drivers/usb/class/cdc-acm.c

   1 /*
   2  * cdc-acm.c
   3  *
   4  * Copyright (c) 1999 Armin Fuerst      <fuerst@in.tum.de>
   5  * Copyright (c) 1999 Pavel Machek      <pavel@ucw.cz>
   6  * Copyright (c) 1999 Johannes Erdfelt  <johannes@erdfelt.com>
   7  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
   8  * Copyright (c) 2004 Oliver Neukum     <oliver@neukum.name>
   9  * Copyright (c) 2005 David Kubicek     <dave@awk.cz>
  10  * Copyright (c) 2011 Johan Hovold      <jhovold@gmail.com>
  11  *
  12  * USB Abstract Control Model driver for USB modems and ISDN adapters
  13  *
  14  * Sponsored by SuSE
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  29  */
  30
  31 #undef DEBUG
  32 #undef VERBOSE_DEBUG
  33
  34 #include <linux/kernel.h>
  35 #include <linux/errno.h>
  36 #include <linux/init.h>
  37 #include <linux/slab.h>
  38 #include <linux/tty.h>
  39 #include <linux/serial.h>
  40 #include <linux/tty_driver.h>
  41 #include <linux/tty_flip.h>
  42 #include <linux/module.h>
  43 #include <linux/mutex.h>
  44 #include <linux/uaccess.h>
  45 #include <linux/usb.h>
  46 #include <linux/usb/cdc.h>
  47 #include <asm/byteorder.h>
  48 #include <asm/unaligned.h>
  49 #include <linux/list.h>
  50
  51 #include "cdc-acm.h"
  52
  53
  54 #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
  55 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
  56
  57 static struct usb_driver acm_driver;
  58 static struct tty_driver *acm_tty_driver;
  59 static struct acm *acm_table[ACM_TTY_MINORS];
  60
  61 static DEFINE_MUTEX(open_mutex);
  62
  63 #define ACM_READY(acm)  (acm && acm->dev && acm->port.count)
  64
  65 static const struct tty_port_operations acm_port_ops = {
  66 };
  67
  68 /*
  69  * Functions for ACM control messages.
  70  */
  71
  72 static int acm_ctrl_msg(struct acm *acm, int request, int value,
  73                                                         void *buf, int len)
  74 {
  75         int retval;
  76
  77         retval = usb_autopm_get_interface(acm->control);
  78         if (retval)
  79                 return retval;
  80
  81         retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
  82                 request, USB_RT_ACM, value,
  83                 acm->control->altsetting[0].desc.bInterfaceNumber,
  84                 buf, len, 5000);
  85
  86         dev_dbg(&acm->control->dev,
  87                         "%s - rq 0x%02x, val %#x, len %#x, result %d\n",
  88                         __func__, request, value, len, retval);
  89
  90         usb_autopm_put_interface(acm->control);
  91
  92         return retval < 0 ? retval : 0;
  93 }
  94
  95 /* devices aren't required to support these requests.
  96  * the cdc acm descriptor tells whether they do...
  97  */
  98 #define acm_set_control(acm, control) \
  99         acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, control, NULL, 0)
 100 #define acm_set_line(acm, line) \
 101         acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
 102 #define acm_send_break(acm, ms) \
 103         acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
 104
 105 /*
 106  * Write buffer management.
 107  * All of these assume proper locks taken by the caller.
 108  */
 109
 110 static int acm_wb_alloc(struct acm *acm)
 111 {
 112         int i, wbn;
 113         struct acm_wb *wb;
 114
 115         wbn = 0;
 116         i = 0;
 117         for (;;) {
 118                 wb = &acm->wb[wbn];
 119                 if (!wb->use) {
 120                         wb->use = 1;
 121                         return wbn;
 122                 }
 123                 wbn = (wbn + 1) % ACM_NW;
 124                 if (++i >= ACM_NW)
 125                         return -1;
 126         }
 127 }
 128
 129 static int acm_wb_is_avail(struct acm *acm)
 130 {
 131         int i, n;
 132         unsigned long flags;
 133
 134         n = ACM_NW;
 135         spin_lock_irqsave(&acm->write_lock, flags);
 136         for (i = 0; i < ACM_NW; i++)
 137                 n -= acm->wb[i].use;
 138         spin_unlock_irqrestore(&acm->write_lock, flags);
 139         return n;
 140 }
 141
 142 /*
 143  * Finish write. Caller must hold acm->write_lock
 144  */
 145 static void acm_write_done(struct acm *acm, struct acm_wb *wb)
 146 {
 147         wb->use = 0;
 148         acm->transmitting--;
 149         usb_autopm_put_interface_async(acm->control);
 150 }
 151
 152 /*
 153  * Poke write.
 154  *
 155  * the caller is responsible for locking
 156  */
 157
 158 static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
 159 {
 160         int rc;
 161
 162         acm->transmitting++;
 163
 164         wb->urb->transfer_buffer = wb->buf;
 165         wb->urb->transfer_dma = wb->dmah;
 166         wb->urb->transfer_buffer_length = wb->len;
 167         wb->urb->dev = acm->dev;
 168
 169         rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
 170         if (rc < 0) {
 171                 dev_err(&acm->data->dev,
 172                         "%s - usb_submit_urb(write bulk) failed: %d\n",
 173                         __func__, rc);
 174                 acm_write_done(acm, wb);
 175         }
 176         return rc;
 177 }
 178
 179 static int acm_write_start(struct acm *acm, int wbn)
 180 {
 181         unsigned long flags;
 182         struct acm_wb *wb = &acm->wb[wbn];
 183         int rc;
 184
 185         spin_lock_irqsave(&acm->write_lock, flags);
 186         if (!acm->dev) {
 187                 wb->use = 0;
 188                 spin_unlock_irqrestore(&acm->write_lock, flags);
 189                 return -ENODEV;
 190         }
 191
 192         dev_vdbg(&acm->data->dev, "%s - susp_count %d\n", __func__,
 193                                                         acm->susp_count);
 194         rc = usb_autopm_get_interface_async(acm->control);
 195         if (rc) {
 196                 wb->use = 0;
 197                 spin_unlock_irqrestore(&acm->write_lock, flags);
 198                 return rc;
 199         }
 200
 201         if (acm->susp_count) {
 202                 usb_anchor_urb(wb->urb, &acm->delayed);
 203                 spin_unlock_irqrestore(&acm->write_lock, flags);
 204                 return 0;
 205         }
 206         usb_mark_last_busy(acm->dev);
 207
 208         rc = acm_start_wb(acm, wb);
 209         spin_unlock_irqrestore(&acm->write_lock, flags);
 210
 211         return rc;
 212
 213 }
 214 /*
 215  * attributes exported through sysfs
 216  */
 217 static ssize_t show_caps
 218 (struct device *dev, struct device_attribute *attr, char *buf)
 219 {
 220         struct usb_interface *intf = to_usb_interface(dev);
 221         struct acm *acm = usb_get_intfdata(intf);
 222
 223         return sprintf(buf, "%d", acm->ctrl_caps);
 224 }
 225 static DEVICE_ATTR(bmCapabilities, S_IRUGO, show_caps, NULL);
 226
 227 static ssize_t show_country_codes
 228 (struct device *dev, struct device_attribute *attr, char *buf)
 229 {
 230         struct usb_interface *intf = to_usb_interface(dev);
 231         struct acm *acm = usb_get_intfdata(intf);
 232
 233         memcpy(buf, acm->country_codes, acm->country_code_size);
 234         return acm->country_code_size;
 235 }
 236
 237 static DEVICE_ATTR(wCountryCodes, S_IRUGO, show_country_codes, NULL);
 238
 239 static ssize_t show_country_rel_date
 240 (struct device *dev, struct device_attribute *attr, char *buf)
 241 {
 242         struct usb_interface *intf = to_usb_interface(dev);
 243         struct acm *acm = usb_get_intfdata(intf);
 244
 245         return sprintf(buf, "%d", acm->country_rel_date);
 246 }
 247
 248 static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL);
 249 /*
 250  * Interrupt handlers for various ACM device responses
 251  */
 252
 253 /* control interface reports status changes with "interrupt" transfers */
 254 static void acm_ctrl_irq(struct urb *urb)
 255 {
 256         struct acm *acm = urb->context;
 257         struct usb_cdc_notification *dr = urb->transfer_buffer;
 258         struct tty_struct *tty;
 259         unsigned char *data;
 260         int newctrl;
 261         int retval;
 262         int status = urb->status;
 263
 264         switch (status) {
 265         case 0:
 266                 /* success */
 267                 break;
 268         case -ECONNRESET:
 269         case -ENOENT:
 270         case -ESHUTDOWN:
 271                 /* this urb is terminated, clean up */
 272                 dev_dbg(&acm->control->dev,
 273                                 "%s - urb shutting down with status: %d\n",
 274                                 __func__, status);
 275                 return;
 276         default:
 277                 dev_dbg(&acm->control->dev,
 278                                 "%s - nonzero urb status received: %d\n",
