From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 D1242C4724C for ; Sun, 3 May 2020 13:05:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A616520757 for ; Sun, 3 May 2020 13:05:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588511159; bh=g/KpiyBdHIGtCyxIHLZ2FLL0wKiuJWDBdXJg+ibzx3c=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=kgZ79wgMVAf+hZzGk8s8TF+9dujv9T5/6Uh5nWMDxiGy0TUBUR9bCyz1K13XeLqrr eb7su1DKbr0MNLX+PLW/Sa/1xbbpUdI9/eq2Pf0wqTh47c24MK3JX7xAWhAkE8fo6w h4sfAk5r36RUFL/Z3IQcp54TvU85xvT/peQVqrx4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728627AbgECNF7 (ORCPT ); Sun, 3 May 2020 09:05:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:36872 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728582AbgECNF6 (ORCPT ); Sun, 3 May 2020 09:05:58 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 765892073E; Sun, 3 May 2020 13:05:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588511158; bh=g/KpiyBdHIGtCyxIHLZ2FLL0wKiuJWDBdXJg+ibzx3c=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=A8nlAR0vGepTUJ9VOLKP4r7SrHpnVfuIxCyC68n64Lba5mNZ/BhjfsHckF3Yaurvb shGrDYlCohh9S3T5Ynfho5Ec3Es7fsfrHiMA4KBBttZUo5yQmeMhMsy6OcitGSxG6/ EkE+ceu8WsRkn//4og72ELzyXU49Khr9L/GQV1rA= Date: Sun, 3 May 2020 14:05:53 +0100 From: Jonathan Cameron To: Andreas Klinger Cc: knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, bgolaszewski@baylibre.com, linus.walleij@linaro.org, tglx@linutronix.de, allison@lohutok.net, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] iio: bmp280: fix compensation of humidity Message-ID: <20200503140553.2152709b@archlinux> In-Reply-To: <20200429184852.GA17547@arbad> References: <20200429184852.GA17547@arbad> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 29 Apr 2020 20:48:54 +0200 Andreas Klinger wrote: > Output of humidity compensation is limited to the range between 0 and > 100 percent. Add this to the compensation formula as described in the > datasheet chapter 4.2.3. More details needed... 1. Fixes tag 2. What is the result of this not being clamped? What happens if I set a value outside that range? > > Change to v1: > Thanks to Tomasz for suggesting the easier to use function clamp_val() > which is now used. Change log belongs below the --- > > Signed-off-by: Andreas Klinger > --- Here for changelog. > drivers/iio/pressure/bmp280-core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c > index 29c209cc1108..297ee2205bf6 100644 > --- a/drivers/iio/pressure/bmp280-core.c > +++ b/drivers/iio/pressure/bmp280-core.c > @@ -271,6 +271,8 @@ static u32 bmp280_compensate_humidity(struct bmp280_data *data, > + (s32)2097152) * calib->H2 + 8192) >> 14); > var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4; > > + var = clamp_val(var, 0, 419430400); > + > return var >> 12; > }; >