From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC90AC4646C for ; Mon, 24 Jun 2019 23:09:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8722920674 for ; Mon, 24 Jun 2019 23:09:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=kapsi.fi header.i=@kapsi.fi header.b="HgD8sJKu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728047AbfFXXJe (ORCPT ); Mon, 24 Jun 2019 19:09:34 -0400 Received: from mail.kapsi.fi ([91.232.154.25]:58179 "EHLO mail.kapsi.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728045AbfFXXJd (ORCPT ); Mon, 24 Jun 2019 19:09:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kapsi.fi; s=20161220; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=ybCFAimgKnGfD644+HUiORlUw4LHMAcslZVJ5ERYh6w=; b=HgD8sJKur7Bf6JCWF2A1MLOIEB +7FiX5fRFNfXbV3bVNfAwbAc7Wyof+smcyWAG2cmaZtYlis/SV+nPoIJIZ9pLF09qGDAWh6BrCBKd 8bm8eOz5EDsXBtYO3/XTA+PMRc3kLj0zecHsKg3FqoB3LNzRdMeax9M1Fdg/KV/yM4nCB4Bfo5Lob W+un7tV42fIDaIi5RhN59zfTy/4e691XXV6IptYWkSZodbqYZHRhDeUpbeANMau8LHFaugoLHGFIP b6+KO+Votb4+conFYSxQrb6vGU23IbJgcy/efEQDa1inMR6bhiyC9TNicalXwwOlzMa0YA/PzHcsx 4/g+sCbg==; Received: from mobile-access-bceedd-68.dhcp.inet.fi ([188.238.221.68] helo=localhost.localdomain) by mail.kapsi.fi with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1hfY5c-00080v-0D; Tue, 25 Jun 2019 02:09:32 +0300 Subject: Re: si2168 gapped clock To: Marc Gonzalez , Olli Salonen Cc: linux-media , Mauro Carvalho Chehab References: From: Antti Palosaari Message-ID: <8b54e64c-8a56-c917-a712-1e708f48f4b6@iki.fi> Date: Tue, 25 Jun 2019 02:09:28 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 188.238.221.68 X-SA-Exim-Mail-From: crope@iki.fi X-SA-Exim-Scanned: No (on mail.kapsi.fi); SAEximRunCond expanded to false Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hello, On 6/18/19 7:47 PM, Marc Gonzalez wrote: > Hello, > > In the qcom SoC, the TS interface has two modes of operation. > > - with 3 signals (clk, valid, data) > - with 4 signals (clk, valid, data, sync) > > In the si2168 short datasheet, I can see a diagram with these > 4 signals. > > My question is: how do we configure the si2168 demod to be > in the first mode or the second mode? > > Is it the ts_clock_gapped parameter? > > ts_clock_gapped=0 means no sync > ts_clock_gapped=1 means with sync ??? > > Regards. > In general for mpeg ts you will need: data + clock + valid : when clock is running continuously or data + clock : when clock is running only when there is data Valid is used to tell there is new data when clock is running continuously - when valid signal is not set there is no data even clock is running. When only data and clock lines are used, clock is ran only when there is data. Sync signal is set for beginning of every TS packet (and it is not hardly needed if you parse ts data by software for example). Thus ts_clock_gapped means demod will flip clock only when there is data to feed ==> no need for valid signal. Configuring demod to first *or* second mode should be just ts_clock_gapped=false. regards Antti -- http://palosaari.fi/