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=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 E622AC43331 for ; Mon, 30 Mar 2020 16:32:58 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4F94A20578 for ; Mon, 30 Mar 2020 16:32:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="cXNY7RJU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4F94A20578 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 9EE0615F9; Mon, 30 Mar 2020 18:32:06 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 9EE0615F9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1585585976; bh=7YLPfHYzvcjsitPmeEChTl9Q/c63c9iJrj1hH472ybo=; h=Date:From:To:Subject:References:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=cXNY7RJUzezS37eqad4hEEzILe4n2VDSOwAnbRw+QX//rz3ACSeikRfcKZRP7lEEU jQpjfvAol37gwSh6D187Am1eZ2S4YNtoehQit/OIqrXYW2q8//rnltMo+sCNmFgJpR kQbKfE7CRTMsoMONbmWd2yCnuY2LCaQxMQQ94OjQ= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id D7E48F80145; Mon, 30 Mar 2020 18:32:05 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 30B43F80148; Mon, 30 Mar 2020 18:32:00 +0200 (CEST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by alsa1.perex.cz (Postfix) with ESMTP id 4705DF800EB for ; Mon, 30 Mar 2020 18:31:46 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 4705DF800EB Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 64CED1042; Mon, 30 Mar 2020 09:31:44 -0700 (PDT) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D9D5B3F71E; Mon, 30 Mar 2020 09:31:43 -0700 (PDT) Date: Mon, 30 Mar 2020 17:31:42 +0100 From: Mark Brown To: Matt Flax Subject: Re: [PATCH] ASoC: snd_soc_dai_set_fmt add substream independence. Message-ID: <20200330163142.GI4792@sirena.org.uk> References: <20200328015831.6230-1-flatmax@flatmax.org> <20200330103213.GA4792@sirena.org.uk> <3c00bf93-04a8-04af-e0b5-d0f76f5dbb06@flatmax.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="Op27XXJsWz80g3oF" Content-Disposition: inline In-Reply-To: <3c00bf93-04a8-04af-e0b5-d0f76f5dbb06@flatmax.org> X-Cookie: Ahead warp factor one, Mr. Sulu. User-Agent: Mutt/1.10.1 (2018-07-13) Cc: alsa-devel@alsa-project.org, lars@metafoo.de, lgirdwood@gmail.com, pierre-louis.bossart@linux.intel.com X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" --Op27XXJsWz80g3oF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Mar 30, 2020 at 11:28:26PM +1100, Matt Flax wrote: > On 30/3/20 9:32 pm, Mark Brown wrote: > > On Sat, Mar 28, 2020 at 12:58:31PM +1100, Matt Flax wrote: > > > This patch is aims to start a stronger discussion on allowing both CPU > > > and Codec dais to set formats independently based on direction. > > If the DAIs support completely separate formats they're not a single DAI > > and should be represented as two DAIs. > I understand, however having two DAIs produces subdevices and pushes the > overhead of managing registers to the end user in the form of two sub > devices. I think that's a swings and roundabouts thing where it really depends on your use case - for example if the DAIs can be organized however people like then people can come up with creative ways to wire things that don't pair things in the way that makes sense for userspace. Ideally we'd be able to match up any playback only stream with any capture only stream which would help a much wider range of systems. > Is everyone firm on the concept that a DAI's playback and capture stream has > to have the same format in the same DAI ? > I can see a much better solution (then the one I posted here) which is also > very simple to solve this problem in the same DAI. It does push a requirement for dealing with asymmetric setups including validation that nobody did anything that can't be supported onto all users to at least some extent, even if standard stuff were factored out into the core (which didn't happen yet). This is for a *very* unusual requiremenet. > > having an asymmetric configuration. You probably need to represent > > these isolators as a CODEC and do a CODEC to CODEC link and even then it > > seems worrying. > I like to think of isolation as innovative, not worrying :) > However w.r.t. the codec to codec link approach, I will take your advice and > not go down that route. No, my advice is to go down that route if you are doing this. I'm just not convinced that it's going to work reliably since this all sounds rather shaky. --Op27XXJsWz80g3oF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl6CHu0ACgkQJNaLcl1U h9B25Qf/T5vJZAS/Fv5gDforAG223ex9jg1vhJu/1mHrKrtt9x7R0+tWYV1Jic/I dc+eI4LLoLeHiEGXEGuWxgcPpygK8+Elos5pEtcCxA6IzG7YODMdL/HPTmqHDrOd A3a2j1kHS/Ga7uxUf/SkCumBfIx3f3yOMt/JQ8MVkcwjg4g1Dg6XXEfm31MAnWbW FGzrmHOj/U3s4SWE6I0mKVvjqYpQusXE5LHyB6mhdc4yuPzJdva4xXL8yLL/0tVH ++vWjBottWcSoVbldGKymgLMj+rG4nkVVuOk4wix0h5DEdgV7EZXfIMkYh84036e I2UX2bmsxFWasW9qHQhgFsxh+hNbvg== =Gbt9 -----END PGP SIGNATURE----- --Op27XXJsWz80g3oF--