[Intel-gfx] [PATCH] drm/i915: cache the EDID for eDP panels

[Chris Wilson]

On Thu, 14 Jun 2012 15:28:33 -0400, Jesse Barnes <jbarnes at virtuousgeek.org> wrote:
> They aren't going anywhere, and probing on DDC can cause the panel to
> blank briefly, so read them up front and cache them for later queries.
> 
> v2: fix potential NULL derefs in intel_dp_get_edid_modes and
>     intel_dp_get_edid (Jani)
>     copy full EDID length, including extension blocks (Takashi)
>     free EDID on teardown (Takashi)
> v3: malloc a new EDID buffer that's big enough for the memcpy (Chris)
> v4: change handling of NULL EDIDs, just preserve the NULL behavior
>     across detects and mode list fetches rather than trying to re-fetch
>     the EDID (Chris)
> v5: be glad that Chris is around to remind me to hit C-x C-s before
>     committing.

I do 'git add' reminders as well; by appointment only.

And now to really pour rain on your fire. Why are we repeating quite
obscure logic from intel_modes.c? Can we not export a function to attach
an edid to a connector and then refactor intel_dp.c to only have a
single edid reader where you could add your magic eDP EDID cache
handling in single place.

So intel_dp_get_edid_modes calls intel_dp_get_edid() and
intel_connector_attach_edid() rather the single-shot
intel_ddc_get_modes().
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre