From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765919AbdEXByy (ORCPT ); Tue, 23 May 2017 21:54:54 -0400 Received: from mailout3.samsung.com ([203.254.224.33]:58331 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751905AbdEXByr (ORCPT ); Tue, 23 May 2017 21:54:47 -0400 X-AuditID: b6c32a38-f791a6d0000031eb-89-5924e7e54aef MIME-version: 1.0 Content-transfer-encoding: 8BIT Content-type: text/plain; charset="utf-8" Message-id: <5924E7E4.5020900@samsung.com> Date: Wed, 24 May 2017 10:54:44 +0900 From: Chanwoo Choi Organization: Samsung Electronics User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 To: myungjoo.ham@samsung.com, Arvind Yadav , Kyungmin Park , "krzk@kernel.org" , "kgene@kernel.org" , "javier@osg.samsung.com" Cc: "linux-pm@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-samsung-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v1] PM / devfreq: exynos-ppmu : Handle return value of clk_prepare_enable In-reply-to: <20170524013036epcms1p3f5ced11e6ebe5664ce70718dedcf8de1@epcms1p3> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrBJsWRmVeSWpSXmKPExsWy7bCmvu7T5yqRBit2clhc613IbPHm7Rom i/7Hr5ktzp/fwG5xtukNu8Wmx9dYLS7vmsNm8bn3CKPFjPP7mCxuN65gc+Dy2DnrLrvHplWd bB6bl9R7bOkH8vq2rGL0+LxJLoAtKtUmIzUxJbVIITUvOT8lMy/dVsk7ON453tTMwFDX0NLC XEkhLzE31VbJxSdA1y0zB+gyJYWyxJxSoFBAYnGxkr6dTVF+aUmqQkZ+cYmtUrShoZGeoYG5 npGRkZ6JcayVkSlQSUJqxrEtq5kKPnBXnDo6ibWB8QVnFyMnh4SAiUTzy79sELaYxIV768Fs IYEdjBKP33F0MXIB2Z8ZJZ68nM8G0zD3/HpmiMRaRokXC+YxgiR4BQQlfky+x9LFyMHBLCAv ceRSNkiYWUBT4sWXSSwQ9fcYJT58u84MUa8lMefqX7BeFgFVib7zDawgNhtQfP+LG2DL+AUU Ja7+eAxWIyoQIbFz/jd2kEEiAt8YJWb1PmUCcZgFZjBJND7+xgRSJSwQL7F9XwcLiM0p4Cdx 7PV9sFMlBPaxS7xtX8MGcp6EgKzEpgPMEO+4SDxb0sIEYQtLvDq+hR3ClpJofPmQCaK3nVFi 85x7LBBOB6PE/ZWNrBBVxhKnuhqZIB7lk3j3tYcVYgGvREebEESJh8Ti1n/QsHOU+Lz1GjTs gF54P/0Y2wRGhVlIwTcLEXyzkIJvASPzKkax1ILi3PTUYsMCE73ixNzi0rx0veT83E2M4FSq ZbGDcc85n0OMAhyMSjy8E7aqRAqxJpYVV+YeYpTgYFYS4V2+ASjEm5JYWZValB9fVJqTWnyI 0RQY+hOZpUST84FpPq8k3tDE0sDEzAiY8CwNDZXEeUXXX4sQEkhPLEnNTk0tSC2C6WPi4JRq YLSJrHhuzc+/tGBCXmTPL92w8stli+ScjDomrVth6NpnN/ev26WT7ys+X3vkw1tzaM7Wq+8l Ni59sVEs9pzbnuzj/X6/L7Q6hBwx3r7l1dSrWscvJV9KsZZ8a/ps2a9rIdmy8ZLxQZ42Sz8n 9YR2TZNqXXE0XbVbW0+CLSj9dHOEe+Ck9Xt31CixFGckGmoxFxUnAgCLexi0uwMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrMIsWRmVeSWpSXmKPExsVy+t9jQd0nz1UiDa4tMLS41ruQ2eLN2zVM Fv2PXzNbnD+/gd3ibNMbdotNj6+xWlzeNYfN4nPvEUaLGef3MVncblzB5sDlsXPWXXaPTas6 2Tw2L6n32NIP5PVtWcXo8XmTXABblJtNRmpiSmqRQmpecn5KZl66rVJoiJuuhZJCXmJuqq1S hK5vSJCSQlliTimQZ2SABhycA9yDlfTtEtwyjm1ZzVTwgbvi1NFJrA2MLzi7GDk5JARMJOae X88MYYtJXLi3ng3EFhJYzSgx/YM0iM0rICjxY/I9li5GDg5mAXmJI5eyIUx1iSlTcrsYuYCq HzBK7Fv1iBGiXEtiztW/YDaLgKpE3/kGVhCbDSi+/8UNsPH8AooSV388ZgSZIyoQIdF9ohJk