That lens is made to work with the Chinon CP-9AF, an early auto focus film camera. The basic mount is the same as the Pentax K Mount, but the electrical contacts are located differently. Chinon only made three lenses in this mount: a 28-80, a 35-135 (very rare) and the 70-210mm that you have.
Pentax K Mount lenses will work as manual focus lenses on the Chinon CP-9AF. You would also need to manually focus the Chinon 70-210mm lens on a Pentax body (which might be a little awkward) by turning the barrel just behind the lens cap.
Since there is no aperture ring on the lens, you would need a post-1983 Pentax or Chinon body with Pentax K-A, K-AF, K-AF2, or K-A2 connectors to operate the aperture lever using the camera to select the aperture setting. If you used an adapter to use the lens on any non Pentax body you would have no way to control the aperture.