The hardware is not lacking.

But is isn't the proximity sensor but the ambient light sensor.

It is specialized on natural light AND infrared light.
There is an algorithm that mixes all different sorts of light and outputs only two key values.

If we can access to this algorithm, we can extract infrared values in a broad spectrum.

But no suitable driver exists.

(In fact we have to do the inverse calculation of the custom use. The sensor has two photodiodes. The second one is only about infrared to calculate the effect of infrared light on the first sensor to eliminate infrared influence on the value of the first. The custom goal is to have only the value of visible light.

We have to do the inverse: We calculate only the value of infrared light and eliminate the influence of visible light.)