From patchwork Thu Feb 20 19:42:56 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 3689291 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4CDA7BF13A for ; Thu, 20 Feb 2014 19:40:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6AF7420173 for ; Thu, 20 Feb 2014 19:40:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4ABED20155 for ; Thu, 20 Feb 2014 19:40:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752412AbaBTTky (ORCPT ); Thu, 20 Feb 2014 14:40:54 -0500 Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:38410 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751363AbaBTTky (ORCPT ); Thu, 20 Feb 2014 14:40:54 -0500 Received: from lanttu.localdomain (salottisipuli.retiisi.org.uk [IPv6:2001:1bc8:102:7fc9::83:2]) by hillosipuli.retiisi.org.uk (Postfix) with ESMTP id 509976008E; Thu, 20 Feb 2014 21:40:52 +0200 (EET) From: Sakari Ailus To: linux-media@vger.kernel.org, hverkuil@xs4all.nl Cc: laurent.pinchart@ideasonboard.com, k.debski@samsung.com Subject: [PATCH v5.1 7/7] v4l: Document timestamp buffer flag behaviour Date: Thu, 20 Feb 2014 21:42:56 +0200 Message-Id: <1392925376-20562-1-git-send-email-sakari.ailus@iki.fi> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <20140217233305.GY15635@valkosipuli.retiisi.org.uk> References: <20140217233305.GY15635@valkosipuli.retiisi.org.uk> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 Acked-by: Hans Verkuil --- since v5: - Clarify timestamp source flag behaviour. 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 22b87bc..a69e12a 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. The driver + decides at which part of the frame and with which clock the + timestamp is taken. Please see flags in the masks + V4L2_BUF_FLAG_TIMESTAMP_MASK and + V4L2_BUF_FLAG_TSTAMP_SRC_MASK in . These flags are always valid and constant + across all buffers during the whole video stream. Changes in these + flags may take place as a side effect of &VIDIOC-S-INPUT; or + &VIDIOC-S-OUTPUT; however. + struct <structname>v4l2_buffer</structname>