No scan results for iwlist with Marvell libertas 8686 WLAN-BT combo module on OMAP3
 

Hi all,

I am in the process of enabling WLAN for a target board. It has a WLAN Bluetooth (WLAN-BT) combo module SP-W8ME-A from MuRata which has a Marvell WLAN (88W8686) + CSR Bluetooth chipset.

The target runs on OMAP3 with WLAN brought up using the following setup,

Driver: Marvell libertas 8686 WLAN Driver
Firmware Version: fw 9.70.3p14
Linux Kernel Version: 2.6.22.18

With the above setup I am able to:

1) insmod libertas driver.

2) Load the firmware successfully (by the driver).

3) 'iwconfig' command shows me the following:

eth1 IEEE 802.11b/g ESSID:"TEST"
Mode:Ad-Hoc Frequency:2.412 GHz Cell: 02:2A:4A:33:DB:BE
Bit Rate:0 kb/s Tx-Power=13 dBm
Retry limit:8 RTS thr=2347 B Fragment thr=2346 B
Encryption key:off
Power Management:off
Link Quality=76/100 Signal level=0 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:34471 Rx invalid frag:0
Tx excessive retries:66 Invalid misc:16830 Missed beacon:0

4) 'ifconfig' shows me that the interface is setup fine too.

eth1 Link encap:Ethernet HWaddr 00:21:E8:13:F4:A2
inet addr:192.168.101.50 Bcast:192.168.101.255 Mask:255.255.255.0
UP BROADCAST RUNNING 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)

Now I want to scan for networks, here I get into trouble.

5) 'iwlist' eth1 scan tells me 'No scan results'

I have setup test access points, so I am sure of getting at least one result.

I have tried scanning in both Managed and AdHoc mode and also on different channels.

My target always gives me a login shell with root access by default.
(So sudo is not required for iwlist as expected by some systems.)

The following are my concerns/queries:

a) What might be the possible cause of getting no results?

b) Is it that the libertas driver will not work for WLAN-BT modules?
(Scan works fine on other WLAN (8686) module without Bluetooth, so wireless tools seems to work fine.)

c) Can Bluetooth co-existence cause any problem?

d) I could also see a lot of 'Rx invalid crypt' and 'Invalid misc' packets. What could be wrong?


Please help me fix this issue. (Post queries if you require any further clarification on the setup)


Thanks in Advance

Ruchi