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=-3.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 5B784C282C0 for ; Fri, 25 Jan 2019 17:47:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28ABA218A2 for ; Fri, 25 Jan 2019 17:47:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548438442; bh=0Z+qTGaRKSxDsSh+kYy2Jmy+M1JfTLTxZMhiniM5sb8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=xbqKXbi6vUUWJ2UZd1Zc6JdLlokJAmB5T6fvVehXZ5YV8dma0IGnUutnE1bfFubdb 63qM0JrrmoaCKaTRtHAepO25Ep9B/fHr7tG+URn50Es0l3qInZ2mfoGs7fcUeEgFo8 v+omw8yy9Z3amB0wy2VQjXVpB9UAt5FaSqw7gjbQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729346AbfAYRrU (ORCPT ); Fri, 25 Jan 2019 12:47:20 -0500 Received: from heliosphere.sirena.org.uk ([172.104.155.198]:34296 "EHLO heliosphere.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726252AbfAYRrT (ORCPT ); Fri, 25 Jan 2019 12:47:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sirena.org.uk; s=20170815-heliosphere; h=In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding: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=jp0ESmevg+3eVpFgCSGhcwzL//NUG3B5AKD7zupC8Hc=; b=Ses3Y4S43xeXfAlYZJCNTZR7p uruvwJolTHIr7d2VfhcJzfuUqbbJL7bNf80MkV3r6PT14TZZteQnvqUY2ihYyqQ/pa0KwxWsxSqJu IH9XsDa8Brg//RTwnw5PEQq63PScTSzEQJcMKUfU0UssHnZCsnivfeMt3SrnmTitmLJT0=; Received: from cpc102320-sgyl38-2-0-cust46.18-2.cable.virginm.net ([82.37.168.47] helo=debutante.sirena.org.uk) by heliosphere.sirena.org.uk with esmtpa (Exim 4.89) (envelope-from ) id 1gn5ZS-0004Qp-KL; Fri, 25 Jan 2019 17:47:14 +0000 Received: by debutante.sirena.org.uk (Postfix, from userid 1000) id E766E1126FC0; Fri, 25 Jan 2019 17:47:13 +0000 (GMT) Date: Fri, 25 Jan 2019 17:47:13 +0000 From: Mark Brown To: Jonas Bonn Cc: Baolin Wang , LKML , linux-spi , Rob Herring , Mark Rutland , DTML Subject: Re: [PATCH 1/2] spi: support inter-word delay requirement for devices Message-ID: <20190125174713.GA6939@sirena.org.uk> References: <20190125114429.20066-1-jonas@norrbonn.se> <20190125114429.20066-2-jonas@norrbonn.se> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="M9NhX3UHpAaciwkO" Content-Disposition: inline In-Reply-To: X-Cookie: diplomacy, n: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --M9NhX3UHpAaciwkO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, Jan 25, 2019 at 01:06:45PM +0100, Jonas Bonn wrote: > On 25/01/2019 12:53, Baolin Wang wrote: > > On Fri, 25 Jan 2019 at 19:44, Jonas Bonn wrote: > > Can we configure it at runtime by the device rather than at DT time by > > the controller? If yes, we already have a patch for this, please > > check: > It's a characteristic of the SPI slave, in the same sense as CPOL/CPHA are, > and therefore it makes sense to specify it in the device tree. No, that doesn't follow at all. There's two bits here - where the configuration gets done and the mechanism by which it gets done. If something in DT is completely orthogonal to which device it is a property of. > Having this as device property rather than a transfer property allows this > to be configured one time in setup() rather than having to fiddle with the > configuration register for every transfer. That doesn't mean that the coniguration should be done in DT though, and given that this presumably is a property of the device there seems to be no reason why we'd have it in DT - if every instance of the device is going to need to set the property we should just figure it out from the compatble string instead. --M9NhX3UHpAaciwkO Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlxLS58ACgkQJNaLcl1U h9Ci1Af+KPQ6Fd4EwOmXjTuA/3wvO5WHx034mRClNaY5DwGvpFwEr3ZJmUQlIDND 5Sd8+g6AjlOmkjsv7Lhoe2UCvYcPVUqbr5J0HId083UZDlHi7vIBChD9JnW5a0Up u0aur6HuzudvMplSCT1eaCtp0EZ81TdwfPsLESCTAe1dGUQUSANCpv2SpbJfDtBO dLituQEv3GeGhiGtoEcfajriq0k+IaI/zC6D+iaFgR1qgzU9YCmPQCYtw+MtaI2X nUXxQyOx8G7W09bToK55cHSBd6k5uwrCBK0rGbDERSp+h+nnQoZMiLxxFMVd+PTm ceJVw/ruBPHRTpIz0bLX3wrAUWLiXQ== =xcYV -----END PGP SIGNATURE----- --M9NhX3UHpAaciwkO--