Alc271x Datasheet

The driver is snd-hda-codec-realtek. In alc271x_bind you’ll see:

/* alc271x specific setup */
snd_hda_codec_write(codec, 0x20, 0, AC_VERB_SET_PROC_STATE, 0x01);

That enables internal processing. The datasheet won’t explain that – you need Realtek’s application note. alc271x datasheet

The chip typically comes in a QFN (Quad Flat No-leads) 48-pin or 32-pin package depending on the specific sub-model. It requires a 3.3V or 1.5V power supply (depending on the rail) and connects to the system via the HDA Link (SDI/SDO signals, BCLK, SYNC, RST#). The driver is snd-hda-codec-realtek

The ALC271X is fully compatible with Realtek’s Universal HD Audio Driver package. Operating systems supported include: That enables internal processing