drm: rcar-du: Handle event when disabling CRTCs

The driver currently handles vblank events only when updating planes on
a CRTC. The atomic update API however allows requesting an event when
disabling a CRTC. This currently leads to event objects being leaked in
the kernel and to events not being sent out. Fix it.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

drivers/gpu/drm/rcar-du/rcar_du_crtc.c

@@ -488,6 +488,13 @@ static void rcar_du_crtc_disable(struct drm_crtc *crtc)
 	rcar_du_crtc_stop(rcrtc);
 	rcar_du_crtc_put(rcrtc);
 
+	spin_lock_irq(&crtc->dev->event_lock);
+	if (crtc->state->event) {
+		drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		crtc->state->event = NULL;
+	}
+	spin_unlock_irq(&crtc->dev->event_lock);
+
 	rcrtc->outputs = 0;
 }