drivers/net/wireless/rt2x00/rt2x00mac.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: rt2x00mac
  23         Abstract: rt2x00 generic mac80211 routines.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28
  29 #include "rt2x00.h"
  30 #include "rt2x00lib.h"
  31
  32 static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
  33                                 struct data_queue *queue,
  34                                 struct sk_buff *frag_skb,
  35                                 struct ieee80211_tx_control *control)
  36 {
  37         struct skb_frame_desc *skbdesc;
  38         struct sk_buff *skb;
  39         int size;
  40
  41         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
  42                 size = sizeof(struct ieee80211_cts);
  43         else
  44                 size = sizeof(struct ieee80211_rts);
  45
  46         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
  47         if (!skb) {
  48                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
  49                 return NETDEV_TX_BUSY;
  50         }
  51
  52         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
  53         skb_put(skb, size);
  54
  55         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
  56                 ieee80211_ctstoself_get(rt2x00dev->hw, control->vif,
  57                                         frag_skb->data, frag_skb->len, control,
  58                                         (struct ieee80211_cts *)(skb->data));
  59         else
  60                 ieee80211_rts_get(rt2x00dev->hw, control->vif,
  61                                   frag_skb->data, frag_skb->len, control,
  62                                   (struct ieee80211_rts *)(skb->data));
  63
  64         /*
  65          * Initialize skb descriptor
  66          */
  67         skbdesc = get_skb_frame_desc(skb);
  68         memset(skbdesc, 0, sizeof(*skbdesc));
  69         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
  70
  71         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
  72                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
  73                 return NETDEV_TX_BUSY;
  74         }
  75
  76         return NETDEV_TX_OK;
  77 }
  78
  79 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
  80                  struct ieee80211_tx_control *control)
  81 {
  82         struct rt2x00_dev *rt2x00dev = hw->priv;
  83         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
  84         struct data_queue *queue;
  85         struct skb_frame_desc *skbdesc;
  86         u16 frame_control;
  87
  88         /*
  89          * Mac80211 might be calling this function while we are trying
  90          * to remove the device or perhaps suspending it.
  91          * Note that we can only stop the TX queues inside the TX path
  92          * due to possible race conditions in mac80211.
  93          */
  94         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
  95                 ieee80211_stop_queues(hw);
  96                 return NETDEV_TX_OK;
  97         }
  98
  99         /*
 100          * Determine which queue to put packet on.
 101          */
 102         if (control->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM &&
 103             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
 104                 queue = rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_ATIM);
 105         else
 106                 queue = rt2x00queue_get_queue(rt2x00dev, control->queue);
 107         if (unlikely(!queue)) {
 108                 ERROR(rt2x00dev,
 109                       "Attempt to send packet over invalid queue %d.\n"
 110                       "Please file bug report to %s.\n",
 111                       control->queue, DRV_PROJECT);
 112                 dev_kfree_skb_any(skb);
 113                 return NETDEV_TX_OK;
 114         }
 115
 116         /*
 117          * If CTS/RTS is required. and this frame is not CTS or RTS,
 118          * create and queue that frame first. But make sure we have
 119          * at least enough entries available to send this CTS/RTS
 120          * frame as well as the data frame.
