[  128.375244] ehci_irq: port change detect
<6>usb 2-1: new high-speed USB device number 4 using sw-ehci
[  128.667068] usb 2-1: new high-speed USB device number 4 using sw-ehci
<6>usb 2-1: ath9k_htc: Firmware htc_9271.fw requested
[  128.846174] usb 2-1: ath9k_htc: Firmware htc_9271.fw requested
<6>usb 2-1: ath9k_htc: Transferred FW: htc_9271.fw, size: 50980
[  129.140509] usb 2-1: ath9k_htc: Transferred FW: htc_9271.fw, size: 50980
<6>ath9k_htc 2-1:1.0: ath9k_htc: HTC initialized with 33 credits
[  129.378582] ath9k_htc 2-1:1.0: ath9k_htc: HTC initialized with 33 credits
<6>ath9k_htc 2-1:1.0: ath9k_htc: FW Version: 1.3
[  129.602208] ath9k_htc 2-1:1.0: ath9k_htc: FW Version: 1.3
<7>ath: EEPROM regdomain: 0x809c
[  129.610591] ath: EEPROM regdomain: 0x809c
<7>ath: EEPROM indicates we should expect a country code
[  129.619636] ath: EEPROM indicates we should expect a country code
<7>ath: doing EEPROM country->regdmn map search
[  129.630001] ath: doing EEPROM country->regdmn map search
<7>ath: country maps to regdmn code: 0x52
[  129.639063] ath: country maps to regdmn code: 0x52
<7>ath: Country alpha2 being used: CN
[  129.647249] ath: Country alpha2 being used: CN
<7>ath: Regpair used: 0x52
[  129.654134] ath: Regpair used: 0x52
<6>ieee80211 phy2: Atheros AR9271 Rev:1
[  129.668453] ieee80211 phy2: Atheros AR9271 Rev:1
<7>Registered led device: ath9k_htc-phy2
[  129.681649] Registered led device: ath9k_htc-phy2
<30>udev[523]: renamed network interface wlan0 to wlan2
[  129.757306] udev[523]: renamed network interface wlan0 to wlan2
<6>ADDRCONF(NETDEV_UP): wlan2: link is not ready
[  129.939032] ADDRCONF(NETDEV_UP): wlan2: link is not ready

$ iwlist wlan2 scan
wlan2     No scan results