From patchwork Tue Jun 25 15:07:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 13711496 Received: from mx07-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70F4716FF58; Tue, 25 Jun 2024 15:10:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.207.212.93 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719328212; cv=none; b=Tkkju/i1MpE4qjTeuZdZIlUg8AXfELvWITtmM1DpIsE95DUB7wIPZmeX9x3Xg/6aCHtIxLZKLv3chFdJNNKJuv6wpRZtZLtJgHPjWQXf1jrUQM7pUDl75AAJwuzzQ1rTPsqHYQljjedB2qHkYjyI/EAGIfTlp9YUdhtQjtyhmtA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719328212; c=relaxed/simple; bh=BluXeHwplUSe1CoPOTE9WTKDqlno0VegvObIVUK0mu0=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=CfttZPQJH1+GtNMfJnT69lvoPZf5vToYaS8Qhlmn/pbKEjUUS9clXfUXkV05AL36APAWpRxgOFZ4jGC5/W8sX0AIKB0w12JpRJhfIutgBtAgO9+wPwGZpwCwID6Sa9RRZSytyu7a/VdD0w5PSbQ8eGc+0IlVKkHsWvRU94J5kGQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com; spf=pass smtp.mailfrom=foss.st.com; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b=8RkTq0ig; arc=none smtp.client-ip=91.207.212.93 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="8RkTq0ig" Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 45PDMWtZ024615; Tue, 25 Jun 2024 17:09:38 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:message-id :mime-version:subject:to; s=selector1; bh=bXWNzZd00d3Wno9/beXi93 NETzadbrJvtUIR5akEHEQ=; b=8RkTq0igjgtyEMP6NGNT3YRxApOa+B8dyts+4i 1Red80n3tz6aQ4p4w0Dtj4P4MZn+iIS/Ux8UHYn7DyQR08t0n/24vyfrZMXOnzkO NdKh381MpLsJdKHEhONSY5uUQ8KoSD7uU9t09m2gpN6iaefoyDPwX1dXpSpPms3p SAms+gHpqLk5XCGeWa639xOAuRoDnjrUQHsGUkkNRTL7fnqghnDQGTlENyoQQyc8 19vvpw6Rj3hj46APcf5djh+TA09CfhIxWWpzBNdZh0+TrSFYc75FzmBvJMAnBxdq 4iS1nCsyJPp/cg6oT9qwdikcUCXj/F4yWiiZ5+h9xsp7Dk9Q== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3ywkr5cbyk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 25 Jun 2024 17:09:37 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id E13D540044; Tue, 25 Jun 2024 17:09:26 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 246242207A5; Tue, 25 Jun 2024 17:08:26 +0200 (CEST) Received: from localhost (10.252.26.63) by SHFDAG1NODE1.st.com (10.75.129.69) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Tue, 25 Jun 2024 17:08:25 +0200 From: Olivier Moysan To: , Jonathan Cameron , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Olivier Moysan , Arnaud Pouliquen , Maxime Coquelin , Alexandre Torgue , Nuno Sa , Liam Girdwood , Mark Brown CC: , , , , , Subject: [PATCH v2 0/8] iio: adc: dfsdm: add scaling support Date: Tue, 25 Jun 2024 17:07:08 +0200 Message-ID: <20240625150717.1038212-1-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EQNCAS1NODE3.st.com (10.75.129.80) To SHFDAG1NODE1.st.com (10.75.129.69) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-06-25_10,2024-06-25_01,2024-05-17_01 The aim of this serie is to add scaling support to STM32 DFSDM peripheral in the analog context. The DFSDM currently operates as a consumer of IIO channels provided by a generic SD modulator. As previously discussed in RFC [1], this topology is not suitable for implementing scaling. This series brings the integration of the DFSDM driver with the new IIO backend framework [2], enabling the DFSDM IIO device to offer scaling feature based on reference voltage data obtained from the IIO SD modulator backend. This generic SD modulator backend takes the place of the former SD modulator, used with legacy implementation. The DFSDM driver has been updated to adopt the generic ADC channel binding [3]. The reasons for this include: - Reducing the use of proprietary properties - Simplifying the coexistence of legacy and new backend bindings - Prepare the support of the MDF peripheral on STM32MP25 SoC Backward compatibility is maintained through legacy support. This series extends the backend framework with the following APIs: - iio_backend_read_raw: This API is intented to retrieve the voltage information from the backend. It is based on IIO framework read_raw API. - iio_backend_disable / iio_backend_enable: backend enable/disable to be used for PM management - devm_iio_backend_fwnode_get Intended for parsing DT subnodes to allow generic channel binding support, as generic channel DT nodes are not populated as devices. [1]: https://lore.kernel.org/lkml/20200204101008.11411-1-olivier.moysan@st.com/ [2]: https://lore.kernel.org/all/20240206-iio-backend-v9-0-df66d159c000@analog.com/ [3]: devicetree/bindings/iio/adc/adc.yaml Changes in v2: - Update enable/disable backend API - Rename devm_iio_backend_subnode_get(), as devm_iio_backend_fwnode_get() - Update iio_backend_read_raw() prototype to fully match IIO framework read_raw callback prototype. - Change st,adc-channel-type property name and type in DFSDM binding - Remove sd-backend and rename ads1201 compatibles in SD binding Conor, in this v2, I left the SD modulator driver & binding unchanged, regarding the naming issue you raised previously. The problem here is that we have two versions of the generic sigma delta modulator driver: one for legacy support and a new one to support new binding. Maybe an alternate, is to rename former sd modulator as "legacy" or something similar. I will address this point in a v3 if necessary. Olivier Moysan (8): iio: add read raw service to iio backend framework iio: add enable and disable services to iio backend framework iio: add child nodes support in iio backend framework dt-bindings: iio: dfsdm: move to backend framework dt-bindings: iio: add sigma delta modulator backend iio: adc: stm32-dfsdm: adopt generic channels bindings iio: add sd modulator generic iio backend iio: adc: stm32-dfsdm: add scaling support to dfsdm .../iio/adc/sd-modulator-backend.yaml | 39 +++ .../bindings/iio/adc/st,stm32-dfsdm-adc.yaml | 157 ++++++++- drivers/iio/adc/Kconfig | 11 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/sd_adc_backend.c | 117 +++++++ drivers/iio/adc/stm32-dfsdm-adc.c | 302 +++++++++++++++--- drivers/iio/industrialio-backend.c | 108 +++++-- include/linux/iio/backend.h | 10 +- 8 files changed, 679 insertions(+), 66 deletions(-) create mode 100644 Documentation/devicetree/bindings/iio/adc/sd-modulator-backend.yaml create mode 100644 drivers/iio/adc/sd_adc_backend.c base-commit: 2dfa1b7bfc07e58acb9f9eaa8c871f37189dbfee