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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61ABAC433EF for ; Fri, 4 Mar 2022 14:40:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239834AbiCDOlW (ORCPT ); Fri, 4 Mar 2022 09:41:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237280AbiCDOlT (ORCPT ); Fri, 4 Mar 2022 09:41:19 -0500 Received: from mx0b-001ae601.pphosted.com (mx0b-001ae601.pphosted.com [67.231.152.168]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 027F11BBF75 for ; Fri, 4 Mar 2022 06:40:30 -0800 (PST) Received: from pps.filterd (m0077474.ppops.net [127.0.0.1]) by mx0b-001ae601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 2248TIlJ019088; Fri, 4 Mar 2022 08:40:18 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=PODMain02222019; bh=bFhXLBMGqICJ9xa4zHe1IgD/QVmyIzhRYAhGIXcq0CU=; b=dxXP/m1O4qV6f6lgFmV2P9GFp126XRrB7ogHV29TDLnxAW703vhrcpSkq7bSlvjkd4Z3 wV9FhLfji9kDnbyhPHkuyOGLVG/BlWr0W8m6gNi4Jplax4E/jKF39+CvkjKG9W/Uf+h+ zX8Cag0MDQLxGWhKc6co1l7Stfe5NtelgR38k9pAdDwZehoGUdg8t4QlSE8yF/sdM6/G EX2a0rtTo8IFhkicBw3f717cUu5kwQkHp5uPebwbKp0bOZqq53NjgZWIXm4AQmdkUgxM XJL6ZxlOoiPejG/uH2gUxmZMNw8i7ahho/0Eljd3mMGjQF6lyPEUqxoTyXYY4nJmJtlp bA== Received: from ediex02.ad.cirrus.com ([84.19.233.68]) by mx0b-001ae601.pphosted.com (PPS) with ESMTPS id 3ek4j3h2td-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Fri, 04 Mar 2022 08:40:18 -0600 Received: from EDIEX01.ad.cirrus.com (198.61.84.80) by EDIEX02.ad.cirrus.com (198.61.84.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.18; Fri, 4 Mar 2022 14:40:17 +0000 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by EDIEX01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server id 15.1.2375.18 via Frontend Transport; Fri, 4 Mar 2022 14:40:17 +0000 Received: from AUSNPC0LSNW1-debian.ad.cirrus.com (AUSNPC0LSNW1.ad.cirrus.com [198.90.251.79]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id 36C747C; Fri, 4 Mar 2022 14:40:17 +0000 (UTC) From: Richard Fitzgerald To: CC: , , , Richard Fitzgerald Subject: [PATCH] ASoC: cs42l42: Add warnings about DETECT_MODE and PLL_START Date: Fri, 4 Mar 2022 14:40:15 +0000 Message-ID: <20220304144015.398656-1-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Proofpoint-GUID: alberyu2hsG-jYvJnT3dm0fL5Q1eubXO X-Proofpoint-ORIG-GUID: alberyu2hsG-jYvJnT3dm0fL5Q1eubXO X-Proofpoint-Spam-Reason: safe Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org DETECT_MODE and PLL_START must be zero while HP_PDN and ADC_PDN are both 1. If this condition is broken it can discharge FILT+ and it can then take up to 1 second for FILT+ to recharge. There is no workaround required for this, simply avoiding settings and sequences that would break the requirement. The driver already meets the requirement. But it is not obvious from reading the code that this requirement exists, or what is ensuring it is met. So it would not currently be obvious to someone changing the code that there is certain special behaviour that must be maintained. To avoid accidental breakage in the future: - Add comments into the register definitions to warn about this so that anyone changing the code around DETECT_MODE and PLL_START is aware of this requirement. - Add a comment where PLL_START is written to 1 to highlight the requirement and why it is satisfied. - Add a comment in cs42l42_setup_hs_type_detect() when DETECT_MODE is initialized. Signed-off-by: Richard Fitzgerald --- sound/soc/codecs/cs42l42.c | 13 ++++++++++++- sound/soc/codecs/cs42l42.h | 9 ++++++++- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c index db6ef6cdce15..c8409d50e934 100644 --- a/sound/soc/codecs/cs42l42.c +++ b/sound/soc/codecs/cs42l42.c @@ -1012,7 +1012,14 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream) } } else { if (!cs42l42->stream_use) { - /* SCLK must be running before codec unmute */ + /* SCLK must be running before codec unmute. + * + * PLL must not be started with ADC and HP both off + * otherwise the FILT+ supply will not charge properly. + * DAPM widgets power-up before stream unmute so at least + * one of the "DAC" or "ADC" widgets will already have + * powered-up. + */ if (pll_ratio_table[cs42l42->pll_config].mclk_src_sel) { snd_soc_component_update_bits(component, CS42L42_PLL_CTL1, CS42L42_PLL_START_MASK, 1); @@ -1830,6 +1837,10 @@ static void cs42l42_setup_hs_type_detect(struct cs42l42_private *cs42l42) cs42l42->hs_type = CS42L42_PLUG_INVALID; + /* + * DETECT_MODE must always be 0 with ADC and HP both off otherwise the + * FILT+ supply will not charge properly. + */ regmap_update_bits(cs42l42->regmap, CS42L42_MISC_DET_CTL, CS42L42_DETECT_MODE_MASK, 0); diff --git a/sound/soc/codecs/cs42l42.h b/sound/soc/codecs/cs42l42.h index 244b24d1f5e9..60d3bdf5d7c9 100644 --- a/sound/soc/codecs/cs42l42.h +++ b/sound/soc/codecs/cs42l42.h @@ -491,7 +491,10 @@ #define CS42L42_TS_UNPLUG 0 #define CS42L42_TS_TRANS 1 -/* Page 0x15 Fractional-N PLL Registers */ +/* + * NOTE: PLL_START must be 0 while both ADC_PDN=1 and HP_PDN=1. + * Otherwise it will prevent FILT+ from charging properly. + */ #define CS42L42_PLL_CTL1 (CS42L42_PAGE_15 + 0x01) #define CS42L42_PLL_START_SHIFT 0 #define CS42L42_PLL_START_MASK (1 << CS42L42_PLL_START_SHIFT) @@ -574,6 +577,10 @@ #define CS42L42_TIP_SENSE_CTRL_MASK (3 << \ CS42L42_TIP_SENSE_CTRL_SHIFT) +/* + * NOTE: DETECT_MODE must be 0 while both ADC_PDN=1 and HP_PDN=1. + * Otherwise it will prevent FILT+ from charging properly. + */ #define CS42L42_MISC_DET_CTL (CS42L42_PAGE_1B + 0x74) #define CS42L42_PDN_MIC_LVL_DET_SHIFT 0 #define CS42L42_PDN_MIC_LVL_DET_MASK (1 << CS42L42_PDN_MIC_LVL_DET_SHIFT) -- 2.30.2