FTDI is used at run time in 3 crates (of which 1 optionally). It's used only as a dev dependency in 2 crates.

Depender (with downloads and own rev deps) FTDI version
1.5K 8 ftdi-embedded-hal optional ^0.1.3
jtag ^0.1.3
obd2 ^0.1
bme280-rs dev ^0.1
scd4x-rs dev ^0.1