kmssink plugin bind vaild buffer when enable drm pipeline.

Signed-off-by: Leo Lu <leo.lu@starfivetech.com>

diff -pruN a/sys/kms/gstkmssink.c b/sys/kms/gstkmssink.c
--- a/sys/kms/gstkmssink.c	2023-05-08 11:08:39.273491472 +0800
+++ b/sys/kms/gstkmssink.c	2023-05-08 10:56:22.825058287 +0800
@@ -426,14 +426,13 @@ ensure_kms_allocator (GstKMSSink * self)
 }
 
 static gboolean
-configure_mode_setting (GstKMSSink * self, GstVideoInfo * vinfo)
+configure_mode_setting (GstKMSSink * self, GstVideoInfo * vinfo, guint32 fb_id)
 {
   gboolean ret;
   drmModeConnector *conn;
   int err;
   gint i;
   drmModeModeInfo *mode;
-  guint32 fb_id;
   GstKMSMemory *kmsmem;
 
   ret = FALSE;
@@ -450,7 +449,6 @@ configure_mode_setting (GstKMSSink * sel
   kmsmem = (GstKMSMemory *) gst_kms_allocator_bo_alloc (self->allocator, vinfo);
   if (!kmsmem)
     goto bo_failed;
-  fb_id = kmsmem->fb_id;
 
   conn = drmModeGetConnector (self->fd, self->conn_id);
   if (!conn)
@@ -1150,8 +1148,6 @@ gst_kms_sink_set_caps (GstBaseSink * bsi
     self->pool = NULL;
   }
 
-  if (self->modesetting_enabled && !configure_mode_setting (self, &vinfo))
-    goto modesetting_failed;
 
   GST_OBJECT_LOCK (self);
   if (self->reconfigure) {
@@ -1185,13 +1181,6 @@ no_disp_ratio:
     return FALSE;
   }
 
-modesetting_failed:
-  {
-    GST_ELEMENT_ERROR (self, CORE, NEGOTIATION, (NULL),
-        ("failed to configure video mode"));
-    return FALSE;
-  }
-
 }
 
 static gboolean
@@ -1578,6 +1567,7 @@ gst_kms_sink_show_frame (GstVideoSink *
   GstVideoRectangle dst = { 0, };
   GstVideoRectangle result;
   GstFlowReturn res;
+  static bool configure_flag = FALSE;
 
   self = GST_KMS_SINK (vsink);
 
@@ -1609,6 +1599,11 @@ gst_kms_sink_show_frame (GstVideoSink *
   GST_OBJECT_LOCK (self);
   if (self->modesetting_enabled) {
     self->buffer_id = fb_id;
+    if ( !configure_flag && !configure_mode_setting (self, &self->vinfo, self->buffer_id)) {
+        configure_flag = TRUE;
+        goto modesetting_failed;
+      }
+    configure_flag = TRUE;
     goto sync_frame;
   }
 
@@ -1724,6 +1719,13 @@ no_disp_ratio:
         ("Error calculating the output display ratio of the video."));
     goto bail;
   }
+
+modesetting_failed:
+  {
+    GST_ELEMENT_ERROR (self, CORE, NEGOTIATION, (NULL),
+        ("failed to configure video mode"));
+    return GST_FLOW_ERROR;
+  }
 }
 
 static void