 279                                 __func__, status);
 280                 goto exit;
 281         }
 282
 283         if (!ACM_READY(acm))
 284                 goto exit;
 285
 286         usb_mark_last_busy(acm->dev);
 287
 288         data = (unsigned char *)(dr + 1);
 289         switch (dr->bNotificationType) {
 290         case USB_CDC_NOTIFY_NETWORK_CONNECTION:
 291                 dev_dbg(&acm->control->dev, "%s - network connection: %d\n",
 292                                                         __func__, dr->wValue);
 293                 break;
 294
 295         case USB_CDC_NOTIFY_SERIAL_STATE:
 296                 tty = tty_port_tty_get(&acm->port);
 297                 newctrl = get_unaligned_le16(data);
 298
 299                 if (tty) {
 300                         if (!acm->clocal &&
 301                                 (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
 302                                 dev_dbg(&acm->control->dev,
 303                                         "%s - calling hangup\n", __func__);
 304                                 tty_hangup(tty);
 305                         }
 306                         tty_kref_put(tty);
 307                 }
 308
 309                 acm->ctrlin = newctrl;
 310
 311                 dev_dbg(&acm->control->dev,
 312                         "%s - input control lines: dcd%c dsr%c break%c "
 313                         "ring%c framing%c parity%c overrun%c\n",
 314                         __func__,
 315                         acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',
 316                         acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
 317                         acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',
 318                         acm->ctrlin & ACM_CTRL_RI  ? '+' : '-',
 319                         acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-',
 320                         acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',
 321                         acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');
 322                         break;
 323
 324         default:
 325                 dev_dbg(&acm->control->dev,
 326                         "%s - unknown notification %d received: index %d "
 327                         "len %d data0 %d data1 %d\n",
 328                         __func__,
 329                         dr->bNotificationType, dr->wIndex,
 330                         dr->wLength, data[0], data[1]);
 331                 break;
 332         }
 333 exit:
 334         retval = usb_submit_urb(urb, GFP_ATOMIC);
 335         if (retval)
 336                 dev_err(&acm->control->dev, "%s - usb_submit_urb failed: %d\n",
 337                                                         __func__, retval);
 338 }
 339
 340 static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
 341 {
 342         int res;
 343
 344         if (!test_and_clear_bit(index, &acm->read_urbs_free))
 345                 return 0;
 346
 347         dev_vdbg(&acm->data->dev, "%s - urb %d\n", __func__, index);
 348
 349         res = usb_submit_urb(acm->read_urbs[index], mem_flags);
 350         if (res) {
 351                 if (res != -EPERM) {
 352                         dev_err(&acm->data->dev,
 353                                         "%s - usb_submit_urb failed: %d\n",
 354                                         __func__, res);
 355                 }
 356                 set_bit(index, &acm->read_urbs_free);
 357                 return res;
 358         }
 359
 360         return 0;
 361 }
 362
 363 static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
 364 {
 365         int res;
 366         int i;
 367
 368         for (i = 0; i < acm->rx_buflimit; ++i) {
 369                 res = acm_submit_read_urb(acm, i, mem_flags);
 370                 if (res)
 371                         return res;
 372         }
 373
 374         return 0;
 375 }
 376
 377 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
 378 {
 379         struct tty_struct *tty;
 380
 381         if (!urb->actual_length)
 382                 return;
 383
 384         tty = tty_port_tty_get(&acm->port);
 385         if (!tty)
 386                 return;
 387
 388         tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
 389         tty_flip_buffer_push(tty);
 390
 391         tty_kref_put(tty);
 392 }
 393
 394 static void acm_read_bulk_callback(struct urb *urb)
 395 {
 396         struct acm_rb *rb = urb->context;
 397         struct acm *acm = rb->instance;
 398         unsigned long flags;
 399
 400         dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
 401                                         rb->index, urb->actual_length);
 402         set_bit(rb->index, &acm->read_urbs_free);
 403
 404         if (!acm->dev) {
 405                 dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
 406                 return;
 407         }
 408         usb_mark_last_busy(acm->dev);
 409
 410         if (urb->status) {
 411                 dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
 412                                                         __func__, urb->status);
 413                 return;
 414         }
 415         acm_process_read_urb(acm, urb);
 416
 417         /* throttle device if requested by tty */
 418         spin_lock_irqsave(&acm->read_lock, flags);
 419         acm->throttled = acm->throttle_req;
 420         if (!acm->throttled && !acm->susp_count) {
 421                 spin_unlock_irqrestore(&acm->read_lock, flags);
 422                 acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
 423         } else {
 424                 spin_unlock_irqrestore(&acm->read_lock, flags);
 425         }
 426 }
 427
 428 /* data interface wrote those outgoing bytes */
 429 static void acm_write_bulk(struct urb *urb)
 430 {
 431         struct acm_wb *wb = urb->context;
 432         struct acm *acm = wb->instance;
 433         unsigned long flags;
 434
 435         if (urb->status || (urb->actual_length != urb->transfer_buffer_length))
 436                 dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
 437                         __func__,
 438                         urb->actual_length,
 439                         urb->transfer_buffer_length,
 440                         urb->status);
 441
 442         spin_lock_irqsave(&acm->write_lock, flags);
 443         acm_write_done(acm, wb);
 444         spin_unlock_irqrestore(&acm->write_lock, flags);
 445         if (ACM_READY(acm))
 446                 schedule_work(&acm->work);
 447 }
 448
 449 static void acm_softint(struct work_struct *work)
 450 {
 451         struct acm *acm = container_of(work, struct acm, work);
 452         struct tty_struct *tty;
 453
 454         dev_vdbg(&acm->data->dev, "%s\n", __func__);
 455
 456         if (!ACM_READY(acm))
 457                 return;
 458         tty = tty_port_tty_get(&acm->port);
 459         if (!tty)
 460                 return;
 461         tty_wakeup(tty);
 462         tty_kref_put(tty);
 463 }
 464
 465 /*
 466  * TTY handlers
 467  */
 468
 469 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 470 {
 471         struct acm *acm;
 472         int rv = -ENODEV;
 473
 474         mutex_lock(&open_mutex);
 475
 476         acm = acm_table[tty->index];
 477         if (!acm || !acm->dev)
 478                 goto out;
 479         else
 480                 rv = 0;
 481
 482         dev_dbg(&acm->control->dev, "%s\n", __func__);
 483
 484         set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
 485
 486         tty->driver_data = acm;
 487         tty_port_tty_set(&acm->port, tty);
 488
 489         if (usb_autopm_get_interface(acm->control) < 0)
 490                 goto early_bail;
 491         else
 492                 acm->control->needs_remote_wakeup = 1;
 493
 494         mutex_lock(&acm->mutex);
 495         if (acm->port.count++) {
 496                 mutex_unlock(&acm->mutex);
 497                 usb_autopm_put_interface(acm->control);
 498                 goto out;
 499         }
 500
 501         acm->ctrlurb->dev = acm->dev;
 502         if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
 503                 dev_err(&acm->control->dev,
 504                         "%s - usb_submit_urb(ctrl irq) failed\n", __func__);
 505                 goto bail_out;
 506         }
 507
 508         if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) &&
 509             (acm->ctrl_caps & USB_CDC_CAP_LINE))
 510                 goto bail_out;
 511
 512         usb_autopm_put_interface(acm->control);
 513
 514         /*
 515          * Unthrottle device in case the TTY was closed while throttled.
