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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 690FDC282C8 for ; Mon, 28 Jan 2019 11:26:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41F60214DA for ; Mon, 28 Jan 2019 11:26:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726738AbfA1L0w (ORCPT ); Mon, 28 Jan 2019 06:26:52 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:37657 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726415AbfA1L0w (ORCPT ); Mon, 28 Jan 2019 06:26:52 -0500 Received: from lupine.hi.pengutronix.de ([2001:67c:670:100:3ad5:47ff:feaf:1a17] helo=lupine) by metis.ext.pengutronix.de with esmtp (Exim 4.89) (envelope-from ) id 1go53w-0004ZZ-ET; Mon, 28 Jan 2019 12:26:48 +0100 Message-ID: <1548674808.6421.3.camel@pengutronix.de> Subject: Re: [PATCH] reset: Don't WARN if trying to get a used reset control From: Philipp Zabel To: Thierry Reding Cc: Jon Hunter , linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 28 Jan 2019 12:26:48 +0100 In-Reply-To: <20190125101554.5947-1-thierry.reding@gmail.com> References: <20190125101554.5947-1-thierry.reding@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:100:3ad5:47ff:feaf:1a17 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thierry, On Fri, 2019-01-25 at 11:15 +0100, Thierry Reding wrote: > From: Thierry Reding > > When requesting a reset control for exclusive use that's already in use, > an -EBUSY error code is returned. Users can react accordingly when they > receive that error code, so there is no need to loudly complain. > > Signed-off-by: Thierry Reding > --- > drivers/reset/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/reset/core.c b/drivers/reset/core.c > index 9582efb70025..6b452f010b66 100644 > --- a/drivers/reset/core.c > +++ b/drivers/reset/core.c > @@ -416,7 +416,7 @@ static struct reset_control *__reset_control_get_internal( > > list_for_each_entry(rstc, &rcdev->reset_control_head, list) { > if (rstc->id == index) { > - if (WARN_ON(!rstc->shared || !shared)) > + if (!rstc->shared || !shared) > return ERR_PTR(-EBUSY); > > kref_get(&rstc->refcnt); Are you actually running into this somewhere? My reason for adding these warnings was that these point to either a DT misconfiguration or a driver bug, and the verbose warning helps to quickly identify the actual issue. This is not an error condition that I would expect on a correctly configured system. I don't expect most drivers give a proper error message that contains the -EBUSY return value. Usually it's just along the lines of "failed to get reset control" without any further indication. regards Philipp