Multiple Ethernet Cards with Same network driver

Hi All,
I have written a ethernet driver on an embedded platform. If I need to
run same ethernet driver for multiple instances of hardware, how the
loading & unloading can be can be done ?

I understand that while calling the module_init(my_init) function, if a
call to alloc_etherdev() is made, kernel will assign ethernet device
names as "eth0", "eth1" in that sequence.

Since ethernet driver I have written is for an embedded application
where the base addresses of the devices and IRQ are fixed, while I
unload the driver, how can I find which one is being unloaded so that I
can free corresponding 'net_device' structure ? I see that there is no
parameter available for module_exit() function.

Any help/pointers greatly appreciated.

regards,
Keshav