"Perfect woman" (J.J. Cale)

I still don't hear any chord changes in this, just the Cm (or C5)....

The main riff varies somewhat along the way, but here's approximation of the way it's played at around 51s:

---------------------------
---------------------------
-----------------------5-5-
-----------------5~--5-----
---1-3~---3--6-3-----------
-3-------------------------

--------------------
--------------------
-3------------------
---5-3-5-3----------
-----------6-3---3~-
--------------------

Basically that looks to me like a Cm7 arpeggio.