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 = rt2x00dev_usb_dev(rt2x00dev);
  44         int status;
  45         unsigned int i;
  46         unsigned int pipe =
  47             (requesttype == USB_VENDOR_REQUEST_IN) ?
  48             usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
  49
  50
  51         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
  52                 status = usb_control_msg(usb_dev, pipe, request, requesttype,
  53                                          value, offset, buffer, buffer_length,
  54                                          timeout);
  55                 if (status >= 0)
  56                         return 0;
  57
  58                 /*
  59                  * Check for errors
  60                  * -ENODEV: Device has disappeared, no point continuing.
  61                  * All other errors: Try again.
  62                  */
  63                 else if (status == -ENODEV)
  64                         break;
  65         }
  66
  67         ERROR(rt2x00dev,
  68               "Vendor Request 0x%02x failed for offset 0x%04x with error %d.\n",
  69               request, offset, status);
  70
  71         return status;
  72 }
  73 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
  74
  75 int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
  76                                    const u8 request, const u8 requesttype,
  77                                    const u16 offset, void *buffer,
  78                                    const u16 buffer_length, const int timeout)
  79 {
  80         int status;
  81
  82         BUG_ON(!mutex_is_locked(&rt2x00dev->usb_cache_mutex));
  83
  84         /*
  85          * Check for Cache availability.
  86          */
  87         if (unlikely(!rt2x00dev->csr_cache || buffer_length > CSR_CACHE_SIZE)) {
  88                 ERROR(rt2x00dev, "CSR cache not available.\n");
  89                 return -ENOMEM;
  90         }
  91
  92         if (requesttype == USB_VENDOR_REQUEST_OUT)
  93                 memcpy(rt2x00dev->csr_cache, buffer, buffer_length);
  94
  95         status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
  96                                           offset, 0, rt2x00dev->csr_cache,
  97                                           buffer_length, timeout);
  98
  99         if (!status && requesttype == USB_VENDOR_REQUEST_IN)
 100                 memcpy(buffer, rt2x00dev->csr_cache, buffer_length);
 101
 102         return status;
 103 }
 104 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
 105
 106 int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
 107                                   const u8 request, const u8 requesttype,
 108                                   const u16 offset, void *buffer,
 109                                   const u16 buffer_length, const int timeout)
 110 {
 111         int status;
 112
 113         mutex_lock(&rt2x00dev->usb_cache_mutex);
 114
 115         status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
 116                                                 requesttype, offset, buffer,
 117                                                 buffer_length, timeout);
 118
 119         mutex_unlock(&rt2x00dev->usb_cache_mutex);
 120
 121         return status;
 122 }
 123 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
 124
 125 /*
 126  * TX data handlers.
 127  */
 128 static void rt2x00usb_interrupt_txdone(struct urb *urb)
 129 {
 130         struct queue_entry *entry = (struct queue_entry *)urb->context;
 131         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 132         struct queue_entry_priv_usb_tx *priv_tx = entry->priv_data;
 133         struct txdone_entry_desc txdesc;
 134         __le32 *txd = (__le32 *)entry->skb->data;
 135         u32 word;
 136
 137         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 138             !__test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 139                 return;
 140
 141         rt2x00_desc_read(txd, 0, &word);
 142
 143         /*
 144          * Remove the descriptor data from the buffer.
 145          */
 146         skb_pull(entry->skb, entry->queue->desc_size);
 147
 148         /*
 149          * Obtain the status about this packet.
 150          */
 151         txdesc.status = !urb->status ? TX_SUCCESS : TX_FAIL_RETRY;
 152         txdesc.retry = 0;
 153         txdesc.control = &priv_tx->control;
 154
 155         rt2x00lib_txdone(entry, &txdesc);
 156
 157         /*
 158          * Make this entry available for reuse.
 159          */
 160         entry->flags = 0;
 161         rt2x00queue_index_inc(entry->queue, Q_INDEX_DONE);
 162
 163         /*
 164          * If the data queue was full before the txdone handler
 165          * we must make sure the packet queue in the mac80211 stack
 166          * is reenabled when the txdone handler has finished.
