From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> We are no longer checkling the DP link status on long hpd. We used to do that from the .hot_plug() handler, but it was removed when MST got introduced. If there's no userspace we now fail to retrain the link if the sink power is toggled (or cable yanked and replugged), meaning the user is left staring at a blank screen. With the retraining put back that should be fixed. Also remove the leftover comment that referred to the old retraining from .hot_plug(). Fixes a regression introduced in: commit 0e32b39ceed665bfa4a77a4bc307b6652b991632 Author: Dave Airlie <airlied@xxxxxxxxxx> Date: Fri May 2 14:02:48 2014 +1000 drm/i915: add DP 1.2 MST support (v0.7) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89453 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91407 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89461 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89594 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=85641 Cc: Dave Airlie <airlied@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index d32ce48..b014158 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -5024,9 +5024,12 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) intel_dp_probe_oui(intel_dp); - if (!intel_dp_probe_mst(intel_dp)) + if (!intel_dp_probe_mst(intel_dp)) { + drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); + intel_dp_check_link_status(intel_dp); + drm_modeset_unlock(&dev->mode_config.connection_mutex); goto mst_fail; - + } } else { if (intel_dp->is_mst) { if (intel_dp_check_mst_status(intel_dp) == -EINVAL) @@ -5034,10 +5037,6 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) } if (!intel_dp->is_mst) { - /* - * we'll check the link status via the normal hot plug path later - - * but for short hpds we should check it now - */ drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); intel_dp_check_link_status(intel_dp); drm_modeset_unlock(&dev->mode_config.connection_mutex); -- 2.4.6 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html