What is the LensPosition in the hawkeye 64's metadata

I am trying to determine the focal length of my arducam 64 camera.
What is the value represented by LensPosition in the meta data returned by libcamera-still
Is it the distance between the sensor and the lens in mm or something else?

U can set the values from 1 to 13. If i remember correctly 1 is optical infinity ~ 9 metres. I remember seeing a mathematical formula how the other distances are calculated but cant find it atm. However u can measure the focus distances of other values in mm and plot them on a chart and derive the function this way.

here it is libcamera: libcamera::controls Namespace Reference