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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 5981EC3A5A4 for ; Tue, 27 Aug 2019 16:45:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37FA921881 for ; Tue, 27 Aug 2019 16:45:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729626AbfH0Qpn (ORCPT ); Tue, 27 Aug 2019 12:45:43 -0400 Received: from muru.com ([72.249.23.125]:58862 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726610AbfH0Qpm (ORCPT ); Tue, 27 Aug 2019 12:45:42 -0400 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id A860C8107; Tue, 27 Aug 2019 16:46:10 +0000 (UTC) Date: Tue, 27 Aug 2019 09:45:38 -0700 From: Tony Lindgren To: Dan Murphy Cc: Pavel Machek , jacek.anaszewski@gmail.com, sre@kernel.org, nekit1000@gmail.com, mpartap@gmx.net, merlijn@wizzup.org, linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/5] leds: lm3532: Fix brightness control for i2c mode Message-ID: <20190827164538.GB52127@atomide.com> References: <20190820195307.27590-1-dmurphy@ti.com> <20190826215822.GY52127@atomide.com> <20190826221413.GA19124@amd> <20190826224437.GZ52127@atomide.com> <20190827121818.GB19927@amd> <0eab6f72-ddb7-3da7-e90e-888374531f86@ti.com> <9939e253-0c9e-5ef7-e160-c1e5fe99c453@ti.com> <20190827160454.GA52127@atomide.com> <56200c16-dcfe-3b14-6f22-80e5a387a66b@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <56200c16-dcfe-3b14-6f22-80e5a387a66b@ti.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-leds-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org * Dan Murphy [190827 16:20]: > Tony > > On 8/27/19 11:04 AM, Tony Lindgren wrote: > > * Dan Murphy [190827 13:02]: > > > Hello > > > > > > On 8/27/19 7:44 AM, Dan Murphy wrote: > > > > Tony > > > > > > > > On 8/27/19 7:18 AM, Pavel Machek wrote: > > > > > On Mon 2019-08-26 15:44:37, Tony Lindgren wrote: > > > > > > * Pavel Machek [190826 22:14]: > > > > > > > On Mon 2019-08-26 14:58:22, Tony Lindgren wrote: > > > > > > > > Hi, > > > > > > > > > > > > > > > > * Dan Murphy [190820 19:53]: > > > > > > > > > Fix the brightness control for I2C mode.  Instead of > > > > > > > > > changing the full scale current register update the ALS target > > > > > > > > > register for the appropriate banks. > > > > > > > > > > > > > > > > > > In addition clean up some code errors and random misspellings found > > > > > > > > > during coding. > > > > > > > > > > > > > > > > > > Tested on Droid4 as well as LM3532 EVM connected to > > > > > > > > > a BeagleBoneBlack > > > > > > > > > > > > > > > > > > Fixes: e37a7f8d77e1 ("leds: lm3532: Introduce the > > > > > > > > > lm3532 LED driver") > > > > > > > > > Reported-by: Pavel Machek > > > > > > > > > Signed-off-by: Dan Murphy > > > > > > > > > --- > > > > > > > > > > > > > > > > > > v3 - Removed register define updates - > > > > > > > > > https://lore.kernel.org/patchwork/patch/1114542/ > > > > > > > > Looks like starting with this patch in Linux next the LCD on droid4 > > > > > > > > is so dim it's unreadable even with brightness set to 255. Setting > > > > > > > > brightness to 0 does blank it completely though. > > > > > > > > > > > > > > > > Did something maybe break with the various patch revisions or are > > > > > > > > we now missing some dts patch? > > > > > > > Maybe missing dts patch. We should provide maximum current the LED can > > > > > > > handle... > > > > > > Or i2c control is somehow broken and only als control now works? > > > > With only setting CONFIG_LEDS_LM3532=m to the next branch I get full > > > > brightness with 255. > > > > > > > > I also see half brightness at 128 with the ramp down working. > > > > > > > > I am not able to reproduce this issue on my device. > > > > > > > Just to make sure my data was right I did a clean rebuild on commit > > > 1dbb9fb4082ce2a2f1cf9596881ddece062d15d0 > > > > > > from the led-next branch. > > > > > > Just adding the above config flag.  I still cannot reproduce the issue > > > > > > See attached pic > > OK thanks for checking. Probably you can reproduce the issue if you > > reset things to commit c4b8354e5341 ("leds: lm3532: Fix brightness > > control for i2c mode"). There might now be something uninitialized > > with that commit depending on the hardware state on boot if you > > care to check that. Or maybe there's some interaction with other > > patches not yet at commit c4b8354e5341 level. > > Ok the fix for that issue is in this patch > > leds: lm3532: Fixes for the driver for stability > > The fix for setting the brightness control register during the init forced > the ALS mode to > > be enabled.  The Fixes for driver stability patch then set the led->mode to > the correct register setting. OK yeah so that part starts to make sense now. I wonder if the reason for my issues was caused by change in sysfs brightness level values and I ended up chasing an already fixed issue. I think I was using value of 30 recently, which is now very dim :) > > I confirmed again that things fail at commit c4b8354e5341. But > > now testing with the same Linux next as yesterday things works again. > > Not sure what's going on as failures with Linux next yestreday > > made me start narrowing down what commit causes the issues. > > > > Anyways, playing with loading and unloading the leds-lm3532.ko I > > noticed we can also have unpaired regulator calls when using sysfs > > brightness that the below patch attempts to fix. Not sure how I got > > to the point of regulator warnings, but I was trying to enable > > the brightness via sysfs. Maybe I had other patches too when > > I got the regulator warnings.. But please check if the below > > patch makes sense. > > Makes sense did you want me to push a patch? No need to, I can send out a proper patch later today after typing up the patch description if no other comments. Regards, Tony