Using an Atheros 9271 WLAN USB card on Arch

szczurcio · 2016-06-22 10:07:36

I have a TP-Link TL-WN722N wireless USB adapter. This is the output of lsusb:

[user@t450s ~]$ lsusb
Bus 001 Device 002: ID 8087:8001 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 004: ID 5986:0366 Acer, Inc 
Bus 002 Device 003: ID 8087:0a2a Intel Corp. 
Bus 002 Device 002: ID 0cf3:9271 Atheros Communications, Inc. AR9271 802.11n
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Apparently, the ath9k(_htc) module that this card needs is in the kernel by default; lsmod seems to confirm this:

[user@t450s ~]$ lsmod | grep ath
ath9k_htc              65536  0
ath9k_common           32768  1 ath9k_htc
ath9k_hw              442368  2 ath9k_common,ath9k_htc
ath                    28672  3 ath9k_common,ath9k_htc,ath9k_hw
mac80211              655360  2 iwlmvm,ath9k_htc
cfg80211              495616  6 ath,iwlwifi,ath9k_common,mac80211,iwlmvm,ath9k_htc
led_class              16384  4 iwlmvm,thinkpad_acpi,ath9k_htc,input_leds
usbcore               200704  7 btusb,uvcvideo,ehci_hcd,ehci_pci,ath9k_htc,xhci_hcd,xhci_pci

The card is even visible as a wireless NIC:

[user@t450s ~]$ ip link list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 50:7b:9d:8c:51:b9 brd ff:ff:ff:ff:ff:ff
3: wlp3s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 18:5e:0f:90:55:29 brd ff:ff:ff:ff:ff:ff
4: wlp0s20u2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether f8:1a:67:1a:f2:a1 brd ff:ff:ff:ff:ff:ff

wlp3s0 is the built-in laptop NIC. These are the relevant lines from dmesg after I plug in the dongle:

[   67.154389] input: HDA Intel HDMI HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:03.0/sound/card0/input19
[   67.313701] ath9k_htc 2-2:1.0: ath9k_htc: HTC initialized with 33 credits
[   67.564805] psmouse serio1: synaptics: queried max coordinates: x [..5676], y [..4758]
[   67.577813] ath9k_htc 2-2:1.0: ath9k_htc: FW Version: 1.4
[   67.577814] ath9k_htc 2-2:1.0: FW RMW support: On
[   67.577815] ath: EEPROM regdomain: 0x809c
[   67.577816] ath: EEPROM indicates we should expect a country code
[   67.577816] ath: doing EEPROM country->regdmn map search
[   67.577817] ath: country maps to regdmn code: 0x52
[   67.577818] ath: Country alpha2 being used: CN
[   67.577818] ath: Regpair used: 0x52
[   67.582232] ieee80211 phy1: Atheros AR9271 Rev:1
[   67.583143] ath9k_htc 2-2:1.0 wlp0s20u2: renamed from wlan0

The card doesn't actually work, though. I cannot connect to my WiFi network using wpa_supplicant on that interface (it just sits there and hangs; the internal laptop card works perfectly), nor can I scan for networks nearby:

[user@t450s ~]$ sudo ip link set dev wlp0s20u2 up   // after I do this, the control LED on the card is turned on and stays on, doesn't blink or anything
[user@t450s ~]$ sudo iw dev wlp0s20u2 scan
[user@t450s ~]$  // no results

What can I do to get the card to work?

Last edited by szczurcio (2016-06-22 10:13:43)

Starfish · 2016-06-22 12:01:24

As

iw

does not print an error, I assume the signal is simply to weak. Have you tried doing the same with your laptop close to the router?

szczurcio · 2016-06-22 13:05:54

Starfish wrote:

As
iw
does not print an error, I assume the signal is simply to weak. Have you tried doing the same with your laptop close to the router?

Nope, as I said, the laptop's internal adapter doesn't have any issues connecting to my network or scanning (and in any case, the router is roughtly 3 meters away from me). It's not a signal problem.

Starfish · 2016-06-22 16:02:11

Okay, these are the last things I would try to do:
- scan via wifi-menu and then use netctl
- check "journalctl -xe" and see if some useful error messages occur
If that doesnt help either, I'm out...

Arch Linux

#1 2016-06-22 10:07:36

Using an Atheros 9271 WLAN USB card on Arch

#2 2016-06-22 12:01:24

Re: Using an Atheros 9271 WLAN USB card on Arch

#3 2016-06-22 13:05:54

Re: Using an Atheros 9271 WLAN USB card on Arch

#4 2016-06-22 16:02:11

Re: Using an Atheros 9271 WLAN USB card on Arch

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