drivers/net/wireless/rt2x00/rt2x00usb.c

   1 /*
   2         Copyright (C) 2004 - 2007 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(rt2x00dev_usb(rt2x00dev));
  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 data_entry *entry = (struct data_entry *)urb->context;
 132         struct data_ring *ring = entry->ring;
 133         struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
 134         __le32 *txd = (__le32 *)entry->skb->data;
 135         u32 word;
 136         int tx_status;
 137
 138         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 139             !__test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
 140                 return;
 141
 142         rt2x00_desc_read(txd, 0, &word);
 143
 144         /*
 145          * Remove the descriptor data from the buffer.
 146          */
 147         skb_pull(entry->skb, ring->desc_size);
 148
 149         /*
 150          * Obtain the status about this packet.
 151          */
 152         tx_status = !urb->status ? TX_SUCCESS : TX_FAIL_RETRY;
 153
 154         rt2x00lib_txdone(entry, tx_status, 0);
 155
 156         /*
 157          * Make this entry available for reuse.
 158          */
 159         entry->flags = 0;
 160         rt2x00_ring_index_done_inc(entry->ring);
 161
 162         /*
 163          * If the data ring was full before the txdone handler
 164          * we must make sure the packet queue in the mac80211 stack
 165          * is reenabled when the txdone handler has finished.
 166          */
 167         if (!rt2x00_ring_full(ring))
 168                 ieee80211_wake_queue(rt2x00dev->hw,
 169                                      entry->tx_status.control.queue);
 170 }
 171
 172 int rt2x00usb_write_tx_data(struct rt2x00_dev *rt2x00dev,
 173                             struct data_ring *ring, struct sk_buff *skb,
 174                             struct ieee80211_tx_control *control)
 175 {
 176         struct usb_device *usb_dev =
 177             interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
 178         struct data_entry *entry = rt2x00_get_data_entry(ring);
 179         struct skb_desc *desc;
 180         u32 length;
 181
 182         if (rt2x00_ring_full(ring))
 183                 return -EINVAL;
 184
 185         if (test_bit(ENTRY_OWNER_NIC, &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, ring->desc_size);
 197         memset(skb->data, 0, ring->desc_size);
 198
 199         /*
 200          * Fill in skb descriptor
 201          */
 202         desc = get_skb_desc(skb);
 203         desc->desc_len = ring->desc_size;
 204         desc->data_len = skb->len - ring->desc_size;
 205         desc->desc = skb->data;
 206         desc->data = skb->data + ring->desc_size;
 207         desc->ring = ring;
 208         desc->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_NIC, &entry->flags);
 223         usb_fill_bulk_urb(entry->priv, usb_dev, usb_sndbulkpipe(usb_dev, 1),
 224                           skb->data, length, rt2x00usb_interrupt_txdone, entry);
 225         usb_submit_urb(entry->priv, GFP_ATOMIC);
 226
 227         rt2x00_ring_index_inc(ring);
 228
 229         return 0;
 230 }
 231 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
 232
 233 /*
 234  * RX data handlers.
 235  */
 236 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
 237 {
 238         struct data_entry *entry = (struct data_entry *)urb->context;
 239         struct data_ring *ring = entry->ring;
 240         struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
 241         struct sk_buff *skb;
 242         struct ieee80211_hdr *hdr;
 243         struct skb_desc *skbdesc;
 244         struct rxdata_entry_desc desc;
 245         int header_size;
 246         int frame_size;
 247
 248         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 249             !test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
 250                 return;
 251
 252         /*
 253          * Check if the received data is simply too small
 254          * to be actually valid, or if the urb is signaling
 255          * a problem.
 256          */
 257         if (urb->actual_length < entry->ring->desc_size || urb->status)
 258                 goto skip_entry;
 259
 260         /*
 261          * Fill in skb descriptor
 262          */
 263         skbdesc = get_skb_desc(entry->skb);
 264         skbdesc->ring = ring;
 265         skbdesc->entry = entry;
 266
 267         memset(&desc, 0, sizeof(desc));
 268         rt2x00dev->ops->lib->fill_rxdone(entry, &desc);
 269
 270         /*
 271          * Allocate a new sk buffer to replace the current one.
 272          * If allocation fails, we should drop the current frame
 273          * so we can recycle the existing sk buffer for the new frame.
 274          * As alignment we use 2 and not NET_IP_ALIGN because we need
 275          * to be sure we have 2 bytes room in the head. (NET_IP_ALIGN
 276          * can be 0 on some hardware). We use these 2 bytes for frame
 277          * alignment later, we assume that the chance that
 278          * header_size % 4 == 2 is bigger then header_size % 2 == 0
 279          * and thus optimize alignment by reserving the 2 bytes in
 280          * advance.
 281          */
 282         frame_size = entry->ring->data_size + entry->ring->desc_size;
 283         skb = dev_alloc_skb(frame_size + 2);
 284         if (!skb)
 285                 goto skip_entry;
 286
 287         skb_reserve(skb, 2);
 288         skb_put(skb, frame_size);
 289
 290         /*
 291          * The data behind the ieee80211 header must be
 292          * aligned on a 4 byte boundary.
 293          */
 294         hdr = (struct ieee80211_hdr *)entry->skb->data;
 295         header_size =
 296             ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
 297
 298         if (header_size % 4 == 0) {
 299                 skb_push(entry->skb, 2);
 300                 memmove(entry->skb->data, entry->skb->data + 2, skb->len - 2);
 301         }
 302
 303         /*
 304          * Trim the entire buffer down to only contain the valid frame data
 305          * excluding the device descriptor. The position of the descriptor
 306          * varies. This means that we should check where the descriptor is
 307          * and decide if we need to pull the data pointer to exclude the
 308          * device descriptor.
 309          */
 310         if (skbdesc->data > skbdesc->desc)
 311                 skb_pull(entry->skb, skbdesc->desc_len);
 312         skb_trim(entry->skb, desc.size);
 313
 314         /*
 315          * Send the frame to rt2x00lib for further processing.
 316          */
 317         rt2x00lib_rxdone(entry, entry->skb, &desc);
 318
 319         /*
 320          * Replace current entry's skb with the newly allocated one,
 321          * and reinitialize the urb.
 322          */
 323         entry->skb = skb;
 324         urb->transfer_buffer = entry->skb->data;
 325         urb->transfer_buffer_length = entry->skb->len;
 326
 327 skip_entry:
 328         if (test_bit(DEVICE_ENABLED_RADIO, &ring->rt2x00dev->flags)) {
 329                 __set_bit(ENTRY_OWNER_NIC, &entry->flags);
 330                 usb_submit_urb(urb, GFP_ATOMIC);
 331         }
 332
 333         rt2x00_ring_index_inc(ring);
 334 }
 335
 336 /*
 337  * Radio handlers
 338  */
 339 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 340 {
 341         struct data_ring *ring;
 342         unsigned int i;
 343
 344         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0x0000, 0x0000,
 345                                     REGISTER_TIMEOUT);
 346
 347         /*
 348          * Cancel all rings.
 349          */
 350         ring_for_each(rt2x00dev, ring) {
 351                 for (i = 0; i < ring->stats.limit; i++)
 352                         usb_kill_urb(ring->entry[i].priv);
 353         }
 354 }
 355 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
 356
 357 /*
 358  * Device initialization handlers.
