Comment 1 for bug 1490895

This is a patch set fixing a long-standing bug for some Haswell, Broadwell and most Skylake machines.

When the HDA audio controller is in D3, a hotplug event (i e, HDMI or DisplayPort being plugged in) fails to wake up the audio side so it never registers that something has happened.

By having the i915 driver call directly into the hda driver, the HDA driver is always notified that an HDMI hotplug event has happened.

I've been trying to get this through upstream, but it has been slower than usual due to it touching both the i915 and HDA subsystems, and ideally I wanted it in there first, but I don't think OEM wants to miss another SRU cycle. So this is on its way in upstream, but not there yet. The patches here are based on v5 of my patch set, and v4 were both reviewed by Jani Nikula and Takashi Iwai.

Now, I've tested the upstream version, but I've just backported this to 3.19 without any testing. I could use Timo's assistance here so we coordinate testing this with other i915 changes for the next SRU cycle. And I could use Timo's help to make sure this applies equally to i915 and i915_bpo.

BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1490895

David Henningsson (4):
  drm/i915: Add audio pin sense / ELD callback
  drm/i915: Call audio pin/ELD notify function
  ALSA: hda - allow codecs to access the i915 pin/ELD callback
  ALSA: hda - Wake the codec up on pin/ELD notify events

 drivers/gpu/drm/i915/i915_drv.h | 1 +
 drivers/gpu/drm/i915/intel_audio.c | 27 ++++++++++++++++++++++++---
 include/drm/i915_component.h | 16 ++++++++++++++++
 sound/pci/hda/hda_i915.c | 10 ++++++++++
 sound/pci/hda/hda_intel.h | 5 +++++
 sound/pci/hda/patch_hdmi.c | 21 ++++++++++++++++++++-
 6 files changed, 76 insertions(+), 4 deletions(-)

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1.9.1