[PATCH 0/3] hostapd: introduce Automatic Channel Selection (ACS)

Sun Aug 25 02:39:53 EDT 2013

Andreas Hartmann wrote:
> Michal Kazior wrote:
>> Hi,
>>
>> This is an attempt at ressurecting ACS effort for hostapd.
>>
>> This is based on the work done by Luis R. Rodriguez
>> <lrodriguez at qca.qualcomm.com>.
> 
> I tested it, too with ath9k (AR9300). It's working pretty fine for me
> (at a first glance).

Well, the second glance shows a problem on boot up of the machine: I'm
always getting an error on channel 13 with the noise floor:

1377411942.774908: ACS: Survey is missing noise floor
1377411942.774913: ACS: Channel 13 has insufficient survey data

Restarting hostapd w/o unloading wireless modules stack "resolves" the
problem.

The complete log output on error:

1377411935.488850: ACS: Automatic channel selection started, this may take a bit
1377411935.488862: ACS: scanning 1 / 5
1377411935.488875: wlan1: nl80211: scan request
1377411935.491572: Scan requested (ret=0) - scan timeout 10 seconds
1377411935.491588: Interface initialization will be completed in a callback (ACS)
1377411935.491680: ctrl_iface not configured!
1377411935.493843: RTM_NEWLINK: operstate=0 ifi_flags=0x11043 ([UP][RUNNING][LOWER_UP])
1377411935.493887: RTM_NEWLINK, IFLA_IFNAME: Interface 'br0' added
1377411935.493917: wlan1: Event INTERFACE_STATUS (5) received
1377411935.493927: Unknown event 5
1377411935.493937: RTM_NEWLINK: operstate=0 ifi_flags=0x1002 ()
1377411935.493988: nl80211: Ignore interface down event since interface wlan1 is up
1377411935.493998: RTM_NEWLINK: operstate=0 ifi_flags=0x1043 ([UP][RUNNING])
1377411935.494006: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan1' added
1377411935.494020: nl80211: if_removed already cleared - ignore event
1377411935.494050: RTM_NEWLINK: operstate=0 ifi_flags=0x1043 ([UP][RUNNING])
1377411935.494059: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan1' added
1377411935.494072: nl80211: if_removed already cleared - ignore event
1377411935.494085: nl80211: Add ifindex 4 for bridge br0
1377411935.494094: nl80211: Add own interface ifindex 4
1377411935.494144: nl80211: Drv Event 33 (NL80211_CMD_TRIGGER_SCAN) received for wlan1
1377411935.494158: wlan1: nl80211: Scan trigger
1377411935.494176: nl80211: Drv Event 36 (NL80211_CMD_REG_CHANGE) received for wlan1
1377411935.494183: nl80211: Regulatory domain change
1377411935.494191: wlan1: Event CHANNEL_LIST_CHANGED (31) received
1377411935.494197: Unknown event 31
1377411936.206566: RTM_NEWLINK: operstate=0 ifi_flags=0x1003 ([UP])
1377411936.206619: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan1' added
1377411936.206657: nl80211: if_removed already cleared - ignore event
1377411936.206672: nl80211: Add ifindex 4 for bridge br0
1377411936.206679: nl80211: Add own interface ifindex 4
1377411936.206688: RTM_NEWLINK: operstate=0 ifi_flags=0x1003 ([UP])
1377411936.206695: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan1' added
1377411936.206708: nl80211: if_removed already cleared - ignore event
1377411936.934475: nl80211: Drv Event 34 (NL80211_CMD_NEW_SCAN_RESULTS) received for wlan1
1377411936.934521: wlan1: nl80211: New scan results available
1377411936.934547: wlan1: Event SCAN_RESULTS (3) received
1377411936.934557: ACS: using survey based algorithm (acs_num_scans=5)
1377411936.934685: nl80211: Freq survey dump event (freq=2412 MHz noise=-95 channel_time=119 busy_time=4 tx_time=0 rx_time=1 filled=001f)
1377411936.934708: nl80211: Freq survey dump event (freq=2417 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934720: nl80211: Freq survey dump event (freq=2422 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934730: nl80211: Freq survey dump event (freq=2427 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934741: nl80211: Freq survey dump event (freq=2432 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934750: nl80211: Freq survey dump event (freq=2437 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411936.934760: nl80211: Freq survey dump event (freq=2442 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934770: nl80211: Freq survey dump event (freq=2447 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934779: nl80211: Freq survey dump event (freq=2452 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934789: nl80211: Freq survey dump event (freq=2457 MHz noise=-86 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934798: nl80211: Freq survey dump event (freq=2462 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934807: nl80211: Freq survey dump event (freq=2467 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411936.934816: nl80211: Freq survey dump event (freq=2472 MHz noise=0 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001e)
1377411936.934825: nl80211: Freq survey dump event (freq=5180 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934835: nl80211: Freq survey dump event (freq=5200 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934846: nl80211: Freq survey dump event (freq=5220 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934855: nl80211: Freq survey dump event (freq=5240 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934864: nl80211: Freq survey dump event (freq=5260 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934872: nl80211: Freq survey dump event (freq=5280 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934894: nl80211: Freq survey dump event (freq=5300 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934904: nl80211: Freq survey dump event (freq=5320 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411936.934923: wlan1: Event SURVEY (56) received
1377411936.934932: ACS: scanning 2 / 5
1377411936.934961: wlan1: nl80211: scan request
1377411936.945733: Scan requested (ret=0) - scan timeout 30 seconds
1377411936.945767: nl80211: Drv Event 33 (NL80211_CMD_TRIGGER_SCAN) received for wlan1
