Free firmware for e-book reader

Question

linux

Does anyone know if there are projects similar to RockBox , but only for e-ink readers?
Or maybe there is some particular reader for which someone has already made a tolerable custom firmware?
Or, at worst, is there any specific reader with an open specification for which you could build your own Linux?

Answer 1

There is something : iplinux.org/openinkpot.org/

Answer 2

NOT quite a firmware (although it is called that), but interesting.
ebookapplications.com/
For Sony e- readers

Answer 3

Hello.
And which manufacturer of readers are interested in?

Answer 4

for nuks they are quite actively developing