How to get the data format for RawInput of each controller?

Is there an official source where I can find the exact data format of each controller from the manufacturer?
I am now trying to take the data of an xbox one controller using RawInput api and WM_INPUT message approach, but there is no guidance that I know of for the bRawData array of HID whatsoever!

I need to know which element of the array corresponds to which button/axis, and bitmasks for buttons as well.

For xbox one, and for all major controller manufacturers as well. That’s because I am trying to get input manually for a long story.