The problem is not that the makers aren't writing drivers. Linux devs write their own drivers all the time. The problem is that Dell chose a model that encrypts its communication, making it impossible for anyone but the maker to write a driver.

I have to disagree.   If it was easy then there should be a USB fingerprint reader device that works with UBUNTU or Redhat or SUSE out of the box.   I looked everywhere and I do not see any vendor selling devices like that let alone any vendors that specifically say they provide this feature in linux.  

sudo add-apt-repository ppa:fingerprint/fingerprint-gui
sudo apt-get update
sudo apt-get install libbsapi policykit-1-fingerprint-gui fingerprint-gui

doesn't actually help if there is no device to read the fingerprint.

https://askubuntu.com/questions/385372/vfs-495-finger-print-reader-not-working-in-ubuntu/924475#924475

https://www.amazon.com/s?k=fingerprint+scanner+USB+linux&i=electronics&ref=nb_sb_noss

If there is a model that works I would like to know what it is and who sells it.

I have to admit I don't understand why you want to use fingerprint readers.

They are considered highly insecure : as the CCC hackers have shown, it is very easy to fool all fingerprint readers (including those using infrared) with a few dollars of materials.

Fingerprints can very easily be grabbed, and faked. And with recent cameras, taking a picture of your hand is enough to extract your fingerprint and make a reverse-mold for it and within a few minutes unlock any machine protected with such devices.

The CCC and other hackers have published videos, pictures, howtos, software, complete manuals on how to do this.

And once your fingerprint is compromised, what will you do ? You cannot change them.

That's the main fallacy of biometrics: once compromised, you're screwed because you cannot change those.

It’s funny how 3 years after this thread was opened and a Dell official told us, that they will no longer sell their Ubuntu products with a useless fingerprint reader, they still do exactly this.

Last month I ordered a Precision 5540 with Ubuntu preinstalled and paid extra for a Fingerprint Reader. Unfortunately after I’ve got the notebook shipped I had to learn that the fingerprint reader isn’t working and that Dell sold me something absolutely useless without any hints before or during the purchase that this is the case. After I contacted Dell about this, they first replied that “I should install Windows” and after I told them that I obviously don’t want to do that they said “Ubuntu isn’t a Dell product, so I can’t help you”. I should contact the Linux support.

This is very frustrating, especially because Dell is aware of this issue since at least 3 years and they are still selling such products without any hints about the incompatibility.

The problem is manufacturers of such devices want them to be secure.

So they do it like Apple does : the fingerprint reader encrypts what it read, sends it to the operating system. And for Windows, they provide a C or C++ compiled DLL or binary that is able to decrypt the data and tell the OS OK or NOK

To give us a driver, it has to be either a firmware blob you cannot check (some distributions will not accept this) or give us sources, with the decrypting key. Once this key is known, then using that encryption becomes moot.

Two things come to mind.

First one, is that security through obscurity does NOT work. As military cryptographers have realized with many decades of experience (and seeing their hardware based crypto machines getting owned) this does not work. The key must carry the whole security. If your crypto device (or device protected by crypto) has part of its security requiring that you keep not only the key but also the cipher or mecanism secret, they you are failing. This is famously known as the Kerkoff's principle. More details @ Wikipedia here : https://en.wikipedia.org/wiki/Security_through_obscurity

But I understand the need to secure, on the hardware part, what comes out from the reader, to what gets parsed by the driver. But since the driver can be decompiled... Well.

Second, Dell might have its hands tied here. They buy the fingerprint component, but they have to sign a contract where they agree to protect the reader security but making sure they do not put out anything that might reduce its security. Which means not releasing a Linux driver whose sources would contain that key.

The only way left is the black hat way I am afraid. That is, find the Windows driver, desassemble and break it, and produce an open source driver for the reader. This might not be a very legal way of doing things, according to your country laws. And Dell will never endorse anything illegal like this, of course.

Looks like vfs7552 finally got added to libfprint.

https://gitlab.freedesktop.org/libfprint/libfprint/-/blob/master/NEWS

2021-06-30: v1.92.0 release

New drivers:
* vfs7552
* nb1010
* elanspi

After many many years that are really great news!. The problem is that I see debian/ubuntu libfprint packages are a bit outdated https://packages.debian.org/search?keywords=libfprint&searchon=names&suite=all&section=all

Let's hope that they package version 1.92.0 or version 1.94.0 soon.

I will probably contact maintainers if this would be possible to be done soon

Good news. Almost four years after this post was opened it can be said that our figerprint is finally supported:

​​ID 138a:0091 Validity Sensors, Inc. VFS7552 Touch Fingerprint Sensor

 libfprint-2-2 version 1.94.1-1 has been released in debian sid https://packages.debian.org/search?keywords=libfprint&searchon=names&suite=all§ion=all

I have installed it and now gnome recognize it:

I have to say that when you scan your finger it is not just to put it in the sensor. In my case when scaning it you have to swipe down the finger several times. The same when you loging swipe your finger from up to down.

Enjoy it

Hi - I am a linux novice and have adopted an Ubuntu variant called Zorin OS and this probe from my machine / database has indicated no success has ever been had for this fingerprint sensor. However looks like you have managed to get it working on Debian. Any help you can provide in getting things working for me? (have cross posted here)

@gonzalomarcote​  Thanks a lot! After wasting almost 4-5 hours on the web and trying different things i lost hope. But when i saw your comment and followed it. It just worked. Two phrases in your comment 'not just to put it in the sensor' and 'swipe down the finger several times' saved me. Thank you again.