Can I use an external GPS receiver by connecting both GPS and Android device to a PC?

I have an HTC One X which I like and carry everywhere, but the GPS is atrocious. It takes tens of minutes to get a position, loses it easily and it's not even very accurate when it has a signal. However, I also have a Garmin GPS which is fantastic at gaining and holding a steady and accurate GPS location. I'd like to use the Garmin as an external GPS in combination with android's mock-location feature, in my car. It is definitely possible to drive gpsd on a pc with the garmin - but I don't know how to use that to provide location data to android. The phone is already rooted and I'm not averse to hacking it a bit more, but of course simpler solutions are preferred. Initially I would be happy plugging the Garmin and HTC into a laptop but I'll move to a Raspberry Pi as soon as I know it works. Not really bothered about using USB OTG to connect as this is for in-car use. So: Can I use gpsd running on a PC to control a mock-location on Android? If so, how?