drivers/net/wireless/rt2x00/rt2x00usb.c

   1 /*
   2         Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
   3         Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
   4         <http://rt2x00.serialmonkey.com>
   5
   6         This program is free software; you can redistribute it and/or modify
   7         it under the terms of the GNU General Public License as published by
   8         the Free Software Foundation; either version 2 of the License, or
   9         (at your option) any later version.
  10
  11         This program is distributed in the hope that it will be useful,
  12         but WITHOUT ANY WARRANTY; without even the implied warranty of
  13         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14         GNU General Public License for more details.
  15
  16         You should have received a copy of the GNU General Public License
  17         along with this program; if not, write to the
  18         Free Software Foundation, Inc.,
  19         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 /*
  23         Module: rt2x00usb
  24         Abstract: rt2x00 generic usb device routines.
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/slab.h>
  30 #include <linux/usb.h>
  31 #include <linux/bug.h>
  32
  33 #include "rt2x00.h"
  34 #include "rt2x00usb.h"
  35
  36 /*
  37  * Interfacing with the HW.
  38  */
  39 int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
  40                              const u8 request, const u8 requesttype,
  41                              const u16 offset, const u16 value,
  42                              void *buffer, const u16 buffer_length,
  43                              const int timeout)
  44 {
  45         struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
  46         int status;
  47         unsigned int i;
  48         unsigned int pipe =
  49             (requesttype == USB_VENDOR_REQUEST_IN) ?
  50             usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
  51
  52         if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
  53                 return -ENODEV;
  54
  55         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
  56                 status = usb_control_msg(usb_dev, pipe, request, requesttype,
  57                                          value, offset, buffer, buffer_length,
  58                                          timeout);
  59                 if (status >= 0)
  60                         return 0;
  61
  62                 /*
  63                  * Check for errors
  64                  * -ENODEV: Device has disappeared, no point continuing.
  65                  * All other errors: Try again.
  66                  */
  67                 else if (status == -ENODEV) {
  68                         clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
  69                         break;
  70                 }
  71         }
  72
  73         ERROR(rt2x00dev,
  74               "Vendor Request 0x%02x failed for offset 0x%04x with error %d.\n",
  75               request, offset, status);
  76
  77         return status;
  78 }
  79 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
  80
  81 int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
  82                                    const u8 request, const u8 requesttype,
  83                                    const u16 offset, void *buffer,
  84                                    const u16 buffer_length, const int timeout)
  85 {
  86         int status;
  87
  88         BUG_ON(!mutex_is_locked(&rt2x00dev->csr_mutex));
  89
  90         /*
  91          * Check for Cache availability.
  92          */
  93         if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
  94                 ERROR(rt2x00dev, "CSR cache not available.\n");
  95                 return -ENOMEM;
  96         }
  97
  98         if (requesttype == USB_VENDOR_REQUEST_OUT)
  99                 memcpy(rt2x00dev->csr.cache, buffer, buffer_length);
 100
 101         status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
 102                                           offset, 0, rt2x00dev->csr.cache,
 103                                           buffer_length, timeout);
 104
 105         if (!status && requesttype == USB_VENDOR_REQUEST_IN)
 106                 memcpy(buffer, rt2x00dev->csr.cache, buffer_length);
 107
 108         return status;
 109 }
 110 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
 111
 112 int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
 113                                   const u8 request, const u8 requesttype,
 114                                   const u16 offset, void *buffer,
 115                                   const u16 buffer_length, const int timeout)
 116 {
 117         int status = 0;
 118         unsigned char *tb;
 119         u16 off, len, bsize;
 120
 121         mutex_lock(&rt2x00dev->csr_mutex);
 122
 123         tb  = (char *)buffer;
 124         off = offset;
 125         len = buffer_length;
 126         while (len && !status) {
 127                 bsize = min_t(u16, CSR_CACHE_SIZE, len);
 128                 status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
 129                                                         requesttype, off, tb,
 130                                                         bsize, timeout);
 131
 132                 tb  += bsize;
 133                 len -= bsize;
 134                 off += bsize;
 135         }
 136
