[alsa-devel] [PATCH 0/4] i915 to call hda driver on HDMI plug/unplug

[David Henningsson]

This patch set aims to resolve three problems:

 * The first - and most serious one - is that the audio driver is not woken up
   properly when in power save modes, especially not when the HDA controller is
   in D3. By having the i915 driver call directly into the hda driver, the HDA
   driver is always notified that an HDMI hotplug event has happened.

 * Second, there is currently no way for userspace to match an HDMI audio output
   with an HDMI video output. We fix this by sending connector_type and
   connector_type_id in the HDMI hotplug callback.

 * Third, writing ELD info to the hardware just so the HDA driver can read it
   from the hardware seems a bit inefficient. We could just pass that information
   in the callback, too.

The patch in its current form fixes the first of these problems and provides most
of the infrastructure for the second and third problem. 

The patch set is based on 4.2rc2 + my recent codec wakeup patch. So far, it has
been tested (and working) on one Skylake machine.

David Henningsson (4):
  drm/i915: Add audio hotplug info struct
  drm/i915: Call audio hotplug notify function
  ALSA: hda - Dispatch incoming HDMI hotplug i915 callback
  ALSA: hda - Wake the codec up on hotplug notify events

 drivers/gpu/drm/i915/i915_drv.h    |    1 +
 drivers/gpu/drm/i915/intel_audio.c |   46 ++++++++++++++++++++++++++++++++++++
 include/drm/i915_component.h       |   19 +++++++++++++++
 include/sound/hdaudio.h            |    4 ++++
 sound/hda/hdac_i915.c              |   24 +++++++++++++++++++
 sound/pci/hda/patch_hdmi.c         |   22 ++++++++++++++++-
 6 files changed, 115 insertions(+), 1 deletion(-)

-- 
1.7.9.5