From patchwork Wed Sep 21 12:18:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Farber, Eliav" X-Patchwork-Id: 12983649 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB7D8ECAAD8 for ; Wed, 21 Sep 2022 12:18:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229544AbiIUMSy (ORCPT ); Wed, 21 Sep 2022 08:18:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229580AbiIUMSy (ORCPT ); Wed, 21 Sep 2022 08:18:54 -0400 Received: from smtp-fw-80006.amazon.com (smtp-fw-80006.amazon.com [99.78.197.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25CE1F46; Wed, 21 Sep 2022 05:18:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1663762733; x=1695298733; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6wtC0IfCnVFcjtOxWfn6dqJt4E95Xn9a4eSwGRpOEsA=; b=mvWV7YBHyTReruwUwi6IYgp0mTH4+I7tIPCPrwr9FrCqLI/I1kOvS6lu LTCrFHkcQoeLIcmnoyMc1Xz8zE5lDhBCFhmhvv3/z7ISiiz3oYOhrJQYI ZLf37/49R5xzHa3Z3kctpZjszSjXWfEuJ0dbwZv695BPSQT5++msKcbJv g=; X-IronPort-AV: E=Sophos;i="5.93,333,1654560000"; d="scan'208";a="132383358" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-iad-1e-54c9d11f.us-east-1.amazon.com) ([10.25.36.210]) by smtp-border-fw-80006.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2022 12:18:52 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan2.iad.amazon.com [10.40.163.34]) by email-inbound-relay-iad-1e-54c9d11f.us-east-1.amazon.com (Postfix) with ESMTPS id 87DF6C042C; Wed, 21 Sep 2022 12:18:49 +0000 (UTC) Received: from EX19D013UWB001.ant.amazon.com (10.13.138.52) by EX13MTAUWB001.ant.amazon.com (10.43.161.207) with Microsoft SMTP Server (TLS) id 15.0.1497.38; Wed, 21 Sep 2022 12:18:45 +0000 Received: from EX13MTAUWB001.ant.amazon.com (10.43.161.207) by EX19D013UWB001.ant.amazon.com (10.13.138.52) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1118.12; Wed, 21 Sep 2022 12:18:45 +0000 Received: from dev-dsk-farbere-1a-46ecabed.eu-west-1.amazon.com (172.19.116.181) by mail-relay.amazon.com (10.43.161.249) with Microsoft SMTP Server id 15.0.1497.38 via Frontend Transport; Wed, 21 Sep 2022 12:18:45 +0000 Received: by dev-dsk-farbere-1a-46ecabed.eu-west-1.amazon.com (Postfix, from userid 14301484) id A72534B01; Wed, 21 Sep 2022 12:18:44 +0000 (UTC) From: Eliav Farber To: , , , , , CC: , , , "Andy Shevchenko" , kernel test robot Subject: [PATCH v6 1/2] hwmon: (mr75203) modify the temperature equation according to series 5 datasheet Date: Wed, 21 Sep 2022 12:18:43 +0000 Message-ID: <20220921121844.8059-2-farbere@amazon.com> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220921121844.8059-1-farbere@amazon.com> References: <20220921121844.8059-1-farbere@amazon.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Modify the equation and coefficients used to convert the digital output to temperature according to series 5 of the Moortec Embedded Temperature Sensor (METS) datasheet: T = G + H * (n / cal5 - 0.5) + J * F Where: *) G = 60, H = 200, cal5 = 4094, J = -0.1. *) F = frequency clock in MHz. *) n is the digital output. In code, the G, H and J coefficients are multiplied by a factor of 1000 to get the temperature in milli-Celsius. Final result is clamped in case it exceeds min/max thresholds. Change is done since it is unclear where the current equation and coefficients came from. Signed-off-by: Eliav Farber Reviewed-by: Andy Shevchenko Reported-by: kernel test robot Tested-by: Sudip Mukherjee --- V5 -> V4: - fix undefined reference to `__divdi3' V4 -> V3: - Change 'not clear' to 'unclear' in commit message. - Add _mC prefix to temperature mix/max defines. - Add SERIES5 to coefficient defines. V3 -> V2: - Protect from overflow. - Add temperature clamping. - Add better documentation. drivers/hwmon/mr75203.c | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) diff --git a/drivers/hwmon/mr75203.c b/drivers/hwmon/mr75203.c index 8a6ae72fed20..fb262fd2b511 100644 --- a/drivers/hwmon/mr75203.c +++ b/drivers/hwmon/mr75203.c @@ -102,13 +102,19 @@ #define PVT_POLL_DELAY_US 20 #define PVT_POLL_TIMEOUT_US 20000 -#define PVT_H_CONST 100000 -#define PVT_CAL5_CONST 2047 -#define PVT_G_CONST 40000 #define PVT_CONV_BITS 10 #define PVT_N_CONST 90 #define PVT_R_CONST 245805 +#define PVT_TEMP_MIN_mC -40000 +#define PVT_TEMP_MAX_mC 125000 + +/* Temperature coefficients for series 5 */ +#define PVT_SERIES5_H_CONST 200000 +#define PVT_SERIES5_G_CONST 60000 +#define PVT_SERIES5_J_CONST -100 +#define PVT_SERIES5_CAL5_CONST 4094 + #define PRE_SCALER_X1 1 #define PRE_SCALER_X2 2 @@ -174,13 +180,26 @@ static umode_t pvt_is_visible(const void *data, enum hwmon_sensor_types type, return 0; } +static long pvt_calc_temp(struct pvt_device *pvt, u32 nbs) +{ + /* + * Convert the register value to degrees centigrade temperature: + * T = G + H * (n / cal5 - 0.5) + J * F + */ + s64 tmp = PVT_SERIES5_G_CONST + + div_s64(PVT_SERIES5_H_CONST * (s64)nbs, PVT_SERIES5_CAL5_CONST) - + PVT_SERIES5_H_CONST / 2 + + div_s64(PVT_SERIES5_J_CONST * (s64)pvt->ip_freq, HZ_PER_MHZ); + + return clamp_val(tmp, PVT_TEMP_MIN_mC, PVT_TEMP_MAX_mC); +} + static int pvt_read_temp(struct device *dev, u32 attr, int channel, long *val) { struct pvt_device *pvt = dev_get_drvdata(dev); struct regmap *t_map = pvt->t_map; u32 stat, nbs; int ret; - u64 tmp; switch (attr) { case hwmon_temp_input: @@ -201,9 +220,7 @@ static int pvt_read_temp(struct device *dev, u32 attr, int channel, long *val) * Convert the register value to * degrees centigrade temperature */ - tmp = nbs * PVT_H_CONST; - do_div(tmp, PVT_CAL5_CONST); - *val = tmp - PVT_G_CONST - pvt->ip_freq; + *val = pvt_calc_temp(pvt, nbs); return 0; default: @@ -337,7 +354,7 @@ static int pvt_init(struct pvt_device *pvt) (key >> 1) << CLK_SYNTH_HI_SFT | (key >> 1) << CLK_SYNTH_HOLD_SFT | CLK_SYNTH_EN; - pvt->ip_freq = sys_freq * 100 / (key + 2); + pvt->ip_freq = clk_get_rate(pvt->clk) / (key + 2); if (t_num) { ret = regmap_write(t_map, SDIF_SMPL_CTRL, 0x0);