From 6e6cc9f319bf81b292ceb281228ab1d261172cac Mon Sep 17 00:00:00 2001 From: Beni Lev Date: Tue, 19 Feb 2013 14:40:11 +0200 Subject: [PATCH] iwlwifi: disable greenfield transmissions as a workaround 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. The MVM driver currently only works on devices that don't support greenfield anyway, but better be safe and not allow us to forget about this. Signed-off-by: Beni Lev Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- drivers/net/wireless/iwlwifi/mvm/rs.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/mvm/rs.c b/drivers/net/wireless/iwlwifi/mvm/rs.c index 56b636d9ab30..a01a6612677e 100644 --- a/drivers/net/wireless/iwlwifi/mvm/rs.c +++ b/drivers/net/wireless/iwlwifi/mvm/rs.c @@ -680,12 +680,14 @@ static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags, */ static bool rs_use_green(struct ieee80211_sta *sta) { - struct iwl_mvm_sta *sta_priv = (void *)sta->drv_priv; - - bool use_green = !(sta_priv->vif->bss_conf.ht_operation_mode & - IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT); - - return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) && use_green; + /* + * 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; } /** -- 2.20.1