drivers/usb/serial/usb-serial.c

   1 /*
   2  * USB Serial Converter driver
   3  *
   4  * Copyright (C) 2009 - 2013 Johan Hovold ([email protected])
   5  * Copyright (C) 1999 - 2012 Greg Kroah-Hartman ([email protected])
   6  * Copyright (C) 2000 Peter Berger ([email protected])
   7  * Copyright (C) 2000 Al Borchers ([email protected])
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License version
  11  *      2 as published by the Free Software Foundation.
  12  *
  13  * This driver was originally based on the ACM driver by Armin Fuerst (which was
  14  * based on a driver by Brad Keryan)
  15  *
  16  * See Documentation/usb/usb-serial.txt for more information on using this
  17  * driver
  18  */
  19
  20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 #include <linux/kernel.h>
  23 #include <linux/errno.h>
  24 #include <linux/init.h>
  25 #include <linux/slab.h>
  26 #include <linux/tty.h>
  27 #include <linux/tty_driver.h>
  28 #include <linux/tty_flip.h>
  29 #include <linux/module.h>
  30 #include <linux/moduleparam.h>
  31 #include <linux/seq_file.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/mutex.h>
  34 #include <linux/list.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/serial.h>
  37 #include <linux/usb.h>
  38 #include <linux/usb/serial.h>
  39 #include <linux/kfifo.h>
  40 #include <linux/idr.h>
  41 #include "pl2303.h"
  42
  43 #define DRIVER_AUTHOR "Greg Kroah-Hartman <[email protected]>"
  44 #define DRIVER_DESC "USB Serial Driver core"
  45
  46 #define USB_SERIAL_TTY_MAJOR    188
  47 #define USB_SERIAL_TTY_MINORS   512     /* should be enough for a while */
  48
  49 /* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
  50    the MODULE_DEVICE_TABLE declarations in each serial driver
  51    cause the "hotplug" program to pull in whatever module is necessary
  52    via modprobe, and modprobe will load usbserial because the serial
  53    drivers depend on it.
  54 */
  55
  56 static DEFINE_IDR(serial_minors);
  57 static DEFINE_MUTEX(table_lock);
  58 static LIST_HEAD(usb_serial_driver_list);
  59
  60 /*
  61  * Look up the serial port structure.  If it is found and it hasn't been
  62  * disconnected, return with the parent usb_serial structure's disc_mutex held
  63  * and its refcount incremented.  Otherwise return NULL.
  64  */
  65 struct usb_serial_port *usb_serial_port_get_by_minor(unsigned minor)
  66 {
  67         struct usb_serial *serial;
  68         struct usb_serial_port *port;
  69
  70         mutex_lock(&table_lock);
  71         port = idr_find(&serial_minors, minor);
  72         if (!port)
  73                 goto exit;
  74
  75         serial = port->serial;
  76         mutex_lock(&serial->disc_mutex);
  77         if (serial->disconnected) {
  78                 mutex_unlock(&serial->disc_mutex);
  79                 port = NULL;
  80         } else {
  81                 kref_get(&serial->kref);
  82         }
  83 exit:
  84         mutex_unlock(&table_lock);
  85         return port;
  86 }
  87
  88 static int allocate_minors(struct usb_serial *serial, int num_ports)
  89 {
  90         struct usb_serial_port *port;
  91         unsigned int i, j;
  92         int minor;
  93
  94         dev_dbg(&serial->interface->dev, "%s %d\n", __func__, num_ports);
  95
  96         mutex_lock(&table_lock);
  97         for (i = 0; i < num_ports; ++i) {
  98                 port = serial->port[i];
  99                 minor = idr_alloc(&serial_minors, port, 0, 0, GFP_KERNEL);
 100                 if (minor < 0)
 101                         goto error;
 102                 port->minor = minor;
 103                 port->port_number = i;
 104         }
 105         serial->minors_reserved = 1;
 106         mutex_unlock(&table_lock);
 107         return 0;
 108 error:
 109         /* unwind the already allocated minors */
 110         for (j = 0; j < i; ++j)
 111                 idr_remove(&serial_minors, serial->port[j]->minor);
 112         mutex_unlock(&table_lock);
 113         return minor;
 114 }
 115
 116 static void release_minors(struct usb_serial *serial)
 117 {
 118         int i;
 119
 120         mutex_lock(&table_lock);
 121         for (i = 0; i < serial->num_ports; ++i)
 122                 idr_remove(&serial_minors, serial->port[i]->minor);
 123         mutex_unlock(&table_lock);
 124         serial->minors_reserved = 0;
 125 }
 126
 127 static void destroy_serial(struct kref *kref)
 128 {
 129         struct usb_serial *serial;
 130         struct usb_serial_port *port;
 131         int i;
 132
 133         serial = to_usb_serial(kref);
 134
 135         /* return the minor range that this device had */
 136         if (serial->minors_reserved)
 137                 release_minors(serial);
 138
 139         if (serial->attached && serial->type->release)
 140                 serial->type->release(serial);
 141
 142         /* Now that nothing is using the ports, they can be freed */
 143         for (i = 0; i < serial->num_port_pointers; ++i) {
 144                 port = serial->port[i];
 145                 if (port) {
 146                         port->serial = NULL;
 147                         put_device(&port->dev);
 148                 }
 149         }
 150
 151         usb_put_intf(serial->interface);
 152         usb_put_dev(serial->dev);
 153         kfree(serial);
 154 }
 155
 156 void usb_serial_put(struct usb_serial *serial)
 157 {
 158         kref_put(&serial->kref, destroy_serial);
 159 }
 160
 161 /*****************************************************************************
 162  * Driver tty interface functions
 163  *****************************************************************************/
 164
 165 /**
 166  * serial_install - install tty
 167  * @driver: the driver (USB in our case)
 168  * @tty: the tty being created
 169  *
 170  * Create the termios objects for this tty.  We use the default
 171  * USB serial settings but permit them to be overridden by
 172  * serial->type->init_termios.
 173  *
 174  * This is the first place a new tty gets used.  Hence this is where we
 175  * acquire references to the usb_serial structure and the driver module,
 176  * where we store a pointer to the port, and where we do an autoresume.
 177  * All these actions are reversed in serial_cleanup().
