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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32460C4332F for ; Thu, 11 Nov 2021 15:06:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19A6961252 for ; Thu, 11 Nov 2021 15:06:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233799AbhKKPJn (ORCPT ); Thu, 11 Nov 2021 10:09:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233798AbhKKPJj (ORCPT ); Thu, 11 Nov 2021 10:09:39 -0500 Received: from mail-lj1-x22e.google.com (mail-lj1-x22e.google.com [IPv6:2a00:1450:4864:20::22e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5194EC061767; Thu, 11 Nov 2021 07:06:50 -0800 (PST) Received: by mail-lj1-x22e.google.com with SMTP id 1so12548066ljv.2; Thu, 11 Nov 2021 07:06:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=atEvBZS6JbH/fBakpxl0ydNMlsxU8a3CAtxPkHgUBao=; b=LbEOQHk3kfHEAj//dva6jU1GJiv3HQ0rVQnV+XhhrL2EQeC2olmucVRAU9Cj7ghLva yOx3bDdeVY4nZ4+l37woZHhXAmw8QmhhGSNO77e4WNFz+kM38flm75wNmQ8zS6YgV6Vp q/HSCKUlDf8JNPyHo2Or8qCncVvI/1kM5VMI69bnSu6aodrjQZZypdRqTBcFwBPJATaa kc3ogUpC6cPbMb50hOATzFHke/z9Cs4xRF6TDvon25eE9cgmnABeErPskpSX87lEuYsI 5C2rH26s+SoDXiPpxXMuNGPQ8JI52eEq81gsDAer0MpRr3E5Db1+rVC07agGEf/SSEbN qajg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=atEvBZS6JbH/fBakpxl0ydNMlsxU8a3CAtxPkHgUBao=; b=AQCWzvNlC8YIWanwW08iEHs244c7KC3DKnz2JaUYxWo10Y0zej7PT10gO3St/FAWX6 /SVxsRez76BWkShSIe5E7Vu/z3SQWuvLrLftAqgDgygtVm9h57kMPAUTFw4O5ciEfXkZ x9AMcsVCNUi6un+IjpIAM8xF+gCuvNZcNHi2o/iqxnNIvqxyrnkMHbbGdJbobmyky9Wa fl3Ft0tIo7g4h0rI2Jc/CMiSQTm8uakxtcnYqXQlNU0itGI5q7PlR7rBnKzkmsj4sUH6 ny4aBlbwxxRAWhxEagae9oBay+Qcs6yRlplffO2qhx00O94eT/lNKBl8rzh4XVD94e7y 8gZA== X-Gm-Message-State: AOAM532s1XgxCI+zcYK4FtHxNL3rHc624cDRRSkcYVa7fyce20bZsCCt yQTARhhmZUXKmTk5WyGJOfs= X-Google-Smtp-Source: ABdhPJzTWLuwNN9l+pwtH1zTo7roHWjcBfwY6YyodN5aV17cRAD0iKv9VEGBAwG05nQOrFA/uILl5w== X-Received: by 2002:a2e:bd09:: with SMTP id n9mr7788404ljq.40.1636643208712; Thu, 11 Nov 2021 07:06:48 -0800 (PST) Received: from mobilestation ([95.79.188.236]) by smtp.gmail.com with ESMTPSA id u3sm306633lft.215.2021.11.11.07.06.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Nov 2021 07:06:48 -0800 (PST) Date: Thu, 11 Nov 2021 18:06:45 +0300 From: Serge Semin To: Mark Brown , nandhini.srikandan@intel.com Cc: Serge Semin , robh+dt@kernel.org, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, mgross@linux.intel.com, kris.pan@intel.com, kenchappa.demakkanavar@intel.com, furong.zhou@intel.com, mallikarjunappa.sangannavar@intel.com, mahesh.r.vaidya@intel.com, rashmi.a@intel.com Subject: Re: [PATCH v3 1/5] dt-bindings: spi: Add SSTE support for DWC SSI controller Message-ID: <20211111150645.f6qmnzy6hcoiatun@mobilestation> References: <20211111065201.10249-1-nandhini.srikandan@intel.com> <20211111065201.10249-2-nandhini.srikandan@intel.com> <20211111143108.pxovseqvm2ywmoc2@mobilestation> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 11, 2021 at 03:01:12PM +0000, Mark Brown wrote: > On Thu, Nov 11, 2021 at 05:31:08PM +0300, Serge Semin wrote: > > > BTW Mark, why not to have a generic DT-property which would set that > > flag automatically by the SPI-core subsystem seeing it's indeed a > > client device-property? For instance there can be some property like > > "spi-cs-toggle" DT-property which when specified for the particular > > SPI-client DT-node will make the SPI-core subsystem to set the > > Anything like this is fundamentally part of the wire protocol for the > device, there's no need for an extra property on top of the compatible > for the device and the driver really, really needs to know what's going > on to avoid data corruption. You could also use this feature together > with varying the word size as an optimisation at runtime (eg, do long > sequences of register writes in a single hardware operation by setting > an appropriate word length to cause the controller to bounce chip > select between writes). > > > SPI_CS_WORD flag of the device mode? Like it has already been done for > > "spi-cs-high"/"spi-lsb-first"/etc. > > I don't think either of those properties was a good idea, there's a > bunch of stuff in the older SPI bindings that don't make much sense. Ok. Thanks for clarification. No new DT-property then. Nandhini, could you please drop this patch in v4? One more time I'm sorry for misleading you on v2. -Sergey