X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=sys%2Fv4l2%2Fgstv4l2bufferpool.c;h=49f222b6eadb94b718e59e30e6e9cb12b3706fb1;hb=fba94862a9e8205c7a83bdf15adcee5e8535f605;hp=cf8c29e078d8200b77e4e633eac528c3ff3b7016;hpb=5a6fe4ed29737aa9d9c3c18fb35d0058468c5c1d;p=platform%2Fupstream%2Fgst-plugins-good.git

diff --git a/sys/v4l2/gstv4l2bufferpool.c b/sys/v4l2/gstv4l2bufferpool.c
index cf8c29e..49f222b 100644
--- a/sys/v4l2/gstv4l2bufferpool.c
+++ b/sys/v4l2/gstv4l2bufferpool.c
@@ -610,24 +610,62 @@ wrong_config:
   }
 }
 
+static GstFlowReturn
+gst_v4l2_buffer_pool_resurrect_buffer (GstV4l2BufferPool * pool)
+{
+  GstBufferPoolAcquireParams params = { 0 };
+  GstBuffer *buffer = NULL;
+  GstFlowReturn ret;
+
+  GST_DEBUG_OBJECT (pool, "A buffer was lost, reallocating it");
+
+  /* block recursive calls to this function */
+  g_signal_handler_block (pool->vallocator, pool->group_released_handler);
+
+  params.flags =
+      (GstBufferPoolAcquireFlags) GST_V4L2_BUFFER_POOL_ACQUIRE_FLAG_RESURRECT |
+      GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT;
+  ret =
+      gst_buffer_pool_acquire_buffer (GST_BUFFER_POOL (pool), &buffer, &params);
+
+  if (ret == GST_FLOW_OK)
+    gst_buffer_unref (buffer);
+
+  g_signal_handler_unblock (pool->vallocator, pool->group_released_handler);
+
+  return ret;
+}
+
 static gboolean
 gst_v4l2_buffer_pool_streamon (GstV4l2BufferPool * pool)
 {
   GstV4l2Object *obj = pool->obj;
 
+  if (pool->streaming)
+    return TRUE;
+
   switch (obj->mode) {
     case GST_V4L2_IO_MMAP:
     case GST_V4L2_IO_USERPTR:
     case GST_V4L2_IO_DMABUF:
     case GST_V4L2_IO_DMABUF_IMPORT:
-      if (!pool->streaming) {
-        if (obj->ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0)
-          goto streamon_failed;
+      if (!V4L2_TYPE_IS_OUTPUT (pool->obj->type)) {
+        guint i;
+
+        /* For captures, we need to enqueue buffers before we start streaming,
+         * so the driver don't underflow immediatly. As we have put then back
+         * into the base class queue, resurrect them, then releasing will queue
+         * them back. */
+        for (i = 0; i < pool->num_allocated; i++)
+          gst_v4l2_buffer_pool_resurrect_buffer (pool);
+      }
 
-        pool->streaming = TRUE;
+      if (obj->ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0)
+        goto streamon_failed;
 
-        GST_DEBUG_OBJECT (pool, "Started streaming");
-      }
+      pool->streaming = TRUE;
+
+      GST_DEBUG_OBJECT (pool, "Started streaming");
       break;
     default:
       break;
@@ -643,58 +681,53 @@ streamon_failed:
   }
 }
 
+/* Call with streamlock held, or when streaming threads are down */
 static void
 gst_v4l2_buffer_pool_streamoff (GstV4l2BufferPool * pool)
 {
+  GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
   GstV4l2Object *obj = pool->obj;
+  gint i;
+
+  if (!pool->streaming)
+    return;
 
   switch (obj->mode) {
     case GST_V4L2_IO_MMAP:
     case GST_V4L2_IO_USERPTR:
     case GST_V4L2_IO_DMABUF:
     case GST_V4L2_IO_DMABUF_IMPORT:
-      if (pool->streaming) {
-        if (obj->ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0)
-          GST_WARNING_OBJECT (pool, "STREAMOFF failed with errno %d (%s)",
-              errno, g_strerror (errno));
 
