From patchwork Wed Jul 24 15:36:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 13741119 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9D1EEC3DA63 for ; Wed, 24 Jul 2024 15:40:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=opIVBJcqT90KCt+B1wmwMEzKfiskRGNNy4kpQrfUzOM=; b=gfaTSTJw638HsTp7+sR4vtjKHt xQyPC1+Kvd+REY/4NGvnIEXUY4G3R49XPH23PBAHkWHK4FimpLZ83BpmYWM+OnbO4+4ybogKP+7BY wi6o8rNljCoNsn09ww3l5RSrwfdvFe4vqtGAbADkjC/bx+i+9r3Y3b9Zm4ypwm3QHrWYK6gVsFNAa ax5ffV0pko8ZOL3vbyyUhdnoNGOHskKwdZV8VwakxiQUEcdEAqCegZyoOOGIH661+rqS7NviUhAws EFU+vFZL/7b0ZVQYdRcNjqXyBvvUnybjAtUyXClIC7MtqFIltT9wBaKHnqS4PqYVK+evWcO2DLPXp oPaEb3Ag==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sWe5u-0000000FngM-2Z0x; Wed, 24 Jul 2024 15:39:58 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sWe5T-0000000FnXQ-3jo2 for linux-arm-kernel@lists.infradead.org; Wed, 24 Jul 2024 15:39:33 +0000 Received: from pps.filterd (m0369457.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 46OBRJaZ025712; Wed, 24 Jul 2024 17:39:23 +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= opIVBJcqT90KCt+B1wmwMEzKfiskRGNNy4kpQrfUzOM=; b=6qNFYsx0vDn0VSRp tu9vmY5UU3X8CM58NYGKezZCO5QGB3rsem6qjpZpK/tywbDf99v6w9OAjwVxd3FC 2XEaYVTMRT6sDlB4oOkoAwFi7xh20Lej9szyki3Yiykvaa1nysK5c9VSReSX6Eed XjjukYkNmgznUPLRV29gM5UcZT7NbwQqeojp18RCKawWKqNFKLRyw958pmk1cJXv 2clXkJymfdhQgUbQ0GeYUKmyufB/WM65qguCbGI8j9GShsmxjFt9rkxkk/BlWRAl eOhu2jhSqMmrZMMGWPL7TKT6lldP0xsg4Y2Ntjd+3IQvb7Xfz1Nuajm1RMcKmj14 qojnKQ== 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 40gr6j5x2w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 Jul 2024 17:39:23 +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 569F540045; Wed, 24 Jul 2024 17:39:19 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id E4FF22414BA; Wed, 24 Jul 2024 17:38:31 +0200 (CEST) Received: from localhost (10.252.12.39) 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 15.1.2507.37; Wed, 24 Jul 2024 17:38:31 +0200 From: Olivier Moysan To: , Olivier Moysan , Arnaud Pouliquen , Jonathan Cameron , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Maxime Coquelin , Alexandre Torgue CC: , , , , , Subject: [PATCH v5 4/9] dt-bindings: iio: dfsdm: move to backend framework Date: Wed, 24 Jul 2024 17:36:32 +0200 Message-ID: <20240724153639.803263-5-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240724153639.803263-1-olivier.moysan@foss.st.com> References: <20240724153639.803263-1-olivier.moysan@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.252.12.39] 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=2024-07-24_15,2024-07-24_01,2024-05-17_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240724_083932_259787_2FEE4FDD X-CRM114-Status: GOOD ( 15.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 Reviewed-by: Rob Herring (Arm) --- .../bindings/iio/adc/st,stm32-dfsdm-adc.yaml | 124 +++++++++++++++--- 1 file changed, 108 insertions(+), 16 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..ceadd73504a4 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: + maximum: 7 + + 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). + $ref: /schemas/types.yaml#/definitions/string + enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ] + + st,adc-alt-channel: + description: + Must be defined if two sigma delta modulators are + connected on same SPI input. + If not set, channel n is connected to SPI input n. + If set, channel n is connected to SPI input n + 1. + type: boolean + + io-backends: + description: + Used to pipe external sigma delta modulator or internal ADC backend to DFSDM channel. + maxItems: 1 + + required: + - reg + allOf: - if: properties: @@ -199,9 +259,19 @@ patternProperties: description: From common IIO binding. Used to pipe external sigma delta modulator or internal ADC output to DFSDM channel. + deprecated: true - required: - - io-channels + if: + required: + - st,adc-channels + then: + required: + - io-channels + + patternProperties: + "^channel@([0-7])$": + required: + - io-backends - if: properties: @@ -298,6 +368,7 @@ 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>; @@ -305,12 +376,18 @@ examples: dmas = <&dmamux1 101 0x400 0x01>; dma-names = "rx"; #io-channel-cells = <1>; - st,adc-channels = <1>; - st,adc-channel-names = "dmic0"; - st,adc-channel-types = "SPI_R"; - st,adc-channel-clk-src = "CLKOUT"; + #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>; @@ -318,20 +395,35 @@ examples: }; }; - dfsdm_pdm1: filter@1 { + // Example 2: 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"; - #io-channel-cells = <1>; - st,adc-channels = <2 3>; - st,adc-channel-names = "in2", "in3"; - st,adc-channel-types = "SPI_R", "SPI_R"; - st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F"; - io-channels = <&sd_adc2 &sd_adc3>; 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>; + }; }; }; -... +... \ No newline at end of file From patchwork Wed Jul 24 15:36:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 13741120 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 501C8C3DA63 for ; 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Wed, 24 Jul 2024 17:40:08 +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 A85BC40048; Wed, 24 Jul 2024 17:40:04 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 43264241B43; Wed, 24 Jul 2024 17:39:35 +0200 (CEST) Received: from localhost (10.252.12.39) 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 15.1.2507.37; Wed, 24 Jul 2024 17:39:34 +0200 From: Olivier Moysan To: , Jonathan Cameron , Lars-Peter Clausen , Maxime Coquelin , Alexandre Torgue CC: Olivier Moysan , , , , Subject: [PATCH v5 7/9] iio: adc: stm32-dfsdm: adopt generic channels bindings Date: Wed, 24 Jul 2024 17:36:35 +0200 Message-ID: <20240724153639.803263-8-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240724153639.803263-1-olivier.moysan@foss.st.com> References: <20240724153639.803263-1-olivier.moysan@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.252.12.39] 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=2024-07-24_15,2024-07-24_01,2024-05-17_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240724_084017_281906_8481B919 X-CRM114-Status: GOOD ( 20.32 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Move to generic channels binding to ease new backend framework adoption and prepare the convergence with MDF IP support on STM32MP2 SoC family. Legacy binding: DFSDM is an IIO channel consumer. SD modulator is an IIO channels provider. The channel phandles are provided in DT through io-channels property and channel indexes through st,adc-channels property. New binding: DFSDM is an IIO channel provider. The channel indexes are given by reg property in channel child node. This new binding is intended to be used with SD modulator IIO backends. It does not support SD modulator legacy IIO devices. The st,adc-channels property presence is used to discriminate between legacy and backend bindings. The support of the DFSDM legacy channels and SD modulator IIO devices is kept for backward compatibility. Signed-off-by: Olivier Moysan --- drivers/iio/adc/stm32-dfsdm-adc.c | 190 ++++++++++++++++++++++++------ 1 file changed, 154 insertions(+), 36 deletions(-) diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index fabd654245f5..da7dd804c84d 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -666,6 +666,64 @@ static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, return 0; } +static int stm32_dfsdm_generic_channel_parse_of(struct stm32_dfsdm *dfsdm, + struct iio_dev *indio_dev, + struct iio_chan_spec *ch, + struct fwnode_handle *node) +{ + struct stm32_dfsdm_channel *df_ch; + const char *of_str; + int ret, val; + + ret = fwnode_property_read_u32(node, "reg", &ch->channel); + if (ret < 0) { + dev_err(&indio_dev->dev, "Missing channel index %d\n", ret); + return ret; + } + + if (ch->channel >= dfsdm->num_chs) { + dev_err(&indio_dev->dev, " Error bad channel number %d (max = %d)\n", + ch->channel, dfsdm->num_chs); + return -EINVAL; + } + + ret = fwnode_property_read_string(node, "label", &ch->datasheet_name); + if (ret < 0) { + dev_err(&indio_dev->dev, + " Error parsing 'label' for idx %d\n", ch->channel); + return ret; + } + + df_ch = &dfsdm->ch_list[ch->channel]; + df_ch->id = ch->channel; + + ret = fwnode_property_read_string(node, "st,adc-channel-type", &of_str); + if (!ret) { + val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); + if (val < 0) + return val; + } else { + val = 0; + } + df_ch->type = val; + + ret = fwnode_property_read_string(node, "st,adc-channel-clk-src", &of_str); + if (!ret) { + val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); + if (val < 0) + return val; + } else { + val = 0; + } + df_ch->src = val; + + ret = fwnode_property_read_u32(node, "st,adc-alt-channel", &df_ch->alt_si); + if (ret != -EINVAL) + df_ch->alt_si = 0; + + return 0; +} + static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, @@ -1227,7 +1285,8 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; - ret = iio_hw_consumer_enable(adc->hwc); + if (adc->hwc) + ret = iio_hw_consumer_enable(adc->hwc); if (ret < 0) { dev_err(&indio_dev->dev, "%s: IIO enable failed (channel %d)\n", @@ -1236,7 +1295,8 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, return ret; } ret = stm32_dfsdm_single_conv(indio_dev, chan, val); - iio_hw_consumer_disable(adc->hwc); + if (adc->hwc) + iio_hw_consumer_disable(adc->hwc); if (ret < 0) { dev_err(&indio_dev->dev, "%s: Conversion failed (channel %d)\n", @@ -1362,15 +1422,18 @@ static int stm32_dfsdm_dma_request(struct device *dev, return 0; } -static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, - struct iio_chan_spec *ch) +static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, struct iio_chan_spec *ch, + struct fwnode_handle *child) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int ret; - ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); + if (child) + ret = stm32_dfsdm_generic_channel_parse_of(adc->dfsdm, indio_dev, ch, child); + else /* Legacy binding */ + ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); if (ret < 0) - return ret; + return dev_err_probe(&indio_dev->dev, ret, "Failed to parse channel\n"); ch->type = IIO_VOLTAGE; ch->indexed = 1; @@ -1385,6 +1448,7 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, if (adc->dev_data->type == DFSDM_AUDIO) { ch->ext_info = dfsdm_adc_audio_ext_info; + ch->scan_index = 0; } else { ch->scan_type.shift = 8; } @@ -1396,20 +1460,67 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, &adc->dfsdm->ch_list[ch->channel]); } +static int stm32_dfsdm_chan_init(struct iio_dev *indio_dev, struct iio_chan_spec *channels) +{ + int num_ch = indio_dev->num_channels; + int chan_idx = 0; + int ret; + + for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { + channels[chan_idx].scan_index = chan_idx; + ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &channels[chan_idx], NULL); + if (ret < 0) + return dev_err_probe(&indio_dev->dev, ret, "Channels init failed\n"); + } + + return 0; +} + +static int stm32_dfsdm_generic_chan_init(struct iio_dev *indio_dev, struct iio_chan_spec *channels) +{ + int chan_idx = 0, ret; + + device_for_each_child_node_scoped(&indio_dev->dev, child) { + /* Skip DAI node in DFSDM audio nodes */ + if (fwnode_property_present(child, "compatible")) + continue; + + channels[chan_idx].scan_index = chan_idx; + ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &channels[chan_idx], child); + if (ret < 0) + return dev_err_probe(&indio_dev->dev, ret, "Channels init failed\n"); + + chan_idx++; + } + + return chan_idx; +} + static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) { struct iio_chan_spec *ch; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_channel *d_ch; - int ret; + bool legacy = false; + int num_ch, ret; + + /* If st,adc-channels is defined legacy binding is used. Else assume generic binding. */ + num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, "st,adc-channels"); + if (num_ch == 1) + legacy = true; ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); if (!ch) return -ENOMEM; - ch->scan_index = 0; + indio_dev->num_channels = 1; + indio_dev->channels = ch; + + if (legacy) + ret = stm32_dfsdm_chan_init(indio_dev, ch); + else + ret = stm32_dfsdm_generic_chan_init(indio_dev, ch); - ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch); if (ret < 0) { dev_err(&indio_dev->dev, "Channels init failed\n"); return ret; @@ -1420,9 +1531,6 @@ static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) adc->spi_freq = adc->dfsdm->spi_master_freq; - indio_dev->num_channels = 1; - indio_dev->channels = ch; - return stm32_dfsdm_dma_request(dev, indio_dev); } @@ -1430,43 +1538,53 @@ static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) { struct iio_chan_spec *ch; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); - int num_ch; - int ret, chan_idx; + int num_ch, ret; + bool legacy = false; adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); if (ret < 0) return ret; - num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, - "st,adc-channels"); - if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) { - dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); - return num_ch < 0 ? num_ch : -EINVAL; - } + num_ch = device_get_child_node_count(&indio_dev->dev); + if (!num_ch) { + /* No channels nodes found. Assume legacy binding */ + num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, "st,adc-channels"); + if (num_ch < 0) { + dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); + return num_ch; + } - /* Bind to SD modulator IIO device */ - adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); - if (IS_ERR(adc->hwc)) - return -EPROBE_DEFER; + legacy = true; + } - ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), - GFP_KERNEL); - if (!ch) - return -ENOMEM; + if (num_ch > adc->dfsdm->num_chs) { + dev_err(&indio_dev->dev, "Number of channel [%d] exceeds [%d]\n", + num_ch, adc->dfsdm->num_chs); + return -EINVAL; + } + indio_dev->num_channels = num_ch; - for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { - ch[chan_idx].scan_index = chan_idx; - ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]); - if (ret < 0) { - dev_err(&indio_dev->dev, "Channels init failed\n"); - return ret; - } + if (legacy) { + /* Bind to SD modulator IIO device. */ + adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); + if (IS_ERR(adc->hwc)) + return dev_err_probe(&indio_dev->dev, -EPROBE_DEFER, + "waiting for SD modulator\n"); } - indio_dev->num_channels = num_ch; + ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), GFP_KERNEL); + if (!ch) + return -ENOMEM; indio_dev->channels = ch; + if (legacy) + ret = stm32_dfsdm_chan_init(indio_dev, ch); + else + ret = stm32_dfsdm_generic_chan_init(indio_dev, ch); + if (ret < 0) + return ret; + init_completion(&adc->completion); /* Optionally request DMA */ From patchwork Wed Jul 24 15:36:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 13741121 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 EEC56C3DA63 for ; 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Wed, 24 Jul 2024 17:41:22 +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 5C15740045; Wed, 24 Jul 2024 17:41:12 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id AAF6D241B45; Wed, 24 Jul 2024 17:40:37 +0200 (CEST) Received: from localhost (10.252.12.39) 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 15.1.2507.37; Wed, 24 Jul 2024 17:40:37 +0200 From: Olivier Moysan To: , Jonathan Cameron , Lars-Peter Clausen , Maxime Coquelin , Alexandre Torgue CC: Olivier Moysan , Nuno Sa , , , , Subject: [PATCH v5 9/9] iio: adc: stm32-dfsdm: add scaling support to dfsdm Date: Wed, 24 Jul 2024 17:36:37 +0200 Message-ID: <20240724153639.803263-10-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240724153639.803263-1-olivier.moysan@foss.st.com> References: <20240724153639.803263-1-olivier.moysan@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.252.12.39] 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=2024-07-24_15,2024-07-24_01,2024-05-17_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240724_084131_717088_196C29D2 X-CRM114-Status: GOOD ( 23.99 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add scaling support to STM32 DFSDM. When used in an analog context, a DFSDM filter typically converts the data from a sigma delta modulator. The IIO device associated to the DFSDM filter provides these data as raw data. The IIO device can provide scaling information (voltage and offset) to allow conversion of raw data into physical values. With the new binding based on IIO backend framework, the sigma delta modulators are defined as backends providing scaling information. The scaling is not supported with legacy binding. Signed-off-by: Olivier Moysan Acked-by: Nuno Sa --- drivers/iio/adc/Kconfig | 1 + drivers/iio/adc/stm32-dfsdm-adc.c | 105 +++++++++++++++++++++++++++++- 2 files changed, 105 insertions(+), 1 deletion(-) diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 836747138ed7..dcf6a14e2ea2 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -1237,6 +1237,7 @@ config STM32_DFSDM_ADC select IIO_BUFFER select IIO_BUFFER_HW_CONSUMER select IIO_TRIGGERED_BUFFER + select IIO_BACKEND help Select this option to support ADCSigma delta modulator for STMicroelectronics STM32 digital filter for sigma delta converter. diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index da7dd804c84d..2c9270a87dc9 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -78,6 +79,7 @@ struct stm32_dfsdm_adc { /* ADC specific */ unsigned int oversamp; struct iio_hw_consumer *hwc; + struct iio_backend **backend; struct completion completion; u32 *buffer; @@ -672,6 +674,8 @@ static int stm32_dfsdm_generic_channel_parse_of(struct stm32_dfsdm *dfsdm, struct fwnode_handle *node) { struct stm32_dfsdm_channel *df_ch; + struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + struct iio_backend *backend; const char *of_str; int ret, val; @@ -721,6 +725,14 @@ static int stm32_dfsdm_generic_channel_parse_of(struct stm32_dfsdm *dfsdm, if (ret != -EINVAL) df_ch->alt_si = 0; + if (adc->dev_data->type == DFSDM_IIO) { + backend = devm_iio_backend_fwnode_get(&indio_dev->dev, NULL, node); + if (IS_ERR(backend)) + return dev_err_probe(&indio_dev->dev, PTR_ERR(backend), + "Failed to get backend\n"); + adc->backend[ch->scan_index] = backend; + } + return 0; } @@ -1056,6 +1068,7 @@ static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev, static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + int i = 0; int ret; /* Reset adc buffer index */ @@ -1067,6 +1080,15 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) return ret; } + if (adc->backend) { + while (adc->backend[i]) { + ret = iio_backend_enable(adc->backend[i]); + if (ret < 0) + return ret; + i++; + } + } + ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); if (ret < 0) goto err_stop_hwc; @@ -1099,6 +1121,7 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + int i = 0; stm32_dfsdm_stop_conv(indio_dev); @@ -1106,6 +1129,13 @@ static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) stm32_dfsdm_stop_dfsdm(adc->dfsdm); + if (adc->backend) { + while (adc->backend[i]) { + iio_backend_disable(adc->backend[i]); + i++; + } + } + if (adc->hwc) iio_hw_consumer_disable(adc->hwc); @@ -1278,8 +1308,16 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, int *val2, long mask) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + + struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; + struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; + u32 max = flo->max << (flo->lshift - chan->scan_type.shift); + int idx = chan->scan_index; int ret; + if (flo->lshift < chan->scan_type.shift) + max = flo->max >> (chan->scan_type.shift - flo->lshift); + switch (mask) { case IIO_CHAN_INFO_RAW: ret = iio_device_claim_direct_mode(indio_dev); @@ -1287,6 +1325,8 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, return ret; if (adc->hwc) ret = iio_hw_consumer_enable(adc->hwc); + if (adc->backend) + ret = iio_backend_enable(adc->backend[idx]); if (ret < 0) { dev_err(&indio_dev->dev, "%s: IIO enable failed (channel %d)\n", @@ -1297,6 +1337,8 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, ret = stm32_dfsdm_single_conv(indio_dev, chan, val); if (adc->hwc) iio_hw_consumer_disable(adc->hwc); + if (adc->backend) + iio_backend_disable(adc->backend[idx]); if (ret < 0) { dev_err(&indio_dev->dev, "%s: Conversion failed (channel %d)\n", @@ -1316,6 +1358,50 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, *val = adc->sample_freq; return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + /* + * Scale is expressed in mV. + * When fast mode is disabled, actual resolution may be lower + * than 2^n, where n = realbits - 1. + * This leads to underestimating the input voltage. + * To compensate this deviation, the voltage reference can be + * corrected with a factor = realbits resolution / actual max + */ + if (adc->backend) { + ret = iio_backend_read_scale(adc->backend[idx], chan, val, NULL); + if (ret < 0) + return ret; + + *val = div_u64((u64)*val * (u64)BIT(DFSDM_DATA_RES - 1), max); + *val2 = chan->scan_type.realbits; + if (chan->differential) + *val *= 2; + } + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_OFFSET: + /* + * DFSDM output data are in the range [-2^n, 2^n], + * with n = realbits - 1. + * - Differential modulator: + * Offset correspond to SD modulator offset. + * - Single ended modulator: + * Input is in [0V, Vref] range, + * where 0V corresponds to -2^n, and Vref to 2^n. + * Add 2^n to offset. (i.e. middle of input range) + * offset = offset(sd) * vref / res(sd) * max / vref. + */ + if (adc->backend) { + ret = iio_backend_read_offset(adc->backend[idx], chan, val, NULL); + if (ret < 0) + return ret; + + *val = div_u64((u64)max * *val, BIT(*val2 - 1)); + if (!chan->differential) + *val += max; + } + return IIO_VAL_INT; } return -EINVAL; @@ -1442,7 +1528,15 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, struct iio_c * IIO_CHAN_INFO_RAW: used to compute regular conversion * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling */ - ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + if (child) { + ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET); + } else { + /* Legacy. Scaling not supported */ + ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + } + ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | BIT(IIO_CHAN_INFO_SAMP_FREQ); @@ -1571,6 +1665,14 @@ static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) if (IS_ERR(adc->hwc)) return dev_err_probe(&indio_dev->dev, -EPROBE_DEFER, "waiting for SD modulator\n"); + } else { + /* Generic binding. SD modulator IIO device not used. Use SD modulator backend. */ + adc->hwc = NULL; + + adc->backend = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*adc->backend), + GFP_KERNEL); + if (!adc->backend) + return -ENOMEM; } ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), GFP_KERNEL); @@ -1795,3 +1897,4 @@ module_platform_driver(stm32_dfsdm_adc_driver); MODULE_DESCRIPTION("STM32 sigma delta ADC"); MODULE_AUTHOR("Arnaud Pouliquen "); MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS(IIO_BACKEND);