The documentation contains the below text, with the description of the DT entry being empty.
I would have expected to see
bitclock-master
frame-master
When the codec operates in master mode, the codec I2S bit clock typically is driven by the codec’s internal PLL, which is driven in turn by a fixed rate external clock source. The properties below must be set in the appropriate DAI link to indicate that the codec should operate in master mode.
nvidia,dai-link-x {};
The R28 documentation does not cover this topic.