Hi,
Cirrus Logic have released an update on their sources (https://github.com/CirrusLogic/rpi-linux/wiki/Building-the-code#install-the-kernel-modules-and-dtb-file-on-the-raspberry-pi) for the Raspberry Pi kernel.
For musicians trying to get the older Raspberry Pi boards (only A+ and B+) running in realtime mode like described here I provide an inofficial package for this kernel including all realtime patches. More info about this can be found on http://wiki.linuxaudio.org/wiki/raspberrypi.
The package contains a precompiled realtime kernel and the necessary libs/firmware files including the overlays provided by Cirrus Logic and can be downloaded here.
Instructions for installing the files can be found in the README.txt
This version of the kernel supports mmap which is needed for jack/jackd2 and a lot of other things to work.
A realtime example can be found here: https://blog.georgmill.de/2015/03/28/waveboard-with-arduino/
Have fun.
Yes, you are right. mmap support is working, so jack and jack2 are working right out of the box 🙂
I’ll add a comment about that in the article.
Thanks.
Thanks so much for this package!
You don’t explicitly say it on your blog post, but this kernel includes mmap support for the sound card (really, Cirrus should’ve included that right from the start – after all, the old kernel for the old Wolfson audio card included support for it out of the box). Which in turn allows dmix and dsnoop alsa plugins to work (and I guess it’s also needed for Jack, but haven’t tested that).
You literally saved my day.