drivers/net/wireless/rt2x00/rt2x00mac.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: 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_ring *ring,
  34                                 struct sk_buff *frag_skb,
  35                                 struct ieee80211_tx_control *control)
  36 {
  37         struct sk_buff *skb;
  38         int size;
  39
  40         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
  41                 size = sizeof(struct ieee80211_cts);
  42         else
  43                 size = sizeof(struct ieee80211_rts);
  44
  45         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
  46         if (!skb) {
  47                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
  48                 return NETDEV_TX_BUSY;
  49         }
  50
  51         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
  52         skb_put(skb, size);
  53
  54         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
  55                 ieee80211_ctstoself_get(rt2x00dev->hw, rt2x00dev->interface.id,
  56                                         frag_skb->data, frag_skb->len, control,
  57                                         (struct ieee80211_cts *)(skb->data));
  58         else
  59                 ieee80211_rts_get(rt2x00dev->hw, rt2x00dev->interface.id,
  60                                   frag_skb->data, frag_skb->len, control,
  61                                   (struct ieee80211_rts *)(skb->data));
  62
  63         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, ring, skb, control)) {
  64                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
  65                 return NETDEV_TX_BUSY;
  66         }
  67
  68         return NETDEV_TX_OK;
  69 }
  70
  71 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
  72                  struct ieee80211_tx_control *control)
  73 {
  74         struct rt2x00_dev *rt2x00dev = hw->priv;
  75         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
  76         struct data_ring *ring;
  77         u16 frame_control;
  78
  79         /*
  80          * Mac80211 might be calling this function while we are trying
  81          * to remove the device or perhaps suspending it.
  82          * Note that we can only stop the TX queues inside the TX path
  83          * due to possible race conditions in mac80211.
  84          */
  85         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
  86                 ieee80211_stop_queues(hw);
  87                 return NETDEV_TX_OK;
  88         }
  89
  90         /*
  91          * Determine which ring to put packet on.
  92          */
  93         ring = rt2x00lib_get_ring(rt2x00dev, control->queue);
  94         if (unlikely(!ring)) {
  95                 ERROR(rt2x00dev,
  96                       "Attempt to send packet over invalid queue %d.\n"
  97                       "Please file bug report to %s.\n",
  98                       control->queue, DRV_PROJECT);
  99                 dev_kfree_skb_any(skb);
 100                 return NETDEV_TX_OK;
 101         }
 102
 103         /*
 104          * If CTS/RTS is required. and this frame is not CTS or RTS,
 105          * create and queue that frame first. But make sure we have
 106          * at least enough entries available to send this CTS/RTS
 107          * frame as well as the data frame.
 108          */
 109         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 110         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
 111             (control->flags & (IEEE80211_TXCTL_USE_RTS_CTS |
 112                                IEEE80211_TXCTL_USE_CTS_PROTECT))) {
 113                 if (rt2x00_ring_free(ring) <= 1) {
 114                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 115                         return NETDEV_TX_BUSY;
 116                 }
 117
 118                 if (rt2x00mac_tx_rts_cts(rt2x00dev, ring, skb, control)) {
 119                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 120                         return NETDEV_TX_BUSY;
 121                 }
 122         }
 123
 124         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, ring, skb, control)) {
 125                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 126                 return NETDEV_TX_BUSY;
 127         }
 128
 129         if (rt2x00_ring_full(ring))
 130                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 131
 132         if (rt2x00dev->ops->lib->kick_tx_queue)
 133                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, control->queue);
 134
 135         return NETDEV_TX_OK;
 136 }
 137 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
 138
 139 int rt2x00mac_start(struct ieee80211_hw *hw)
 140 {
 141         struct rt2x00_dev *rt2x00dev = hw->priv;
 142
 143         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 144                 return 0;
 145
 146         return rt2x00lib_start(rt2x00dev);
 147 }
 148 EXPORT_SYMBOL_GPL(rt2x00mac_start);
 149
 150 void rt2x00mac_stop(struct ieee80211_hw *hw)
 151 {
 152         struct rt2x00_dev *rt2x00dev = hw->priv;
 153
 154         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 155                 return;
 156
 157         rt2x00lib_stop(rt2x00dev);
 158 }
 159 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
 160
 161 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 162                             struct ieee80211_if_init_conf *conf)
 163 {
 164         struct rt2x00_dev *rt2x00dev = hw->priv;
 165         struct interface *intf = &rt2x00dev->interface;
 166
 167         /* FIXME: Beaconing is broken in rt2x00. */
 168         if (conf->type == IEEE80211_IF_TYPE_IBSS ||
 169             conf->type == IEEE80211_IF_TYPE_AP) {
 170                 ERROR(rt2x00dev,
 171                       "rt2x00 does not support Adhoc or Master mode");
 172                 return -EOPNOTSUPP;
 173         }
 174
 175         /*
 176          * Don't allow interfaces to be added while
 177          * either the device has disappeared or when
 178          * another interface is already present.
