diff mbox

[RFCv2,API,03/28] DocBook: improve STREAMON/OFF documentation.

Message ID 133a249609e30bd0c77fcc12c01b8899f3ff81d7.1347023744.git.hans.verkuil@cisco.com (mailing list archive)
State New, archived
Headers show

Commit Message

Hans Verkuil Sept. 7, 2012, 1:29 p.m. UTC 
From: Hans Verkuil <hans.verkuil@cisco.com>

Specify that STREAMON/OFF should return 0 if the stream is already
started/stopped.

The spec never specified what the correct behavior is. This ambiguity
was resolved during the 2012 Media Workshop.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 Documentation/DocBook/media/v4l/vidioc-streamon.xml |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Sylwester Nawrocki Sept. 7, 2012, 7:58 p.m. UTC | #1 
On 09/07/2012 03:29 PM, Hans Verkuil wrote:
> From: Hans Verkuil<hans.verkuil@cisco.com>
>
> Specify that STREAMON/OFF should return 0 if the stream is already
> started/stopped.
>
> The spec never specified what the correct behavior is. This ambiguity
> was resolved during the 2012 Media Workshop.
>
> Signed-off-by: Hans Verkuil<hans.verkuil@cisco.com>

Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

--

Regards,
Sylwester
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Laurent Pinchart Sept. 13, 2012, 2:17 a.m. UTC | #2 
On Friday 07 September 2012 15:29:03 Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@cisco.com>
> 
> Specify that STREAMON/OFF should return 0 if the stream is already
> started/stopped.
> 
> The spec never specified what the correct behavior is. This ambiguity
> was resolved during the 2012 Media Workshop.
> 
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
diff mbox

Patch

diff --git a/Documentation/DocBook/media/v4l/vidioc-streamon.xml b/Documentation/DocBook/media/v4l/vidioc-streamon.xml
index 81cca45..716ea15 100644
--- a/Documentation/DocBook/media/v4l/vidioc-streamon.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-streamon.xml
@@ -74,7 +74,12 @@  not transmitted yet. I/O returns to the same state as after calling
 stream type. This is the same as &v4l2-requestbuffers;
 <structfield>type</structfield>.</para>
 
-    <para>Note applications can be preempted for unknown periods right
+    <para>If <constant>VIDIOC_STREAMON</constant> is called when streaming
+is already in progress, or if <constant>VIDIOC_STREAMOFF</constant> is called
+when streaming is already stopped, then the ioctl does nothing and 0 is
+returned.</para>
+
+    <para>Note that applications can be preempted for unknown periods right
 before or after the <constant>VIDIOC_STREAMON</constant> or
 <constant>VIDIOC_STREAMOFF</constant> calls, there is no notion of
 starting or stopping "now". Buffer timestamps can be used to