From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.kapsi.fi ([217.30.184.167]:40174 "EHLO mail.kapsi.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751534AbbE1F0h (ORCPT ); Thu, 28 May 2015 01:26:37 -0400 Message-ID: <5566A70A.1090805@iki.fi> Date: Thu, 28 May 2015 08:26:34 +0300 From: Antti Palosaari MIME-Version: 1.0 To: Hurda , linux-media@vger.kernel.org Subject: Re: si2168/dvbsky - blind-scan for DVB-T2 with PLP fails References: <556644C7.8040701@chello.at> In-Reply-To: <556644C7.8040701@chello.at> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 05/28/2015 01:27 AM, Hurda wrote: > Hello. > > I think I came across a bug in either of the drivers si2168 and dvbsky > regarding > blind-scanning DVB-T2-frequencies. > > HW: Technotrend CT2-4400v2 (afaik based on or the same as DVBSky T330) > demod: Si2168-B40 > tuner: Si2158-A20 > OS: Ubuntu 15.04 (kernel 3.19) > > In Austria, the DVB-T2-service "SimpliTV" is currently airing up to four > muxes, next to one or two DVB-T-muxes. > In my region, the frequencies are 490MHz, 546MHz, 690MHz, 714MHz for > DVB-T2, > and 498MHz for DVB-T. > These numbers might be of interest when reading the logs. > > The peculiar aspect of these T2-muxes is that they're aired on PLP 1 > without > there being a PLP 0. I think this is also the root of my problem. dvbv5-scan is working, but w_scan not? Could you hack si2168.c file and test? if (c->delivery_system == SYS_DVBT2) { /* select PLP */ cmd.args[0] = 0x52; cmd.args[1] = c->stream_id & 0xff; // cmd.args[2] = c->stream_id == NO_STREAM_ID_FILTER ? 0 : 1; cmd.args[2] = 0; cmd.wlen = 3; cmd.rlen = 1; ret = si2168_cmd_execute(client, &cmd); if (ret) goto err; } Antti > > > When doing a blind-scan using w_scan 20140727 on Ubuntu 15.04 (kernel > 3.19), > w_scan does not find any of these four DVB-T2-muxes. > It just finds the DVB-T-mux. > > Logs: > media-tree_dmesg_lsusb.txt http://pastebin.com/0ixFPMSA > media-tree_w_scan.txt http://pastebin.com/yyG3jSwj > > The found transponder: > initial_v3_media_build_trunk.conf http://pastebin.com/LmFQavpy > initial_v5.conf http://pastebin.com/Jx6kymVt > > I also tried a fresh checkout from git.linuxtv.org as of last weekend > and the > most recent w_scan version (20141122). > > As you can see, w_scan tries to tune(?) the DVB-T2-frequencies, but > ultimately doesn't find anything on them. > > > Then I tried the DVBSky-linux-driver[1] > (media_build-bst-20150322.tar.gz)[2] > from their site, which is using a binary called sit2 for this card. > Using this driver, w_scan found all four DVB-T2-muxes and the DVB-T-mux. > Additionally, it found the DVB-T2-muxes during the DVB-T-scan. > > Logs: > media_build-bst_dmesg_lsusb.txt http://pastebin.com/vJeDMxtu > media_build-bst_w_scan.txt http://pastebin.com/yhwAYjen > > Found transponders: > initial_v3_bst.conf http://pastebin.com/ECKQvRWX > initial_v5_bst.conf http://pastebin.com/CbhY6Hpz > > Of course, doing a channel-scan using dvbv5-scan on these transponders > worked > too: > > dvbv5_sit2.conf http://pastebin.com/3W52bbhv > dvbv5_sit2.log http://pastebin.com/nc66PTkt > > Afterwards, I tried to do a channel-scan with the same initial tuning-file > using the opensource-driver, which also worked: > > dvbv5_si2168.conf http://pastebin.com/A6FbqUL1 > dvbv5_si2168.log http://pastebin.com/ewyVPJR2 > > This should verify that tuning PLP 1 without there being PLP 0 is not > the issue. > > > Additionally, if you compare the two channel-lists, you find interesting > differences: > > The scan with si2168 has AUTO for "MODULATION" and "INVERSION" for > DVB-T2-channels, and for "CODE_RATE_LP" and "INVERSION" for DVB-T-channels. > > The scan with sit2 has the respective values in the channel-list. > > The dvbv5-scan-logs also differ, as using sit2 also displays the signal > quality > during tuning. > > > I know that there were changes regarding DVB-T2-scanning[3], but as the > blog- > article specifically mentions si2168 and w_scan to be fully dvbv5-compliant > and good for using with DVB-T2, I thought you should know about this > particular problem. > > > In the attachment I've packed the previously linked logs, for archival > reasons. > > > Thank you for your attention. > > [1] http://www.dvbsky.net/Support_linux.html > [2] http://www.dvbsky.net/download/linux/media_build-bst-150322.tar.gz > [3] http://blog.palosaari.fi/2014/09/linux-dvb-t2-tuning-problems.html > > PS: Interesting comments regarding auto-detection for si2168: > http://blog.palosaari.fi/2014/09/linux-dvb-t2-tuning-problems.html?showComment=1427233615765#c8591459871945922951 > > http://blog.palosaari.fi/2014/09/linux-dvb-t2-tuning-problems.html?showComment=1427234034259#c6500661729983566638 > -- http://palosaari.fi/