X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Documentation%2FDocBook%2Fv4l%2Fvidioc-qbuf.xml;h=ab691ebf3b9373969b95a2af7cac8d84663fc35a;hb=8b108c609adefd98577c35f0a41497a610041a6c;hp=b843bd7b389735725bd7d68954560509efe5cc41;hpb=c6b9e73f2fee8bb86058f296de808b326473456b;p=pandora-kernel.git diff --git a/Documentation/DocBook/v4l/vidioc-qbuf.xml b/Documentation/DocBook/v4l/vidioc-qbuf.xml index b843bd7b3897..ab691ebf3b93 100644 --- a/Documentation/DocBook/v4l/vidioc-qbuf.xml +++ b/Documentation/DocBook/v4l/vidioc-qbuf.xml @@ -111,7 +111,11 @@ from the driver's outgoing queue. They just set the and reserved fields of a &v4l2-buffer; as above, when VIDIOC_DQBUF is called with a pointer to this structure the driver fills the -remaining fields or returns an error code. +remaining fields or returns an error code. The driver may also set +V4L2_BUF_FLAG_ERROR in the flags +field. It indicates a non-critical (recoverable) streaming error. In such case +the application may continue as normal, but should be aware that data in the +dequeued buffer might be corrupted. By default VIDIOC_DQBUF blocks when no buffer is in the outgoing queue. When the @@ -158,7 +162,13 @@ enqueue a user pointer buffer. VIDIOC_DQBUF failed due to an internal error. Can also indicate temporary problems like signal loss. Note the driver might dequeue an (empty) buffer despite -returning an error, or even stop capturing. +returning an error, or even stop capturing. Reusing such buffer may be unsafe +though and its details (e.g. index) may not be +returned either. It is recommended that drivers indicate recoverable errors +by setting the V4L2_BUF_FLAG_ERROR and returning 0 instead. +In that case the application should be able to safely reuse the buffer and +continue streaming. +