iwlwifi: use station HT capabilities and BSS operating mode for Green-field

Green-field mode should be configured in the HT station table.  This patch uses
both the per-station GF support flag as well as the current BSS HT operation
mode (non-GF stations present flag).

Added the "ht_greenfield_support" field to struct iwl_cfg to replace the
device-specific check in rs_use_green().  That check has been moved to
iwlcore_init_ht_hw_capab().

Signed-off-by: Daniel C Halperin <daniel.c.halperin@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 15 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
index 3b1bbc394a49..fee110de5c6a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
@@ -657,19 +657,15 @@ static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
         return 1;
 }
 
-/* in 4965 we don't use greenfield at all */
-static inline u8 rs_use_green(struct iwl_priv *priv,
-                              struct ieee80211_conf *conf)
+/**
+ * Green-field mode is valid if the station supports it and
+ * there are no non-GF stations present in the BSS.
+ */
+static inline u8 rs_use_green(struct ieee80211_sta *sta,
+                              struct iwl_ht_info *ht_conf)
 {
-        u8 is_green;
-
-        if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
-                is_green = 0;
-        else
-                is_green = (conf_is_ht(conf) &&
-                           priv->current_ht_config.is_green_field &&
-                           !priv->current_ht_config.non_GF_STA_present);
-        return is_green;
+        return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
+                !(ht_conf->non_GF_STA_present);
 }
 
 /**
@@ -2072,7 +2068,7 @@ static void rs_rate_scale_perform(struct iwl_priv *priv,
         if (is_legacy(tbl->lq_type))
                 lq_sta->is_green = 0;
         else
-                lq_sta->is_green = rs_use_green(priv, conf);
+                lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
         is_green = lq_sta->is_green;
 
         /* current tx rate */
@@ -2430,7 +2426,7 @@ static void rs_initialize_lq(struct iwl_priv *priv,
         int rate_idx;
         int i;
         u32 rate;
-        u8 use_green = rs_use_green(priv, conf);
+        u8 use_green = rs_use_green(sta, &priv->current_ht_config);
         u8 active_tbl = 0;
         u8 valid_tx_ant;
 
@@ -2627,7 +2623,7 @@ static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
         lq_sta->is_dup = 0;
         lq_sta->max_rate_idx = -1;
         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
-        lq_sta->is_green = rs_use_green(priv, conf);
+        lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
         lq_sta->active_rate_basic = priv->active_rate_basic;
         lq_sta->band = priv->band;