-        pool->streaming = FALSE;
+      if (obj->ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0)
+        GST_WARNING_OBJECT (pool, "STREAMOFF failed with errno %d (%s)",
+            errno, g_strerror (errno));
 
-        GST_DEBUG_OBJECT (pool, "Stopped streaming");
+      pool->streaming = FALSE;
 
-        if (pool->vallocator)
-          gst_v4l2_allocator_flush (pool->vallocator);
-      }
+      GST_DEBUG_OBJECT (pool, "Stopped streaming");
+
+      if (pool->vallocator)
+        gst_v4l2_allocator_flush (pool->vallocator);
       break;
     default:
       break;
   }
-}
-
-static GstFlowReturn
-gst_v4l2_buffer_pool_resurect_buffer (GstV4l2BufferPool * pool)
-{
-  GstBufferPoolAcquireParams params = { 0 };
-  GstBuffer *buffer = NULL;
-  GstFlowReturn ret;
 
-  GST_DEBUG_OBJECT (pool, "A buffer was lost, reallocating it");
-
-  /* block recursive calls to this function */
-  g_signal_handler_block (pool->vallocator, pool->group_released_handler);
-
-  params.flags =
-      (GstBufferPoolAcquireFlags) GST_V4L2_BUFFER_POOL_ACQUIRE_FLAG_RESURRECT |
-      GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT;
-  ret =
-      gst_buffer_pool_acquire_buffer (GST_BUFFER_POOL (pool), &buffer, &params);
+  for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+    if (pool->buffers[i]) {
+      GstBuffer *buffer = pool->buffers[i];
+      GstBufferPool *bpool = GST_BUFFER_POOL (pool);
 
-  if (ret == GST_FLOW_OK)
-    gst_buffer_unref (buffer);
+      pool->buffers[i] = NULL;
 
-  g_signal_handler_unblock (pool->vallocator, pool->group_released_handler);
+      if (V4L2_TYPE_IS_OUTPUT (pool->obj->type))
+        gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
+      else                      /* Don't re-enqueue capture buffer on stop */
+        pclass->release_buffer (bpool, buffer);
 
-  return ret;
+      g_atomic_int_add (&pool->num_queued, -1);
+    }
+  }
 }
 
 static gboolean
@@ -707,10 +740,27 @@ gst_v4l2_buffer_pool_start (GstBufferPool * bpool)
   GstCaps *caps;
   guint size, min_buffers, max_buffers;
   guint max_latency, min_latency, copy_threshold = 0;
-  gboolean can_allocate = FALSE;
+  gboolean can_allocate = FALSE, ret = TRUE;
 
   GST_DEBUG_OBJECT (pool, "activating pool");
 
+  if (pool->other_pool) {
+    GstBuffer *buffer;
+
+    if (!gst_buffer_pool_set_active (pool->other_pool, TRUE))
+      goto other_pool_failed;
+
+    if (gst_buffer_pool_acquire_buffer (pool->other_pool, &buffer, NULL) !=
+        GST_FLOW_OK)
+      goto other_pool_failed;
+
+    if (!gst_v4l2_object_try_import (obj, buffer)) {
+      gst_buffer_unref (buffer);
+      goto cannot_import;
+    }
+    gst_buffer_unref (buffer);
+  }
+
   config = gst_buffer_pool_get_config (bpool);
   if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers,
           &max_buffers))
@@ -743,6 +793,7 @@ gst_v4l2_buffer_pool_start (GstBufferPool * bpool)
 
       count = gst_v4l2_allocator_start (pool->vallocator, min_buffers,
           V4L2_MEMORY_MMAP);
+      pool->num_allocated = count;
 
       if (count < GST_V4L2_MIN_BUFFERS) {
         min_buffers = count;
@@ -830,20 +881,21 @@ gst_v4l2_buffer_pool_start (GstBufferPool * bpool)
   pclass->set_config (bpool, config);
   gst_structure_free (config);
 