 137         mutex_unlock(&rt2x00dev->csr_mutex);
 138
 139         return status;
 140 }
 141 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
 142
 143 int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
 144                            const unsigned int offset,
 145                            const struct rt2x00_field32 field,
 146                            u32 *reg)
 147 {
 148         unsigned int i;
 149
 150         if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
 151                 return -ENODEV;
 152
 153         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
 154                 rt2x00usb_register_read_lock(rt2x00dev, offset, reg);
 155                 if (!rt2x00_get_field32(*reg, field))
 156                         return 1;
 157                 udelay(REGISTER_BUSY_DELAY);
 158         }
 159
 160         ERROR(rt2x00dev, "Indirect register access failed: "
 161               "offset=0x%.08x, value=0x%.08x\n", offset, *reg);
 162         *reg = ~0;
 163
 164         return 0;
 165 }
 166 EXPORT_SYMBOL_GPL(rt2x00usb_regbusy_read);
 167
 168
 169 struct rt2x00_async_read_data {
 170         __le32 reg;
 171         struct usb_ctrlrequest cr;
 172         struct rt2x00_dev *rt2x00dev;
 173         bool (*callback)(struct rt2x00_dev *, int, u32);
 174 };
 175
 176 static void rt2x00usb_register_read_async_cb(struct urb *urb)
 177 {
 178         struct rt2x00_async_read_data *rd = urb->context;
 179         if (rd->callback(rd->rt2x00dev, urb->status, le32_to_cpu(rd->reg))) {
 180                 if (usb_submit_urb(urb, GFP_ATOMIC) < 0)
 181                         kfree(rd);
 182         } else
 183                 kfree(rd);
 184 }
 185
 186 void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
 187                                    const unsigned int offset,
 188                                    bool (*callback)(struct rt2x00_dev*, int, u32))
 189 {
 190         struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
 191         struct urb *urb;
 192         struct rt2x00_async_read_data *rd;
 193
 194         rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
 195         if (!rd)
 196                 return;
 197
 198         urb = usb_alloc_urb(0, GFP_ATOMIC);
 199         if (!urb) {
 200                 kfree(rd);
 201                 return;
 202         }
 203
 204         rd->rt2x00dev = rt2x00dev;
 205         rd->callback = callback;
 206         rd->cr.bRequestType = USB_VENDOR_REQUEST_IN;
 207         rd->cr.bRequest = USB_MULTI_READ;
 208         rd->cr.wValue = 0;
 209         rd->cr.wIndex = cpu_to_le16(offset);
 210         rd->cr.wLength = cpu_to_le16(sizeof(u32));
 211
 212         usb_fill_control_urb(urb, usb_dev, usb_rcvctrlpipe(usb_dev, 0),
 213                              (unsigned char *)(&rd->cr), &rd->reg, sizeof(rd->reg),
 214                              rt2x00usb_register_read_async_cb, rd);
 215         if (usb_submit_urb(urb, GFP_ATOMIC) < 0)
 216                 kfree(rd);
 217         usb_free_urb(urb);
 218 }
 219 EXPORT_SYMBOL_GPL(rt2x00usb_register_read_async);
 220
 221 /*
 222  * TX data handlers.
 223  */
 224 static void rt2x00usb_work_txdone_entry(struct queue_entry *entry)
 225 {
 226         /*
 227          * If the transfer to hardware succeeded, it does not mean the
 228          * frame was send out correctly. It only means the frame
 229          * was successfully pushed to the hardware, we have no
 230          * way to determine the transmission status right now.
 231          * (Only indirectly by looking at the failed TX counters
 232          * in the register).
 233          */
 234         if (test_bit(ENTRY_DATA_IO_FAILED, &entry->flags))
 235                 rt2x00lib_txdone_noinfo(entry, TXDONE_FAILURE);
 236         else
 237                 rt2x00lib_txdone_noinfo(entry, TXDONE_UNKNOWN);
 238 }
 239
 240 static void rt2x00usb_work_txdone(struct work_struct *work)
 241 {
 242         struct rt2x00_dev *rt2x00dev =
 243             container_of(work, struct rt2x00_dev, txdone_work);
 244         struct data_queue *queue;
 245         struct queue_entry *entry;
 246
 247         tx_queue_for_each(rt2x00dev, queue) {
 248                 while (!rt2x00queue_empty(queue)) {
 249                         entry = rt2x00queue_get_entry(queue, Q_INDEX_DONE);
 250
 251                         if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
 252                             !test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
 253                                 break;
 254
 255                         rt2x00usb_work_txdone_entry(entry);
 256                 }
 257         }
 258 }
 259
 260 static void rt2x00usb_interrupt_txdone(struct urb *urb)
 261 {
 262         struct queue_entry *entry = (struct queue_entry *)urb->context;
 263         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 264
 265         if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 266                 return;
 267         /*
 268          * Check if the frame was correctly uploaded
 269          */
 270         if (urb->status)
 271                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
 272         /*
 273          * Report the frame as DMA done
 274          */
 275         rt2x00lib_dmadone(entry);
 276
 277         if (rt2x00dev->ops->lib->tx_dma_done)
 278                 rt2x00dev->ops->lib->tx_dma_done(entry);
 279         /*
 280          * Schedule the delayed work for reading the TX status
 281          * from the device.
