net/mac80211/ht.c

   1 /*
   2  * HT handling
   3  *
   4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Copyright 2002-2005, Instant802 Networks, Inc.
   6  * Copyright 2005-2006, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9  * Copyright 2007-2010, Intel Corporation
  10  * Copyright 2017       Intel Deutschland GmbH
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/ieee80211.h>
  18 #include <linux/export.h>
  19 #include <net/mac80211.h>
  20 #include "ieee80211_i.h"
  21 #include "rate.h"
  22
  23 static void __check_htcap_disable(struct ieee80211_ht_cap *ht_capa,
  24                                   struct ieee80211_ht_cap *ht_capa_mask,
  25                                   struct ieee80211_sta_ht_cap *ht_cap,
  26                                   u16 flag)
  27 {
  28         __le16 le_flag = cpu_to_le16(flag);
  29         if (ht_capa_mask->cap_info & le_flag) {
  30                 if (!(ht_capa->cap_info & le_flag))
  31                         ht_cap->cap &= ~flag;
  32         }
  33 }
  34
  35 static void __check_htcap_enable(struct ieee80211_ht_cap *ht_capa,
  36                                   struct ieee80211_ht_cap *ht_capa_mask,
  37                                   struct ieee80211_sta_ht_cap *ht_cap,
  38                                   u16 flag)
  39 {
  40         __le16 le_flag = cpu_to_le16(flag);
  41
  42         if ((ht_capa_mask->cap_info & le_flag) &&
  43             (ht_capa->cap_info & le_flag))
  44                 ht_cap->cap |= flag;
  45 }
  46
  47 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
  48                                      struct ieee80211_sta_ht_cap *ht_cap)
  49 {
  50         struct ieee80211_ht_cap *ht_capa, *ht_capa_mask;
  51         u8 *scaps, *smask;
  52         int i;
  53
  54         if (!ht_cap->ht_supported)
  55                 return;
  56
  57         switch (sdata->vif.type) {
  58         case NL80211_IFTYPE_STATION:
  59                 ht_capa = &sdata->u.mgd.ht_capa;
  60                 ht_capa_mask = &sdata->u.mgd.ht_capa_mask;
  61                 break;
  62         case NL80211_IFTYPE_ADHOC:
  63                 ht_capa = &sdata->u.ibss.ht_capa;
  64                 ht_capa_mask = &sdata->u.ibss.ht_capa_mask;
  65                 break;
  66         default:
  67                 WARN_ON_ONCE(1);
  68                 return;
  69         }
  70
  71         scaps = (u8 *)(&ht_capa->mcs.rx_mask);
  72         smask = (u8 *)(&ht_capa_mask->mcs.rx_mask);
  73
  74         /* NOTE:  If you add more over-rides here, update register_hw
  75          * ht_capa_mod_mask logic in main.c as well.
  76          * And, if this method can ever change ht_cap.ht_supported, fix
  77          * the check in ieee80211_add_ht_ie.
  78          */
  79
  80         /* check for HT over-rides, MCS rates first. */
  81         for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
  82                 u8 m = smask[i];
  83                 ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
  84                 /* Add back rates that are supported */
  85                 ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
  86         }
  87
  88         /* Force removal of HT-40 capabilities? */
  89         __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  90                               IEEE80211_HT_CAP_SUP_WIDTH_20_40);
  91         __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  92                               IEEE80211_HT_CAP_SGI_40);
  93
  94         /* Allow user to disable SGI-20 (SGI-40 is handled above) */
  95         __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
  96                               IEEE80211_HT_CAP_SGI_20);
