Regarding the lack of upstream work, a former Qualcomm VP told me that the major reason they minimize any open source work is that their lawyers are paranoid that any accidental IP leak might endanger their patent-related revenue streams (80% of their pre-tax profits are from patent licensing). Given that patents are public information, I'm not sure I understand the exact logic there, but I've seen this general kind of legal paranoia play out before.
Their non-Android Linux BSPs are especially bad since they're frankensteined together from a subset of their AOSP tree with their only concern being to meet the minimal requirements of some high-volume customer contract.