268                 container_of(tport, struct usb_serial_port, port);
 269         struct usb_serial_driver *drv = port->serial->type;
 270         /*
 271          * The console is magical.  Do not hang up the console hardware
 272          * or there will be tears.
 273          */
 274         if (port->port.console)
 275                 return;
 276         if (drv->close)
 277                 drv->close(port);
 278 }
 279
 280 static void serial_hangup(struct tty_struct *tty)
 281 {
 282         struct usb_serial_port *port = tty->driver_data;
 283
 284         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 285         tty_port_hangup(&port->port);
 286 }
 287
 288 static void serial_close(struct tty_struct *tty, struct file *filp)
 289 {
 290         struct usb_serial_port *port = tty->driver_data;
 291
 292         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 293         tty_port_close(&port->port, tty, filp);
 294 }
 295
 296 /**
 297  * serial_cleanup - free resources post close/hangup
 298  * @port: port to free up
 299  *
 300  * Do the resource freeing and refcount dropping for the port.
 301  * Avoid freeing the console.
 302  *
 303  * Called asynchronously after the last tty kref is dropped.
 304  */
 305 static void serial_cleanup(struct tty_struct *tty)
 306 {
 307         struct usb_serial_port *port = tty->driver_data;
 308         struct usb_serial *serial;
 309         struct module *owner;
 310
 311         /* The console is magical.  Do not hang up the console hardware
 312          * or there will be tears.
 313          */
 314         if (port->port.console)
 315                 return;
 316
 317         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 318
 319         tty->driver_data = NULL;
 320
 321         serial = port->serial;
 322         owner = serial->type->driver.owner;
 323
 324         mutex_lock(&serial->disc_mutex);
 325         if (!serial->disconnected)
 326                 usb_autopm_put_interface(serial->interface);
 327         mutex_unlock(&serial->disc_mutex);
 328
 329         usb_serial_put(serial);
 330         module_put(owner);
 331 }
 332
 333 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
 334                                                                 int count)
 335 {
 336         struct usb_serial_port *port = tty->driver_data;
 337         int retval = -ENODEV;
 338
 339         if (port->serial->dev->state == USB_STATE_NOTATTACHED)
 340                 goto exit;
 341
 342         dev_dbg(tty->dev, "%s - port %d, %d byte(s)\n", __func__,
 343                 port->number, count);
 344
 345         /* pass on to the driver specific version of this function */
 346         retval = port->serial->type->write(tty, port, buf, count);
 347         if (retval < 0)
 348                 retval = usb_translate_errors(retval);
 349 exit:
 350         return retval;
 351 }
 352
 353 static int serial_write_room(struct tty_struct *tty)
 354 {
 355         struct usb_serial_port *port = tty->driver_data;
 356
 357         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 358         /* pass on to the driver specific version of this function */
 359         return port->serial->type->write_room(tty);
 360 }
 361
 362 static int serial_chars_in_buffer(struct tty_struct *tty)
 363 {
 364         struct usb_serial_port *port = tty->driver_data;
 365         struct usb_serial *serial = port->serial;
 366         int count = 0;
 367
 368         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 369
 370         mutex_lock(&serial->disc_mutex);
 371         /* if the device was unplugged then any remaining characters
 372            fell out of the connector ;) */
 373         if (serial->disconnected)
 374                 count = 0;
 375         else
 376                 count = serial->type->chars_in_buffer(tty);
 377         mutex_unlock(&serial->disc_mutex);
 378
 379         return count;
 380 }
 381
 382 static void serial_throttle(struct tty_struct *tty)
 383 {
 384         struct usb_serial_port *port = tty->driver_data;
 385
 386         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 387
 388         /* pass on to the driver specific version of this function */
 389         if (port->serial->type->throttle)
 390                 port->serial->type->throttle(tty);
 391 }
 392
 393 static void serial_unthrottle(struct tty_struct *tty)
 394 {
 395         struct usb_serial_port *port = tty->driver_data;
 396
 397         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 398
 399         /* pass on to the driver specific version of this function */
 400         if (port->serial->type->unthrottle)
 401                 port->serial->type->unthrottle(tty);
 402 }
 403
 404 static int serial_ioctl(struct tty_struct *tty,
 405                                         unsigned int cmd, unsigned long arg)
 406 {
 407         struct usb_serial_port *port = tty->driver_data;
 408         int retval = -ENODEV;
 409
 410         dev_dbg(tty->dev, "%s - port %d, cmd 0x%.4x\n", __func__,
 411                 port->number, cmd);
 412
 413         /* pass on to the driver specific version of this function
 414            if it is available */
 415         if (port->serial->type->ioctl) {
 416                 retval = port->serial->type->ioctl(tty, cmd, arg);
 417         } else
 418                 retval = -ENOIOCTLCMD;
 419         return retval;
 420 }
 421
 422 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 423 {
 424         struct usb_serial_port *port = tty->driver_data;
 425
 426         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 427
