ACS Failure

[Nathan Royce]

config
*****
interface=wlan1
driver=nl80211
ssid=test
channel=0
*****

$ sudo hostapd test.conf
*****
Configuration file: test.conf
ACS: Automatic channel selection started, this may take a bit
wlan1: interface state UNINITIALIZED->ACS
wlan1: ACS-STARTED?
ACS: Unable to collect survey data
ACS: All study options have failed
Interface initialization failed
wlan1: interface state ACS->DISABLED
wlan1: AP-DISABLED?
ACS: Possibly channel configuration is invalid, please report this along with your config file.
ACS: Failed to start
wlan1: AP-DISABLED?
hostapd_free_hapd_data: Interface wlan1 wasn't started
nl80211: deinit ifname=wlan1 disabled_11b_rates=0
wlan1: interface state DISABLED->DISABLED
wlan1: interface state DISABLED->DISABLED
wlan1: AP-DISABLED?
hostapd_free_hapd_data: Interface wlan1 wasn't started
*****

driver: ath9k_htc
My understanding is that survey is not implemented, but I was curious about the following output from "event".

$ iw event
*****
wlan1 (phy #1): scan started
wlan1 (phy #1): scan finished: 2412 2417 2422 2427 2432 2437 2442 2447 2452 2457 2462,
(repeated 3 more times)
*****
With the scan happening, it makes me think maybe survey is implemented.
On the other hand, "$?iw dev wlan1 survey dump" doesn't output anything in "event".
It's like maybe hostapd is using a scan as a fallback.

Changing "channel=" to anything but auto (0) works.