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 <net/mac80211.h>
  18 #include "ieee80211_i.h"
  19 #include "rate.h"
  20
  21 void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
  22                                        struct ieee80211_ht_cap *ht_cap_ie,
  23                                        struct ieee80211_sta_ht_cap *ht_cap)
  24 {
  25         u8 ampdu_info, tx_mcs_set_cap;
  26         int i, max_tx_streams;
  27
  28         BUG_ON(!ht_cap);
  29
  30         memset(ht_cap, 0, sizeof(*ht_cap));
  31
  32         if (!ht_cap_ie || !sband->ht_cap.ht_supported)
  33                 return;
  34
  35         ht_cap->ht_supported = true;
  36
  37         /*
  38          * The bits listed in this expression should be
  39          * the same for the peer and us, if the station
  40          * advertises more then we can't use those thus
  41          * we mask them out.
  42          */
  43         ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) &
  44                 (sband->ht_cap.cap |
  45                  ~(IEEE80211_HT_CAP_LDPC_CODING |
  46                    IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
  47                    IEEE80211_HT_CAP_GRN_FLD |
  48                    IEEE80211_HT_CAP_SGI_20 |
  49                    IEEE80211_HT_CAP_SGI_40 |
  50                    IEEE80211_HT_CAP_DSSSCCK40));
  51         /*
  52          * The STBC bits are asymmetric -- if we don't have
  53          * TX then mask out the peer's RX and vice versa.
  54          */
  55         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_TX_STBC))
  56                 ht_cap->cap &= ~IEEE80211_HT_CAP_RX_STBC;
  57         if (!(sband->ht_cap.cap & IEEE80211_HT_CAP_RX_STBC))
  58                 ht_cap->cap &= ~IEEE80211_HT_CAP_TX_STBC;
  59
  60         ampdu_info = ht_cap_ie->ampdu_params_info;
  61         ht_cap->ampdu_factor =
  62                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
  63         ht_cap->ampdu_density =
  64                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
  65
  66         /* own MCS TX capabilities */
  67         tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;
  68
  69         /* can we TX with MCS rates? */
  70         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
  71                 return;
  72
  73         /* Counting from 0, therefore +1 */
  74         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
  75                 max_tx_streams =
  76                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
  77                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
  78         else
  79                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
  80
  81         /*
  82          * 802.11n D5.0 20.3.5 / 20.6 says:
  83          * - indices 0 to 7 and 32 are single spatial stream
  84          * - 8 to 31 are multiple spatial streams using equal modulation
  85          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
  86          * - remainder are multiple spatial streams using unequal modulation
  87          */
  88         for (i = 0; i < max_tx_streams; i++)
  89                 ht_cap->mcs.rx_mask[i] =
  90                         sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
  91
  92         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
  93                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
  94                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
  95                         ht_cap->mcs.rx_mask[i] =
  96                                 sband->ht_cap.mcs.rx_mask[i] &
  97                                         ht_cap_ie->mcs.rx_mask[i];
  98
  99         /* handle MCS rate 32 too */
 100         if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 101                 ht_cap->mcs.rx_mask[32/8] |= 1;
 102 }
 103
 104 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta)
 105 {
 106         int i;
 107
 108         cancel_work_sync(&sta->ampdu_mlme.work);
 109
 110         for (i = 0; i <  STA_TID_NUM; i++) {
 111                 __ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR);
 112                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
 113                                                WLAN_REASON_QSTA_LEAVE_QBSS);
 114         }
 115 }
 116
 117 void ieee80211_ba_session_work(struct work_struct *work)
 118 {
 119         struct sta_info *sta =
 120                 container_of(work, struct sta_info, ampdu_mlme.work);
 121         struct tid_ampdu_tx *tid_tx;
 122         int tid;
 123
 124         /*
 125          * When this flag is set, new sessions should be
 126          * blocked, and existing sessions will be torn
 127          * down by the code that set the flag, so this
 128          * need not run.
