Quickest way to modify/reload existing Linux driver
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I am trying to understand an existing Linux Wi-Fi driver for a USB Wi-Fi adapter.  While I can read the C code, I would also like to be able to insert debug/print statements at certain critical spots in the driver to see how it behaves when executed.  On a Linux system, after modifying the driver code, how does one go about loading it into the kernel in such a way that it replaces the old driver?  Is there a way to "hotplug substitute" it straight over the old driver, or is it more complicated than that?

I intend on doing this inside of an expendible virtual machine, so I am not concerned about messing up the original driver, for what it counts.    