I'm wanting to make my SD card read-only and add an external I2C flash such as one of these for storing a few small config files. My config files are 5-6KB but I want a bit of room to grow hence I want a filesystem with at least 64KB/512KBit of room. OS is Raspbian Stretch Lite.
I know this is typically done with SPI or SDIO but I'm running low on pins.
So my questions:
1.) What kind of filesystem can I use to mount I2C flash?
2.) What is the minimum size I should look at considering filesystem overhead?
I thought of SPIFFS but it looks to be a work in progress, and no mention of I2C support.