drm/i915: Unregister ACPI video driver when exiting

The i915 DRM triggers registration of the ACPI video driver on load. It
should unregister it at unload in order to avoid generating backtraces on
being reloaded.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index a000cf0..2726143 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1232,7 +1232,7 @@
 	if (dev_priv->regs != NULL)
 		iounmap(dev_priv->regs);
 
-	intel_opregion_free(dev);
+	intel_opregion_free(dev, 0);
 
 	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
 		intel_modeset_cleanup(dev);
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 6503e22..98560e1 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -77,7 +77,7 @@
 		drm_irq_uninstall(dev);
 	}
 
-	intel_opregion_free(dev);
+	intel_opregion_free(dev, 1);
 
 	if (state.event == PM_EVENT_SUSPEND) {
 		/* Shut down the device */
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 473a8f7..d7471fe 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -674,12 +674,12 @@
 #ifdef CONFIG_ACPI
 /* i915_opregion.c */
 extern int intel_opregion_init(struct drm_device *dev, int resume);
-extern void intel_opregion_free(struct drm_device *dev);
+extern void intel_opregion_free(struct drm_device *dev, int suspend);
 extern void opregion_asle_intr(struct drm_device *dev);
 extern void opregion_enable_asle(struct drm_device *dev);
 #else
 static inline int intel_opregion_init(struct drm_device *dev, int resume) { return 0; }
-static inline void intel_opregion_free(struct drm_device *dev) { return; }
+static inline void intel_opregion_free(struct drm_device *dev, int suspend) { return; }
 static inline void opregion_asle_intr(struct drm_device *dev) { return; }
 static inline void opregion_enable_asle(struct drm_device *dev) { return; }
 #endif
diff --git a/drivers/gpu/drm/i915/i915_opregion.c b/drivers/gpu/drm/i915/i915_opregion.c
index 8dc1fd3..3eceefe 100644
--- a/drivers/gpu/drm/i915/i915_opregion.c
+++ b/drivers/gpu/drm/i915/i915_opregion.c
@@ -409,7 +409,7 @@
 	return err;
 }
 
-void intel_opregion_free(struct drm_device *dev)
+void intel_opregion_free(struct drm_device *dev, int suspend)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_opregion *opregion = &dev_priv->opregion;
@@ -417,6 +417,9 @@
 	if (!opregion->enabled)
 		return;
 
+	if (!suspend)
+		acpi_video_exit();
+
 	opregion->acpi->drdy = 0;
 
 	system_opregion = NULL;