 282          */
 283         if (!test_bit(REQUIRE_TXSTATUS_FIFO, &rt2x00dev->cap_flags) ||
 284             !kfifo_is_empty(&rt2x00dev->txstatus_fifo))
 285                 queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work);
 286 }
 287
 288 static bool rt2x00usb_kick_tx_entry(struct queue_entry *entry, void* data)
 289 {
 290         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 291         struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
 292         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 293         u32 length;
 294         int status;
 295
 296         if (!test_and_clear_bit(ENTRY_DATA_PENDING, &entry->flags) ||
 297             test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
 298                 return false;
 299
 300         /*
 301          * USB devices cannot blindly pass the skb->len as the
 302          * length of the data to usb_fill_bulk_urb. Pass the skb
 303          * to the driver to determine what the length should be.
 304          */
 305         length = rt2x00dev->ops->lib->get_tx_data_len(entry);
 306
 307         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
 308                           usb_sndbulkpipe(usb_dev, entry->queue->usb_endpoint),
 309                           entry->skb->data, length,
 310                           rt2x00usb_interrupt_txdone, entry);
 311
 312         status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
 313         if (status) {
 314                 if (status == -ENODEV)
 315                         clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
 316                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
 317                 rt2x00lib_dmadone(entry);
 318         }
 319
 320         return false;
 321 }
 322
 323 /*
 324  * RX data handlers.
 325  */
 326 static void rt2x00usb_work_rxdone(struct work_struct *work)
 327 {
 328         struct rt2x00_dev *rt2x00dev =
 329             container_of(work, struct rt2x00_dev, rxdone_work);
 330         struct queue_entry *entry;
 331         struct skb_frame_desc *skbdesc;
 332         u8 rxd[32];
 333
 334         while (!rt2x00queue_empty(rt2x00dev->rx)) {
 335                 entry = rt2x00queue_get_entry(rt2x00dev->rx, Q_INDEX_DONE);
 336
 337                 if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
 338                     !test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
 339                         break;
 340
 341                 /*
 342                  * Fill in desc fields of the skb descriptor
 343                  */
 344                 skbdesc = get_skb_frame_desc(entry->skb);
 345                 skbdesc->desc = rxd;
 346                 skbdesc->desc_len = entry->queue->desc_size;
 347
 348                 /*
 349                  * Send the frame to rt2x00lib for further processing.
 350                  */
 351                 rt2x00lib_rxdone(entry);
 352         }
 353 }
 354
 355 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
 356 {
 357         struct queue_entry *entry = (struct queue_entry *)urb->context;
 358         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 359
 360         if (!test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 361                 return;
 362
 363         /*
 364          * Report the frame as DMA done
 365          */
 366         rt2x00lib_dmadone(entry);
 367
 368         /*
 369          * Check if the received data is simply too small
 370          * to be actually valid, or if the urb is signaling
 371          * a problem.
 372          */
 373         if (urb->actual_length < entry->queue->desc_size || urb->status)
 374                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
 375
 376         /*
 377          * Schedule the delayed work for reading the RX status
 378          * from the device.