 516          */
 517         spin_lock_irq(&acm->read_lock);
 518         acm->throttled = 0;
 519         acm->throttle_req = 0;
 520         spin_unlock_irq(&acm->read_lock);
 521
 522         if (acm_submit_read_urbs(acm, GFP_KERNEL))
 523                 goto bail_out;
 524
 525         set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
 526         rv = tty_port_block_til_ready(&acm->port, tty, filp);
 527
 528         mutex_unlock(&acm->mutex);
 529 out:
 530         mutex_unlock(&open_mutex);
 531         return rv;
 532
 533 bail_out:
 534         acm->port.count--;
 535         mutex_unlock(&acm->mutex);
 536         usb_autopm_put_interface(acm->control);
 537 early_bail:
 538         mutex_unlock(&open_mutex);
 539         tty_port_tty_set(&acm->port, NULL);
 540         return -EIO;
 541 }
 542
 543 static void acm_tty_unregister(struct acm *acm)
 544 {
 545         int i;
 546
 547         tty_unregister_device(acm_tty_driver, acm->minor);
 548         usb_put_intf(acm->control);
 549         acm_table[acm->minor] = NULL;
 550         usb_free_urb(acm->ctrlurb);
 551         for (i = 0; i < ACM_NW; i++)
 552                 usb_free_urb(acm->wb[i].urb);
 553         for (i = 0; i < acm->rx_buflimit; i++)
 554                 usb_free_urb(acm->read_urbs[i]);
 555         kfree(acm->country_codes);
 556         kfree(acm);
 557 }
 558
 559 static void acm_port_down(struct acm *acm)
 560 {
 561         struct urb *urb;
 562         struct acm_wb *wb;
 563         int i;
 564
 565         if (acm->dev) {
 566                 usb_autopm_get_interface(acm->control);
 567                 acm_set_control(acm, acm->ctrlout = 0);
 568
 569                 for (;;) {
 570                         urb = usb_get_from_anchor(&acm->delayed);
 571                         if (!urb)
 572                                 break;
 573                         wb = urb->context;
 574                         wb->use = 0;
 575                         usb_autopm_put_interface_async(acm->control);
 576                 }
 577
 578                 usb_kill_urb(acm->ctrlurb);
 579                 for (i = 0; i < ACM_NW; i++)
 580                         usb_kill_urb(acm->wb[i].urb);
 581                 for (i = 0; i < acm->rx_buflimit; i++)
 582                         usb_kill_urb(acm->read_urbs[i]);
 583                 acm->control->needs_remote_wakeup = 0;
 584                 usb_autopm_put_interface(acm->control);
 585         }
 586 }
 587
 588 static void acm_tty_hangup(struct tty_struct *tty)
 589 {
 590         struct acm *acm;
 591
 592         mutex_lock(&open_mutex);
 593         acm = tty->driver_data;
 594
 595         if (!acm)
 596                 goto out;
 597
 598         tty_port_hangup(&acm->port);
 599         acm_port_down(acm);
 600
 601 out:
 602         mutex_unlock(&open_mutex);
 603 }
 604
 605 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
 606 {
 607         struct acm *acm = tty->driver_data;
 608
 609         /* Perform the closing process and see if we need to do the hardware
 610            shutdown */
 611         if (!acm)
 612                 return;
 613
 614         mutex_lock(&open_mutex);
 615         if (tty_port_close_start(&acm->port, tty, filp) == 0) {
 616                 if (!acm->dev) {
 617                         tty_port_tty_set(&acm->port, NULL);
 618                         acm_tty_unregister(acm);
 619                         tty->driver_data = NULL;
 620                 }
 621                 mutex_unlock(&open_mutex);
 622                 return;
 623         }
 624         acm_port_down(acm);
 625         tty_port_close_end(&acm->port, tty);
 626         tty_port_tty_set(&acm->port, NULL);
 627         mutex_unlock(&open_mutex);
 628 }
 629
 630 static int acm_tty_write(struct tty_struct *tty,
 631                                         const unsigned char *buf, int count)
 632 {
 633         struct acm *acm = tty->driver_data;
 634         int stat;
 635         unsigned long flags;
 636         int wbn;
 637         struct acm_wb *wb;
 638
 639         if (!ACM_READY(acm))
 640                 return -EINVAL;
 641         if (!count)
 642                 return 0;
 643
 644         dev_vdbg(&acm->data->dev, "%s - count %d\n", __func__, count);
 645
 646         spin_lock_irqsave(&acm->write_lock, flags);
 647         wbn = acm_wb_alloc(acm);
 648         if (wbn < 0) {
 649                 spin_unlock_irqrestore(&acm->write_lock, flags);
 650                 return 0;
 651         }
 652         wb = &acm->wb[wbn];
 653
 654         count = (count > acm->writesize) ? acm->writesize : count;
 655         dev_vdbg(&acm->data->dev, "%s - write %d\n", __func__, count);
 656         memcpy(wb->buf, buf, count);
 657         wb->len = count;
 658         spin_unlock_irqrestore(&acm->write_lock, flags);
 659
 660         stat = acm_write_start(acm, wbn);
 661         if (stat < 0)
 662                 return stat;
 663         return count;
 664 }
 665
 666 static int acm_tty_write_room(struct tty_struct *tty)
 667 {
 668         struct acm *acm = tty->driver_data;
 669         if (!ACM_READY(acm))
 670                 return -EINVAL;
 671         /*
 672          * Do not let the line discipline to know that we have a reserve,
 673          * or it might get too enthusiastic.