 428         /* pass on to the driver specific version of this function
 429            if it is available */
 430         if (port->serial->type->set_termios)
 431                 port->serial->type->set_termios(tty, port, old);
 432         else
 433                 tty_termios_copy_hw(&tty->termios, old);
 434 }
 435
 436 static int serial_break(struct tty_struct *tty, int break_state)
 437 {
 438         struct usb_serial_port *port = tty->driver_data;
 439
 440         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 441
 442         /* pass on to the driver specific version of this function
 443            if it is available */
 444         if (port->serial->type->break_ctl)
 445                 port->serial->type->break_ctl(tty, break_state);
 446         return 0;
 447 }
 448
 449 static int serial_proc_show(struct seq_file *m, void *v)
 450 {
 451         struct usb_serial *serial;
 452         int i;
 453         char tmp[40];
 454
 455         seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
 456         for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
 457                 serial = usb_serial_get_by_index(i);
 458                 if (serial == NULL)
 459                         continue;
 460
 461                 seq_printf(m, "%d:", i);
 462                 if (serial->type->driver.owner)
 463                         seq_printf(m, " module:%s",
 464                                 module_name(serial->type->driver.owner));
 465                 seq_printf(m, " name:\"%s\"",
 466                                 serial->type->description);
 467                 seq_printf(m, " vendor:%04x product:%04x",
 468                         le16_to_cpu(serial->dev->descriptor.idVendor),
 469                         le16_to_cpu(serial->dev->descriptor.idProduct));
 470                 seq_printf(m, " num_ports:%d", serial->num_ports);
 471                 seq_printf(m, " port:%d", i - serial->minor + 1);
 472                 usb_make_path(serial->dev, tmp, sizeof(tmp));
 473                 seq_printf(m, " path:%s", tmp);
 474
 475                 seq_putc(m, '\n');
 476                 usb_serial_put(serial);
 477                 mutex_unlock(&serial->disc_mutex);
 478         }
 479         return 0;
 480 }
 481
 482 static int serial_proc_open(struct inode *inode, struct file *file)
 483 {
 484         return single_open(file, serial_proc_show, NULL);
 485 }
 486
 487 static const struct file_operations serial_proc_fops = {
 488         .owner          = THIS_MODULE,
 489         .open           = serial_proc_open,
 490         .read           = seq_read,
 491         .llseek         = seq_lseek,
 492         .release        = single_release,
 493 };
 494
 495 static int serial_tiocmget(struct tty_struct *tty)
 496 {
 497         struct usb_serial_port *port = tty->driver_data;
 498
 499         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 500
 501         if (port->serial->type->tiocmget)
 502                 return port->serial->type->tiocmget(tty);
 503         return -EINVAL;
 504 }
 505
 506 static int serial_tiocmset(struct tty_struct *tty,
 507                             unsigned int set, unsigned int clear)
 508 {
 509         struct usb_serial_port *port = tty->driver_data;
 510
 511         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 512
 513         if (port->serial->type->tiocmset)
 514                 return port->serial->type->tiocmset(tty, set, clear);
 515         return -EINVAL;
 516 }
 517
 518 static int serial_get_icount(struct tty_struct *tty,
 519                                 struct serial_icounter_struct *icount)
 520 {
 521         struct usb_serial_port *port = tty->driver_data;
 522
 523         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 524
 525         if (port->serial->type->get_icount)
 526                 return port->serial->type->get_icount(tty, icount);
 527         return -EINVAL;
 528 }
 529
 530 /*
 531  * We would be calling tty_wakeup here, but unfortunately some line
 532  * disciplines have an annoying habit of calling tty->write from
 533  * the write wakeup callback (e.g. n_hdlc.c).
 534  */
 535 void usb_serial_port_softint(struct usb_serial_port *port)
 536 {
 537         schedule_work(&port->work);
 538 }
 539 EXPORT_SYMBOL_GPL(usb_serial_port_softint);
 540
 541 static void usb_serial_port_work(struct work_struct *work)
 542 {
 543         struct usb_serial_port *port =
 544                 container_of(work, struct usb_serial_port, work);
 545         struct tty_struct *tty;
 546
 547         tty = tty_port_tty_get(&port->port);
 548         if (!tty)
 549                 return;
 550
 551         dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
 552
 553         tty_wakeup(tty);
 554         tty_kref_put(tty);
 555 }
 556
 557 static void kill_traffic(struct usb_serial_port *port)
 558 {
 559         int i;
 560
 561         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 562                 usb_kill_urb(port->read_urbs[i]);
 563         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 564                 usb_kill_urb(port->write_urbs[i]);
 565         /*
 566          * This is tricky.
 567          * Some drivers submit the read_urb in the
 568          * handler for the write_urb or vice versa
 569          * this order determines the order in which
 570          * usb_kill_urb() must be used to reliably
 571          * kill the URBs. As it is unknown here,
 572          * both orders must be used in turn.
 573          * The call below is not redundant.
