Red Hat Bugzilla – Bug 49629
(SOUND MPU401)Roland MPU 401 card not working with playmidi, etc.
Last modified: 2008-08-01 12:22:51 EDT
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Description of problem:
I have a genuine Roland MPU 401 external midi card (the old ISA one). It
has been working fine on previous versions of RedHat Linux. With RedHat
7.1, the card seems to work properly if I just cat /dev/sequencer >file
and cat file >/dev/sequencer, but any other software doesn't work.
Steps to Reproduce:
1. playmidi -e anymidifile.mid
Actual Results: Usually playmidi just hangs, but sometimes I get random
sounds out of the external midi keyboard.
Expected Results: Proper playback of the midi file.
I have similar problems with the jazz sequencer software (not included with
RedHat Linux), and other midi software that I have written.
sndconfig does not recognize the card, it uses my sound card as a midi
device. I manually changed /etc/modules.conf to my original settings for
alias synth0 mpu401
options -k mpu401 io=0x330 irq=7
Is this bug being investigated?
We don't have the hardware in question.
Is it a PnP card in any manner - does it show up in /proc/isapnp?
The card is not PnP. It is quite old, but it is the basis of the external midi
interface standard used by many other cards. Do you have any external midi
hardware to test with?
I found that this is not a bug in the mpu401 driver. It is a conflict between
the sb driver and the mpu401 driver. If I remove all sound related kernel
modules and then insmod mpu401, it works fine. I can't seem to get my
modules.conf to handle this properly. If I manually insmod mpu401 before any
other sound modules are loaded, then everything works fine. Apparently the sb
driver is preventing any other driver from servicing sound-service-0-3 even if
uart401 is disabled.
vacto: in answer to your previous question, no, we don't have external midi HW.
Since it appears to be a driver issue, assigning to the kernel.
I no longer have the MPU 401, so this bug is moot.
Thanks for the bug report. However, Red Hat no longer maintains this version of
the product. Please upgrade to the latest version and open a new bug if the problem
The Fedora Legacy project (http://fedoralegacy.org/) maintains some older releases,
and if you believe this bug is interesting to them, please report the problem in
the bug tracker at: http://bugzilla.fedora.us/