1377411936.951309: wlan1: nl80211: Scan trigger
1377411938.394532: nl80211: Drv Event 34 (NL80211_CMD_NEW_SCAN_RESULTS) received for wlan1
1377411938.394582: wlan1: nl80211: New scan results available
1377411938.394597: wlan1: Event SCAN_RESULTS (3) received
1377411938.394604: ACS: using survey based algorithm (acs_num_scans=5)
1377411938.394675: nl80211: Freq survey dump event (freq=2412 MHz noise=-95 channel_time=240 busy_time=9 tx_time=0 rx_time=1 filled=001f)
1377411938.394691: nl80211: Freq survey dump event (freq=2417 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394702: nl80211: Freq survey dump event (freq=2422 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394713: nl80211: Freq survey dump event (freq=2427 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394724: nl80211: Freq survey dump event (freq=2432 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411938.394734: nl80211: Freq survey dump event (freq=2437 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394744: nl80211: Freq survey dump event (freq=2442 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394754: nl80211: Freq survey dump event (freq=2447 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394764: nl80211: Freq survey dump event (freq=2452 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394774: nl80211: Freq survey dump event (freq=2457 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394784: nl80211: Freq survey dump event (freq=2462 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394794: nl80211: Freq survey dump event (freq=2467 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394804: nl80211: Freq survey dump event (freq=2472 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411938.394814: nl80211: Freq survey dump event (freq=5180 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394824: nl80211: Freq survey dump event (freq=5200 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394833: nl80211: Freq survey dump event (freq=5220 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394842: nl80211: Freq survey dump event (freq=5240 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394852: nl80211: Freq survey dump event (freq=5260 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394861: nl80211: Freq survey dump event (freq=5280 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394870: nl80211: Freq survey dump event (freq=5300 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394879: nl80211: Freq survey dump event (freq=5320 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411938.394896: wlan1: Event SURVEY (56) received
1377411938.394906: ACS: scanning 3 / 5
1377411938.394919: wlan1: nl80211: scan request
1377411938.414982: Scan requested (ret=0) - scan timeout 30 seconds
1377411938.415113: nl80211: Drv Event 33 (NL80211_CMD_TRIGGER_SCAN) received for wlan1
1377411938.415127: wlan1: nl80211: Scan trigger
1377411939.857503: nl80211: Drv Event 34 (NL80211_CMD_NEW_SCAN_RESULTS) received for wlan1
1377411939.857537: wlan1: nl80211: New scan results available
1377411939.857549: wlan1: Event SCAN_RESULTS (3) received
1377411939.857556: ACS: using survey based algorithm (acs_num_scans=5)
1377411939.857618: nl80211: Freq survey dump event (freq=2412 MHz noise=-95 channel_time=363 busy_time=14 tx_time=0 rx_time=2 filled=001f)
1377411939.857632: nl80211: Freq survey dump event (freq=2417 MHz noise=-95 channel_time=110 busy_time=4 tx_time=0 rx_time=4 filled=001f)
1377411939.857643: nl80211: Freq survey dump event (freq=2422 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857653: nl80211: Freq survey dump event (freq=2427 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857663: nl80211: Freq survey dump event (freq=2432 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857673: nl80211: Freq survey dump event (freq=2437 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411939.857682: nl80211: Freq survey dump event (freq=2442 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857692: nl80211: Freq survey dump event (freq=2447 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857701: nl80211: Freq survey dump event (freq=2452 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857710: nl80211: Freq survey dump event (freq=2457 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857719: nl80211: Freq survey dump event (freq=2462 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857728: nl80211: Freq survey dump event (freq=2467 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857737: nl80211: Freq survey dump event (freq=2472 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411939.857746: nl80211: Freq survey dump event (freq=5180 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857756: nl80211: Freq survey dump event (freq=5200 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857765: nl80211: Freq survey dump event (freq=5220 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857774: nl80211: Freq survey dump event (freq=5240 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857782: nl80211: Freq survey dump event (freq=5260 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857791: nl80211: Freq survey dump event (freq=5280 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857800: nl80211: Freq survey dump event (freq=5300 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857808: nl80211: Freq survey dump event (freq=5320 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411939.857824: wlan1: Event SURVEY (56) received
1377411939.857833: ACS: scanning 4 / 5
1377411939.857841: wlan1: nl80211: scan request
1377411939.868570: Scan requested (ret=0) - scan timeout 30 seconds
1377411939.868580: nl80211: Drv Event 33 (NL80211_CMD_TRIGGER_SCAN) received for wlan1
1377411939.868584: wlan1: nl80211: Scan trigger
1377411941.320514: nl80211: Drv Event 34 (NL80211_CMD_NEW_SCAN_RESULTS) received for wlan1
