From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:48809 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752718AbaBPRui (ORCPT ); Sun, 16 Feb 2014 12:50:38 -0500 Date: Sun, 16 Feb 2014 19:50:32 +0200 From: Sakari Ailus To: Hans Verkuil Cc: linux-media@vger.kernel.org, laurent.pinchart@ideasonboard.com, k.debski@samsung.com Subject: Re: [PATCH v5 7/7] v4l: Document timestamp buffer flag behaviour Message-ID: <20140216175032.GR15635@valkosipuli.retiisi.org.uk> References: <1392497585-5084-1-git-send-email-sakari.ailus@iki.fi> <1392497585-5084-8-git-send-email-sakari.ailus@iki.fi> <52FFD60B.4080308@xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52FFD60B.4080308@xs4all.nl> Sender: linux-media-owner@vger.kernel.org List-ID: Hi Hans, On Sat, Feb 15, 2014 at 10:03:07PM +0100, Hans Verkuil wrote: > On 02/15/2014 09:53 PM, Sakari Ailus wrote: > > Timestamp buffer flags are constant at the moment. Document them so that 1) > > they're always valid and 2) not changed by the drivers. This leaves room to > > extend the functionality later on if needed. > > > > Signed-off-by: Sakari Ailus > > --- > > Documentation/DocBook/media/v4l/io.xml | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml > > index fbd0c6e..4f76565 100644 > > --- a/Documentation/DocBook/media/v4l/io.xml > > +++ b/Documentation/DocBook/media/v4l/io.xml > > @@ -653,6 +653,16 @@ plane, are stored in struct v4l2_plane instead. > > In that case, struct v4l2_buffer contains an array of > > plane structures. > > > > + Dequeued video buffers come with timestamps. These > > + timestamps can be taken from different clocks and at different > > + part of the frame, depending on the driver. Please see flags in > > s/part/parts/ > > But I think I would write it somewhat differently: > > "The driver decides at which part of the frame and with which clock > the timestamp is taken." I'll fix both for the next version. > > + the masks V4L2_BUF_FLAG_TIMESTAMP_MASK and > > + V4L2_BUF_FLAG_TSTAMP_SRC_MASK in > + linkend="buffer-flags">. These flags are guaranteed to be always > > + valid and will not be changed by the driver autonomously. Changes > > + in these flags may take place due as a side effect of > > s/due// -- Regards, Sakari Ailus e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk