We used to have a version 0.1 without source code copyright notice in our
repository for tichksum because we did not know exactly where it was from.
Just the name implied that it was from Texas Instruments. I still could not
find a download location at ti.com, but at least I found a version of the
source code which contains original TI copyright notices. I copied them into
our own bug-fixed version.

I got the copyright notices from
  * https://dev.openwrt.org/attachment/ticket/1411/dsl-502t-openwrt-2.4-1.patch
    (where I actually found it via web search)
  * http://itee.uq.edu.au/~chrisp/DSL-502T_OpenWRT/dsl-502t-openwrt-2.4-1.patch
    (this is the place mentioned as the origin of the OpenWrt patch)

Where this guy Chris Pascoe got the source code from I have no idea, but we do
gratefully acknowledge TI's copyright.
--
Alexander Kriegisch
http://freetz.org