From patchwork Fri Apr 30 23:00:02 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Reinette Chatre X-Patchwork-Id: 96097 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o3UN0KpT024481 for ; Fri, 30 Apr 2010 23:00:20 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757300Ab0D3XAS (ORCPT ); Fri, 30 Apr 2010 19:00:18 -0400 Received: from mga02.intel.com ([134.134.136.20]:37185 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757075Ab0D3XAQ (ORCPT ); Fri, 30 Apr 2010 19:00:16 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP; 30 Apr 2010 15:58:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.52,305,1270450800"; d="scan'208";a="514112454" Received: from rchatre-desk.amr.corp.intel.com.jf.intel.com (HELO localhost.localdomain) ([134.134.15.94]) by orsmga002.jf.intel.com with ESMTP; 30 Apr 2010 15:59:46 -0700 From: Reinette Chatre To: linville@tuxdriver.com Cc: linux-wireless@vger.kernel.org, ipw3945-devel@lists.sourceforge.net, Johannes Berg , Reinette Chatre Subject: [PATCH wireless-2.6] iwlwifi: work around passive scan issue Date: Fri, 30 Apr 2010 16:00:02 -0700 Message-Id: <1272668402-3722-1-git-send-email-reinette.chatre@intel.com> X-Mailer: git-send-email 1.6.3.3 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 30 Apr 2010 23:00:20 +0000 (UTC) diff --git a/drivers/net/wireless/iwlwifi/iwl-commands.h b/drivers/net/wireless/iwlwifi/iwl-commands.h index 6383d9f..f4e59ae 100644 --- a/drivers/net/wireless/iwlwifi/iwl-commands.h +++ b/drivers/net/wireless/iwlwifi/iwl-commands.h @@ -2621,7 +2621,9 @@ struct iwl_ssid_ie { #define PROBE_OPTION_MAX_3945 4 #define PROBE_OPTION_MAX 20 #define TX_CMD_LIFE_TIME_INFINITE cpu_to_le32(0xFFFFFFFF) -#define IWL_GOOD_CRC_TH cpu_to_le16(1) +#define IWL_GOOD_CRC_TH_DISABLED 0 +#define IWL_GOOD_CRC_TH_DEFAULT cpu_to_le16(1) +#define IWL_GOOD_CRC_TH_NEVER cpu_to_le16(0xffff) #define IWL_MAX_SCAN_SIZE 1024 #define IWL_MAX_CMD_SIZE 4096 #define IWL_MAX_PROBE_REQUEST 200 diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c index 5062f4e..2367286 100644 --- a/drivers/net/wireless/iwlwifi/iwl-scan.c +++ b/drivers/net/wireless/iwlwifi/iwl-scan.c @@ -812,16 +812,29 @@ static void iwl_bg_request_scan(struct work_struct *data) rate = IWL_RATE_1M_PLCP; rate_flags = RATE_MCS_CCK_MSK; } - scan->good_CRC_th = 0; + scan->good_CRC_th = IWL_GOOD_CRC_TH_DISABLED; } else if (priv->scan_bands & BIT(IEEE80211_BAND_5GHZ)) { band = IEEE80211_BAND_5GHZ; rate = IWL_RATE_6M_PLCP; /* - * If active scaning is requested but a certain channel - * is marked passive, we can do active scanning if we - * detect transmissions. + * If active scanning is requested but a certain channel is + * marked passive, we can do active scanning if we detect + * transmissions. + * + * There is an issue with some firmware versions that triggers + * a sysassert on a "good CRC threshold" of zero (== disabled), + * on a radar channel even though this means that we should NOT + * send probes. + * + * The "good CRC threshold" is the number of frames that we + * need to receive during our dwell time on a channel before + * sending out probes -- setting this to a huge value will + * mean we never reach it, but at the same time work around + * the aforementioned issue. Thus use IWL_GOOD_CRC_TH_NEVER + * here instead of IWL_GOOD_CRC_TH_DISABLED. */ - scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH : 0; + scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT : + IWL_GOOD_CRC_TH_NEVER; /* Force use of chains B and C (0x6) for scan Rx for 4965 * Avoid A (0x1) because of its off-channel reception on A-band. diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c index e276f2a..2f47d93 100644 --- a/drivers/net/wireless/iwlwifi/iwl3945-base.c +++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c @@ -2966,7 +2966,8 @@ static void iwl3945_bg_request_scan(struct work_struct *data) * is marked passive, we can do active scanning if we * detect transmissions. */ - scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH : 0; + scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH_DEFAULT : + IWL_GOOD_CRC_TH_DISABLED; band = IEEE80211_BAND_5GHZ; } else { IWL_WARN(priv, "Invalid scan band count\n");