-  if (pool->other_pool)
-    if (!gst_buffer_pool_set_active (pool->other_pool, TRUE))
-      goto other_pool_failed;
-
   /* now, allocate the buffers: */
   if (!pclass->start (bpool))
     goto start_failed;
 
-  if (!V4L2_TYPE_IS_OUTPUT (obj->type))
+  if (!V4L2_TYPE_IS_OUTPUT (obj->type)) {
+    if (g_atomic_int_get (&pool->num_queued) < min_buffers)
+      goto queue_failed;
+
     pool->group_released_handler =
         g_signal_connect_swapped (pool->vallocator, "group-released",
-        G_CALLBACK (gst_v4l2_buffer_pool_resurect_buffer), pool);
+        G_CALLBACK (gst_v4l2_buffer_pool_resurrect_buffer), pool);
+    ret = gst_v4l2_buffer_pool_streamon (pool);
+  }
 
-  return TRUE;
+  return ret;
 
   /* ERRORS */
 wrong_config:
@@ -867,19 +919,46 @@ start_failed:
   }
 other_pool_failed:
   {
-    GST_ERROR_OBJECT (pool, "failed to active the other pool %"
+    GST_ERROR_OBJECT (pool, "failed to activate the other pool %"
         GST_PTR_FORMAT, pool->other_pool);
     return FALSE;
   }
+queue_failed:
+  {
+    GST_ERROR_OBJECT (pool, "failed to queue buffers into the capture queue");
+    return FALSE;
+  }
+cannot_import:
+  {
+    GST_ERROR_OBJECT (pool, "cannot import buffers from downstream pool");
+    return FALSE;
+  }
+}
+
+static gboolean
+gst_v4l2_buffer_pool_vallocator_stop (GstV4l2BufferPool * pool)
+{
+  GstV4l2Return vret;
+
+  if (!pool->vallocator)
+    return TRUE;
+
+  vret = gst_v4l2_allocator_stop (pool->vallocator);
+
+  if (vret == GST_V4L2_BUSY)
+    GST_WARNING_OBJECT (pool, "some buffers are still outstanding");
+
+  return (vret == GST_V4L2_OK);
 }
 
 static gboolean
 gst_v4l2_buffer_pool_stop (GstBufferPool * bpool)
 {
   GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
-  GstBufferPoolClass *pclass = GST_BUFFER_POOL_CLASS (parent_class);
   gboolean ret;
-  gint i;
+
+  if (pool->orphaned)
+    return gst_v4l2_buffer_pool_vallocator_stop (pool);
 
   GST_DEBUG_OBJECT (pool, "stopping pool");
 
@@ -897,34 +976,46 @@ gst_v4l2_buffer_pool_stop (GstBufferPool * bpool)
 
   gst_v4l2_buffer_pool_streamoff (pool);
 
-  for (i = 0; i < VIDEO_MAX_FRAME; i++) {
-    if (pool->buffers[i]) {
-      GstBuffer *buffer = pool->buffers[i];
+  ret = GST_BUFFER_POOL_CLASS (parent_class)->stop (bpool);
 
-      pool->buffers[i] = NULL;
+  if (ret)
+    ret = gst_v4l2_buffer_pool_vallocator_stop (pool);
 
-      if (V4L2_TYPE_IS_OUTPUT (pool->obj->type))
-        gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
-      else                      /* Don't re-enqueue capture buffer on stop */
-        pclass->release_buffer (bpool, buffer);
+  return ret;
+}
 
-      g_atomic_int_add (&pool->num_queued, -1);
-    }
-  }
+gboolean
+gst_v4l2_buffer_pool_orphan (GstBufferPool ** bpool)
+{
+  GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (*bpool);
+  gboolean ret;
 
-  ret = GST_BUFFER_POOL_CLASS (parent_class)->stop (bpool);
+  if (!GST_V4L2_ALLOCATOR_CAN_ORPHAN_BUFS (pool->vallocator))
+    return FALSE;
 
