From patchwork Wed Jun 8 01:45:37 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 860472 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.4) with ESMTP id p581g6RW015583 for ; Wed, 8 Jun 2011 02:08:37 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754358Ab1FHBqH (ORCPT ); Tue, 7 Jun 2011 21:46:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:10726 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754335Ab1FHBqF (ORCPT ); Tue, 7 Jun 2011 21:46:05 -0400 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p581k5s9001184 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 7 Jun 2011 21:46:05 -0400 Received: from pedra (vpn-236-210.phx2.redhat.com [10.3.236.210]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p581jncB007506 for ; Tue, 7 Jun 2011 21:46:04 -0400 Date: Tue, 7 Jun 2011 22:45:37 -0300 From: Mauro Carvalho Chehab Cc: Linux Media Mailing List Subject: [PATCH 10/15] [media] DocBook/frontend.xml: Recomend the usage of the new API Message-ID: <20110607224537.1d34d54a@pedra> In-Reply-To: References: Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.67 on 10.5.11.12 To: unlisted-recipients:; (no To-header on input) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Wed, 08 Jun 2011 02:08:38 +0000 (UTC) The old way of setting delivery system parameters were to use an union with specific per-system parameters. However, as newer delivery systems required more data, the structure size weren't enough to fit. So, recomend using the DVBS2API instead. Signed-off-by: Mauro Carvalho Chehab diff --git a/Documentation/DocBook/media/dvb/frontend.xml b/Documentation/DocBook/media/dvb/frontend.xml index b1f0123..086e62b 100644 --- a/Documentation/DocBook/media/dvb/frontend.xml +++ b/Documentation/DocBook/media/dvb/frontend.xml @@ -221,8 +221,20 @@ by
frontend parameters The kind of parameters passed to the frontend device for tuning depend on -the kind of hardware you are using. All kinds of parameters are combined as an -union in the FrontendParameters structure: +the kind of hardware you are using. +The struct dvb_frontend_parameters uses an +union with specific per-system parameters. However, as newer delivery systems +required more data, the structure size weren't enough to fit, and just +extending its size would break the existing applications. So, those parameters +were replaced by the usage of +FE_GET_PROPERTY/FE_SET_PROPERTY ioctl's. The +new API is flexible enough to add new parameters to existing delivery systems, +and to add newer delivery systems. +So, newer applications should use +FE_GET_PROPERTY/FE_SET_PROPERTY instead, in +order to be able to support the newer System Delivery like DVB-S2, DVB-T2, +DVB-C2, ISDB, etc. +All kinds of parameters are combined as an union in the FrontendParameters structure: struct dvb_frontend_parameters { uint32_t frequency; /⋆ (absolute) frequency in Hz for QAM/OFDM ⋆/