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 34CC1C433F5 for ; Thu, 30 Sep 2021 12:36:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1BE00613A6 for ; Thu, 30 Sep 2021 12:36:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350927AbhI3Mhu (ORCPT ); Thu, 30 Sep 2021 08:37:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350920AbhI3Mht (ORCPT ); Thu, 30 Sep 2021 08:37:49 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70BB2C06176D; Thu, 30 Sep 2021 05:36:06 -0700 (PDT) Received: from [IPv6:2a02:810a:880:f54:fd5c:7cb1:aaa8:78b1] (unknown [IPv6:2a02:810a:880:f54:fd5c:7cb1:aaa8:78b1]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: dafna) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 423711F44C22; Thu, 30 Sep 2021 13:36:04 +0100 (BST) Subject: Re: [PATCH] Revert "spi: modify set_cs_timing parameter" To: Mark Brown Cc: kernel@collabora.com, linux-spi@vger.kernel.org, enric.balletbo@collabora.com, dafna3@gmail.com, Mason Zhang , Laxman Dewangan , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com, Matthias Brugger References: <20210930120700.2564-1-dafna.hirschfeld@collabora.com> <20210930122513.GX4199@sirena.org.uk> From: Dafna Hirschfeld Message-ID: <28f8af42-4535-ef9f-e521-712d37e2cb72@collabora.com> Date: Thu, 30 Sep 2021 14:36:01 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210930122513.GX4199@sirena.org.uk> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi, thanks for the fast feedback On 30.09.21 14:25, Mark Brown wrote: > On Thu, Sep 30, 2021 at 02:07:00PM +0200, Dafna Hirschfeld wrote: >> This reverts commit 04e6bb0d6bb127bac929fb35edd2dd01613c9520. > > Please submit patches using subject lines reflecting the style for the > subsystem, this makes it easier for people to identify relevant patches. > Look at what existing commits in the area you're changing are doing and > make sure your subject lines visually resemble what they're doing. > There's no need to resubmit to fix this alone. > >> This revert the commit 'spi: modify set_cs_timing parameter' >> and its following commit >> 'spi: mediatek: fix build warnning in set cs timing'. > > Which is not what the commit message nor the paste of the full hash > claimed :/ What is the paste of the full hash? Since the second commit is only a warning fixes I thought it is cumbersome to send two separate reverting patches. Should I? > >> Those commits cause regression on mt8173 elm device. The EC either is not >> able to register or it sends numerous amount of errors: > >> cros-ec-i2c-tunnel 1100a000.spi:ec@0:i2c-tunnel0: Error transferring EC i2c message -71 >> cros-ec-spi spi0.0: EC failed to respond in time. > > Do we have any analysis as to why? Do these devices use timing > parameters in some way for example, or do the values written out to the > device change in some way? > > You've provided no analysis here so it's hard to tell if this is just > some random change that happens to change code generation slighly or if > there's some actual reason why this might fix something. I'll note that > as far as I can see there are no users of this API upstream so I'm > guessing that you've got some out of tree consumer driver which uses the > API, it's possible that there was some error in updating that driver to > the new interface which is causing the issue. Actually the original commit not only change that callback 'set_cs_timing' but it also calls 'mtk_spi_set_hw_cs_timing' directly from the function "mtk_spi_prepare_message". So this actually influences all devices bound to this driver (in upstream) I did some printing and it does change values that are written to registers. Thanks, Dafna >