-  if (ret && pool->vallocator) {
-    GstV4l2Return vret;
+  if (g_getenv ("GST_V4L2_FORCE_DRAIN"))
+    return FALSE;
 
-    vret = gst_v4l2_allocator_stop (pool->vallocator);
+  GST_DEBUG_OBJECT (pool, "orphaning pool");
 
-    if (vret == GST_V4L2_BUSY)
-      GST_WARNING_OBJECT (pool, "some buffers are still outstanding");
+  gst_buffer_pool_set_active (*bpool, FALSE);
+  /*
+   * If the buffer pool has outstanding buffers, it will not be stopped
+   * by the base class when set inactive. Stop it manually and mark it
+   * as orphaned
+   */
+  ret = gst_v4l2_buffer_pool_stop (*bpool);
+  if (!ret)
+    ret = gst_v4l2_allocator_orphan (pool->vallocator);
 
-    ret = (vret == GST_V4L2_OK);
-  }
+  if (!ret)
+    goto orphan_failed;
+
+  pool->orphaned = TRUE;
+  gst_object_unref (*bpool);
+  *bpool = NULL;
 
+orphan_failed:
   return ret;
 }
 
@@ -950,89 +1041,53 @@ static void
 gst_v4l2_buffer_pool_flush_stop (GstBufferPool * bpool)
 {
   GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
-  GstV4l2Object *obj = pool->obj;
-  GstBuffer *buffers[VIDEO_MAX_FRAME];
-  gint i;
 
   GST_DEBUG_OBJECT (pool, "stop flushing");
 
-  /* If we haven't started streaming yet, simply call streamon */
-  if (!pool->streaming)
-    goto streamon;
-
   if (pool->other_pool)
     gst_buffer_pool_set_flushing (pool->other_pool, FALSE);
 
-  GST_OBJECT_LOCK (pool);
-  gst_v4l2_buffer_pool_streamoff (pool);
-  /* Remember buffers to re-enqueue */
-  memcpy (buffers, pool->buffers, sizeof (buffers));
-  memset (pool->buffers, 0, sizeof (pool->buffers));
-  GST_OBJECT_UNLOCK (pool);
-
-  /* Reset our state */
-  switch (obj->mode) {
-    case GST_V4L2_IO_RW:
-      break;
-    case GST_V4L2_IO_MMAP:
-    case GST_V4L2_IO_USERPTR:
-    case GST_V4L2_IO_DMABUF:
-    case GST_V4L2_IO_DMABUF_IMPORT:
-    {
-      for (i = 0; i < VIDEO_MAX_FRAME; i++) {
-        /* Re-enqueue buffers */
-        if (buffers[i]) {
-          GstBufferPool *bpool = (GstBufferPool *) pool;
-          GstBuffer *buffer = buffers[i];
-
-          /* Remove qdata, this will unmap any map data in
-           * userptr/dmabuf-import */
-          gst_mini_object_set_qdata (GST_MINI_OBJECT (buffer),
-              GST_V4L2_IMPORT_QUARK, NULL, NULL);
-
-          if (buffer->pool == NULL)
-            gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
-
-          g_atomic_int_add (&pool->num_queued, -1);
-        }
-      }
-
-      break;
-    }
-    default:
-      g_assert_not_reached ();
-      break;
-  }
-
-streamon:
-  /* Start streaming on capture device only */
-  if (!V4L2_TYPE_IS_OUTPUT (obj->type))
-    gst_v4l2_buffer_pool_streamon (pool);
-
   gst_poll_set_flushing (pool->poll, FALSE);
 }
 
 static GstFlowReturn
-gst_v4l2_buffer_pool_poll (GstV4l2BufferPool * pool)
+gst_v4l2_buffer_pool_poll (GstV4l2BufferPool * pool, gboolean wait)
 {
   gint ret;
+  GstClockTime timeout;
+
+  if (wait)
+    timeout = GST_CLOCK_TIME_NONE;
+  else
+    timeout = 0;
 
