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  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/ieee80211.h>
  17 #include <linux/export.h>
  18 #include <net/mac80211.h>
  19 #include "ieee80211_i.h"
  20 #include "rate.h"
  21
  22 void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
  23                                        struct ieee80211_ht_cap *ht_cap_ie,
  24                                        struct ieee80211_sta_ht_cap *ht_cap)
  25 {
  26         u8 ampdu_info, tx_mcs_set_cap;
  27         int i, max_tx_streams;
  28
  29         BUG_ON(!ht_cap);
  30
  31         memset(ht_cap, 0, sizeof(*ht_cap));
  32
  33         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
  34                 return;
  35
  36         ht_cap->ht_supported = true;
  37
  38         /*
  39          * The bits listed in this expression should be
  40          * the same for the peer and us, if the station
  41          * advertises more then we can't use those thus
  42          * we mask them out.
  43          */
  44         ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) &
  45                 (sband->ht_cap.cap |
  46                  ~(IEEE80211_HT_CAP_LDPC_CODING |
  47                    IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
  48                    IEEE80211_HT_CAP_GRN_FLD |
  49                    IEEE80211_HT_CAP_SGI_20 |
  50                    IEEE80211_HT_CAP_SGI_40 |
  51                    IEEE80211_HT_CAP_DSSSCCK40));
  52         /*
  53          * The STBC bits are asymmetric -- if we don't have
  54          * TX then mask out the peer's RX and vice versa.
  55          */
  56         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_TX_STBC))
  57                 ht_cap->cap &= ~IEEE80211_HT_CAP_RX_STBC;
  58         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_RX_STBC))
  59                 ht_cap->cap &= ~IEEE80211_HT_CAP_TX_STBC;
  60
  61         ampdu_info = ht_cap_ie->ampdu_params_info;
  62         ht_cap->ampdu_factor =
  63                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
  64         ht_cap->ampdu_density =
  65                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
  66
  67         /* own MCS TX capabilities */
  68         tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;
  69
  70         /* Copy peer MCS TX capabilities, the driver might need them. */
  71         ht_cap->mcs.tx_params = ht_cap_ie->mcs.tx_params;
  72
  73         /* can we TX with MCS rates? */
  74         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
  75                 return;
  76
  77         /* Counting from 0, therefore +1 */
  78         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
  79                 max_tx_streams =
  80                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
  81                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
  82         else
  83                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
  84
  85         /*
  86          * 802.11n-2009 20.3.5 / 20.6 says:
  87          * - indices 0 to 7 and 32 are single spatial stream
  88          * - 8 to 31 are multiple spatial streams using equal modulation
  89          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
  90          * - remainder are multiple spatial streams using unequal modulation
  91          */
  92         for (i = 0; i < max_tx_streams; i++)
  93                 ht_cap->mcs.rx_mask[i] =
  94                         sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
  95
  96         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
  97                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
  98                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
  99                         ht_cap->mcs.rx_mask[i] =
 100                                 sband->ht_cap.mcs.rx_mask[i] &
 101                                         ht_cap_ie->mcs.rx_mask[i];
 102
 103         /* handle MCS rate 32 too */
 104         if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 105                 ht_cap->mcs.rx_mask[32/8] |= 1;
 106 }
 107
 108 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
 109 {
 110         int i;
 111
 112         cancel_work_sync(&sta->ampdu_mlme.work);
 113
 114         for (i = 0; i <  STA_TID_NUM; i++) {
 115                 __ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR, tx);
 116                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 117                                                WLAN_REASON_QSTA_LEAVE_QBSS, tx);
 118         }
 119 }
 120
 121 void ieee80211_ba_session_work(struct work_struct *work)
 122 {
 123         struct sta_info *sta =
 124                 container_of(work, struct sta_info, ampdu_mlme.work);
 125         struct tid_ampdu_tx *tid_tx;
 126         int tid;
 127
 128         /*
 129          * When this flag is set, new sessions should be
 130          * blocked, and existing sessions will be torn
 131          * down by the code that set the flag, so this
 132          * need not run.
 133          */
 134         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA))
 135                 return;
 136
 137         mutex_lock(&sta->ampdu_mlme.mtx);
 138         for (tid = 0; tid < STA_TID_NUM; tid++) {
 139                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 140                         ___ieee80211_stop_rx_ba_session(
 141                                 sta, tid, WLAN_BACK_RECIPIENT,
 142                                 WLAN_REASON_QSTA_TIMEOUT, true);
 143
 144                 if (test_and_clear_bit(tid,
 145                                        sta->ampdu_mlme.tid_rx_stop_requested))
 146                         ___ieee80211_stop_rx_ba_session(
 147                                 sta, tid, WLAN_BACK_RECIPIENT,
 148                                 WLAN_REASON_UNSPECIFIED, true);
 149
 150                 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 151                 if (tid_tx) {
 152                         /*
 153                          * Assign it over to the normal tid_tx array
 154                          * where it "goes live".
