[Intel-gfx] [PATCH v2] drm/i915/eDP: When enabling panel VDD cancel pending disable worker

[Egbert Eich]

Before testing if the panel VDD is enabled on eDP cancel any pending
disable worker. This makes sure the worker will be triggered with a
delay from the last time edp_panel_vdd_schedule_off() is called, not
the first time. This avoids unnecessary overhead.

https://bugs.freedesktop.org/show_bug.cgi?id=86201

v2: use cancel_delayed_work() instead of cancel_delayed_work_sync()
as the pps_mutexes will provide the required serialization with
edp_panel_vdd_work() while the sync variant may deadlock. Suggested
by Ville Syrjälä <ville.syrjala at linux.intel.com>.
Made commit message a bit clearer.

Signed-off-by: Egbert Eich <eich at suse.de>
---
 drivers/gpu/drm/i915/intel_dp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 70bb8d0b..7ab39d4 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1503,6 +1503,7 @@ static bool edp_panel_vdd_on(struct intel_dp *intel_dp)
 	if (!is_edp(intel_dp))
 		return false;
 
+	cancel_delayed_work(&intel_dp->panel_vdd_work);
 	intel_dp->want_panel_vdd = true;
 
 	if (edp_have_panel_vdd(intel_dp))
-- 
1.8.4.5