pcm - Alsa combine 2 cards sound

Question

I've on my board 2 sound card. The main one is Card0 and i can use it with alsa for some application. The second one is an usb virtual sound card from a module gsm. I installed the usb gsm driver to put audio through usb and i can found the second sound card when i make "aplay -l".

root@colibri-imx7:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: imx7colibrisgtl [imx7-colibri-sgtl5000], device 0: HiFi sgtl5000-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Android [Android], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

When i make a gsm call between module gsm and a phone, i can make this command to hear my sample wav throught the phone : aplay -D sysdefault:CARD=Android sample.wav

So now i want to talk through the mic and hear on the speaker connected to the sound card 0. Is it possible with Alsa ? what i need ? add pcm.multi to my asound.conf file ? I dont know exactly what i need to change in alsa conf.

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Thank you for your help.

question from:https://stackoverflow.com/questions/65830916/alsa-combine-2-cards-sound

Answer 1

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