Return-path: Received: from mail.atheros.com ([12.19.149.2]:57256 "EHLO mail.atheros.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750790Ab1BDGYH (ORCPT ); Fri, 4 Feb 2011 01:24:07 -0500 Received: from mail.atheros.com ([10.10.20.105]) by sidewinder.atheros.com for ; Thu, 03 Feb 2011 22:23:47 -0800 From: Vivek Natarajan To: CC: Subject: [PATCH 1/2] ath9k: Drain txq before sending a nullfunc frame. Date: Fri, 4 Feb 2011 11:53:59 +0530 Message-ID: <1296800640-6381-1-git-send-email-vnatarajan@atheros.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: In a highly noisy environment, a data frame which is queued before a nullfunc frame on a different hw queue may be sent over the air after the tx completion of nullfunc frame. This causes the station to enter power save and the AP to see the station as awake and continues to send the data traffic. Fix this by draining all tx queues before we send the null function frame with PM bit set. Signed-off-by: Vivek Natarajan --- drivers/net/wireless/ath/ath9k/xmit.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 68a1c76..0cb6017 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -1710,7 +1710,6 @@ static struct ath_buf *ath_tx_setup_buffer(struct ieee80211_hw *hw, bf->bf_buf_addr, txq->axq_qnum); - return bf; } @@ -1813,6 +1812,15 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb, if (unlikely(!bf)) return -ENOMEM; + if (ieee80211_is_nullfunc(hdr->frame_control) && + ieee80211_has_pm(hdr->frame_control)) { + /* Drain all the pending frames before we send a nullfunc frame + * to avoid any power save state mismatch between the station + * and the AP. + */ + ath_drain_all_txq(sc, false); + } + q = skb_get_queue_mapping(skb); spin_lock_bh(&txq->axq_lock); if (txq == sc->tx.txq_map[q] && -- 1.6.3.3