Help writing a DVB driver for OS X
I'm looking at options to access DVB data on OS X. Initially I want to support the EyeTV DTT USB device, but in the long-run I'd like to support a number of popular devices. The problem I have is that there is no standard way of controlling such devices.
All the applications I know of that use them either hide the driver code within the application (for example EyeTV itself, all it's drivers are implemented totally in userspace and are not accessibl开发者_如何学Goe to external apps), or they use the seemingly defunkt MMInputFamily driver (no source code availible any more, author gone walkabouts).
I've done some research and found that a number of the devices I want to support are supported within the Linux DVB project. Further research indicates that some years ago there was an attempt to abstract the linux implementation so that it could potentially be recompiled on other platforms. The idea being that efforts to support devices should be pooled and the best way to do that would be to make the current open source implementation work on multiple platforms: it seems in the end to have amounted to little however.
The idea of compiling linux drivers against other *nix type platforms has also been taken up elsewhere with some success. The approach the author took is detailed on the page I linked, it seems potentially viable on OS X as well.
At any rate, there seem to be a number of options, but no clear winner:
- Find the source code for the MMInputFamily driver, try to get it working on OS X 10.6 and add support for the devices I require, referrencing the linux source code for pointers. Problem: the source code is nowhere to be found, nor is the author. Additionally it seems the author might perhaps have gone down another route had he fully appreciated the previous efforts to port the linux drivers to OS X.
- Attempt to port the linux drivers to OS X in a manner similar to the FreeBSD project I linked. Problem: this is very low-level work and work in this layer is not recommended by Apple if it can be avoided.
- Write a driver with OS X's IOKit: this is the preferred method for implementing drivers but I would have to do everything from scratch, clearly not a small job.
If I could I would really like to use the Linux source code, but I'm unsure if such a thing is really viable. Does anyone have any advice or ideas on the best way to proceed with this task?
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