drivers/net/wireless/rt2x00/rt2x00usb.c

   1 /*
   2         Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
   3         <http://rt2x00.serialmonkey.com>
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the
  17         Free Software Foundation, Inc.,
  18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22         Module: rt2x00usb
  23         Abstract: rt2x00 generic usb device routines.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/usb.h>
  29 #include <linux/bug.h>
  30
  31 #include "rt2x00.h"
  32 #include "rt2x00usb.h"
  33
  34 /*
  35  * Interfacing with the HW.
  36  */
  37 int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
  38                              const u8 request, const u8 requesttype,
  39                              const u16 offset, const u16 value,
  40                              void *buffer, const u16 buffer_length,
  41                              const int timeout)
  42 {
  43         struct usb_device *usb_dev =
  44                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
  45         int status;
  46         unsigned int i;
  47         unsigned int pipe =
  48             (requesttype == USB_VENDOR_REQUEST_IN) ?
  49             usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
  50
  51
  52         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
  53                 status = usb_control_msg(usb_dev, pipe, request, requesttype,
  54                                          value, offset, buffer, buffer_length,
  55                                          timeout);
  56                 if (status >= 0)
  57                         return 0;
  58
  59                 /*
  60                  * Check for errors
  61                  * -ENODEV: Device has disappeared, no point continuing.
  62                  * All other errors: Try again.
  63                  */
  64                 else if (status == -ENODEV)
  65                         break;
  66         }
  67
  68         ERROR(rt2x00dev,
  69               "Vendor Request 0x%02x failed for offset 0x%04x with error %d.\n",
  70               request, offset, status);
  71
  72         return status;
  73 }
  74 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
  75
  76 int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
  77                                    const u8 request, const u8 requesttype,
  78                                    const u16 offset, void *buffer,
  79                                    const u16 buffer_length, const int timeout)
  80 {
  81         int status;
  82
  83         BUG_ON(!mutex_is_locked(&rt2x00dev->usb_cache_mutex));
  84
  85         /*
  86          * Check for Cache availability.
  87          */
  88         if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
  89                 ERROR(rt2x00dev, "CSR cache not available.\n");
  90                 return -ENOMEM;
  91         }
  92
  93         if (requesttype == USB_VENDOR_REQUEST_OUT)
  94                 memcpy(rt2x00dev->csr.cache, buffer, buffer_length);
  95
  96         status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
  97                                           offset, 0, rt2x00dev->csr.cache,
  98                                           buffer_length, timeout);
  99
 100         if (!status && requesttype == USB_VENDOR_REQUEST_IN)
 101                 memcpy(buffer, rt2x00dev->csr.cache, buffer_length);
 102
 103         return status;
 104 }
 105 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
 106
 107 int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
 108                                   const u8 request, const u8 requesttype,
 109                                   const u16 offset, void *buffer,
 110                                   const u16 buffer_length, const int timeout)
 111 {
 112         int status;
 113
 114         mutex_lock(&rt2x00dev->usb_cache_mutex);
 115
 116         status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
 117                                                 requesttype, offset, buffer,
 118                                                 buffer_length, timeout);
 119
 120         mutex_unlock(&rt2x00dev->usb_cache_mutex);
 121
 122         return status;
 123 }
 124 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
 125
 126 /*
 127  * TX data handlers.
 128  */
 129 static void rt2x00usb_interrupt_txdone(struct urb *urb)
 130 {
 131         struct queue_entry *entry = (struct queue_entry *)urb->context;
 132         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 133         struct txdone_entry_desc txdesc;
 134         enum data_queue_qid qid = skb_get_queue_mapping(entry->skb);
 135
 136         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 137             !__test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 138                 return;
 139
 140         /*
 141          * Remove the descriptor data from the buffer.
 142          */
 143         skb_pull(entry->skb, entry->queue->desc_size);
 144
 145         /*
 146          * Obtain the status about this packet.
 147          * Note that when the status is 0 it does not mean the
 148          * frame was send out correctly. It only means the frame
 149          * was succesfully pushed to the hardware, we have no
 150          * way to determine the transmission status right now.
 151          * (Only indirectly by looking at the failed TX counters
 152          * in the register).