 167          */
 168         if (!rt2x00queue_full(entry->queue))
 169                 ieee80211_wake_queue(rt2x00dev->hw, priv_tx->control.queue);
 170 }
 171
 172 int rt2x00usb_write_tx_data(struct rt2x00_dev *rt2x00dev,
 173                             struct data_queue *queue, struct sk_buff *skb,
 174                             struct ieee80211_tx_control *control)
 175 {
 176         struct usb_device *usb_dev = rt2x00dev_usb_dev(rt2x00dev);
 177         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 178         struct queue_entry_priv_usb_tx *priv_tx = entry->priv_data;
 179         struct skb_frame_desc *skbdesc;
 180         u32 length;
 181
 182         if (rt2x00queue_full(queue))
 183                 return -EINVAL;
 184
 185         if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
 186                 ERROR(rt2x00dev,
 187                       "Arrived at non-free entry in the non-full queue %d.\n"
 188                       "Please file bug report to %s.\n",
 189                       control->queue, DRV_PROJECT);
 190                 return -EINVAL;
 191         }
 192
 193         /*
 194          * Add the descriptor in front of the skb.
 195          */
 196         skb_push(skb, queue->desc_size);
 197         memset(skb->data, 0, queue->desc_size);
 198
 199         /*
 200          * Fill in skb descriptor
 201          */
 202         skbdesc = get_skb_frame_desc(skb);
 203         memset(skbdesc, 0, sizeof(*skbdesc));
 204         skbdesc->data = skb->data + queue->desc_size;
 205         skbdesc->data_len = queue->data_size;
 206         skbdesc->desc = skb->data;
 207         skbdesc->desc_len = queue->desc_size;
 208         skbdesc->entry = entry;
 209
 210         rt2x00lib_write_tx_desc(rt2x00dev, skb, control);
 211
 212         /*
 213          * USB devices cannot blindly pass the skb->len as the
 214          * length of the data to usb_fill_bulk_urb. Pass the skb
 215          * to the driver to determine what the length should be.
 216          */
 217         length = rt2x00dev->ops->lib->get_tx_data_len(rt2x00dev, skb);
 218
 219         /*
 220          * Initialize URB and send the frame to the device.
 221          */
 222         __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 223         usb_fill_bulk_urb(priv_tx->urb, usb_dev, usb_sndbulkpipe(usb_dev, 1),
 224                           skb->data, length, rt2x00usb_interrupt_txdone, entry);
 225         usb_submit_urb(priv_tx->urb, GFP_ATOMIC);
 226
 227         rt2x00queue_index_inc(queue, Q_INDEX);
 228
 229         return 0;
 230 }
 231 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
 232
 233 /*
 234  * RX data handlers.
 235  */
 236 static struct sk_buff* rt2x00usb_alloc_rxskb(struct data_queue *queue)
 237 {
 238         struct sk_buff *skb;
 239         unsigned int frame_size;
 240
 241         /*
 242          * As alignment we use 2 and not NET_IP_ALIGN because we need
 243          * to be sure we have 2 bytes room in the head. (NET_IP_ALIGN
 244          * can be 0 on some hardware). We use these 2 bytes for frame
 245          * alignment later, we assume that the chance that
 246          * header_size % 4 == 2 is bigger then header_size % 2 == 0
 247          * and thus optimize alignment by reserving the 2 bytes in
 248          * advance.
 249          */
 250         frame_size = queue->data_size + queue->desc_size;
 251         skb = dev_alloc_skb(frame_size + 2);
 252         if (!skb)
 253                 return NULL;
 254
 255         skb_reserve(skb, 2);
 256         skb_put(skb, frame_size);
 257
 258         return skb;
 259 }
 260
 261 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
 262 {
 263         struct queue_entry *entry = (struct queue_entry *)urb->context;
 264         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 265         struct sk_buff *skb;
 266         struct skb_frame_desc *skbdesc;
 267         struct rxdone_entry_desc rxdesc;
 268
 269         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 270             !test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 271                 return;
 272
 273         /*
 274          * Check if the received data is simply too small
 275          * to be actually valid, or if the urb is signaling
 276          * a problem.
