I2S - output main clock to codec

[ZaneKaminski]

Hello. I have reviewed the I2S driver API found in i2s.h, but I am still not sure about one detail. I need to output the a main clock (16.9344 MHz or 18.432 MHz) to my codec chip. I figured I would synthesize it with the Audio PLL and then configure the I/O mux to output the signal, but I can't find how to do this in the documentation. Am I on the right track? How do I do this?

[ESP_Sprite]

Sorry, as is the audio PLL still is not documented. I also do not know if it's possible to route its output directly to a GPIO.

[Volvox]

As I can see in the new technical reference manual V1.5 the output of the master clock/apll output of both I2S peripherals should now be available via the IO_MUX to specific pin. I checked the actual pinmapping in the actual commit of IDF but I dont find the related i2sn_clk Makros for GPIO mapping documented in the io_mux_reg.h.
Can someone help with the related GPIO Pin and function_no for the mapping? Would be great