 674          */
 675         return acm_wb_is_avail(acm) ? acm->writesize : 0;
 676 }
 677
 678 static int acm_tty_chars_in_buffer(struct tty_struct *tty)
 679 {
 680         struct acm *acm = tty->driver_data;
 681         if (!ACM_READY(acm))
 682                 return 0;
 683         /*
 684          * This is inaccurate (overcounts), but it works.
 685          */
 686         return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
 687 }
 688
 689 static void acm_tty_throttle(struct tty_struct *tty)
 690 {
 691         struct acm *acm = tty->driver_data;
 692
 693         if (!ACM_READY(acm))
 694                 return;
 695
 696         spin_lock_irq(&acm->read_lock);
 697         acm->throttle_req = 1;
 698         spin_unlock_irq(&acm->read_lock);
 699 }
 700
 701 static void acm_tty_unthrottle(struct tty_struct *tty)
 702 {
 703         struct acm *acm = tty->driver_data;
 704         unsigned int was_throttled;
 705
 706         if (!ACM_READY(acm))
 707                 return;
 708
 709         spin_lock_irq(&acm->read_lock);
 710         was_throttled = acm->throttled;
 711         acm->throttled = 0;
 712         acm->throttle_req = 0;
 713         spin_unlock_irq(&acm->read_lock);
 714
 715         if (was_throttled)
 716                 acm_submit_read_urbs(acm, GFP_KERNEL);
 717 }
 718
 719 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
 720 {
 721         struct acm *acm = tty->driver_data;
 722         int retval;
 723         if (!ACM_READY(acm))
 724                 return -EINVAL;
 725         retval = acm_send_break(acm, state ? 0xffff : 0);
 726         if (retval < 0)
 727                 dev_dbg(&acm->control->dev, "%s - send break failed\n",
 728                                                                 __func__);
 729         return retval;
 730 }
 731
 732 static int acm_tty_tiocmget(struct tty_struct *tty)
 733 {
 734         struct acm *acm = tty->driver_data;
 735
 736         if (!ACM_READY(acm))
 737                 return -EINVAL;
 738
 739         return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
 740                (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
 741                (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
 742                (acm->ctrlin  & ACM_CTRL_RI  ? TIOCM_RI  : 0) |
 743                (acm->ctrlin  & ACM_CTRL_DCD ? TIOCM_CD  : 0) |
 744                TIOCM_CTS;
 745 }
 746
 747 static int acm_tty_tiocmset(struct tty_struct *tty,
 748                             unsigned int set, unsigned int clear)
 749 {
 750         struct acm *acm = tty->driver_data;
 751         unsigned int newctrl;
 752
 753         if (!ACM_READY(acm))
 754                 return -EINVAL;
 755
 756         newctrl = acm->ctrlout;
 757         set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
 758                                         (set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
 759         clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
 760                                         (clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);
 761
 762         newctrl = (newctrl & ~clear) | set;
 763
 764         if (acm->ctrlout == newctrl)
 765                 return 0;
 766         return acm_set_control(acm, acm->ctrlout = newctrl);
 767 }
 768
 769 static int acm_tty_ioctl(struct tty_struct *tty,
 770                                         unsigned int cmd, unsigned long arg)
 771 {
 772         struct acm *acm = tty->driver_data;
 773
 774         if (!ACM_READY(acm))
 775                 return -EINVAL;
 776
 777         return -ENOIOCTLCMD;
 778 }
 779
 780 static const __u32 acm_tty_speed[] = {
 781         0, 50, 75, 110, 134, 150, 200, 300, 600,
 782         1200, 1800, 2400, 4800, 9600, 19200, 38400,
 783         57600, 115200, 230400, 460800, 500000, 576000,
 784         921600, 1000000, 1152000, 1500000, 2000000,
 785         2500000, 3000000, 3500000, 4000000
 786 };
 787
 788 static void acm_tty_set_termios(struct tty_struct *tty,
 789                                                 struct ktermios *termios_old)
 790 {
 791         struct acm *acm = tty->driver_data;
 792         struct ktermios *termios = tty->termios;
 793         struct usb_cdc_line_coding newline;
 794         int newctrl = acm->ctrlout;
 795
 796         if (!ACM_READY(acm))
 797                 return;
 798
 799         newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
 800         newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
 801         newline.bParityType = termios->c_cflag & PARENB ?
 802                                 (termios->c_cflag & PARODD ? 1 : 2) +
 803                                 (termios->c_cflag & CMSPAR ? 2 : 0) : 0;
 804         switch (termios->c_cflag & CSIZE) {
 805         case CS5:
 806                 newline.bDataBits = 5;
 807                 break;
 808         case CS6:
 809                 newline.bDataBits = 6;
 810                 break;
 811         case CS7:
 812                 newline.bDataBits = 7;
 813                 break;
 814         case CS8:
 815         default:
 816                 newline.bDataBits = 8;
 817                 break;
 818         }
 819         /* FIXME: Needs to clear unsupported bits in the termios */
 820         acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
 821
 822         if (C_BAUD(tty) == B0) {
 823                 newline.dwDTERate = acm->line.dwDTERate;
 824                 newctrl &= ~ACM_CTRL_DTR;
 825         } else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
 826                 newctrl |=  ACM_CTRL_DTR;
 827         }
 828
 829         if (newctrl != acm->ctrlout)
 830                 acm_set_control(acm, acm->ctrlout = newctrl);
 831
 832         if (memcmp(&acm->line, &newline, sizeof newline)) {
 833                 memcpy(&acm->line, &newline, sizeof newline);
 834                 dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
 835                         __func__,
 836                         le32_to_cpu(newline.dwDTERate),
 837                         newline.bCharFormat, newline.bParityType,
 838                         newline.bDataBits);
 839                 acm_set_line(acm, &acm->line);
 840         }
 841 }
 842
 843 /*
 844  * USB probe and disconnect routines.