  97
  98         /* Allow user to disable the max-AMSDU bit. */
  99         __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
 100                               IEEE80211_HT_CAP_MAX_AMSDU);
 101
 102         /* Allow user to disable LDPC */
 103         __check_htcap_disable(ht_capa, ht_capa_mask, ht_cap,
 104                               IEEE80211_HT_CAP_LDPC_CODING);
 105
 106         /* Allow user to enable 40 MHz intolerant bit. */
 107         __check_htcap_enable(ht_capa, ht_capa_mask, ht_cap,
 108                              IEEE80211_HT_CAP_40MHZ_INTOLERANT);
 109
 110         /* Allow user to decrease AMPDU factor */
 111         if (ht_capa_mask->ampdu_params_info &
 112             IEEE80211_HT_AMPDU_PARM_FACTOR) {
 113                 u8 n = ht_capa->ampdu_params_info &
 114                        IEEE80211_HT_AMPDU_PARM_FACTOR;
 115                 if (n < ht_cap->ampdu_factor)
 116                         ht_cap->ampdu_factor = n;
 117         }
 118
 119         /* Allow the user to increase AMPDU density. */
 120         if (ht_capa_mask->ampdu_params_info &
 121             IEEE80211_HT_AMPDU_PARM_DENSITY) {
 122                 u8 n = (ht_capa->ampdu_params_info &
 123                         IEEE80211_HT_AMPDU_PARM_DENSITY)
 124                         >> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
 125                 if (n > ht_cap->ampdu_density)
 126                         ht_cap->ampdu_density = n;
 127         }
 128 }
 129
 130
 131 bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
 132                                        struct ieee80211_supported_band *sband,
 133                                        const struct ieee80211_ht_cap *ht_cap_ie,
 134                                        struct sta_info *sta)
 135 {
 136         struct ieee80211_sta_ht_cap ht_cap, own_cap;
 137         u8 ampdu_info, tx_mcs_set_cap;
 138         int i, max_tx_streams;
 139         bool changed;
 140         enum ieee80211_sta_rx_bandwidth bw;
 141         enum ieee80211_smps_mode smps_mode;
 142
 143         memset(&ht_cap, 0, sizeof(ht_cap));
 144
 145         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
 146                 goto apply;
 147
 148         ht_cap.ht_supported = true;
 149
 150         own_cap = sband->ht_cap;
 151
 152         /*
 153          * If user has specified capability over-rides, take care
 154          * of that if the station we're setting up is the AP or TDLS peer that
 155          * we advertised a restricted capability set to. Override
 156          * our own capabilities and then use those below.
 157          */
 158         if (sdata->vif.type == NL80211_IFTYPE_STATION ||
 159             sdata->vif.type == NL80211_IFTYPE_ADHOC)
 160                 ieee80211_apply_htcap_overrides(sdata, &own_cap);
 161
 162         /*
 163          * The bits listed in this expression should be
 164          * the same for the peer and us, if the station
 165          * advertises more then we can't use those thus
 166          * we mask them out.
 167          */
 168         ht_cap.cap = le16_to_cpu(ht_cap_ie->cap_info) &
 169                 (own_cap.cap | ~(IEEE80211_HT_CAP_LDPC_CODING |
 170                                  IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
 171                                  IEEE80211_HT_CAP_GRN_FLD |
 172                                  IEEE80211_HT_CAP_SGI_20 |
 173                                  IEEE80211_HT_CAP_SGI_40 |
 174                                  IEEE80211_HT_CAP_DSSSCCK40));
 175
 176         /*
 177          * The STBC bits are asymmetric -- if we don't have
 178          * TX then mask out the peer's RX and vice versa.
