v4l2bufferpool: Queue number of allocated buffers to capture

Before we do streamon, we queue all capture buffers by calling
resurrect. When the driver supports CREATE_BUFS, this would lead
to buffers being allocated till the maximum of 32 is reached.

Instead, we now save the number of allocated buffers and queue this
amount.

2 files changed, 6 insertions, 2 deletions

diff --git a/sys/v4l2/gstv4l2bufferpool.c b/sys/v4l2/gstv4l2bufferpool.c
index d7fa9fa2e..49f222b6e 100644
--- a/sys/v4l2/gstv4l2bufferpool.c
+++ b/sys/v4l2/gstv4l2bufferpool.c
@@ -650,12 +650,14 @@ gst_v4l2_buffer_pool_streamon (GstV4l2BufferPool * pool)
     case GST_V4L2_IO_DMABUF:
     case GST_V4L2_IO_DMABUF_IMPORT:
       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. */
-        while (gst_v4l2_buffer_pool_resurrect_buffer (pool) == GST_FLOW_OK)
-          continue;
+        for (i = 0; i < pool->num_allocated; i++)
+          gst_v4l2_buffer_pool_resurrect_buffer (pool);
       }
 
       if (obj->ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0)
@@ -791,6 +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;
diff --git a/sys/v4l2/gstv4l2bufferpool.h b/sys/v4l2/gstv4l2bufferpool.h
index 285703cdb..bf0625d38 100644
--- a/sys/v4l2/gstv4l2bufferpool.h
+++ b/sys/v4l2/gstv4l2bufferpool.h
@@ -79,6 +79,7 @@ struct _GstV4l2BufferPool
   guint min_latency;         /* number of buffers we will hold */
   guint max_latency;         /* number of buffers we can hold */
   guint num_queued;          /* number of buffers queued in the driver */
+  guint num_allocated;       /* number of buffers allocated */
   guint copy_threshold;      /* when our pool runs lower, start handing out copies */
 
   gboolean streaming;