Pileus Git - ~andy/linux/blob - 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
 546         tty_port_tty_wakeup(&port->port);
 547 }
 548
 549 static void kill_traffic(struct usb_serial_port *port)
 550 {
 551         int i;
 552
 553         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 554                 usb_kill_urb(port->read_urbs[i]);
 555         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 556                 usb_kill_urb(port->write_urbs[i]);
 557         /*
 558          * This is tricky.
 559          * Some drivers submit the read_urb in the
 560          * handler for the write_urb or vice versa
 561          * this order determines the order in which
 562          * usb_kill_urb() must be used to reliably
 563          * kill the URBs. As it is unknown here,
 564          * both orders must be used in turn.
 565          * The call below is not redundant.
 566          */
 567         usb_kill_urb(port->read_urb);
 568         usb_kill_urb(port->interrupt_in_urb);
 569         usb_kill_urb(port->interrupt_out_urb);
 570 }
 571
 572 static void port_release(struct device *dev)
 573 {
 574         struct usb_serial_port *port = to_usb_serial_port(dev);
 575         int i;
 576
 577         dev_dbg(dev, "%s\n", __func__);
 578
 579         /*
 580          * Stop all the traffic before cancelling the work, so that
 581          * nobody will restart it by calling usb_serial_port_softint.
 582          */
 583         kill_traffic(port);
 584         cancel_work_sync(&port->work);
 585
 586         usb_free_urb(port->interrupt_in_urb);
 587         usb_free_urb(port->interrupt_out_urb);
 588         for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 589                 usb_free_urb(port->read_urbs[i]);
 590                 kfree(port->bulk_in_buffers[i]);
 591         }
 592         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 593                 usb_free_urb(port->write_urbs[i]);
 594                 kfree(port->bulk_out_buffers[i]);
 595         }
 596         kfifo_free(&port->write_fifo);
 597         kfree(port->interrupt_in_buffer);
 598         kfree(port->interrupt_out_buffer);
 599         tty_port_destroy(&port->port);
 600         kfree(port);
 601 }
 602
 603 static struct usb_serial *create_serial(struct usb_device *dev,
 604                                         struct usb_interface *interface,
 605                                         struct usb_serial_driver *driver)
 606 {
 607         struct usb_serial *serial;
 608
 609         serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 610         if (!serial) {
 611                 dev_err(&dev->dev, "%s - out of memory\n", __func__);
 612                 return NULL;
 613         }
 614         serial->dev = usb_get_dev(dev);
 615         serial->type = driver;
 616         serial->interface = usb_get_intf(interface);
 617         kref_init(&serial->kref);
 618         mutex_init(&serial->disc_mutex);
 619         serial->minor = SERIAL_TTY_NO_MINOR;
 620
 621         return serial;
 622 }
 623
 624 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 625                                             struct usb_serial_driver *drv)
 626 {
 627         struct usb_dynid *dynid;
 628
 629         spin_lock(&drv->dynids.lock);
 630         list_for_each_entry(dynid, &drv->dynids.list, node) {
 631                 if (usb_match_one_id(intf, &dynid->id)) {
 632                         spin_unlock(&drv->dynids.lock);
 633                         return &dynid->id;
 634                 }
 635         }
 636         spin_unlock(&drv->dynids.lock);
 637         return NULL;
 638 }
 639
 640 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 641                                                 struct usb_interface *intf)
 642 {
 643         const struct usb_device_id *id;
 644
 645         id = usb_match_id(intf, drv->id_table);
 646         if (id) {
 647                 dev_dbg(&intf->dev, "static descriptor matches\n");
 648                 goto exit;
 649         }
 650         id = match_dynamic_id(intf, drv);
 651         if (id)
 652                 dev_dbg(&intf->dev, "dynamic descriptor matches\n");
 653 exit:
 654         return id;
 655 }
 656
 657 /* Caller must hold table_lock */
 658 static struct usb_serial_driver *search_serial_device(
 659                                         struct usb_interface *iface)
 660 {
 661         const struct usb_device_id *id = NULL;
 662         struct usb_serial_driver *drv;
 663         struct usb_driver *driver = to_usb_driver(iface->dev.driver);
 664
 665         /* Check if the usb id matches a known device */
 666         list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 667                 if (drv->usb_driver == driver)
 668                         id = get_iface_id(drv, iface);
 669                 if (id)
 670                         return drv;
 671         }
 672
 673         return NULL;
 674 }
 675
 676 static int serial_carrier_raised(struct tty_port *port)
 677 {
 678         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 679         struct usb_serial_driver *drv = p->serial->type;
 680
 681         if (drv->carrier_raised)
 682                 return drv->carrier_raised(p);
 683         /* No carrier control - don't block */
 684         return 1;
 685 }
 686
 687 static void serial_dtr_rts(struct tty_port *port, int on)
 688 {
 689         struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 690         struct usb_serial *serial = p->serial;
 691         struct usb_serial_driver *drv = serial->type;
 692
 693         if (!drv->dtr_rts)
 694                 return;
 695         /*
 696          * Work-around bug in the tty-layer which can result in dtr_rts
 697          * being called after a disconnect (and tty_unregister_device
 698          * has returned). Remove once bug has been squashed.
