On the other hand, how the Chinese system of "openness" works means that detailed hardware documentation is often freely available if you know where to look, even that which would be NDA'd and basically impossible to get from a Western company:
Consider if the SoC was from Broadcom or Qualcomm or some other Western company. You'd probably be able to get source code, but having that doesn't show as much about what else the hardware can do as they're not going to share datasheets with you (and there's unlikely to be anyone willing to leak them either.)
Edit: have you looked at Ingenic's site? They have what appears to be Linux source code available:
Yes, and many times to get that information you need to find someone to contact, talk to them, present yourself as a good connection, and hope that they actually give you what you ask for.
http://www.bunniestudios.com/blog/?p=4297
Consider if the SoC was from Broadcom or Qualcomm or some other Western company. You'd probably be able to get source code, but having that doesn't show as much about what else the hardware can do as they're not going to share datasheets with you (and there's unlikely to be anyone willing to leak them either.)
Edit: have you looked at Ingenic's site? They have what appears to be Linux source code available:
http://www.ingenic.cn/en/?product/id/6/lm/1.html