 178  */
 179 static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 180 {
 181         int idx = tty->index;
 182         struct usb_serial *serial;
 183         struct usb_serial_port *port;
 184         int retval = -ENODEV;
 185
 186         port = usb_serial_port_get_by_minor(idx);
 187         if (!port)
 188                 return retval;
 189
 190         serial = port->serial;
 191         if (!try_module_get(serial->type->driver.owner))
 192                 goto error_module_get;
 193
 194         retval = usb_autopm_get_interface(serial->interface);
 195         if (retval)
 196                 goto error_get_interface;
 197
 198         retval = tty_port_install(&port->port, driver, tty);
 199         if (retval)
 200                 goto error_init_termios;
 201
 202         mutex_unlock(&serial->disc_mutex);
 203
 204         /* allow the driver to update the settings */
 205         if (serial->type->init_termios)
 206                 serial->type->init_termios(tty);
 207
 208         tty->driver_data = port;
 209
 210         return retval;
 211
 212  error_init_termios:
 213         usb_autopm_put_interface(serial->interface);
 214  error_get_interface:
 215         module_put(serial->type->driver.owner);
 216  error_module_get:
 217         usb_serial_put(serial);
 218         mutex_unlock(&serial->disc_mutex);
 219         return retval;
 220 }
 221
 222 static int serial_port_activate(struct tty_port *tport, struct tty_struct *tty)
 223 {
 224         struct usb_serial_port *port =
 225                 container_of(tport, struct usb_serial_port, port);
 226         struct usb_serial *serial = port->serial;
 227         int retval;
 228
 229         mutex_lock(&serial->disc_mutex);
 230         if (serial->disconnected)
 231                 retval = -ENODEV;
 232         else
 233                 retval = port->serial->type->open(tty, port);
 234         mutex_unlock(&serial->disc_mutex);
 235
 236         if (retval < 0)
 237                 retval = usb_translate_errors(retval);
 238
 239         return retval;
 240 }
 241
 242 static int serial_open(struct tty_struct *tty, struct file *filp)
 243 {
 244         struct usb_serial_port *port = tty->driver_data;
 245
 246         dev_dbg(tty->dev, "%s\n", __func__);
 247
 248         return tty_port_open(&port->port, tty, filp);
 249 }
 250
 251 /**
 252  * serial_port_shutdown - shut down hardware
 253  * @tport: tty port to shut down
 254  *
 255  * Shut down a USB serial port. Serialized against activate by the
 256  * tport mutex and kept to matching open/close pairs
 257  * of calls by the ASYNCB_INITIALIZED flag.
 258  *
 259  * Not called if tty is console.
 260  */
 261 static void serial_port_shutdown(struct tty_port *tport)
 262 {
 263         struct usb_serial_port *port =
 264                 container_of(tport, struct usb_serial_port, port);
 265         struct usb_serial_driver *drv = port->serial->type;
 266
 267         if (drv->close)
 268                 drv->close(port);
 269 }
 270
 271 static void serial_hangup(struct tty_struct *tty)
 272 {
 273         struct usb_serial_port *port = tty->driver_data;
 274
 275         dev_dbg(tty->dev, "%s\n", __func__);
 276
 277         tty_port_hangup(&port->port);
 278 }
 279
 280 static void serial_close(struct tty_struct *tty, struct file *filp)
 281 {
 282         struct usb_serial_port *port = tty->driver_data;
 283
 284         dev_dbg(tty->dev, "%s\n", __func__);
 285
 286         tty_port_close(&port->port, tty, filp);
 287 }
 288
 289 /**
 290  * serial_cleanup - free resources post close/hangup
 291  * @port: port to free up
 292  *
 293  * Do the resource freeing and refcount dropping for the port.
 294  * Avoid freeing the console.
 295  *
 296  * Called asynchronously after the last tty kref is dropped.
 297  */
 298 static void serial_cleanup(struct tty_struct *tty)
 299 {
 300         struct usb_serial_port *port = tty->driver_data;
 301         struct usb_serial *serial;
 302         struct module *owner;
 303
 304         dev_dbg(tty->dev, "%s\n", __func__);
 305
 306         /* The console is magical.  Do not hang up the console hardware
 307          * or there will be tears.
 308          */
 309         if (port->port.console)
 310                 return;
 311
 312         tty->driver_data = NULL;
 313
 314         serial = port->serial;
 315         owner = serial->type->driver.owner;
 316
 317         mutex_lock(&serial->disc_mutex);
 318         if (!serial->disconnected)
 319                 usb_autopm_put_interface(serial->interface);
 320         mutex_unlock(&serial->disc_mutex);
 321
 322         usb_serial_put(serial);
 323         module_put(owner);
 324 }
 325
 326 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
 327                                                                 int count)
 328 {
 329         struct usb_serial_port *port = tty->driver_data;
 330         int retval = -ENODEV;
 331
 332         if (port->serial->dev->state == USB_STATE_NOTATTACHED)
 333                 goto exit;
 334
 335         dev_dbg(tty->dev, "%s - %d byte(s)\n", __func__, count);
 336
 337         retval = port->serial->type->write(tty, port, buf, count);
 338         if (retval < 0)
 339                 retval = usb_translate_errors(retval);
 340 exit:
 341         return retval;
 342 }
 343
 344 static int serial_write_room(struct tty_struct *tty)
 345 {
 346         struct usb_serial_port *port = tty->driver_data;
 347
 348         dev_dbg(tty->dev, "%s\n", __func__);
 349
 350         return port->serial->type->write_room(tty);
 351 }
 352
 353 static int serial_chars_in_buffer(struct tty_struct *tty)
 354 {
 355         struct usb_serial_port *port = tty->driver_data;
 356         struct usb_serial *serial = port->serial;
 357
 358         dev_dbg(tty->dev, "%s\n", __func__);
 359
 360         if (serial->disconnected)
 361                 return 0;
 362
 363         return serial->type->chars_in_buffer(tty);
 364 }
 365
