Posted V5 that change the order of the existing flow.
Found Tejas' email address is incorrect. Will correct in V6.
Gareth
> -----Original Message-----
> From: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> Sent: Thursday, April 25, 2024 7:31 PM
> To: Yu, Gareth <gareth.yu@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Yu, Gareth <gareth.yu@xxxxxxxxx>
> Subject: Re: [PATCH] drm/i915/display: Fixed the main link lost in MST
>
> On Thu, 25 Apr 2024, gareth.yu@xxxxxxxxx wrote:
> > From: Gareth Yu <gareth.yu@xxxxxxxxx>
> >
> > Re-train the main link when the sink asserts a HPD for the main lnk
> > lost.
>
> NAK.
>
> Please read the review comments.
>
> BR,
> Jani.
>
> >
> > v4: detect the main link state by intel_dp_needs_link_retrain
> > instead of intel_dp_mst_link_status because the main link
> > state can't detect correctly sometimes by
> > intel_dp_mst_link_status
> >
> > Cc : Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@xxxxxxxxx>
> > Cc : Matt Roper <matthew.d.roper@xxxxxxxxx> Cc : Ville Syrjälä
> > <ville.syrjala@xxxxxxxxxxxxxxx>
> > Signed-off-by: Gareth Yu <gareth.yu@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/display/intel_dp.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> > b/drivers/gpu/drm/i915/display/intel_dp.c
> > index e05e25cd4a94..e1b60303b256 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -5849,8 +5849,14 @@ intel_dp_detect(struct drm_connector
> *connector,
> > /* Can't disconnect eDP */
> > if (intel_dp_is_edp(intel_dp))
> > status = edp_detect(intel_dp);
> > - else if (intel_digital_port_connected(encoder))
> > + else if (intel_digital_port_connected(encoder)) {
> > status = intel_dp_detect_dpcd(intel_dp);
> > + if (status == connector_status_connected && intel_dp->is_mst
> &&
> > + intel_dp_needs_link_retrain(intel_dp)) {
> > + if (intel_dp_retrain_link(encoder, ctx))
> > + status = connector_status_disconnected;
> > + }
> > + }
> > else
> > status = connector_status_disconnected;
>
> --
> Jani Nikula, Intel
