Hello, I have few questions about upstreaming support for the Turris Omnia into u-boot.
The Turris Omnia has (on I2C interface) an Atmel ATSHA204 CryptoAuthentication chip for storage of MAC adresses, device serial number, device configuration (1 GB RAM vs 2 GB RAM). This data is stored in the internal EEPROM of ATSHA204. The chip is capable of more: for example there is also a random number generator. For more info see http://www.atmel.com/Images/Atmel-8740-CryptoAuth-ATSHA204-Datasheet.pdf
I want to write support for the ATSHA204 for upstream U-Boot so that I can then continue working on support for Turris Omnia. Currently we have our internal branch of U-Boot, in which the ATSHA204 code is in drivers/misc (see https://gitlab.labs.nic.cz/turris/turris-omnia-uboot/blob/master/drivers/mis... ).
My question: Does U-Boot have a standard approach how to write a driver for such a chip? Does this device need to be defined in the Device Tree?
Thank you.
Marek