Merge tag 'drm-vc4-next-2016-03-14' of github.com:anholt/linux into drm-next

Merge tag 'drm-vc4-next-2016-03-14' of github.com:anholt/linux into drm-next

This pull request covers what's left for 4.6.  Notably, it includes a
significant 3D performance improvement and a fix to HDMI hotplug
detection for the Pi2/3.

* tag 'drm-vc4-next-2016-03-14' of github.com:anholt/linux:
  drm/vc4: Recognize a more specific compatible string for V3D.
  dt-bindings: Add binding docs for V3D.
  drm/vc4: Return -EFAULT on copy_from_user() failure
  drm/vc4: Respect GPIO_ACTIVE_LOW on HDMI HPD if set in the devicetree.
  drm/vc4: Let gpiolib know that we're OK with sleeping for HPD.
  drm/vc4: improve throughput by pipelining binning and rendering jobs