[alsa-devel] ALSA: How to create multiple cards?

Truong Hoang truonghn at gmail.com
Fri Aug 6 05:11:26 CEST 2010

Hi all,

I have a problem that I need help from the ALSA experts.

I want to write an alsa shim .ko which creates multiple cards. Let's assume
2 cards. My program calls
snd_card_create() and snd_card_register() two times. I also has 1 PCM for
each of these card.

After install the .ko to the kernal, I see the /proc/asound has card0 and
card1. But the "aplay -l" sees only card0. The snd_card_next() only returns
0 (i.e. 1 card).
What did I miss in my program? The /dev/snd/ has only hwC0D0 and pcmD0C0p.

I am a beginner in ALSA, so I appreciate if you can give the explanation in

Thank you,

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