USB无线网卡，无法搜索网络

我用TQ2440，用2.6.32.2移植了W541U网卡（RT2070）驱动，现在感觉网卡是已经驱动上了，但无法查找到网络，请问问题可能出在哪里？下面是现象：

[root@FwrTest /]# ifconfig
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:11 errors:0 dropped:0 overruns:0 frame:0
          TX packets:11 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1232 (1.2 KiB)  TX bytes:1232 (1.2 KiB)

wlan0     Link encap:Ethernet  HWaddr 00:E0:4C:A0:DD:53  
          inet addr:192.168.1.207  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)


[root@FwrTest /]# iwlist scanning
lo        Interface doesn't support scanning.

eth0      Interface doesn't support scanning.

wlan0     No scan results

补充，启动时的信息（我打开了debug）：

phy0 -> rt2x00lib_request_firmware: Info - Loading firmware file 'rt2870.bin'.
rt2800usb 1-1:1.0: firmware: requesting rt2870.bin
phy0 -> rt2x00lib_request_firmware: Info - Firmware detected - version: 0.29.
open device leds: No such file or directory

Please press Enter to activate this console. phy0 -> rt2x00mac_conf_tx: Info - Configured TX queue 0 - CWmin: 3, CWmax: 4, Aifs: 2, TXop: 102.
phy0 -> rt2x00mac_conf_tx: Info - Configured TX queue 1 - CWmin: 4, CWmax: 5, Aifs: 2, TXop: 188.
phy0 -> rt2x00mac_conf_tx: Info - Configured TX queue 2 - CWmin: 5, CWmax: 10, Aifs: 3, TXop: 0.
phy0 -> rt2x00mac_conf_tx: Info - Configured TX queue 3 - CWmin: 5, CWmax: 10, Aifs: 7, TXop: 0.