drivers/net/wireless/rtlwifi/rc.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2009-2010  Realtek Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  * wlanfae <wlanfae@realtek.com>
  23  * Realtek Corporation, No. 2, Innovation Road II, Hsinchu Science Park,
  24  * Hsinchu 300, Taiwan.
  25  *
  26  * Larry Finger <Larry.Finger@lwfinger.net>
  27  *
  28  *****************************************************************************/
  29
  30 #include "wifi.h"
  31 #include "base.h"
  32 #include "rc.h"
  33
  34 /*
  35  *Finds the highest rate index we can use
  36  *if skb is special data like DHCP/EAPOL, we set should
  37  *it to lowest rate CCK_1M, otherwise we set rate to
  38  *CCK11M or OFDM_54M based on wireless mode.
  39  */
  40 static u8 _rtl_rc_get_highest_rix(struct rtl_priv *rtlpriv,
  41                                   struct ieee80211_sta *sta,
  42                                   struct sk_buff *skb, bool not_data)
  43 {
  44         struct rtl_mac *rtlmac = rtl_mac(rtlpriv);
  45         struct rtl_hal *rtlhal = rtl_hal(rtlpriv);
  46         struct rtl_phy *rtlphy = &(rtlpriv->phy);
  47         struct rtl_sta_info *sta_entry = NULL;
  48         u8 wireless_mode = 0;
  49
  50         /*
  51          *this rate is no use for true rate, firmware
  52          *will control rate at all it just used for
  53          *1.show in iwconfig in B/G mode
  54          *2.in rtl_get_tcb_desc when we check rate is
  55          *      1M we will not use FW rate but user rate.
  56          */
  57         if (rtlmac->opmode == NL80211_IFTYPE_AP ||
  58                 rtlmac->opmode == NL80211_IFTYPE_ADHOC) {
  59                 if (sta) {
  60                         sta_entry = (struct rtl_sta_info *) sta->drv_priv;
  61                         wireless_mode = sta_entry->wireless_mode;
  62                 } else {
  63                         return 0;
  64                 }
  65         } else {
  66                 wireless_mode = rtlmac->mode;
  67         }
  68
  69         if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true) ||
  70                         not_data) {
  71                 return 0;
  72         } else {
  73                 if (rtlhal->current_bandtype == BAND_ON_2_4G) {
  74                         if (wireless_mode == WIRELESS_MODE_B) {
  75                                 return B_MODE_MAX_RIX;
  76                         } else if (wireless_mode == WIRELESS_MODE_G) {
  77                                 return G_MODE_MAX_RIX;
  78                         } else {
  79                                 if (get_rf_type(rtlphy) != RF_2T2R)
  80                                         return N_MODE_MCS7_RIX;
  81                                 else
  82                                         return N_MODE_MCS15_RIX;
  83                         }
  84                 } else {
  85                         if (wireless_mode == WIRELESS_MODE_A) {
  86                                 return A_MODE_MAX_RIX;
  87                         } else {
  88                                 if (get_rf_type(rtlphy) != RF_2T2R)
  89                                         return N_MODE_MCS7_RIX;
  90                                 else
  91                                         return N_MODE_MCS15_RIX;
  92                         }
  93                 }
  94         }
  95 }
  96
  97 static void _rtl_rc_rate_set_series(struct rtl_priv *rtlpriv,
  98                                     struct ieee80211_sta *sta,
  99                                     struct ieee80211_tx_rate *rate,
 100                                     struct ieee80211_tx_rate_control *txrc,
 101                                     u8 tries, char rix, int rtsctsenable,
 102                                     bool not_data)
 103 {
 104         struct rtl_mac *mac = rtl_mac(rtlpriv);
 105         u8 sgi_20 = 0, sgi_40 = 0;
 106
 107         if (sta) {
 108                 sgi_20 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20;
 109                 sgi_40 = sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40;
 110         }
 111         rate->count = tries;
 112         rate->idx = rix >= 0x00 ? rix : 0x00;
 113
 114         if (!not_data) {
 115                 if (txrc->short_preamble)
 116                         rate->flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
 117                 if (mac->opmode == NL80211_IFTYPE_AP ||
 118                         mac->opmode == NL80211_IFTYPE_ADHOC) {
 119                         if (sta && (sta->ht_cap.cap &
 120                             IEEE80211_HT_CAP_SUP_WIDTH_20_40))
 121                                 rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
 122                 } else {
 123                         if (mac->bw_40)
 124                                 rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
 125                 }
 126                 if (sgi_20 || sgi_40)
 127                         rate->flags |= IEEE80211_TX_RC_SHORT_GI;
 128                 if (sta && sta->ht_cap.ht_supported)
 129                         rate->flags |= IEEE80211_TX_RC_MCS;
 130         }
 131 }
 132
 133 static void rtl_get_rate(void *ppriv, struct ieee80211_sta *sta,
 134                          void *priv_sta, struct ieee80211_tx_rate_control *txrc)
 135 {
 136         struct rtl_priv *rtlpriv = ppriv;
 137         struct sk_buff *skb = txrc->skb;
 138         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
 139         struct ieee80211_tx_rate *rates = tx_info->control.rates;
 140         __le16 fc = rtl_get_fc(skb);