 179          */
 180         if (!(own_cap.cap & IEEE80211_HT_CAP_TX_STBC))
 181                 ht_cap.cap &= ~IEEE80211_HT_CAP_RX_STBC;
 182         if (!(own_cap.cap & IEEE80211_HT_CAP_RX_STBC))
 183                 ht_cap.cap &= ~IEEE80211_HT_CAP_TX_STBC;
 184
 185         ampdu_info = ht_cap_ie->ampdu_params_info;
 186         ht_cap.ampdu_factor =
 187                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
 188         ht_cap.ampdu_density =
 189                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
 190
 191         /* own MCS TX capabilities */
 192         tx_mcs_set_cap = own_cap.mcs.tx_params;
 193
 194         /* Copy peer MCS TX capabilities, the driver might need them. */
 195         ht_cap.mcs.tx_params = ht_cap_ie->mcs.tx_params;
 196
 197         /* can we TX with MCS rates? */
 198         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
 199                 goto apply;
 200
 201         /* Counting from 0, therefore +1 */
 202         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
 203                 max_tx_streams =
 204                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
 205                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
 206         else
 207                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
 208
 209         /*
 210          * 802.11n-2009 20.3.5 / 20.6 says:
 211          * - indices 0 to 7 and 32 are single spatial stream
 212          * - 8 to 31 are multiple spatial streams using equal modulation
 213          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
 214          * - remainder are multiple spatial streams using unequal modulation
 215          */
 216         for (i = 0; i < max_tx_streams; i++)
 217                 ht_cap.mcs.rx_mask[i] =
 218                         own_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
 219
 220         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
 221                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
 222                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
 223                         ht_cap.mcs.rx_mask[i] =
 224                                 own_cap.mcs.rx_mask[i] &
 225                                         ht_cap_ie->mcs.rx_mask[i];
 226
 227         /* handle MCS rate 32 too */
 228         if (own_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 229                 ht_cap.mcs.rx_mask[32/8] |= 1;
 230
 231         /* set Rx highest rate */
 232         ht_cap.mcs.rx_highest = ht_cap_ie->mcs.rx_highest;
 233
 234         if (ht_cap.cap & IEEE80211_HT_CAP_MAX_AMSDU)
 235                 sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_7935;
 236         else
 237                 sta->sta.max_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_3839;
 238
 239  apply:
 240         changed = memcmp(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
 241
 242         memcpy(&sta->sta.ht_cap, &ht_cap, sizeof(ht_cap));
 243
 244         switch (sdata->vif.bss_conf.chandef.width) {
 245         default:
 246                 WARN_ON_ONCE(1);
 247                 /* fall through */
 248         case NL80211_CHAN_WIDTH_20_NOHT:
 249         case NL80211_CHAN_WIDTH_20:
 250                 bw = IEEE80211_STA_RX_BW_20;
 251                 break;
 252         case NL80211_CHAN_WIDTH_40:
 253         case NL80211_CHAN_WIDTH_80:
 254         case NL80211_CHAN_WIDTH_80P80:
 255         case NL80211_CHAN_WIDTH_160:
 256                 bw = ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 257                                 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
 258                 break;
 259         }
 260
 261         sta->sta.bandwidth = bw;
 262
 263         sta->cur_max_bandwidth =
 264                 ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
 265                                 IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
 266
 267         switch ((ht_cap.cap & IEEE80211_HT_CAP_SM_PS)
 268                         >> IEEE80211_HT_CAP_SM_PS_SHIFT) {
 269         case WLAN_HT_CAP_SM_PS_INVALID:
 270         case WLAN_HT_CAP_SM_PS_STATIC:
 271                 smps_mode = IEEE80211_SMPS_STATIC;
 272                 break;
 273         case WLAN_HT_CAP_SM_PS_DYNAMIC:
 274                 smps_mode = IEEE80211_SMPS_DYNAMIC;
 275                 break;
 276         case WLAN_HT_CAP_SM_PS_DISABLED:
 277                 smps_mode = IEEE80211_SMPS_OFF;
 278                 break;
 279         }
 280
 281         if (smps_mode != sta->sta.smps_mode)
 282                 changed = true;
 283         sta->sta.smps_mode = smps_mode;
 284
 285         return changed;
 286 }
 287
 288 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta,
 289                                          enum ieee80211_agg_stop_reason reason)
 290 {
 291         int i;
 292
 293         for (i = 0; i <  IEEE80211_NUM_TIDS; i++) {
 294                 __ieee80211_stop_tx_ba_session(sta, i, reason);
 295                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 296                                                WLAN_REASON_QSTA_LEAVE_QBSS,
 297                                                reason != AGG_STOP_DESTROY_STA &&
 298                                                reason != AGG_STOP_PEER_REQUEST);
 299         }
 300
 301         /* stopping might queue the work again - so cancel only afterwards */
 302         cancel_work_sync(&sta->ampdu_mlme.work);
 303 }
 304
 305 void ieee80211_ba_session_work(struct work_struct *work)
 306 {
 307         struct sta_info *sta =
 308                 container_of(work, struct sta_info, ampdu_mlme.work);
 309         struct tid_ampdu_tx *tid_tx;
 310         int tid;
 311
 312         /*
 313          * When this flag is set, new sessions should be
 314          * blocked, and existing sessions will be torn
 315          * down by the code that set the flag, so this
 316          * need not run.