 699          */
 700         mutex_lock(&serial->disc_mutex);
 701         if (!serial->disconnected)
 702                 drv->dtr_rts(p, on);
 703         mutex_unlock(&serial->disc_mutex);
 704 }
 705
 706 static const struct tty_port_operations serial_port_ops = {
 707         .carrier_raised = serial_carrier_raised,
 708         .dtr_rts = serial_dtr_rts,
 709         .activate = serial_activate,
 710         .shutdown = serial_down,
 711 };
 712
 713 static int usb_serial_probe(struct usb_interface *interface,
 714                                const struct usb_device_id *id)
 715 {
 716         struct device *ddev = &interface->dev;
 717         struct usb_device *dev = interface_to_usbdev(interface);
 718         struct usb_serial *serial = NULL;
 719         struct usb_serial_port *port;
 720         struct usb_host_interface *iface_desc;
 721         struct usb_endpoint_descriptor *endpoint;
 722         struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
 723         struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
 724         struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
 725         struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 726         struct usb_serial_driver *type = NULL;
 727         int retval;
 728         unsigned int minor;
 729         int buffer_size;
 730         int i;
 731         int j;
 732         int num_interrupt_in = 0;
 733         int num_interrupt_out = 0;
 734         int num_bulk_in = 0;
 735         int num_bulk_out = 0;
 736         int num_ports = 0;
 737         int max_endpoints;
 738
 739         mutex_lock(&table_lock);
 740         type = search_serial_device(interface);
 741         if (!type) {
 742                 mutex_unlock(&table_lock);
 743                 dev_dbg(ddev, "none matched\n");
 744                 return -ENODEV;
 745         }
 746
 747         if (!try_module_get(type->driver.owner)) {
 748                 mutex_unlock(&table_lock);
 749                 dev_err(ddev, "module get failed, exiting\n");
 750                 return -EIO;
 751         }
 752         mutex_unlock(&table_lock);
 753
 754         serial = create_serial(dev, interface, type);
 755         if (!serial) {
 756                 module_put(type->driver.owner);
 757                 dev_err(ddev, "%s - out of memory\n", __func__);
 758                 return -ENOMEM;
 759         }
 760
 761         /* if this device type has a probe function, call it */
 762         if (type->probe) {
 763                 const struct usb_device_id *id;
 764
 765                 id = get_iface_id(type, interface);
 766                 retval = type->probe(serial, id);
 767
 768                 if (retval) {
 769                         dev_dbg(ddev, "sub driver rejected device\n");
 770                         usb_serial_put(serial);
 771                         module_put(type->driver.owner);
 772                         return retval;
 773                 }
 774         }
 775
 776         /* descriptor matches, let's find the endpoints needed */
 777         /* check out the endpoints */
 778         iface_desc = interface->cur_altsetting;
 779         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 780                 endpoint = &iface_desc->endpoint[i].desc;
 781
 782                 if (usb_endpoint_is_bulk_in(endpoint)) {
 783                         /* we found a bulk in endpoint */
 784                         dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
 785                         bulk_in_endpoint[num_bulk_in] = endpoint;
 786                         ++num_bulk_in;
 787                 }
 788
 789                 if (usb_endpoint_is_bulk_out(endpoint)) {
 790                         /* we found a bulk out endpoint */
 791                         dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
 792                         bulk_out_endpoint[num_bulk_out] = endpoint;
 793                         ++num_bulk_out;
 794                 }
 795
 796                 if (usb_endpoint_is_int_in(endpoint)) {
 797                         /* we found a interrupt in endpoint */
 798                         dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
 799                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 800                         ++num_interrupt_in;
 801                 }
 802
 803                 if (usb_endpoint_is_int_out(endpoint)) {
 804                         /* we found an interrupt out endpoint */
 805                         dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
 806                         interrupt_out_endpoint[num_interrupt_out] = endpoint;
 807                         ++num_interrupt_out;
 808                 }
 809         }
 810
 811 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
 812         /* BEGIN HORRIBLE HACK FOR PL2303 */
 813         /* this is needed due to the looney way its endpoints are set up */
 814         if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
 815              (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
 816             ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
