EDIT: After further investigation it appears that HDStar is not supported on latest Linux kernels. It does appear to be working at first glance, but it doesn’t really work. We have a patch that can be applied to Linux kernel 4.x which makes HDStar work. Applying it to your system is something you’d have to research on your own, though.
Just a heads-up realted to soon-upcoming Intel (desktop Linux) version of ORx:
HDStar tuner is supported on desktop Linux distros, but only with Linux kernel 4.1 and later (tested with Ubuntu and Arch Linux with kernels 4.1 and 4.2 respectively). I haven’t tested on 4.0 but it may actually work.
If you are eager to try out the new Intel version, please be sure your tuner works with your desktop. Simple test is to plug it in and make sure
/dev/dvb/adapter0/frontend0 appears in your filesystem. Post here if you are having issues getting your tuner up and running.
As for other tuners, PCTV tuner should work with kernels 3.19.x and later, but you may need firmware files. Also, basically any well-behaved LinuxTV-API-compatible tuner should work. Check LinuxTV wiki which may give you information on where to find firmware files for your particular tuner and whether it is supported.