package/mac80211/patches/414-mac80211-slot-time.patch

   1 Subject: mac80211: fix short slot handling
   2
   3 This patch makes mac80211 handle short slot requests from the AP
   4 properly. Also warn about uses of IEEE80211_CONF_SHORT_SLOT_TIME
   5 and optimise out the code since it cannot ever be hit anyway.
   6
   7 Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
   8 ---
   9  include/net/mac80211.h |   28 ++++++++++--------
  10  net/mac80211/main.c    |    9 +++--
  11  net/mac80211/mlme.c    |   74 ++++++++++++++++++++++++++-----------------------
  12  3 files changed, 62 insertions(+), 49 deletions(-)
  13
  14 --- everything.orig/net/mac80211/main.c 2008-10-07 20:06:43.000000000 +0200
  15 +++ everything/net/mac80211/main.c      2008-10-08 10:56:29.000000000 +0200
  16 @@ -346,9 +346,12 @@ void ieee80211_bss_info_change_notify(st
  17
  18  u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
  19  {
  20 -       sdata->bss_conf.use_cts_prot = 0;
  21 -       sdata->bss_conf.use_short_preamble = 0;
  22 -       return BSS_CHANGED_ERP_CTS_PROT | BSS_CHANGED_ERP_PREAMBLE;
  23 +       sdata->bss_conf.use_cts_prot = false;
  24 +       sdata->bss_conf.use_short_preamble = false;
  25 +       sdata->bss_conf.use_short_slot = false;
  26 +       return BSS_CHANGED_ERP_CTS_PROT |
  27 +              BSS_CHANGED_ERP_PREAMBLE |
  28 +              BSS_CHANGED_ERP_SLOT;
  29  }
  30
  31  void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  32 --- everything.orig/net/mac80211/mlme.c 2008-10-07 20:05:49.000000000 +0200
  33 +++ everything/net/mac80211/mlme.c      2008-10-08 10:56:38.000000000 +0200
  34 @@ -568,9 +568,8 @@ static void ieee80211_sta_wmm_params(str
  35         }
  36  }
  37
  38 -static u32 ieee80211_handle_protect_preamb(struct ieee80211_sub_if_data *sdata,
  39 -                                          bool use_protection,
  40 -                                          bool use_short_preamble)
  41 +static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
  42 +                                          u16 capab, bool erp_valid, u8 erp)
  43  {
  44         struct ieee80211_bss_conf *bss_conf = &sdata->bss_conf;
  45  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  46 @@ -578,6 +577,19 @@ static u32 ieee80211_handle_protect_prea
  47         DECLARE_MAC_BUF(mac);
  48  #endif
  49         u32 changed = 0;
  50 +       bool use_protection;
  51 +       bool use_short_preamble;
  52 +       bool use_short_slot;
  53 +
  54 +       if (erp_valid) {
  55 +               use_protection = (erp & WLAN_ERP_USE_PROTECTION) != 0;
  56 +               use_short_preamble = (erp & WLAN_ERP_BARKER_PREAMBLE) == 0;
  57 +       } else {
  58 +               use_protection = false;
  59 +               use_short_preamble = !!(capab & WLAN_CAPABILITY_SHORT_PREAMBLE);
  60 +       }
  61 +
  62 +       use_short_slot = !!(capab & WLAN_CAPABILITY_SHORT_SLOT_TIME);
  63
  64         if (use_protection != bss_conf->use_cts_prot) {
  65  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  66 @@ -607,30 +619,18 @@ static u32 ieee80211_handle_protect_prea
  67                 changed |= BSS_CHANGED_ERP_PREAMBLE;
  68         }
  69
  70 -       return changed;
  71 -}
  72 -
  73 -static u32 ieee80211_handle_erp_ie(struct ieee80211_sub_if_data *sdata,
  74 -                                  u8 erp_value)
  75 -{
  76 -       bool use_protection = (erp_value & WLAN_ERP_USE_PROTECTION) != 0;
  77 -       bool use_short_preamble = (erp_value & WLAN_ERP_BARKER_PREAMBLE) == 0;
  78 -
  79 -       return ieee80211_handle_protect_preamb(sdata,
  80 -                       use_protection, use_short_preamble);
  81 -}
  82 -
  83 -static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
  84 -                                          struct ieee80211_bss *bss)
  85 -{
  86 -       u32 changed = 0;
  87 -
  88 -       if (bss->has_erp_value)
  89 -               changed |= ieee80211_handle_erp_ie(sdata, bss->erp_value);
  90 -       else {
  91 -               u16 capab = bss->capability;
  92 -               changed |= ieee80211_handle_protect_preamb(sdata, false,
  93 -                               (capab & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0);
  94 +       if (use_short_slot != bss_conf->use_short_slot) {
  95 +#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  96 +               if (net_ratelimit()) {
  97 +                       printk(KERN_DEBUG "%s: switched to %s slot"
  98 +                              " (BSSID=%s)\n",
  99 +                              sdata->dev->name,
 100 +                              use_short_slot ? "short" : "long",
 101 +                              print_mac(mac, ifsta->bssid));
 102 +               }
 103 +#endif
