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=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_NEOMUTT 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 283B7C5CFFE for ; Mon, 10 Dec 2018 11:54:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DB8E720821 for ; Mon, 10 Dec 2018 11:54:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB8E720821 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727768AbeLJLyV (ORCPT ); Mon, 10 Dec 2018 06:54:21 -0500 Received: from foss.arm.com ([217.140.101.70]:52294 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727572AbeLJLyT (ORCPT ); Mon, 10 Dec 2018 06:54:19 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9CF4B15AB; Mon, 10 Dec 2018 03:54:18 -0800 (PST) Received: from queper01-lin (queper01-lin.cambridge.arm.com [10.1.195.48]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8D31B3F6A8; Mon, 10 Dec 2018 03:54:17 -0800 (PST) Date: Mon, 10 Dec 2018 11:54:13 +0000 From: Quentin Perret To: vireshk@kernel.org, nm@ti.com, sboyd@kernel.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] PM / OPP: Always expose one supply in debugfs Message-ID: <20181210115410.clyrxhp5plptrf5n@queper01-lin> References: <20181210113247.11412-1-quentin.perret@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181210113247.11412-1-quentin.perret@arm.com> User-Agent: NeoMutt/20171215 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday 10 Dec 2018 at 11:32:47 (+0000), Quentin Perret wrote: > On some platforms, the opp_table->regulator_count field is kept at zero > even though opp->supplies is always allocated. However, the loop used to > display the supplies in the debugfs doesn't deal correctly with this, > which results in the supplies not being displayed in debugfs on those > platforms. > > Fix this by making sure to always display at least once supply in > debugfs. > > Signed-off-by: Quentin Perret > > --- > > This has been observed on Juno r2 which uses SCPI and Hikey960 which > uses DT. I am not particularly familiar with that part of the code, so > I'm not sure if this is even remotely correct (hence the RFC tag). > > I first thought setting opp_table->regulator_count to 1 would be the > right fix but that causes other issues. This fix seems to work OK on > Juno and Hikey960, at least. > > Feedback is welcome :-) Hmm, so I just figured what I'm doing here is basically reverting: 1fae788ed640 ("PM / OPP: Don't create debugfs "supply-0" directory unnecessarily") Should I send a proper revert instead of this patch ? It _is_ handy to read voltage numbers when available. Thanks, Quentin > > Thanks, > Quentin > --- > drivers/opp/debugfs.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c > index e6828e5f81b0..2c14564575cb 100644 > --- a/drivers/opp/debugfs.c > +++ b/drivers/opp/debugfs.c > @@ -40,9 +40,9 @@ static bool opp_debug_create_supplies(struct dev_pm_opp *opp, > struct dentry *pdentry) > { > struct dentry *d; > - int i; > + int i = 0; > > - for (i = 0; i < opp_table->regulator_count; i++) { > + do { > char name[15]; > > snprintf(name, sizeof(name), "supply-%d", i); > @@ -68,7 +68,9 @@ static bool opp_debug_create_supplies(struct dev_pm_opp *opp, > if (!debugfs_create_ulong("u_amp", S_IRUGO, d, > &opp->supplies[i].u_amp)) > return false; > - } > + > + i++; > + } while (i < opp_table->regulator_count); > > return true; > } > -- > 2.19.2 >