Reading the register definitions (starting on page 95 of DS), and reading the through the 'scripts' in chapter 4, I have fair confidence that the default settings have DIN routed in stereo to DAC until configuration steps are taken to break that.
Reading one of the scripts in chapter 4 gives me the impression that MICPGA may be routed to DOUT by default but I can't see confirming details in the register definitions and trying for the life of me to find anything in the datasheet which makes configuring the source of DOUT as direct from ADC or direct from MICPGA or anything other than some clocks (and a secondary audio interface which isn't detailed abundantly either, afaict) is starting to hurt my head.
Please forgive (1) my tired eyes and (2) my boss for not even handing me hardware yet but telling me he expects results moments after handing it to me.
If you can point out the part of SLAA408A I should have noticed by now and you do I will be embarrassed but very grateful none-the-less.
If you can link something Google (or TI search mechanism) would have shown me for a 'sensible query' I will very grateful to know your search term(s) as well as, of course, for the link.