[SOLVED] FIX for Linksys AE1200

[another_sapiens]

The device is a Linksys AE1200, and USB databases list it as 13b1:0039 – as you can see here: https://usb-ids.gowdy.us/read/UD/13b1/0039

The problem is that, when you reboot the PC, 13b1:0039 gets recognized as 13b1:0bdc, which prevents it from loading the brcmfmac kernel module... Because "0bdc" is not a real product. A tedious workaround was to physically unplug and replug it, since it gets identified as "0039" the second time (you can confirm this by running

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lsusb

before & after replugging).

After lots of troubleshooting, I found an automated way of doing this, without touching anything. The answer is based off of shodanex's reply to a similar issue: https://stackoverflow.com/q/442833

It involves explicitly telling the drivers to also be used with the device's incorrect ID.


# Steps to fix

Press Ctrl+Alt+T, or open your favorite terminal.
All the following commands must be run as sudo, but I got "permission denied" when running it as-is. So, run

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sudo -i

before anything. (if you get a prompt that says `#` instead of the regular `$`, you're all set)

Because brcmfmac might not even be loaded, you may need to load it yourself. So type:

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modprobe brcmfmac

Now for the actual fix, let's tell brcmfmac to also use this wrong ID:

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echo 13b1 0bdc > /sys/bus/usb/drivers/brcmfmac/new_id

This will make sure the device uses the brcmfmac module, even if its ID is incorrect. After a few seconds, the dongle should be recognized, allowing you to configure a WiFi network! You can do that through the GUI as usual or run

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nmtui

on another terminal if you have it installed.

If everything went well, you should have a working internet connection


Now that we know it works, we can automate this by running a cronjob every time the system boots.

Run:

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crontab -e

as superuser (which you should be, if you followed the steps), and you'll be shown an editor with an empty file. Paste the commands that fixed the issue in there (on different lines) and add "@reboot" at the start of both, like so:

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@reboot modprobe brcmfmac
@reboot echo 13b1 0bdc > /sys/bus/usb/drivers/brcmfmac/new_id

This tells the system to run those commands (as `sudo`) every time you boot it. In case your distro doesn't support it, you can search for other methods.

## More info

I tried a lot of things before coming up with this, and was about to give up on the issue. Luckily, someone else seems to have reported it: https://bugs.debian.org/cgi-bin/bugrepo ... ug=1001189

Of course, it's not a bug from Debian, as other distros have the same issue. It should be the kernel, but don't know if it's been reported upstream yet.

I hope this helps!