From patchwork Wed Jul 3 16:05:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 1956346 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=foss.st.com header.i=@foss.st.com header.a=rsa-sha256 header.s=selector1 header.b=JttkfYrF; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=139.178.88.99; helo=sv.mirrors.kernel.org; envelope-from=devicetree+bounces-82923-incoming-dt=patchwork.ozlabs.org@vger.kernel.org; receiver=patchwork.ozlabs.org) Received: from sv.mirrors.kernel.org (sv.mirrors.kernel.org [139.178.88.99]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WDl930N7Xz1xqm for ; Thu, 4 Jul 2024 02:09:43 +1000 (AEST) Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id A8BA0289ED7 for ; Wed, 3 Jul 2024 16:09:41 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D09AF1849ED; Wed, 3 Jul 2024 16:08:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="JttkfYrF" X-Original-To: devicetree@vger.kernel.org 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 C866F1849D8; Wed, 3 Jul 2024 16:08:44 +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=1720022926; cv=none; b=j7kA/czvBEhO+SKCZcL0PihFtazZN4eQB1fiZ+/N8mWt6pYRy33m1U1rf3Mf1nRcAWQOm9JNwSv34HlmgDO+bCypexcOEXYgMN/FbInJiOIumtguG90SfsYZswOZobAQucFw0EsCsN0r2MEzLkwnPQ1lJzwk+wWr3c7EXLWLpbo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720022926; c=relaxed/simple; bh=uKJH5a0+6vkjwBTaDOSOxhl4qQyveqQZPb1wba4xWXQ=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=WB3kHdHvccqIytfYRcZGjS+mdkjOHz2p8F5e4Q+iPEfkMrI3+QrbHxmp8PmkboeVB/eDjwn5TpwmAdXRwMETpesInXNTZQkgJ9Fk9A482pBvJI4qdSsem/1GULve5nWrfVhgATpdKso7xnYgbkOLf/fe5Y6nUaryo8oiBSjloQk= 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=JttkfYrF; 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 Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 463FZQDU007347; Wed, 3 Jul 2024 18:08:24 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= Tv/R5KXfBaoQyssH47WsyM3KwW77pZ8ZcYwk4SeudZg=; b=JttkfYrF1XP9U7HI W7tIBo7IKtMzzaE88D5B11uJ/Uh6rUiwrBqEOeRcgMGqVNZi0zQp09xwU1OqJeBD 9M4J8SudnYuZM82FzmSQbTsQUXGppzYiEp3pZp2X7bULM8tbTqssEpY4BcaZ2VVY VwWJ/Dt2KVKLOLkQVFlSF7K8ATP0pDFOm2DcXXDGecq4QrUrsDryVqHYe2t3ppGR /rMNHXSQjOvCVSyVKGDzOQzCn8zREVLH5g9ECoaf3TAPjpCH901ADmQN7gEo5h3m tCENzykHL9J5wL7DSlmHNKPPTcf6T6AQ3k/pkwzNU7mazGAaDvL17djyGvG7VLoO GoC7+g== 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 40295dhfja-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 03 Jul 2024 18:08:23 +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 001D240049; Wed, 3 Jul 2024 18:08:19 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 994412291B0; Wed, 3 Jul 2024 18:07:30 +0200 (CEST) Received: from localhost (10.252.27.110) 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; Wed, 3 Jul 2024 18:07:30 +0200 From: Olivier Moysan To: Olivier Moysan , Arnaud Pouliquen , Jonathan Cameron , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Maxime Coquelin , Alexandre Torgue , Fabrice Gasnier CC: , , , , , Subject: [PATCH v3 4/8] dt-bindings: iio: dfsdm: move to backend framework Date: Wed, 3 Jul 2024 18:05:29 +0200 Message-ID: <20240703160535.2277871-5-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240703160535.2277871-1-olivier.moysan@foss.st.com> References: <20240703160535.2277871-1-olivier.moysan@foss.st.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: SHFCAS1NODE2.st.com (10.75.129.73) 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=2024-07-03_11,2024-07-03_01,2024-05-17_01 Change the DFSDM binding to use the new IIO backend framework, along with the adoption of IIO generic channels. This binding change allows to add scaling support to the DFSDM. Keep the legacy binding as deprecated for backward compatibility. The io-backends property is supported only in generic IIO channel binding. - Channel description with the generic binding (Audio and Analog): Properties superseded by generic properties: st,adc-channels: becomes "reg" property in channel node st,adc-channel-names: becomes "label" property in channel node Properties moved to channel child node: st,adc-channel-types: becomes st,adc-channel-type st,adc-channel-clk-src, st,adc-alt-channel - Analog binding: DFSDM filter channel is configured as an IIO backend consumer. Add io-backends property in channel child nodes. DFSDM is no more configured as a channel consumer from SD modulator. Use of io-channels in DFSDM node is deprecated. - Audio binding: DFSDM audio DAI is configured as a channel consumer from DFSDM filter. No change compare to legacy. Signed-off-by: Olivier Moysan --- .../bindings/iio/adc/st,stm32-dfsdm-adc.yaml | 153 +++++++++++++++++- 1 file changed, 147 insertions(+), 6 deletions(-) diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml index 2722edab1d9a..5a5bc8b96402 100644 --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml @@ -102,9 +102,11 @@ patternProperties: items: minimum: 0 maximum: 7 + deprecated: true st,adc-channel-names: description: List of single-ended channel names. + deprecated: true st,filter-order: description: | @@ -118,6 +120,12 @@ patternProperties: "#io-channel-cells": const: 1 + '#address-cells': + const: 1 + + '#size-cells': + const: 0 + st,adc-channel-types: description: | Single-ended channel input type. @@ -128,6 +136,7 @@ patternProperties: items: enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ] $ref: /schemas/types.yaml#/definitions/non-unique-string-array + deprecated: true st,adc-channel-clk-src: description: | @@ -139,6 +148,7 @@ patternProperties: items: enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ] $ref: /schemas/types.yaml#/definitions/non-unique-string-array + deprecated: true st,adc-alt-channel: description: @@ -147,6 +157,7 @@ patternProperties: If not set, channel n is connected to SPI input n. If set, channel n is connected to SPI input n + 1. type: boolean + deprecated: true st,filter0-sync: description: @@ -165,11 +176,60 @@ patternProperties: - compatible - reg - interrupts - - st,adc-channels - - st,adc-channel-names - st,filter-order - "#io-channel-cells" + patternProperties: + "^channel@([0-7])$": + type: object + $ref: adc.yaml + unevaluatedProperties: false + description: Represents the external channels which are connected to the DFSDM. + + properties: + reg: + maxItems: 1 + + label: + description: + Unique name to identify which channel this is. + + st,adc-channel-type: + description: | + Single-ended channel input type. + - "SPI_R": SPI with data on rising edge (default) + - "SPI_F": SPI with data on falling edge + - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1 + - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0 + $ref: /schemas/types.yaml#/definitions/string + enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ] + + st,adc-channel-clk-src: + description: | + Conversion clock source. + - "CLKIN": external SPI clock (CLKIN x) + - "CLKOUT": internal SPI clock (CLKOUT) (default) + - "CLKOUT_F": internal SPI clock divided by 2 (falling edge). + - "CLKOUT_R": internal SPI clock divided by 2 (rising edge). + $ref: /schemas/types.yaml#/definitions/string + enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ] + + st,adc-alt-channel: + description: + Must be defined if two sigma delta modulators are + connected on same SPI input. + If not set, channel n is connected to SPI input n. + If set, channel n is connected to SPI input n + 1. + type: boolean + + io-backends: + description: + Used to pipe external sigma delta modulator or internal ADC backend to DFSDM channel. + maxItems: 1 + + required: + - reg + allOf: - if: properties: @@ -199,9 +259,19 @@ patternProperties: description: From common IIO binding. Used to pipe external sigma delta modulator or internal ADC output to DFSDM channel. + deprecated: true - required: - - io-channels + if: + required: + - st,adc-channels + then: + required: + - io-channels + + patternProperties: + "^channel@([0-9])$": + required: + - io-backends - if: properties: @@ -298,7 +368,77 @@ examples: #address-cells = <1>; #size-cells = <0>; + // Example 1: Audio use case with generic binding dfsdm0: filter@0 { + compatible = "st,stm32-dfsdm-dmic"; + reg = <0>; + interrupts = ; + dmas = <&dmamux1 101 0x400 0x01>; + dma-names = "rx"; + #io-channel-cells = <1>; + #address-cells = <1>; + #size-cells = <0>; + st,filter-order = <5>; + + channel@1 { + reg = <1>; + label = "dmic0"; + st,adc-channel-type = "SPI_R"; + st,adc-channel-clk-src = "CLKOUT"; + st,adc-alt-channel; + }; + + asoc_pdm0: dfsdm-dai { + compatible = "st,stm32h7-dfsdm-dai"; + #sound-dai-cells = <0>; + io-channels = <&dfsdm0 0>; + }; + }; + + // Example 1: Analog use case with generic binding + dfsdm1: filter@1 { + compatible = "st,stm32-dfsdm-adc"; + reg = <1>; + interrupts = ; + dmas = <&dmamux1 102 0x400 0x01>; + dma-names = "rx"; + st,filter-order = <1>; + #io-channel-cells = <1>; + #address-cells = <1>; + #size-cells = <0>; + + channel@2 { + reg = <2>; + label = "in2"; + st,adc-channel-type = "SPI_F"; + st,adc-channel-clk-src = "CLKOUT"; + st,adc-alt-channel; + io-backends = <&sd_adc2>; + }; + + channel@3 { + reg = <3>; + label = "in3"; + st,adc-channel-type = "SPI_R"; + st,adc-channel-clk-src = "CLKOUT"; + io-backends = <&sd_adc3>; + }; + }; + }; + + - | + #include + #include + dfsdm_2: dfsdm@4400d000 { + compatible = "st,stm32mp1-dfsdm"; + reg = <0x4400d000 0x800>; + clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>; + clock-names = "dfsdm", "audio"; + #address-cells = <1>; + #size-cells = <0>; + + // Example 3: Audio use case with legacy binding + dfsdm0_2: filter@0 { compatible = "st,stm32-dfsdm-dmic"; reg = <0>; interrupts = ; @@ -311,14 +451,15 @@ examples: st,adc-channel-clk-src = "CLKOUT"; st,filter-order = <5>; - asoc_pdm0: dfsdm-dai { + asoc_pdm0_2: dfsdm-dai { compatible = "st,stm32h7-dfsdm-dai"; #sound-dai-cells = <0>; io-channels = <&dfsdm0 0>; }; }; - dfsdm_pdm1: filter@1 { + // Example 3: Analog use case with legacy binding + dfsdm1_2: filter@1 { compatible = "st,stm32-dfsdm-adc"; reg = <1>; interrupts = ; From patchwork Wed Jul 3 16:05:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 1956345 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=foss.st.com header.i=@foss.st.com header.a=rsa-sha256 header.s=selector1 header.b=WuZEpSdb; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=2604:1380:45e3:2400::1; helo=sv.mirrors.kernel.org; envelope-from=devicetree+bounces-82922-incoming-dt=patchwork.ozlabs.org@vger.kernel.org; receiver=patchwork.ozlabs.org) Received: from sv.mirrors.kernel.org (sv.mirrors.kernel.org [IPv6:2604:1380:45e3:2400::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WDl8F42Zfz1xqm for ; Thu, 4 Jul 2024 02:09:01 +1000 (AEST) Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id C9E0328925C for ; Wed, 3 Jul 2024 16:08:59 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A35DB1836CC; Wed, 3 Jul 2024 16:08:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="WuZEpSdb" X-Original-To: devicetree@vger.kernel.org Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) (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 C6B62181CF6; Wed, 3 Jul 2024 16:08:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.132.182.106 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720022906; cv=none; b=KEGPhuq1In/TUkXdVVVdIGl0RnJzsi4F99z1A+Y4VGYGxYlaQDBMizZXXiY+FryFjLObAcd+Q1UuUnp6D7/Si/94iuNn2xjW5UJlyhHxNKrcHd8psJsIY7s9yytBu/Pl/qnC79W7/EDN2OElrpiStVS3ZtoCIZztrDsSDfxVZvA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720022906; c=relaxed/simple; bh=7BaNISH55n/A/MVA9c++n/zTtTouz5E5BL82HUun+bU=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mb/Z6a123ES30A6oTsstbCRVPRZtvp/JEya6HKuX6l+9c/KCGaRKQpcYX5m363vvRkpvbD2o6FvvVKpjMsMckEbKzqFdq1dUBdfPzkO5dFQ9KOpIi5MfSBLD4PkX7KuXQITOb0mGcpEBQLzgTRwjmxLJ+0dQi1TvJBvLzFFof9M= 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=WuZEpSdb; arc=none smtp.client-ip=185.132.182.106 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 Received: from pps.filterd (m0241204.