Implement DAC-based audio (audioio) on Espressif

[dhalbert]

The DAC(s) support DMA, but it's not in the ESP-IDF API yet: espressif/esp-idf#6333. So we would wait for that.

[275RR]

any update on this? I have a a MagTag

[ladyada]

i think we were seeing weird results, when @jepler is back we can follow up with espressif on whether they fixed DMA DAC support on the S2

[gpeyton]

@jepler @ladyada any update on this?

[ladyada]

@gpeyton since you are bumping - please check with espressif if they have DMA support for the ESP32-S2 DAC, that was our hold up as you can read above

[tmkasun]

@ladyada and team, it looks like DAC DMA is now supported in Espressif: https://github.com/espressif/esp-idf/blob/master/components/esp_driver_dac/esp32s2/dac_dma.c.

If you could provide some guidance, I’d be happy to work on adding this support to CircuitPython.