From patchwork Sun Feb 22 17:39:33 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: wk X-Patchwork-Id: 8324 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n1MHddTJ019846 for ; Sun, 22 Feb 2009 17:39:40 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbZBVRji (ORCPT ); Sun, 22 Feb 2009 12:39:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751146AbZBVRji (ORCPT ); Sun, 22 Feb 2009 12:39:38 -0500 Received: from mail.gmx.net ([213.165.64.20]:41478 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751197AbZBVRjh (ORCPT ); Sun, 22 Feb 2009 12:39:37 -0500 Received: (qmail invoked by alias); 22 Feb 2009 17:39:34 -0000 Received: from p54BDF0DD.dip.t-dialin.net (EHLO [192.168.6.106]) [84.189.240.221] by mail.gmx.net (mp061) with SMTP; 22 Feb 2009 18:39:34 +0100 X-Authenticated: #4875094 X-Provags-ID: V01U2FsdGVkX1/kd09ILZjkm24civDE9F+B7mdsE2NysTk3rEi0Q8 QdUQj6x8MCzP9j Message-ID: <49A18DD5.40206@gmx.de> Date: Sun, 22 Feb 2009 18:39:33 +0100 From: wk User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 To: linux-media@vger.kernel.org Subject: [PATCH] dvb-api: update documentation, chapter1 X-Y-GMX-Trusted: 0 X-FuHaFi: 0.84,0.45 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Since dvb-api doc is still outdated by six years... The following patch changes dvbapi.pdf as following: diff -Nrup v4l-dvb-359d95e1d541/dvb-spec/dvbapi/dvbapi.tex v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/dvbapi.tex --- v4l-dvb-359d95e1d541/dvb-spec/dvbapi/dvbapi.tex 2009-02-22 17:07:48.123742503 +0100 +++ v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/dvbapi.tex 2009-02-21 17:33:29.557033066 +0100 @@ -1,4 +1,4 @@ -\documentclass[a4paper,10pt]{book} +\documentclass[a4paper,10pt,oneside]{book} \usepackage[dvips,colorlinks=true]{hyperref} \usepackage{times} diff -Nrup v4l-dvb-359d95e1d541/dvb-spec/dvbapi/intro.tex v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/intro.tex --- v4l-dvb-359d95e1d541/dvb-spec/dvbapi/intro.tex 2009-02-18 13:49:37.000000000 +0100 +++ v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/intro.tex 2009-02-22 16:03:12.610230293 +0100 @@ -7,36 +7,73 @@ The reader of this document is required to have some knowledge in the area of digital video broadcasting (DVB) and should be familiar with part I of the MPEG2 specification ISO/IEC 13818 (aka ITU-T H.222), -i.e you should know what a program/transport stream (PS/TS) is and what is -meant by a packetized elementary stream (PES) or an I-frame. - -Various DVB standards documents are available from -\texttt{http://www.dvb.org/} and/or \texttt{http://www.etsi.org/}. +i.e you should know what a program stream or transport stream (PS/TS) is +and what is meant by a packetized elementary stream (PES) or an I-frame. +Various DVB standards documents are available from \texttt{http://www.dvb.org/} +and/or \texttt{http://www.etsi.org/}. It is also necessary to know how to access unix/linux devices and how to use ioctl calls. This also includes the knowledge of C or C++. +The goal of this API is to provide a consistent abstraction layer for +different digital TV hardware, allowing software applications to be +developed without hardware details as well as serving as driver +developers reference. + +For this API documentation applies an even/odd versioning scheme, stating +unstable or stable versions of that API. Only stable API versions should +be used for developing drivers and applications. +\newpage \section{History} -The first API for DVB cards we used at Convergence in late 1999 -was an extension of the Video4Linux API which was primarily +The first API for DVB cards was used at Convergence in late 1999 +as an extension of the Video4Linux API which was primarily developed for frame grabber cards. + + As such it was not really well suited to be used for DVB cards and their new features like recording MPEG streams and filtering several section and PES data streams at the same time. -In early 2000, we were approached by Nokia with a proposal for a new + +In early 2000, Convergence was approached by Nokia with a proposal for a new standard Linux DVB API. As a commitment to the development of terminals based on open standards, Nokia and Convergence made it available to all Linux developers and published it on \texttt{http://www.linuxtv.org/} in September 2000. -Convergence is the maintainer of the Linux DVB API. -Together with the LinuxTV community (i.e. you, the reader of this document), -the Linux DVB API will be constantly reviewed and improved. -With the Linux driver for the Siemens/Hauppauge DVB PCI card Convergence -provides a first implementation of the Linux DVB API. +In 2003 Convergence and Toshiba Electronics Europe GmbH started the development +of +\href {http://www.linuxtv.org/downloads/linux-dvb-api-v4/linux-dvb-api-v4-0-3.pdf}{DVB API Version 4} +with public discussion on the linux-dvb mailing list. The goal was a complete +new API, reflecting that PCs and embedded platforms are diverging. On a PC +usually a budget card provides the full raw transport stream and decoding +and processing is main CPU's task. On embedded platforms, however, data is +multiplexed by specialized hardware or firmware for direct application use +which relieves the main CPU from these tasks. Therefore, Linux DVB +API Version 4 was suggested, but unfortunally never completed. + + +Today, the LinuxTV project is an independend and non-profit community project +by DVB/V4L enthusiasts and developers interested in Digital TV and Analog TV, +sharing the same hg tree. + +However, this document describes only the digital TV part. + + +With the further development of newer DTV standards, the existing version +3 of the Linux DVB API was no longer able to support all DTV standards and +newer hardware. Two concurrent approaches to overcome the problem where +proposed, \texttt{Multiproto} and \texttt{S2API}. + +At +\href {http://www.linuxtv.org/news.php?entry=2008-09-19.mchehab}{Linux Plumbers Conference 2008} +the decision was made towards to S2API, basically an extension to +\texttt{DVB API Version 3} called \texttt{DVB API Version 5}. + + +This Linux DVB API documentation will be extended to reflect these additions. \newpage \section{Overview} @@ -49,7 +86,7 @@ provides a first implementation of the L \end{figure} -A DVB PCI card or DVB set-top-box (STB) usually consists of the following +A DVB device or DVB set-top-box (STB) usually consists of the following main hardware components: \begin{itemize} \item Frontend consisting of tuner and DVB demodulator @@ -85,10 +122,10 @@ a TV set. Figure \ref{fig:dvbstb} shows a crude schematic of the control and data flow between those components. -On a DVB PCI card not all of these have to be present since some -functionality can be provided by the main CPU of the PC (e.g. MPEG picture -and sound decoding) or is not needed (e.g. for data-only uses like -``internet over satellite''). +On a DVB card not all of these have to be present since some +functionality can be provided by the main CPU of the PC (e.g. MPEG video +and audio decoding) or is not needed (e.g. for data-only uses like +``internet over satellite''). In fact, almost all new DTV devices use the CPU for MPEG decoding. Also not every card or STB provides conditional access hardware. \section{Linux DVB Devices} @@ -117,12 +154,11 @@ All devices can be found in the \texttt{ \item \texttt{/dev/dvb/adapterN/demuxM}, \item \texttt{/dev/dvb/adapterN/caM}, \end{itemize} -where N enumerates the DVB PCI cards in a system starting from~0, +where N enumerates the DVB adapters (pci cards, usb devices, ..) in a system starting from~0, and M enumerates the devices of each type within each adapter, starting from~0, too. We will omit the ``\texttt{/dev/dvb/adapterN/}'' in the further dicussion of -these devices. The naming scheme for the devices is the same wheter devfs -is used or not. +these devices. More details about the data structures and function calls of all the devices are described in the following chapters. @@ -137,10 +173,13 @@ in application sources with a partial pa #include \end{verbatim} -To enable applications to support different API version, an additional +To enable applications to support different API versions, an additional include file \texttt{linux/dvb/version.h} exists, which defines the constant \texttt{DVB\_API\_VERSION}. This document describes -\texttt{DVB\_API\_VERSION~3}. +\texttt{DVB\_API\_VERSION~5}. + +Since API version 5 an API command for quering API version also exists, +allowing user space applications to detect API version during runtime. %%% Local Variables: %%% mode: latex diff -Nrup v4l-dvb-359d95e1d541/dvb-spec/dvbapi/title.tex v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/title.tex --- v4l-dvb-359d95e1d541/dvb-spec/dvbapi/title.tex 2009-02-18 13:49:37.000000000 +0100 +++ v4l-dvb-a7ea3df69673/dvb-spec/dvbapi/title.tex 2009-02-22 09:33:54.766093761 +0100 @@ -1,16 +1,20 @@ \pagenumbering{arabic} \pagestyle{empty} -\title{\huge\textbf{LINUX DVB API Version 3}} +\title{\huge\textbf{LINUX DVB API Version 5}} \author{ \includegraphics{cimlogo.psi}\\ - Copyright 2002, 2003 Convergence GmbH\\\\ + Copyright:\\ + 2002, 2003 Convergence GmbH,\\ + 2008, 2009 www.linuxtv.org\\\\ Written by Dr. Ralph J.K. Metzler\\ - \texttt{}\\\\ + \texttt{}\\ and Dr. Marcus O.C. Metzler\\ - \texttt{}\\ + \texttt{},\\ + and The Linux DVB developers\\ + \texttt{http://www.linuxtv.org}\\\\ } -\date{24/07/2003\\V 1.0.0} +\date{22/02/2009\\Version 1.1.0} \maketitle