 366 static void serial_wait_until_sent(struct tty_struct *tty, int timeout)
 367 {
 368         struct usb_serial_port *port = tty->driver_data;
 369         struct usb_serial *serial = port->serial;
 370
 371         dev_dbg(tty->dev, "%s\n", __func__);
 372
 373         if (!port->serial->type->wait_until_sent)
 374                 return;
 375
 376         mutex_lock(&serial->disc_mutex);
 377         if (!serial->disconnected)
 378                 port->serial->type->wait_until_sent(tty, timeout);
 379         mutex_unlock(&serial->disc_mutex);
 380 }
 381
 382 static void serial_throttle(struct tty_struct *tty)
 383 {
 384         struct usb_serial_port *port = tty->driver_data;
 385
 386         dev_dbg(tty->dev, "%s\n", __func__);
 387
 388         if (port->serial->type->throttle)
 389                 port->serial->type->throttle(tty);
 390 }
 391
 392 static void serial_unthrottle(struct tty_struct *tty)
 393 {
 394         struct usb_serial_port *port = tty->driver_data;
 395
 396         dev_dbg(tty->dev, "%s\n", __func__);
 397
 398         if (port->serial->type->unthrottle)
 399                 port->serial->type->unthrottle(tty);
 400 }
 401
 402 static int serial_ioctl(struct tty_struct *tty,
 403                                         unsigned int cmd, unsigned long arg)
 404 {
 405         struct usb_serial_port *port = tty->driver_data;
 406         int retval = -ENOIOCTLCMD;
 407
 408         dev_dbg(tty->dev, "%s - cmd 0x%.4x\n", __func__, cmd);
 409
 410         switch (cmd) {
 411         case TIOCMIWAIT:
 412                 if (port->serial->type->tiocmiwait)
 413                         retval = port->serial->type->tiocmiwait(tty, arg);
 414                 break;
 415         default:
 416                 if (port->serial->type->ioctl)
 417                         retval = port->serial->type->ioctl(tty, cmd, arg);
 418         }
 419
 420         return retval;
 421 }
 422
 423 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 424 {
 425         struct usb_serial_port *port = tty->driver_data;
 426
 427         dev_dbg(tty->dev, "%s\n", __func__);
 428
 429         if (port->serial->type->set_termios)
 430                 port->serial->type->set_termios(tty, port, old);
 431         else
 432                 tty_termios_copy_hw(&tty->termios, old);
 433 }
 434
 435 static int serial_break(struct tty_struct *tty, int break_state)
 436 {
 437         struct usb_serial_port *port = tty->driver_data;
 438
 439         dev_dbg(tty->dev, "%s\n", __func__);
 440
 441         if (port->serial->type->break_ctl)
 442                 port->serial->type->break_ctl(tty, break_state);
 443
 444         return 0;
 445 }
 446
 447 static int serial_proc_show(struct seq_file *m, void *v)
 448 {
 449         struct usb_serial *serial;
 450         struct usb_serial_port *port;
 451         int i;
 452         char tmp[40];
 453
 454         seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
 455         for (i = 0; i < USB_SERIAL_TTY_MINORS; ++i) {
 456                 port = usb_serial_port_get_by_minor(i);
 457                 if (port == NULL)
 458                         continue;
 459                 serial = port->serial;
 460
 461                 seq_printf(m, "%d:", i);
 462                 if (serial->type->driver.owner)
 463                         seq_printf(m, " module:%s",
 464                                 module_name(serial->type->driver.owner));
 465                 seq_printf(m, " name:\"%s\"",
 466                                 serial->type->description);
 467                 seq_printf(m, " vendor:%04x product:%04x",
 468                         le16_to_cpu(serial->dev->descriptor.idVendor),
 469                         le16_to_cpu(serial->dev->descriptor.idProduct));
 470                 seq_printf(m, " num_ports:%d", serial->num_ports);
 471                 seq_printf(m, " port:%d", port->port_number);
 472                 usb_make_path(serial->dev, tmp, sizeof(tmp));
 473                 seq_printf(m, " path:%s", tmp);
 474
 475                 seq_putc(m, '\n');
 476                 usb_serial_put(serial);
 477                 mutex_unlock(&serial->disc_mutex);
 478         }
 479         return 0;
 480 }
 481
 482 static int serial_proc_open(struct inode *inode, struct file *file)
 483 {
 484         return single_open(file, serial_proc_show, NULL);
 485 }
 486
 487 static const struct file_operations serial_proc_fops = {
 488         .owner          = THIS_MODULE,
 489         .open           = serial_proc_open,
 490         .read           = seq_read,
 491         .llseek         = seq_lseek,
 492         .release        = single_release,
 493 };
 494
 495 static int serial_tiocmget(struct tty_struct *tty)
 496 {
 497         struct usb_serial_port *port = tty->driver_data;
 498
 499         dev_dbg(tty->dev, "%s\n", __func__);
 500
 501         if (port->serial->type->tiocmget)
 502                 return port->serial->type->tiocmget(tty);
 503         return -EINVAL;
 504 }
 505
 506 static int serial_tiocmset(struct tty_struct *tty,
 507                             unsigned int set, unsigned int clear)
 508 {
 509         struct usb_serial_port *port = tty->driver_data;
 510
 511         dev_dbg(tty->dev, "%s\n", __func__);
 512
 513         if (port->serial->type->tiocmset)
 514                 return port->serial->type->tiocmset(tty, set, clear);
 515         return -EINVAL;
 516 }
 517
 518 static int serial_get_icount(struct tty_struct *tty,
 519                                 struct serial_icounter_struct *icount)
 520 {
 521         struct usb_serial_port *port = tty->driver_data;
 522
 523         dev_dbg(tty->dev, "%s\n", __func__);
 524
 525         if (port->serial->type->get_icount)
 526                 return port->serial->type->get_icount(tty, icount);
 527         return -EINVAL;
 528 }
 529
 530 /*
 531  * We would be calling tty_wakeup here, but unfortunately some line
 532  * disciplines have an annoying habit of calling tty->write from
 533  * the write wakeup callback (e.g. n_hdlc.c).
