However, for structural integrity related reasons, it might be necessary to put the mounts in the bottom two slots and have two additional modules in the top two slots that serve no electrical function and simply hold the mounting rails in place.
It will probably be necessary to offset the mounts upwards so that the laptop can be set down on its feet without putting its weight on the joy-con triggers.
Another idea I had was to offset the mounting rails away from the laptop slightly, and have a couple of paddles that hook into the rails that go under the controllers that can be pulled with the middle finger and ring finger to depress the SL and SR buttons while the joy-con is docked. This is functionality that the Switch itself lacks. Below I illustrated the approximate positions of these paddles with a couple of paperclips.
Rather than wrestle with Nintendo’s proprietary hardware and firmware, it might be easier to design controllers with a similar form factor that attaches as an expansion card or plugs into an expansion card (connecting over usb is way simpler and less hardware than bluetooth, plus you could power directly and wouldn’t need a battery). As long as you follow HID protocol, you won’t need any extra drivers and it would work on most if not all operating systems without installing new drivers.
Of course, this approach defeats the point of hacking the Nintendo joy-cons and requires more knowledge of circuit and firmware design, but it accomplishes the same result. The catch being you wouldn’t be able to use them with your switch (but you could use it with other laptops).
I was thinking about this the other day but not with the whole laptop only using the main board with a smallish screen like the 9.7" iPad Pro 2048x1536 IPS. And have the control integrated and overlapping the board.
Making a Switch/Steam Deck like device with the Framework.
I started looking into reverse engineering joycons for my pocket switch (my power is out or I’d post the CAD models)
And yes Frosty joycons work with both Windows/Linux. To get them to act like one controller requires a few extra steps but pairing them is just Bluetooth.