Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751824AbdGZMGr (ORCPT ); Wed, 26 Jul 2017 08:06:47 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:33815 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751734AbdGZMGT (ORCPT ); Wed, 26 Jul 2017 08:06:19 -0400 Subject: Re: [PATCH v2 01/11] ASoC: samsung: s3c2412: Handle return value of clk_prepare_enable. To: Mark Brown References: <84c0014d4dbd466f52c45d8efbd2c1080d8174fb.1501047400.git.arvind.yadav.cs@gmail.com> <20170726112817.sdcfz25nhiitkhd2@sirena.org.uk> Cc: perex@perex.cz, tiwai@suse.com, krzk@kernel.org, sbkim73@samsung.com, lgirdwood@gmail.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org From: Arvind Yadav Message-ID: Date: Wed, 26 Jul 2017 17:35:32 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170726112817.sdcfz25nhiitkhd2@sirena.org.uk> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1862 Lines: 51 Hi, On Wednesday 26 July 2017 04:58 PM, Mark Brown wrote: > On Wed, Jul 26, 2017 at 11:15:25AM +0530, Arvind Yadav wrote: > >> --- a/sound/soc/samsung/s3c2412-i2s.c >> +++ b/sound/soc/samsung/s3c2412-i2s.c >> @@ -65,13 +65,16 @@ static int s3c2412_i2s_probe(struct snd_soc_dai *dai) >> s3c2412_i2s.iis_cclk = devm_clk_get(dai->dev, "i2sclk"); >> if (IS_ERR(s3c2412_i2s.iis_cclk)) { >> pr_err("failed to get i2sclk clock\n"); >> - return PTR_ERR(s3c2412_i2s.iis_cclk); >> + ret = PTR_ERR(s3c2412_i2s.iis_cclk); >> + goto err; >> } >> > Why are we making this unrelated change? None of the error handling we > jump to is relevant if this fails... 3c_i2sv2_probe is enabling "iis" clock. If devm_clk_get(, "i2sclk") fails. we need to disable and free the clock "iis" . > >> /* Set MPLL as the source for IIS CLK */ >> >> clk_set_parent(s3c2412_i2s.iis_cclk, clk_get(NULL, "mpll")); >> - clk_prepare_enable(s3c2412_i2s.iis_cclk); >> + ret = clk_prepare_enable(s3c2412_i2s.iis_cclk); >> + if (ret) >> + goto err; >> >> s3c2412_i2s.iis_cclk = s3c2412_i2s.iis_pclk; >> >> @@ -80,6 +83,11 @@ static int s3c2412_i2s_probe(struct snd_soc_dai *dai) >> S3C_GPIO_PULL_NONE); >> >> return 0; >> + >> +err: >> + clk_disable(s3c2412_i2s.iis_pclk); > This will disable the clock if we failed to enable it which is clearly > not correct. It's also matching a clk_prepare_enable() with a > clk_disable() which is going to leave an unbalanced prepare. s3c_i2sv2_probe is enabling "iis" clock. And s3c2412_i2s_probe is enabling "i2sclk" and "mpll"clock. If, "mpll" clk_prepare_enable fails. We need to disable and free the clock "iis". and devm will handle other clock "i2sclk". In this code we have used "s3c2412_i2s.iis_cclk" for all the clock which is more confusing for me. Please correct me if i am wrong. ~arvind