   /* In RW mode there is no queue, hence no need to wait while the queue is
    * empty */
   if (pool->obj->mode != GST_V4L2_IO_RW) {
     GST_OBJECT_LOCK (pool);
+
+    if (!wait && pool->empty) {
+      GST_OBJECT_UNLOCK (pool);
+      goto no_buffers;
+    }
+
     while (pool->empty)
       g_cond_wait (&pool->empty_cond, GST_OBJECT_GET_LOCK (pool));
+
     GST_OBJECT_UNLOCK (pool);
   }
 
-  if (!pool->can_poll_device)
-    goto done;
+  if (!pool->can_poll_device) {
+    if (wait)
+      goto done;
+    else
+      goto no_buffers;
+  }
 
   GST_LOG_OBJECT (pool, "polling device");
 
 again:
-  ret = gst_poll_wait (pool->poll, GST_CLOCK_TIME_NONE);
+  ret = gst_poll_wait (pool->poll, timeout);
   if (G_UNLIKELY (ret < 0)) {
     switch (errno) {
       case EBUSY:
@@ -1054,6 +1109,9 @@ again:
   if (gst_poll_fd_has_error (pool->poll, &pool->pollfd))
     goto select_error;
 
+  if (ret == 0)
+    goto no_buffers;
+
 done:
   return GST_FLOW_OK;
 
@@ -1069,22 +1127,18 @@ select_error:
         ("poll error %d: %s (%d)", ret, g_strerror (errno), errno));
     return GST_FLOW_ERROR;
   }
+no_buffers:
+  return GST_FLOW_CUSTOM_SUCCESS;
 }
 
 static GstFlowReturn
-gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf)
+gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf,
+    GstV4l2MemoryGroup * group)
 {
-  GstV4l2MemoryGroup *group = NULL;
   const GstV4l2Object *obj = pool->obj;
   GstClockTime timestamp;
   gint index;
 
-  if (!gst_v4l2_is_buffer_valid (buf, &group)) {
-    GST_LOG_OBJECT (pool, "unref copied/invalid buffer %p", buf);
-    gst_buffer_unref (buf);
-    return GST_FLOW_OK;
-  }
-
   index = group->buffer.index;
 
   if (pool->buffers[index] != NULL)
@@ -1150,18 +1204,26 @@ queue_failed:
 }
 
 static GstFlowReturn
-gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
+gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer,
+    gboolean wait)
 {
   GstFlowReturn res;
-  GstBuffer *outbuf;
+  GstBuffer *outbuf = NULL;
   GstV4l2Object *obj = pool->obj;
   GstClockTime timestamp;
   GstV4l2MemoryGroup *group;
+  GstVideoMeta *vmeta;
+  gsize size;
   gint i;
 
-  if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK)
+  if ((res = gst_v4l2_buffer_pool_poll (pool, wait)) < GST_FLOW_OK)
     goto poll_failed;
 
+  if (res == GST_FLOW_CUSTOM_SUCCESS) {
+    GST_LOG_OBJECT (pool, "nothing to dequeue");
+    goto done;
+  }
+
   GST_LOG_OBJECT (pool, "dequeueing a buffer");
 
   res = gst_v4l2_allocator_dqbuf (pool->vallocator, &group);
@@ -1187,7 +1249,8 @@ gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
 
   timestamp = GST_TIMEVAL_TO_TIME (group->buffer.timestamp);
 
-#ifndef GST_DISABLE_GST_DEBUG
+  size = 0;
+  vmeta = gst_buffer_get_video_meta (outbuf);
   for (i = 0; i < group->n_mem; i++) {
     GST_LOG_OBJECT (pool,
         "dequeued buffer %p seq:%d (ix=%d), mem %p used %d, plane=%d, flags %08x, ts %"
@@ -1195,8 +1258,12 @@ gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
         group->buffer.sequence, group->buffer.index, group->mem[i],
         group->planes[i].bytesused, i, group->buffer.flags,
         GST_TIME_ARGS (timestamp), pool->num_queued, outbuf);
+
+    if (vmeta) {
+      vmeta->offset[i] = size;
+      size += gst_memory_get_sizes (group->mem[i], NULL, NULL);
+    }
   }
-#endif
 