 141         u8 try_per_rate, i, rix;
 142         bool not_data = !ieee80211_is_data(fc);
 143
 144         if (rate_control_send_low(sta, priv_sta, txrc))
 145                 return;
 146
 147         rix = _rtl_rc_get_highest_rix(rtlpriv, sta, skb, not_data);
 148         try_per_rate = 1;
 149         _rtl_rc_rate_set_series(rtlpriv, sta, &rates[0], txrc,
 150                                 try_per_rate, rix, 1, not_data);
 151
 152         if (!not_data) {
 153                 for (i = 1; i < 4; i++)
 154                         _rtl_rc_rate_set_series(rtlpriv, sta, &rates[i],
 155                                                 txrc, i, (rix - i), 1,
 156                                                 not_data);
 157         }
 158 }
 159
 160 static bool _rtl_tx_aggr_check(struct rtl_priv *rtlpriv,
 161                 struct rtl_sta_info *sta_entry, u16 tid)
 162 {
 163         struct rtl_mac *mac = rtl_mac(rtlpriv);
 164
 165         if (mac->act_scanning)
 166                 return false;
 167
 168         if (mac->opmode == NL80211_IFTYPE_STATION &&
 169                 mac->cnt_after_linked < 3)
 170                 return false;
 171
 172         if (sta_entry->tids[tid].agg.agg_state == RTL_AGG_STOP)
 173                 return true;
 174
 175         return false;
 176 }
 177
 178 /*mac80211 Rate Control callbacks*/
 179 static void rtl_tx_status(void *ppriv,
 180                           struct ieee80211_supported_band *sband,
 181                           struct ieee80211_sta *sta, void *priv_sta,
 182                           struct sk_buff *skb)
 183 {
 184         struct rtl_priv *rtlpriv = ppriv;
 185         struct rtl_mac *mac = rtl_mac(rtlpriv);
 186         struct ieee80211_hdr *hdr = rtl_get_hdr(skb);
 187         __le16 fc = rtl_get_fc(skb);
 188         struct rtl_sta_info *sta_entry;
 189
 190         if (!priv_sta || !ieee80211_is_data(fc))
 191                 return;
 192
 193         if (rtl_is_special_data(mac->hw, skb, true))
 194                 return;
 195
 196         if (is_multicast_ether_addr(ieee80211_get_DA(hdr))
 197             || is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
 198                 return;
 199
 200         if (sta) {
 201                 /* Check if aggregation has to be enabled for this tid */
 202                 sta_entry = (struct rtl_sta_info *) sta->drv_priv;
 203                 if ((sta->ht_cap.ht_supported) &&
 204                                 !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
 205                         if (ieee80211_is_data_qos(fc)) {
 206                                 u8 tid = rtl_get_tid(skb);
 207                                 if (_rtl_tx_aggr_check(rtlpriv, sta_entry,
 208                                     tid)) {
 209                                         sta_entry->tids[tid].agg.agg_state =
 210                                                          RTL_AGG_PROGRESS;
 211                                         ieee80211_start_tx_ba_session(sta,
 212                                                                  tid, 5000);
 213                                 }
 214                         }
 215                 }
 216         }
 217 }
 218
 219 static void rtl_rate_init(void *ppriv,
 220                           struct ieee80211_supported_band *sband,
 221                           struct ieee80211_sta *sta, void *priv_sta)
 222 {
 223 }
 224
 225 static void rtl_rate_update(void *ppriv,
 226                             struct ieee80211_supported_band *sband,
 227                             struct ieee80211_sta *sta, void *priv_sta,
 228                             u32 changed,
 229                             enum nl80211_channel_type oper_chan_type)
 230 {
 231 }
 232
 233 static void *rtl_rate_alloc(struct ieee80211_hw *hw,
 234                 struct dentry *debugfsdir)
 235 {
 236         struct rtl_priv *rtlpriv = rtl_priv(hw);
 237         return rtlpriv;
 238 }
 239
 240 static void rtl_rate_free(void *rtlpriv)
 241 {
 242         return;
 243 }
 244
 245 static void *rtl_rate_alloc_sta(void *ppriv,
 246                                 struct ieee80211_sta *sta, gfp_t gfp)
 247 {
 248         struct rtl_priv *rtlpriv = ppriv;
 249         struct rtl_rate_priv *rate_priv;
 250
 251         rate_priv = kzalloc(sizeof(struct rtl_rate_priv), gfp);
 252         if (!rate_priv) {
 253                 RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
 254                          ("Unable to allocate private rc structure\n"));
 255                 return NULL;
 256         }
 257
 258         rtlpriv->rate_priv = rate_priv;
 259
 260         return rate_priv;
 261 }
 262
 263 static void rtl_rate_free_sta(void *rtlpriv,
 264                               struct ieee80211_sta *sta, void *priv_sta)
 265 {
 266         struct rtl_rate_priv *rate_priv = priv_sta;
 267         kfree(rate_priv);
 268 }
 269
 270 static struct rate_control_ops rtl_rate_ops = {
 271         .module = NULL,
 272         .name = "rtl_rc",
 273         .alloc = rtl_rate_alloc,
 274         .free = rtl_rate_free,
 275         .alloc_sta = rtl_rate_alloc_sta,
 276         .free_sta = rtl_rate_free_sta,
 277         .rate_init = rtl_rate_init,
 278         .rate_update = rtl_rate_update,
 279         .tx_status = rtl_tx_status,
 280         .get_rate = rtl_get_rate,
 281 };
 282
 283 int rtl_rate_control_register(void)
 284 {
 285         return ieee80211_rate_control_register(&rtl_rate_ops);
 286 }
 287
 288 void rtl_rate_control_unregister(void)
 289 {
 290         ieee80211_rate_control_unregister(&rtl_rate_ops);
 291 }