 574          */
 575         usb_kill_urb(port->read_urb);
 576         usb_kill_urb(port->interrupt_in_urb);
 577         usb_kill_urb(port->interrupt_out_urb);
 578 }
 579
 580 static void port_release(struct device *dev)
 581 {
 582         struct usb_serial_port *port = to_usb_serial_port(dev);
 583         int i;
 584
 585         dev_dbg(dev, "%s\n", __func__);
 586
 587         /*
 588          * Stop all the traffic before cancelling the work, so that
 589          * nobody will restart it by calling usb_serial_port_softint.
 590          */
 591         kill_traffic(port);
 592         cancel_work_sync(&port->work);
 593
 594         usb_free_urb(port->interrupt_in_urb);
 595         usb_free_urb(port->interrupt_out_urb);
 596         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 597                 usb_free_urb(port->read_urbs[i]);
 598                 kfree(port->bulk_in_buffers[i]);
 599         }
 600         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 601                 usb_free_urb(port->write_urbs[i]);
 602                 kfree(port->bulk_out_buffers[i]);
 603         }
 604         kfifo_free(&port->write_fifo);
 605         kfree(port->interrupt_in_buffer);
 606         kfree(port->interrupt_out_buffer);
 607         tty_port_destroy(&port->port);
 608         kfree(port);
 609 }
 610
 611 static struct usb_serial *create_serial(struct usb_device *dev,
 612                                         struct usb_interface *interface,
 613                                         struct usb_serial_driver *driver)
 614 {
 615         struct usb_serial *serial;
 616
 617         serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 618         if (!serial) {
 619                 dev_err(&dev->dev, "%s - out of memory\n", __func__);
 620                 return NULL;
 621         }
 622         serial->dev = usb_get_dev(dev);
 623         serial->type = driver;
 624         serial->interface = usb_get_intf(interface);
 625         kref_init(&serial->kref);
 626         mutex_init(&serial->disc_mutex);
 627         serial->minor = SERIAL_TTY_NO_MINOR;
 628
 629         return serial;
 630 }
 631
 632 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 633                                             struct usb_serial_driver *drv)
 634 {
 635         struct usb_dynid *dynid;
 636
 637         spin_lock(&drv->dynids.lock);
 638         list_for_each_entry(dynid, &drv->dynids.list, node) {
 639                 if (usb_match_one_id(intf, &dynid->id)) {
 640                         spin_unlock(&drv->dynids.lock);
 641                         return &dynid->id;
 642                 }
 643         }
 644         spin_unlock(&drv->dynids.lock);
 645         return NULL;
 646 }
 647
 648 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 649                                                 struct usb_interface *intf)
 650 {
 651         const struct usb_device_id *id;
 652
 653         id = usb_match_id(intf, drv->id_table);
 654         if (id) {
 655                 dev_dbg(&intf->dev, "static descriptor matches\n");
 656                 goto exit;
 657         }
 658         id = match_dynamic_id(intf, drv);
 659         if (id)
 660                 dev_dbg(&intf->dev, "dynamic descriptor matches\n");
 661 exit:
 662         return id;
 663 }
 664
 665 /* Caller must hold table_lock */
 666 static struct usb_serial_driver *search_serial_device(
 667                                         struct usb_interface *iface)
 668 {
 669         const struct usb_device_id *id = NULL;
 670         struct usb_serial_driver *drv;
 671         struct usb_driver *driver = to_usb_driver(iface->dev.driver);
 672
 673         /* Check if the usb id matches a known device */
 674         list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 675                 if (drv->usb_driver == driver)
 676                         id = get_iface_id(drv, iface);
 677                 if (id)
 678                         return drv;
 679         }
 680
 681         return NULL;
 682 }
 683
 684 static int serial_carrier_raised(struct tty_port *port)
 685 {
 686         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 687         struct usb_serial_driver *drv = p->serial->type;
 688
 689         if (drv->carrier_raised)
 690                 return drv->carrier_raised(p);
 691         /* No carrier control - don't block */
 692         return 1;
 693 }
 694
 695 static void serial_dtr_rts(struct tty_port *port, int on)
 696 {
 697         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 698         struct usb_serial *serial = p->serial;
 699         struct usb_serial_driver *drv = serial->type;
 700
 701         if (!drv->dtr_rts)
 702                 return;
 703         /*
 704          * Work-around bug in the tty-layer which can result in dtr_rts
 705          * being called after a disconnect (and tty_unregister_device
 706          * has returned). Remove once bug has been squashed.