   /* Ignore timestamp and field for OUTPUT device */
   if (V4L2_TYPE_IS_OUTPUT (obj->type))
@@ -1264,7 +1331,10 @@ gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
   }
 
   if (GST_VIDEO_INFO_FORMAT (&obj->info) == GST_VIDEO_FORMAT_ENCODED) {
-    if (group->buffer.flags & V4L2_BUF_FLAG_KEYFRAME)
+    if ((group->buffer.flags & V4L2_BUF_FLAG_KEYFRAME) ||
+        GST_V4L2_PIXELFORMAT (obj) == V4L2_PIX_FMT_MJPEG ||
+        GST_V4L2_PIXELFORMAT (obj) == V4L2_PIX_FMT_JPEG ||
+        GST_V4L2_PIXELFORMAT (obj) == V4L2_PIX_FMT_PJPG)
       GST_BUFFER_FLAG_UNSET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
     else
       GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DELTA_UNIT);
@@ -1280,7 +1350,7 @@ gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
 done:
   *buffer = outbuf;
 
-  return GST_FLOW_OK;
+  return res;
 
   /* ERRORS */
 poll_failed:
@@ -1315,7 +1385,7 @@ gst_v4l2_buffer_pool_acquire_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
 
   GST_DEBUG_OBJECT (pool, "acquire");
 
-  /* If this is being called to resurect a lost buffer */
+  /* If this is being called to resurrect a lost buffer */
   if (params && params->flags & GST_V4L2_BUFFER_POOL_ACQUIRE_FLAG_RESURRECT) {
     ret = pclass->acquire_buffer (bpool, buffer, params);
     goto done;
@@ -1340,7 +1410,7 @@ gst_v4l2_buffer_pool_acquire_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
           /* just dequeue a buffer, we basically use the queue of v4l2 as the
            * storage for our buffers. This function does poll first so we can
            * interrupt it fine. */
-          ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer);
+          ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer, TRUE);
           break;
         }
         default:
@@ -1393,6 +1463,14 @@ gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer)
 
   GST_DEBUG_OBJECT (pool, "release buffer %p", buffer);
 
+  /* If the buffer's pool has been orphaned, dispose of it so that
+   * the pool resources can be freed */
+  if (pool->orphaned) {
+    GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
+    pclass->release_buffer (bpool, buffer);
+    return;
+  }
+
   switch (obj->type) {
     case V4L2_BUF_TYPE_VIDEO_CAPTURE:
     case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
@@ -1411,11 +1489,14 @@ gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer)
         {
           GstV4l2MemoryGroup *group;
           if (gst_v4l2_is_buffer_valid (buffer, &group)) {
+            GstFlowReturn ret = GST_FLOW_OK;
+
             gst_v4l2_allocator_reset_group (pool->vallocator, group);
             /* queue back in the device */
             if (pool->other_pool)
-              gst_v4l2_buffer_pool_prepare_buffer (pool, buffer, NULL);
-            if (gst_v4l2_buffer_pool_qbuf (pool, buffer) != GST_FLOW_OK)
+              ret = gst_v4l2_buffer_pool_prepare_buffer (pool, buffer, NULL);
+            if (ret != GST_FLOW_OK ||
+                gst_v4l2_buffer_pool_qbuf (pool, buffer, group) != GST_FLOW_OK)
               pclass->release_buffer (bpool, buffer);
           } else {
             /* Simply release invalide/modified buffer, the allocator will
@@ -1540,6 +1621,7 @@ gst_v4l2_buffer_pool_init (GstV4l2BufferPool * pool)
   pool->can_poll_device = TRUE;
   g_cond_init (&pool->empty_cond);
   pool->empty = TRUE;
+  pool->orphaned = FALSE;
 }
 
 static void
@@ -1652,7 +1734,7 @@ gst_v4l2_do_read (GstV4l2BufferPool * pool, GstBuffer * buf)
   gst_buffer_map (buf, &map, GST_MAP_WRITE);
 
   do {
-    if ((res = gst_v4l2_buffer_pool_poll (pool)) != GST_FLOW_OK)
+    if ((res = gst_v4l2_buffer_pool_poll (pool, TRUE)) != GST_FLOW_OK)
       goto poll_error;
 
     amount = obj->read (obj->video_fd, map.data, toread);
@@ -1740,20 +1822,13 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
             guint num_queued;
             gsize size = gst_buffer_get_size (*buf);
 