 104 +               bss_conf->use_short_slot = use_short_slot;
 105 +               changed |= BSS_CHANGED_ERP_SLOT;
 106         }
 107
 108         return changed;
 109 @@ -723,7 +723,8 @@ static void ieee80211_set_associated(str
 110                 sdata->bss_conf.timestamp = bss->timestamp;
 111                 sdata->bss_conf.dtim_period = bss->dtim_period;
 112
 113 -               changed |= ieee80211_handle_bss_capability(sdata, bss);
 114 +               changed |= ieee80211_handle_bss_capability(sdata,
 115 +                       bss->capability, bss->has_erp_value, bss->erp_value);
 116
 117                 ieee80211_rx_bss_put(local, bss);
 118         }
 119 @@ -1675,6 +1676,8 @@ static void ieee80211_rx_mgmt_beacon(str
 120         struct ieee80211_local *local = sdata->local;
 121         struct ieee80211_conf *conf = &local->hw.conf;
 122         u32 changed = 0;
 123 +       bool erp_valid;
 124 +       u8 erp_value = 0;
 125
 126         /* Process beacon from the current BSS */
 127         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 128 @@ -1696,13 +1699,16 @@ static void ieee80211_rx_mgmt_beacon(str
 129         ieee80211_sta_wmm_params(local, ifsta, elems.wmm_param,
 130                                  elems.wmm_param_len);
 131
 132 -       if (elems.erp_info && elems.erp_info_len >= 1)
 133 -               changed |= ieee80211_handle_erp_ie(sdata, elems.erp_info[0]);
 134 -       else {
 135 -               u16 capab = le16_to_cpu(mgmt->u.beacon.capab_info);
 136 -               changed |= ieee80211_handle_protect_preamb(sdata, false,
 137 -                               (capab & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0);
 138 +
 139 +       if (elems.erp_info && elems.erp_info_len >= 1) {
 140 +               erp_valid = true;
 141 +               erp_value = elems.erp_info[0];
 142 +       } else {
 143 +               erp_valid = false;
 144         }
 145 +       changed |= ieee80211_handle_bss_capability(sdata,
 146 +                       le16_to_cpu(mgmt->u.beacon.capab_info),
 147 +                       erp_valid, erp_value);
 148
 149         if (elems.ht_cap_elem && elems.ht_info_elem &&
 150             elems.wmm_param && conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) {
 151 --- everything.orig/include/net/mac80211.h      2008-10-07 20:06:43.000000000 +0200
 152 +++ everything/include/net/mac80211.h   2008-10-08 10:57:06.000000000 +0200
 153 @@ -180,8 +180,12 @@ enum ieee80211_bss_change {
 154   * @assoc: association status
 155   * @aid: association ID number, valid only when @assoc is true
 156   * @use_cts_prot: use CTS protection
 157 - * @use_short_preamble: use 802.11b short preamble
 158 - * @use_short_slot: use short slot time (only relevant for ERP)
 159 + * @use_short_preamble: use 802.11b short preamble;
 160 + *     if the hardware cannot handle this it must set the
 161 + *     IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE hardware flag
 162 + * @use_short_slot: use short slot time (only relevant for ERP);
 163 + *     if the hardware cannot handle this it must set the
 164 + *     IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE hardware flag
 165   * @dtim_period: num of beacons before the next DTIM, for PSM
 166   * @timestamp: beacon timestamp
 167   * @beacon_int: beacon interval
 168 @@ -442,23 +446,23 @@ struct ieee80211_rx_status {
 169   *
 170   * Flags to define PHY configuration options
 171   *
 172 - * @IEEE80211_CONF_SHORT_SLOT_TIME: use 802.11g short slot time
 173   * @IEEE80211_CONF_RADIOTAP: add radiotap header at receive time (if supported)
 174   * @IEEE80211_CONF_SUPPORT_HT_MODE: use 802.11n HT capabilities (if supported)
 175   * @IEEE80211_CONF_PS: Enable 802.11 power save mode
 176   */
 177  enum ieee80211_conf_flags {
 178 -       /*
 179 -        * TODO: IEEE80211_CONF_SHORT_SLOT_TIME will be removed once drivers
 180 -        * have been converted to use bss_info_changed() for slot time
 181 -        * configuration
 182 -        */
 183 -       IEEE80211_CONF_SHORT_SLOT_TIME  = (1<<0),
 184 -       IEEE80211_CONF_RADIOTAP         = (1<<1),
 185 -       IEEE80211_CONF_SUPPORT_HT_MODE  = (1<<2),
 186 -       IEEE80211_CONF_PS               = (1<<3),
 187 +       IEEE80211_CONF_RADIOTAP         = (1<<0),
 188 +       IEEE80211_CONF_SUPPORT_HT_MODE  = (1<<1),
 189 +       IEEE80211_CONF_PS               = (1<<2),
 190  };
 191
 192 +/* XXX: remove all this once drivers stop trying to use it */
 193 +static inline int __deprecated __IEEE80211_CONF_SHORT_SLOT_TIME(void)
 194 +{
 195 +       return 0;
 196 +}
 197 +#define IEEE80211_CONF_SHORT_SLOT_TIME (__IEEE80211_CONF_SHORT_SLOT_TIME())
 198 +
 199  /**
 200   * struct ieee80211_conf - configuration of the device
 201   *