 707          */
 708         mutex_lock(&serial->disc_mutex);
 709         if (!serial->disconnected)
 710                 drv->dtr_rts(p, on);
 711         mutex_unlock(&serial->disc_mutex);
 712 }
 713
 714 static const struct tty_port_operations serial_port_ops = {
 715         .carrier_raised = serial_carrier_raised,
 716         .dtr_rts = serial_dtr_rts,
 717         .activate = serial_activate,
 718         .shutdown = serial_down,
 719 };
 720
 721 static int usb_serial_probe(struct usb_interface *interface,
 722                                const struct usb_device_id *id)
 723 {
 724         struct device *ddev = &interface->dev;
 725         struct usb_device *dev = interface_to_usbdev(interface);
 726         struct usb_serial *serial = NULL;
 727         struct usb_serial_port *port;
 728         struct usb_host_interface *iface_desc;
 729         struct usb_endpoint_descriptor *endpoint;
 730         struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
 731         struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
 732         struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
 733         struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 734         struct usb_serial_driver *type = NULL;
 735         int retval;
 736         unsigned int minor;
 737         int buffer_size;
 738         int i;
 739         int j;
 740         int num_interrupt_in = 0;
 741         int num_interrupt_out = 0;
 742         int num_bulk_in = 0;
 743         int num_bulk_out = 0;
 744         int num_ports = 0;
 745         int max_endpoints;
 746
 747         mutex_lock(&table_lock);
 748         type = search_serial_device(interface);
 749         if (!type) {
 750                 mutex_unlock(&table_lock);
 751                 dev_dbg(ddev, "none matched\n");
 752                 return -ENODEV;
 753         }
 754
 755         if (!try_module_get(type->driver.owner)) {
 756                 mutex_unlock(&table_lock);
 757                 dev_err(ddev, "module get failed, exiting\n");
 758                 return -EIO;
 759         }
 760         mutex_unlock(&table_lock);
 761
 762         serial = create_serial(dev, interface, type);
 763         if (!serial) {
 764                 module_put(type->driver.owner);
 765                 dev_err(ddev, "%s - out of memory\n", __func__);
 766                 return -ENOMEM;
 767         }
 768
 769         /* if this device type has a probe function, call it */
 770         if (type->probe) {
 771                 const struct usb_device_id *id;
 772
 773                 id = get_iface_id(type, interface);
 774                 retval = type->probe(serial, id);
 775
 776                 if (retval) {
 777                         dev_dbg(ddev, "sub driver rejected device\n");
 778                         usb_serial_put(serial);
 779                         module_put(type->driver.owner);
 780                         return retval;
 781                 }
 782         }
 783
 784         /* descriptor matches, let's find the endpoints needed */
 785         /* check out the endpoints */
 786         iface_desc = interface->cur_altsetting;
 787         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 788                 endpoint = &iface_desc->endpoint[i].desc;
 789
 790                 if (usb_endpoint_is_bulk_in(endpoint)) {
 791                         /* we found a bulk in endpoint */
 792                         dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
 793                         bulk_in_endpoint[num_bulk_in] = endpoint;
 794                         ++num_bulk_in;
 795                 }
 796
 797                 if (usb_endpoint_is_bulk_out(endpoint)) {
 798                         /* we found a bulk out endpoint */
 799                         dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
 800                         bulk_out_endpoint[num_bulk_out] = endpoint;
 801                         ++num_bulk_out;
 802                 }
 803
 804                 if (usb_endpoint_is_int_in(endpoint)) {
 805                         /* we found a interrupt in endpoint */
 806                         dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
 807                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 808                         ++num_interrupt_in;
 809                 }
 810
 811                 if (usb_endpoint_is_int_out(endpoint)) {
 812                         /* we found an interrupt out endpoint */
 813                         dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
 814                         interrupt_out_endpoint[num_interrupt_out] = endpoint;
 815                         ++num_interrupt_out;
 816                 }
 817         }
 818
 819 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 820         /* BEGIN HORRIBLE HACK FOR PL2303 */
 821         /* this is needed due to the looney way its endpoints are set up */
 822         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 823              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 824             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 825              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 826             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 827              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 828             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 829              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 830                 if (interface != dev->actconfig->interface[0]) {
 831                         /* check out the endpoints of the other interface*/
 832                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 833                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 834                                 endpoint = &iface_desc->endpoint[i].desc;
 835                                 if (usb_endpoint_is_int_in(endpoint)) {
 836                                         /* we found a interrupt in endpoint */
 837                                         dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
 838                                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 839                                         ++num_interrupt_in;
 840                                 }
 841                         }
 842                 }
 843
 844                 /* Now make sure the PL-2303 is configured correctly.