 179          */
 180         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 181             is_interface_present(intf))
 182                 return -ENOBUFS;
 183
 184         intf->id = conf->vif;
 185         intf->type = conf->type;
 186         if (conf->type == IEEE80211_IF_TYPE_AP)
 187                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
 188         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
 189
 190         /*
 191          * The MAC adddress must be configured after the device
 192          * has been initialized. Otherwise the device can reset
 193          * the MAC registers.
 194          */
 195         rt2x00lib_config_mac_addr(rt2x00dev, intf->mac);
 196         rt2x00lib_config_type(rt2x00dev, conf->type);
 197
 198         return 0;
 199 }
 200 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
 201
 202 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 203                                 struct ieee80211_if_init_conf *conf)
 204 {
 205         struct rt2x00_dev *rt2x00dev = hw->priv;
 206         struct interface *intf = &rt2x00dev->interface;
 207
 208         /*
 209          * Don't allow interfaces to be remove while
 210          * either the device has disappeared or when
 211          * no interface is present.
 212          */
 213         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 214             !is_interface_present(intf))
 215                 return;
 216
 217         intf->id = 0;
 218         intf->type = IEEE80211_IF_TYPE_INVALID;
 219         memset(&intf->bssid, 0x00, ETH_ALEN);
 220         memset(&intf->mac, 0x00, ETH_ALEN);
 221
 222         /*
 223          * Make sure the bssid and mac address registers
 224          * are cleared to prevent false ACKing of frames.
 225          */
 226         rt2x00lib_config_mac_addr(rt2x00dev, intf->mac);
 227         rt2x00lib_config_bssid(rt2x00dev, intf->bssid);
 228         rt2x00lib_config_type(rt2x00dev, intf->type);
 229 }
 230 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 231
 232 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
 233 {
 234         struct rt2x00_dev *rt2x00dev = hw->priv;
 235
 236         /*
 237          * Mac80211 might be calling this function while we are trying
 238          * to remove the device or perhaps suspending it.
 239          */
 240         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 241                 return 0;
 242
 243         /*
 244          * Check if we need to disable the radio,
 245          * if this is not the case, at least the RX must be disabled.
 246          */
 247         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
 248                 if (!conf->radio_enabled)
 249                         rt2x00lib_disable_radio(rt2x00dev);
 250                 else
 251                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 252         }
 253
 254         rt2x00lib_config(rt2x00dev, conf, 0);
 255
 256         /*
 257          * Reenable RX only if the radio should be on.
 258          */
 259         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 260                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 261         else if (conf->radio_enabled)
 262                 return rt2x00lib_enable_radio(rt2x00dev);
 263
 264         return 0;
 265 }
 266 EXPORT_SYMBOL_GPL(rt2x00mac_config);
 267
 268 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 269                                struct ieee80211_vif *vif,
 270                                struct ieee80211_if_conf *conf)
 271 {
 272         struct rt2x00_dev *rt2x00dev = hw->priv;
 273         struct interface *intf = &rt2x00dev->interface;
 274         int status;
 275
 276         /*
 277          * Mac80211 might be calling this function while we are trying
 278          * to remove the device or perhaps suspending it.
 279          */
 280         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 281                 return 0;
 282
 283         /*
 284          * If the given type does not match the configured type,
 285          * there has been a problem.
 286          */
 287         if (conf->type != intf->type)
 288                 return -EINVAL;
 289
 290         /*
 291          * If the interface does not work in master mode,
 292          * then the bssid value in the interface structure
 293          * should now be set.
