From patchwork Sat Jan 9 23:11:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Belloni X-Patchwork-Id: 12008807 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 1E9BFC433DB for ; Sat, 9 Jan 2021 23:18:30 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C7326239D1 for ; Sat, 9 Jan 2021 23:18:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C7326239D1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KvUaqTlLqTB/UAhot8zZEem0cZ14UcAQuqD6Bfdx+sg=; b=QbCWF8wIvaEWdPKjzRXYZ2zY+ Klj8X1JuJFczZv2gKKkeEzc0UWB279L2EPp3FTBygOCCshbKk09R78fynFXfih11ubG1aAvkXmgrN fga3KrZ9ER6cjJxuEh3gGBIcH9KhPHlRcY47kMDnf2no1U6H4o7mwC6tZ6xaBXSheZBfzQD7GeVEQ /IBT0pO64B2yWps7aoxPqoly94flbJ19Y3Z2Ltc5qDb1f6rNCDomWiXhcsi5fkvDSikHXBFtMfQpr Ydk4vg6P0+ZrbHlJFDCwUW2DUsZaHIgVnbg9vK7S7BPE1kpAGmKC03BtpON763SW47CQ12P6a2m+S WERAnUnSg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyNSS-0008BO-Tf; Sat, 09 Jan 2021 23:15:45 +0000 Received: from relay9-d.mail.gandi.net ([217.70.183.199]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyNPb-0006dt-Gk for linux-arm-kernel@lists.infradead.org; Sat, 09 Jan 2021 23:12:49 +0000 X-Originating-IP: 86.202.109.140 Received: from localhost (lfbn-lyo-1-13-140.w86-202.abo.wanadoo.fr [86.202.109.140]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 5DDCDFF803; Sat, 9 Jan 2021 23:12:43 +0000 (UTC) From: Alexandre Belloni To: Jonathan Cameron Subject: [PATCH v2 4/6] iio:common:ms_sensors:ms_sensors_i2c: rework CRC calculation helper Date: Sun, 10 Jan 2021 00:11:46 +0100 Message-Id: <20210109231148.1168104-5-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210109231148.1168104-1-alexandre.belloni@bootlin.com> References: <20210109231148.1168104-1-alexandre.belloni@bootlin.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210109_181248_076432_61674459 X-CRM114-Status: GOOD ( 15.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Alexandre Belloni , Lars-Peter Clausen , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Meerwald-Stadler , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The CRC calculation always happens on 8 words which is why there is an extra element in the prom array of struct ms_tp_dev. However, on ms5637 and similar, only 7 words are readable. Then, set MS_SENSORS_TP_PROM_WORDS_NB to 8 and stop passing a len parameter to ms_sensors_tp_crc_valid as this simply hide the fact that it is hardcoded. Finally, use the newly introduced hw->prom_len to know how many words can be read. Signed-off-by: Alexandre Belloni --- drivers/iio/common/ms_sensors/ms_sensors_i2c.c | 12 +++++------- drivers/iio/common/ms_sensors/ms_sensors_i2c.h | 4 ++-- 2 files changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/iio/common/ms_sensors/ms_sensors_i2c.c b/drivers/iio/common/ms_sensors/ms_sensors_i2c.c index b9e2038d05ef..872f90459e2e 100644 --- a/drivers/iio/common/ms_sensors/ms_sensors_i2c.c +++ b/drivers/iio/common/ms_sensors/ms_sensors_i2c.c @@ -493,19 +493,18 @@ EXPORT_SYMBOL(ms_sensors_ht_read_humidity); * This function is only used when reading PROM coefficients * * @prom: pointer to PROM coefficients array - * @len: length of PROM coefficients array * * Return: True if CRC is ok. */ -static bool ms_sensors_tp_crc_valid(u16 *prom, u8 len) +static bool ms_sensors_tp_crc_valid(u16 *prom) { unsigned int cnt, n_bit; u16 n_rem = 0x0000, crc_read = prom[0], crc = (*prom & 0xF000) >> 12; - prom[len - 1] = 0; + prom[MS_SENSORS_TP_PROM_WORDS_NB - 1] = 0; prom[0] &= 0x0FFF; /* Clear the CRC computation part */ - for (cnt = 0; cnt < len * 2; cnt++) { + for (cnt = 0; cnt < MS_SENSORS_TP_PROM_WORDS_NB * 2; cnt++) { if (cnt % 2 == 1) n_rem ^= prom[cnt >> 1] & 0x00FF; else @@ -537,7 +536,7 @@ int ms_sensors_tp_read_prom(struct ms_tp_dev *dev_data) { int i, ret; - for (i = 0; i < MS_SENSORS_TP_PROM_WORDS_NB; i++) { + for (i = 0; i < dev_data->hw->prom_len; i++) { ret = ms_sensors_read_prom_word( dev_data->client, MS_SENSORS_TP_PROM_READ + (i << 1), @@ -547,8 +546,7 @@ int ms_sensors_tp_read_prom(struct ms_tp_dev *dev_data) return ret; } - if (!ms_sensors_tp_crc_valid(dev_data->prom, - MS_SENSORS_TP_PROM_WORDS_NB + 1)) { + if (!ms_sensors_tp_crc_valid(dev_data->prom)) { dev_err(&dev_data->client->dev, "Calibration coefficients crc check error\n"); return -ENODEV; diff --git a/drivers/iio/common/ms_sensors/ms_sensors_i2c.h b/drivers/iio/common/ms_sensors/ms_sensors_i2c.h index f4a88148c113..f15b973f27c6 100644 --- a/drivers/iio/common/ms_sensors/ms_sensors_i2c.h +++ b/drivers/iio/common/ms_sensors/ms_sensors_i2c.h @@ -11,7 +11,7 @@ #include #include -#define MS_SENSORS_TP_PROM_WORDS_NB 7 +#define MS_SENSORS_TP_PROM_WORDS_NB 8 /** * struct ms_ht_dev - Humidity/Temperature sensor device structure @@ -47,7 +47,7 @@ struct ms_tp_dev { struct i2c_client *client; struct mutex lock; const struct ms_tp_hw_data *hw; - u16 prom[MS_SENSORS_TP_PROM_WORDS_NB + 1]; + u16 prom[MS_SENSORS_TP_PROM_WORDS_NB]; u8 res_index; };