diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 04e4571..3519d5f 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1160,6 +1160,8 @@ static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
 			goto out;
 		}
 		if (port->port_num >= DP_MST_LOGICAL_PORT_0) {
+			printk("**************** Carlos %s %d\n",__FUNCTION__,__LINE__);
+			
 			port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
 			drm_mode_connector_set_tile_property(port->connector);
 		}
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index ec77bd3..cfea9ea 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1217,6 +1217,11 @@ drm_do_probe_ddc_edid(void *data, u8 *buf, unsigned int block, size_t len)
 	unsigned char xfers = segment ? 3 : 2;
 	int ret, retries = 5;
 
+	if(!data){
+		printk("************* Carlos %s %d \n", __FUNCTION__,__LINE__);
+		return -1;
+	}
+
 	/*
 	 * The core I2C driver will automatically retry the transfer if the
 	 * adapter reports EAGAIN. However, we find that bit-banging transfers
@@ -1371,6 +1376,7 @@ drm_probe_ddc(struct i2c_adapter *adapter)
 {
 	unsigned char out;
 
+    //Carlos returns 0 on success
 	return (drm_do_probe_ddc_edid(adapter, &out, 0, 1) == 0);
 }
 EXPORT_SYMBOL(drm_probe_ddc);
@@ -1390,8 +1396,10 @@ struct edid *drm_get_edid(struct drm_connector *connector,
 {
 	struct edid *edid;
 
-	if (!drm_probe_ddc(adapter))
+	if (!drm_probe_ddc(adapter)){
+		printk("Carlos *********** %s %d \n",__FUNCTION__,__LINE__);
 		return NULL;
+		}
 
 	edid = drm_do_get_edid(connector, drm_do_probe_ddc_edid, adapter);
 	if (edid)