drm: return if changed in drm_helper_hpd_irq_event()

The caller may want to know whether the configuration was changed, and
if an hotplug event was sent.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 5fcb9d4..55ea4ac 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -1131,14 +1131,14 @@
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_fini);
 
-void drm_helper_hpd_irq_event(struct drm_device *dev)
+bool drm_helper_hpd_irq_event(struct drm_device *dev)
 {
 	struct drm_connector *connector;
 	enum drm_connector_status old_status;
 	bool changed = false;
 
 	if (!dev->mode_config.poll_enabled)
-		return;
+		return false;
 
 	mutex_lock(&dev->mode_config.mutex);
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
@@ -1163,5 +1163,7 @@
 
 	if (changed)
 		drm_kms_helper_hotplug_event(dev);
+
+	return changed;
 }
 EXPORT_SYMBOL(drm_helper_hpd_irq_event);