Clemens Ladisch wrote: > Jan 'RedBully' Seiffert wrote: >> After Gentoo switched to udev-coldplug, my two soundcards get randomly >> reordered on reboot. Now I need to write a udev rule to give them a >> persistent ordering, but failed to do so until now, partly because i >> don't know on what key ALSA orders devices so they become card0 and 1, >> hw0 and hw1, partly because this feature of udev is so new. > > ALSA's card ordering mechanism predates udev and isn't compatible with > it. > *sigh* ;( > The ALSA framework has its own internal card list (that is shown in > /proc/asound/cards). Drivers can be instructed to take a specific card > number with the 'index' option, and this is the only official way of > reordering cards. > I want to thank you and Marco for the clarification. After reading Marcos mail, i slabbed my forehead like: "Ahh, yes, the index option". Only saw it once on an old SuSE in the conf-files on the PC of my brother. I now solved the problem for me with: options snd-ice1712 index=0 options snd-via82xx index=1 in /etc/modules.d/alsa (which then migrates to the automatic generated /etc/modprobe.conf, on gentoo). Now, after several reboots, it seems to work, also with udev-coldplug (which is tricky, because it happens so early, even before module autoload). > It is, in theory, possible to rename the device files, but you have to > be aware that > 1) all devices files of one card must be renamed consistently, i.e, > the card number in the controlC*/hwdepC*D*/rawmidiC*D*/pcmC*D*p/ > pcmC*D*c files (the number after the "C") must be the same for all > device files belonging to each card; and > 2) enumerating cards will no longer work correctly (the card number > returned by ALSA will still be the number specified with the index > parameter), i.e., card names/descriptions will be wrong when a > program tries to show them. > > Renaming the device files in a consistent manner shouldn't be the problem. Sure, the udev-rules would get a little bit longer, but still possible (or call out to a program which gives the right name back). But why should i do it, if it does not influence ALSA (the expected way), only confuses it? And the main target, getting a persistent 'hw0' etc. and 'default' isn't achieved by it. (especially since my ice1712 needs a lot of magic added (sample rate converter, buffer, dmix), thats why i want it to be the 'default' device) I only see one problem for this in the future: I was able to distinguish the cards by module. But what happens, if someone has the same card several times (same module)? Rely on PCI bus ordering? A new PCI quirk for your mainboard to handle a transparent bridge and then? Multithreaded probing anyone? (You can strongly object to a feature like this, but it is desirable from a users POV, like starting [xkg]dm as early as possible, to bring the user a login screen, while cups and foo and bar still starting in the background). Please keep in mind, that Linux is predestinated for such use ;) Drivers which can handle several instances of the same card (and if not, you can fix it), ALSA as a fine API, good latency with mostly every card, continued improvements to the core kernel, directly available to the user (thanks to stable-API-nonsense.txt *everything* can be fixed/improved, even if it means a transition for everyone), to raise (IPC) performance and lower latency in every subsystem (pushed forward by people with other kind of problems, like > 1k processors (go SGI, go;), not only "the sound freaks") and RT for the extra fun to build a cheap recording machine for example. But i think i don't tell anyone news on this, and i extravagate... > Regards, > Clemens > With best wishes and thanks to all who helped, Jan PS: Sorry for any shortcomings in my english, don't had the time to proof read it 20 times. -- Coffeecup empty - Userpanic! ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-devel
