sure you can control the switch via i2c. In fact some basic programming is happening in UBoot to make the switch ASIC shut or flat switch. That is not very convinient for the user. The switch driver port from @User is working on top of the DSA framework (distributed switching arch.) and Netlink API in linux. which allow to model the network layout (aka the switch) via the standard linux network command or frameworks for it like ifupdown-ng. This is more convinient for the user. (And a kind of standard as bigger hardware vendorws which are using Linux also adapting Cumulus Linux, SONiC, etc, even OpenWRT and others are using this.)