NACK[B] Re: [PATCH 0/7][SRU][OEM-B][B] drm/i915: Fix hotplug issues

[Timo Aaltonen]

On 23.7.2019 10.37, You-Sheng Yang wrote:
> BugLink: http://bugs.launchpad.net/bugs/1835001
> 
> [Impact]
> System does not always auto detect disconnection of external monitor on
> Intel VGA.
> 
> [Fix]
> Two changes from drm-intel tree along with their prerequisites are
> necessary to introduce hotplug retrying to fix this issue. They are:
> 
>   * drm/i915: Add support for retrying hotplug
>   * drm/i915: Enable hotplug retry
> 
> All the prerequisites have been landed to kernel mainline, but the
> target two changes have not.
> 
> [Test Case]
> 1. open "system settings > display settings"
> 2. connect laptop to an external HDMI monitor via HDMI port & cable
> 3. unplug the HDMI cable
> 4. check if "display settings" automatically detects the removal of the
> external monitor
> 
> [Regression potential]
> Medium. For all the prerequisites they have been landed since 4.18, and
> the last two patches will only be merged some time later. Basically it
> turns a currently existing kernel work to a delayed work so that it may
> retry probing HDMI hotplug status.
> 
> Imre Deak (1):
>   drm/i915: Add support for retrying hotplug
> 
> José Roberto de Souza (1):
>   drm/i915: Enable hotplug retry
> 
> Ville Syrjälä (5):
>   drm/i915: Convert intel_hpd_irq_event() into an encoder hotplug hook
>   drm/i915: Reinitialize sink scrambling/TMDS clock ratio on HPD
>   drm/i915: Move SST DP link retraining into the ->post_hotplug() hook
>   drm/i915: Nuke intel_dp->channel_eq_status
>   drm/i915: Track whether the DP link is trained or not
> 
>  drivers/gpu/drm/i915/i915_debugfs.c           |   2 +
>  drivers/gpu/drm/i915/i915_drv.h               |   3 +-
>  drivers/gpu/drm/i915/intel_crt.c              |   4 +-
>  drivers/gpu/drm/i915/intel_ddi.c              | 171 +++++++++++++++++
>  drivers/gpu/drm/i915/intel_dp.c               | 179 +++++++++++++-----
>  drivers/gpu/drm/i915/intel_dp_link_training.c |   8 +-
>  drivers/gpu/drm/i915/intel_drv.h              |  18 +-
>  drivers/gpu/drm/i915/intel_hdmi.c             |  27 +++
>  drivers/gpu/drm/i915/intel_hotplug.c          |  76 ++++++--
>  drivers/gpu/drm/i915/intel_sdvo.c             |  14 +-
>  10 files changed, 423 insertions(+), 79 deletions(-)
> 

This wasn't originally meant for bionic, so let's not risk regressing it.


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