[Intel-gfx] [PATCH] drm/i915: Fix the HDMI hot plug disconnection failure (v2)

[Jani Nikula]

On Mon, 12 Nov 2018, Guang Bai <guang.bai at intel.com> wrote:
> Actually I'm still working on it right now with
> DRM_MODE_CONNECTOR_HDMIA/HDMIB, recommended by James, I'm able to
> differentiate the HDMI or DP even the encoder type is the
> "INTEL_OUTPUT_DDI", I still have the "trybot" intermittent test failures
> with new DRM connector types. Even worse, there is phantom
> "intel_encoder_hotplug()" call following the correct one:
> When connecting both DP and HDMI on the platform, unplug the DP, the
> "i915_hotplug_work_func()" first calls the "intel_encoder_hotplug()"
> with DP encoder, then calls again with HDMI encoder.
> I haven't identified if the work function get queued twice or itself
> is incorrectly identifying wrong encoder hotplut status. Will try to
> get everything cleaned up ASAP.

Frankly I liked the simplicity of [1] over the patch in this thread. It
fixed the real-world use case Chris Chiu has, but I understand that it
still failed the slow unplug HDMI test case you have. The problem is, we
have zero visibility to the test case you have. Is it automated or
manual? Can we see the specs or source code for the test case?

If we have to consider the live status unreliable, it's possible to
devise a pathological test case that will always fail, regardless of
what we do in the driver. Does the test case reflect real world usage?

Also Cc: Ville for input.

BR,
Jani.



[1] http://patchwork.freedesktop.org/patch/msgid/20180925071836.24711-1-jani.nikula@intel.com


-- 
Jani Nikula, Intel Open Source Graphics Center