 359  */
 360 void rt2x00usb_init_rxentry(struct rt2x00_dev *rt2x00dev,
 361                             struct data_entry *entry)
 362 {
 363         struct usb_device *usb_dev =
 364              interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
 365
 366         usb_fill_bulk_urb(entry->priv, usb_dev,
 367                           usb_rcvbulkpipe(usb_dev, 1),
 368                           entry->skb->data, entry->skb->len,
 369                           rt2x00usb_interrupt_rxdone, entry);
 370
 371         __set_bit(ENTRY_OWNER_NIC, &entry->flags);
 372         usb_submit_urb(entry->priv, GFP_ATOMIC);
 373 }
 374 EXPORT_SYMBOL_GPL(rt2x00usb_init_rxentry);
 375
 376 void rt2x00usb_init_txentry(struct rt2x00_dev *rt2x00dev,
 377                             struct data_entry *entry)
 378 {
 379         entry->flags = 0;
 380 }
 381 EXPORT_SYMBOL_GPL(rt2x00usb_init_txentry);
 382
 383 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
 384                                struct data_ring *ring)
 385 {
 386         unsigned int i;
 387
 388         /*
 389          * Allocate the URB's
 390          */
 391         for (i = 0; i < ring->stats.limit; i++) {
 392                 ring->entry[i].priv = usb_alloc_urb(0, GFP_KERNEL);
 393                 if (!ring->entry[i].priv)
 394                         return -ENOMEM;
 395         }
 396
 397         return 0;
 398 }
 399
 400 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
 401                                struct data_ring *ring)
 402 {
 403         unsigned int i;
 404
 405         if (!ring->entry)
 406                 return;
 407
 408         for (i = 0; i < ring->stats.limit; i++) {
 409                 usb_kill_urb(ring->entry[i].priv);
 410                 usb_free_urb(ring->entry[i].priv);
 411                 if (ring->entry[i].skb)
 412                         kfree_skb(ring->entry[i].skb);
 413         }
 414 }
 415
 416 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
 417 {
 418         struct data_ring *ring;
 419         struct sk_buff *skb;
 420         unsigned int entry_size;
 421         unsigned int i;
 422         int uninitialized_var(status);
 423
 424         /*
 425          * Allocate DMA
 426          */
 427         ring_for_each(rt2x00dev, ring) {
 428                 status = rt2x00usb_alloc_urb(rt2x00dev, ring);
 429                 if (status)
 430                         goto exit;
 431         }
 432
 433         /*
 434          * For the RX ring, skb's should be allocated.
 435          */
 436         entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
 437         for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
 438                 skb = dev_alloc_skb(NET_IP_ALIGN + entry_size);
 439                 if (!skb)
 440                         goto exit;
 441
 442                 skb_reserve(skb, NET_IP_ALIGN);
 443                 skb_put(skb, entry_size);
 444
 445                 rt2x00dev->rx->entry[i].skb = skb;
 446         }
 447
 448         return 0;
 449
 450 exit:
 451         rt2x00usb_uninitialize(rt2x00dev);
 452
 453         return status;
 454 }
 455 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
 456
 457 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
 458 {
 459         struct data_ring *ring;
 460
 461         ring_for_each(rt2x00dev, ring)
 462                 rt2x00usb_free_urb(rt2x00dev, ring);
 463 }
 464 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
 465
 466 /*
 467  * USB driver handlers.