jojAN0aJN9OWM4M4zALTmCTuzZ4C1iAsEC+xfV8HC8Q2oKo/F86AbeAU8JM49vo+8wRGwVlI bp2FcOsshFsXMDKvYuRKLSjOTc8tNiow3MQIjMBth7X8dzD+OBt9iFGAg1GJh/dHlUqkEGti WXFl7iFGCQ5mJRHe5RuAQrwpiZVVqUX58UWlOanFhxhNgd6byCwlmpwPTA55JfGGJpZGJgZm ZoZGBsZmSuK8EwK/RAgJpCeWpGanphakFsH0MXFwSjUwtl3Rapx7MO+3qu9P6cdv35eezref wdOrOpl34T7WrqATy5UvKHH6TPlsax1fGvXBojL6UFe4/nOBc9N5/85g2mpup/m+oS828mvJ ykTJ5Fyfls2tDJeyDHoZrzVen3X254fdHyL2fn3iXX9Z78Ee9qebJwrHToxWPx1+2/Kskp2M 0/f7jU9ilViKMxINtZiLihMB5lh9ytYCAAA= X-MTR: 20000000000000000@CPGS X-CMS-MailID: 20170524015444epcas1p4a788ef84ad66be9ad3e0c490240f07fe X-Msg-Generator: CA X-Sender-IP: 182.195.42.79 X-Local-Sender: =?UTF-8?B?7LWc7LCs7JqwG1RpemVuIFBsYXRmb3JtIExhYihTL1fshLw=?= =?UTF-8?B?7YSwKRvsgrzshLHsoITsnpAbU2VuaW9yIEVuZ2luZWVy?= X-Global-Sender: =?UTF-8?B?Q2hhbndvbyBDaG9pG1RpemVuIFBsYXRmb3JtIExhYi4bU2Ft?= =?UTF-8?B?c3VuZyBFbGVjdHJvbmljcxtTZW5pb3IgRW5naW5lZXI=?= X-Sender-Code: =?UTF-8?B?QzEwG1RFTEUbQzEwVjgxMTE=?= CMS-TYPE: 101P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20170519105745epcas5p29a5cbb259cd15138d7220f34e130e00a X-RootMTR: 20170519105745epcas5p29a5cbb259cd15138d7220f34e130e00a References: <592403E7.8060906@samsung.com> <1495191364-16015-1-git-send-email-arvind.yadav.cs@gmail.com> <20170524013036epcms1p3f5ced11e6ebe5664ce70718dedcf8de1@epcms1p3> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017년 05월 24일 10:30, MyungJoo Ham wrote: >> On 2017년 05월 19일 19:56, Arvind Yadav wrote: >>> clk_prepare_enable() can fail here and we must check its return value. >>> >>> Signed-off-by: Arvind Yadav >>> --- >>> drivers/devfreq/event/exynos-ppmu.c | 6 +++++- >>> 1 file changed, 5 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c >>> index 9b73509..8f6537a 100644 >>> --- a/drivers/devfreq/event/exynos-ppmu.c >>> +++ b/drivers/devfreq/event/exynos-ppmu.c >>> @@ -648,7 +648,11 @@ static int exynos_ppmu_probe(struct platform_device *pdev) >>> dev_name(&pdev->dev), desc[i].name); >>> } >>> >>> - clk_prepare_enable(info->ppmu.clk); >>> + ret = clk_prepare_enable(info->ppmu.clk); >>> + if (ret) { >>> + dev_err(&pdev->dev, "failed to prepare ppmu clock\n"); >>> + return ret; >>> + } >> >> You're right. But, actually, some ppmu device-tree node doesn't include >> the clock information because exynos clk driver don't support the >> clock for some ppmu devices. Until now, the clock of ppmu devices >> are default on state. > > If it does not include the clock information, info->ppmu.clk is NULL, > which makes ret == NULL, so this should be ok. > (Line 593 of this file does that.) Ah.. You're right. I'm missing this point. Looks good to me. Acked-by: Chanwoo Choi -- Best Regards, Chanwoo Choi Samsung Electronics