 817              (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
 818             ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
 819              (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
 820             ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 821              (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
 822                 if (interface != dev->actconfig->interface[0]) {
 823                         /* check out the endpoints of the other interface*/
 824                         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 825                         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 826                                 endpoint = &iface_desc->endpoint[i].desc;
 827                                 if (usb_endpoint_is_int_in(endpoint)) {
 828                                         /* we found a interrupt in endpoint */
 829                                         dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
 830                                         interrupt_in_endpoint[num_interrupt_in] = endpoint;
 831                                         ++num_interrupt_in;
 832                                 }
 833                         }
 834                 }
 835
 836                 /* Now make sure the PL-2303 is configured correctly.
 837                  * If not, give up now and hope this hack will work
 838                  * properly during a later invocation of usb_serial_probe
 839                  */
 840                 if (num_bulk_in == 0 || num_bulk_out == 0) {
 841                         dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
 842                         usb_serial_put(serial);
 843                         module_put(type->driver.owner);
 844                         return -ENODEV;
 845                 }
 846         }
 847         /* END HORRIBLE HACK FOR PL2303 */
 848 #endif
 849
 850 #ifdef CONFIG_USB_SERIAL_GENERIC
 851         if (type == &usb_serial_generic_device) {
 852                 num_ports = num_bulk_out;
 853                 if (num_ports == 0) {
 854                         dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
 855                         usb_serial_put(serial);
 856                         module_put(type->driver.owner);
 857                         return -EIO;
 858                 }
 859                 dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
 860                 dev_info(ddev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n");
 861         }
 862 #endif
 863         if (!num_ports) {
 864                 /* if this device type has a calc_num_ports function, call it */
 865                 if (type->calc_num_ports)
 866                         num_ports = type->calc_num_ports(serial);
 867                 if (!num_ports)
 868                         num_ports = type->num_ports;
 869         }
 870
 871         serial->num_ports = num_ports;
 872         serial->num_bulk_in = num_bulk_in;
 873         serial->num_bulk_out = num_bulk_out;
 874         serial->num_interrupt_in = num_interrupt_in;
 875         serial->num_interrupt_out = num_interrupt_out;
 876
 877         /* found all that we need */
 878         dev_info(ddev, "%s converter detected\n", type->description);
 879
 880         /* create our ports, we need as many as the max endpoints */
 881         /* we don't use num_ports here because some devices have more
 882            endpoint pairs than ports */
 883         max_endpoints = max(num_bulk_in, num_bulk_out);
 884         max_endpoints = max(max_endpoints, num_interrupt_in);
 885         max_endpoints = max(max_endpoints, num_interrupt_out);
 886         max_endpoints = max(max_endpoints, (int)serial->num_ports);
 887         serial->num_port_pointers = max_endpoints;
 888
 889         dev_dbg(ddev, "setting up %d port structures for this device", max_endpoints);
 890         for (i = 0; i < max_endpoints; ++i) {
 891                 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
 892                 if (!port)
 893                         goto probe_error;
 894                 tty_port_init(&port->port);
 895                 port->port.ops = &serial_port_ops;
 896                 port->serial = serial;
 897                 spin_lock_init(&port->lock);
 898                 init_waitqueue_head(&port->delta_msr_wait);
 899                 /* Keep this for private driver use for the moment but
 900                    should probably go away */
 901                 INIT_WORK(&port->work, usb_serial_port_work);
 902                 serial->port[i] = port;
 903                 port->dev.parent = &interface->dev;
 904                 port->dev.driver = NULL;
 905                 port->dev.bus = &usb_serial_bus_type;
 906                 port->dev.release = &port_release;
 907                 device_initialize(&port->dev);
 908         }
 909
 910         /* set up the endpoint information */
 911         for (i = 0; i < num_bulk_in; ++i) {
 912                 endpoint = bulk_in_endpoint[i];
 913                 port = serial->port[i];
