Subject: Re: dm9601 as ethX or usbX?

From: Peter Korsgaard <[email-masked]>
Date: Mon, 20 Apr 2009 18:07:58 +0200

>>>>> "Marcin" == Marcin Juszkiewicz <[email-masked]> writes:

Hi,

 Marcin> Is this normal behaviour of those adapters that ones with empty eeprom
 Marcin> ends as usbX?

Yes. The code in question is located in
drivers/net/usb/usbnet.c:usbnet_probe():

        strcpy (net->name, "usb%d");
...
                // heuristic:  "usb%d" for links we know are two-host,
                // else "eth%d" when there's reasonable doubt.  userspace
                // can rename the link if it knows better.
                if ((dev->driver_info->flags & FLAG_ETHER) != 0
                                && (net->dev_addr [0] & 0x02) == 0)
                        strcpy (net->name, "eth%d");

Bit 1 of the most significant byte of the MAC address specifies that
it's a locally generated (E.G. random) MAC address, which is what
dm9601.c will use if there's nothing specified in the EEPROM (or there
isn't any EEPROM connected).

 Marcin> I would prefer to have both as ethX as I use them in devices
 Marcin> where usbX as usually usb-gadget (g_ether) and as such usb0
 Marcin> is configured in total different scheme.

 Marcin> I know that one of options would be using udev and renaming
 Marcin> of interface but then I would have to remember to always copy
 Marcin> that rule to each device.

Sorry, other than that I don't know any other options (you could
ofcourse try to convince the usbnet maintainer to change the usbnet
logic, but it seems pretty sensible to me).

-- 
Bye, Peter Korsgaard