drm/tilcdc Fixes and cleanups

index 79027b1..4d8f9a5 100644
@@ -246,6 +246,13 @@ void tilcdc_crtc_dpms(struct drm_crtc *crtc, int mode)
 	}
 }
 
+int tilcdc_crtc_current_dpms_state(struct drm_crtc *crtc)
+{
+	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
+
+	return tilcdc_crtc->dpms;
+}
+
 static bool tilcdc_crtc_mode_fixup(struct drm_crtc *crtc,
 		const struct drm_display_mode *mode,
 		struct drm_display_mode *adjusted_mode)

index 308e197..148b1ed 100644
@@ -598,6 +598,7 @@ static int tilcdc_pm_suspend(struct device *dev)
 	}
 
 	/* Disable the LCDC controller, to avoid locking up the PRCM */
+	priv->saved_dpms_state = tilcdc_crtc_current_dpms_state(priv->crtc);
 	tilcdc_crtc_dpms(priv->crtc, DRM_MODE_DPMS_OFF);
 
 	/* Save register state: */

@@ -628,6 +629,8 @@ static int tilcdc_pm_resume(struct device *dev)
 					     priv->saved_register[n++]);
 	}
 
+	tilcdc_crtc_dpms(priv->crtc, priv->saved_dpms_state);
+
 	drm_kms_helper_poll_enable(ddev);
 
 	return 0;

index c1de18b..3b52ce8 100644
@@ -67,6 +67,7 @@ struct tilcdc_drm_private {
 
 	/* register contents saved across suspend/resume: */
 	u32 *saved_register;
+	int saved_dpms_state;
 	bool ctx_valid;
 
 #ifdef CONFIG_CPU_FREQ

@@ -172,5 +173,6 @@ void tilcdc_crtc_set_simulate_vesa_sync(struct drm_crtc *crtc,
 int tilcdc_crtc_mode_valid(struct drm_crtc *crtc, struct drm_display_mode *mode);
 int tilcdc_crtc_max_width(struct drm_crtc *crtc);
 void tilcdc_crtc_dpms(struct drm_crtc *crtc, int mode);
+int tilcdc_crtc_current_dpms_state(struct drm_crtc *crtc);
 
 #endif /* __TILCDC_DRV_H__ */

index 4d8f9a5..1343717 100644
@@ -725,14 +725,19 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 			tilcdc_crtc->frame_intact = true;
 	}
 
-	if (priv->rev == 2) {
-		if (stat & LCDC_FRAME_DONE) {
-			tilcdc_crtc->frame_done = true;
-			wake_up(&tilcdc_crtc->frame_done_wq);
-		}
-		tilcdc_write(dev, LCDC_END_OF_INT_IND_REG, 0);
+	if (priv->rev == 1)
+		return IRQ_HANDLED;
+	/* The rest is for revision 2 only */
+
+	if (stat & LCDC_FRAME_DONE) {
+		tilcdc_crtc->frame_done = true;
+		wake_up(&tilcdc_crtc->frame_done_wq);
 	}
 
+	if (stat & LCDC_FIFO_UNDERFLOW)
+		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underfow",
+				    __func__, stat);
+
 	if (stat & LCDC_SYNC_LOST) {
 		dev_err_ratelimited(dev->dev, "%s(0x%08x): Sync lost",
 				    __func__, stat);

@@ -746,9 +751,10 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 		}
 	}
 
-	if (stat & LCDC_FIFO_UNDERFLOW)
-		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underfow",
-				    __func__, stat);
+	/* Indicate to LCDC that the interrupt service routine has
+	 * completed, see 13.3.6.1.6 in AM335x TRM.
+	 */
+	tilcdc_write(dev, LCDC_END_OF_INT_IND_REG, 0);
 
 	return IRQ_HANDLED;
 }

index 1343717..cfa1a4e 100644
@@ -113,9 +113,25 @@ static void start(struct drm_crtc *crtc)
 
 static void stop(struct drm_crtc *crtc)
 {
+	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
 	struct drm_device *dev = crtc->dev;
+	struct tilcdc_drm_private *priv = dev->dev_private;
 
+	tilcdc_crtc->frame_done = false;
 	tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
+
+	/*
+	 * if necessary wait for framedone irq which will still come
+	 * before putting things to sleep..
+	 */
+	if (priv->rev == 2) {
+		int ret = wait_event_timeout(tilcdc_crtc->frame_done_wq,
+					     tilcdc_crtc->frame_done,
+					     msecs_to_jiffies(50));
+		if (ret == 0)
+			dev_err(dev->dev, "%s: timeout waiting for framedone\n",
+				__func__);
+	}
 }
 
 static void tilcdc_crtc_destroy(struct drm_crtc *crtc)

@@ -212,22 +228,7 @@ void tilcdc_crtc_dpms(struct drm_crtc *crtc, int mode)
 		pm_runtime_get_sync(dev->dev);
 		start(crtc);
 	} else {
-		tilcdc_crtc->frame_done = false;
 		stop(crtc);
-
-		/*
-		 * if necessary wait for framedone irq which will still come
-		 * before putting things to sleep..
-		 */
-		if (priv->rev == 2) {
-			int ret = wait_event_timeout(
-					tilcdc_crtc->frame_done_wq,
-					tilcdc_crtc->frame_done,
-					msecs_to_jiffies(50));
-			if (ret == 0)
-				dev_err(dev->dev, "timeout waiting for framedone\n");
-		}
-
 		pm_runtime_put_sync(dev->dev);
 
 		if (tilcdc_crtc->next_fb) {

index 03acb4f..51811e3 100644
@@ -138,9 +138,20 @@ static int dev_match_of(struct device *dev, void *data)
 int tilcdc_get_external_components(struct device *dev,
 				   struct component_match **match)
 {
+	struct device_node *node;
 	struct device_node *ep = NULL;
 	int count = 0;
 
+	/* Avoid error print by of_graph_get_next_endpoint() if there
+	 * is no ports present.
+	 */
+	node = of_get_child_by_name(dev->of_node, "ports");
+	if (!node)
+		node = of_get_child_by_name(dev->of_node, "port");
+	if (!node)
+		return 0;
+	of_node_put(node);
+
 	while ((ep = of_graph_get_next_endpoint(dev->of_node, ep))) {
 		struct device_node *node;