 914                 buffer_size = max_t(int, serial->type->bulk_in_size,
 915                                 usb_endpoint_maxp(endpoint));
 916                 port->bulk_in_size = buffer_size;
 917                 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
 918
 919                 for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) {
 920                         set_bit(j, &port->read_urbs_free);
 921                         port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 922                         if (!port->read_urbs[j]) {
 923                                 dev_err(ddev, "No free urbs available\n");
 924                                 goto probe_error;
 925                         }
 926                         port->bulk_in_buffers[j] = kmalloc(buffer_size,
 927                                                                 GFP_KERNEL);
 928                         if (!port->bulk_in_buffers[j]) {
 929                                 dev_err(ddev, "Couldn't allocate bulk_in_buffer\n");
 930                                 goto probe_error;
 931                         }
 932                         usb_fill_bulk_urb(port->read_urbs[j], dev,
 933                                         usb_rcvbulkpipe(dev,
 934                                                 endpoint->bEndpointAddress),
 935                                         port->bulk_in_buffers[j], buffer_size,
 936                                         serial->type->read_bulk_callback,
 937                                         port);
 938                 }
 939
 940                 port->read_urb = port->read_urbs[0];
 941                 port->bulk_in_buffer = port->bulk_in_buffers[0];
 942         }
 943
 944         for (i = 0; i < num_bulk_out; ++i) {
 945                 endpoint = bulk_out_endpoint[i];
 946                 port = serial->port[i];
 947                 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 948                         goto probe_error;
 949                 buffer_size = serial->type->bulk_out_size;
 950                 if (!buffer_size)
 951                         buffer_size = usb_endpoint_maxp(endpoint);
 952                 port->bulk_out_size = buffer_size;
 953                 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
 954
 955                 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
 956                         set_bit(j, &port->write_urbs_free);
 957                         port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
 958                         if (!port->write_urbs[j]) {
 959                                 dev_err(ddev, "No free urbs available\n");
 960                                 goto probe_error;
 961                         }
 962                         port->bulk_out_buffers[j] = kmalloc(buffer_size,
 963                                                                 GFP_KERNEL);
 964                         if (!port->bulk_out_buffers[j]) {
 965                                 dev_err(ddev, "Couldn't allocate bulk_out_buffer\n");
 966                                 goto probe_error;
 967                         }
 968                         usb_fill_bulk_urb(port->write_urbs[j], dev,
 969                                         usb_sndbulkpipe(dev,
 970                                                 endpoint->bEndpointAddress),
 971                                         port->bulk_out_buffers[j], buffer_size,
 972                                         serial->type->write_bulk_callback,
 973                                         port);
 974                 }
 975
 976                 port->write_urb = port->write_urbs[0];
 977                 port->bulk_out_buffer = port->bulk_out_buffers[0];
 978         }
 979
 980         if (serial->type->read_int_callback) {
 981                 for (i = 0; i < num_interrupt_in; ++i) {
 982                         endpoint = interrupt_in_endpoint[i];
 983                         port = serial->port[i];
 984                         port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 985                         if (!port->interrupt_in_urb) {
 986                                 dev_err(ddev, "No free urbs available\n");
 987                                 goto probe_error;
 988                         }
 989                         buffer_size = usb_endpoint_maxp(endpoint);
 990                         port->interrupt_in_endpointAddress =
 991                                                 endpoint->bEndpointAddress;
 992                         port->interrupt_in_buffer = kmalloc(buffer_size,
 993                                                                 GFP_KERNEL);
 994                         if (!port->interrupt_in_buffer) {
 995                                 dev_err(ddev, "Couldn't allocate interrupt_in_buffer\n");
 996                                 goto probe_error;
 997                         }
 998                         usb_fill_int_urb(port->interrupt_in_urb, dev,
 999                                 usb_rcvintpipe(dev,
1000                                                 endpoint->bEndpointAddress),
