From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chanwoo Choi Subject: Re: [PATCH v1] PM / devfreq: exynos-ppmu : Handle return value of clk_prepare_enable Date: Wed, 24 May 2017 10:54:44 +0900 Message-ID: <5924E7E4.5020900@samsung.com> References: <592403E7.8060906@samsung.com> <1495191364-16015-1-git-send-email-arvind.yadav.cs@gmail.com> <20170524013036epcms1p3f5ced11e6ebe5664ce70718dedcf8de1@epcms1p3> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Return-path: 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 In-reply-to: <20170524013036epcms1p3f5ced11e6ebe5664ce70718dedcf8de1@epcms1p3> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org 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" 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