 153          */
 154         if (!urb->status)
 155                 __set_bit(TXDONE_UNKNOWN, &txdesc.flags);
 156         else
 157                 __set_bit(TXDONE_FAILURE, &txdesc.flags);
 158         txdesc.retry = 0;
 159
 160         rt2x00lib_txdone(entry, &txdesc);
 161
 162         /*
 163          * Make this entry available for reuse.
 164          */
 165         entry->flags = 0;
 166         rt2x00queue_index_inc(entry->queue, Q_INDEX_DONE);
 167
 168         /*
 169          * If the data queue was below the threshold before the txdone
 170          * handler we must make sure the packet queue in the mac80211 stack
 171          * is reenabled when the txdone handler has finished.
 172          */
 173         if (!rt2x00queue_threshold(entry->queue))
 174                 ieee80211_wake_queue(rt2x00dev->hw, qid);
 175 }
 176
 177 int rt2x00usb_write_tx_data(struct queue_entry *entry)
 178 {
 179         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 180         struct usb_device *usb_dev =
 181                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
 182         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 183         struct skb_frame_desc *skbdesc;
 184         u32 length;
 185
 186         /*
 187          * Add the descriptor in front of the skb.
 188          */
 189         skb_push(entry->skb, entry->queue->desc_size);
 190         memset(entry->skb->data, 0, entry->queue->desc_size);
 191
 192         /*
 193          * Fill in skb descriptor
 194          */
 195         skbdesc = get_skb_frame_desc(entry->skb);
 196         memset(skbdesc, 0, sizeof(*skbdesc));
 197         skbdesc->desc = entry->skb->data;
 198         skbdesc->desc_len = entry->queue->desc_size;
 199         skbdesc->entry = entry;
 200
 201         /*
 202          * USB devices cannot blindly pass the skb->len as the
 203          * length of the data to usb_fill_bulk_urb. Pass the skb
 204          * to the driver to determine what the length should be.
 205          */
 206         length = rt2x00dev->ops->lib->get_tx_data_len(rt2x00dev, entry->skb);
 207
 208         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
 209                           usb_sndbulkpipe(usb_dev, 1),
 210                           entry->skb->data, length,
 211                           rt2x00usb_interrupt_txdone, entry);
 212
 213         return 0;
 214 }
 215 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
 216
 217 static inline void rt2x00usb_kick_tx_entry(struct queue_entry *entry)
 218 {
 219         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 220
 221         if (__test_and_clear_bit(ENTRY_DATA_PENDING, &entry->flags))
 222                 usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
 223 }
 224
 225 void rt2x00usb_kick_tx_queue(struct rt2x00_dev *rt2x00dev,
 226                              const enum data_queue_qid qid)
 227 {
 228         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, qid);
 229         unsigned long irqflags;
 230         unsigned int index;
 231         unsigned int index_done;
 232         unsigned int i;
 233
 234         /*
 235          * Only protect the range we are going to loop over,
 236          * if during our loop a extra entry is set to pending
 237          * it should not be kicked during this run, since it
 238          * is part of another TX operation.
 239          */
 240         spin_lock_irqsave(&queue->lock, irqflags);
 241         index = queue->index[Q_INDEX];
 242         index_done = queue->index[Q_INDEX_DONE];
 243         spin_unlock_irqrestore(&queue->lock, irqflags);
 244
 245         /*
 246          * Start from the TX done pointer, this guarentees that we will
 247          * send out all frames in the correct order.
 248          */
 249         if (index_done < index) {
 250                 for (i = index_done; i < index; i++)
 251                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
 252         } else {
 253                 for (i = index_done; i < queue->limit; i++)
 254                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
 255
 256                 for (i = 0; i < index; i++)
 257                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
 258         }
 259 }
 260 EXPORT_SYMBOL_GPL(rt2x00usb_kick_tx_queue);
 261
 262 /*
 263  * RX data handlers.
 264  */
 265 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
 266 {
 267         struct queue_entry *entry = (struct queue_entry *)urb->context;
 268         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 269         struct sk_buff *skb;
 270         struct skb_frame_desc *skbdesc;
 271         struct rxdone_entry_desc rxdesc;
 272         u8 rxd[32];
 273
 274         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 275             !test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 276                 return;
 277
 278         /*
 279          * Check if the received data is simply too small
 280          * to be actually valid, or if the urb is signaling
 281          * a problem.