1001                                 port->interrupt_in_buffer, buffer_size,
1002                                 serial->type->read_int_callback, port,
1003                                 endpoint->bInterval);
1004                 }
1005         } else if (num_interrupt_in) {
1006                 dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1007         }
1008
1009         if (serial->type->write_int_callback) {
1010                 for (i = 0; i < num_interrupt_out; ++i) {
1011                         endpoint = interrupt_out_endpoint[i];
1012                         port = serial->port[i];
1013                         port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1014                         if (!port->interrupt_out_urb) {
1015                                 dev_err(ddev, "No free urbs available\n");
1016                                 goto probe_error;
1017                         }
1018                         buffer_size = usb_endpoint_maxp(endpoint);
1019                         port->interrupt_out_size = buffer_size;
1020                         port->interrupt_out_endpointAddress =
1021                                                 endpoint->bEndpointAddress;
1022                         port->interrupt_out_buffer = kmalloc(buffer_size,
1023                                                                 GFP_KERNEL);
1024                         if (!port->interrupt_out_buffer) {
1025                                 dev_err(ddev, "Couldn't allocate interrupt_out_buffer\n");
1026                                 goto probe_error;
1027                         }
1028                         usb_fill_int_urb(port->interrupt_out_urb, dev,
1029                                 usb_sndintpipe(dev,
1030                                                   endpoint->bEndpointAddress),
1031                                 port->interrupt_out_buffer, buffer_size,
1032                                 serial->type->write_int_callback, port,
1033                                 endpoint->bInterval);
1034                 }
1035         } else if (num_interrupt_out) {
1036                 dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1037         }
1038
1039         usb_set_intfdata(interface, serial);
1040
1041         /* if this device type has an attach function, call it */
1042         if (type->attach) {
1043                 retval = type->attach(serial);
1044                 if (retval < 0)
1045                         goto probe_error;
1046                 serial->attached = 1;
1047                 if (retval > 0) {
1048                         /* quietly accept this device, but don't bind to a
1049                            serial port as it's about to disappear */
1050                         serial->num_ports = 0;
1051                         goto exit;
1052                 }
1053         } else {
1054                 serial->attached = 1;
1055         }
1056
1057         /* Avoid race with tty_open and serial_install by setting the
1058          * disconnected flag and not clearing it until all ports have been
1059          * registered.
1060          */
1061         serial->disconnected = 1;
1062
1063         if (get_free_serial(serial, num_ports, &minor) == NULL) {
1064                 dev_err(ddev, "No more free serial devices\n");
1065                 goto probe_error;
1066         }
1067         serial->minor = minor;
1068
1069         /* register all of the individual ports with the driver core */
1070         for (i = 0; i < num_ports; ++i) {
1071                 port = serial->port[i];
1072                 dev_set_name(&port->dev, "ttyUSB%d", port->number);
1073                 dev_dbg(ddev, "registering %s", dev_name(&port->dev));
1074                 device_enable_async_suspend(&port->dev);
1075
1076                 retval = device_add(&port->dev);
1077                 if (retval)
1078                         dev_err(ddev, "Error registering port device, continuing\n");
1079         }
1080
1081         serial->disconnected = 0;
1082
1083         usb_serial_console_init(minor);
1084 exit:
1085         module_put(type->driver.owner);
1086         return 0;
1087
1088 probe_error:
1089         usb_serial_put(serial);
1090         module_put(type->driver.owner);
1091         return -EIO;
1092 }
1093
1094 static void usb_serial_disconnect(struct usb_interface *interface)
1095 {
1096         int i;
1097         struct usb_serial *serial = usb_get_intfdata(interface);
1098         struct device *dev = &interface->dev;
1099         struct usb_serial_port *port;
1100
1101         usb_serial_console_disconnect(serial);
1102
1103         mutex_lock(&serial->disc_mutex);
1104         /* must set a flag, to signal subdrivers */
1105         serial->disconnected = 1;
1106         mutex_unlock(&serial->disc_mutex);
1107
1108         for (i = 0; i < serial->num_ports; ++i) {
1109                 port = serial->port[i];
1110                 if (port) {
1111                         struct tty_struct *tty = tty_port_tty_get(&port->port);
1112                         if (tty) {
1113                                 tty_vhangup(tty);
