From 42c4568a4ace0adc27a9d6f02936e2047ba6fc7e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 11 Feb 2010 18:07:19 +0100 Subject: [PATCH] ath9k: add a workaround for ack timeout issues Adding support for setting the coverage class in some cases broke association and data transfer, as it overwrote the initial ACK timeout value from the initvals with a smaller value. I don't know why the new value works in 5 GHz (matches the initval there), but not in 2.4 GHz (initvals use 64us here), so until the problem is fully understood, the value should be increased again. Signed-off-by: Felix Fietkau Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/hw.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index f15fee76a4e2..f00f5c744f48 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1217,6 +1217,17 @@ void ath9k_hw_init_global_settings(struct ath_hw *ah) /* As defined by IEEE 802.11-2007 17.3.8.6 */ slottime = ah->slottime + 3 * ah->coverage_class; acktimeout = slottime + sifstime; + + /* + * Workaround for early ACK timeouts, add an offset to match the + * initval's 64us ack timeout value. + * This was initially only meant to work around an issue with delayed + * BA frames in some implementations, but it has been found to fix ACK + * timeout issues in other cases as well. + */ + if (conf->channel && conf->channel->band == IEEE80211_BAND_2GHZ) + acktimeout += 64 - sifstime - ah->slottime; + ath9k_hw_setslottime(ah, slottime); ath9k_hw_set_ack_timeout(ah, acktimeout); ath9k_hw_set_cts_timeout(ah, acktimeout); -- GitLab