Exibindo apenas redes Wi-Fi com o canal 11 (ralink)

Question

Estou usando um dongle wi-fi ODroid (chipset MediaTek (Ralink) RT5572N) em uma placa ARM jetston TK1. O dongle funciona bem em outras máquinas, mas no jetson, por alguma razão estranha, ele só mostra (e se conecta a) redes wifi no canal 11 e nada mais.

iwlist / nmcli / wifi-radar exibe somente as redes do canal 11, embora existam outras redes strongs em canais cada vez mais baixos.

Ubuntu 14.04.1 LTS, uname:

Linux tegra-ubuntu 3.10.40-grinch-21.3.4 #1 SMP PREEMPT Fri May 1 10:41:09 UTC 2015 armv7l armv7l armv7l GNU/Linux

saída dmesg:

[ 5522.348831] usb 2-1.2: new high-speed USB device number 31 using tegra-ehci
[ 5522.405935] usb 2-1.2: New USB device found, idVendor=148f, idProduct=5572
[ 5522.406154] usb 2-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 5522.411722] usb 2-1.2: Product: 802.11 n WLAN
[ 5522.411816] usb 2-1.2: Manufacturer: Ralink
[ 5522.411886] usb 2-1.2: SerialNumber: 1.0
[ 5522.509661] usb 2-1.2: reset high-speed USB device number 31 using tegra-ehci
[ 5522.553574] ieee80211 phy2: rt2x00_set_rt: Info - RT chipset 5592, rev 0222 detected
[ 5522.607281] ieee80211 phy2: rt2x00_set_rf: Info - RF chipset 000f detected
[ 5522.610789] ieee80211 phy2: Selected rate control algorithm 'minstrel_ht'
[ 5522.828157] ieee80211 phy2: rt2x00lib_request_firmware: Info - Loading firmware file 'rt2870.bin'
[ 5522.829747] ieee80211 phy2: rt2x00lib_request_firmware: Info - Firmware detected - version: 0.29

lsusb:

Bus 002 Device 031: ID 148f:5572 Ralink Technology, Corp. RT5572 Wireless Adapter

iw reg get:

country 00:
    (2402 - 2472 @ 40), (3, 20)
    (2457 - 2482 @ 40), (3, 20), PASSIVE-SCAN, NO-IBSS
    (2474 - 2494 @ 20), (3, 20), NO-OFDM, PASSIVE-SCAN, NO-IBSS
    (5170 - 5250 @ 40), (3, 20), PASSIVE-SCAN, NO-IBSS
    (5735 - 5835 @ 40), (3, 20), PASSIVE-SCAN, NO-IBSS

Lista de canais

$ iwlist wlan0 chan
wlan0     29 channels in total; available frequencies :
          Channel 01 : 2.412 GHz
          Channel 02 : 2.417 GHz
          Channel 03 : 2.422 GHz
          Channel 04 : 2.427 GHz
          Channel 05 : 2.432 GHz
          Channel 06 : 2.437 GHz
          Channel 07 : 2.442 GHz
          Channel 08 : 2.447 GHz
          Channel 09 : 2.452 GHz
          Channel 10 : 2.457 GHz
          Channel 11 : 2.462 GHz
          Channel 12 : 2.467 GHz
          Channel 13 : 2.472 GHz
          Channel 14 : 2.484 GHz
          Channel 36 : 5.18 GHz
          Channel 38 : 5.19 GHz
          Channel 40 : 5.2 GHz
          Channel 42 : 5.21 GHz
          Channel 44 : 5.22 GHz
          Channel 46 : 5.23 GHz
          Channel 48 : 5.24 GHz
          Channel 149 : 5.745 GHz
          Channel 151 : 5.755 GHz
          Channel 153 : 5.765 GHz
          Channel 155 : 5.775 GHz
          Channel 157 : 5.785 GHz
          Channel 159 : 5.795 GHz
          Channel 161 : 5.805 GHz
          Channel 165 : 5.825 GHz

Atualização: notei que a primeira vez que eu executo uma varredura em uma inicialização recente, ela mostra todas as redes. A digitalização depois disso mostra muito esporadicamente todos os resultados e, depois, nada mais.

Adicionada seção de saída / var / log / syslog abaixo, mas não tenho certeza de onde procurar por logs.

Dec  6 23:17:41 tegra-ubuntu dbus[300]: [system] Successfully activated service 'fi.w1.wpa_supplicant1'
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> wpa_supplicant started
Dec  6 23:17:41 tegra-ubuntu wpa_supplicant[2461]: Successfully initialized wpa_supplicant
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> (wlan0) supports 4 scan SSIDs
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <warn> Trying to remove a non-existant call id.
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> (wlan0): supplicant interface state: starting -> ready
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> (wlan0): device state change: unavailable -> disconnected (reason 'supplicant-available') [20 30 42]
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> (wlan0): supplicant interface state: ready -> disconnected
Dec  6 23:17:41 tegra-ubuntu NetworkManager[740]: <info> (wlan0) supports 4 scan SSIDs
Dec  6 23:17:41 tegra-ubuntu wpa_supplicant[2462]: wlan0: CTRL-EVENT-SCAN-STARTED 
Dec  6 23:17:43 tegra-ubuntu ModemManager[630]: <warn>  Couldn't find support for device at '/sys/devices/platform/tegra-ehci.2/usb2/2-1': not supported by any plugin
Dec  6 23:17:46 tegra-ubuntu NetworkManager[740]: <info> (wlan0): supplicant interface state: disconnected -> inactive

    

Answer 1

Acabou por desistir e comprou uma placa PCI mini Intel 7260. Isso funciona ...