[Intel-gfx] [PATCH v2 1/2] drm/i915/edp: Get the Panel Power Off timestamp after panel is off

[Manasi Navare]

Kernel stores the time in jiffies at which the eDP panel is turned
off. This should be obtained after the panel is off (after the
wait_panel_off). When we next attempt to turn the panel on, we
use the difference between the timestamp at which we want to turn the
panel on and timestamp at which panel was turned off to ensure that this
is equal to panel power cycle delay and if not we wait for the remaining
time. Not waiting for the panel power cycle delay can cause the panel to not
turn on giving rise to AUX timeouts for the attempted AUX transactions.

v2:
* Separate lines for bugzilla (Jani Nikula)
* Suggested by tag (Daniel Vetter)

Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101518
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101144
Suggested-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
Reviewed-by:  Daniel Vetter <daniel.vetter at ffwll.ch>
Reviewed-by: Jani Nikula <jani.nikula at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 90e756c..0fd41cd 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2308,8 +2308,8 @@ static void edp_panel_off(struct intel_dp *intel_dp)
 	I915_WRITE(pp_ctrl_reg, pp);
 	POSTING_READ(pp_ctrl_reg);
 
-	intel_dp->panel_power_off_time = ktime_get_boottime();
 	wait_panel_off(intel_dp);
+	intel_dp->panel_power_off_time = ktime_get_boottime();
 
 	/* We got a reference when we enabled the VDD. */
 	intel_display_power_put(dev_priv, intel_dp->aux_power_domain);
-- 
2.1.4