1377411941.320551: wlan1: nl80211: New scan results available
1377411941.320565: wlan1: Event SCAN_RESULTS (3) received
1377411941.320572: ACS: using survey based algorithm (acs_num_scans=5)
1377411941.320641: nl80211: Freq survey dump event (freq=2412 MHz noise=-95 channel_time=478 busy_time=18 tx_time=0 rx_time=3 filled=001f)
1377411941.320656: nl80211: Freq survey dump event (freq=2417 MHz noise=-95 channel_time=110 busy_time=2 tx_time=0 rx_time=2 filled=001f)
1377411941.320666: nl80211: Freq survey dump event (freq=2422 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320691: nl80211: Freq survey dump event (freq=2427 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320702: nl80211: Freq survey dump event (freq=2432 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411941.320712: nl80211: Freq survey dump event (freq=2437 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411941.320722: nl80211: Freq survey dump event (freq=2442 MHz noise=-95 channel_time=119 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320732: nl80211: Freq survey dump event (freq=2447 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320741: nl80211: Freq survey dump event (freq=2452 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320758: nl80211: Freq survey dump event (freq=2457 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320768: nl80211: Freq survey dump event (freq=2462 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320778: nl80211: Freq survey dump event (freq=2467 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320787: nl80211: Freq survey dump event (freq=2472 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411941.320796: nl80211: Freq survey dump event (freq=5180 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320806: nl80211: Freq survey dump event (freq=5200 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320814: nl80211: Freq survey dump event (freq=5220 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320823: nl80211: Freq survey dump event (freq=5240 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320832: nl80211: Freq survey dump event (freq=5260 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320840: nl80211: Freq survey dump event (freq=5280 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320849: nl80211: Freq survey dump event (freq=5300 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320858: nl80211: Freq survey dump event (freq=5320 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411941.320874: wlan1: Event SURVEY (56) received
1377411941.320883: ACS: scanning 5 / 5
1377411941.320892: wlan1: nl80211: scan request
1377411941.331547: Scan requested (ret=0) - scan timeout 30 seconds
1377411941.331558: nl80211: Drv Event 33 (NL80211_CMD_TRIGGER_SCAN) received for wlan1
1377411941.331562: wlan1: nl80211: Scan trigger
1377411942.774526: nl80211: Drv Event 34 (NL80211_CMD_NEW_SCAN_RESULTS) received for wlan1
1377411942.774566: wlan1: nl80211: New scan results available
1377411942.774579: wlan1: Event SCAN_RESULTS (3) received
1377411942.774586: ACS: using survey based algorithm (acs_num_scans=5)
1377411942.774654: nl80211: Freq survey dump event (freq=2412 MHz noise=-95 channel_time=593 busy_time=20 tx_time=0 rx_time=3 filled=001f)
1377411942.774668: nl80211: Freq survey dump event (freq=2417 MHz noise=-95 channel_time=110 busy_time=2 tx_time=0 rx_time=2 filled=001f)
1377411942.774679: nl80211: Freq survey dump event (freq=2422 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774690: nl80211: Freq survey dump event (freq=2427 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774700: nl80211: Freq survey dump event (freq=2432 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411942.774710: nl80211: Freq survey dump event (freq=2437 MHz noise=-95 channel_time=110 busy_time=1 tx_time=0 rx_time=1 filled=001f)
1377411942.774719: nl80211: Freq survey dump event (freq=2442 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774745: nl80211: Freq survey dump event (freq=2447 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774756: nl80211: Freq survey dump event (freq=2452 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774766: nl80211: Freq survey dump event (freq=2457 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774775: nl80211: Freq survey dump event (freq=2462 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774785: nl80211: Freq survey dump event (freq=2467 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774794: nl80211: Freq survey dump event (freq=2472 MHz noise=-95 channel_time=110 busy_time=0 tx_time=0 rx_time=0 filled=001f)
1377411942.774803: nl80211: Freq survey dump event (freq=5180 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774813: nl80211: Freq survey dump event (freq=5200 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774822: nl80211: Freq survey dump event (freq=5220 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774830: nl80211: Freq survey dump event (freq=5240 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774848: nl80211: Freq survey dump event (freq=5260 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774857: nl80211: Freq survey dump event (freq=5280 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774866: nl80211: Freq survey dump event (freq=5300 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774874: nl80211: Freq survey dump event (freq=5320 MHz noise=0 channel_time=0 busy_time=0 tx_time=0 rx_time=0 filled=0000)
1377411942.774890: wlan1: Event SURVEY (56) received
1377411942.774900: ACS: Trying survey-based ACS
1377411942.774908: ACS: Survey is missing noise floor
1377411942.774913: ACS: Channel 13 has insufficient survey data
1377411942.774919: ACS: Surveys have insufficient data
1377411942.774924: ACS: All study options have failed
1377411942.774936: ACS: Failed to start

Thanks,
Andreas