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 2007-2008, 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)
  33                 return;
  34
  35         ht_cap->ht_supported = true;
  36
  37         ht_cap->cap = le16_to_cpu(ht_cap_ie->cap_info) & sband->ht_cap.cap;
  38         ht_cap->cap &= ~IEEE80211_HT_CAP_SM_PS;
  39         ht_cap->cap |= sband->ht_cap.cap & IEEE80211_HT_CAP_SM_PS;
  40
  41         ampdu_info = ht_cap_ie->ampdu_params_info;
  42         ht_cap->ampdu_factor =
  43                 ampdu_info & IEEE80211_HT_AMPDU_PARM_FACTOR;
  44         ht_cap->ampdu_density =
  45                 (ampdu_info & IEEE80211_HT_AMPDU_PARM_DENSITY) >> 2;
  46
  47         /* own MCS TX capabilities */
  48         tx_mcs_set_cap = sband->ht_cap.mcs.tx_params;
  49
  50         /* can we TX with MCS rates? */
  51         if (!(tx_mcs_set_cap & IEEE80211_HT_MCS_TX_DEFINED))
  52                 return;
  53
  54         /* Counting from 0, therefore +1 */
  55         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_RX_DIFF)
  56                 max_tx_streams =
  57                         ((tx_mcs_set_cap & IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
  58                                 >> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT) + 1;
  59         else
  60                 max_tx_streams = IEEE80211_HT_MCS_TX_MAX_STREAMS;
  61
  62         /*
  63          * 802.11n D5.0 20.3.5 / 20.6 says:
  64          * - indices 0 to 7 and 32 are single spatial stream
  65          * - 8 to 31 are multiple spatial streams using equal modulation
  66          *   [8..15 for two streams, 16..23 for three and 24..31 for four]
  67          * - remainder are multiple spatial streams using unequal modulation
  68          */
  69         for (i = 0; i < max_tx_streams; i++)
  70                 ht_cap->mcs.rx_mask[i] =
  71                         sband->ht_cap.mcs.rx_mask[i] & ht_cap_ie->mcs.rx_mask[i];
  72
  73         if (tx_mcs_set_cap & IEEE80211_HT_MCS_TX_UNEQUAL_MODULATION)
  74                 for (i = IEEE80211_HT_MCS_UNEQUAL_MODULATION_START_BYTE;
  75                      i < IEEE80211_HT_MCS_MASK_LEN; i++)
  76                         ht_cap->mcs.rx_mask[i] =
  77                                 sband->ht_cap.mcs.rx_mask[i] &
  78                                         ht_cap_ie->mcs.rx_mask[i];
  79
  80         /* handle MCS rate 32 too */
  81         if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
  82                 ht_cap->mcs.rx_mask[32/8] |= 1;
  83 }
  84
  85 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta)
  86 {
  87         int i;
  88
  89         for (i = 0; i <  STA_TID_NUM; i++) {
  90                 __ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR);
  91                 __ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
  92                                                WLAN_REASON_QSTA_LEAVE_QBSS);
  93         }
  94 }
  95
  96 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
  97                           const u8 *da, u16 tid,
  98                           u16 initiator, u16 reason_code)
  99 {
 100         struct ieee80211_local *local = sdata->local;
 101         struct sk_buff *skb;
 102         struct ieee80211_mgmt *mgmt;
 103         u16 params;
 104
 105         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 106
 107         if (!skb) {
 108                 printk(KERN_ERR "%s: failed to allocate buffer "
 109                                         "for delba frame\n", sdata->dev->name);
 110                 return;
 111         }
 112
 113         skb_reserve(skb, local->hw.extra_tx_headroom);
 114         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 115         memset(mgmt, 0, 24);
 116         memcpy(mgmt->da, da, ETH_ALEN);
 117         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 118         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 119             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 120                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
 121         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 122                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 123
 124         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 125                                           IEEE80211_STYPE_ACTION);
 126
 127         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 128
 129         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 130         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 131         params = (u16)(initiator << 11);        /* bit 11 initiator */
 132         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 133
 134         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 135         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 136
 137         ieee80211_tx_skb(sdata, skb, 1);
 138 }
 139
 140 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 141                              struct sta_info *sta,
 142                              struct ieee80211_mgmt *mgmt, size_t len)
 143 {
 144         struct ieee80211_local *local = sdata->local;
 145         u16 tid, params;
 146         u16 initiator;
 147
 148         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 149         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 150         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 151
 152 #ifdef CONFIG_MAC80211_HT_DEBUG
 153         if (net_ratelimit())
 154                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 155                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 156                         le16_to_cpu(mgmt->u.action.u.delba.reason_code));
 157 #endif /* CONFIG_MAC80211_HT_DEBUG */
 158
 159         if (initiator == WLAN_BACK_INITIATOR)
 160                 ieee80211_sta_stop_rx_ba_session(sdata, sta->sta.addr, tid,
 161                                                  WLAN_BACK_INITIATOR, 0);
 162         else { /* WLAN_BACK_RECIPIENT */
 163                 spin_lock_bh(&sta->lock);
 164                 sta->ampdu_mlme.tid_state_tx[tid] =
 165                                 HT_AGG_STATE_OPERATIONAL;
 166                 spin_unlock_bh(&sta->lock);
 167                 ieee80211_stop_tx_ba_session(&local->hw, sta->sta.addr, tid,
 168                                              WLAN_BACK_RECIPIENT);
 169         }
 170 }