Patch "drm/i915/lspcon: Enable AUX interrupts for resume time initialization" has been added to the 4.10-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    drm/i915/lspcon: Enable AUX interrupts for resume time initialization

to the 4.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-i915-lspcon-enable-aux-interrupts-for-resume-time-initialization.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 908764f6d0bd1ba496cb8da33b9b98297ed27351 Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@intel.com>
Date: Tue, 29 Nov 2016 21:40:29 +0200
Subject: drm/i915/lspcon: Enable AUX interrupts for resume time initialization
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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From: Imre Deak <imre.deak@intel.com>

commit 908764f6d0bd1ba496cb8da33b9b98297ed27351 upstream.

For LSPCON initialization during system resume we need AUX
functionality, but we call the corresponding encoder reset hook with all
interrupts disabled. Without interrupts we'll do a poll-wait for AUX
transfer completions, which adds a significant delay if the transfers
timeout/need to be retried for some reason.

Fix this by enabling interrupts before calling the reset hooks. Note
that while this will enable AUX interrupts it will keep HPD interrupts
disabled, in a similar way to the init time output setup code.

This issue existed since LSPCON support was added.

v2:
- Rebased on drm-tip.

Cc: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: David Weinehall <david.weinehall@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480448429-27739-1-git-send-email-imre.deak@intel.com
(rebased onto v4.10.4 due to missing s/dev/dev_priv/ upstream change)
(corrected stable tag)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/i915/i915_drv.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1573,18 +1573,21 @@ static int i915_drm_resume(struct drm_de
 	intel_opregion_setup(dev_priv);
 
 	intel_init_pch_refclk(dev);
-	drm_mode_config_reset(dev);
 
 	/*
 	 * Interrupts have to be enabled before any batches are run. If not the
 	 * GPU will hang. i915_gem_init_hw() will initiate batches to
 	 * update/restore the context.
 	 *
+	 * drm_mode_config_reset() needs AUX interrupts.
+	 *
 	 * Modeset enabling in intel_modeset_init_hw() also needs working
 	 * interrupts.
 	 */
 	intel_runtime_pm_enable_interrupts(dev_priv);
 
+	drm_mode_config_reset(dev);
+
 	mutex_lock(&dev->struct_mutex);
 	if (i915_gem_init_hw(dev)) {
 		DRM_ERROR("failed to re-initialize GPU, declaring wedged!\n");


Patches currently in stable-queue which might be from imre.deak@intel.com are

queue-4.10/drm-i915-lspcon-fix-resume-time-initialization-due-to-unasserted-hpd.patch
queue-4.10/drm-i915-lspcon-enable-aux-interrupts-for-resume-time-initialization.patch
queue-4.10/drm-i915-gen9-enable-hotplug-detection-early.patch