At Tue, 11 Nov 2008 12:21:30 +0100, Jelle de Jong wrote: > > Jaroslav Kysela wrote: > > 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 > > I wish it was as simple as using the [identification ]. The [id..] is > not reliable for one usb port, as you can below I just unplugged some > usb audio devices and plugged it in again. The [id] does not match the > same usb location port anymore, so breaking the > user->unique-usb-port-audio-device connection. > > Being able to set the id with udev would be an possible solution. Ah, indeed. I vaguely remember why I wrote that patch... > cat /proc/asound/cards (first) > 0 [Intel ]: HDA-Intel - HDA Intel > HDA Intel at 0xf7db8000 irq 16 > 1 [pcsp ]: PC-Speaker - pcsp > Internal PC-Speaker at port 0x61 > 2 [Em28xx Audio ]: Empia Em28xx AudEm28xx Audio - Em28xx Audio > Empia Em28xx Audio > 3 [default ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.1, full speed > 4 [default_1 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.2, full speed > 5 [default_2 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.3, full speed > 6 [default_3 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.4, full speed > > cat /proc/asound/cards (second) > 0 [Intel ]: HDA-Intel - HDA Intel > HDA Intel at 0xf7db8000 irq 16 > 1 [pcsp ]: PC-Speaker - pcsp > Internal PC-Speaker at port 0x61 > 3 [default ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.3, full speed > 4 [default_1 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.2, full speed > 5 [default_2 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.4, full speed > 6 [default_3 ]: USB-Audio - USB AUDIO > USB AUDIO at usb-0000:00:1d.7-4.1, full speed > > Also the limitation of [0-7] devices is kind of unclear does it > something to do with limitations of timers? No, it's just an issue of minor device assignment. Depending on the kernel configuration, you'll be able to have more devices. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
