From patchwork Thu Jul 15 03:12:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liam Beguin X-Patchwork-Id: 12378363 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01046C47E48 for ; Thu, 15 Jul 2021 03:12:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFF5661396 for ; Thu, 15 Jul 2021 03:12:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233343AbhGODPj (ORCPT ); Wed, 14 Jul 2021 23:15:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233416AbhGODPi (ORCPT ); Wed, 14 Jul 2021 23:15:38 -0400 Received: from mail-qt1-x830.google.com (mail-qt1-x830.google.com [IPv6:2607:f8b0:4864:20::830]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D4C6C061767; Wed, 14 Jul 2021 20:12:45 -0700 (PDT) Received: by mail-qt1-x830.google.com with SMTP id x24so3510293qts.11; Wed, 14 Jul 2021 20:12:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=iG9doMSkOjGbuRC6SLDooD1hmJaLMt+b8S+uRbwt3Gs=; b=pLISMormbjm2qrxlnj+b6/aOoaQsHPIRQ94TSugwqMuhT11+1SJXlbnPzv7WC/vAQA K90IBO6+hBJuy2TVxq16p9lYBpyVX7lEQrTiwYOuLpa0Vmh3TrBA6KSDnwADq+cPtSFv SIPjpiuOG13TgDAi/9CXV/sL0DC+V+FH+dVx6cfpsjK1cLxOYp/PXaMsuVoeeNlTAo4K /LMKRfc7auXtDoXyV3RGBxkW99eLBhyL/C7cWn4oLonU4ON3rENly7Vyp/DZnTJYi3p3 qBWmf//pSTETXekyln8t0ArqREmkV7T1wB2bcG6DF+gGDod+yGeDxdO+5xF9OaULL8m3 82kg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=iG9doMSkOjGbuRC6SLDooD1hmJaLMt+b8S+uRbwt3Gs=; b=JdfkhNbsqD2fjWDUx0aUN6+HBEvAU94L3aSB3OPWimrNH8UhZBritH4Cc3qAAi+Wzp zYw0Zb2Wgq4UH1co7KQR4gv7rlF2gWez4Ub1VIHFCOgyjlIyixjYsV1681uPAvIKOn5P sDIfGqlJvMakj7rR69ekSJkUUV4+6iO0p5yo0zuVcOZ2CjxQ3WMuOjfC6k1N/R+/1tKD g5qbq78YULIrM1sIgaqxVDKEgJJ/aidfozbjnrN2CNzwk8YApJOq+YtmGgF1aVKSNQcL SKwGdD6quy39gZnXbxIpSWuZMf8SDxfWVo0wrequ7/KyDhsU+9/PR8PKZrf+xW7qiYrE 4IyQ== X-Gm-Message-State: AOAM532t1RrmhR8iQ0UK+JkDP4qx2kEndTJhnLHOAnUKnPu24m4W7j4y 7w2euEbXrssAeT/xPpxv1xg= X-Google-Smtp-Source: ABdhPJwon8CRGlIixWaw59adLEzkn7nOwC2lXLvSvQ3CsmICZFdFnnQyfEn+W0j9K3sZX839jzfQyA== X-Received: by 2002:ac8:dc9:: with SMTP id t9mr1572776qti.293.1626318764633; Wed, 14 Jul 2021 20:12:44 -0700 (PDT) Received: from shaak.. (198-48-202-89.cpe.pppoe.ca. [198.48.202.89]) by smtp.gmail.com with ESMTPSA id t125sm1932847qkf.41.2021.07.14.20.12.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Jul 2021 20:12:44 -0700 (PDT) From: Liam Beguin To: liambeguin@gmail.com, peda@axentia.se, jic23@kernel.org, lars@metafoo.de, pmeerw@pmeerw.net Cc: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, robh+dt@kernel.org Subject: [PATCH v5 08/10] iio: afe: rescale: add temperature transducers Date: Wed, 14 Jul 2021 23:12:13 -0400 Message-Id: <20210715031215.1534938-9-liambeguin@gmail.com> X-Mailer: git-send-email 2.30.1.489.g328c10930387 In-Reply-To: <20210715031215.1534938-1-liambeguin@gmail.com> References: <20210715031215.1534938-1-liambeguin@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Liam Beguin A temperature transducer is a device that converts a thermal quantity into any other physical quantity. This patch add support for temperature to voltage (like the LTC2997) and temperature to current (like the AD590) linear transducers. In both cases these are assumed to be connected to a voltage ADC. Signed-off-by: Liam Beguin --- drivers/iio/afe/iio-rescale.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c index 055f6b7c9869..4b3b5e9bbe40 100644 --- a/drivers/iio/afe/iio-rescale.c +++ b/drivers/iio/afe/iio-rescale.c @@ -397,11 +397,38 @@ static int rescale_temp_sense_rtd_props(struct device *dev, return 0; } +static int rescale_temp_transducer_props(struct device *dev, + struct rescale *rescale) +{ + s32 offset = 0; + s32 sense = 1; + s32 alpha; + s64 tmp; + int ret; + + device_property_read_u32(dev, "sense-offset-millicelsius", &offset); + device_property_read_u32(dev, "sense-resistor-ohms", &sense); + ret = device_property_read_u32(dev, "alpha-ppm-per-celsius", &alpha); + if (ret) { + dev_err(dev, "failed to read alpha-ppm-per-celsius: %d\n", ret); + return ret; + } + + rescale->numerator = 1000000; + rescale->denominator = alpha * sense; + + tmp = (s64)offset * (s64)alpha * (s64)sense; + rescale->offset = div_s64(tmp, (s32)1000000); + + return 0; +} + enum rescale_variant { CURRENT_SENSE_AMPLIFIER, CURRENT_SENSE_SHUNT, VOLTAGE_DIVIDER, TEMP_SENSE_RTD, + TEMP_TRANSDUCER, }; static const struct rescale_cfg rescale_cfg[] = { @@ -421,6 +448,10 @@ static const struct rescale_cfg rescale_cfg[] = { .type = IIO_TEMP, .props = rescale_temp_sense_rtd_props, }, + [TEMP_TRANSDUCER] = { + .type = IIO_TEMP, + .props = rescale_temp_transducer_props, + }, }; static const struct of_device_id rescale_match[] = { @@ -432,6 +463,8 @@ static const struct of_device_id rescale_match[] = { .data = &rescale_cfg[VOLTAGE_DIVIDER], }, { .compatible = "temperature-sense-rtd", .data = &rescale_cfg[TEMP_SENSE_RTD], }, + { .compatible = "temperature-transducer", + .data = &rescale_cfg[TEMP_TRANSDUCER], }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, rescale_match);