 845                  * If not, give up now and hope this hack will work
 846                  * properly during a later invocation of usb_serial_probe
 847                  */
 848                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 849                         dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 850                         usb_serial_put(serial);
 851                         module_put(type->driver.owner);
 852                         return -ENODEV;
 853                 }
 854         }
 855         /* END HORRIBLE HACK FOR PL2303 */
 856 #endif
 857
 858 #ifdef CONFIG_USB_SERIAL_GENERIC
 859         if (type == &usb_serial_generic_device) {
 860                 num_ports = num_bulk_out;
 861                 if (num_ports == 0) {
 862                         dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
 863                         usb_serial_put(serial);
 864                         module_put(type->driver.owner);
 865                         return -EIO;
 866                 }
 867                 dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
 868                 dev_info(ddev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n");
 869         }
 870 #endif
 871         if (!num_ports) {
 872                 /* if this device type has a calc_num_ports function, call it */
 873                 if (type->calc_num_ports)
 874                         num_ports = type->calc_num_ports(serial);
 875                 if (!num_ports)
 876                         num_ports = type->num_ports;
 877         }
 878
 879         serial->num_ports = num_ports;
 880         serial->num_bulk_in = num_bulk_in;
 881         serial->num_bulk_out = num_bulk_out;
 882         serial->num_interrupt_in = num_interrupt_in;
 883         serial->num_interrupt_out = num_interrupt_out;
 884
 885         /* found all that we need */
 886         dev_info(ddev, "%s converter detected\n", type->description);
 887
 888         /* create our ports, we need as many as the max endpoints */
 889         /* we don't use num_ports here because some devices have more
 890            endpoint pairs than ports */
 891         max_endpoints = max(num_bulk_in, num_bulk_out);
 892         max_endpoints = max(max_endpoints, num_interrupt_in);
 893         max_endpoints = max(max_endpoints, num_interrupt_out);
 894         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 895         serial->num_port_pointers = max_endpoints;
 896
 897         dev_dbg(ddev, "setting up %d port structures for this device", max_endpoints);
 898         for (i = 0; i < max_endpoints; ++i) {
 899                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 900                 if (!port)
 901                         goto probe_error;
 902                 tty_port_init(&port->port);
 903                 port->port.ops = &serial_port_ops;
 904                 port->serial = serial;
 905                 spin_lock_init(&port->lock);
 906                 /* Keep this for private driver use for the moment but
 907                    should probably go away */
 908                 INIT_WORK(&port->work, usb_serial_port_work);
 909                 serial->port[i] = port;
 910                 port->dev.parent = &interface->dev;
 911                 port->dev.driver = NULL;
 912                 port->dev.bus = &usb_serial_bus_type;
 913                 port->dev.release = &port_release;
 914                 device_initialize(&port->dev);
 915         }
 916
 917         /* set up the endpoint information */
 918         for (i = 0; i < num_bulk_in; ++i) {
 919                 endpoint = bulk_in_endpoint[i];
 920                 port = serial->port[i];
 921                 buffer_size = max_t(int, serial->type->bulk_in_size,
 922                                 usb_endpoint_maxp(endpoint));
 923                 port->bulk_in_size = buffer_size;
 924                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 925
 926                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 927                         set_bit(j, &port->read_urbs_free);
 928                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 929                         if (!port->read_urbs[j]) {
 930                                 dev_err(ddev, "No free urbs available\n");
 931                                 goto probe_error;
 932                         }
 933                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 934                                                                 GFP_KERNEL);
 935                         if (!port->bulk_in_buffers[j]) {
 936                                 dev_err(ddev, "Couldn't allocate bulk_in_buffer\n");
 937                                 goto probe_error;
 938                         }
 939                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 940                                         usb_rcvbulkpipe(dev,
 941                                                 endpoint->bEndpointAddress),
 942                                         port->bulk_in_buffers[j], buffer_size,
 943                                         serial->type->read_bulk_callback,
 944                                         port);
 945                 }
 946
 947                 port->read_urb = port->read_urbs[0];
 948                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 949         }
 950
 951         for (i = 0; i < num_bulk_out; ++i) {
 952                 endpoint = bulk_out_endpoint[i];
 953                 port = serial->port[i];
 954                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 955                         goto probe_error;
 956                 buffer_size = serial->type->bulk_out_size;
 957                 if (!buffer_size)
 958                         buffer_size = usb_endpoint_maxp(endpoint);
 959                 port->bulk_out_size = buffer_size;
 960                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 961
 962                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 963                         set_bit(j, &port->write_urbs_free);
 964                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 965                         if (!port->write_urbs[j]) {
 966                                 dev_err(ddev, "No free urbs available\n");
 967                                 goto probe_error;
 968                         }
 969                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 970                                                                 GFP_KERNEL);