 534  */
 535 void usb_serial_port_softint(struct usb_serial_port *port)
 536 {
 537         schedule_work(&port->work);
 538 }
 539 EXPORT_SYMBOL_GPL(usb_serial_port_softint);
 540
 541 static void usb_serial_port_work(struct work_struct *work)
 542 {
 543         struct usb_serial_port *port =
 544                 container_of(work, struct usb_serial_port, work);
 545
 546         tty_port_tty_wakeup(&port->port);
 547 }
 548
 549 static void usb_serial_port_poison_urbs(struct usb_serial_port *port)
 550 {
 551         int i;
 552
 553         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 554                 usb_poison_urb(port->read_urbs[i]);
 555         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 556                 usb_poison_urb(port->write_urbs[i]);
 557
 558         usb_poison_urb(port->interrupt_in_urb);
 559         usb_poison_urb(port->interrupt_out_urb);
 560 }
 561
 562 static void usb_serial_port_unpoison_urbs(struct usb_serial_port *port)
 563 {
 564         int i;
 565
 566         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 567                 usb_unpoison_urb(port->read_urbs[i]);
 568         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 569                 usb_unpoison_urb(port->write_urbs[i]);
 570
 571         usb_unpoison_urb(port->interrupt_in_urb);
 572         usb_unpoison_urb(port->interrupt_out_urb);
 573 }
 574
 575 static void usb_serial_port_release(struct device *dev)
 576 {
 577         struct usb_serial_port *port = to_usb_serial_port(dev);
 578         int i;
 579
 580         dev_dbg(dev, "%s\n", __func__);
 581
 582         usb_free_urb(port->interrupt_in_urb);
 583         usb_free_urb(port->interrupt_out_urb);
 584         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 585                 usb_free_urb(port->read_urbs[i]);
 586                 kfree(port->bulk_in_buffers[i]);
 587         }
 588         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 589                 usb_free_urb(port->write_urbs[i]);
 590                 kfree(port->bulk_out_buffers[i]);
 591         }
 592         kfifo_free(&port->write_fifo);
 593         kfree(port->interrupt_in_buffer);
 594         kfree(port->interrupt_out_buffer);
 595         tty_port_destroy(&port->port);
 596         kfree(port);
 597 }
 598
 599 static struct usb_serial *create_serial(struct usb_device *dev,
 600                                         struct usb_interface *interface,
 601                                         struct usb_serial_driver *driver)
 602 {
 603         struct usb_serial *serial;
 604
 605         serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 606         if (!serial)
 607                 return NULL;
 608         serial->dev = usb_get_dev(dev);
 609         serial->type = driver;
 610         serial->interface = usb_get_intf(interface);
 611         kref_init(&serial->kref);
 612         mutex_init(&serial->disc_mutex);
 613         serial->minors_reserved = 0;
 614
 615         return serial;
 616 }
 617
 618 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 619                                             struct usb_serial_driver *drv)
 620 {
 621         struct usb_dynid *dynid;
 622
 623         spin_lock(&drv->dynids.lock);
 624         list_for_each_entry(dynid, &drv->dynids.list, node) {
 625                 if (usb_match_one_id(intf, &dynid->id)) {
 626                         spin_unlock(&drv->dynids.lock);
 627                         return &dynid->id;
 628                 }
 629         }
 630         spin_unlock(&drv->dynids.lock);
 631         return NULL;
 632 }
 633
 634 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 635                                                 struct usb_interface *intf)
 636 {
 637         const struct usb_device_id *id;
 638
 639         id = usb_match_id(intf, drv->id_table);
 640         if (id) {
 641                 dev_dbg(&intf->dev, "static descriptor matches\n");
 642                 goto exit;
 643         }
 644         id = match_dynamic_id(intf, drv);
 645         if (id)
 646                 dev_dbg(&intf->dev, "dynamic descriptor matches\n");
 647 exit:
 648         return id;
 649 }
 650
 651 /* Caller must hold table_lock */
 652 static struct usb_serial_driver *search_serial_device(
 653                                         struct usb_interface *iface)
 654 {
 655         const struct usb_device_id *id = NULL;
 656         struct usb_serial_driver *drv;
 657         struct usb_driver *driver = to_usb_driver(iface->dev.driver);
 658
 659         /* Check if the usb id matches a known device */
 660         list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 661                 if (drv->usb_driver == driver)
 662                         id = get_iface_id(drv, iface);
 663                 if (id)
 664                         return drv;
 665         }
 666
 667         return NULL;
 668 }
 669
 670 static int serial_port_carrier_raised(struct tty_port *port)
 671 {
 672         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 673         struct usb_serial_driver *drv = p->serial->type;
 674
 675         if (drv->carrier_raised)
 676                 return drv->carrier_raised(p);
 677         /* No carrier control - don't block */
 678         return 1;
 679 }
 680
 681 static void serial_port_dtr_rts(struct tty_port *port, int on)
 682 {
 683         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 684         struct usb_serial *serial = p->serial;
 685         struct usb_serial_driver *drv = serial->type;
 686
 687         if (!drv->dtr_rts)
 688                 return;
 689         /*
 690          * Work-around bug in the tty-layer which can result in dtr_rts
 691          * being called after a disconnect (and tty_unregister_device
 692          * has returned). Remove once bug has been squashed.
