Hi Hin-Tak
it was not setting .non_legacy_dai_naming - this was a 4.16 change . The similar hardware but working sibling device has one single ADC codec, while the broken device has two such ADC codec plus a 3rd DAC codec; I see that this flag started to matter in v5.6 for codec2codec links . I don't know if this qualifies as a codec 2 codec link - it is running two 4-mic ADC in parallel to read from 6 mics...
Anyway, I tried putting that flag in, but it has not fix problem with 5.10, so I am back to trimming the difference between v5.4 and v5.5 slowly.
v5.3 has other big change on ALSA SoC for each driver. Out-of-tree might get this effect.
ASoC: xxxx: use modern dai_link style
For example, 05ab66178cb27ee795aa458b43818d2caa2d3953 ("ASoC: mediatek: mt8173-rt5650-rt5676: use modern dai_link style")
Thank you for your help !!
Best regards --- Kuninori Morimoto