From patchwork Fri Feb 17 12:41:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudiu Beznea X-Patchwork-Id: 13144659 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 alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 70443C636D4 for ; Fri, 17 Feb 2023 12:43:43 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id A1A61F13; Fri, 17 Feb 2023 13:42:50 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz A1A61F13 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1676637820; bh=U2iLnm4KuI3Sgwn+ds9QR6hu9ocdgvXPg7MffzvqL48=; h=From:To:Subject:Date:CC:List-Id:List-Archive:List-Help:List-Owner: List-Post:List-Subscribe:List-Unsubscribe:From; b=Hlq2a98XYLomNZ/lNpRPOWdGrVYgNWPv3tHhqwgGjwqwtlRkRkIjPadjgiBZdE+ds qhhW9nmdttHu+Hrdv6PxL1gMscCLKfusoSL8eCKqCRx/g3RTNBoN5ADL9co2GFaKcL sL5io1pXNr+c2lKnJrjq8+TclhpFLgTZhNuuvdhw= Received: from mailman-core.alsa-project.org (mailman-core.alsa-project.org [10.254.200.10]) by alsa1.perex.cz (Postfix) with ESMTP id B32D3F801C0; Fri, 17 Feb 2023 13:42:24 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 242EFF801C0; Fri, 17 Feb 2023 13:42:20 +0100 (CET) Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 1D56BF800AA for ; Fri, 17 Feb 2023 13:42:09 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 1D56BF800AA Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key, unprotected) header.d=microchip.com header.i=@microchip.com header.a=rsa-sha256 header.s=mchp header.b=wrz/iJO0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1676637731; x=1708173731; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=U2iLnm4KuI3Sgwn+ds9QR6hu9ocdgvXPg7MffzvqL48=; b=wrz/iJO0r9nWyY6o/RptJCLgZ0s8cgWCm/Jk/ZPs9MUToyPFVWm1ca7D mI0p0SXuW7j5ep31wCDBYvFRjBSKdGaA1xgAh0hdbhS3jOsAeSLSceMjM iCnBYg2HCeY6p4s+MbGpPotWIbjzGtJK/ME7UpZR3GkLbeuL/Mtpk9OQ2 IxbQmtAtguaznKa5OsYaGzSzIY702AsX9DM7BObGUqwUQmtxh7w7YH5w6 jS9/kWqX6SWcuF4sqBgw01LHHSpRnNW1x1IGyf4xuAwtWXqdtFP5lPDFH 6NKCRWoNB9oRV5zyB6f+dKuAZCZpVqYpHn+qg+tFTVV36C2G1dh6vLFmU g==; X-IronPort-AV: E=Sophos;i="5.97,304,1669100400"; d="scan'208";a="137771389" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa6.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 17 Feb 2023 05:42:03 -0700 Received: from chn-vm-ex01.mchp-main.com (10.10.85.143) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16; Fri, 17 Feb 2023 05:42:03 -0700 Received: from m18063-ThinkPad-T460p.mchp-main.com (10.10.115.15) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server id 15.1.2507.16 via Frontend Transport; Fri, 17 Feb 2023 05:42:00 -0700 From: Claudiu Beznea To: , , , , , , , Subject: [PATCH v2 0/3] ASoC: mchp-pdmc: fix poc noises when starting capture Date: Fri, 17 Feb 2023 14:41:48 +0200 Message-ID: <20230217124151.236216-1-claudiu.beznea@microchip.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Message-ID-Hash: MRQ6C7HDF4VBU6ZV7HT457SMH2OIKGGD X-Message-ID-Hash: MRQ6C7HDF4VBU6ZV7HT457SMH2OIKGGD X-MailFrom: Claudiu.Beznea@microchip.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-alsa-devel.alsa-project.org-0; header-match-alsa-devel.alsa-project.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Claudiu Beznea X-Mailman-Version: 3.3.8 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: To start capture on Microchip PDMC the enable bits for each supported microphone need to be set. After this bit is set the PDMC starts to receive data from microphones and it considers this data as valid data. Thus if microphones are not ready the PDMC captures anyway data from its lines. This data is interpreted by the human ear as poc noises. To avoid this the following software workaround need to be applied when starting capture: 1/ enable PDMC channel 2/ wait 150ms 3/ execute 16 dummy reads from RHR 4/ clear interrupts 5/ enable interrupts 6/ enable DMA channel For this workaround to work step 6 need to be executed at the end. For step 6 was added patch 1/3 from this series. With this, component DAI driver sets its struct snd_soc_component_driver::start_dma_last = 1 and proper action is taken based on this flag when starting DAI trigger vs DMA. Thank you, Claudiu Beznea Changes in v2: - patch 1/3 from v1 is now "ASoC: soc-pcm: add option to start DMA after DAI" - pass start_dma_last from component DAI driver object (struct snd_soc_component_driver::start_dma_last); adapt patch 3/3 after this; - in patch 1/3 s/Do we need to start dma first/Do we need to start dma last in comment from soc_pcm_trigger() - collect review tag from Krzysztof Claudiu Beznea (3): ASoC: soc-pcm: add option to start DMA after DAI ASoC: dt-bindings: sama7g5-pdmc: add microchip,startup-delay-us binding ASoC: mchp-pdmc: fix poc noise at capture startup .../sound/microchip,sama7g5-pdmc.yaml | 6 ++ include/sound/soc-component.h | 2 + sound/soc/atmel/mchp-pdmc.c | 55 +++++++++++++++++-- sound/soc/soc-pcm.c | 27 +++++++-- 4 files changed, 80 insertions(+), 10 deletions(-)