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 463FtSDj024015; Wed, 3 Jul 2024 18:08:10 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= P+kNXBwzIwoxxa4OyxqdIx5+Zo644vt/ZB+ntrLN0Ns=; b=WuZEpSdbcUXBU1Ff HPXQfgAl3nQSUnwv55nc8rHvADFKNtYeApr+aOCwXlu01xEROOu+a5V6l/pX01Ej /Y2hyTe/dUxKv3haIzTHfoCwHAG2jQxLQ+ODads6n+/qK14dxBJtossQ2n+wLjH3 q2KTi8cLHW9mDNt3ERzIohzpNUSxpXHuu1gtCVd4H+MJUIhDWSZ0AFy2NVx2aoee adIePkC0yny6Xjik+ne2359vk4plTvnCwqgN+DfOImUyBKvV+dWhTmJ5U/vQB5Ne Z7yG5rU2z1wiVAnNBDYmCNmSfQki3b2WX/P5rC4DHLfIqpwwp403FPAFVrmCt02I /b+Gtw== 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 4029kx1ggf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 03 Jul 2024 18:08:10 +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 0095D40046; Wed, 3 Jul 2024 18:08:04 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id A28E02291B2; Wed, 3 Jul 2024 18:07:31 +0200 (CEST) Received: from localhost (10.252.27.110) 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; Wed, 3 Jul 2024 18:07:31 +0200 From: Olivier Moysan To: Jonathan Cameron , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Arnaud Pouliquen CC: Olivier Moysan , , , Subject: [PATCH v3 5/8] dt-bindings: iio: add backend support to sd modulator Date: Wed, 3 Jul 2024 18:05:30 +0200 Message-ID: <20240703160535.2277871-6-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240703160535.2277871-1-olivier.moysan@foss.st.com> References: <20240703160535.2277871-1-olivier.moysan@foss.st.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: SHFCAS1NODE2.st.com (10.75.129.73) 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=2024-07-03_11,2024-07-03_01,2024-05-17_01 The legacy sd modulator driver registers the sigma delta modulator as an IIO channel provider. This implementation is not convenient when the SD modulator has to be cascaded with another IIO device. The scaling information is distributed across devices, which makes it difficult to report consistent scaling data on IIO devices. The solution is to expose these cascaded IIO devices as an aggregate device, which report global scaling information. Add IIO backend support to SD modulator to allow scaling information management. Signed-off-by: Olivier Moysan --- .../iio/adc/sigma-delta-modulator.yaml | 24 +++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.yaml b/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.yaml index cab0d425eaa4..e34aa560da63 100644 --- a/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.yaml +++ b/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.yaml @@ -18,18 +18,38 @@ properties: - sd-modulator - ads1201 + '#io-backend-cells': + const: 0 + '#io-channel-cells': const: 0 + reg: + maxItems: 1 + + vref-supply: + description: Phandle to the vref input analog reference voltage. + required: - compatible - - '#io-channel-cells' + +allOf: + - anyOf: + - required: ['#io-backend-cells'] + - required: ['#io-channel-cells'] additionalProperties: false examples: - | - ads1202: adc { + // Exemple1: SD modulator is an IIO backend device + ads1201_0 { + compatible = "ti,ads1201"; + #io-backend-cells = <0>; + }; + + //Example2: SD modulator is an IIO channel provider + ads1201_1 { compatible = "sd-modulator"; #io-channel-cells = <0>; };