Why can a hardware item work in one kernel and not in another

puttingau · 07-28-2009, 09:50 AM

Hello,
I compiled a driver for my af9015 based Leadtek usb dtv dongle in Ubuntu Hardy, (kernel 2.6.24.19) and it worked well. I did the same with puppylinux 4.2 (kernel 2.6.25.16), and dmesg shows that the device is loaded and ready to go, identical to that in ubuntu, but it will not work.
What reasons are there that a module can compile correctly using different kernel sources, yet the device will not work, and are there any solutions?
Thanks

MS3FGX · 07-29-2009, 08:07 PM

A lot things change in the kernel from release to release, and if you are working with cutting-edge or in-development drivers it is entirely possible that a kernel upgrade (or downgrade) can break some functionality. Does the driver documentation mention anything about kernel compatibility?

puttingau · 08-02-2009, 07:53 AM

Thanks for replying. No, I can't see anything about kernel compatibility. What does one do? Wait until the distro comes out with a new kernel, or go back to an old one in which the device works? Or are there other options?