 693          */
 694         mutex_lock(&serial->disc_mutex);
 695         if (!serial->disconnected)
 696                 drv->dtr_rts(p, on);
 697         mutex_unlock(&serial->disc_mutex);
 698 }
 699
 700 static const struct tty_port_operations serial_port_ops = {
 701         .carrier_raised         = serial_port_carrier_raised,
 702         .dtr_rts                = serial_port_dtr_rts,
 703         .activate               = serial_port_activate,
 704         .shutdown               = serial_port_shutdown,
 705 };
 706
 707 static int usb_serial_probe(struct usb_interface *interface,
 708                                const struct usb_device_id *id)
 709 {
 710         struct device *ddev = &interface->dev;
 711         struct usb_device *dev = interface_to_usbdev(interface);
 712         struct usb_serial *serial = NULL;
 713         struct usb_serial_port *port;
 714         struct usb_host_interface *iface_desc;
 715         struct usb_endpoint_descriptor *endpoint;
 716         struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
 717         struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
 718         struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
 719         struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 720         struct usb_serial_driver *type = NULL;
 721         int retval;
 722         int buffer_size;
 723         int i;
 724         int j;
 725         int num_interrupt_in = 0;
 726         int num_interrupt_out = 0;
 727         int num_bulk_in = 0;
 728         int num_bulk_out = 0;
 729         int num_ports = 0;
 730         int max_endpoints;
 731
 732         mutex_lock(&table_lock);
 733         type = search_serial_device(interface);
 734         if (!type) {
 735                 mutex_unlock(&table_lock);
 736                 dev_dbg(ddev, "none matched\n");
 737                 return -ENODEV;
 738         }
 739
 740         if (!try_module_get(type->driver.owner)) {
 741                 mutex_unlock(&table_lock);
 742                 dev_err(ddev, "module get failed, exiting\n");
 743                 return -EIO;
 744         }
 745         mutex_unlock(&table_lock);
 746
 747         serial = create_serial(dev, interface, type);
 748         if (!serial) {
 749                 module_put(type->driver.owner);
 750                 return -ENOMEM;
 751         }
 752
 753         /* if this device type has a probe function, call it */
 754         if (type->probe) {
 755                 const struct usb_device_id *id;
 756
 757                 id = get_iface_id(type, interface);
 758                 retval = type->probe(serial, id);
 759
 760                 if (retval) {
 761                         dev_dbg(ddev, "sub driver rejected device\n");
 762                         usb_serial_put(serial);
 763                         module_put(type->driver.owner);
 764                         return retval;
 765                 }
 766         }
 767
 768         /* descriptor matches, let's find the endpoints needed */
 769         /* check out the endpoints */
 770         iface_desc = interface->cur_altsetting;
 771         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 772                 endpoint = &iface_desc->endpoint[i].desc;
 773
 774                 if (usb_endpoint_is_bulk_in(endpoint)) {
 775                         /* we found a bulk in endpoint */
 776                         dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
 777                         bulk_in_endpoint[num_bulk_in] = endpoint;
 778                         ++num_bulk_in;
 779                 }
 780
 781                 if (usb_endpoint_is_bulk_out(endpoint)) {
 782                         /* we found a bulk out endpoint */
 783                         dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
 784                         bulk_out_endpoint[num_bulk_out] = endpoint;
 785                         ++num_bulk_out;
 786                 }
 787
 788                 if (usb_endpoint_is_int_in(endpoint)) {
 789                         /* we found a interrupt in endpoint */
 790                         dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
 791                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 792                         ++num_interrupt_in;
 793                 }
 794
 795                 if (usb_endpoint_is_int_out(endpoint)) {
 796                         /* we found an interrupt out endpoint */
 797                         dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
 798                         interrupt_out_endpoint[num_interrupt_out] = endpoint;
 799                         ++num_interrupt_out;
 800                 }
 801         }
 802
 803 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 804         /* BEGIN HORRIBLE HACK FOR PL2303 */
 805         /* this is needed due to the looney way its endpoints are set up */
 806         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 807              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 808             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 809              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 810             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 811              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 812             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 813              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 814                 if (interface != dev->actconfig->interface[0]) {
 815                         /* check out the endpoints of the other interface*/
 816                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 817                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 818                                 endpoint = &iface_desc->endpoint[i].desc;
 819                                 if (usb_endpoint_is_int_in(endpoint)) {
 820                                         /* we found a interrupt in endpoint */
 821                                         dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
 822                                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 823                                         ++num_interrupt_in;
 824                                 }
 825                         }
 826                 }
 827
 828                 /* Now make sure the PL-2303 is configured correctly.
 829                  * If not, give up now and hope this hack will work
 830                  * properly during a later invocation of usb_serial_probe
 831                  */
 832                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 833                         dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 834                         usb_serial_put(serial);
 835                         module_put(type->driver.owner);
 836                         return -ENODEV;
 837                 }
 838         }
 839         /* END HORRIBLE HACK FOR PL2303 */
 840 #endif
 841
 842 #ifdef CONFIG_USB_SERIAL_GENERIC
 843         if (type == &usb_serial_generic_device) {
 844                 num_ports = num_bulk_out;
 845                 if (num_ports == 0) {
 846                         dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
 847                         usb_serial_put(serial);
 848                         module_put(type->driver.owner);
 849                         return -EIO;
 850                 }
 851                 dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
 852                 dev_info(ddev, "Tell [email protected] to add your device to a proper driver.\n");
 853         }
 854 #endif
 855         if (!num_ports) {
 856                 /* if this device type has a calc_num_ports function, call it */
 857                 if (type->calc_num_ports)
 858                         num_ports = type->calc_num_ports(serial);
 859                 if (!num_ports)
 860                         num_ports = type->num_ports;
 861         }
 862
 863         serial->num_ports = num_ports;
 864         serial->num_bulk_in = num_bulk_in;
 865         serial->num_bulk_out = num_bulk_out;
 866         serial->num_interrupt_in = num_interrupt_in;
 867         serial->num_interrupt_out = num_interrupt_out;
 868
 869         /* found all that we need */
 870         dev_info(ddev, "%s converter detected\n", type->description);
 871
 872         /* create our ports, we need as many as the max endpoints */
 873         /* we don't use num_ports here because some devices have more
 874            endpoint pairs than ports */
 875         max_endpoints = max(num_bulk_in, num_bulk_out);
 876         max_endpoints = max(max_endpoints, num_interrupt_in);
 877         max_endpoints = max(max_endpoints, num_interrupt_out);
 878         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 879         serial->num_port_pointers = max_endpoints;
 880
 881         dev_dbg(ddev, "setting up %d port structures for this device", max_endpoints);
 882         for (i = 0; i < max_endpoints; ++i) {
 883                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 884                 if (!port)
 885                         goto probe_error;
 886                 tty_port_init(&port->port);
 887                 port->port.ops = &serial_port_ops;
 888                 port->serial = serial;
 889                 spin_lock_init(&port->lock);
 890                 /* Keep this for private driver use for the moment but
 891                    should probably go away */
 892                 INIT_WORK(&port->work, usb_serial_port_work);
 893                 serial->port[i] = port;
 894                 port->dev.parent = &interface->dev;
 895                 port->dev.driver = NULL;
 896                 port->dev.bus = &usb_serial_bus_type;
 897                 port->dev.release = &usb_serial_port_release;
 898                 device_initialize(&port->dev);
 899         }
 900
 901         /* set up the endpoint information */
 902         for (i = 0; i < num_bulk_in; ++i) {
 903                 endpoint = bulk_in_endpoint[i];
 904                 port = serial->port[i];
 905                 buffer_size = max_t(int, serial->type->bulk_in_size,
 906                                 usb_endpoint_maxp(endpoint));