 121          */
 122         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 123         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
 124             (control->flags & (IEEE80211_TXCTL_USE_RTS_CTS |
 125                                IEEE80211_TXCTL_USE_CTS_PROTECT))) {
 126                 if (rt2x00queue_available(queue) <= 1) {
 127                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 128                         return NETDEV_TX_BUSY;
 129                 }
 130
 131                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb, control)) {
 132                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 133                         return NETDEV_TX_BUSY;
 134                 }
 135         }
 136
 137         /*
 138          * Initialize skb descriptor
 139          */
 140         skbdesc = get_skb_frame_desc(skb);
 141         memset(skbdesc, 0, sizeof(*skbdesc));
 142
 143         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
 144                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 145                 return NETDEV_TX_BUSY;
 146         }
 147
 148         if (rt2x00queue_full(queue))
 149                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 150
 151         if (rt2x00dev->ops->lib->kick_tx_queue)
 152                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, control->queue);
 153
 154         return NETDEV_TX_OK;
 155 }
 156 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
 157
 158 int rt2x00mac_start(struct ieee80211_hw *hw)
 159 {
 160         struct rt2x00_dev *rt2x00dev = hw->priv;
 161
 162         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 163                 return 0;
 164
 165         return rt2x00lib_start(rt2x00dev);
 166 }
 167 EXPORT_SYMBOL_GPL(rt2x00mac_start);
 168
 169 void rt2x00mac_stop(struct ieee80211_hw *hw)
 170 {
 171         struct rt2x00_dev *rt2x00dev = hw->priv;
 172
 173         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 174                 return;
 175
 176         rt2x00lib_stop(rt2x00dev);
 177 }
 178 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
 179
 180 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 181                             struct ieee80211_if_init_conf *conf)
 182 {
 183         struct rt2x00_dev *rt2x00dev = hw->priv;
 184         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 185         struct data_queue *queue =
 186             rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_BEACON);
 187         struct queue_entry *entry = NULL;
 188         unsigned int i;
 189
 190         /*
 191          * Don't allow interfaces to be added
 192          * the device has disappeared.
 193          */
 194         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 195             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
 196                 return -ENODEV;
 197
 198         /*
 199          * When we don't support mixed interfaces (a combination
 200          * of sta and ap virtual interfaces) then we can only
 201          * add this interface when the rival interface count is 0.
 202          */
 203         if (!test_bit(DRIVER_SUPPORT_MIXED_INTERFACES, &rt2x00dev->flags) &&
 204             ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
 205              (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count)))
 206                 return -ENOBUFS;
 207
 208         /*
 209          * Check if we exceeded the maximum amount of supported interfaces.
 210          */
 211         if ((conf->type == IEEE80211_IF_TYPE_AP &&
 212              rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
 213             (conf->type != IEEE80211_IF_TYPE_AP &&
 214              rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
 215                 return -ENOBUFS;
 216
 217         /*
 218          * Loop through all beacon queues to find a free
 219          * entry. Since there are as much beacon entries
 220          * as the maximum interfaces, this search shouldn't
 221          * fail.
 222          */
 223         for (i = 0; i < queue->limit; i++) {
 224                 entry = &queue->entries[i];
 225                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
 226                         break;
 227         }
 228
 229         if (unlikely(i == queue->limit))
 230                 return -ENOBUFS;
 231
 232         /*
 233          * We are now absolutely sure the interface can be created,
 234          * increase interface count and start initialization.
 235          */
 236
 237         if (conf->type == IEEE80211_IF_TYPE_AP)
 238                 rt2x00dev->intf_ap_count++;
 239         else
 240                 rt2x00dev->intf_sta_count++;
 241
 242         spin_lock_init(&intf->lock);
 243         intf->beacon = entry;
 244
 245         if (conf->type == IEEE80211_IF_TYPE_AP)
 246                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
 247         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
 248
 249         /*
 250          * The MAC adddress must be configured after the device
 251          * has been initialized. Otherwise the device can reset
 252          * the MAC registers.
 253          */
 254         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
 255
 256         /*
 257          * Some filters depend on the current working mode. We can force
 258          * an update during the next configure_filter() run by mac80211 by
 259          * resetting the current packet_filter state.
 260          */
 261         rt2x00dev->packet_filter = 0;
 262
 263         return 0;
 264 }
 265 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
 266
 267 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 268                                 struct ieee80211_if_init_conf *conf)
 269 {
 270         struct rt2x00_dev *rt2x00dev = hw->priv;
 271         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 272
 273         /*
 274          * Don't allow interfaces to be remove while
 275          * either the device has disappeared or when
 276          * no interface is present.
