I2C

https://sourceforge.net/projects/ch341eepromtool/

dpavlin@nuc:/nuc/ch341a/ch341eepromtool_0.5$ gcc -o ch341eeprom ch341eeprom.c ch341funcs.c -lusb-1.0
dpavlin@nuc:/nuc/ch341a/ch341eepromtool_0.5$ 
dpavlin@nuc:/nuc/ch341a/ch341eepromtool_0.5$ ./ch341eeprom 
ch341eeprom - an i2c EEPROM programming tool for the WCH CH341a IC
Version 0.5 copyright (c) 2011  asbokid <ballymunboy@gmail.com>

This program comes with asbolutely no warranty; This is free software,
and you are welcome to redistribute it under certain conditions:
GNU GPL v3 License: http://www.gnu.org/licenses/gpl.html

Usage:
 -h, --help             display this text
 -v, --verbose          verbose output
 -d, --debug            debug output
 -s, --size             size of EEPROM {24c32|24c64}
 -e, --erase            erase EEPROM (fill with 0xff)
 -w, --write <filename> write EEPROM with image from filename
 -r, --read  <filename> read EEPROM and save image to filename

Example:  ch341eeprom -v -s 24c64 -w bootrom.bin

SPI

git clone https://github.com/urjaman/flashrom/
git checkout -b origin/ch341a origin/ch341a

dpavlin@nuc:/nuc/flashrom$ sudo apt-get install pciutils-dev