 277          */
 278         if (urb->actual_length < entry->queue->desc_size || urb->status)
 279                 goto skip_entry;
 280
 281         /*
 282          * Fill in skb descriptor
 283          */
 284         skbdesc = get_skb_frame_desc(entry->skb);
 285         memset(skbdesc, 0, sizeof(*skbdesc));
 286         skbdesc->entry = entry;
 287
 288         memset(&rxdesc, 0, sizeof(rxdesc));
 289         rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);
 290
 291         /*
 292          * Allocate a new sk buffer to replace the current one.
 293          * If allocation fails, we should drop the current frame
 294          * so we can recycle the existing sk buffer for the new frame.
 295          */
 296         skb = rt2x00usb_alloc_rxskb(entry->queue);
 297         if (!skb)
 298                 goto skip_entry;
 299
 300         /*
 301          * Send the frame to rt2x00lib for further processing.
 302          */
 303         rt2x00lib_rxdone(entry, &rxdesc);
 304
 305         /*
 306          * Replace current entry's skb with the newly allocated one,
 307          * and reinitialize the urb.
 308          */
 309         entry->skb = skb;
 310         urb->transfer_buffer = entry->skb->data;
 311         urb->transfer_buffer_length = entry->skb->len;
 312
 313 skip_entry:
 314         if (test_bit(DEVICE_ENABLED_RADIO, &entry->queue->rt2x00dev->flags)) {
 315                 __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 316                 usb_submit_urb(urb, GFP_ATOMIC);
 317         }
 318
 319         rt2x00queue_index_inc(entry->queue, Q_INDEX);
 320 }
 321
 322 /*
 323  * Radio handlers
 324  */
 325 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 326 {
 327         struct queue_entry_priv_usb_rx *priv_rx;
 328         struct queue_entry_priv_usb_tx *priv_tx;
 329         struct data_queue *queue;
 330         unsigned int i;
 331
 332         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0x0000, 0x0000,
 333                                     REGISTER_TIMEOUT);
 334
 335         /*
 336          * Cancel all queues.
 337          */
 338         for (i = 0; i < rt2x00dev->rx->limit; i++) {
 339                 priv_rx = rt2x00dev->rx->entries[i].priv_data;
 340                 usb_kill_urb(priv_rx->urb);
 341         }
 342
 343         txall_queue_for_each(rt2x00dev, queue) {
 344                 for (i = 0; i < queue->limit; i++) {
 345                         priv_tx = queue->entries[i].priv_data;
 346                         usb_kill_urb(priv_tx->urb);
 347                 }
 348         }
 349 }
 350 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
 351
 352 /*
 353  * Device initialization handlers.
 354  */
 355 void rt2x00usb_init_rxentry(struct rt2x00_dev *rt2x00dev,
 356                             struct queue_entry *entry)
 357 {
 358         struct usb_device *usb_dev = rt2x00dev_usb_dev(rt2x00dev);
 359         struct queue_entry_priv_usb_rx *priv_rx = entry->priv_data;
 360
 361         usb_fill_bulk_urb(priv_rx->urb, usb_dev,
 362                           usb_rcvbulkpipe(usb_dev, 1),
 363                           entry->skb->data, entry->skb->len,
 364                           rt2x00usb_interrupt_rxdone, entry);
 365
 366         __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 367         usb_submit_urb(priv_rx->urb, GFP_ATOMIC);
 368 }
 369 EXPORT_SYMBOL_GPL(rt2x00usb_init_rxentry);
 370
 371 void rt2x00usb_init_txentry(struct rt2x00_dev *rt2x00dev,
 372                             struct queue_entry *entry)
 373 {
 374         entry->flags = 0;
 375 }
 376 EXPORT_SYMBOL_GPL(rt2x00usb_init_txentry);
 377
 378 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
 379                                struct data_queue *queue)
 380 {
 381         struct queue_entry_priv_usb_rx *priv_rx;
 382         struct queue_entry_priv_usb_tx *priv_tx;
 383         struct queue_entry_priv_usb_bcn *priv_bcn;
 384         struct urb *urb;
 385         unsigned int guardian =
 386             test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags);
