On Tue, 11 Nov 2008, Takashi Iwai wrote:
Almost all devices can be managed with udev rules, that is where the system is designed for, there are also alsa rules in there, if they don't work what is wrong then? is it an alsa issue, or udev, what are the dependencies when alsa uses hardware. How are the /dev/snd/* devices used and what is the /proc/asound/* for ?
The card index mechanism in ALSA was introduced much before udev was born. It's just a legacy mechanism, but it's hard to kill without breaking the running system, unfortunately.
Note that you can identify your card via the text identification (check /proc/asound/cards to get it in []). You can set this identification in the module insert time and use for example 'hw:Intel' in your apps without bothering with indexes.
The missing part is the modification of this text identification using sysfs at runtime for udev. Some time ago, I was trying to add this setup to /sys/class/sound, but the sysfs core code was not prepared for this change. I'll try to check the situation again.
Jaroslav ----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.