 317          */
 318         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
 319                 return;
 320
 321         mutex_lock(&sta->ampdu_mlme.mtx);
 322         for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
 323                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 324                         ___ieee80211_stop_rx_ba_session(
 325                                 sta, tid, WLAN_BACK_RECIPIENT,
 326                                 WLAN_REASON_QSTA_TIMEOUT, true);
 327
 328                 if (test_and_clear_bit(tid,
 329                                        sta->ampdu_mlme.tid_rx_stop_requested))
 330                         ___ieee80211_stop_rx_ba_session(
 331                                 sta, tid, WLAN_BACK_RECIPIENT,
 332                                 WLAN_REASON_UNSPECIFIED, true);
 333
 334                 if (test_and_clear_bit(tid,
 335                                        sta->ampdu_mlme.tid_rx_manage_offl))
 336                         __ieee80211_start_rx_ba_session(sta, 0, 0, 0, 1, tid,
 337                                                         IEEE80211_MAX_AMPDU_BUF,
 338                                                         false, true);
 339
 340                 if (test_and_clear_bit(tid + IEEE80211_NUM_TIDS,
 341                                        sta->ampdu_mlme.tid_rx_manage_offl))
 342                         ___ieee80211_stop_rx_ba_session(
 343                                 sta, tid, WLAN_BACK_RECIPIENT,
 344                                 0, false);
 345
 346                 spin_lock_bh(&sta->lock);
 347
 348                 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 349                 if (tid_tx) {
 350                         /*
 351                          * Assign it over to the normal tid_tx array
 352                          * where it "goes live".
 353                          */
 354
 355                         sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 356                         /* could there be a race? */
 357                         if (sta->ampdu_mlme.tid_tx[tid])
 358                                 kfree(tid_tx);
 359                         else
 360                                 ieee80211_assign_tid_tx(sta, tid, tid_tx);
 361                         spin_unlock_bh(&sta->lock);
 362
 363                         ieee80211_tx_ba_session_handle_start(sta, tid);
 364                         continue;
 365                 }
 366                 spin_unlock_bh(&sta->lock);
 367
 368                 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 369                 if (!tid_tx)
 370                         continue;
 371
 372                 if (test_and_clear_bit(HT_AGG_STATE_START_CB, &tid_tx->state))
 373                         ieee80211_start_tx_ba_cb(sta, tid, tid_tx);
 374                 if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
 375                         ___ieee80211_stop_tx_ba_session(sta, tid,
 376                                                         AGG_STOP_LOCAL_REQUEST);
 377                 if (test_and_clear_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state))
 378                         ieee80211_stop_tx_ba_cb(sta, tid, tid_tx);
 379         }
 380         mutex_unlock(&sta->ampdu_mlme.mtx);
 381 }
 382
 383 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 384                           const u8 *da, u16 tid,
 385                           u16 initiator, u16 reason_code)
 386 {
 387         struct ieee80211_local *local = sdata->local;
 388         struct sk_buff *skb;
 389         struct ieee80211_mgmt *mgmt;
 390         u16 params;
 391
 392         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 393         if (!skb)
 394                 return;
 395
 396         skb_reserve(skb, local->hw.extra_tx_headroom);
 397         mgmt = skb_put_zero(skb, 24);
 398         memcpy(mgmt->da, da, ETH_ALEN);
 399         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 400         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 401             sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
 402             sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 403                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 404         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 405                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 406         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
 407                 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
 408
 409         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 410                                           IEEE80211_STYPE_ACTION);
 411
 412         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 413
 414         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 415         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 416         params = (u16)(initiator << 11);        /* bit 11 initiator */
 417         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 418
 419         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 420         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 421
 422         ieee80211_tx_skb(sdata, skb);
 423 }
 424
 425 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 426                              struct sta_info *sta,