 155                          */
 156                         spin_lock_bh(&sta->lock);
 157
 158                         sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 159                         /* could there be a race? */
 160                         if (sta->ampdu_mlme.tid_tx[tid])
 161                                 kfree(tid_tx);
 162                         else
 163                                 ieee80211_assign_tid_tx(sta, tid, tid_tx);
 164                         spin_unlock_bh(&sta->lock);
 165
 166                         ieee80211_tx_ba_session_handle_start(sta, tid);
 167                         continue;
 168                 }
 169
 170                 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 171                 if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 172                                                  &tid_tx->state))
 173                         ___ieee80211_stop_tx_ba_session(sta, tid,
 174                                                         WLAN_BACK_INITIATOR,
 175                                                         true);
 176         }
 177         mutex_unlock(&sta->ampdu_mlme.mtx);
 178 }
 179
 180 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 181                           const u8 *da, u16 tid,
 182                           u16 initiator, u16 reason_code)
 183 {
 184         struct ieee80211_local *local = sdata->local;
 185         struct sk_buff *skb;
 186         struct ieee80211_mgmt *mgmt;
 187         u16 params;
 188
 189         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 190         if (!skb)
 191                 return;
 192
 193         skb_reserve(skb, local->hw.extra_tx_headroom);
 194         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 195         memset(mgmt, 0, 24);
 196         memcpy(mgmt->da, da, ETH_ALEN);
 197         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 198         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 199             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 200                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 201         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 202                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 203
 204         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 205                                           IEEE80211_STYPE_ACTION);
 206
 207         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 208
 209         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 210         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 211         params = (u16)(initiator << 11);        /* bit 11 initiator */
 212         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 213
 214         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 215         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 216
 217         ieee80211_tx_skb(sdata, skb);
 218 }
 219
 220 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 221                              struct sta_info *sta,
 222                              struct ieee80211_mgmt *mgmt, size_t len)
 223 {
 224         u16 tid, params;
 225         u16 initiator;
 226
 227         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 228         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 229         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 230
 231 #ifdef CONFIG_MAC80211_HT_DEBUG
 232         if (net_ratelimit())
 233                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 234                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 235                         le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 236 #endif /* CONFIG_MAC80211_HT_DEBUG */
 237
 238         if (initiator == WLAN_BACK_INITIATOR)
 239                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
 240                                                true);
 241         else
 242                 __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
 243                                                true);
 244 }
 245
 246 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 247                                enum ieee80211_smps_mode smps, const u8 *da,
 248                                const u8 *bssid)
 249 {
 250         struct ieee80211_local *local = sdata->local;
 251         struct sk_buff *skb;
 252         struct ieee80211_mgmt *action_frame;
 253
 254         /* 27 = header + category + action + smps mode */
 255         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 256         if (!skb)
 257                 return -ENOMEM;
 258
 259         skb_reserve(skb, local->hw.extra_tx_headroom);
 260         action_frame = (void *)skb_put(skb, 27);
 261         memcpy(action_frame->da, da, ETH_ALEN);
 262         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 263         memcpy(action_frame->bssid, bssid, ETH_ALEN);
 264         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 265                                                   IEEE80211_STYPE_ACTION);
 266         action_frame->u.action.category = WLAN_CATEGORY_HT;
 267         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 268         switch (smps) {
 269         case IEEE80211_SMPS_AUTOMATIC:
 270         case IEEE80211_SMPS_NUM_MODES:
 271                 WARN_ON(1);
 272         case IEEE80211_SMPS_OFF:
 273                 action_frame->u.action.u.ht_smps.smps_control =
 274                                 WLAN_HT_SMPS_CONTROL_DISABLED;
 275                 break;
 276         case IEEE80211_SMPS_STATIC:
 277                 action_frame->u.action.u.ht_smps.smps_control =
 278                                 WLAN_HT_SMPS_CONTROL_STATIC;
 279                 break;
 280         case IEEE80211_SMPS_DYNAMIC:
 281                 action_frame->u.action.u.ht_smps.smps_control =
 282                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
 283                 break;
 284         }
 285
 286         /* we'll do more on status of this frame */
 287         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 288         ieee80211_tx_skb(sdata, skb);
 289
 290         return 0;
 291 }
 292
 293 void ieee80211_request_smps_work(struct work_struct *work)
 294 {
 295         struct ieee80211_sub_if_data *sdata =
 296                 container_of(work, struct ieee80211_sub_if_data,
 297                              u.mgd.request_smps_work);
 298
 299         mutex_lock(&sdata->u.mgd.mtx);
 300         __ieee80211_request_smps(sdata, sdata->u.mgd.driver_smps_mode);
 301         mutex_unlock(&sdata->u.mgd.mtx);
 302 }
 303
 304 void ieee80211_request_smps(struct ieee80211_vif *vif,
 305                             enum ieee80211_smps_mode smps_mode)
 306 {
 307         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 308
 309         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 310                 return;
 311
 312         if (WARN_ON(smps_mode == IEEE80211_SMPS_OFF))
 313                 smps_mode = IEEE80211_SMPS_AUTOMATIC;
 314
 315         sdata->u.mgd.driver_smps_mode = smps_mode;
 316
 317         ieee80211_queue_work(&sdata->local->hw,
 318                              &sdata->u.mgd.request_smps_work);
 319 }
 320 /* this might change ... don't want non-open drivers using it */
 321 EXPORT_SYMBOL_GPL(ieee80211_request_smps);