 387         unsigned int i;
 388
 389         /*
 390          * Allocate the URB's
 391          */
 392         for (i = 0; i < queue->limit; i++) {
 393                 urb = usb_alloc_urb(0, GFP_KERNEL);
 394                 if (!urb)
 395                         return -ENOMEM;
 396
 397                 if (queue->qid == QID_RX) {
 398                         priv_rx = queue->entries[i].priv_data;
 399                         priv_rx->urb = urb;
 400                 } else if (queue->qid == QID_MGMT && guardian) {
 401                         priv_bcn = queue->entries[i].priv_data;
 402                         priv_bcn->urb = urb;
 403
 404                         urb = usb_alloc_urb(0, GFP_KERNEL);
 405                         if (!urb)
 406                                 return -ENOMEM;
 407
 408                         priv_bcn->guardian_urb = urb;
 409                 } else {
 410                         priv_tx = queue->entries[i].priv_data;
 411                         priv_tx->urb = urb;
 412                 }
 413         }
 414
 415         return 0;
 416 }
 417
 418 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
 419                                struct data_queue *queue)
 420 {
 421         struct queue_entry_priv_usb_rx *priv_rx;
 422         struct queue_entry_priv_usb_tx *priv_tx;
 423         struct queue_entry_priv_usb_bcn *priv_bcn;
 424         struct urb *urb;
 425         unsigned int guardian =
 426             test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags);
 427         unsigned int i;
 428
 429         if (!queue->entries)
 430                 return;
 431
 432         for (i = 0; i < queue->limit; i++) {
 433                 if (queue->qid == QID_RX) {
 434                         priv_rx = queue->entries[i].priv_data;
 435                         urb = priv_rx->urb;
 436                 } else if (queue->qid == QID_MGMT && guardian) {
 437                         priv_bcn = queue->entries[i].priv_data;
 438
 439                         usb_kill_urb(priv_bcn->guardian_urb);
 440                         usb_free_urb(priv_bcn->guardian_urb);
 441
 442                         urb = priv_bcn->urb;
 443                 } else {
 444                         priv_tx = queue->entries[i].priv_data;
 445                         urb = priv_tx->urb;
 446                 }
 447
 448                 usb_kill_urb(urb);
 449                 usb_free_urb(urb);
 450                 if (queue->entries[i].skb)
 451                         kfree_skb(queue->entries[i].skb);
 452         }
 453 }
 454
 455 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
 456 {
 457         struct data_queue *queue;
 458         struct sk_buff *skb;
 459         unsigned int entry_size;
 460         unsigned int i;
 461         int uninitialized_var(status);
 462
 463         /*
 464          * Allocate DMA
 465          */
 466         queue_for_each(rt2x00dev, queue) {
 467                 status = rt2x00usb_alloc_urb(rt2x00dev, queue);
 468                 if (status)
 469                         goto exit;
 470         }
 471
 472         /*
 473          * For the RX queue, skb's should be allocated.
 474          */
 475         entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
 476         for (i = 0; i < rt2x00dev->rx->limit; i++) {
 477                 skb = rt2x00usb_alloc_rxskb(rt2x00dev->rx);
 478                 if (!skb)
 479                         goto exit;
 480
 481                 rt2x00dev->rx->entries[i].skb = skb;
 482         }
 483
 484         return 0;
 485
 486 exit:
 487         rt2x00usb_uninitialize(rt2x00dev);
 488
 489         return status;
 490 }
 491 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
 492
 493 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
 494 {
 495         struct data_queue *queue;
 496
 497         queue_for_each(rt2x00dev, queue)
 498                 rt2x00usb_free_urb(rt2x00dev, queue);
 499 }
 500 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
 501
 502 /*
 503  * USB driver handlers.
