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                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 184                 return -EINVAL;
 185         }
 186
 187         if (test_bit(ENTRY_OWNER_NIC, &entry->flags)) {
 188                 ERROR(rt2x00dev,
 189                       "Arrived at non-free entry in the non-full queue %d.\n"
 190                       "Please file bug report to %s.\n",
 191                       control->queue, DRV_PROJECT);
 192                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 193                 return -EINVAL;
 194         }
 195
 196         /*
 197          * Add the descriptor in front of the skb.
 198          */
 199         skb_push(skb, ring->desc_size);
 200         memset(skb->data, 0, ring->desc_size);
 201
 202         /*
 203          * Fill in skb descriptor
 204          */
 205         desc = get_skb_desc(skb);
 206         desc->desc_len = ring->desc_size;
 207         desc->data_len = skb->len - ring->desc_size;
 208         desc->desc = skb->data;
 209         desc->data = skb->data + ring->desc_size;
 210         desc->ring = ring;
 211         desc->entry = entry;
 212
 213         rt2x00lib_write_tx_desc(rt2x00dev, skb, control);
 214
 215         /*
 216          * USB devices cannot blindly pass the skb->len as the
 217          * length of the data to usb_fill_bulk_urb. Pass the skb
 218          * to the driver to determine what the length should be.
 219          */
 220         length = rt2x00dev->ops->lib->get_tx_data_len(rt2x00dev, skb);
 221
 222         /*
 223          * Initialize URB and send the frame to the device.
 224          */
 225         __set_bit(ENTRY_OWNER_NIC, &entry->flags);
 226         usb_fill_bulk_urb(entry->priv, usb_dev, usb_sndbulkpipe(usb_dev, 1),
 227                           skb->data, length, rt2x00usb_interrupt_txdone, entry);
 228         usb_submit_urb(entry->priv, GFP_ATOMIC);
 229
 230         rt2x00_ring_index_inc(ring);
 231
 232         if (rt2x00_ring_full(ring))
 233                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 234
 235         return 0;
 236 }
 237 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
 238
 239 /*
 240  * RX data handlers.
 241  */
 242 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
 243 {
 244         struct data_entry *entry = (struct data_entry *)urb->context;
 245         struct data_ring *ring = entry->ring;
 246         struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
 247         struct sk_buff *skb;
 248         struct ieee80211_hdr *hdr;
 249         struct skb_desc *skbdesc;
 250         struct rxdata_entry_desc desc;
 251         int header_size;
 252         int frame_size;
 253
 254         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
 255             !test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
 256                 return;
 257
 258         /*
 259          * Check if the received data is simply too small
 260          * to be actually valid, or if the urb is signaling
 261          * a problem.
 262          */
 263         if (urb->actual_length < entry->ring->desc_size || urb->status)
 264                 goto skip_entry;
 265
 266         memset(&desc, 0, sizeof(desc));
 267         rt2x00dev->ops->lib->fill_rxdone(entry, &desc);
 268
 269         /*
 270          * Allocate a new sk buffer to replace the current one.
 271          * If allocation fails, we should drop the current frame
 272          * so we can recycle the existing sk buffer for the new frame.
 273          * As alignment we use 2 and not NET_IP_ALIGN because we need
 274          * to be sure we have 2 bytes room in the head. (NET_IP_ALIGN
 275          * can be 0 on some hardware). We use these 2 bytes for frame
 276          * alignment later, we assume that the chance that
 277          * header_size % 4 == 2 is bigger then header_size % 2 == 0
 278          * and thus optimize alignment by reserving the 2 bytes in
 279          * advance.
 280          */
 281         frame_size = entry->ring->data_size + entry->ring->desc_size;
 282         skb = dev_alloc_skb(frame_size + 2);
 283         if (!skb)
 284                 goto skip_entry;
 285
 286         skb_reserve(skb, 2);
 287         skb_put(skb, frame_size);
 288
 289         /*
 290          * The data behind the ieee80211 header must be
 291          * aligned on a 4 byte boundary.
 292          * After that trim the entire buffer down to only
 293          * contain the valid frame data excluding the device
 294          * descriptor.
 295          */
 296         hdr = (struct ieee80211_hdr *)entry->skb->data;
 297         header_size =
 298             ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
 299
 300         if (header_size % 4 == 0) {
 301                 skb_push(entry->skb, 2);
 302                 memmove(entry->skb->data, entry->skb->data + 2, skb->len - 2);
 303         }
 304         skb_trim(entry->skb, desc.size);
 305
 306         /*
 307          * Fill in skb descriptor
 308          */
 309         skbdesc = get_skb_desc(entry->skb);
 310         skbdesc->desc_len = entry->ring->desc_size;
 311         skbdesc->data_len = entry->skb->len;
 312         skbdesc->desc = entry->skb->data - skbdesc->desc_len;
 313         skbdesc->data = entry->skb->data;
 314         skbdesc->ring = ring;
 315         skbdesc->entry = entry;
 316
 317         /*
 318          * Send the frame to rt2x00lib for further processing.
