[Intel-gfx] [PATCH v3 3/5] drm/i915: cancel hotplug and dig_port work during suspend and unload

[Imre Deak]

Make sure these work handlers don't run after we system suspend or
unload the driver. Note that we don't cancel the handlers during runtime
suspend. That could lead to a lockup, since we take a runtime PM ref
from the handlers themselves. Fortunaltely canceling there is not needed
since the RPM ref itself provides for the needed serialization.

v2:
- fix the order of canceling dig_port_work wrt. hotplug_work (Ville)
- zero out {long,short}_hpd_port_mask and hpd_event_bits for speed
  (Ville)

Signed-off-by: Imre Deak <imre.deak at intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c      | 16 ++++++++++++++++
 drivers/gpu/drm/i915/i915_drv.h      |  1 +
 drivers/gpu/drm/i915/intel_display.c |  3 +--
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index ec96f9a..3f9c8f6 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -494,6 +494,21 @@ bool i915_semaphore_is_enabled(struct drm_device *dev)
 	return true;
 }
 
+void intel_hpd_cancel_work(struct drm_i915_private *dev_priv)
+{
+	spin_lock_irq(&dev_priv->irq_lock);
+
+	dev_priv->long_hpd_port_mask = 0;
+	dev_priv->short_hpd_port_mask = 0;
+	dev_priv->hpd_event_bits = 0;
+
+	spin_unlock_irq(&dev_priv->irq_lock);
+
+	cancel_work_sync(&dev_priv->dig_port_work);
+	cancel_work_sync(&dev_priv->hotplug_work);
+	cancel_delayed_work_sync(&dev_priv->hotplug_reenable_work);
+}
+
 static int i915_drm_freeze(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -538,6 +553,7 @@ static int i915_drm_freeze(struct drm_device *dev)
 		flush_delayed_work(&dev_priv->rps.delayed_resume_work);
 
 		intel_runtime_pm_disable_interrupts(dev);
+		intel_hpd_cancel_work(dev_priv);
 
 		intel_suspend_gt_powersave(dev);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1263aac..7a830ea 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2178,6 +2178,7 @@ extern unsigned long i915_mch_val(struct drm_i915_private *dev_priv);
 extern unsigned long i915_gfx_val(struct drm_i915_private *dev_priv);
 extern void i915_update_gfx_val(struct drm_i915_private *dev_priv);
 int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool on);
+void intel_hpd_cancel_work(struct drm_i915_private *dev_priv);
 
 extern void intel_console_resume(struct work_struct *work);
 
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index bcf8d18..d074d70 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -13103,8 +13103,7 @@ void intel_modeset_cleanup(struct drm_device *dev)
 	 * experience fancy races otherwise.
 	 */
 	drm_irq_uninstall(dev);
-	cancel_work_sync(&dev_priv->hotplug_work);
-	cancel_delayed_work_sync(&dev_priv->hotplug_reenable_work);
+	intel_hpd_cancel_work(dev_priv);
 	dev_priv->pm._irqs_disabled = true;
 
 	/*
-- 
1.8.4