 379          */
 380         queue_work(rt2x00dev->workqueue, &rt2x00dev->rxdone_work);
 381 }
 382
 383 static bool rt2x00usb_kick_rx_entry(struct queue_entry *entry, void* data)
 384 {
 385         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 386         struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
 387         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 388         int status;
 389
 390         if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
 391             test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
 392                 return false;
 393
 394         rt2x00lib_dmastart(entry);
 395
 396         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
 397                           usb_rcvbulkpipe(usb_dev, entry->queue->usb_endpoint),
 398                           entry->skb->data, entry->skb->len,
 399                           rt2x00usb_interrupt_rxdone, entry);
 400
 401         status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
 402         if (status) {
 403                 if (status == -ENODEV)
 404                         clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
 405                 set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
 406                 rt2x00lib_dmadone(entry);
 407         }
 408
 409         return false;
 410 }
 411
 412 void rt2x00usb_kick_queue(struct data_queue *queue)
 413 {
 414         switch (queue->qid) {
 415         case QID_AC_VO:
 416         case QID_AC_VI:
 417         case QID_AC_BE:
 418         case QID_AC_BK:
 419                 if (!rt2x00queue_empty(queue))
 420                         rt2x00queue_for_each_entry(queue,
 421                                                    Q_INDEX_DONE,
 422                                                    Q_INDEX,
 423                                                    NULL,
 424                                                    rt2x00usb_kick_tx_entry);
 425                 break;
 426         case QID_RX:
 427                 if (!rt2x00queue_full(queue))
 428                         rt2x00queue_for_each_entry(queue,
 429                                                    Q_INDEX_DONE,
 430                                                    Q_INDEX,
 431                                                    NULL,
 432                                                    rt2x00usb_kick_rx_entry);
 433                 break;
 434         default:
 435                 break;
 436         }
 437 }
 438 EXPORT_SYMBOL_GPL(rt2x00usb_kick_queue);
 439
 440 static bool rt2x00usb_flush_entry(struct queue_entry *entry, void* data)
 441 {
 442         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 443         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
 444         struct queue_entry_priv_usb_bcn *bcn_priv = entry->priv_data;
 445
 446         if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
 447                 return false;
 448
 449         usb_kill_urb(entry_priv->urb);
 450
 451         /*
 452          * Kill guardian urb (if required by driver).
 453          */
 454         if ((entry->queue->qid == QID_BEACON) &&
 455             (test_bit(REQUIRE_BEACON_GUARD, &rt2x00dev->cap_flags)))
 456                 usb_kill_urb(bcn_priv->guardian_urb);
 457
 458         return false;
 459 }
 460
 461 void rt2x00usb_flush_queue(struct data_queue *queue, bool drop)
 462 {
 463         struct work_struct *completion;
 464         unsigned int i;
 465
 466         if (drop)
 467                 rt2x00queue_for_each_entry(queue, Q_INDEX_DONE, Q_INDEX, NULL,
 468                                            rt2x00usb_flush_entry);
 469
 470         /*
 471          * Obtain the queue completion handler
 472          */
 473         switch (queue->qid) {
 474         case QID_AC_VO:
 475         case QID_AC_VI:
 476         case QID_AC_BE:
 477         case QID_AC_BK:
 478                 completion = &queue->rt2x00dev->txdone_work;
 479                 break;
 480         case QID_RX:
 481                 completion = &queue->rt2x00dev->rxdone_work;
 482                 break;
 483         default:
 484                 return;
 485         }
 486
 487         for (i = 0; i < 10; i++) {
 488                 /*
 489                  * Check if the driver is already done, otherwise we
 490                  * have to sleep a little while to give the driver/hw
 491                  * the oppurtunity to complete interrupt process itself.
 492                  */
 493                 if (rt2x00queue_empty(queue))
 494                         break;
 495
 496                 /*
 497                  * Schedule the completion handler manually, when this
 498                  * worker function runs, it should cleanup the queue.
 499                  */
 500                 queue_work(queue->rt2x00dev->workqueue, completion);
 501
 502                 /*
 503                  * Wait for a little while to give the driver
 504                  * the oppurtunity to recover itself.
