From 448aa9117cfa6591c4e18cb32a0329a66b9cd3b7 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue, 28 Nov 2017 11:01:47 +0000
Subject: [PATCH] drm/i915: Enable hotplug polling after registering the outputs
Git-commit: 448aa9117cfa6591c4e18cb32a0329a66b9cd3b7
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900

Previously we would enable hotplug polling on the outputs immediately
upon construction. This would allow a very early hotplug event to
trigger before we had finishing setting up the driver to handle it.
Instead, move the output polling to the last step of registration, after
we have set up all handlers, including the fbdev configuration.

V2: Symmetrically turnoff the hotplug helper in unregister after the
fbdev is first synchronised then finalized. This stops a late hotplug
event being processed after the interrupts are disabled.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20171128110147.28654-1-chris@chris-wilson.co.uk
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/i915_drv.c      |   16 ++++++++++++++--
 drivers/gpu/drm/i915/intel_display.c |    5 +----
 2 files changed, 15 insertions(+), 6 deletions(-)

--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -693,8 +693,6 @@ static int i915_load_modeset_init(struct
 	/* Only enable hotplug handling once the fbdev is fully set up. */
 	intel_hpd_init(dev_priv);
 
-	drm_kms_helper_poll_init(dev);
-
 	return 0;
 
 cleanup_gem:
@@ -1255,6 +1253,13 @@ static void i915_driver_register(struct
 	 * cannot run before the connectors are registered.
 	 */
 	intel_fbdev_initial_config_async(dev);
+
+	/*
+	 * We need to coordinate the hotplugs with the asynchronous fbdev
+	 * configuration, for which we use the fbdev->async_cookie.
+	 */
+	if (INTEL_INFO(dev_priv)->num_pipes)
+		drm_kms_helper_poll_init(dev);
 }
 
 /**
@@ -1266,6 +1271,13 @@ static void i915_driver_unregister(struc
 	intel_fbdev_unregister(dev_priv);
 	intel_audio_deinit(dev_priv);
 
+	/*
+	 * After flushing the fbdev (incl. a late async config which will
+	 * have delayed queuing of a hotplug event), then flush the hotplug
+	 * events.
+	 */
+	drm_kms_helper_poll_fini(&dev_priv->drm);
+
 	intel_gpu_ips_teardown();
 	acpi_video_unregister();
 	intel_opregion_unregister(dev_priv);
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -15305,10 +15305,7 @@ static void intel_hpd_poll_fini(struct d
 	struct intel_connector *connector;
 	struct drm_connector_list_iter conn_iter;
 
-	/* First disable polling... */
-	drm_kms_helper_poll_fini(dev);
-
-	/* Then kill the work that may have been queued by hpd. */
+	/* Kill all the work that may have been queued by hpd. */
 	drm_connector_list_iter_begin(dev, &conn_iter);
 	for_each_intel_connector_iter(connector, &conn_iter) {
 		if (connector->modeset_retry_work.func)