[pulseaudio-discuss] ACLs for USB devices on Debian GNU/Linux Squeeze/testing

[Frode Severin Hatlevik]

2010/8/8 Frode Severin Hatlevik <frodeseverin at gmail.com>:
> First of all, I will like to say thank you for a great piece of
> software. PulseAudio makes sound a mor pleasant experinence.
>
> Now to my problem. It is not with PA itself, but rather a matter of
> setting up my system to make things work. I have several USB devices;
> all from Logitech, incidently; that I want to use with my laptop. I am
> using Debian GNU/Linux Squeeze/testing on an i686 kernel.
>
> Before using PA I had my users in the "audio" group. After using PA
> for a while I removed all users from the "audio" group, and this
> solved all issues with user switching. I will try to reflect this in
> the Debian Wiki after successfully sorting out my present issue. The
> Debian wiki page for sound seems rather dated; it does not mention PA
> at all.
>
> After purging users from the "audio" group I am no longer able to use
> my USB sound devices; nether my headset nor the mic on my webcam works
> anymore, they simlly disappeared form the PA subsystem. The devices
> worked befor the purge. I have been advised that this is due to the
> lack of ACLs for the device nodes in /dev/snd, but I am at a loss in
> how to set this up in Debian. I understand that configuring the
> devicenodes is a task for the hotplug system together with udev and
> ConsoleKit, but I have little experience with setting theese up.
>
<snip />

I have now figured this one out for myself. It turned out to be quite
simple. I only needed to add a file, say 60-sound.rules containing the
following line:
SUBSYSTEM=="sound", ENV{ACL_MANAGE}="1"

Then I issued "udevadm trigger" and things started working.

It is important to note that this rule should be numbered below 70, as
the standard udev rule dealing with ACL is
/lib/udev/rules.d/70-acl.rules
at least on my Debian Squeeze/testing. Thus the matching needs to be
done prior to the execution of this rule.

I will file this as a bug in Debian BTS. Should this udev-trick be
included in the guide for packaging PA?

;)Frode
-- 
Da sa Gud: "Det bli lys!"
Og det ble lys.
                      1. Mosebok 1.3

And God said, "Let there be light,"
and there was light.
                      Genesis 1:3, NIV