I'm trying to install the DAC+DSP on a RPi 3b+ with Raspbian to record and playback audio, so I followed this post:
https://www.hifiberry.com/docs/software/configuring-linux-3-18-x/
But it looks like the sound card isn't recognized. In fact, this page doesn't have a specific dtoverlay for the DAC+DSP card, so I used the note here:
https://www.hifiberry.com/docs/software/using-the-dac-dsp-to-record-audio-from-s-pdif/
dtoverlay=hifiberry-dacplusdsp
But it looks like the sound card isn't recognized.
I went through some debugging and noticed:
sudo vcdbg log msg
...
001923.044: dtdebug: Failed to open overlay file 'overlays/hifiberry-dacplusdsp.dtbo'
001938.274: dtdebug: Failed to open overlay file 'overlays/hifiberry-dacplusdsp-overlay.dtb'
001953.506: dtdebug: Failed to open overlay file 'overlays/hifiberry-dacplusdsp.dtb'
Sure enough, those files don't exist in /boot/overlays. What's my next step?