 505                  */
 506                 msleep(10);
 507         }
 508 }
 509 EXPORT_SYMBOL_GPL(rt2x00usb_flush_queue);
 510
 511 static void rt2x00usb_watchdog_tx_dma(struct data_queue *queue)
 512 {
 513         WARNING(queue->rt2x00dev, "TX queue %d DMA timed out,"
 514                 " invoke forced forced reset\n", queue->qid);
 515
 516         rt2x00queue_flush_queue(queue, true);
 517 }
 518
 519 static void rt2x00usb_watchdog_tx_status(struct data_queue *queue)
 520 {
 521         WARNING(queue->rt2x00dev, "TX queue %d status timed out,"
 522                 " invoke forced tx handler\n", queue->qid);
 523
 524         queue_work(queue->rt2x00dev->workqueue, &queue->rt2x00dev->txdone_work);
 525 }
 526
 527 static int rt2x00usb_status_timeout(struct data_queue *queue)
 528 {
 529         struct queue_entry *entry;
 530
 531         entry = rt2x00queue_get_entry(queue, Q_INDEX_DONE);
 532         return rt2x00queue_status_timeout(entry);
 533 }
 534
 535 static int rt2x00usb_dma_timeout(struct data_queue *queue)
 536 {
 537         struct queue_entry *entry;
 538
 539         entry = rt2x00queue_get_entry(queue, Q_INDEX_DMA_DONE);
 540         return rt2x00queue_dma_timeout(entry);
 541 }
 542
 543 void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)
 544 {
 545         struct data_queue *queue;
 546
 547         tx_queue_for_each(rt2x00dev, queue) {
 548                 if (!rt2x00queue_empty(queue)) {
 549                         if (rt2x00usb_dma_timeout(queue))
 550                                 rt2x00usb_watchdog_tx_dma(queue);
 551                         if (rt2x00usb_status_timeout(queue))
 552                                 rt2x00usb_watchdog_tx_status(queue);
 553                 }
 554         }
 555 }
 556 EXPORT_SYMBOL_GPL(rt2x00usb_watchdog);
 557
 558 /*
 559  * Radio handlers
 560  */
 561 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 562 {
 563         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0, 0,
 564                                     REGISTER_TIMEOUT);
 565 }
 566 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
 567
 568 /*
 569  * Device initialization handlers.
 570  */
 571 void rt2x00usb_clear_entry(struct queue_entry *entry)
 572 {
 573         entry->flags = 0;
 574
 575         if (entry->queue->qid == QID_RX)
 576                 rt2x00usb_kick_rx_entry(entry, NULL);
 577 }
 578 EXPORT_SYMBOL_GPL(rt2x00usb_clear_entry);
 579
 580 static void rt2x00usb_assign_endpoint(struct data_queue *queue,
 581                                       struct usb_endpoint_descriptor *ep_desc)
 582 {
 583         struct usb_device *usb_dev = to_usb_device_intf(queue->rt2x00dev->dev);
 584         int pipe;
 585
 586         queue->usb_endpoint = usb_endpoint_num(ep_desc);
 587
 588         if (queue->qid == QID_RX) {
 589                 pipe = usb_rcvbulkpipe(usb_dev, queue->usb_endpoint);
 590                 queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe, 0);
 591         } else {
 592                 pipe = usb_sndbulkpipe(usb_dev, queue->usb_endpoint);
 593                 queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe, 1);
 594         }
 595
 596         if (!queue->usb_maxpacket)
 597                 queue->usb_maxpacket = 1;
 598 }
 599
 600 static int rt2x00usb_find_endpoints(struct rt2x00_dev *rt2x00dev)
 601 {
 602         struct usb_interface *intf = to_usb_interface(rt2x00dev->dev);
 603         struct usb_host_interface *intf_desc = intf->cur_altsetting;
 604         struct usb_endpoint_descriptor *ep_desc;
 605         struct data_queue *queue = rt2x00dev->tx;
 606         struct usb_endpoint_descriptor *tx_ep_desc = NULL;
 607         unsigned int i;
 608
 609         /*
 610          * Walk through all available endpoints to search for "bulk in"
 611          * and "bulk out" endpoints. When we find such endpoints collect
 612          * the information we need from the descriptor and assign it
 613          * to the queue.
 614          */
 615         for (i = 0; i < intf_desc->desc.bNumEndpoints; i++) {
 616                 ep_desc = &intf_desc->endpoint[i].desc;
 617
 618                 if (usb_endpoint_is_bulk_in(ep_desc)) {
 619                         rt2x00usb_assign_endpoint(rt2x00dev->rx, ep_desc);
 620                 } else if (usb_endpoint_is_bulk_out(ep_desc) &&
 621                            (queue != queue_end(rt2x00dev))) {
 622                         rt2x00usb_assign_endpoint(queue, ep_desc);
 623                         queue = queue_next(queue);
 624
 625                         tx_ep_desc = ep_desc;
 626                 }
 627         }
 628
 629         /*
 630          * At least 1 endpoint for RX and 1 endpoint for TX must be available.