 468  */
 469 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
 470 {
 471         kfree(rt2x00dev->rf);
 472         rt2x00dev->rf = NULL;
 473
 474         kfree(rt2x00dev->eeprom);
 475         rt2x00dev->eeprom = NULL;
 476
 477         kfree(rt2x00dev->csr_cache);
 478         rt2x00dev->csr_cache = NULL;
 479 }
 480
 481 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
 482 {
 483         rt2x00dev->csr_cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
 484         if (!rt2x00dev->csr_cache)
 485                 goto exit;
 486
 487         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
 488         if (!rt2x00dev->eeprom)
 489                 goto exit;
 490
 491         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
 492         if (!rt2x00dev->rf)
 493                 goto exit;
 494
 495         return 0;
 496
 497 exit:
 498         ERROR_PROBE("Failed to allocate registers.\n");
 499
 500         rt2x00usb_free_reg(rt2x00dev);
 501
 502         return -ENOMEM;
 503 }
 504
 505 int rt2x00usb_probe(struct usb_interface *usb_intf,
 506                     const struct usb_device_id *id)
 507 {
 508         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
 509         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
 510         struct ieee80211_hw *hw;
 511         struct rt2x00_dev *rt2x00dev;
 512         int retval;
 513
 514         usb_dev = usb_get_dev(usb_dev);
 515
 516         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
 517         if (!hw) {
 518                 ERROR_PROBE("Failed to allocate hardware.\n");
 519                 retval = -ENOMEM;
 520                 goto exit_put_device;
 521         }
 522
 523         usb_set_intfdata(usb_intf, hw);
 524
 525         rt2x00dev = hw->priv;
 526         rt2x00dev->dev = usb_intf;
 527         rt2x00dev->ops = ops;
 528         rt2x00dev->hw = hw;
 529         mutex_init(&rt2x00dev->usb_cache_mutex);
 530
 531         rt2x00dev->usb_maxpacket =
 532             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
 533         if (!rt2x00dev->usb_maxpacket)
 534                 rt2x00dev->usb_maxpacket = 1;
 535
 536         retval = rt2x00usb_alloc_reg(rt2x00dev);
 537         if (retval)
 538                 goto exit_free_device;
 539
 540         retval = rt2x00lib_probe_dev(rt2x00dev);
 541         if (retval)
 542                 goto exit_free_reg;
 543
 544         return 0;
 545
 546 exit_free_reg:
 547         rt2x00usb_free_reg(rt2x00dev);
 548
 549 exit_free_device:
 550         ieee80211_free_hw(hw);
 551
 552 exit_put_device:
 553         usb_put_dev(usb_dev);
 554
 555         usb_set_intfdata(usb_intf, NULL);
 556
 557         return retval;
 558 }
 559 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
 560
 561 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
 562 {
 563         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 564         struct rt2x00_dev *rt2x00dev = hw->priv;
 565
 566         /*
 567          * Free all allocated data.
 568          */
 569         rt2x00lib_remove_dev(rt2x00dev);
 570         rt2x00usb_free_reg(rt2x00dev);
 571         ieee80211_free_hw(hw);
 572
 573         /*
 574          * Free the USB device data.
 575          */
 576         usb_set_intfdata(usb_intf, NULL);
 577         usb_put_dev(interface_to_usbdev(usb_intf));
 578 }
 579 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
 580
 581 #ifdef CONFIG_PM
 582 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
 583 {
 584         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 585         struct rt2x00_dev *rt2x00dev = hw->priv;
 586         int retval;
 587
 588         retval = rt2x00lib_suspend(rt2x00dev, state);
 589         if (retval)
 590                 return retval;
 591
 592         rt2x00usb_free_reg(rt2x00dev);
 593
 594         /*
 595          * Decrease usbdev refcount.
 596          */
 597         usb_put_dev(interface_to_usbdev(usb_intf));
 598
 599         return 0;
 600 }
 601 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
 602
 603 int rt2x00usb_resume(struct usb_interface *usb_intf)
 604 {
 605         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 606         struct rt2x00_dev *rt2x00dev = hw->priv;
 607         int retval;
 608
 609         usb_get_dev(interface_to_usbdev(usb_intf));
 610
 611         retval = rt2x00usb_alloc_reg(rt2x00dev);
 612         if (retval)
 613                 return retval;
 614
 615         retval = rt2x00lib_resume(rt2x00dev);
 616         if (retval)
 617                 goto exit_free_reg;
 618
 619         return 0;
 620
 621 exit_free_reg:
 622         rt2x00usb_free_reg(rt2x00dev);
 623
 624         return retval;
 625 }
 626 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
 627 #endif /* CONFIG_PM */
 628
 629 /*
 630  * rt2x00pci module information.
 631  */
 632 MODULE_AUTHOR(DRV_PROJECT);
 633 MODULE_VERSION(DRV_VERSION);
 634 MODULE_DESCRIPTION("rt2x00 library");
 635 MODULE_LICENSE("GPL");