 971                         if (!port->bulk_out_buffers[j]) {
 972                                 dev_err(ddev, "Couldn't allocate bulk_out_buffer\n");
 973                                 goto probe_error;
 974                         }
 975                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 976                                         usb_sndbulkpipe(dev,
 977                                                 endpoint->bEndpointAddress),
 978                                         port->bulk_out_buffers[j], buffer_size,
 979                                         serial->type->write_bulk_callback,
 980                                         port);
 981                 }
 982
 983                 port->write_urb = port->write_urbs[0];
 984                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 985         }
 986
 987         if (serial->type->read_int_callback) {
 988                 for (i = 0; i < num_interrupt_in; ++i) {
 989                         endpoint = interrupt_in_endpoint[i];
 990                         port = serial->port[i];
 991                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 992                         if (!port->interrupt_in_urb) {
 993                                 dev_err(ddev, "No free urbs available\n");
 994                                 goto probe_error;
 995                         }
 996                         buffer_size = usb_endpoint_maxp(endpoint);
 997                         port->interrupt_in_endpointAddress =
 998                                                 endpoint->bEndpointAddress;
 999                         port->interrupt_in_buffer = kmalloc(buffer_size,
1000                                                                 GFP_KERNEL);
1001                         if (!port->interrupt_in_buffer) {
1002                                 dev_err(ddev, "Couldn't allocate interrupt_in_buffer\n");
1003                                 goto probe_error;
1004                         }
1005                         usb_fill_int_urb(port->interrupt_in_urb, dev,
1006                                 usb_rcvintpipe(dev,
1007                                                 endpoint->bEndpointAddress),
1008                                 port->interrupt_in_buffer, buffer_size,
1009                                 serial->type->read_int_callback, port,
1010                                 endpoint->bInterval);
1011                 }
1012         } else if (num_interrupt_in) {
1013                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1014         }
1015
1016         if (serial->type->write_int_callback) {
1017                 for (i = 0; i < num_interrupt_out; ++i) {
1018                         endpoint = interrupt_out_endpoint[i];
1019                         port = serial->port[i];
1020                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1021                         if (!port->interrupt_out_urb) {
1022                                 dev_err(ddev, "No free urbs available\n");
1023                                 goto probe_error;
1024                         }
1025                         buffer_size = usb_endpoint_maxp(endpoint);
1026                         port->interrupt_out_size = buffer_size;
1027                         port->interrupt_out_endpointAddress =
1028                                                 endpoint->bEndpointAddress;
1029                         port->interrupt_out_buffer = kmalloc(buffer_size,
1030                                                                 GFP_KERNEL);
1031                         if (!port->interrupt_out_buffer) {
1032                                 dev_err(ddev, "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                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1044         }
1045
1046         usb_set_intfdata(interface, serial);
1047
1048         /* if this device type has an attach function, call it */
1049         if (type->attach) {
1050                 retval = type->attach(serial);
1051                 if (retval < 0)
1052                         goto probe_error;
1053                 serial->attached = 1;
1054                 if (retval > 0) {
1055                         /* quietly accept this device, but don't bind to a
1056                            serial port as it's about to disappear */
1057                         serial->num_ports = 0;
1058                         goto exit;
1059                 }
1060         } else {
1061                 serial->attached = 1;
1062         }
1063
1064         /* Avoid race with tty_open and serial_install by setting the
1065          * disconnected flag and not clearing it until all ports have been
1066          * registered.
1067          */
1068         serial->disconnected = 1;
1069
1070         if (get_free_serial(serial, num_ports, &minor) == NULL) {
1071                 dev_err(ddev, "No more free serial devices\n");
1072                 goto probe_error;
1073         }
1074         serial->minor = minor;
1075
1076         /* register all of the individual ports with the driver core */
1077         for (i = 0; i < num_ports; ++i) {
1078                 port = serial->port[i];
1079                 dev_set_name(&port->dev, "ttyUSB%d", port->number);
1080                 dev_dbg(ddev, "registering %s", dev_name(&port->dev));
1081                 device_enable_async_suspend(&port->dev);
1082
1083                 retval = device_add(&port->dev);
1084                 if (retval)
1085                         dev_err(ddev, "Error registering port device, continuing\n");
1086         }
1087
1088         serial->disconnected = 0;
1089
1090         usb_serial_console_init(minor);
1091 exit:
1092         module_put(type->driver.owner);
1093         return 0;
1094
1095 probe_error:
1096         usb_serial_put(serial);
1097         module_put(type->driver.owner);
1098         return -EIO;
1099 }
1100
1101 static 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
1110         mutex_lock(&serial->disc_mutex);
1111         /* must set a flag, to signal subdrivers */
1112         serial->disconnected = 1;
1113         mutex_unlock(&serial->disc_mutex);
1114
1115         for (i = 0; i < serial->num_ports; ++i) {
1116                 port = serial->port[i];
1117                 if (port) {
1118                         struct tty_struct *tty = tty_port_tty_get(&port->port);
1119                         if (tty) {
1120                                 tty_vhangup(tty);
1121                                 tty_kref_put(tty);
1122                         }
