Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752090AbdHaXrU (ORCPT ); Thu, 31 Aug 2017 19:47:20 -0400 Received: from ec2-52-27-115-49.us-west-2.compute.amazonaws.com ([52.27.115.49]:44930 "EHLO osg.samsung.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751815AbdHaXrJ (ORCPT ); Thu, 31 Aug 2017 19:47:09 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Mauro Carvalho Chehab To: Linux Doc Mailing List , Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, Jonathan Corbet Subject: [PATCH 09/15] media: fe_property_parameters.rst: better document bandwidth Date: Thu, 31 Aug 2017 20:46:56 -0300 Message-Id: <3ed72e42a2eba581a84074b3b26c9190563c6310.1504222628.git.mchehab@s-opensource.com> X-Mailer: git-send-email 2.13.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2805 Lines: 71 Use a table to document the supported bandwidths. That makes it clearer to readers. Signed-off-by: Mauro Carvalho Chehab --- .../media/uapi/dvb/fe_property_parameters.rst | 44 +++++++++++++--------- 1 file changed, 26 insertions(+), 18 deletions(-) diff --git a/Documentation/media/uapi/dvb/fe_property_parameters.rst b/Documentation/media/uapi/dvb/fe_property_parameters.rst index e085e84fef38..49470f7dda02 100644 --- a/Documentation/media/uapi/dvb/fe_property_parameters.rst +++ b/Documentation/media/uapi/dvb/fe_property_parameters.rst @@ -116,30 +116,38 @@ Should be set only for terrestrial delivery systems. Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``, ``8000000``, ``10000000``. +======================= ======================================================= +Terrestrial Standard Possible values for bandwidth +======================= ======================================================= +ATSC (version 1) No need to set. It is always 6MHz. +DMTB No need to set. It is always 8MHz. +DVB-T 6MHz, 7MHz and 8MHz. +DVB-T2 1.172 MHz, 5MHz, 6MHz, 7MHz, 8MHz and 10MHz +ISDB-T 5MHz, 6MHz, 7MHz and 8MHz, although most places + use 6MHz. +======================= ======================================================= + + .. note:: - #. DVB-T supports 6, 7 and 8MHz. - #. DVB-T2 supports 1.172, 5, 6, 7, 8 and 10MHz. + #. For ISDB-Tsb, the bandwidth can vary depending on the number of + connected segments. - #. ISDB-T supports 5MHz, 6MHz, 7MHz and 8MHz, although most - places use 6MHz. - - #. On DVB-C and DVB-S/S2, the bandwidth depends on the symbol rate. - So, the Kernel will silently ignore setting :ref:`DTV-BANDWIDTH-HZ`. - - #. For DVB-C and DVB-S/S2, the Kernel will return an estimation of the - bandwidth, calculated from :ref:`DTV-SYMBOL-RATE` and from - the rolloff, with is fixed for DVB-C and DVB-S. - - #. For DVB-S2, the bandwidth estimation will use :ref:`DTV-ROLLOFF`. - - #. For ISDB-Tsb, it can vary depending on the number of connected - segments. - - #. Bandwidth in ISDB-Tsb can be easily derived from other parameters + It can be easily derived from other parameters (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT). + #. On Satellite and Cable delivery systems, the bandwidth depends on + the symbol rate. So, the Kernel will silently ignore any setting + :ref:`DTV-BANDWIDTH-HZ`. I will however fill it back with a + bandwidth estimation. + + Such bandwidth estimation takes into account the symbol rate set with + :ref:`DTV-SYMBOL-RATE`, and the rolloff factor, with is fixed for + DVB-C and DVB-S. + + For DVB-S2, the rolloff should also be set via :ref:`DTV-ROLLOFF`. + .. _DTV-INVERSION: -- 2.13.5