 129          */
 130         if (test_sta_flags(sta, WLAN_STA_BLOCK_BA))
 131                 return;
 132
 133         mutex_lock(&sta->ampdu_mlme.mtx);
 134         for (tid = 0; tid < STA_TID_NUM; tid++) {
 135                 if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 136                         ___ieee80211_stop_rx_ba_session(
 137                                 sta, tid, WLAN_BACK_RECIPIENT,
 138                                 WLAN_REASON_QSTA_TIMEOUT);
 139
 140                 tid_tx = sta->ampdu_mlme.tid_tx[tid];
 141                 if (!tid_tx)
 142                         continue;
 143
 144                 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state))
 145                         ieee80211_tx_ba_session_handle_start(sta, tid);
 146                 else if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 147                                             &tid_tx->state))
 148                         ___ieee80211_stop_tx_ba_session(sta, tid,
 149                                                         WLAN_BACK_INITIATOR);
 150         }
 151         mutex_unlock(&sta->ampdu_mlme.mtx);
 152 }
 153
 154 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 155                           const u8 *da, u16 tid,
 156                           u16 initiator, u16 reason_code)
 157 {
 158         struct ieee80211_local *local = sdata->local;
 159         struct sk_buff *skb;
 160         struct ieee80211_mgmt *mgmt;
 161         u16 params;
 162
 163         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 164
 165         if (!skb) {
 166                 printk(KERN_ERR "%s: failed to allocate buffer "
 167                                         "for delba frame\n", sdata->name);
 168                 return;
 169         }
 170
 171         skb_reserve(skb, local->hw.extra_tx_headroom);
 172         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 173         memset(mgmt, 0, 24);
 174         memcpy(mgmt->da, da, ETH_ALEN);
 175         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 176         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 177             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 178                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 179         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 180                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 181
 182         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 183                                           IEEE80211_STYPE_ACTION);
 184
 185         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 186
 187         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 188         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 189         params = (u16)(initiator << 11);        /* bit 11 initiator */
 190         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 191
 192         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 193         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 194
 195         ieee80211_tx_skb(sdata, skb);
 196 }
 197
 198 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 199                              struct sta_info *sta,
 200                              struct ieee80211_mgmt *mgmt, size_t len)
 201 {
 202         u16 tid, params;
 203         u16 initiator;
 204
 205         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 206         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 207         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 208
 209 #ifdef CONFIG_MAC80211_HT_DEBUG
 210         if (net_ratelimit())
 211                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 212                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 213                         le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 214 #endif /* CONFIG_MAC80211_HT_DEBUG */
 215
 216         if (initiator == WLAN_BACK_INITIATOR)
 217                 __ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0);
 218         else
 219                 __ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT);
 220 }
 221
 222 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 223                                enum ieee80211_smps_mode smps, const u8 *da,
 224                                const u8 *bssid)
 225 {
 226         struct ieee80211_local *local = sdata->local;
 227         struct sk_buff *skb;
 228         struct ieee80211_mgmt *action_frame;
 229
 230         /* 27 = header + category + action + smps mode */
 231         skb = dev_alloc_skb(27 + local->hw.extra_tx_headroom);
 232         if (!skb)
 233                 return -ENOMEM;
 234
 235         skb_reserve(skb, local->hw.extra_tx_headroom);
 236         action_frame = (void *)skb_put(skb, 27);
 237         memcpy(action_frame->da, da, ETH_ALEN);
 238         memcpy(action_frame->sa, sdata->dev->dev_addr, ETH_ALEN);
 239         memcpy(action_frame->bssid, bssid, ETH_ALEN);
 240         action_frame->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 241                                                   IEEE80211_STYPE_ACTION);
 242         action_frame->u.action.category = WLAN_CATEGORY_HT;
 243         action_frame->u.action.u.ht_smps.action = WLAN_HT_ACTION_SMPS;
 244         switch (smps) {
 245         case IEEE80211_SMPS_AUTOMATIC:
 246         case IEEE80211_SMPS_NUM_MODES:
 247                 WARN_ON(1);
 248         case IEEE80211_SMPS_OFF:
 249                 action_frame->u.action.u.ht_smps.smps_control =
 250                                 WLAN_HT_SMPS_CONTROL_DISABLED;
 251                 break;
 252         case IEEE80211_SMPS_STATIC:
 253                 action_frame->u.action.u.ht_smps.smps_control =
 254                                 WLAN_HT_SMPS_CONTROL_STATIC;
 255                 break;
 256         case IEEE80211_SMPS_DYNAMIC:
 257                 action_frame->u.action.u.ht_smps.smps_control =
 258                                 WLAN_HT_SMPS_CONTROL_DYNAMIC;
 259                 break;
 260         }
 261
 262         /* we'll do more on status of this frame */
 263         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
 264         ieee80211_tx_skb(sdata, skb);
 265
 266         return 0;
 267 }