From: Sven Eckelmann <sven.eckelmann@xxxxxxxxxxxx> The QCA4019 hw1.0 firmware 10.4-3.2.1-00050 and 10.4-3.5.3-00053 (and most likely all other) seem to ignore the WMI_CHAN_FLAG_DFS flag during the scan. This results in transmission (probe requests) on channels which are not "available" for transmissions. Since the firmware is closed source and nothing can be done from our side to fix the problem in it, the driver has to work around this problem. The WMI_CHAN_FLAG_PASSIVE seems to be interpreted by the firmware to not scan actively on a channel unless an AP was detected on it. Simple probe requests will then be transmitted by the STA on the channel. ath10k must therefore also use this flag when it queues a radar channel for scanning. This should reduce the chance of an active scan when the channel might be "unusable" for transmissions. Fixes: e8a50f8ba44b ("ath10k: introduce DFS implementation") Signed-off-by: Sven Eckelmann <sven.eckelmann@xxxxxxxxxxxx> --- Cc: Simon Wunderlich <simon.wunderlich@xxxxxxxxxxxx> Cc: Marek Puzyniak <marek.puzyniak@xxxxxxxxx> --- drivers/net/wireless/ath/ath10k/mac.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index 95243b48a179..76e9c6eaa051 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -3085,6 +3085,13 @@ static int ath10k_update_channel_list(struct ath10k *ar) passive = channel->flags & IEEE80211_CHAN_NO_IR; ch->passive = passive; + /* the firmware is ignoring the "radar" flag of the + * channel and is scanning actively using Probe Requests + * on "Radar detection"/DFS channels which are not + * marked as "available" + */ + ch->passive |= ch->chan_radar; + ch->freq = channel->center_freq; ch->band_center_freq1 = channel->center_freq; ch->min_power = 0; -- 2.11.0