1114                                 tty_kref_put(tty);
1115                         }
1116                         kill_traffic(port);
1117                         cancel_work_sync(&port->work);
1118                         if (device_is_registered(&port->dev))
1119                                 device_del(&port->dev);
1120                 }
1121         }
1122         serial->type->disconnect(serial);
1123
1124         /* let the last holder of this object cause it to be cleaned up */
1125         usb_serial_put(serial);
1126         dev_info(dev, "device disconnected\n");
1127 }
1128
1129 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1130 {
1131         struct usb_serial *serial = usb_get_intfdata(intf);
1132         struct usb_serial_port *port;
1133         int i, r = 0;
1134
1135         serial->suspending = 1;
1136
1137         if (serial->type->suspend) {
1138                 r = serial->type->suspend(serial, message);
1139                 if (r < 0) {
1140                         serial->suspending = 0;
1141                         goto err_out;
1142                 }
1143         }
1144
1145         for (i = 0; i < serial->num_ports; ++i) {
1146                 port = serial->port[i];
1147                 if (port)
1148                         kill_traffic(port);
1149         }
1150
1151 err_out:
1152         return r;
1153 }
1154 EXPORT_SYMBOL(usb_serial_suspend);
1155
1156 int usb_serial_resume(struct usb_interface *intf)
1157 {
1158         struct usb_serial *serial = usb_get_intfdata(intf);
1159         int rv;
1160
1161         serial->suspending = 0;
1162         if (serial->type->resume)
1163                 rv = serial->type->resume(serial);
1164         else
1165                 rv = usb_serial_generic_resume(serial);
1166
1167         return rv;
1168 }
1169 EXPORT_SYMBOL(usb_serial_resume);
1170
1171 static int usb_serial_reset_resume(struct usb_interface *intf)
1172 {
1173         struct usb_serial *serial = usb_get_intfdata(intf);
1174         int rv;
1175
1176         serial->suspending = 0;
1177         if (serial->type->reset_resume)
1178                 rv = serial->type->reset_resume(serial);
1179         else {
1180                 rv = -EOPNOTSUPP;
1181                 intf->needs_binding = 1;
1182         }
1183
1184         return rv;
1185 }
1186
1187 static const struct tty_operations serial_ops = {
1188         .open =                 serial_open,
1189         .close =                serial_close,
1190         .write =                serial_write,
1191         .hangup =               serial_hangup,
1192         .write_room =           serial_write_room,
1193         .ioctl =                serial_ioctl,
1194         .set_termios =          serial_set_termios,
1195         .throttle =             serial_throttle,
1196         .unthrottle =           serial_unthrottle,
1197         .break_ctl =            serial_break,
1198         .chars_in_buffer =      serial_chars_in_buffer,
1199         .tiocmget =             serial_tiocmget,
1200         .tiocmset =             serial_tiocmset,
1201         .get_icount =           serial_get_icount,
1202         .cleanup =              serial_cleanup,
1203         .install =              serial_install,
1204         .proc_fops =            &serial_proc_fops,
1205 };
1206
1207
1208 struct tty_driver *usb_serial_tty_driver;
1209
1210 /* Driver structure we register with the USB core */
1211 static struct usb_driver usb_serial_driver = {
1212         .name =         "usbserial",
1213         .probe =        usb_serial_probe,
1214         .disconnect =   usb_serial_disconnect,
1215         .suspend =      usb_serial_suspend,
1216         .resume =       usb_serial_resume,
1217         .no_dynamic_id =        1,
1218         .supports_autosuspend = 1,
1219 };
1220
1221 static int __init usb_serial_init(void)
1222 {
1223         int i;
1224         int result;
1225
1226         usb_serial_tty_driver = alloc_tty_driver(SERIAL_TTY_MINORS);
1227         if (!usb_serial_tty_driver)
1228                 return -ENOMEM;
1229
1230         /* Initialize our global data */
1231         for (i = 0; i < SERIAL_TTY_MINORS; ++i)
1232                 serial_table[i] = NULL;
1233
1234         result = bus_register(&usb_serial_bus_type);
1235         if (result) {
1236                 pr_err("%s - registering bus driver failed\n", __func__);
1237                 goto exit_bus;
1238         }
1239
1240         usb_serial_tty_driver->driver_name = "usbserial";
1241         usb_serial_tty_driver->name = "ttyUSB";
1242         usb_serial_tty_driver->major = SERIAL_TTY_MAJOR;
1243         usb_serial_tty_driver->minor_start = 0;
1244         usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1245         usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1246         usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1247                                                 TTY_DRIVER_DYNAMIC_DEV;
1248         usb_serial_tty_driver->init_termios = tty_std_termios;
1249         usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1250                                                         | HUPCL | CLOCAL;