 845  */
 846
 847 /* Little helpers: write/read buffers free */
 848 static void acm_write_buffers_free(struct acm *acm)
 849 {
 850         int i;
 851         struct acm_wb *wb;
 852         struct usb_device *usb_dev = interface_to_usbdev(acm->control);
 853
 854         for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
 855                 usb_free_coherent(usb_dev, acm->writesize, wb->buf, wb->dmah);
 856 }
 857
 858 static void acm_read_buffers_free(struct acm *acm)
 859 {
 860         struct usb_device *usb_dev = interface_to_usbdev(acm->control);
 861         int i;
 862
 863         for (i = 0; i < acm->rx_buflimit; i++)
 864                 usb_free_coherent(usb_dev, acm->readsize,
 865                           acm->read_buffers[i].base, acm->read_buffers[i].dma);
 866 }
 867
 868 /* Little helper: write buffers allocate */
 869 static int acm_write_buffers_alloc(struct acm *acm)
 870 {
 871         int i;
 872         struct acm_wb *wb;
 873
 874         for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
 875                 wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
 876                     &wb->dmah);
 877                 if (!wb->buf) {
 878                         while (i != 0) {
 879                                 --i;
 880                                 --wb;
 881                                 usb_free_coherent(acm->dev, acm->writesize,
 882                                     wb->buf, wb->dmah);
 883                         }
 884                         return -ENOMEM;
 885                 }
 886         }
 887         return 0;
 888 }
 889
 890 static int acm_probe(struct usb_interface *intf,
 891                      const struct usb_device_id *id)
 892 {
 893         struct usb_cdc_union_desc *union_header = NULL;
 894         struct usb_cdc_country_functional_desc *cfd = NULL;
 895         unsigned char *buffer = intf->altsetting->extra;
 896         int buflen = intf->altsetting->extralen;
 897         struct usb_interface *control_interface;
 898         struct usb_interface *data_interface;
 899         struct usb_endpoint_descriptor *epctrl = NULL;
 900         struct usb_endpoint_descriptor *epread = NULL;
 901         struct usb_endpoint_descriptor *epwrite = NULL;
 902         struct usb_device *usb_dev = interface_to_usbdev(intf);
 903         struct acm *acm;
 904         int minor;
 905         int ctrlsize, readsize;
 906         u8 *buf;
 907         u8 ac_management_function = 0;
 908         u8 call_management_function = 0;
 909         int call_interface_num = -1;
 910         int data_interface_num = -1;
 911         unsigned long quirks;
 912         int num_rx_buf;
 913         int i;
 914         int combined_interfaces = 0;
 915
 916         /* normal quirks */
 917         quirks = (unsigned long)id->driver_info;
 918         num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
 919
 920         /* handle quirks deadly to normal probing*/
 921         if (quirks == NO_UNION_NORMAL) {
 922                 data_interface = usb_ifnum_to_if(usb_dev, 1);
 923                 control_interface = usb_ifnum_to_if(usb_dev, 0);
 924                 goto skip_normal_probe;
 925         }
 926
 927         /* normal probing*/
 928         if (!buffer) {
 929                 dev_err(&intf->dev, "Weird descriptor references\n");
 930                 return -EINVAL;
 931         }
 932
 933         if (!buflen) {
 934                 if (intf->cur_altsetting->endpoint &&
 935                                 intf->cur_altsetting->endpoint->extralen &&
 936                                 intf->cur_altsetting->endpoint->extra) {
 937                         dev_dbg(&intf->dev,
 938                                 "Seeking extra descriptors on endpoint\n");
 939                         buflen = intf->cur_altsetting->endpoint->extralen;
 940                         buffer = intf->cur_altsetting->endpoint->extra;
 941                 } else {
 942                         dev_err(&intf->dev,
 943                                 "Zero length descriptor references\n");
 944                         return -EINVAL;
 945                 }
 946         }
 947
 948         while (buflen > 0) {
 949                 if (buffer[1] != USB_DT_CS_INTERFACE) {
 950                         dev_err(&intf->dev, "skipping garbage\n");
 951                         goto next_desc;
 952                 }
 953
 954                 switch (buffer[2]) {
 955                 case USB_CDC_UNION_TYPE: /* we've found it */
 956                         if (union_header) {
 957                                 dev_err(&intf->dev, "More than one "
 958                                         "union descriptor, skipping ...\n");
 959                                 goto next_desc;
 960                         }
 961                         union_header = (struct usb_cdc_union_desc *)buffer;
 962                         break;
 963                 case USB_CDC_COUNTRY_TYPE: /* export through sysfs*/
 964                         cfd = (struct usb_cdc_country_functional_desc *)buffer;
 965                         break;
 966                 case USB_CDC_HEADER_TYPE: /* maybe check version */
 967                         break; /* for now we ignore it */
 968                 case USB_CDC_ACM_TYPE:
 969                         ac_management_function = buffer[3];
 970                         break;
 971                 case USB_CDC_CALL_MANAGEMENT_TYPE:
 972                         call_management_function = buffer[3];
 973                         call_interface_num = buffer[4];
 974                         if ( (quirks & NOT_A_MODEM) == 0 && (call_management_function & 3) != 3)
 975                                 dev_err(&intf->dev, "This device cannot do calls on its own. It is not a modem.\n");
 976                         break;
 977                 default:
 978                         /* there are LOTS more CDC descriptors that
 979                          * could legitimately be found here.
 980                          */
 981                         dev_dbg(&intf->dev, "Ignoring descriptor: "
 982                                         "type %02x, length %d\n",
 983                                         buffer[2], buffer[0]);
 984                         break;
 985                 }
 986 next_desc:
 987                 buflen -= buffer[0];
 988                 buffer += buffer[0];
 989         }
 990
 991         if (!union_header) {
 992                 if (call_interface_num > 0) {
 993                         dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
 994                         /* quirks for Droids MuIn LCD */
 995                         if (quirks & NO_DATA_INTERFACE)
 996                                 data_interface = usb_ifnum_to_if(usb_dev, 0);
 997                         else
 998                                 data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
 999                         control_interface = intf;
1000                 } else {
1001                         if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
1002                                 dev_dbg(&intf->dev,"No union descriptor, giving up\n");
1003                                 return -ENODEV;
1004                         } else {
1005                                 dev_warn(&intf->dev,"No union descriptor, testing for castrated device\n");
1006                                 combined_interfaces = 1;
1007                                 control_interface = data_interface = intf;
1008                                 goto look_for_collapsed_interface;
1009                         }
1010                 }
1011         } else {
1012                 control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
1013                 data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
1014         }
1015
1016         if (!control_interface || !data_interface) {
1017                 dev_dbg(&intf->dev, "no interfaces\n");
1018                 return -ENODEV;
1019         }
1020
1021         if (data_interface_num != call_interface_num)
1022                 dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
1023
1024         if (control_interface == data_interface) {
1025                 /* some broken devices designed for windows work this way */
1026                 dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
1027                 combined_interfaces = 1;
1028                 /* a popular other OS doesn't use it */
1029                 quirks |= NO_CAP_LINE;
1030                 if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
1031                         dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
1032                         return -EINVAL;
1033                 }
1034 look_for_collapsed_interface:
