[RFC] drm + i915 DP MST code preview

[Dave Airlie]

Hi,

Branch: http://cgit.freedesktop.org/~airlied/linux/log/?h=drm-i915-mst-support

Okay I've gotten this to light up some monitors using -modesetting so it
must be ready for an initial posting,

Tested on Haswell so far with Lenovo Ultradock and with Ancell MST Hub devices,
(checked it can detect the Dell 32" Monitor - but that is another world of pain).

The main problem is documented in the i915 patch, state check backtraces abound.

There is still quite a bit of work todo for a compliant solution, but I don't
have a compliance tester so I can only imagine the fail.

The helper interface can probably be cleaned up, the whole ACT area is bit
of a mess, and I'd probably need an idea from other GPUs how best to do that,

Dave.