 277          */
 278         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 279             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
 280             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
 281                 return;
 282
 283         if (conf->type == IEEE80211_IF_TYPE_AP)
 284                 rt2x00dev->intf_ap_count--;
 285         else
 286                 rt2x00dev->intf_sta_count--;
 287
 288         /*
 289          * Release beacon entry so it is available for
 290          * new interfaces again.
 291          */
 292         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
 293
 294         /*
 295          * Make sure the bssid and mac address registers
 296          * are cleared to prevent false ACKing of frames.
 297          */
 298         rt2x00lib_config_intf(rt2x00dev, intf,
 299                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
 300 }
 301 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 302
 303 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
 304 {
 305         struct rt2x00_dev *rt2x00dev = hw->priv;
 306
 307         /*
 308          * Mac80211 might be calling this function while we are trying
 309          * to remove the device or perhaps suspending it.
 310          */
 311         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 312                 return 0;
 313
 314         /*
 315          * Check if we need to disable the radio,
 316          * if this is not the case, at least the RX must be disabled.
 317          */
 318         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
 319                 if (!conf->radio_enabled)
 320                         rt2x00lib_disable_radio(rt2x00dev);
 321                 else
 322                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 323         }
 324
 325         rt2x00lib_config(rt2x00dev, conf, 0);
 326
 327         /*
 328          * Reenable RX only if the radio should be on.
 329          */
 330         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 331                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 332         else if (conf->radio_enabled)
 333                 return rt2x00lib_enable_radio(rt2x00dev);
 334
 335         return 0;
 336 }
 337 EXPORT_SYMBOL_GPL(rt2x00mac_config);
 338
 339 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 340                                struct ieee80211_vif *vif,
 341                                struct ieee80211_if_conf *conf)
 342 {
 343         struct rt2x00_dev *rt2x00dev = hw->priv;
 344         struct rt2x00_intf *intf = vif_to_intf(vif);
 345         int status;
 346
 347         /*
 348          * Mac80211 might be calling this function while we are trying
 349          * to remove the device or perhaps suspending it.
 350          */
 351         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 352                 return 0;
 353
 354         spin_lock(&intf->lock);
 355
 356         /*
 357          * If the interface does not work in master mode,
 358          * then the bssid value in the interface structure
 359          * should now be set.
 360          */
 361         if (conf->type != IEEE80211_IF_TYPE_AP)
 362                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
 363
 364         spin_unlock(&intf->lock);
 365
 366         /*
 367          * Call rt2x00_config_intf() outside of the spinlock context since
 368          * the call will sleep for USB drivers. By using the ieee80211_if_conf
 369          * values as arguments we make keep access to rt2x00_intf thread safe
 370          * even without the lock.
 371          */
 372         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, conf->bssid);
 373
 374         /*
 375          * We only need to initialize the beacon when master mode is enabled.
 376          */
 377         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
 378                 return 0;
 379
 380         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw,
 381                                                    conf->beacon,
 382                                                    conf->beacon_control);
 383         if (status)
 384                 dev_kfree_skb(conf->beacon);
 385
 386         return status;
 387 }
 388 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
 389
 390 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 391                                 unsigned int changed_flags,
 392                                 unsigned int *total_flags,
 393                                 int mc_count, struct dev_addr_list *mc_list)
 394 {
 395         struct rt2x00_dev *rt2x00dev = hw->priv;
 396
 397         /*
 398          * Mask off any flags we are going to ignore
 399          * from the total_flags field.
 400          */
 401         *total_flags &=
 402             FIF_ALLMULTI |
 403             FIF_FCSFAIL |
 404             FIF_PLCPFAIL |
 405             FIF_CONTROL |
 406             FIF_OTHER_BSS |
 407             FIF_PROMISC_IN_BSS;
 408
 409         /*
 410          * Apply some rules to the filters:
 411          * - Some filters imply different filters to be set.
 412          * - Some things we can't filter out at all.
 413          * - Multicast filter seems to kill broadcast traffic so never use it.
 414          */
 415         *total_flags |= FIF_ALLMULTI;
 416         if (*total_flags & FIF_OTHER_BSS ||
 417             *total_flags & FIF_PROMISC_IN_BSS)
 418                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 419
 420         /*
 421          * Check if there is any work left for us.
