drm/msm/mdp4: disable vblanks when crtc is off

Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c

@@ -290,6 +290,9 @@ static void mdp4_crtc_atomic_disable(struct drm_crtc *crtc,
 	if (WARN_ON(!mdp4_crtc->enabled))
 		return;
 
+	/* Disable/save vblank irq handling before power is disabled */
+	drm_crtc_vblank_off(crtc);
+
 	mdp_irq_unregister(&mdp4_kms->base, &mdp4_crtc->err);
 	mdp4_disable(mdp4_kms);
 
@@ -308,6 +311,10 @@ static void mdp4_crtc_atomic_enable(struct drm_crtc *crtc,
 		return;
 
 	mdp4_enable(mdp4_kms);
+
+	/* Restore vblank irq handling after power is enabled */
+	drm_crtc_vblank_on(crtc);
+
 	mdp_irq_register(&mdp4_kms->base, &mdp4_crtc->err);
 
 	crtc_flush(crtc);