1035                 for (i = 0; i < 3; i++) {
1036                         struct usb_endpoint_descriptor *ep;
1037                         ep = &data_interface->cur_altsetting->endpoint[i].desc;
1038
1039                         if (usb_endpoint_is_int_in(ep))
1040                                 epctrl = ep;
1041                         else if (usb_endpoint_is_bulk_out(ep))
1042                                 epwrite = ep;
1043                         else if (usb_endpoint_is_bulk_in(ep))
1044                                 epread = ep;
1045                         else
1046                                 return -EINVAL;
1047                 }
1048                 if (!epctrl || !epread || !epwrite)
1049                         return -ENODEV;
1050                 else
1051                         goto made_compressed_probe;
1052         }
1053
1054 skip_normal_probe:
1055
1056         /*workaround for switched interfaces */
1057         if (data_interface->cur_altsetting->desc.bInterfaceClass
1058                                                 != CDC_DATA_INTERFACE_TYPE) {
1059                 if (control_interface->cur_altsetting->desc.bInterfaceClass
1060                                                 == CDC_DATA_INTERFACE_TYPE) {
1061                         struct usb_interface *t;
1062                         dev_dbg(&intf->dev,
1063                                 "Your device has switched interfaces.\n");
1064                         t = control_interface;
1065                         control_interface = data_interface;
1066                         data_interface = t;
1067                 } else {
1068                         return -EINVAL;
1069                 }
1070         }
1071
1072         /* Accept probe requests only for the control interface */
1073         if (!combined_interfaces && intf != control_interface)
1074                 return -ENODEV;
1075
1076         if (!combined_interfaces && usb_interface_claimed(data_interface)) {
1077                 /* valid in this context */
1078                 dev_dbg(&intf->dev, "The data interface isn't available\n");
1079                 return -EBUSY;
1080         }
1081
1082
1083         if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
1084             control_interface->cur_altsetting->desc.bNumEndpoints == 0)
1085                 return -EINVAL;
1086
1087         epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
1088         epread = &data_interface->cur_altsetting->endpoint[0].desc;
1089         epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
1090
1091
1092         /* workaround for switched endpoints */
1093         if (!usb_endpoint_dir_in(epread)) {
1094                 /* descriptors are swapped */
1095                 struct usb_endpoint_descriptor *t;
1096                 dev_dbg(&intf->dev,
1097                         "The data interface has switched endpoints\n");
1098                 t = epread;
1099                 epread = epwrite;
1100                 epwrite = t;
1101         }
1102 made_compressed_probe:
1103         dev_dbg(&intf->dev, "interfaces are valid\n");
1104         for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
1105
1106         if (minor == ACM_TTY_MINORS) {
1107                 dev_err(&intf->dev, "no more free acm devices\n");
1108                 return -ENODEV;
1109         }
1110
1111         acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
1112         if (acm == NULL) {
1113                 dev_err(&intf->dev, "out of memory (acm kzalloc)\n");
1114                 goto alloc_fail;
1115         }
1116
1117         ctrlsize = usb_endpoint_maxp(epctrl);
1118         readsize = usb_endpoint_maxp(epread) *
1119                                 (quirks == SINGLE_RX_URB ? 1 : 2);
1120         acm->combined_interfaces = combined_interfaces;
1121         acm->writesize = usb_endpoint_maxp(epwrite) * 20;
1122         acm->control = control_interface;
1123         acm->data = data_interface;
1124         acm->minor = minor;
1125         acm->dev = usb_dev;
1126         acm->ctrl_caps = ac_management_function;
1127         if (quirks & NO_CAP_LINE)
1128                 acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1129         acm->ctrlsize = ctrlsize;
1130         acm->readsize = readsize;
1131         acm->rx_buflimit = num_rx_buf;
1132         INIT_WORK(&acm->work, acm_softint);
1133         spin_lock_init(&acm->write_lock);
1134         spin_lock_init(&acm->read_lock);
1135         mutex_init(&acm->mutex);
1136         acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
1137         acm->is_int_ep = usb_endpoint_xfer_int(epread);
1138         if (acm->is_int_ep)
1139                 acm->bInterval = epread->bInterval;
1140         tty_port_init(&acm->port);
1141         acm->port.ops = &acm_port_ops;
1142         init_usb_anchor(&acm->delayed);
1143
1144         buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
1145         if (!buf) {
1146                 dev_err(&intf->dev, "out of memory (ctrl buffer alloc)\n");
1147                 goto alloc_fail2;
1148         }
1149         acm->ctrl_buffer = buf;
1150
1151         if (acm_write_buffers_alloc(acm) < 0) {
1152                 dev_err(&intf->dev, "out of memory (write buffer alloc)\n");
1153                 goto alloc_fail4;
1154         }
1155
1156         acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
1157         if (!acm->ctrlurb) {
1158                 dev_err(&intf->dev, "out of memory (ctrlurb kmalloc)\n");
1159                 goto alloc_fail5;
1160         }
1161         for (i = 0; i < num_rx_buf; i++) {
1162                 struct acm_rb *rb = &(acm->read_buffers[i]);
1163                 struct urb *urb;
1164
1165                 rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
1166                                                                 &rb->dma);
1167                 if (!rb->base) {
1168                         dev_err(&intf->dev, "out of memory "
1169                                         "(read bufs usb_alloc_coherent)\n");
1170                         goto alloc_fail6;
1171                 }
1172                 rb->index = i;
1173                 rb->instance = acm;
1174
1175                 urb = usb_alloc_urb(0, GFP_KERNEL);
1176                 if (!urb) {
1177                         dev_err(&intf->dev,
1178                                 "out of memory (read urbs usb_alloc_urb)\n");
1179                         goto alloc_fail6;
1180                 }
1181                 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1182                 urb->transfer_dma = rb->dma;
1183                 if (acm->is_int_ep) {
1184                         usb_fill_int_urb(urb, acm->dev,
1185                                          acm->rx_endpoint,
1186                                          rb->base,
1187                                          acm->readsize,
1188                                          acm_read_bulk_callback, rb,
1189                                          acm->bInterval);
1190                 } else {
1191                         usb_fill_bulk_urb(urb, acm->dev,
1192                                           acm->rx_endpoint,
1193                                           rb->base,
1194                                           acm->readsize,
1195                                           acm_read_bulk_callback, rb);
1196                 }
1197
1198                 acm->read_urbs[i] = urb;
1199                 __set_bit(i, &acm->read_urbs_free);
1200         }
1201         for (i = 0; i < ACM_NW; i++) {
1202                 struct acm_wb *snd = &(acm->wb[i]);
1203
1204                 snd->urb = usb_alloc_urb(0, GFP_KERNEL);
1205                 if (snd->urb == NULL) {
1206                         dev_err(&intf->dev,
1207                                 "out of memory (write urbs usb_alloc_urb)\n");
1208                         goto alloc_fail7;
1209                 }
1210
1211                 if (usb_endpoint_xfer_int(epwrite))
1212                         usb_fill_int_urb(snd->urb, usb_dev,
1213                                 usb_sndintpipe(usb_dev, epwrite->bEndpointAddress),
1214                                 NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
1215                 else
1216                         usb_fill_bulk_urb(snd->urb, usb_dev,
1217                                 usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
1218                                 NULL, acm->writesize, acm_write_bulk, snd);
1219                 snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1220                 snd->instance = acm;
1221         }
1222
1223         usb_set_intfdata(intf, acm);
1224
1225         i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
