package/kernel/mac80211/patches/306-mac80211-minstrel-Enable-STBC-and-LDPC-for-VHT-Rates.patch

   1 From: Chaitanya T K <chaitanya.mgit@gmail.com>
   2 Date: Mon, 27 Jun 2016 15:23:26 +0530
   3 Subject: [PATCH] mac80211: minstrel: Enable STBC and LDPC for VHT Rates
   4
   5 If peer support reception of STBC and LDPC, enable them for better
   6 performance.
   7
   8 Signed-off-by: Chaitanya TK <chaitanya.mgit@gmail.com>
   9 ---
  10
  11 --- a/include/linux/ieee80211.h
  12 +++ b/include/linux/ieee80211.h
  13 @@ -1551,6 +1551,7 @@ struct ieee80211_vht_operation {
  14  #define IEEE80211_VHT_CAP_RXSTBC_3                             0x00000300
  15  #define IEEE80211_VHT_CAP_RXSTBC_4                             0x00000400
  16  #define IEEE80211_VHT_CAP_RXSTBC_MASK                          0x00000700
  17 +#define IEEE80211_VHT_CAP_RXSTBC_SHIFT                         8
  18  #define IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE                        0x00000800
  19  #define IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE                        0x00001000
  20  #define IEEE80211_VHT_CAP_BEAMFORMEE_STS_SHIFT                  13
  21 --- a/net/mac80211/rc80211_minstrel_ht.c
  22 +++ b/net/mac80211/rc80211_minstrel_ht.c
  23 @@ -1166,13 +1166,14 @@ minstrel_ht_update_caps(void *priv, stru
  24         struct minstrel_ht_sta_priv *msp = priv_sta;
  25         struct minstrel_ht_sta *mi = &msp->ht;
  26         struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
  27 -       u16 sta_cap = sta->ht_cap.cap;
  28 +       u16 ht_cap = sta->ht_cap.cap;
  29         struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
  30         int use_vht;
  31         int n_supported = 0;
  32         int ack_dur;
  33         int stbc;
  34         int i;
  35 +       bool ldpc = false;
  36
  37         /* fall back to the old minstrel for legacy stations */
  38         if (!sta->ht_cap.ht_supported)
  39 @@ -1210,16 +1211,24 @@ minstrel_ht_update_caps(void *priv, stru
  40         }
  41         mi->sample_tries = 4;
  42
  43 -       /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */
  44         if (!use_vht) {
  45 -               stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
  46 +               stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >>
  47                         IEEE80211_HT_CAP_RX_STBC_SHIFT;
  48 -               mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
  49
  50 -               if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
  51 -                       mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
  52 +               if (ht_cap & IEEE80211_HT_CAP_LDPC_CODING)
  53 +                       ldpc = true;
  54 +       } else {
  55 +               stbc = (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK) >>
  56 +                       IEEE80211_VHT_CAP_RXSTBC_SHIFT;
  57 +
  58 +               if (vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC)
  59 +                       ldpc = true;
  60         }
  61
  62 +       mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
  63 +       if (ldpc)
  64 +               mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
  65 +
  66         for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
  67                 u32 gflags = minstrel_mcs_groups[i].flags;
  68                 int bw, nss;
  69 @@ -1232,10 +1241,10 @@ minstrel_ht_update_caps(void *priv, stru
  70
  71                 if (gflags & IEEE80211_TX_RC_SHORT_GI) {
  72                         if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
  73 -                               if (!(sta_cap & IEEE80211_HT_CAP_SGI_40))
  74 +                               if (!(ht_cap & IEEE80211_HT_CAP_SGI_40))
  75                                         continue;
  76                         } else {
  77 -                               if (!(sta_cap & IEEE80211_HT_CAP_SGI_20))
  78 +                               if (!(ht_cap & IEEE80211_HT_CAP_SGI_20))
  79                                         continue;
  80                         }
  81                 }