 319          */
 320         rt2x00lib_rxdone(entry, entry->skb, &desc);
 321
 322         /*
 323          * Replace current entry's skb with the newly allocated one,
 324          * and reinitialize the urb.
 325          */
 326         entry->skb = skb;
 327         urb->transfer_buffer = entry->skb->data;
 328         urb->transfer_buffer_length = entry->skb->len;
 329
 330 skip_entry:
 331         if (test_bit(DEVICE_ENABLED_RADIO, &ring->rt2x00dev->flags)) {
 332                 __set_bit(ENTRY_OWNER_NIC, &entry->flags);
 333                 usb_submit_urb(urb, GFP_ATOMIC);
 334         }
 335
 336         rt2x00_ring_index_inc(ring);
 337 }
 338
 339 /*
 340  * Radio handlers
 341  */
 342 void rt2x00usb_enable_radio(struct rt2x00_dev *rt2x00dev)
 343 {
 344         struct usb_device *usb_dev =
 345             interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
 346         struct data_ring *ring;
 347         struct data_entry *entry;
 348         unsigned int i;
 349
 350         /*
 351          * Initialize the TX rings
 352          */
 353         txringall_for_each(rt2x00dev, ring) {
 354                 for (i = 0; i < ring->stats.limit; i++)
 355                         ring->entry[i].flags = 0;
 356
 357                 rt2x00_ring_index_clear(ring);
 358         }
 359
 360         /*
 361          * Initialize and start the RX ring.
 362          */
 363         rt2x00_ring_index_clear(rt2x00dev->rx);
 364
 365         for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
 366                 entry = &rt2x00dev->rx->entry[i];
 367
 368                 usb_fill_bulk_urb(entry->priv, usb_dev,
 369                                   usb_rcvbulkpipe(usb_dev, 1),
 370                                   entry->skb->data, entry->skb->len,
 371                                   rt2x00usb_interrupt_rxdone, entry);
 372
 373                 __set_bit(ENTRY_OWNER_NIC, &entry->flags);
 374                 usb_submit_urb(entry->priv, GFP_ATOMIC);
 375         }
 376 }
 377 EXPORT_SYMBOL_GPL(rt2x00usb_enable_radio);
 378
 379 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
 380 {
 381         struct data_ring *ring;
 382         unsigned int i;
 383
 384         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0x0000, 0x0000,
 385                                     REGISTER_TIMEOUT);
 386
 387         /*
 388          * Cancel all rings.
 389          */
 390         ring_for_each(rt2x00dev, ring) {
 391                 for (i = 0; i < ring->stats.limit; i++)
 392                         usb_kill_urb(ring->entry[i].priv);
 393         }
 394 }
 395 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
 396
 397 /*
 398  * Device initialization handlers.
 399  */
 400 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
 401                                struct data_ring *ring)
 402 {
 403         unsigned int i;
 404
 405         /*
 406          * Allocate the URB's
 407          */
 408         for (i = 0; i < ring->stats.limit; i++) {
 409                 ring->entry[i].priv = usb_alloc_urb(0, GFP_KERNEL);
 410                 if (!ring->entry[i].priv)
 411                         return -ENOMEM;
 412         }
 413
 414         return 0;
 415 }
 416
 417 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
 418                                struct data_ring *ring)
 419 {
 420         unsigned int i;
 421
 422         if (!ring->entry)
 423                 return;
 424
 425         for (i = 0; i < ring->stats.limit; i++) {
 426                 usb_kill_urb(ring->entry[i].priv);
 427                 usb_free_urb(ring->entry[i].priv);
 428                 if (ring->entry[i].skb)
 429                         kfree_skb(ring->entry[i].skb);
 430         }
 431 }
 432
 433 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
 434 {
 435         struct data_ring *ring;
 436         struct sk_buff *skb;
 437         unsigned int entry_size;
 438         unsigned int i;
 439         int status;
 440
 441         /*
 442          * Allocate DMA
 443          */
 444         ring_for_each(rt2x00dev, ring) {
 445                 status = rt2x00usb_alloc_urb(rt2x00dev, ring);
 446                 if (status)
 447                         goto exit;
 448         }
 449
 450         /*
 451          * For the RX ring, skb's should be allocated.
 452          */
 453         entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
 454         for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
 455                 skb = dev_alloc_skb(NET_IP_ALIGN + entry_size);
 456                 if (!skb)
 457                         goto exit;
 458
 459                 skb_reserve(skb, NET_IP_ALIGN);
 460                 skb_put(skb, entry_size);
 461
 462                 rt2x00dev->rx->entry[i].skb = skb;
 463         }
 464
 465         return 0;
 466
 467 exit:
 468         rt2x00usb_uninitialize(rt2x00dev);
 469
 470         return status;
 471 }
 472 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
 473
 474 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
 475 {
 476         struct data_ring *ring;
 477
 478         ring_for_each(rt2x00dev, ring)
 479                 rt2x00usb_free_urb(rt2x00dev, ring);
 480 }
 481 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
 482
 483 /*
 484  * USB driver handlers.