1251         usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1252         usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1253         tty_set_operations(usb_serial_tty_driver, &serial_ops);
1254         result = tty_register_driver(usb_serial_tty_driver);
1255         if (result) {
1256                 pr_err("%s - tty_register_driver failed\n", __func__);
1257                 goto exit_reg_driver;
1258         }
1259
1260         /* register the USB driver */
1261         result = usb_register(&usb_serial_driver);
1262         if (result < 0) {
1263                 pr_err("%s - usb_register failed\n", __func__);
1264                 goto exit_tty;
1265         }
1266
1267         /* register the generic driver, if we should */
1268         result = usb_serial_generic_register();
1269         if (result < 0) {
1270                 pr_err("%s - registering generic driver failed\n", __func__);
1271                 goto exit_generic;
1272         }
1273
1274         return result;
1275
1276 exit_generic:
1277         usb_deregister(&usb_serial_driver);
1278
1279 exit_tty:
1280         tty_unregister_driver(usb_serial_tty_driver);
1281
1282 exit_reg_driver:
1283         bus_unregister(&usb_serial_bus_type);
1284
1285 exit_bus:
1286         pr_err("%s - returning with error %d\n", __func__, result);
1287         put_tty_driver(usb_serial_tty_driver);
1288         return result;
1289 }
1290
1291
1292 static void __exit usb_serial_exit(void)
1293 {
1294         usb_serial_console_exit();
1295
1296         usb_serial_generic_deregister();
1297
1298         usb_deregister(&usb_serial_driver);
1299         tty_unregister_driver(usb_serial_tty_driver);
1300         put_tty_driver(usb_serial_tty_driver);
1301         bus_unregister(&usb_serial_bus_type);
1302 }
1303
1304
1305 module_init(usb_serial_init);
1306 module_exit(usb_serial_exit);
1307
1308 #define set_to_generic_if_null(type, function)                          \
1309         do {                                                            \
1310                 if (!type->function) {                                  \
1311                         type->function = usb_serial_generic_##function; \
1312                         pr_debug("Had to override the " #function       \
1313                                 " usb serial operation with the generic one.");\
1314                         }                                               \
1315         } while (0)
1316
1317 static void fixup_generic(struct usb_serial_driver *device)
1318 {
1319         set_to_generic_if_null(device, open);
1320         set_to_generic_if_null(device, write);
1321         set_to_generic_if_null(device, close);
1322         set_to_generic_if_null(device, write_room);
1323         set_to_generic_if_null(device, chars_in_buffer);
1324         set_to_generic_if_null(device, read_bulk_callback);
1325         set_to_generic_if_null(device, write_bulk_callback);
1326         set_to_generic_if_null(device, disconnect);
1327         set_to_generic_if_null(device, release);
1328         set_to_generic_if_null(device, process_read_urb);
1329         set_to_generic_if_null(device, prepare_write_buffer);
1330 }
1331
1332 static int usb_serial_register(struct usb_serial_driver *driver)
1333 {
1334         int retval;
1335
1336         if (usb_disabled())
1337                 return -ENODEV;
1338
1339         fixup_generic(driver);
1340
1341         if (!driver->description)
1342                 driver->description = driver->driver.name;
1343         if (!driver->usb_driver) {
1344                 WARN(1, "Serial driver %s has no usb_driver\n",
1345                                 driver->description);
1346                 return -EINVAL;
1347         }
1348
1349         /* Add this device to our list of devices */
1350         mutex_lock(&table_lock);
1351         list_add(&driver->driver_list, &usb_serial_driver_list);
1352
1353         retval = usb_serial_bus_register(driver);
1354         if (retval) {
1355                 pr_err("problem %d when registering driver %s\n", retval, driver->description);
1356                 list_del(&driver->driver_list);
1357         } else
1358                 pr_info("USB Serial support registered for %s\n", driver->description);
1359
1360         mutex_unlock(&table_lock);
1361         return retval;
1362 }
1363
1364 static void usb_serial_deregister(struct usb_serial_driver *device)
1365 {
1366         pr_info("USB Serial deregistering driver %s\n", device->description);
1367         mutex_lock(&table_lock);
1368         list_del(&device->driver_list);
1369         usb_serial_bus_deregister(device);
1370         mutex_unlock(&table_lock);
1371 }
1372
1373 /**
1374  * usb_serial_register_drivers - register drivers for a usb-serial module
1375  * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
1376  * @name: name of the usb_driver for this set of @serial_drivers
1377  * @id_table: list of all devices this @serial_drivers set binds to
1378  *
1379  * Registers all the drivers in the @serial_drivers array, and dynamically
1380  * creates a struct usb_driver with the name @name and id_table of @id_table.