1226         if (i < 0)
1227                 goto alloc_fail7;
1228
1229         if (cfd) { /* export the country data */
1230                 acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
1231                 if (!acm->country_codes)
1232                         goto skip_countries;
1233                 acm->country_code_size = cfd->bLength - 4;
1234                 memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0,
1235                                                         cfd->bLength - 4);
1236                 acm->country_rel_date = cfd->iCountryCodeRelDate;
1237
1238                 i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
1239                 if (i < 0) {
1240                         kfree(acm->country_codes);
1241                         acm->country_codes = NULL;
1242                         acm->country_code_size = 0;
1243                         goto skip_countries;
1244                 }
1245
1246                 i = device_create_file(&intf->dev,
1247                                                 &dev_attr_iCountryCodeRelDate);
1248                 if (i < 0) {
1249                         device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
1250                         kfree(acm->country_codes);
1251                         acm->country_codes = NULL;
1252                         acm->country_code_size = 0;
1253                         goto skip_countries;
1254                 }
1255         }
1256
1257 skip_countries:
1258         usb_fill_int_urb(acm->ctrlurb, usb_dev,
1259                          usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
1260                          acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
1261                          /* works around buggy devices */
1262                          epctrl->bInterval ? epctrl->bInterval : 0xff);
1263         acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1264         acm->ctrlurb->transfer_dma = acm->ctrl_dma;
1265
1266         dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
1267
1268         acm_set_control(acm, acm->ctrlout);
1269
1270         acm->line.dwDTERate = cpu_to_le32(9600);
1271         acm->line.bDataBits = 8;
1272         acm_set_line(acm, &acm->line);
1273
1274         usb_driver_claim_interface(&acm_driver, data_interface, acm);
1275         usb_set_intfdata(data_interface, acm);
1276
1277         usb_get_intf(control_interface);
1278         tty_register_device(acm_tty_driver, minor, &control_interface->dev);
1279
1280         acm_table[minor] = acm;
1281
1282         return 0;
1283 alloc_fail7:
1284         for (i = 0; i < ACM_NW; i++)
1285                 usb_free_urb(acm->wb[i].urb);
1286 alloc_fail6:
1287         for (i = 0; i < num_rx_buf; i++)
1288                 usb_free_urb(acm->read_urbs[i]);
1289         acm_read_buffers_free(acm);
1290         usb_free_urb(acm->ctrlurb);
1291 alloc_fail5:
1292         acm_write_buffers_free(acm);
1293 alloc_fail4:
1294         usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1295 alloc_fail2:
1296         kfree(acm);
1297 alloc_fail:
1298         return -ENOMEM;
1299 }
1300
1301 static void stop_data_traffic(struct acm *acm)
1302 {
1303         int i;
1304
1305         dev_dbg(&acm->control->dev, "%s\n", __func__);
1306
1307         usb_kill_urb(acm->ctrlurb);
1308         for (i = 0; i < ACM_NW; i++)
1309                 usb_kill_urb(acm->wb[i].urb);
1310         for (i = 0; i < acm->rx_buflimit; i++)
1311                 usb_kill_urb(acm->read_urbs[i]);
1312
1313         cancel_work_sync(&acm->work);
1314 }
1315
1316 static void acm_disconnect(struct usb_interface *intf)
1317 {
1318         struct acm *acm = usb_get_intfdata(intf);
1319         struct usb_device *usb_dev = interface_to_usbdev(intf);
1320         struct tty_struct *tty;
1321
1322         /* sibling interface is already cleaning up */
1323         if (!acm)
1324                 return;
1325
1326         mutex_lock(&open_mutex);
1327         if (acm->country_codes) {
1328                 device_remove_file(&acm->control->dev,
1329                                 &dev_attr_wCountryCodes);
1330                 device_remove_file(&acm->control->dev,
1331                                 &dev_attr_iCountryCodeRelDate);
1332         }
1333         device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1334         acm->dev = NULL;
1335         usb_set_intfdata(acm->control, NULL);
1336         usb_set_intfdata(acm->data, NULL);
1337
1338         stop_data_traffic(acm);
1339
1340         acm_write_buffers_free(acm);
1341         usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer,
1342                           acm->ctrl_dma);
1343         acm_read_buffers_free(acm);
1344
1345         if (!acm->combined_interfaces)
1346                 usb_driver_release_interface(&acm_driver, intf == acm->control ?
1347                                         acm->data : acm->control);
1348
1349         if (acm->port.count == 0) {
1350                 acm_tty_unregister(acm);
1351                 mutex_unlock(&open_mutex);
1352                 return;
1353         }
1354
1355         mutex_unlock(&open_mutex);
1356         tty = tty_port_tty_get(&acm->port);
1357         if (tty) {
1358                 tty_hangup(tty);
1359                 tty_kref_put(tty);
1360         }
1361 }
1362
1363 #ifdef CONFIG_PM
1364 static int acm_suspend(struct usb_interface *intf, pm_message_t message)
1365 {
1366         struct acm *acm = usb_get_intfdata(intf);
1367         int cnt;
1368
1369         spin_lock_irq(&acm->read_lock);
1370         spin_lock(&acm->write_lock);
1371         if (PMSG_IS_AUTO(message)) {
1372                 if (acm->transmitting) {
1373                         spin_unlock(&acm->write_lock);
1374                         spin_unlock_irq(&acm->read_lock);
1375                         return -EBUSY;
1376                 }
1377         }
1378         cnt = acm->susp_count++;
1379         spin_unlock(&acm->write_lock);
1380         spin_unlock_irq(&acm->read_lock);
1381
1382         if (cnt)
1383                 return 0;
1384         /*
1385         we treat opened interfaces differently,
1386         we must guard against open
1387         */
1388         mutex_lock(&acm->mutex);
1389
1390         if (acm->port.count)
1391                 stop_data_traffic(acm);
1392
1393         mutex_unlock(&acm->mutex);
1394         return 0;
1395 }
1396
1397 static int acm_resume(struct usb_interface *intf)
1398 {
1399         struct acm *acm = usb_get_intfdata(intf);
1400         struct urb *urb;
1401         int rv = 0;
1402
1403         mutex_lock(&acm->mutex);
1404         spin_lock_irq(&acm->read_lock);
1405         spin_lock(&acm->write_lock);
1406
1407         if (--acm->susp_count)
1408                 goto out;
1409
1410         if (acm->port.count) {
1411                 rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
1412
1413                 for (;;) {
1414                         urb = usb_get_from_anchor(&acm->delayed);
1415                         if (!urb)
1416                                 break;
1417
1418                         acm_start_wb(acm, urb->context);
1419                 }
1420
1421                 /*
1422                  * delayed error checking because we must
1423                  * do the write path at all cost
1424                  */
1425                 if (rv < 0)
1426                         goto out;
1427
1428                 rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
1429         }
1430 out:
1431         spin_unlock(&acm->write_lock);
1432         spin_unlock_irq(&acm->read_lock);
1433         mutex_unlock(&acm->mutex);
1434
1435         return rv;
1436 }
1437
1438 static int acm_reset_resume(struct usb_interface *intf)
1439 {
1440         struct acm *acm = usb_get_intfdata(intf);
1441         struct tty_struct *tty;
1442
1443         mutex_lock(&acm->mutex);
1444         if (acm->port.count) {
1445                 tty = tty_port_tty_get(&acm->port);
1446                 if (tty) {
1447                         tty_hangup(tty);
1448                         tty_kref_put(tty);
1449                 }
1450         }
1451         mutex_unlock(&acm->mutex);
1452         return acm_resume(intf);
1453 }
1454
1455 #endif /* CONFIG_PM */
1456
1457 #define NOKIA_PCSUITE_ACM_INFO(x) \
1458                 USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
1459                 USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1460                 USB_CDC_ACM_PROTO_VENDOR)
1461
1462 #define SAMSUNG_PCSUITE_ACM_INFO(x) \
1463                 USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
1464                 USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1465                 USB_CDC_ACM_PROTO_VENDOR)
1466
1467 /*
1468  * USB driver structure.