 907                 port->bulk_in_size = buffer_size;
 908                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 909
 910                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 911                         set_bit(j, &port->read_urbs_free);
 912                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 913                         if (!port->read_urbs[j])
 914                                 goto probe_error;
 915                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 916                                                                 GFP_KERNEL);
 917                         if (!port->bulk_in_buffers[j])
 918                                 goto probe_error;
 919                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 920                                         usb_rcvbulkpipe(dev,
 921                                                 endpoint->bEndpointAddress),
 922                                         port->bulk_in_buffers[j], buffer_size,
 923                                         serial->type->read_bulk_callback,
 924                                         port);
 925                 }
 926
 927                 port->read_urb = port->read_urbs[0];
 928                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 929         }
 930
 931         for (i = 0; i < num_bulk_out; ++i) {
 932                 endpoint = bulk_out_endpoint[i];
 933                 port = serial->port[i];
 934                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 935                         goto probe_error;
 936                 buffer_size = serial->type->bulk_out_size;
 937                 if (!buffer_size)
 938                         buffer_size = usb_endpoint_maxp(endpoint);
 939                 port->bulk_out_size = buffer_size;
 940                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 941
 942                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 943                         set_bit(j, &port->write_urbs_free);
 944                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 945                         if (!port->write_urbs[j])
 946                                 goto probe_error;
 947                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 948                                                                 GFP_KERNEL);
 949                         if (!port->bulk_out_buffers[j])
 950                                 goto probe_error;
 951                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 952                                         usb_sndbulkpipe(dev,
 953                                                 endpoint->bEndpointAddress),
 954                                         port->bulk_out_buffers[j], buffer_size,
 955                                         serial->type->write_bulk_callback,
 956                                         port);
 957                 }
 958
 959                 port->write_urb = port->write_urbs[0];
 960                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 961         }
 962
 963         if (serial->type->read_int_callback) {
 964                 for (i = 0; i < num_interrupt_in; ++i) {
 965                         endpoint = interrupt_in_endpoint[i];
 966                         port = serial->port[i];
 967                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 968                         if (!port->interrupt_in_urb)
 969                                 goto probe_error;
 970                         buffer_size = usb_endpoint_maxp(endpoint);
 971                         port->interrupt_in_endpointAddress =
 972                                                 endpoint->bEndpointAddress;
 973                         port->interrupt_in_buffer = kmalloc(buffer_size,
 974                                                                 GFP_KERNEL);
 975                         if (!port->interrupt_in_buffer)
 976                                 goto probe_error;
 977                         usb_fill_int_urb(port->interrupt_in_urb, dev,
 978                                 usb_rcvintpipe(dev,
 979                                                 endpoint->bEndpointAddress),
 980                                 port->interrupt_in_buffer, buffer_size,
 981                                 serial->type->read_int_callback, port,
 982                                 endpoint->bInterval);
 983                 }
 984         } else if (num_interrupt_in) {
 985                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
 986         }
 987
 988         if (serial->type->write_int_callback) {
 989                 for (i = 0; i < num_interrupt_out; ++i) {
 990                         endpoint = interrupt_out_endpoint[i];
 991                         port = serial->port[i];
 992                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 993                         if (!port->interrupt_out_urb)
 994                                 goto probe_error;
 995                         buffer_size = usb_endpoint_maxp(endpoint);
 996                         port->interrupt_out_size = buffer_size;
 997                         port->interrupt_out_endpointAddress =
 998                                                 endpoint->bEndpointAddress;
 999                         port->interrupt_out_buffer = kmalloc(buffer_size,
1000                                                                 GFP_KERNEL);
1001                         if (!port->interrupt_out_buffer)
1002                                 goto probe_error;
1003                         usb_fill_int_urb(port->interrupt_out_urb, dev,
1004                                 usb_sndintpipe(dev,
1005                                                   endpoint->bEndpointAddress),
1006                                 port->interrupt_out_buffer, buffer_size,
1007                                 serial->type->write_int_callback, port,
1008                                 endpoint->bInterval);
1009                 }
1010         } else if (num_interrupt_out) {
1011                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1012         }
1013
1014         usb_set_intfdata(interface, serial);
1015
1016         /* if this device type has an attach function, call it */
1017         if (type->attach) {
1018                 retval = type->attach(serial);
1019                 if (retval < 0)
1020                         goto probe_error;
1021                 serial->attached = 1;
1022                 if (retval > 0) {
1023                         /* quietly accept this device, but don't bind to a
1024                            serial port as it's about to disappear */
1025                         serial->num_ports = 0;
1026                         goto exit;
1027                 }
1028         } else {
1029                 serial->attached = 1;
1030         }
1031
1032         /* Avoid race with tty_open and serial_install by setting the
1033          * disconnected flag and not clearing it until all ports have been
1034          * registered.
1035          */
1036         serial->disconnected = 1;
1037
1038         if (allocate_minors(serial, num_ports)) {
1039                 dev_err(ddev, "No more free serial minor numbers\n");
1040                 goto probe_error;
1041         }
1042
1043         /* register all of the individual ports with the driver core */
1044         for (i = 0; i < num_ports; ++i) {
1045                 port = serial->port[i];
1046                 dev_set_name(&port->dev, "ttyUSB%d", port->minor);
1047                 dev_dbg(ddev, "registering %s", dev_name(&port->dev));
1048                 device_enable_async_suspend(&port->dev);
1049
1050                 retval = device_add(&port->dev);
1051                 if (retval)
1052                         dev_err(ddev, "Error registering port device, continuing\n");
1053         }
1054
1055         serial->disconnected = 0;
1056
1057         usb_serial_console_init(serial->port[0]->minor);
1058 exit:
1059         module_put(type->driver.owner);
1060         return 0;
1061
1062 probe_error:
1063         usb_serial_put(serial);
1064         module_put(type->driver.owner);
1065         return -EIO;
1066 }
1067
1068 static void usb_serial_disconnect(struct usb_interface *interface)
1069 {
1070         int i;
1071         struct usb_serial *serial = usb_get_intfdata(interface);
1072         struct device *dev = &interface->dev;
1073         struct usb_serial_port *port;
1074
1075         usb_serial_console_disconnect(serial);
1076
1077         mutex_lock(&serial->disc_mutex);
1078         /* must set a flag, to signal subdrivers */
1079         serial->disconnected = 1;
1080         mutex_unlock(&serial->disc_mutex);
1081
1082         for (i = 0; i < serial->num_ports; ++i) {
1083                 port = serial->port[i];
1084                 if (port) {
1085                         struct tty_struct *tty = tty_port_tty_get(&port->port);
1086                         if (tty) {
1087                                 tty_vhangup(tty);
1088                                 tty_kref_put(tty);
1089                         }
1090                         usb_serial_port_poison_urbs(port);
1091                         wake_up_interruptible(&port->port.delta_msr_wait);
1092                         cancel_work_sync(&port->work);
1093                         if (device_is_registered(&port->dev))
1094                                 device_del(&port->dev);
1095                 }
1096         }
1097         if (serial->type->disconnect)
1098                 serial->type->disconnect(serial);
1099
1100         /* let the last holder of this object cause it to be cleaned up */
1101         usb_serial_put(serial);
1102         dev_info(dev, "device disconnected\n");
1103 }
1104
1105 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1106 {
1107         struct usb_serial *serial = usb_get_intfdata(intf);
1108         struct usb_serial_port *port;
1109         int i, r = 0;
1110
1111         serial->suspending = 1;
1112
1113         /*
1114          * serial->type->suspend() MUST return 0 in system sleep context,
1115          * otherwise, the resume callback has to recover device from
1116          * previous suspend failure.