1381  */
1382 int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1383                                 const char *name,
1384                                 const struct usb_device_id *id_table)
1385 {
1386         int rc;
1387         struct usb_driver *udriver;
1388         struct usb_serial_driver * const *sd;
1389
1390         /*
1391          * udriver must be registered before any of the serial drivers,
1392          * because the store_new_id() routine for the serial drivers (in
1393          * bus.c) probes udriver.
1394          *
1395          * Performance hack: We don't want udriver to be probed until
1396          * the serial drivers are registered, because the probe would
1397          * simply fail for lack of a matching serial driver.
1398          * So we leave udriver's id_table set to NULL until we are all set.
1399          *
1400          * Suspend/resume support is implemented in the usb-serial core,
1401          * so fill in the PM-related fields in udriver.
1402          */
1403         udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1404         if (!udriver)
1405                 return -ENOMEM;
1406
1407         udriver->name = name;
1408         udriver->no_dynamic_id = 1;
1409         udriver->supports_autosuspend = 1;
1410         udriver->suspend = usb_serial_suspend;
1411         udriver->resume = usb_serial_resume;
1412         udriver->probe = usb_serial_probe;
1413         udriver->disconnect = usb_serial_disconnect;
1414
1415         /* we only set the reset_resume field if the serial_driver has one */
1416         for (sd = serial_drivers; *sd; ++sd) {
1417                 if ((*sd)->reset_resume) {
1418                         udriver->reset_resume = usb_serial_reset_resume;
1419                         break;
1420                 }
1421         }
1422
1423         rc = usb_register(udriver);
1424         if (rc)
1425                 return rc;
1426
1427         for (sd = serial_drivers; *sd; ++sd) {
1428                 (*sd)->usb_driver = udriver;
1429                 rc = usb_serial_register(*sd);
1430                 if (rc)
1431                         goto failed;
1432         }
1433
1434         /* Now set udriver's id_table and look for matches */
1435         udriver->id_table = id_table;
1436         rc = driver_attach(&udriver->drvwrap.driver);
1437         return 0;
1438
1439  failed:
1440         while (sd-- > serial_drivers)
1441                 usb_serial_deregister(*sd);
1442         usb_deregister(udriver);
1443         return rc;
1444 }
1445 EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1446
1447 /**
1448  * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1449  * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1450  *
1451  * Deregisters all the drivers in the @serial_drivers array and deregisters and
1452  * frees the struct usb_driver that was created by the call to
1453  * usb_serial_register_drivers().
1454  */
1455 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1456 {
1457         struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1458
1459         for (; *serial_drivers; ++serial_drivers)
1460                 usb_serial_deregister(*serial_drivers);
1461         usb_deregister(udriver);
1462         kfree(udriver);
1463 }
1464 EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1465
1466 /* Module information */
1467 MODULE_AUTHOR(DRIVER_AUTHOR);
1468 MODULE_DESCRIPTION(DRIVER_DESC);
1469 MODULE_LICENSE("GPL");