1123                         kill_traffic(port);
1124                         cancel_work_sync(&port->work);
1125                         if (device_is_registered(&port->dev))
1126                                 device_del(&port->dev);
1127                 }
1128         }
1129         serial->type->disconnect(serial);
1130
1131         /* let the last holder of this object cause it to be cleaned up */
1132         usb_serial_put(serial);
1133         dev_info(dev, "device disconnected\n");
1134 }
1135
1136 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1137 {
1138         struct usb_serial *serial = usb_get_intfdata(intf);
1139         struct usb_serial_port *port;
1140         int i, r = 0;
1141
1142         serial->suspending = 1;
1143
1144         if (serial->type->suspend) {
1145                 r = serial->type->suspend(serial, message);
1146                 if (r < 0) {
1147                         serial->suspending = 0;
1148                         goto err_out;
1149                 }
1150         }
1151
1152         for (i = 0; i < serial->num_ports; ++i) {
1153                 port = serial->port[i];
1154                 if (port)
1155                         kill_traffic(port);
1156         }
1157
1158 err_out:
1159         return r;
1160 }
1161 EXPORT_SYMBOL(usb_serial_suspend);
1162
1163 int usb_serial_resume(struct usb_interface *intf)
1164 {
1165         struct usb_serial *serial = usb_get_intfdata(intf);
1166         int rv;
1167
1168         serial->suspending = 0;
1169         if (serial->type->resume)
1170                 rv = serial->type->resume(serial);
1171         else
1172                 rv = usb_serial_generic_resume(serial);
1173
1174         return rv;
1175 }
1176 EXPORT_SYMBOL(usb_serial_resume);
1177
1178 static int usb_serial_reset_resume(struct usb_interface *intf)
1179 {
1180         struct usb_serial *serial = usb_get_intfdata(intf);
1181         int rv;
1182
1183         serial->suspending = 0;
1184         if (serial->type->reset_resume)
1185                 rv = serial->type->reset_resume(serial);
1186         else {
1187                 rv = -EOPNOTSUPP;
1188                 intf->needs_binding = 1;
1189         }
1190
1191         return rv;
1192 }
1193
1194 static const struct tty_operations serial_ops = {
1195         .open =                 serial_open,
1196         .close =                serial_close,
1197         .write =                serial_write,
1198         .hangup =               serial_hangup,
1199         .write_room =           serial_write_room,
1200         .ioctl =                serial_ioctl,
1201         .set_termios =          serial_set_termios,
1202         .throttle =             serial_throttle,
1203         .unthrottle =           serial_unthrottle,
1204         .break_ctl =            serial_break,
1205         .chars_in_buffer =      serial_chars_in_buffer,
1206         .tiocmget =             serial_tiocmget,
1207         .tiocmset =             serial_tiocmset,
1208         .get_icount =           serial_get_icount,
1209         .cleanup =              serial_cleanup,
1210         .install =              serial_install,
1211         .proc_fops =            &serial_proc_fops,
1212 };
1213
1214
1215 struct tty_driver *usb_serial_tty_driver;
1216
1217 /* Driver structure we register with the USB core */
1218 static struct usb_driver usb_serial_driver = {
1219         .name =         "usbserial",
1220         .probe =        usb_serial_probe,
1221         .disconnect =   usb_serial_disconnect,
1222         .suspend =      usb_serial_suspend,
1223         .resume =       usb_serial_resume,
1224         .no_dynamic_id =        1,
1225         .supports_autosuspend = 1,
1226 };
1227
1228 static int __init usb_serial_init(void)
1229 {
1230         int i;
1231         int result;
1232
1233         usb_serial_tty_driver = alloc_tty_driver(SERIAL_TTY_MINORS);
1234         if (!usb_serial_tty_driver)
1235                 return -ENOMEM;
1236
1237         /* Initialize our global data */
1238         for (i = 0; i < SERIAL_TTY_MINORS; ++i)
1239                 serial_table[i] = NULL;
1240
1241         result = bus_register(&usb_serial_bus_type);
1242         if (result) {
1243                 pr_err("%s - registering bus driver failed\n", __func__);
1244                 goto exit_bus;
1245         }
1246
1247         usb_serial_tty_driver->driver_name = "usbserial";
1248         usb_serial_tty_driver->name = "ttyUSB";
1249         usb_serial_tty_driver->major = SERIAL_TTY_MAJOR;
1250         usb_serial_tty_driver->minor_start = 0;
1251         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1252         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1253         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1254                                                 TTY_DRIVER_DYNAMIC_DEV;
1255         usb_serial_tty_driver->init_termios = tty_std_termios;
1256         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1257                                                         | HUPCL | CLOCAL;
1258         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1259         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1260         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1261         result = tty_register_driver(usb_serial_tty_driver);
1262         if (result) {
1263                 pr_err("%s - tty_register_driver failed\n", __func__);
1264                 goto exit_reg_driver;
1265         }
1266
1267         /* register the USB driver */
1268         result = usb_register(&usb_serial_driver);
1269         if (result < 0) {
1270                 pr_err("%s - usb_register failed\n", __func__);
1271                 goto exit_tty;
1272         }
1273
1274         /* register the generic driver, if we should */
1275         result = usb_serial_generic_register();
1276         if (result < 0) {
1277                 pr_err("%s - registering generic driver failed\n", __func__);
1278                 goto exit_generic;
1279         }
1280
1281         return result;
1282
1283 exit_generic:
1284         usb_deregister(&usb_serial_driver);
1285
1286 exit_tty:
1287         tty_unregister_driver(usb_serial_tty_driver);
1288
1289 exit_reg_driver:
1290         bus_unregister(&usb_serial_bus_type);
1291
1292 exit_bus:
1293         pr_err("%s - returning with error %d\n", __func__, result);
1294         put_tty_driver(usb_serial_tty_driver);
1295         return result;
1296 }
1297
1298
1299 static void __exit usb_serial_exit(void)
1300 {
1301         usb_serial_console_exit();
1302