 422          */
 423         if (rt2x00dev->packet_filter == *total_flags)
 424                 return;
 425         rt2x00dev->packet_filter = *total_flags;
 426
 427         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 428                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
 429         else
 430                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->filter_work);
 431 }
 432 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
 433
 434 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
 435                         struct ieee80211_low_level_stats *stats)
 436 {
 437         struct rt2x00_dev *rt2x00dev = hw->priv;
 438
 439         /*
 440          * The dot11ACKFailureCount, dot11RTSFailureCount and
 441          * dot11RTSSuccessCount are updated in interrupt time.
 442          * dot11FCSErrorCount is updated in the link tuner.
 443          */
 444         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
 445
 446         return 0;
 447 }
 448 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
 449
 450 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 451                            struct ieee80211_tx_queue_stats *stats)
 452 {
 453         struct rt2x00_dev *rt2x00dev = hw->priv;
 454         unsigned int i;
 455
 456         for (i = 0; i < hw->queues; i++) {
 457                 stats->data[i].len = rt2x00dev->tx[i].length;
 458                 stats->data[i].limit = rt2x00dev->tx[i].limit;
 459                 stats->data[i].count = rt2x00dev->tx[i].count;
 460         }
 461
 462         return 0;
 463 }
 464 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 465
 466 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 467                                 struct ieee80211_vif *vif,
 468                                 struct ieee80211_bss_conf *bss_conf,
 469                                 u32 changes)
 470 {
 471         struct rt2x00_dev *rt2x00dev = hw->priv;
 472         struct rt2x00_intf *intf = vif_to_intf(vif);
 473         unsigned int delayed = 0;
 474
 475         /*
 476          * When the association status has changed we must reset the link
 477          * tuner counter. This is because some drivers determine if they
 478          * should perform link tuning based on the number of seconds
 479          * while associated or not associated.
 480          */
 481         if (changes & BSS_CHANGED_ASSOC) {
 482                 rt2x00dev->link.count = 0;
 483
 484                 if (bss_conf->assoc)
 485                         rt2x00dev->intf_associated++;
 486                 else
 487                         rt2x00dev->intf_associated--;
 488
 489                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 490                         rt2x00leds_led_assoc(rt2x00dev,
 491                                              !!rt2x00dev->intf_associated);
 492                 else
 493                         delayed |= DELAYED_LED_ASSOC;
 494         }
 495
 496         /*
 497          * When the erp information has changed, we should perform
 498          * additional configuration steps. For all other changes we are done.
 499          */
 500         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
 501                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 502                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
 503                 else
 504                         delayed |= DELAYED_CONFIG_ERP;
 505         }
 506
 507         spin_lock(&intf->lock);
 508         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
 509         if (delayed) {
 510                 intf->delayed_flags |= delayed;
 511                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->intf_work);
 512         }
 513         spin_unlock(&intf->lock);
 514 }
 515 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
 516
 517 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, int queue_idx,
 518                       const struct ieee80211_tx_queue_params *params)
 519 {
 520         struct rt2x00_dev *rt2x00dev = hw->priv;
 521         struct data_queue *queue;
 522
 523         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
 524         if (unlikely(!queue))
 525                 return -EINVAL;
 526
 527         /*
 528          * The passed variables are stored as real value ((2^n)-1).
 529          * Ralink registers require to know the bit number 'n'.
 530          */
 531         if (params->cw_min > 0)
 532                 queue->cw_min = fls(params->cw_min);
 533         else
 534                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
 535
 536         if (params->cw_max > 0)
 537                 queue->cw_max = fls(params->cw_max);
 538         else
 539                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
 540
 541         if (params->aifs >= 0)
 542                 queue->aifs = params->aifs;
 543         else
 544                 queue->aifs = 2;
 545
 546         INFO(rt2x00dev,
 547              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
 548              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
 549
 550         return 0;
 551 }
 552 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);