 504  */
 505 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
 506 {
 507         kfree(rt2x00dev->rf);
 508         rt2x00dev->rf = NULL;
 509
 510         kfree(rt2x00dev->eeprom);
 511         rt2x00dev->eeprom = NULL;
 512
 513         kfree(rt2x00dev->csr_cache);
 514         rt2x00dev->csr_cache = NULL;
 515 }
 516
 517 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
 518 {
 519         rt2x00dev->csr_cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
 520         if (!rt2x00dev->csr_cache)
 521                 goto exit;
 522
 523         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
 524         if (!rt2x00dev->eeprom)
 525                 goto exit;
 526
 527         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
 528         if (!rt2x00dev->rf)
 529                 goto exit;
 530
 531         return 0;
 532
 533 exit:
 534         ERROR_PROBE("Failed to allocate registers.\n");
 535
 536         rt2x00usb_free_reg(rt2x00dev);
 537
 538         return -ENOMEM;
 539 }
 540
 541 int rt2x00usb_probe(struct usb_interface *usb_intf,
 542                     const struct usb_device_id *id)
 543 {
 544         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
 545         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
 546         struct ieee80211_hw *hw;
 547         struct rt2x00_dev *rt2x00dev;
 548         int retval;
 549
 550         usb_dev = usb_get_dev(usb_dev);
 551
 552         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
 553         if (!hw) {
 554                 ERROR_PROBE("Failed to allocate hardware.\n");
 555                 retval = -ENOMEM;
 556                 goto exit_put_device;
 557         }
 558
 559         usb_set_intfdata(usb_intf, hw);
 560
 561         rt2x00dev = hw->priv;
 562         rt2x00dev->dev = usb_intf;
 563         rt2x00dev->ops = ops;
 564         rt2x00dev->hw = hw;
 565         mutex_init(&rt2x00dev->usb_cache_mutex);
 566
 567         rt2x00dev->usb_maxpacket =
 568             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
 569         if (!rt2x00dev->usb_maxpacket)
 570                 rt2x00dev->usb_maxpacket = 1;
 571
 572         retval = rt2x00usb_alloc_reg(rt2x00dev);
 573         if (retval)
 574                 goto exit_free_device;
 575
 576         retval = rt2x00lib_probe_dev(rt2x00dev);
 577         if (retval)
 578                 goto exit_free_reg;
 579
 580         return 0;
 581
 582 exit_free_reg:
 583         rt2x00usb_free_reg(rt2x00dev);
 584
 585 exit_free_device:
 586         ieee80211_free_hw(hw);
 587
 588 exit_put_device:
 589         usb_put_dev(usb_dev);
 590
 591         usb_set_intfdata(usb_intf, NULL);
 592
 593         return retval;
 594 }
 595 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
 596
 597 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
 598 {
 599         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 600         struct rt2x00_dev *rt2x00dev = hw->priv;
 601
 602         /*
 603          * Free all allocated data.
 604          */
 605         rt2x00lib_remove_dev(rt2x00dev);
 606         rt2x00usb_free_reg(rt2x00dev);
 607         ieee80211_free_hw(hw);
 608
 609         /*
 610          * Free the USB device data.
 611          */
 612         usb_set_intfdata(usb_intf, NULL);
 613         usb_put_dev(interface_to_usbdev(usb_intf));
 614 }
 615 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
 616
 617 #ifdef CONFIG_PM
 618 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
 619 {
 620         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 621         struct rt2x00_dev *rt2x00dev = hw->priv;
 622         int retval;
 623
 624         retval = rt2x00lib_suspend(rt2x00dev, state);
 625         if (retval)
 626                 return retval;
 627
 628         rt2x00usb_free_reg(rt2x00dev);
 629
 630         /*
 631          * Decrease usbdev refcount.
 632          */
 633         usb_put_dev(interface_to_usbdev(usb_intf));
 634
 635         return 0;
 636 }
 637 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
 638
 639 int rt2x00usb_resume(struct usb_interface *usb_intf)
 640 {
 641         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 642         struct rt2x00_dev *rt2x00dev = hw->priv;
 643         int retval;
 644
 645         usb_get_dev(interface_to_usbdev(usb_intf));
 646
 647         retval = rt2x00usb_alloc_reg(rt2x00dev);
 648         if (retval)
 649                 return retval;
 650
 651         retval = rt2x00lib_resume(rt2x00dev);
 652         if (retval)
 653                 goto exit_free_reg;
 654
 655         return 0;
 656
 657 exit_free_reg:
 658         rt2x00usb_free_reg(rt2x00dev);
 659
 660         return retval;
 661 }
 662 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
 663 #endif /* CONFIG_PM */
 664
 665 /*
 666  * rt2x00usb module information.
 667  */
 668 MODULE_AUTHOR(DRV_PROJECT);
 669 MODULE_VERSION(DRV_VERSION);
 670 MODULE_DESCRIPTION("rt2x00 usb library");
 671 MODULE_LICENSE("GPL");