1303         usb_serial_generic_deregister();
1304
1305         usb_deregister(&usb_serial_driver);
1306         tty_unregister_driver(usb_serial_tty_driver);
1307         put_tty_driver(usb_serial_tty_driver);
1308         bus_unregister(&usb_serial_bus_type);
1309 }
1310
1311
1312 module_init(usb_serial_init);
1313 module_exit(usb_serial_exit);
1314
1315 #define set_to_generic_if_null(type, function)                          \
1316         do {                                                            \
1317                 if (!type->function) {                                  \
1318                         type->function = usb_serial_generic_##function; \
1319                         pr_debug("Had to override the " #function       \
1320                                 " usb serial operation with the generic one.");\
1321                         }                                               \
1322         } while (0)
1323
1324 static void fixup_generic(struct usb_serial_driver *device)
1325 {
1326         set_to_generic_if_null(device, open);
1327         set_to_generic_if_null(device, write);
1328         set_to_generic_if_null(device, close);
1329         set_to_generic_if_null(device, write_room);
1330         set_to_generic_if_null(device, chars_in_buffer);
1331         set_to_generic_if_null(device, read_bulk_callback);
1332         set_to_generic_if_null(device, write_bulk_callback);
1333         set_to_generic_if_null(device, disconnect);
1334         set_to_generic_if_null(device, release);
1335         set_to_generic_if_null(device, process_read_urb);
1336         set_to_generic_if_null(device, prepare_write_buffer);
1337 }
1338
1339 static int usb_serial_register(struct usb_serial_driver *driver)
1340 {
1341         int retval;
1342
1343         if (usb_disabled())
1344                 return -ENODEV;
1345
1346         fixup_generic(driver);
1347
1348         if (!driver->description)
1349                 driver->description = driver->driver.name;
1350         if (!driver->usb_driver) {
1351                 WARN(1, "Serial driver %s has no usb_driver\n",
1352                                 driver->description);
1353                 return -EINVAL;
1354         }
1355
1356         /* Add this device to our list of devices */
1357         mutex_lock(&table_lock);
1358         list_add(&driver->driver_list, &usb_serial_driver_list);
1359
1360         retval = usb_serial_bus_register(driver);
1361         if (retval) {
1362                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1363                 list_del(&driver->driver_list);
1364         } else
1365                 pr_info("USB Serial support registered for %s\n", driver->description);
1366
1367         mutex_unlock(&table_lock);
1368         return retval;
1369 }
1370
1371 static void usb_serial_deregister(struct usb_serial_driver *device)
1372 {
1373         pr_info("USB Serial deregistering driver %s\n", device->description);
1374         mutex_lock(&table_lock);
1375         list_del(&device->driver_list);
1376         usb_serial_bus_deregister(device);
1377         mutex_unlock(&table_lock);
1378 }
1379
1380 /**
1381  * usb_serial_register_drivers - register drivers for a usb-serial module
1382  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1383  * @name: name of the usb_driver for this set of @serial_drivers
1384  * @id_table: list of all devices this @serial_drivers set binds to
1385  *
1386  * Registers all the drivers in the @serial_drivers array, and dynamically
1387  * creates a struct usb_driver with the name @name and id_table of @id_table.
1388  */
1389 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1390                                 const char *name,
1391                                 const struct usb_device_id *id_table)
1392 {
1393         int rc;
1394         struct usb_driver *udriver;
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          * So we leave udriver's id_table set to NULL until we are all set.
1406          *
1407          * Suspend/resume support is implemented in the usb-serial core,
1408          * so fill in the PM-related fields in udriver.
1409          */
1410         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1411         if (!udriver)
1412                 return -ENOMEM;
1413
1414         udriver->name = name;
1415         udriver->no_dynamic_id = 1;
1416         udriver->supports_autosuspend = 1;
1417         udriver->suspend = usb_serial_suspend;
1418         udriver->resume = usb_serial_resume;
1419         udriver->probe = usb_serial_probe;
1420         udriver->disconnect = usb_serial_disconnect;
1421
1422         /* we only set the reset_resume field if the serial_driver has one */
1423         for (sd = serial_drivers; *sd; ++sd) {
1424                 if ((*sd)->reset_resume) {
1425                         udriver->reset_resume = usb_serial_reset_resume;
1426                         break;
1427                 }
1428         }
1429
1430         rc = usb_register(udriver);
1431         if (rc)
1432                 return rc;
1433
1434         for (sd = serial_drivers; *sd; ++sd) {
1435                 (*sd)->usb_driver = udriver;
1436                 rc = usb_serial_register(*sd);
1437                 if (rc)
1438                         goto failed;
1439         }
1440
1441         /* Now set udriver's id_table and look for matches */
1442         udriver->id_table = id_table;
1443         rc = driver_attach(&udriver->drvwrap.driver);
1444         return 0;
1445
1446  failed:
1447         while (sd-- > serial_drivers)
1448                 usb_serial_deregister(*sd);
1449         usb_deregister(udriver);
1450         return rc;
1451 }
1452 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1453
1454 /**
1455  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1456  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1457  *
1458  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1459  * frees the struct usb_driver that was created by the call to
1460  * usb_serial_register_drivers().
1461  */
1462 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1463 {
1464         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1465
1466         for (; *serial_drivers; ++serial_drivers)
1467                 usb_serial_deregister(*serial_drivers);
1468         usb_deregister(udriver);
1469         kfree(udriver);
1470 }
1471 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1472
1473 /* Module information */
1474 MODULE_AUTHOR(DRIVER_AUTHOR);
1475 MODULE_DESCRIPTION(DRIVER_DESC);
1476 MODULE_LICENSE("GPL");