drm/i915/edp: Get the Panel Power Off timestamp after panel is off
authorManasi Navare <manasi.d.navare@intel.com>
Wed, 4 Oct 2017 16:48:26 +0000 (09:48 -0700)
committerJani Nikula <jani.nikula@intel.com>
Thu, 5 Oct 2017 06:43:12 +0000 (09:43 +0300)
commitcbacf02e7796fea02e5c6e46c90ed7cbe9e6f2c0
tree7b97929621675c2b6b8a0e2d723c04d802f2caa6
parent5ea2355a100a3c6304901d058aee06d3a6be69bc
drm/i915/edp: Get the Panel Power Off timestamp after panel is off

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@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: stable@vger.kernel.org
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@ffwll.ch>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507135706-17147-1-git-send-email-manasi.d.navare@intel.com
drivers/gpu/drm/i915/intel_dp.c