Google "broadsheet e ink" S1D13521 ties into that (either thats its street name or something) there appears to be a broadsheet driver in embedded linux already.
http://developer.txtr.com/Broadsheet...oller_S1D13521
http://lxr.free-electrons.com/source...broadsheetfb.c
A friend of mine enhanced the image from the PE teardown someone posted and it looks like (regardless of the name of the driver) they are using the 3521. This has most of the same capabilities from the info sheet From what I can read on the tweaked zoom the chip says
Epson
D13521183
--stuff---
EINK