-            if (size == 0) {
-              if (GST_BUFFER_FLAG_IS_SET (*buf, GST_BUFFER_FLAG_CORRUPTED))
-                goto buffer_corrupted;
-              else
-                goto eos;
-            }
+            /* Legacy M2M devices return empty buffer when drained */
+            if (size == 0 && GST_V4L2_IS_M2M (obj->device_caps))
+              goto eos;
 
-            /* verify that buffer contains a full frame for raw video */
-            if (GST_VIDEO_INFO_FORMAT (&obj->info) != GST_VIDEO_FORMAT_ENCODED
-                && size < GST_VIDEO_INFO_SIZE (&obj->info)) {
-              GST_WARNING_OBJECT (pool, "Invalid buffer size, this is likely "
-                  "due to a bug in your driver, dropping");
-              goto buffer_corrupted;
-            }
+            if (GST_VIDEO_INFO_FORMAT (&pool->caps_info) !=
+                GST_VIDEO_FORMAT_ENCODED && size < pool->size)
+              goto buffer_truncated;
 
             num_queued = g_atomic_int_get (&pool->num_queued);
             GST_TRACE_OBJECT (pool, "Only %i buffer left in the capture queue.",
@@ -1762,7 +1837,7 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
             /* If we have no more buffer, and can allocate it time to do so */
             if (num_queued == 0) {
               if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) {
-                ret = gst_v4l2_buffer_pool_resurect_buffer (pool);
+                ret = gst_v4l2_buffer_pool_resurrect_buffer (pool);
                 if (ret == GST_FLOW_OK)
                   goto done;
               }
@@ -1773,7 +1848,7 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
               GstBuffer *copy;
 
               if (GST_V4L2_ALLOCATOR_CAN_ALLOCATE (pool->vallocator, MMAP)) {
-                ret = gst_v4l2_buffer_pool_resurect_buffer (pool);
+                ret = gst_v4l2_buffer_pool_resurrect_buffer (pool);
                 if (ret == GST_FLOW_OK)
                   goto done;
               }
@@ -1794,19 +1869,16 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
           }
 
           /* buffer not from our pool, grab a frame and copy it into the target */
-          if ((ret = gst_v4l2_buffer_pool_dqbuf (pool, &tmp)) != GST_FLOW_OK)
+          if ((ret = gst_v4l2_buffer_pool_dqbuf (pool, &tmp, TRUE))
+              != GST_FLOW_OK)
             goto done;
 
           /* An empty buffer on capture indicates the end of stream */
           if (gst_buffer_get_size (tmp) == 0) {
-            gboolean corrupted = GST_BUFFER_FLAG_IS_SET (tmp,
-                GST_BUFFER_FLAG_CORRUPTED);
-
             gst_v4l2_buffer_pool_release_buffer (bpool, tmp);
 
-            if (corrupted)
-              goto buffer_corrupted;
-            else
+            /* Legacy M2M devices return empty buffer when drained */
+            if (GST_V4L2_IS_M2M (obj->device_caps))
               goto eos;
           }
 
@@ -1823,12 +1895,20 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
         case GST_V4L2_IO_USERPTR:
         {
           struct UserPtrData *data;
+          GstBuffer *tmp;
 
