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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 B23FCC388F7 for ; Tue, 10 Nov 2020 04:03:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B28B20663 for ; Tue, 10 Nov 2020 04:03:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="STXd2HFX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387584AbgKJEDm (ORCPT ); Mon, 9 Nov 2020 23:03:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:55734 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732819AbgKJDyo (ORCPT ); Mon, 9 Nov 2020 22:54:44 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4D30E207BC; Tue, 10 Nov 2020 03:54:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604980484; bh=lCSQVerc+jJ4Piycr3n5lNXAN1aByZZN2bWhfq7Vax4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=STXd2HFXNsagC0dTIZLsntmHKeaYMbj5m78gbGSOrBhvQj9BV9XnZNJQCy3n0EKMp +pUkKC5BNMxbd7dBCMin2Tl1w151Zw3+v+pEsK3P1ng0YIAzom+fc5BlT0D8XNMeHQ /2zX1rITEayGc4rl4Lrgu1CS/zkslzRVLwN4L1Hw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Olivier Moysan , Mark Brown , Sasha Levin , alsa-devel@alsa-project.org, patches@opensource.cirrus.com Subject: [PATCH AUTOSEL 5.4 02/42] ASoC: cs42l51: manage mclk shutdown delay Date: Mon, 9 Nov 2020 22:54:00 -0500 Message-Id: <20201110035440.424258-2-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201110035440.424258-1-sashal@kernel.org> References: <20201110035440.424258-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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[] = { -- 2.27.0