[alsa-devel] 2.6.26.[6|7] vs. rt11 vs. alsa (usb) midi

[Takashi Iwai]

At Sat, 25 Oct 2008 19:46:27 -0700,
Fernando Lopez-Lezcano wrote:
> 
> Hi... anyone out there also having problem with this combination?
>    2.6.26.7 or 2.6.26.6 with 2.6.26.6-rt11 and alsa MIDI
> It looks to me like alsa midi is broken. 
> 
> Probably an interaction with the realtime kernel patch. A Fedora kernel
> based on 2.6.26.6 (2.6.26.6-49 on fc8) works fine, a very similarly
> patched kernel that includes the realtime patch does not. The
> configurations for both are almost the same (today I tried to change
> some of the most obvious differences and rebuild, with the same
> result). 
> 
> No problems with 2.6.24.7-rt21. 
> 
> Test: boot, login, plugin an external usb keyboard (Yamaha P250), it is
> recognized, use qjackctl alsa patchbay to connect it to kmidimon,
> kmidimon sees only _one_ midi message and that's it. Kmidimon can't be
> killed after that. 

What about other MIDI devices on other bus, e.g. an MPU401 on a PCI
soundcard or so?  There is a possibility of breakage in the USB driver
side, too.


Takashi