Re: [LAU] Many identical cards - how to keep them straight

On Sun Mar 09, 2008 at 07:24:00PM -0700, Mark Knecht wrote:
> On Sun, Mar 9, 2008 at 7:00 PM, David <dplist@email-addr-hidden> wrote:
> > On Sun, 9 Mar 2008 15:57:16 -0700
> > "Mark Knecht" <markknecht@email-addr-hidden> wrote:
> >
> > > On Sun, Mar 9, 2008 at 3:52 PM, drew Roberts <zotz@email-addr-hidden> wrote:
> > > >
> > > > On Sunday 09 March 2008 18:44:21 Mark Knecht wrote:
> > > > > Hi,
> > > > > I'm aware of and use standard Alsa methods to keep different
> > > > > sound cards in the same system straight as far as Alsa is
> > > > > concerned. I'm wondering what the proper process would be to
> > > > > keep 3 HDSP9652's which are physically in the same system, or
> > > > > multiple USB sound devices external to the system, straight as
> > > > > far as Alsa is concerned. I'd like to know that a certain card
> > > > > always will be always be card 0, card 1 or card 2. I do not want
> > > > > Alsa or Linux to make this decision for me and I certainly don't
> > > > > want Alsa to change them from boot cycle to boot cycle.
> > > > >
> > > > > What's the process to determine which identical card is
> > > > > which? Do you need to determine some sort of card specific
> > > > > hardware ID and then write udev rules or is there some way to do
> > > > > this within Alsa?
> > > >
> > > > I needed to solve this problem a while back. The best help I got
> > > > was telling me it was not possible.
> > >
> > > Humm, that's a pretty glaring disappointment, assuming it's true, and
> > > I have no reason to believe it isn't.
> > > >
> > > > I would be very interested to learn that there is a way. I got a
> > > > lot of info that would help with non-identical cards though.
> >
> > I have not tried this but maybe well crafted udev rules could help ?
> > The page http://reactivated.net/writing_udev_rules.html#sysfsmatch
> > gives hints about matching device names to data read from sysfs.
> >
> > Reading this doc, it looks like you might find info that uniquely
> > identify each of your cards using the command
> > "udevinfo -a -p $(udevinfo -q path -n /dev/snd/<yourdevice>)" and craft
> > you local rules from there.
> >
> > This might be a question worth asking on alsa-users too.
> >
> > HTH
> >
> > --
> > David
> >
>
> Yeah, as I said in the original post I suspected that if Alsa couldn't
> do it then udev might be the way to go. Unfortunately that might mean
> that every time I set up a new system I'd have to craft a file
> specifically for that system. I was hoping that maybe there was some
> way for Alsa to look at the card's ID and then automatically assign
> the cards in ID order, etc.

there is, alias snd-slot and snd-card stuff in modprobe conf in /etc (/etc/modules.d/alsa here). im not sure if it works if all the cards are using the same driver

keeps my internal on hw:1 so an Indigo is alwyas default anwyays..
_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@email-addr-hidden
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
Received on Mon Mar 10 08:15:03 2008