From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964779AbcJ0SGU (ORCPT ); Thu, 27 Oct 2016 14:06:20 -0400 Received: from mail-pf0-f175.google.com ([209.85.192.175]:33306 "EHLO mail-pf0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933792AbcJ0SGS (ORCPT ); Thu, 27 Oct 2016 14:06:18 -0400 Date: Thu, 27 Oct 2016 11:06:15 -0700 From: Matthias Kaehlcke To: "H. Nikolaus Schaller" Cc: linux-kernel@vger.kernel.org, Mark Brown , letux-kernel@openphoenux.org Subject: Re: [PATCH] regulator: core: silence warning: "VDD1: ramp_delay not set" Message-ID: <20161027180615.GA190727@google.com> References: <625675256c0d75805f088b4be17a3308dc1b7ea4.1477571498.git.hns@goldelico.com> <20161027174109.GA185131@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, El Thu, Oct 27, 2016 at 07:45:32PM +0200 H. Nikolaus Schaller ha dit: > > Am 27.10.2016 um 19:41 schrieb Matthias Kaehlcke : > > > > El Thu, Oct 27, 2016 at 02:31:39PM +0200 H. Nikolaus Schaller ha dit: > > > >> commit 73e705bf81ce ("regulator: core: Add set_voltage_time op") > >> > >> introduced a new rdev_warn() if the ramp_delay is 0. > >> > >> Apparently, on omap3/twl4030 platforms with dynamic voltage > >> management this results in non-ending spurious messages like > >> > >> [ 511.143066] VDD1: ramp_delay not set > >> [ 511.662322] VDD1: ramp_delay not set > >> [ 513.903625] VDD1: ramp_delay not set > >> [ 514.222198] VDD1: ramp_delay not set > >> [ 517.062835] VDD1: ramp_delay not set > >> [ 517.382568] VDD1: ramp_delay not set > >> [ 520.142791] VDD1: ramp_delay not set > >> [ 520.502593] VDD1: ramp_delay not set > >> [ 523.062896] VDD1: ramp_delay not set > >> [ 523.362701] VDD1: ramp_delay not set > >> [ 526.143035] VDD1: ramp_delay not set > >> > >> I have observed this on GTA04 while it is reported to occur on > >> N900 as well: https://bugzilla.kernel.org/show_bug.cgi?id=178371 > >> > >> This patch makes the warning appear only in debugging mode. > >> > >> Signed-off-by: H. Nikolaus Schaller > >> --- > >> drivers/regulator/core.c | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c > >> index 67426c0..5c1519b 100644 > >> --- a/drivers/regulator/core.c > >> +++ b/drivers/regulator/core.c > >> @@ -2754,7 +2754,7 @@ static int _regulator_set_voltage_time(struct regulator_dev *rdev, > >> ramp_delay = rdev->desc->ramp_delay; > >> > >> if (ramp_delay == 0) { > >> - rdev_warn(rdev, "ramp_delay not set\n"); > >> + rdev_dbg(rdev, "ramp_delay not set\n"); > >> return 0; > >> } > > > > Sorry about that, I didn't run into this since in my tests ramp_delay > > was set :( > > It may be that we have a rare exception. I didn't see it for example > on OMAP5 based boards. > > > > > Calling _regulator_set_voltage_time() with ramp_delay being zero is > > a common case, I think the message should be removed completely. > > I'd have no problem if it is a debug feature, that is why I proposed > to not completely remove it unconditionally. It shouldn't have been added in the first place, it stems from code that incorrectly assumes that the code path is only executed when ramp_delay is set. I removed the message from that code (d89564efe79419a093e966a959bf5ba2c94e693f "regulator: core: Don't skip set_voltage_time when ramp delay disabled"), but missed to remove/not add it in this function.