           /* Replace our buffer with downstream allocated buffer */
           data = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf),
               GST_V4L2_IMPORT_QUARK);
-          gst_buffer_replace (buf, data->buffer);
+          tmp = gst_buffer_ref (data->buffer);
           _unmap_userptr_frame (data);
+
+          /* Now tmp is writable, copy the flags and timestamp */
+          gst_buffer_copy_into (tmp, *buf,
+              GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
+
+          gst_buffer_replace (buf, tmp);
+          gst_buffer_unref (tmp);
           break;
         }
 
@@ -1839,6 +1919,10 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
           /* Replace our buffer with downstream allocated buffer */
           tmp = gst_mini_object_steal_qdata (GST_MINI_OBJECT (*buf),
               GST_V4L2_IMPORT_QUARK);
+
+          gst_buffer_copy_into (tmp, *buf,
+              GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
+
           gst_buffer_replace (buf, tmp);
           gst_buffer_unref (tmp);
           break;
@@ -1865,6 +1949,7 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
         case GST_V4L2_IO_MMAP:
         {
           GstBuffer *to_queue = NULL;
+          GstBuffer *buffer;
           GstV4l2MemoryGroup *group;
           gint index;
 
@@ -1905,9 +1990,13 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
               gst_buffer_unref (to_queue);
               goto prepare_failed;
             }
+
+            /* retreive the group */
+            gst_v4l2_is_buffer_valid (to_queue, &group);
           }
 
-          if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue)) != GST_FLOW_OK)
+          if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue, group))
+              != GST_FLOW_OK)
             goto queue_failed;
 
           /* if we are not streaming yet (this is the first buffer, start
@@ -1935,15 +2024,21 @@ gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer ** buf)
            * otherwise the pool will think it is outstanding and will refuse to stop. */
           gst_buffer_unref (to_queue);
 
+          /* release as many buffer as possible */
+          while (gst_v4l2_buffer_pool_dqbuf (pool, &buffer, FALSE) ==
+              GST_FLOW_OK) {
+            if (buffer->pool == NULL)
+              gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
+          }
+
           if (g_atomic_int_get (&pool->num_queued) >= pool->min_latency) {
-            GstBuffer *out;
             /* all buffers are queued, try to dequeue one and release it back
              * into the pool so that _acquire can get to it again. */
-            ret = gst_v4l2_buffer_pool_dqbuf (pool, &out);
-            if (ret == GST_FLOW_OK && out->pool == NULL)
+            ret = gst_v4l2_buffer_pool_dqbuf (pool, &buffer, TRUE);
+            if (ret == GST_FLOW_OK && buffer->pool == NULL)
               /* release the rendered buffer back into the pool. This wakes up any
                * thread waiting for a buffer in _acquire(). */
-              gst_v4l2_buffer_pool_release_buffer (bpool, out);
+              gst_v4l2_buffer_pool_release_buffer (bpool, buffer);
           }
           break;
         }
@@ -1965,9 +2060,10 @@ copy_failed:
     GST_ERROR_OBJECT (pool, "failed to copy buffer");
     return ret;
   }
-buffer_corrupted:
+buffer_truncated:
   {
-    GST_WARNING_OBJECT (pool, "Dropping corrupted buffer without payload");
+    GST_WARNING_OBJECT (pool,
+        "Dropping truncated buffer, this is likely a driver bug.");
     gst_buffer_unref (*buf);
     *buf = NULL;
     return GST_V4L2_FLOW_CORRUPTED_BUFFER;
@@ -2023,3 +2119,17 @@ gst_v4l2_buffer_pool_copy_at_threshold (GstV4l2BufferPool * pool, gboolean copy)
   pool->enable_copy_threshold = copy;
   GST_OBJECT_UNLOCK (pool);
 }
+
+gboolean
+gst_v4l2_buffer_pool_flush (GstBufferPool * bpool)
+{
+  GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
+  gboolean ret = TRUE;
+
+  gst_v4l2_buffer_pool_streamoff (pool);
+
+  if (!V4L2_TYPE_IS_OUTPUT (pool->obj->type))
+    ret = gst_v4l2_buffer_pool_streamon (pool);
+
+  return ret;
+}