Okay…that link above, oh and hello, is chip select for SPIDEV2 which is located in Linux on /dev/ but! Yes but…I want to warn you. If you change some .dts or add a .dtbo file, the board may fail to boot.
If the board fails to boot and you do not know why it is failing to boot, that is not smart. For instance, BBB.io persons made a header, three pin, on the AI to add a connection to TTY to USB ‘dongle’/converter.
Anyway, you can use the dongle to hopefully break into the serial console or find a way into uboot. Now, uboot is out of my scope. So, maybe another person will jump in if we make that far.
Okay…hopefully you are getting excited about helping me helping you helping us? Anyway…um, I will keep searching for the rest of the Controller In Peripheral Out && Controller Out Peripheral In on the .dtsi listed above. Then, I will find clock too.