[SOLVED] ALSA: Layla24 module loaded but no sound card

MisterBark · 09-28-2014, 11:23 AM

Hi!

SYSTEM:
- Base Slackware 64 14.1 but most things recompiled from sources, so this is not Slackware specific, just Linux specific.
- Kernel 3.14.12-preempt
- Alsa 1.0.28 (but Alsa Driver from kernel of course)
- Sound Card: Echo Layla24

ISSUE:
alsamixer and /proc/asound don't show the layla24, it does show a midisport 4x4 though.
Booting on original Slackware kernel does not change anything (although the layla24 module gets loaded too)
An Ubuntu 3.2.0-23-lowlatency is installed on the same computer and Layla works with it.

EXPERIMENT:
I renamed snd-layla24.ko in ubuntu, rebooted, then renamed it back and loaded the module manually. Then I don't see the soundcard.
Because of that experiment, I believe that I am simply forgetting something, which leads us to my main question:

=> Loading a soundcard module does not seem to be enough for a card to be listed by alsa in /proc/asound.
Then what else does it need?

lsmod | grep -i snd (on 3.14.12-preempt)

Code:

snd_usb_audio         115025  0 
snd_usbmidi_lib        18316  1 snd_usb_audio
snd_hwdep               5660  1 snd_usb_audio
snd_layla24            26503  0 
snd_rawmidi            17238  2 snd_layla24,snd_usbmidi_lib

(Note that Alsa itself / snd is in the kernel, not as a module)

THANK YOU!

MisterBark · 10-02-2014, 09:39 PM

Bump!
Sorry for that, but after 300 views in 5 days, no reply.
Did I post in the most appropriate section of the forum?
Thanks.

MisterBark · 10-09-2014, 08:03 PM

I answer to my own question

============================
I FOUND THE SOLUTION
============================

Quote:

Originally Posted by MisterBark

=> Loading a soundcard module does not seem to be enough for a card to be listed by alsa in /proc/asound.
Then what else does it need?

Some soundcards like Echo Corporation also need the firmware...
You have to build the alsa-firmware package, then copy the relevant .fw file to a firmware directory that alsa will be able to find.
Personally, I copied everything in a custom /usr/local/ directory, then created some symlinks from a bit everywhere, such as /lib/firmware/echoaudio

After that, reloading the kernel module(s) and/or force-reload on alsa does not seem to be enough for some reasons. So it worked after a reboot.