1117          */
1118         if (serial->type->suspend) {
1119                 r = serial->type->suspend(serial, message);
1120                 if (r < 0) {
1121                         serial->suspending = 0;
1122                         goto err_out;
1123                 }
1124         }
1125
1126         for (i = 0; i < serial->num_ports; ++i) {
1127                 port = serial->port[i];
1128                 if (port)
1129                         usb_serial_port_poison_urbs(port);
1130         }
1131
1132 err_out:
1133         return r;
1134 }
1135 EXPORT_SYMBOL(usb_serial_suspend);
1136
1137 static void usb_serial_unpoison_port_urbs(struct usb_serial *serial)
1138 {
1139         struct usb_serial_port *port;
1140         int i;
1141
1142         for (i = 0; i < serial->num_ports; ++i) {
1143                 port = serial->port[i];
1144                 if (port)
1145                         usb_serial_port_unpoison_urbs(port);
1146         }
1147 }
1148
1149 int usb_serial_resume(struct usb_interface *intf)
1150 {
1151         struct usb_serial *serial = usb_get_intfdata(intf);
1152         int rv;
1153
1154         usb_serial_unpoison_port_urbs(serial);
1155
1156         serial->suspending = 0;
1157         if (serial->type->resume)
1158                 rv = serial->type->resume(serial);
1159         else
1160                 rv = usb_serial_generic_resume(serial);
1161
1162         return rv;
1163 }
1164 EXPORT_SYMBOL(usb_serial_resume);
1165
1166 static int usb_serial_reset_resume(struct usb_interface *intf)
1167 {
1168         struct usb_serial *serial = usb_get_intfdata(intf);
1169         int rv;
1170
1171         usb_serial_unpoison_port_urbs(serial);
1172
1173         serial->suspending = 0;
1174         if (serial->type->reset_resume)
1175                 rv = serial->type->reset_resume(serial);
1176         else {
1177                 rv = -EOPNOTSUPP;
1178                 intf->needs_binding = 1;
1179         }
1180
1181         return rv;
1182 }
1183
1184 static const struct tty_operations serial_ops = {
1185         .open =                 serial_open,
1186         .close =                serial_close,
1187         .write =                serial_write,
1188         .hangup =               serial_hangup,
1189         .write_room =           serial_write_room,
1190         .ioctl =                serial_ioctl,
1191         .set_termios =          serial_set_termios,
1192         .throttle =             serial_throttle,
1193         .unthrottle =           serial_unthrottle,
1194         .break_ctl =            serial_break,
1195         .chars_in_buffer =      serial_chars_in_buffer,
1196         .wait_until_sent =      serial_wait_until_sent,
1197         .tiocmget =             serial_tiocmget,
1198         .tiocmset =             serial_tiocmset,
1199         .get_icount =           serial_get_icount,
1200         .cleanup =              serial_cleanup,
1201         .install =              serial_install,
1202         .proc_fops =            &serial_proc_fops,
1203 };
1204
1205
1206 struct tty_driver *usb_serial_tty_driver;
1207
1208 /* Driver structure we register with the USB core */
1209 static struct usb_driver usb_serial_driver = {
1210         .name =         "usbserial",
1211         .probe =        usb_serial_probe,
1212         .disconnect =   usb_serial_disconnect,
1213         .suspend =      usb_serial_suspend,
1214         .resume =       usb_serial_resume,
1215         .no_dynamic_id =        1,
1216         .supports_autosuspend = 1,
1217 };
1218
1219 static int __init usb_serial_init(void)
1220 {
1221         int result;
1222
1223         usb_serial_tty_driver = alloc_tty_driver(USB_SERIAL_TTY_MINORS);
1224         if (!usb_serial_tty_driver)
1225                 return -ENOMEM;
1226
1227         /* Initialize our global data */
1228         result = bus_register(&usb_serial_bus_type);
1229         if (result) {
1230                 pr_err("%s - registering bus driver failed\n", __func__);
1231                 goto exit_bus;
1232         }
1233
1234         usb_serial_tty_driver->driver_name = "usbserial";
1235         usb_serial_tty_driver->name = "ttyUSB";
1236         usb_serial_tty_driver->major = USB_SERIAL_TTY_MAJOR;
1237         usb_serial_tty_driver->minor_start = 0;
1238         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1239         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1240         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1241                                                 TTY_DRIVER_DYNAMIC_DEV;
1242         usb_serial_tty_driver->init_termios = tty_std_termios;
1243         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1244                                                         | HUPCL | CLOCAL;
1245         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1246         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1247         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1248         result = tty_register_driver(usb_serial_tty_driver);
1249         if (result) {
1250                 pr_err("%s - tty_register_driver failed\n", __func__);
1251                 goto exit_reg_driver;
1252         }
1253
1254         /* register the USB driver */
1255         result = usb_register(&usb_serial_driver);
1256         if (result < 0) {
1257                 pr_err("%s - usb_register failed\n", __func__);
1258                 goto exit_tty;
1259         }
1260
1261         /* register the generic driver, if we should */
1262         result = usb_serial_generic_register();
1263         if (result < 0) {
1264                 pr_err("%s - registering generic driver failed\n", __func__);
1265                 goto exit_generic;
1266         }
1267
1268         return result;
1269
1270 exit_generic:
1271         usb_deregister(&usb_serial_driver);
1272
1273 exit_tty:
1274         tty_unregister_driver(usb_serial_tty_driver);
1275
1276 exit_reg_driver:
1277         bus_unregister(&usb_serial_bus_type);
1278
1279 exit_bus:
1280         pr_err("%s - returning with error %d\n", __func__, result);
1281         put_tty_driver(usb_serial_tty_driver);
1282         return result;
1283 }
1284
1285
1286 static void __exit usb_serial_exit(void)
1287 {
1288         usb_serial_console_exit();
1289
1290         usb_serial_generic_deregister();
1291
1292         usb_deregister(&usb_serial_driver);
1293         tty_unregister_driver(usb_serial_tty_driver);
1294         put_tty_driver(usb_serial_tty_driver);
1295         bus_unregister(&usb_serial_bus_type);
1296 }
1297
1298
1299 module_init(usb_serial_init);
1300 module_exit(usb_serial_exit);
1301
