[Intel-gfx] Displayport Compliance Testing V3

[Todd Previte]

These are the kernel-side patches to enable Displayport compliance testing for 
the i915 driver. They establish a framework and operational parameters for 
compliance testing operations on the i915 driver. Structure is in place such 
that more tests can be added in the near future. Combined with the userspace 
application (currently being integrated into the intel-gnu-tools tree) these 
patches enable the following tests:
        4.2.1.1 Source DUT Retry on No-Reply During AUX Read after HPD Plug Event
        4.2.1.2 Source Retry on Invalid Reply During AUX Read after HPD Plug Event
        4.2.2.1 EDID Read upon HPD Plug Event
        4.2.2.2 DPCD Receiver Capability Read upon HPD Plug Event
        4.2.2.3 EDID Read
        4.2.2.4 EDID Read Failure #1: I2C-Over-AUX NACK
        4.2.2.5 EDID Read Failure #2: I2C-Over-AUX DEFER
        4.2.2.6 EDID Corruption Detection
Without the user app to set the required video mode, some of these tests will 
still pass. 4.2.1.1 and 4.2.1.2 do not require the user app, nor does 4.2.2.2. 
Some of the others may pass with warnings about the video mode not being set 
correctly, depending on your test device. Documentation for using the userspace 
app and an overview of this implementation is available with the user app.

drm/i915: Add debugfs write and test param parsing functions for DP test control
drm/i915: Add new debugfs file for Displaypor compliance test control
drm/i915: Update intel_dp_hpd_pulse() to check link status for non-MST operation
drm/i915: Update intel_dp_compute_config() to handle compliance test requests
drm/i915: Update the EDID automated compliance test function
drm/i915: Add debugfs functions for Displayport compliance testing
drm/i915: Add a delay in Displayport AUX transactions for compliance testing
drm/i915: Update intel_dp_check_link_status() for Displayport compliance testing
drm/i915: Add automated testing support for Displayport compliance testing

drivers/gpu/drm/i915/i915_debugfs.c | 643 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_dp.c     | 249 ++++++++++++++++++++----
drivers/gpu/drm/i915/intel_drv.h    |  18 ++
3 files changed, 870 insertions(+), 40 deletions(-)