drm/i915: suspend fbdev device around suspend/hibernate

Looking at hibernate overwriting I though it looked like a cursor,
so I tracked down this missing piece to stop the cursor blink
timer. I've no idea if this is sufficient to fix the hibernate
problems people are seeing, but please test it.

Both radeon and nouveau have done this for a long time.

I've run this personally all night hib/resume cycles with no fails.

Reviewed-by: Keith Packard <keithp@keithp.com>
Reported-by: Petr Tesarik <kernel@tesarici.cz>
Reported-by: Stanislaw Gruszka <sgruszka@redhat.com>
Reported-by: Lots of misc segfaults after hibernate across the world.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=37142
Tested-by: Dave Airlie <airlied@redhat.com>
Tested-by: Bojan Smojver <bojan@rexursive.com>
Tested-by: Andreas Hartmann <andihartmann@01019freenet.de>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/i915/i915_drv.c

@@ -467,6 +467,10 @@ static int i915_drm_freeze(struct drm_device *dev)
 	/* Modeset on resume, not lid events */
 	dev_priv->modeset_on_lid = 0;
 
+	console_lock();
+	intel_fbdev_set_suspend(dev, 1);
+	console_unlock();
+
 	return 0;
 }
 
@@ -539,6 +543,9 @@ static int i915_drm_thaw(struct drm_device *dev)
 
 	dev_priv->modeset_on_lid = 0;
 
+	console_lock();
+	intel_fbdev_set_suspend(dev, 0);
+	console_unlock();
 	return error;
 }
 

drivers/gpu/drm/i915/intel_drv.h

@@ -382,7 +382,7 @@ extern int intel_framebuffer_init(struct drm_device *dev,
 				  struct drm_i915_gem_object *obj);
 extern int intel_fbdev_init(struct drm_device *dev);
 extern void intel_fbdev_fini(struct drm_device *dev);
-
+extern void intel_fbdev_set_suspend(struct drm_device *dev, int state);
 extern void intel_prepare_page_flip(struct drm_device *dev, int plane);
 extern void intel_finish_page_flip(struct drm_device *dev, int pipe);
 extern void intel_finish_page_flip_plane(struct drm_device *dev, int plane);

drivers/gpu/drm/i915/intel_fb.c

@@ -254,6 +254,16 @@ void intel_fbdev_fini(struct drm_device *dev)
 	kfree(dev_priv->fbdev);
 	dev_priv->fbdev = NULL;
 }
+
+void intel_fbdev_set_suspend(struct drm_device *dev, int state)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	if (!dev_priv->fbdev)
+		return;
+
+	fb_set_suspend(dev_priv->fbdev->helper.fbdev, state);
+}
+
 MODULE_LICENSE("GPL and additional rights");
 
 void intel_fb_output_poll_changed(struct drm_device *dev)