From patchwork Tue Nov 17 13:04:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 325361 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 55CADC5519F for ; Tue, 17 Nov 2020 13:24:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 092442464E for ; Tue, 17 Nov 2020 13:24:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Cl/6LlzE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730991AbgKQNYY (ORCPT ); Tue, 17 Nov 2020 08:24:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:59342 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730386AbgKQNYU (ORCPT ); Tue, 17 Nov 2020 08:24:20 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4F4FB2463D; Tue, 17 Nov 2020 13:24:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605619460; bh=lCSQVerc+jJ4Piycr3n5lNXAN1aByZZN2bWhfq7Vax4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cl/6LlzEFPPexY0rETDLm0n0UESKBNsweui693MREW+SpMWx6Yx1DlmAF6Ui1lHBW OJ71ufnLi34nm+osYR54ym16hdojkapdzafIM1BUSNvfoI3oksf8JMTz+f/QkuOL4r nsXxn3NPFn/zQVm/SaPe/EtBUzOA2FHMzdQYEZSc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Olivier Moysan , Mark Brown , Sasha Levin Subject: [PATCH 5.4 047/151] ASoC: cs42l51: manage mclk shutdown delay Date: Tue, 17 Nov 2020 14:04:37 +0100 Message-Id: <20201117122123.717745008@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122121.381905960@linuxfoundation.org> References: <20201117122121.381905960@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Olivier Moysan [ Upstream commit 20afe581c9b980848ad097c4d54dde9bec7593ef ] A delay must be introduced before the shutdown down of the mclk, as stated in CS42L51 datasheet. Otherwise the codec may produce some noise after the end of DAPM power down sequence. The delay between DAC and CLOCK_SUPPLY widgets is too short. Add a delay in mclk shutdown request to manage the shutdown delay explicitly. From experiments, at least 10ms delay is necessary. Set delay to 20ms as recommended in Documentation/timers/timers-howto.rst when using msleep(). Signed-off-by: Olivier Moysan Link: https://lore.kernel.org/r/20201020150109.482-1-olivier.moysan@st.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- sound/soc/codecs/cs42l51.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/sound/soc/codecs/cs42l51.c b/sound/soc/codecs/cs42l51.c index 55408c8fcb4e3..cdd7ae90c2b59 100644 --- a/sound/soc/codecs/cs42l51.c +++ b/sound/soc/codecs/cs42l51.c @@ -247,8 +247,28 @@ static const struct snd_soc_dapm_widget cs42l51_dapm_widgets[] = { &cs42l51_adcr_mux_controls), }; +static int mclk_event(struct snd_soc_dapm_widget *w, + struct snd_kcontrol *kcontrol, int event) +{ + struct snd_soc_component *comp = snd_soc_dapm_to_component(w->dapm); + struct cs42l51_private *cs42l51 = snd_soc_component_get_drvdata(comp); + + switch (event) { + case SND_SOC_DAPM_PRE_PMU: + return clk_prepare_enable(cs42l51->mclk_handle); + case SND_SOC_DAPM_POST_PMD: + /* Delay mclk shutdown to fulfill power-down sequence requirements */ + msleep(20); + clk_disable_unprepare(cs42l51->mclk_handle); + break; + } + + return 0; +} + static const struct snd_soc_dapm_widget cs42l51_dapm_mclk_widgets[] = { - SND_SOC_DAPM_CLOCK_SUPPLY("MCLK") + SND_SOC_DAPM_SUPPLY("MCLK", SND_SOC_NOPM, 0, 0, mclk_event, + SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD), }; static const struct snd_soc_dapm_route cs42l51_routes[] = {