 631          */
 632         if (!rt2x00dev->rx->usb_endpoint || !rt2x00dev->tx->usb_endpoint) {
 633                 ERROR(rt2x00dev, "Bulk-in/Bulk-out endpoints not found\n");
 634                 return -EPIPE;
 635         }
 636
 637         /*
 638          * It might be possible not all queues have a dedicated endpoint.
 639          * Loop through all TX queues and copy the endpoint information
 640          * which we have gathered from already assigned endpoints.
 641          */
 642         txall_queue_for_each(rt2x00dev, queue) {
 643                 if (!queue->usb_endpoint)
 644                         rt2x00usb_assign_endpoint(queue, tx_ep_desc);
 645         }
 646
 647         return 0;
 648 }
 649
 650 static int rt2x00usb_alloc_entries(struct data_queue *queue)
 651 {
 652         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 653         struct queue_entry_priv_usb *entry_priv;
 654         struct queue_entry_priv_usb_bcn *bcn_priv;
 655         unsigned int i;
 656
 657         for (i = 0; i < queue->limit; i++) {
 658                 entry_priv = queue->entries[i].priv_data;
 659                 entry_priv->urb = usb_alloc_urb(0, GFP_KERNEL);
 660                 if (!entry_priv->urb)
 661                         return -ENOMEM;
 662         }
 663
 664         /*
 665          * If this is not the beacon queue or
 666          * no guardian byte was required for the beacon,
 667          * then we are done.
 668          */
 669         if (queue->qid != QID_BEACON ||
 670             !test_bit(REQUIRE_BEACON_GUARD, &rt2x00dev->cap_flags))
 671                 return 0;
 672
 673         for (i = 0; i < queue->limit; i++) {
 674                 bcn_priv = queue->entries[i].priv_data;
 675                 bcn_priv->guardian_urb = usb_alloc_urb(0, GFP_KERNEL);
 676                 if (!bcn_priv->guardian_urb)
 677                         return -ENOMEM;
 678         }
 679
 680         return 0;
 681 }
 682
 683 static void rt2x00usb_free_entries(struct data_queue *queue)
 684 {
 685         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 686         struct queue_entry_priv_usb *entry_priv;
 687         struct queue_entry_priv_usb_bcn *bcn_priv;
 688         unsigned int i;
 689
 690         if (!queue->entries)
 691                 return;
 692
 693         for (i = 0; i < queue->limit; i++) {
 694                 entry_priv = queue->entries[i].priv_data;
 695                 usb_kill_urb(entry_priv->urb);
 696                 usb_free_urb(entry_priv->urb);
 697         }
 698
 699         /*
 700          * If this is not the beacon queue or
 701          * no guardian byte was required for the beacon,
 702          * then we are done.
 703          */
 704         if (queue->qid != QID_BEACON ||
 705             !test_bit(REQUIRE_BEACON_GUARD, &rt2x00dev->cap_flags))
 706                 return;
 707
 708         for (i = 0; i < queue->limit; i++) {
 709                 bcn_priv = queue->entries[i].priv_data;
 710                 usb_kill_urb(bcn_priv->guardian_urb);
 711                 usb_free_urb(bcn_priv->guardian_urb);
 712         }
 713 }
 714
 715 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
 716 {
 717         struct data_queue *queue;
 718         int status;
 719
 720         /*
 721          * Find endpoints for each queue
 722          */
 723         status = rt2x00usb_find_endpoints(rt2x00dev);
 724         if (status)
 725                 goto exit;
 726
 727         /*
 728          * Allocate DMA
 729          */
 730         queue_for_each(rt2x00dev, queue) {
 731                 status = rt2x00usb_alloc_entries(queue);
 732                 if (status)
 733                         goto exit;
 734         }
 735
 736         return 0;
 737
 738 exit:
 739         rt2x00usb_uninitialize(rt2x00dev);
 740
 741         return status;
 742 }
 743 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
 744
 745 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
 746 {
 747         struct data_queue *queue;
 748
 749         queue_for_each(rt2x00dev, queue)
 750                 rt2x00usb_free_entries(queue);
 751 }
 752 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
 753
 754 /*
 755  * USB driver handlers.