 294          */
 295         if (conf->type != IEEE80211_IF_TYPE_AP)
 296                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
 297         rt2x00lib_config_bssid(rt2x00dev, intf->bssid);
 298
 299         /*
 300          * We only need to initialize the beacon when master mode is enabled.
 301          */
 302         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
 303                 return 0;
 304
 305         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw,
 306                                                    conf->beacon,
 307                                                    conf->beacon_control);
 308         if (status)
 309                 dev_kfree_skb(conf->beacon);
 310
 311         return status;
 312 }
 313 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
 314
 315 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
 316                         struct ieee80211_low_level_stats *stats)
 317 {
 318         struct rt2x00_dev *rt2x00dev = hw->priv;
 319
 320         /*
 321          * The dot11ACKFailureCount, dot11RTSFailureCount and
 322          * dot11RTSSuccessCount are updated in interrupt time.
 323          * dot11FCSErrorCount is updated in the link tuner.
 324          */
 325         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
 326
 327         return 0;
 328 }
 329 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
 330
 331 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 332                            struct ieee80211_tx_queue_stats *stats)
 333 {
 334         struct rt2x00_dev *rt2x00dev = hw->priv;
 335         unsigned int i;
 336
 337         for (i = 0; i < hw->queues; i++)
 338                 memcpy(&stats->data[i], &rt2x00dev->tx[i].stats,
 339                        sizeof(rt2x00dev->tx[i].stats));
 340
 341         return 0;
 342 }
 343 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 344
 345 void rt2x00mac_erp_ie_changed(struct ieee80211_hw *hw, u8 changes,
 346                               int cts_protection, int preamble)
 347 {
 348         struct rt2x00_dev *rt2x00dev = hw->priv;
 349         int short_preamble;
 350         int ack_timeout;
 351         int ack_consume_time;
 352         int difs;
 353
 354         /*
 355          * We only support changing preamble mode.
 356          */
 357         if (!(changes & IEEE80211_ERP_CHANGE_PREAMBLE))
 358                 return;
 359
 360         short_preamble = !preamble;
 361         preamble = !!(preamble) ? PREAMBLE : SHORT_PREAMBLE;
 362
 363         difs = (hw->conf.flags & IEEE80211_CONF_SHORT_SLOT_TIME) ?
 364                 SHORT_DIFS : DIFS;
 365         ack_timeout = difs + PLCP + preamble + get_duration(ACK_SIZE, 10);
 366
 367         ack_consume_time = SIFS + PLCP + preamble + get_duration(ACK_SIZE, 10);
 368
 369         if (short_preamble)
 370                 __set_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
 371         else
 372                 __clear_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
 373
 374         rt2x00dev->ops->lib->config_preamble(rt2x00dev, short_preamble,
 375                                              ack_timeout, ack_consume_time);
 376 }
 377 EXPORT_SYMBOL_GPL(rt2x00mac_erp_ie_changed);
 378
 379 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, int queue,
 380                       const struct ieee80211_tx_queue_params *params)
 381 {
 382         struct rt2x00_dev *rt2x00dev = hw->priv;
 383         struct data_ring *ring;
 384
 385         ring = rt2x00lib_get_ring(rt2x00dev, queue);
 386         if (unlikely(!ring))
 387                 return -EINVAL;
 388
 389         /*
 390          * The passed variables are stored as real value ((2^n)-1).
 391          * Ralink registers require to know the bit number 'n'.
 392          */
 393         if (params->cw_min)
 394                 ring->tx_params.cw_min = fls(params->cw_min);
 395         else
 396                 ring->tx_params.cw_min = 5; /* cw_min: 2^5 = 32. */
 397
 398         if (params->cw_max)
 399                 ring->tx_params.cw_max = fls(params->cw_max);
 400         else
 401                 ring->tx_params.cw_max = 10; /* cw_min: 2^10 = 1024. */
 402
 403         if (params->aifs)
 404                 ring->tx_params.aifs = params->aifs;
 405         else
 406                 ring->tx_params.aifs = 2;
 407
 408         INFO(rt2x00dev,
 409              "Configured TX ring %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
 410              queue, ring->tx_params.cw_min, ring->tx_params.cw_max,
 411              ring->tx_params.aifs);
 412
 413         return 0;
 414 }
 415 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);