Scan fails to find wireless networks

Hi all,

I am having a bit of trouble getting my recent cvs version of the
at76c503 driver working with my `AIN Communication AWU2000P WLAN USB
Adapter' which I believe it should support.  The problem I am having is
with scanning for wireless networks, which does not appear to work at
all unless (rather stangely) I am already connected to an access point,
in which case it does what I would expect.

This occurs both with an x86 machine running linux 2.6.6 and
cross-compiling to an ARM machine running a patched 2.4.26 .

As a separate issue I am often experiencing complete lockups of my
machines on unplugging the wireless adapter, but for the moment I'm not
so concerned about that.

Here is a transcript of my attempts to get things working on the x86
box:

zebra:~# tail /var/log/kern.log
Oct  1 12:17:31 zebra kernel: usb 2-2.4: new full speed USB device using address 7
Oct  1 12:17:31 zebra kernel: /home/mp/cvs/at76c503a/at76_usbdfu.c: USB Device Firmware Upgrade (DFU)
handler v0.12beta19-static loading
Oct  1 12:17:31 zebra kernel: /home/mp/cvs/at76c503a/at76c503.c: Generic Atmel at76c503/at76c505
routines v0.12beta19-static
Oct  1 12:17:31 zebra kernel: /home/mp/cvs/at76c503a/at76c503-fw_skel.c: Atmel at76c505 (RFMD 2958)
Wireless LAN Driver v0.12beta19-static loading
Oct  1 12:17:31 zebra kernel: usbcore: registered new driver at76c505-rfmd2958
Oct  1 12:17:31 zebra kernel: /home/mp/cvs/at76c503a/at76c503-fw_skel.c: using compiled-in firmware
Oct  1 12:17:33 zebra kernel: /home/mp/cvs/at76c503a/at76c503.c: $Id: at76c503.c,v 1.69 2004/09/05
14:07:09 jal2 Exp $ compiled Sep 30 2004 11:31:05
Oct  1 12:17:33 zebra kernel: /home/mp/cvs/at76c503a/at76c503.c: firmware version 1.101.0 #86
(fcs_len 4)
Oct  1 12:17:33 zebra kernel: /home/mp/cvs/at76c503a/at76c503.c: device's MAC 00:0d:2f:01:72:fb,
regulatory domain MKK1 (Japan) (id 65)
Oct  1 12:17:33 zebra kernel: /home/mp/cvs/at76c503a/at76c503.c: registered wlan0
zebra:~# iwlist wlan0 scan
wlan0     No scan results
zebra:~# iwconfig wlan0 essid FD57
zebra:~# iwlist wlan0 scan
wlan0     No scan results
zebra:~# ifconfig wlan0 127.0.0.2
zebra:~# iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: 00:80:C8:37:FD:57
                    ESSID:"FD57"
                    Mode:Master
                    Channel:13
                    Encryption key:off
                    Quality:0/0  Signal level:43/255  Noise level:0/0
                    Bit Rate:1Mb/s
                    Bit Rate:2Mb/s
                    Bit Rate:5.5Mb/s
                    Bit Rate:11Mb/s
          Cell 02 - Address: 00:09:5B:58:7C:34
                    ESSID:"Spa ced ESSID"
                    Mode:Master
                    Channel:12
                    Encryption key:on
                    Quality:0/0  Signal level:34/255  Noise level:0/0
                    Bit Rate:1Mb/s
                    Bit Rate:2Mb/s
                    Bit Rate:5.5Mb/s
                    Bit Rate:11Mb/s

zebra:~#

Note that the scan only works after I have both connected to a known AP
and assigned myself an IP address.  This exact behaviour is occurring
repeatably on both my machines.  In addition, on the ARM machine I get a
couple of assertion failures after assigning the address:

# ifconfig wlan0 127.0.0.2
at76c503.c: at76c503.c:2905 assertion dev->istate == INIT failed
at76c503.c: at76c503.c:2876 assertion dev->istate == SCANNING failed
#

Anyone have any idea what is going on here, and what I might be able to
do to get around this problem?

Thanks a lot,
Mike