 282          */
 283         if (urb->actual_length < entry->queue->desc_size || urb->status)
 284                 goto skip_entry;
 285
 286         /*
 287          * Fill in skb descriptor
 288          */
 289         skbdesc = get_skb_frame_desc(entry->skb);
 290         memset(skbdesc, 0, sizeof(*skbdesc));
 291         skbdesc->entry = entry;
 292         skbdesc->desc = rxd;
 293         skbdesc->desc_len = entry->queue->desc_size;
 294
 295         memset(&rxdesc, 0, sizeof(rxdesc));
 296         rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);
 297
 298         /*
 299          * Allocate a new sk buffer to replace the current one.
 300          * If allocation fails, we should drop the current frame
 301          * so we can recycle the existing sk buffer for the new frame.
 302          */
 303         skb = rt2x00queue_alloc_rxskb(entry->queue);
 304         if (!skb)
 305                 goto skip_entry;
 306
 307         /*
 308          * Send the frame to rt2x00lib for further processing.
 309          */
 310         rt2x00lib_rxdone(entry, &rxdesc);
 311
 312         /*
 313          * Replace current entry's skb with the newly allocated one,
 314          * and reinitialize the urb.
 315          */
 316         entry->skb = skb;
 317         urb->transfer_buffer = entry->skb->data;
 318         urb->transfer_buffer_length = entry->skb->len;
 319
 320 skip_entry:
 321         if (test_bit(DEVICE_ENABLED_RADIO, &entry->queue->rt2x00dev->flags)) {
 322                 __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 323                 usb_submit_urb(urb, GFP_ATOMIC);
 324         }
 325
 326         rt2x00queue_index_inc(entry->queue, Q_INDEX);
 327 }
 328
 329 /*
 330  * Radio handlers
 331  */
 332 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 333 {
 334         struct queue_entry_priv_usb *entry_priv;
 335         struct queue_entry_priv_usb_bcn *bcn_priv;
 336         unsigned int i;
 337
 338         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0, 0,
 339                                     REGISTER_TIMEOUT);
 340
 341         /*
 342          * Cancel all queues.
 343          */
 344         for (i = 0; i < rt2x00dev->rx->limit; i++) {
 345                 entry_priv = rt2x00dev->rx->entries[i].priv_data;
 346                 usb_kill_urb(entry_priv->urb);
 347         }
 348
 349         /*
 350          * Kill guardian urb (if required by driver).
 351          */
 352         if (!test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
 353                 return;
 354
 355         for (i = 0; i < rt2x00dev->bcn->limit; i++) {
 356                 bcn_priv = rt2x00dev->bcn->entries[i].priv_data;
 357                 if (bcn_priv->guardian_urb)
 358                         usb_kill_urb(bcn_priv->guardian_urb);
 359         }
 360 }
 361 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
 362
 363 /*
 364  * Device initialization handlers.
 365  */
 366 void rt2x00usb_init_rxentry(struct rt2x00_dev *rt2x00dev,
 367                             struct queue_entry *entry)
 368 {
 369         struct usb_device *usb_dev =
 370                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
 371         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 372
 373         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
 374                           usb_rcvbulkpipe(usb_dev, 1),
 375                           entry->skb->data, entry->skb->len,
 376                           rt2x00usb_interrupt_rxdone, entry);
 377
 378         __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 379         usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
 380 }
 381 EXPORT_SYMBOL_GPL(rt2x00usb_init_rxentry);
 382
 383 void rt2x00usb_init_txentry(struct rt2x00_dev *rt2x00dev,
 384                             struct queue_entry *entry)
 385 {
 386         entry->flags = 0;
 387 }
 388 EXPORT_SYMBOL_GPL(rt2x00usb_init_txentry);
 389
 390 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
 391                                struct data_queue *queue)
 392 {
 393         struct queue_entry_priv_usb *entry_priv;
 394         struct queue_entry_priv_usb_bcn *bcn_priv;
 395         unsigned int i;
 396
 397         for (i = 0; i < queue->limit; i++) {
 398                 entry_priv = queue->entries[i].priv_data;
 399                 entry_priv->urb = usb_alloc_urb(0, GFP_KERNEL);
 400                 if (!entry_priv->urb)
 401                         return -ENOMEM;
 402         }
 403
 404         /*
 405          * If this is not the beacon queue or
 406          * no guardian byte was required for the beacon,
 407          * then we are done.