 427                              struct ieee80211_mgmt *mgmt, size_t len)
 428 {
 429         u16 tid, params;
 430         u16 initiator;
 431
 432         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 433         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 434         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 435
 436         ht_dbg_ratelimited(sdata, "delba from %pM (%s) tid %d reason code %d\n",
 437                            mgmt->sa, initiator ? "initiator" : "recipient",
 438                            tid,
 439                            le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 440
 441         if (initiator == WLAN_BACK_INITIATOR)
 442                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 443                                                true);
 444         else
 445                 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_PEER_REQUEST);
 446 }
 447
 448 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 449                                enum ieee80211_smps_mode smps, const u8 *da,
 450                                const u8 *bssid)
 451 {
 452         struct ieee80211_local *local = sdata->local;
 453         struct sk_buff *skb;
 454         struct ieee80211_mgmt *action_frame;
 455
 456         /* 27 = header + category + action + smps mode */
 457         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 458         if (!skb)
 459                 return -ENOMEM;
 460
 461         skb_reserve(skb, local->hw.extra_tx_headroom);
 462         action_frame = skb_put(skb, 27);
 463         memcpy(action_frame->da, da, ETH_ALEN);
 464         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 465         memcpy(action_frame->bssid, bssid, ETH_ALEN);
 466         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 467                                                   IEEE80211_STYPE_ACTION);
 468         action_frame->u.action.category = WLAN_CATEGORY_HT;
 469         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 470         switch (smps) {
 471         case IEEE80211_SMPS_AUTOMATIC:
 472         case IEEE80211_SMPS_NUM_MODES:
 473                 WARN_ON(1);
 474         case IEEE80211_SMPS_OFF:
 475                 action_frame->u.action.u.ht_smps.smps_control =
 476                                 WLAN_HT_SMPS_CONTROL_DISABLED;
 477                 break;
 478         case IEEE80211_SMPS_STATIC:
 479                 action_frame->u.action.u.ht_smps.smps_control =
 480                                 WLAN_HT_SMPS_CONTROL_STATIC;
 481                 break;
 482         case IEEE80211_SMPS_DYNAMIC:
 483                 action_frame->u.action.u.ht_smps.smps_control =
 484                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
 485                 break;
 486         }
 487
 488         /* we'll do more on status of this frame */
 489         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 490         ieee80211_tx_skb(sdata, skb);
 491
 492         return 0;
 493 }
 494
 495 void ieee80211_request_smps_mgd_work(struct work_struct *work)
 496 {
 497         struct ieee80211_sub_if_data *sdata =
 498                 container_of(work, struct ieee80211_sub_if_data,
 499                              u.mgd.request_smps_work);
 500
 501         sdata_lock(sdata);
 502         __ieee80211_request_smps_mgd(sdata, sdata->u.mgd.driver_smps_mode);
 503         sdata_unlock(sdata);
 504 }
 505
 506 void ieee80211_request_smps_ap_work(struct work_struct *work)
 507 {
 508         struct ieee80211_sub_if_data *sdata =
 509                 container_of(work, struct ieee80211_sub_if_data,
 510                              u.ap.request_smps_work);
 511
 512         sdata_lock(sdata);
 513         if (sdata_dereference(sdata->u.ap.beacon, sdata))
 514                 __ieee80211_request_smps_ap(sdata,
 515                                             sdata->u.ap.driver_smps_mode);
 516         sdata_unlock(sdata);
 517 }
 518
 519 void ieee80211_request_smps(struct ieee80211_vif *vif,
 520                             enum ieee80211_smps_mode smps_mode)
 521 {
 522         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 523
 524         if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION &&
 525                          vif->type != NL80211_IFTYPE_AP))
 526                 return;
 527
 528         if (vif->type == NL80211_IFTYPE_STATION) {
 529                 if (sdata->u.mgd.driver_smps_mode == smps_mode)
 530                         return;
 531                 sdata->u.mgd.driver_smps_mode = smps_mode;
 532                 ieee80211_queue_work(&sdata->local->hw,
 533                                      &sdata->u.mgd.request_smps_work);
 534         } else {
 535                 /* AUTOMATIC is meaningless in AP mode */
 536                 if (WARN_ON_ONCE(smps_mode == IEEE80211_SMPS_AUTOMATIC))
 537                         return;
 538                 if (sdata->u.ap.driver_smps_mode == smps_mode)
 539                         return;
 540                 sdata->u.ap.driver_smps_mode = smps_mode;
 541                 ieee80211_queue_work(&sdata->local->hw,
 542                                      &sdata->u.ap.request_smps_work);
 543         }
 544 }
 545 /* this might change ... don't want non-open drivers using it */
 546 EXPORT_SYMBOL_GPL(ieee80211_request_smps);