1302 #define set_to_generic_if_null(type, function)                          \
1303         do {                                                            \
1304                 if (!type->function) {                                  \
1305                         type->function = usb_serial_generic_##function; \
1306                         pr_debug("%s: using generic " #function "\n",   \
1307                                                 type->driver.name);     \
1308                 }                                                       \
1309         } while (0)
1310
1311 static void usb_serial_operations_init(struct usb_serial_driver *device)
1312 {
1313         set_to_generic_if_null(device, open);
1314         set_to_generic_if_null(device, write);
1315         set_to_generic_if_null(device, close);
1316         set_to_generic_if_null(device, write_room);
1317         set_to_generic_if_null(device, chars_in_buffer);
1318         if (device->tx_empty)
1319                 set_to_generic_if_null(device, wait_until_sent);
1320         set_to_generic_if_null(device, read_bulk_callback);
1321         set_to_generic_if_null(device, write_bulk_callback);
1322         set_to_generic_if_null(device, process_read_urb);
1323         set_to_generic_if_null(device, prepare_write_buffer);
1324 }
1325
1326 static int usb_serial_register(struct usb_serial_driver *driver)
1327 {
1328         int retval;
1329
1330         if (usb_disabled())
1331                 return -ENODEV;
1332
1333         if (!driver->description)
1334                 driver->description = driver->driver.name;
1335         if (!driver->usb_driver) {
1336                 WARN(1, "Serial driver %s has no usb_driver\n",
1337                                 driver->description);
1338                 return -EINVAL;
1339         }
1340
1341         usb_serial_operations_init(driver);
1342
1343         /* Add this device to our list of devices */
1344         mutex_lock(&table_lock);
1345         list_add(&driver->driver_list, &usb_serial_driver_list);
1346
1347         retval = usb_serial_bus_register(driver);
1348         if (retval) {
1349                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1350                 list_del(&driver->driver_list);
1351         } else
1352                 pr_info("USB Serial support registered for %s\n", driver->description);
1353
1354         mutex_unlock(&table_lock);
1355         return retval;
1356 }
1357
1358 static void usb_serial_deregister(struct usb_serial_driver *device)
1359 {
1360         pr_info("USB Serial deregistering driver %s\n", device->description);
1361         mutex_lock(&table_lock);
1362         list_del(&device->driver_list);
1363         usb_serial_bus_deregister(device);
1364         mutex_unlock(&table_lock);
1365 }
1366
1367 /**
1368  * usb_serial_register_drivers - register drivers for a usb-serial module
1369  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1370  * @name: name of the usb_driver for this set of @serial_drivers
1371  * @id_table: list of all devices this @serial_drivers set binds to
1372  *
1373  * Registers all the drivers in the @serial_drivers array, and dynamically
1374  * creates a struct usb_driver with the name @name and id_table of @id_table.
1375  */
1376 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1377                                 const char *name,
1378                                 const struct usb_device_id *id_table)
1379 {
1380         int rc;
1381         struct usb_driver *udriver;
1382         struct usb_serial_driver * const *sd;
1383
1384         /*
1385          * udriver must be registered before any of the serial drivers,
1386          * because the store_new_id() routine for the serial drivers (in
1387          * bus.c) probes udriver.
1388          *
1389          * Performance hack: We don't want udriver to be probed until
1390          * the serial drivers are registered, because the probe would
1391          * simply fail for lack of a matching serial driver.
1392          * So we leave udriver's id_table set to NULL until we are all set.
1393          *
1394          * Suspend/resume support is implemented in the usb-serial core,
1395          * so fill in the PM-related fields in udriver.
1396          */
1397         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1398         if (!udriver)
1399                 return -ENOMEM;
1400
1401         udriver->name = name;
1402         udriver->no_dynamic_id = 1;
1403         udriver->supports_autosuspend = 1;
1404         udriver->suspend = usb_serial_suspend;
1405         udriver->resume = usb_serial_resume;
1406         udriver->probe = usb_serial_probe;
1407         udriver->disconnect = usb_serial_disconnect;
1408
1409         /* we only set the reset_resume field if the serial_driver has one */
1410         for (sd = serial_drivers; *sd; ++sd) {
1411                 if ((*sd)->reset_resume) {
1412                         udriver->reset_resume = usb_serial_reset_resume;
1413                         break;
1414                 }
1415         }
1416
1417         rc = usb_register(udriver);
1418         if (rc)
1419                 return rc;
1420
1421         for (sd = serial_drivers; *sd; ++sd) {
1422                 (*sd)->usb_driver = udriver;
1423                 rc = usb_serial_register(*sd);
1424                 if (rc)
1425                         goto failed;
1426         }
1427
1428         /* Now set udriver's id_table and look for matches */
1429         udriver->id_table = id_table;
1430         rc = driver_attach(&udriver->drvwrap.driver);
1431         return 0;
1432
1433  failed:
1434         while (sd-- > serial_drivers)
1435                 usb_serial_deregister(*sd);
1436         usb_deregister(udriver);
1437         return rc;
1438 }
1439 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1440
1441 /**
1442  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1443  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1444  *
1445  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1446  * frees the struct usb_driver that was created by the call to
1447  * usb_serial_register_drivers().
1448  */
1449 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1450 {
1451         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1452
1453         for (; *serial_drivers; ++serial_drivers)
1454                 usb_serial_deregister(*serial_drivers);
1455         usb_deregister(udriver);
1456         kfree(udriver);
1457 }
1458 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1459
1460 MODULE_AUTHOR(DRIVER_AUTHOR);
1461 MODULE_DESCRIPTION(DRIVER_DESC);
1462 MODULE_LICENSE("GPL");