 408          */
 409         if (rt2x00dev->bcn != queue ||
 410             !test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
 411                 return 0;
 412
 413         for (i = 0; i < queue->limit; i++) {
 414                 bcn_priv = queue->entries[i].priv_data;
 415                 bcn_priv->guardian_urb = usb_alloc_urb(0, GFP_KERNEL);
 416                 if (!bcn_priv->guardian_urb)
 417                         return -ENOMEM;
 418         }
 419
 420         return 0;
 421 }
 422
 423 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
 424                                struct data_queue *queue)
 425 {
 426         struct queue_entry_priv_usb *entry_priv;
 427         struct queue_entry_priv_usb_bcn *bcn_priv;
 428         unsigned int i;
 429
 430         if (!queue->entries)
 431                 return;
 432
 433         for (i = 0; i < queue->limit; i++) {
 434                 entry_priv = queue->entries[i].priv_data;
 435                 usb_kill_urb(entry_priv->urb);
 436                 usb_free_urb(entry_priv->urb);
 437                 if (queue->entries[i].skb)
 438                         kfree_skb(queue->entries[i].skb);
 439         }
 440
 441         /*
 442          * If this is not the beacon queue or
 443          * no guardian byte was required for the beacon,
 444          * then we are done.
 445          */
 446         if (rt2x00dev->bcn != queue ||
 447             !test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
 448                 return;
 449
 450         for (i = 0; i < queue->limit; i++) {
 451                 bcn_priv = queue->entries[i].priv_data;
 452                 usb_kill_urb(bcn_priv->guardian_urb);
 453                 usb_free_urb(bcn_priv->guardian_urb);
 454         }
 455 }
 456
 457 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
 458 {
 459         struct data_queue *queue;
 460         struct sk_buff *skb;
 461         unsigned int entry_size;
 462         unsigned int i;
 463         int uninitialized_var(status);
 464
 465         /*
 466          * Allocate DMA
 467          */
 468         queue_for_each(rt2x00dev, queue) {
 469                 status = rt2x00usb_alloc_urb(rt2x00dev, queue);
 470                 if (status)
 471                         goto exit;
 472         }
 473
 474         /*
 475          * For the RX queue, skb's should be allocated.
 476          */
 477         entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
 478         for (i = 0; i < rt2x00dev->rx->limit; i++) {
 479                 skb = rt2x00queue_alloc_rxskb(rt2x00dev->rx);
 480                 if (!skb)
 481                         goto exit;
 482
 483                 rt2x00dev->rx->entries[i].skb = skb;
 484         }
 485
 486         return 0;
 487
 488 exit:
 489         rt2x00usb_uninitialize(rt2x00dev);
 490
 491         return status;
 492 }
 493 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
 494
 495 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
 496 {
 497         struct data_queue *queue;
 498
 499         queue_for_each(rt2x00dev, queue)
 500                 rt2x00usb_free_urb(rt2x00dev, queue);
 501 }
 502 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
 503
 504 /*
 505  * USB driver handlers.
