Return-path: Received: from mail-wi0-f175.google.com ([209.85.212.175]:37539 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932288AbaKXOgc (ORCPT ); Mon, 24 Nov 2014 09:36:32 -0500 Received: by mail-wi0-f175.google.com with SMTP id l15so5859214wiw.14 for ; Mon, 24 Nov 2014 06:36:31 -0800 (PST) From: Emmanuel Grumbach To: linux-wireless@vger.kernel.org Cc: Luciano Coelho Subject: [PATCH 58/75] iwlwifi: mvm: schedule CSA time event a bit before beacon 1 Date: Mon, 24 Nov 2014 16:34:34 +0200 Message-Id: <1416839691-28533-58-git-send-email-egrumbach@gmail.com> (sfid-20141124_153639_980007_CE1AA722) In-Reply-To: References: Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Luciano Coelho Instead of using a hardcoded number of TUs before beacon 0 as the time to start the absence and actual channel switch, calculate it in relation to the beacon interval. We use 10 TUs + beacon interval before beacon 0 to target a bit before beacon 1. This gives us enough time to switch to the new channel before the AP/GO switches. Signed-off-by: Luciano Coelho --- drivers/net/wireless/iwlwifi/mvm/mac80211.c | 12 ++++++++---- drivers/net/wireless/iwlwifi/mvm/mvm.h | 13 +++++++++---- 2 files changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c index ac1cef6..3ce5831 100644 --- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c @@ -3189,14 +3189,18 @@ static int iwl_mvm_pre_channel_switch(struct ieee80211_hw *hw, break; case NL80211_IFTYPE_STATION: - apply_time = chsw->timestamp + - (vif->bss_conf.beacon_int * chsw->count * 1024); + /* Schedule the time event to a bit before beacon 1, + * to make sure we're in the new channel when the + * GO/AP arrives. + */ + apply_time = chsw->device_timestamp + + ((vif->bss_conf.beacon_int * (chsw->count - 1) - + IWL_MVM_CHANNEL_SWITCH_TIME_CLIENT) * 1024); if (chsw->block_tx) iwl_mvm_csa_client_absent(mvm, vif); - iwl_mvm_schedule_csa_period(mvm, vif, - IWL_MVM_CHANNEL_SWITCH_TIME_CLIENT, + iwl_mvm_schedule_csa_period(mvm, vif, vif->bss_conf.beacon_int, apply_time); break; default: diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h index 2816c6b..99a2590 100644 --- a/drivers/net/wireless/iwlwifi/mvm/mvm.h +++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h @@ -87,12 +87,17 @@ /* A TimeUnit is 1024 microsecond */ #define MSEC_TO_TU(_msec) (_msec*1000/1024) -/* These values represent the number of TUs before CSA "beacon 0" TBTT - * when the CSA time-event needs to be scheduled to start. They must - * be big enough to ensure that we switch in time. +/* For GO, this value represents the number of TUs before CSA "beacon + * 0" TBTT when the CSA time-event needs to be scheduled to start. It + * must be big enough to ensure that we switch in time. */ #define IWL_MVM_CHANNEL_SWITCH_TIME_GO 40 -#define IWL_MVM_CHANNEL_SWITCH_TIME_CLIENT 110 + +/* For client, this value represents the number of TUs before CSA + * "beacon 1" TBTT, instead. This is because we don't know when the + * GO/AP will be in the new channel, so we switch early enough. + */ +#define IWL_MVM_CHANNEL_SWITCH_TIME_CLIENT 10 /* * This value (in TUs) is used to fine tune the CSA NoA end time which should -- 1.9.1