I've been using the zed_adau1761.c soundcard driver as a guide in writing my own soundcard driver. I have found basically 2 variants of the associated devicetree, one with the property "pcm = <&xilinx_pcm_audio_i2s>;" and one without. The one with it appears to match a xilinx-pcm.c driver.
I'm trying to understand why the 2 variants, because I would have thought one would work and the other not, and I'm currently getting a PCM-related error when I try to use my driver with arecord and I'm trying to understand it.
Is anyone able to enlighten me?