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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 EA61CC54FC9 for ; Tue, 21 Apr 2020 18:20:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0AD520679 for ; Tue, 21 Apr 2020 18:20:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729320AbgDUSUY (ORCPT ); Tue, 21 Apr 2020 14:20:24 -0400 Received: from muru.com ([72.249.23.125]:50780 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726628AbgDUSUX (ORCPT ); Tue, 21 Apr 2020 14:20:23 -0400 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id DC8B98081; Tue, 21 Apr 2020 18:21:08 +0000 (UTC) Date: Tue, 21 Apr 2020 11:20:17 -0700 From: Tony Lindgren To: "H. Nikolaus Schaller" Cc: Andreas Kemnade , Evgeniy Polyakov , Greg Kroah-Hartman , Linux Kernel Mailing List , linux-omap , Adam Ford , "Andrew F . Davis" , Vignesh R Subject: Re: [PATCHv3] w1: omap-hdq: Simplify driver with PM runtime autosuspend Message-ID: <20200421182017.GC37466@atomide.com> References: <3197C3F0-DEB9-4221-AFBD-4F2A08C84C4C@goldelico.com> <20200417164340.3d9043d1@aktux> <6430AF54-849E-456B-8DB0-B4478BBDB78D@goldelico.com> <20200417150721.GL37466@atomide.com> <8E062482-5D5D-4837-9980-D6C708DD24D4@goldelico.com> <20200420150802.GR37466@atomide.com> <20200421085336.32cf8ffe@aktux> <20200421180220.GB37466@atomide.com> <70F19A6E-7B36-4873-9364-F284A14EE3A0@goldelico.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <70F19A6E-7B36-4873-9364-F284A14EE3A0@goldelico.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * H. Nikolaus Schaller [200421 18:14]: > > Am 21.04.2020 um 20:02 schrieb Tony Lindgren : > > This is 37xx though, maybe you have 35xx and there's some errata > > that we're not handling? > > No, it is dm3730 on three different units I have tried. > > > I'm only seeing "2.7. HDQTM/1-Wire® Communication Constraints" > > for external pull-up resitor in 34xx errata at [0]. > > > > I wonder if wrong external pull could cause flakyeness after > > enabling the hdq module? > > I have checked and we have 10 kOhm pullup to 1.8 V and a 470 Ohm > series resistor. OK > > If nothing else helps, you could try to block idle for hdq > > module, but I have a feeling that's a workaround for something > > else. > > Well, what helps is reverting the patch and using the old driver > (which did work for several years). So I would not assume that > there is a hardware influence. It seems to be something the new > driver is doing differently. Well earlier hdq1w.c did not idle, now it does. If you just want to keep it enabled like earlier, you can just add something like: &hdqw1w { ti,no-idle; }; > I need more time to understand and trace this issue on what it > depends... It may depend on the sequence some other modules are > loaded and what the user-space (udevd) is doing in the meantime. Yes would be good to understand what goes wrong here before we apply the ti,no-idle as that will block SoC deeper idle states. Regards, Tony