From 9a955be695c839a23b43bba06ee824f0fbc76e1b Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sun, 5 Aug 2012 18:31:46 +0200 Subject: iwlwifi: disable greenfield transmissions as a workaround commit 50e2a30cf6fcaeb2d27360ba614dd169a10041c5 upstream. There's a bug that causes the rate scaling to get stuck when it has to use single-stream rates with a peer that can do GF and SGI; the two are incompatible so we can't use them together, but that causes the algorithm to not work at all, it always rejects updates. Disable greenfield for now to prevent that problem. Reviewed-by: Emmanuel Grumbach Tested-by: Cesar Eduardo Barros Signed-off-by: Johannes Berg Signed-off-by: John W. Linville [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings --- drivers/net/wireless/iwlwifi/iwl-agn-rs.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c index 9ba2c1bd78f4..339502580fd6 100644 --- a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c +++ b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c @@ -708,11 +708,14 @@ static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags, */ static bool rs_use_green(struct ieee80211_sta *sta) { - struct iwl_station_priv *sta_priv = (void *)sta->drv_priv; - struct iwl_rxon_context *ctx = sta_priv->ctx; - - return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) && - !(ctx->ht.non_gf_sta_present); + /* + * There's a bug somewhere in this code that causes the + * scaling to get stuck because GF+SGI can't be combined + * in SISO rates. Until we find that bug, disable GF, it + * has only limited benefit and we still interoperate with + * GF APs since we can always receive GF transmissions. + */ + return false; } /** -- cgit v1.2.3