 756  */
 757 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
 758 {
 759         kfree(rt2x00dev->rf);
 760         rt2x00dev->rf = NULL;
 761
 762         kfree(rt2x00dev->eeprom);
 763         rt2x00dev->eeprom = NULL;
 764
 765         kfree(rt2x00dev->csr.cache);
 766         rt2x00dev->csr.cache = NULL;
 767 }
 768
 769 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
 770 {
 771         rt2x00dev->csr.cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
 772         if (!rt2x00dev->csr.cache)
 773                 goto exit;
 774
 775         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
 776         if (!rt2x00dev->eeprom)
 777                 goto exit;
 778
 779         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
 780         if (!rt2x00dev->rf)
 781                 goto exit;
 782
 783         return 0;
 784
 785 exit:
 786         ERROR_PROBE("Failed to allocate registers.\n");
 787
 788         rt2x00usb_free_reg(rt2x00dev);
 789
 790         return -ENOMEM;
 791 }
 792
 793 int rt2x00usb_probe(struct usb_interface *usb_intf,
 794                     const struct rt2x00_ops *ops)
 795 {
 796         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
 797         struct ieee80211_hw *hw;
 798         struct rt2x00_dev *rt2x00dev;
 799         int retval;
 800
 801         usb_dev = usb_get_dev(usb_dev);
 802         usb_reset_device(usb_dev);
 803
 804         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
 805         if (!hw) {
 806                 ERROR_PROBE("Failed to allocate hardware.\n");
 807                 retval = -ENOMEM;
 808                 goto exit_put_device;
 809         }
 810
 811         usb_set_intfdata(usb_intf, hw);
 812
 813         rt2x00dev = hw->priv;
 814         rt2x00dev->dev = &usb_intf->dev;
 815         rt2x00dev->ops = ops;
 816         rt2x00dev->hw = hw;
 817
 818         rt2x00_set_chip_intf(rt2x00dev, RT2X00_CHIP_INTF_USB);
 819
 820         INIT_WORK(&rt2x00dev->rxdone_work, rt2x00usb_work_rxdone);
 821         INIT_WORK(&rt2x00dev->txdone_work, rt2x00usb_work_txdone);
 822         init_timer(&rt2x00dev->txstatus_timer);
 823
 824         retval = rt2x00usb_alloc_reg(rt2x00dev);
 825         if (retval)
 826                 goto exit_free_device;
 827
 828         retval = rt2x00lib_probe_dev(rt2x00dev);
 829         if (retval)
 830                 goto exit_free_reg;
 831
 832         return 0;
 833
 834 exit_free_reg:
 835         rt2x00usb_free_reg(rt2x00dev);
 836
 837 exit_free_device:
 838         ieee80211_free_hw(hw);
 839
 840 exit_put_device:
 841         usb_put_dev(usb_dev);
 842
 843         usb_set_intfdata(usb_intf, NULL);
 844
 845         return retval;
 846 }
 847 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
 848
 849 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
 850 {
 851         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 852         struct rt2x00_dev *rt2x00dev = hw->priv;
 853
 854         /*
 855          * Free all allocated data.
 856          */
 857         rt2x00lib_remove_dev(rt2x00dev);
 858         rt2x00usb_free_reg(rt2x00dev);
 859         ieee80211_free_hw(hw);
 860
 861         /*
 862          * Free the USB device data.
 863          */
 864         usb_set_intfdata(usb_intf, NULL);
 865         usb_put_dev(interface_to_usbdev(usb_intf));
 866 }
 867 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
 868
 869 #ifdef CONFIG_PM
 870 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
 871 {
 872         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 873         struct rt2x00_dev *rt2x00dev = hw->priv;
 874
 875         return rt2x00lib_suspend(rt2x00dev, state);
 876 }
 877 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
 878
 879 int rt2x00usb_resume(struct usb_interface *usb_intf)
 880 {
 881         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 882         struct rt2x00_dev *rt2x00dev = hw->priv;
 883
 884         return rt2x00lib_resume(rt2x00dev);
 885 }
 886 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
 887 #endif /* CONFIG_PM */
 888
 889 /*
 890  * rt2x00usb module information.
 891  */
 892 MODULE_AUTHOR(DRV_PROJECT);
 893 MODULE_VERSION(DRV_VERSION);
 894 MODULE_DESCRIPTION("rt2x00 usb library");
 895 MODULE_LICENSE("GPL");