 485  */
 486 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
 487 {
 488         kfree(rt2x00dev->rf);
 489         rt2x00dev->rf = NULL;
 490
 491         kfree(rt2x00dev->eeprom);
 492         rt2x00dev->eeprom = NULL;
 493
 494         kfree(rt2x00dev->csr_cache);
 495         rt2x00dev->csr_cache = NULL;
 496 }
 497
 498 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
 499 {
 500         rt2x00dev->csr_cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
 501         if (!rt2x00dev->csr_cache)
 502                 goto exit;
 503
 504         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
 505         if (!rt2x00dev->eeprom)
 506                 goto exit;
 507
 508         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
 509         if (!rt2x00dev->rf)
 510                 goto exit;
 511
 512         return 0;
 513
 514 exit:
 515         ERROR_PROBE("Failed to allocate registers.\n");
 516
 517         rt2x00usb_free_reg(rt2x00dev);
 518
 519         return -ENOMEM;
 520 }
 521
 522 int rt2x00usb_probe(struct usb_interface *usb_intf,
 523                     const struct usb_device_id *id)
 524 {
 525         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
 526         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
 527         struct ieee80211_hw *hw;
 528         struct rt2x00_dev *rt2x00dev;
 529         int retval;
 530
 531         usb_dev = usb_get_dev(usb_dev);
 532
 533         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
 534         if (!hw) {
 535                 ERROR_PROBE("Failed to allocate hardware.\n");
 536                 retval = -ENOMEM;
 537                 goto exit_put_device;
 538         }
 539
 540         usb_set_intfdata(usb_intf, hw);
 541
 542         rt2x00dev = hw->priv;
 543         rt2x00dev->dev = usb_intf;
 544         rt2x00dev->ops = ops;
 545         rt2x00dev->hw = hw;
 546         mutex_init(&rt2x00dev->usb_cache_mutex);
 547
 548         rt2x00dev->usb_maxpacket =
 549             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
 550         if (!rt2x00dev->usb_maxpacket)
 551                 rt2x00dev->usb_maxpacket = 1;
 552
 553         retval = rt2x00usb_alloc_reg(rt2x00dev);
 554         if (retval)
 555                 goto exit_free_device;
 556
 557         retval = rt2x00lib_probe_dev(rt2x00dev);
 558         if (retval)
 559                 goto exit_free_reg;
 560
 561         return 0;
 562
 563 exit_free_reg:
 564         rt2x00usb_free_reg(rt2x00dev);
 565
 566 exit_free_device:
 567         ieee80211_free_hw(hw);
 568
 569 exit_put_device:
 570         usb_put_dev(usb_dev);
 571
 572         usb_set_intfdata(usb_intf, NULL);
 573
 574         return retval;
 575 }
 576 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
 577
 578 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
 579 {
 580         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 581         struct rt2x00_dev *rt2x00dev = hw->priv;
 582
 583         /*
 584          * Free all allocated data.
 585          */
 586         rt2x00lib_remove_dev(rt2x00dev);
 587         rt2x00usb_free_reg(rt2x00dev);
 588         ieee80211_free_hw(hw);
 589
 590         /*
 591          * Free the USB device data.
 592          */
 593         usb_set_intfdata(usb_intf, NULL);
 594         usb_put_dev(interface_to_usbdev(usb_intf));
 595 }
 596 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
 597
 598 #ifdef CONFIG_PM
 599 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
 600 {
 601         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 602         struct rt2x00_dev *rt2x00dev = hw->priv;
 603         int retval;
 604
 605         retval = rt2x00lib_suspend(rt2x00dev, state);
 606         if (retval)
 607                 return retval;
 608
 609         rt2x00usb_free_reg(rt2x00dev);
 610
 611         /*
 612          * Decrease usbdev refcount.
 613          */
 614         usb_put_dev(interface_to_usbdev(usb_intf));
 615
 616         return 0;
 617 }
 618 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
 619
 620 int rt2x00usb_resume(struct usb_interface *usb_intf)
 621 {
 622         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
 623         struct rt2x00_dev *rt2x00dev = hw->priv;
 624         int retval;
 625
 626         usb_get_dev(interface_to_usbdev(usb_intf));
 627
 628         retval = rt2x00usb_alloc_reg(rt2x00dev);
 629         if (retval)
 630                 return retval;
 631
 632         retval = rt2x00lib_resume(rt2x00dev);
 633         if (retval)
 634                 goto exit_free_reg;
 635
 636         return 0;
 637
 638 exit_free_reg:
 639         rt2x00usb_free_reg(rt2x00dev);
 640
 641         return retval;
 642 }
 643 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
 644 #endif /* CONFIG_PM */
 645
 646 /*
 647  * rt2x00pci module information.
 648  */
 649 MODULE_AUTHOR(DRV_PROJECT);
 650 MODULE_VERSION(DRV_VERSION);
 651 MODULE_DESCRIPTION("rt2x00 library");
 652 MODULE_LICENSE("GPL");