I've reported this several times through several channels, not sure if yet another report will have an impact. Here a quick summary of doc-generation-related issues:

From a packager maintainer POV, it's totally unpredictable if/when documentation gets built, see e.g. http://hackage.haskell.org/package/GLURaw-2.0.0.1: Currently there are no docs, while the previous version had docs, and the only change was relaxing the upper bound of OpenGLRaw (https://github.com/haskell-opengl/GLURaw/compare/v2.0.0.0...v2.0.0.1). Basically I gave up any hope and rely on stackage and/or local docs... :-(

Cheers,

   S.