 506  */
 507 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
 508 {
 509         kfree(rt2x00dev->rf);
 510         rt2x00dev->rf = NULL;
 511
 512         kfree(rt2x00dev->eeprom);
 513         rt2x00dev->eeprom = NULL;
 514
 515         kfree(rt2x00dev->csr.cache);
 516         rt2x00dev->csr.cache = NULL;
 517 }
 518
 519 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
 520 {
 521         rt2x00dev->csr.cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
 522         if (!rt2x00dev->csr.cache)
 523                 goto exit;
 524
 525         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
 526         if (!rt2x00dev->eeprom)
 527                 goto exit;
 528
 529         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
 530         if (!rt2x00dev->rf)
 531                 goto exit;
 532
 533         return 0;
 534
 535 exit:
 536         ERROR_PROBE("Failed to allocate registers.\n");
 537
 538         rt2x00usb_free_reg(rt2x00dev);
 539
 540         return -ENOMEM;
 541 }
 542
 543 int rt2x00usb_probe(struct usb_interface *usb_intf,
 544                     const struct usb_device_id *id)
 545 {
 546         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
 547         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
 548         struct ieee80211_hw *hw;
 549         struct rt2x00_dev *rt2x00dev;
 550         int retval;
 551
 552         usb_dev = usb_get_dev(usb_dev);
 553
 554         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
 555         if (!hw) {
 556                 ERROR_PROBE("Failed to allocate hardware.\n");
 557                 retval = -ENOMEM;
 558                 goto exit_put_device;
 559         }
 560
 561         usb_set_intfdata(usb_intf, hw);
 562
 563         rt2x00dev = hw->priv;
 564         rt2x00dev->dev = &usb_intf->dev;
 565         rt2x00dev->ops = ops;
 566         rt2x00dev->hw = hw;
 567         mutex_init(&rt2x00dev->usb_cache_mutex);
 568
 569         rt2x00dev->usb_maxpacket =
 570             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
 571         if (!rt2x00dev->usb_maxpacket)
 572                 rt2x00dev->usb_maxpacket = 1;
 573
 574         retval = rt2x00usb_alloc_reg(rt2x00dev);
 575         if (retval)
 576                 goto exit_free_device;
 577
 578         retval = rt2x00lib_probe_dev(rt2x00dev);
 579         if (retval)
 580                 goto exit_free_reg;
 581
 582         return 0;
 583
 584 exit_free_reg:
 585         rt2x00usb_free_reg(rt2x00dev);
 586
 587 exit_free_device:
 588         ieee80211_free_hw(hw);
 589
 590 exit_put_device:
 591         usb_put_dev(usb_dev);
 592
 593         usb_set_intfdata(usb_intf, NULL);
 594
 595         return retval;
 596 }
 597 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
 598
 599 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
 600 {
 601         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 602         struct rt2x00_dev *rt2x00dev = hw->priv;
 603
 604         /*
 605          * Free all allocated data.
 606          */
 607         rt2x00lib_remove_dev(rt2x00dev);
 608         rt2x00usb_free_reg(rt2x00dev);
 609         ieee80211_free_hw(hw);
 610
 611         /*
 612          * Free the USB device data.
 613          */
 614         usb_set_intfdata(usb_intf, NULL);
 615         usb_put_dev(interface_to_usbdev(usb_intf));
 616 }
 617 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
 618
 619 #ifdef CONFIG_PM
 620 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
 621 {
 622         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 623         struct rt2x00_dev *rt2x00dev = hw->priv;
 624         int retval;
 625
 626         retval = rt2x00lib_suspend(rt2x00dev, state);
 627         if (retval)
 628                 return retval;
 629
 630         rt2x00usb_free_reg(rt2x00dev);
 631
 632         /*
 633          * Decrease usbdev refcount.
 634          */
 635         usb_put_dev(interface_to_usbdev(usb_intf));
 636
 637         return 0;
 638 }
 639 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
 640
 641 int rt2x00usb_resume(struct usb_interface *usb_intf)
 642 {
 643         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 644         struct rt2x00_dev *rt2x00dev = hw->priv;
 645         int retval;
 646
 647         usb_get_dev(interface_to_usbdev(usb_intf));
 648
 649         retval = rt2x00usb_alloc_reg(rt2x00dev);
 650         if (retval)
 651                 return retval;
 652
 653         retval = rt2x00lib_resume(rt2x00dev);
 654         if (retval)
 655                 goto exit_free_reg;
 656
 657         return 0;
 658
 659 exit_free_reg:
 660         rt2x00usb_free_reg(rt2x00dev);
 661
 662         return retval;
 663 }
 664 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
 665 #endif /* CONFIG_PM */
 666
 667 /*
 668  * rt2x00usb module information.
 669  */
 670 MODULE_AUTHOR(DRV_PROJECT);
 671 MODULE_VERSION(DRV_VERSION);
 672 MODULE_DESCRIPTION("rt2x00 usb library");
 673 MODULE_LICENSE("GPL");