Comment 33 for bug 1641290

The branch sbechet/libfprint is only a "first try"
the developer hasn't figured out yet how to make elan work.

At the moment the device is only added to be a "supported device" but the code on the file

https://github.com/sbechet/libfprint/blob/elan/libfprint/drivers/elan.c

throws an error (-71) on this method:

static void elan_cmd_cb(struct libusb_transfer *transfer)

on line 197 -> else if (transfer->length != transfer->actual_length) //throws the error -71

I'm reporting here the message from Igor Filatov to Sébastien Béchet

> With these devices the scanned area is so small that not many minutiae can
> be found there. I got like 5 o so with my finger and that's what I can
> visually confirm looking at the scanned images. It's not about image
> quality. I think original drivers could be using a different algorithm.
>
> Looks like your device doesn't react normally to 402a (not unexpected). It's
> the third init command in elan.h. Try removing it. Actually, you can try
> removing all commands not found in you traces. Just don't remove the arrays
> with commands for now, leave empty if needed.
>
> It doesn't seem to complicated to adapt the driver based on your traces but
> don't think I'll have any time for it soon…