From patchwork Wed Apr 22 09:57:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 227127 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DBF64C55189 for ; Wed, 22 Apr 2020 10:47:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8F4C20780 for ; Wed, 22 Apr 2020 10:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552436; bh=SbJ/jaCJ3OrrVtjET4HQ68htaBYLYMg22O0Pj/OIO/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=liNbzKJiQYERinxpJpF0IjZ1unHP3MhNLZEgngOvrH1k0m4mqHNkGLP6yjOzxeOUZ emhNV8sZNs8Ijvf4mT+LG0EpYR8P/Yd8d8Ry7vCE9cdAH3ozRVR357e3sZT4lRKypL wfs77wTzjePjwKWoPRL1tr6Dwl/OJf8ZREVOXy4Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729035AbgDVKrP (ORCPT ); Wed, 22 Apr 2020 06:47:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:51538 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729010AbgDVKP5 (ORCPT ); Wed, 22 Apr 2020 06:15:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 DE3052075A; Wed, 22 Apr 2020 10:15:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550556; bh=SbJ/jaCJ3OrrVtjET4HQ68htaBYLYMg22O0Pj/OIO/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b0d98bbJWDe6pSD+pC0m3Hos7K4lFCTdmU4ucIT3vu+0fNg8yrbnGF/OYSOhbC5FJ 5p5JUjhHSwj2fCD8DEvlyo57YiCkJ6mTkWYpi0EwsODuz+UUCodL2UkT6dLS3kzhzn NLByAF/Ku/vpVpyeXJV+ANx3lOBcw2puFZ4PWmRQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Simon Goyette , =?utf-8?q?Maxime_Roussin-B=C3=A9langer?= , Guillaume Champagne , Jonathan Cameron Subject: [PATCH 4.19 57/64] iio: si1133: read 24-bit signed integer for measurement Date: Wed, 22 Apr 2020 11:57:41 +0200 Message-Id: <20200422095023.323074129@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095008.799686511@linuxfoundation.org> References: <20200422095008.799686511@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Maxime Roussin-Bélanger commit 328b50e9a0ad1fe8accdf8c19923deebab5e0c01 upstream. The chip is configured in 24 bit mode. The values read from it must always be treated as is. This fixes the issue by replacing the previous 16 bits value by a 24 bits buffer. This changes affects the value output by previous version of the driver, since the least significant byte was missing. The upper half of 16 bit values previously output are now the upper half of a 24 bit value. Fixes: e01e7eaf37d8 ("iio: light: introduce si1133") Reported-by: Simon Goyette Co-authored-by: Guillaume Champagne Signed-off-by: Maxime Roussin-Bélanger Signed-off-by: Guillaume Champagne Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/light/si1133.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) --- a/drivers/iio/light/si1133.c +++ b/drivers/iio/light/si1133.c @@ -102,6 +102,9 @@ #define SI1133_INPUT_FRACTION_LOW 15 #define SI1133_LUX_OUTPUT_FRACTION 12 #define SI1133_LUX_BUFFER_SIZE 9 +#define SI1133_MEASURE_BUFFER_SIZE 3 + +#define SI1133_SIGN_BIT_INDEX 23 static const int si1133_scale_available[] = { 1, 2, 4, 8, 16, 32, 64, 128}; @@ -234,13 +237,13 @@ static const struct si1133_lux_coeff lux } }; -static int si1133_calculate_polynomial_inner(u32 input, u8 fraction, u16 mag, +static int si1133_calculate_polynomial_inner(s32 input, u8 fraction, u16 mag, s8 shift) { return ((input << fraction) / mag) << shift; } -static int si1133_calculate_output(u32 x, u32 y, u8 x_order, u8 y_order, +static int si1133_calculate_output(s32 x, s32 y, u8 x_order, u8 y_order, u8 input_fraction, s8 sign, const struct si1133_coeff *coeffs) { @@ -276,7 +279,7 @@ static int si1133_calculate_output(u32 x * The algorithm is from: * https://siliconlabs.github.io/Gecko_SDK_Doc/efm32zg/html/si1133_8c_source.html#l00716 */ -static int si1133_calc_polynomial(u32 x, u32 y, u8 input_fraction, u8 num_coeff, +static int si1133_calc_polynomial(s32 x, s32 y, u8 input_fraction, u8 num_coeff, const struct si1133_coeff *coeffs) { u8 x_order, y_order; @@ -614,7 +617,7 @@ static int si1133_measure(struct si1133_ { int err; - __be16 resp; + u8 buffer[SI1133_MEASURE_BUFFER_SIZE]; err = si1133_set_adcmux(data, 0, chan->channel); if (err) @@ -625,12 +628,13 @@ static int si1133_measure(struct si1133_ if (err) return err; - err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(resp), - (u8 *)&resp); + err = si1133_bulk_read(data, SI1133_REG_HOSTOUT(0), sizeof(buffer), + buffer); if (err) return err; - *val = be16_to_cpu(resp); + *val = sign_extend32((buffer[0] << 16) | (buffer[1] << 8) | buffer[2], + SI1133_SIGN_BIT_INDEX); return err; } @@ -704,9 +708,9 @@ static int si1133_get_lux(struct si1133_ { int err; int lux; - u32 high_vis; - u32 low_vis; - u32 ir; + s32 high_vis; + s32 low_vis; + s32 ir; u8 buffer[SI1133_LUX_BUFFER_SIZE]; /* Activate lux channels */ @@ -719,9 +723,16 @@ static int si1133_get_lux(struct si1133_ if (err) return err; - high_vis = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; - low_vis = (buffer[3] << 16) | (buffer[4] << 8) | buffer[5]; - ir = (buffer[6] << 16) | (buffer[7] << 8) | buffer[8]; + high_vis = + sign_extend32((buffer[0] << 16) | (buffer[1] << 8) | buffer[2], + SI1133_SIGN_BIT_INDEX); + + low_vis = + sign_extend32((buffer[3] << 16) | (buffer[4] << 8) | buffer[5], + SI1133_SIGN_BIT_INDEX); + + ir = sign_extend32((buffer[6] << 16) | (buffer[7] << 8) | buffer[8], + SI1133_SIGN_BIT_INDEX); if (high_vis > SI1133_ADC_THRESHOLD || ir > SI1133_ADC_THRESHOLD) lux = si1133_calc_polynomial(high_vis, ir,