1469  */
1470
1471 static const struct usb_device_id acm_ids[] = {
1472         /* quirky and broken devices */
1473         { USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
1474         .driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1475         { USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
1476         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1477         },
1478         { USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
1479         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1480         },
1481         { USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
1482         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1483         },
1484         { USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
1485         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1486         },
1487         { USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
1488         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1489         },
1490         { USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
1491         .driver_info = SINGLE_RX_URB,
1492         },
1493         { USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
1494         .driver_info = SINGLE_RX_URB, /* firmware bug */
1495         },
1496         { USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
1497         .driver_info = SINGLE_RX_URB, /* firmware bug */
1498         },
1499         { USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
1500         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1501         },
1502         { USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
1503         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1504         },
1505         { USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
1506         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1507         },
1508         { USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
1509         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1510         },
1511         { USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
1512         .driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1513         },
1514         { USB_DEVICE(0x2184, 0x001c) }, /* GW Instek AFG-2225 */
1515         { USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
1516         },
1517         /* Motorola H24 HSPA module: */
1518         { USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
1519         { USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
1520         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1521         },
1522         { USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
1523         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1524         },
1525         { USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
1526         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1527         },
1528         { USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
1529         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1530         },
1531         { USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
1532         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1533         },
1534         { USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
1535         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1536         },
1537         { USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
1538         .driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1539         },
1540
1541         { USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
1542         .driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
1543                                            data interface instead of
1544                                            communications interface.
1545                                            Maybe we should define a new
1546                                            quirk for this. */
1547         },
1548         { USB_DEVICE(0x0572, 0x1340), /* Conexant CX93010-2x UCMxx */
1549         .driver_info = NO_UNION_NORMAL,
1550         },
1551         { USB_DEVICE(0x05f9, 0x4002), /* PSC Scanning, Magellan 800i */
1552         .driver_info = NO_UNION_NORMAL,
1553         },
1554         { USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
1555         .driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1556         },
1557         { USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
1558         .driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1559         },
1560
1561         /* Nokia S60 phones expose two ACM channels. The first is
1562          * a modem and is picked up by the standard AT-command
1563          * information below. The second is 'vendor-specific' but
1564          * is treated as a serial device at the S60 end, so we want
1565          * to expose it on Linux too. */
1566         { NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
1567         { NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
1568         { NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
1569         { NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
1570         { NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
1571         { NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
1572         { NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
1573         { NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
1574         { NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
1575         { NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
1576         { NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
1577         { NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
1578         { NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
1579         { NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
1580         { NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
1581         { NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
1582         { NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
1583         { NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
1584         { NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
1585         { NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
1586         { NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
1587         { NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
1588         { NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
1589         { NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
1590         { NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
1591         { NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
1592         { NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
1593         { NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
1594         { NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
1595         { NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
1596         { NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
1597         { NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
1598         { NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1599         { NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
1600         { NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
1601         { NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
1602         { NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
1603         { NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
1604         { NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
1605         { NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
1606         { NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1607         { NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
1608         { NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
1609         { NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
1610         { NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
1611         { NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
1612         { NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
1613         { NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
1614         { NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
1615         { NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
1616         { NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
1617         { NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
1618         { NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
1619         { NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
1620         { NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
1621         { NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
1622         { NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
1623         { SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */
1624
1625         /* Support for Owen devices */
1626         { USB_DEVICE(0x03eb, 0x0030), }, /* Owen SI30 */
1627
1628         /* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
1629
1630         /* Support Lego NXT using pbLua firmware */
1631         { USB_DEVICE(0x0694, 0xff00),
1632         .driver_info = NOT_A_MODEM,
1633         },
1634
1635         /* Support for Droids MuIn LCD */
1636         { USB_DEVICE(0x04d8, 0x000b),
1637         .driver_info = NO_DATA_INTERFACE,
1638         },
1639
1640         /* control interfaces without any protocol set */
1641         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1642                 USB_CDC_PROTO_NONE) },
1643
1644         /* control interfaces with various AT-command sets */
1645         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1646                 USB_CDC_ACM_PROTO_AT_V25TER) },
1647         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1648                 USB_CDC_ACM_PROTO_AT_PCCA101) },
1649         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1650                 USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
1651         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1652                 USB_CDC_ACM_PROTO_AT_GSM) },
1653         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1654                 USB_CDC_ACM_PROTO_AT_3G) },
1655         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1656                 USB_CDC_ACM_PROTO_AT_CDMA) },
1657
1658         { }
1659 };
1660
1661 MODULE_DEVICE_TABLE(usb, acm_ids);
1662
1663 static struct usb_driver acm_driver = {
1664         .name =         "cdc_acm",
1665         .probe =        acm_probe,
1666         .disconnect =   acm_disconnect,
1667 #ifdef CONFIG_PM
1668         .suspend =      acm_suspend,
1669         .resume =       acm_resume,
1670         .reset_resume = acm_reset_resume,
1671 #endif
1672         .id_table =     acm_ids,
1673 #ifdef CONFIG_PM
1674         .supports_autosuspend = 1,
1675 #endif
1676 };
1677
1678 /*
1679  * TTY driver structures.
1680  */
1681
1682 static const struct tty_operations acm_ops = {
1683         .open =                 acm_tty_open,
1684         .close =                acm_tty_close,
1685         .hangup =               acm_tty_hangup,
1686         .write =                acm_tty_write,
1687         .write_room =           acm_tty_write_room,
1688         .ioctl =                acm_tty_ioctl,
1689         .throttle =             acm_tty_throttle,
1690         .unthrottle =           acm_tty_unthrottle,
1691         .chars_in_buffer =      acm_tty_chars_in_buffer,
1692         .break_ctl =            acm_tty_break_ctl,
1693         .set_termios =          acm_tty_set_termios,
1694         .tiocmget =             acm_tty_tiocmget,
1695         .tiocmset =             acm_tty_tiocmset,
1696 };
1697
1698 /*
1699  * Init / exit.
1700  */
1701
1702 static int __init acm_init(void)
1703 {
1704         int retval;
1705         acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
1706         if (!acm_tty_driver)
1707                 return -ENOMEM;
1708         acm_tty_driver->owner = THIS_MODULE,
1709         acm_tty_driver->driver_name = "acm",
1710         acm_tty_driver->name = "ttyACM",
1711         acm_tty_driver->major = ACM_TTY_MAJOR,
1712         acm_tty_driver->minor_start = 0,
1713         acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
1714         acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
1715         acm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1716         acm_tty_driver->init_termios = tty_std_termios;
1717         acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
1718                                                                 HUPCL | CLOCAL;
1719         tty_set_operations(acm_tty_driver, &acm_ops);
1720
1721         retval = tty_register_driver(acm_tty_driver);
1722         if (retval) {
1723                 put_tty_driver(acm_tty_driver);
1724                 return retval;
1725         }
1726
1727         retval = usb_register(&acm_driver);
1728         if (retval) {
1729                 tty_unregister_driver(acm_tty_driver);
1730                 put_tty_driver(acm_tty_driver);
1731                 return retval;
1732         }
1733
1734         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
1735
1736         return 0;
1737 }
1738
1739 static void __exit acm_exit(void)
1740 {
1741         usb_deregister(&acm_driver);
1742         tty_unregister_driver(acm_tty_driver);
1743         put_tty_driver(acm_tty_driver);
1744 }
1745
1746 module_init(acm_init);
1747 module_exit(acm_exit);
1748
1749 MODULE_AUTHOR(DRIVER_AUTHOR);
1750 MODULE_DESCRIPTION(DRIVER_DESC);
1751 MODULE_LICENSE("GPL");
1752 MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);