Comment 21 for bug 1343543

I completed the bisect, here is the result:

$ git bisect bad fdbc3b1f639bb2cbfb32c612b2699e0ba373317d
fdbc3b1f639bb2cbfb32c612b2699e0ba373317d is the first bad commit

$ git show
commit fdbc3b1f639bb2cbfb32c612b2699e0ba373317d
Author: Jani Nikula <email address hidden>
Date: Tue Nov 12 17:10:13 2013 +0200

    drm/i915/dp: set sink to power down mode on dp disable

    We used to put the local sink and any downstream sinks to power down
    mode at disable or dpms off using the DPCD SET_POWER register, until
    this was broken by

    commit e8cb455876fa8f67c6aba394d0a14b697bf04cc3
    Author: Daniel Vetter <email address hidden>
    Date: Sun Jul 1 13:05:48 2012 +0200

        drm/i915/dp: convert to encoder disable/enable

    Fix it.

    Signed-off-by: Jani Nikula <email address hidden>
    Reviewed-by: Todd Previte <email address hidden>
    Signed-off-by: Daniel Vetter <email address hidden>

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index eb8139d..0b2e842 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1774,7 +1774,7 @@ static void intel_disable_dp(struct intel_encoder *encoder)
         * ensure that we have vdd while we switch off the panel. */
        ironlake_edp_panel_vdd_on(intel_dp);
        ironlake_edp_backlight_off(intel_dp);
- intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
        ironlake_edp_panel_off(intel_dp);

        /* cpu edp my only be disable _after_ the cpu pipe/plane is disabled. */