From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933269AbbDITg7 (ORCPT ); Thu, 9 Apr 2015 15:36:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56580 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755939AbbDITg4 (ORCPT ); Thu, 9 Apr 2015 15:36:56 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH] dvb: Document FE_SCALE_DECIBEL units consistently From: David Howells To: mchehab@osg.samsung.com Cc: dhowells@redhat.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Date: Thu, 09 Apr 2015 20:36:49 +0100 Message-ID: <20150409193649.6875.19630.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In comments and in the documentation, the units of properties marked with the FE_SCALE_DECIBEL scale are specified in terms of 1/1000 dB or 0.0001 dB. This is inconsistent, however, as 1/1000 is 0.001, not 0.0001. Note that the v4l-utils divide the value by 1000 for the signal strength suggesting that the 1/1000 is correct. Settle on millidecibels, ie. 1/1000dB or 0.001dB. Signed-off-by: David Howells --- Documentation/DocBook/media/dvb/dvbproperty.xml | 4 ++-- include/uapi/linux/dvb/frontend.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/Documentation/DocBook/media/dvb/dvbproperty.xml b/Documentation/DocBook/media/dvb/dvbproperty.xml index 3018564..7ddab2b 100644 --- a/Documentation/DocBook/media/dvb/dvbproperty.xml +++ b/Documentation/DocBook/media/dvb/dvbproperty.xml @@ -953,7 +953,7 @@ enum fe_interleaving { Possible scales for this metric are: FE_SCALE_NOT_AVAILABLE - it failed to measure it, or the measurement was not complete yet. - FE_SCALE_DECIBEL - signal strength is in 0.0001 dBm units, power measured in miliwatts. This value is generally negative. + FE_SCALE_DECIBEL - signal strength is in 0.001 dBm units, power measured in miliwatts. This value is generally negative. FE_SCALE_RELATIVE - The frontend provides a 0% to 100% measurement for power (actually, 0 to 65535). @@ -963,7 +963,7 @@ enum fe_interleaving { Possible scales for this metric are: FE_SCALE_NOT_AVAILABLE - it failed to measure it, or the measurement was not complete yet. - FE_SCALE_DECIBEL - Signal/Noise ratio is in 0.0001 dB units. + FE_SCALE_DECIBEL - Signal/Noise ratio is in 0.001 dB units. FE_SCALE_RELATIVE - The frontend provides a 0% to 100% measurement for Signal/Noise (actually, 0 to 65535). diff --git a/include/uapi/linux/dvb/frontend.h b/include/uapi/linux/dvb/frontend.h index c56d77c..466f569 100644 --- a/include/uapi/linux/dvb/frontend.h +++ b/include/uapi/linux/dvb/frontend.h @@ -467,7 +467,7 @@ struct dtv_cmds_h { * @FE_SCALE_NOT_AVAILABLE: That QoS measure is not available. That * could indicate a temporary or a permanent * condition. - * @FE_SCALE_DECIBEL: The scale is measured in 0.0001 dB steps, typically + * @FE_SCALE_DECIBEL: The scale is measured in 0.001 dB steps, typically * used on signal measures. * @FE_SCALE_RELATIVE: The scale is a relative percentual measure, * ranging from 0 (0%) to 0xffff (100%). @@ -516,7 +516,7 @@ struct dtv_stats { __u8 scale; /* enum fecap_scale_params type */ union { __u64 uvalue; /* for counters and relative scales */ - __s64 svalue; /* for 0.0001 dB measures */ + __s64 svalue; /* for 0.001 dB measures */ }; } __attribute__ ((packed));