From patchwork Thu May 23 12:10:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Radu Sabau X-Patchwork-Id: 13671691 Received: from mx0a-00128a01.pphosted.com (mx0a-00128a01.pphosted.com [148.163.135.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A752913B7A6; Thu, 23 May 2024 12:11:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.135.77 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716466309; cv=none; b=MYjUiaSxoJudhl1ZGbCqbzWjoFJ7OaLvt7o+Fwl6Rmt0U2fd8ZDI54Juybfr2kN5R2m1iVtY0bfT6O79PBPqWrT3hFVKXa8OpZae8Ki5Kjkd4Y0F5lk4YSnzRMxnQIccwYzBvdMPBvB8dnYUtPa/04DsXbI8qdRDew0EcGaVWaQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716466309; c=relaxed/simple; bh=vALmUqA5Wog+zqLtOkN/QaJNWqWwzNf0U+orGc33tQU=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=EXXXCSSf6o3bQ5nmEpYYtco/I2s/Qaizrw0wido3EAoDe6euGg3emrpX1psCyVbNVAHUWq3ks9a2WBQxE8NW2WzXOhCs8/89XoBC2l82oY9YwsxwnCGZOKxIh65oaxSPZaVpZ44C/WoItuF4/B9xnr4p+TgISo7cJEFbEx6kANE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com; spf=pass smtp.mailfrom=analog.com; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b=bqSOLSqC; arc=none smtp.client-ip=148.163.135.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=analog.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b="bqSOLSqC" Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 44NA1Zhg011307; Thu, 23 May 2024 08:11:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=analog.com; h=cc :content-transfer-encoding:content-type:date:from:message-id :mime-version:subject:to; s=DKIM; bh=EdFbmO6SN0AAHhccZL9llajYuxh Q6Qu7Stq9Fo0o8LI=; b=bqSOLSqCwZLDDbX8JoO7RBW97SCn8XuOxI+27TcJokM KLZUG350eSX14K4wx79ihiNf5eW4YWaLmJ6YcfzHHIFDztXbS7krYkOrsvCMx2a2 v0R4N9RLY1KrsUShFhQsmtLXmk7bcKQswvR1sJgNs+Nwtj8IQg9jo32a5Gmxcqfi B3UfprmhdtVLWHuTK/fWQby5z9RQFJkyhV6UYZBhPPhB8aqqpsEk9xGuYdK/6m82 X7V2sAunikz7si4j+nEwV0RXdBBWMDXJyJQ6PKoUbn47b1tSD3QsLPX3el6qsiRW mjrceCRoa0rE9+CX+sYOMMeCeu+04S7bCIb590gqUUw== Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com (PPS) with ESMTPS id 3y9xwuhgt0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 23 May 2024 08:11:28 -0400 (EDT) Received: from ASHBMBX9.ad.analog.com (ASHBMBX9.ad.analog.com [10.64.17.10]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 44NCBR1k024808 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 23 May 2024 08:11:27 -0400 Received: from ASHBMBX8.ad.analog.com (10.64.17.5) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Thu, 23 May 2024 08:11:26 -0400 Received: from zeus.spd.analog.com (10.66.68.11) by ashbmbx8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server id 15.2.986.14 via Frontend Transport; Thu, 23 May 2024 08:11:26 -0400 Received: from radu.ad.analog.com ([10.48.65.189]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 44NCBF7Y029999; Thu, 23 May 2024 08:11:18 -0400 From: Radu Sabau To: Jean Delvare , Guenter Roeck , Jonathan Corbet , , , CC: Radu Sabau Subject: [PATCH v2] drivers: hwmon: max31827: Add PEC support Date: Thu, 23 May 2024 15:10:56 +0300 Message-ID: <20240523121057.5689-1-radu.sabau@analog.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-GUID: h9Tr9HCB91KG15ivkVUtZyfpR07p5NaD X-Proofpoint-ORIG-GUID: h9Tr9HCB91KG15ivkVUtZyfpR07p5NaD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.650,FMLib:17.12.28.16 definitions=2024-05-23_07,2024-05-23_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 phishscore=0 mlxlogscore=999 spamscore=0 clxscore=1015 suspectscore=0 lowpriorityscore=0 impostorscore=0 adultscore=0 bulkscore=0 malwarescore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2405010000 definitions=main-2405230083 Add support for PEC by attaching PEC attribute to the i2c device. Add pec_store and pec_show function for accesing the "pec" file. Signed-off-by: Radu Sabau --- Documentation/hwmon/max31827.rst | 13 +++++-- drivers/hwmon/max31827.c | 64 ++++++++++++++++++++++++++++++++ 2 files changed, 74 insertions(+), 3 deletions(-) diff --git a/Documentation/hwmon/max31827.rst b/Documentation/hwmon/max31827.rst index 44ab9dc064cb..9c11a9518c67 100644 --- a/Documentation/hwmon/max31827.rst +++ b/Documentation/hwmon/max31827.rst @@ -131,7 +131,14 @@ The Fault Queue bits select how many consecutive temperature faults must occur before overtemperature or undertemperature faults are indicated in the corresponding status bits. -Notes ------ +PEC Support +----------- + +When reading a register value, the PEC byte is computed and sent by the chip. + +PEC on word data transaction respresents a signifcant increase in bandwitdh +usage (+33% for both write and reads) in normal conditions. -PEC is not implemented. +Since this operation implies there will be an extra delay to each +transaction, PEC can be disabled or enabled through sysfs. +Just write 1 to the "pec" file for enabling PEC and 0 for disabling it. diff --git a/drivers/hwmon/max31827.c b/drivers/hwmon/max31827.c index f8a13b30f100..e86f8890ee72 100644 --- a/drivers/hwmon/max31827.c +++ b/drivers/hwmon/max31827.c @@ -24,6 +24,7 @@ #define MAX31827_CONFIGURATION_1SHOT_MASK BIT(0) #define MAX31827_CONFIGURATION_CNV_RATE_MASK GENMASK(3, 1) +#define MAX31827_CONFIGURATION_PEC_EN_MASK BIT(4) #define MAX31827_CONFIGURATION_TIMEOUT_MASK BIT(5) #define MAX31827_CONFIGURATION_RESOLUTION_MASK GENMASK(7, 6) #define MAX31827_CONFIGURATION_ALRM_POL_MASK BIT(8) @@ -475,6 +476,54 @@ static ssize_t temp1_resolution_store(struct device *dev, static DEVICE_ATTR_RW(temp1_resolution); +static ssize_t pec_show(struct device *dev, struct device_attribute *devattr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + + return scnprintf(buf, PAGE_SIZE, "%d\n", !!(client->flags & I2C_CLIENT_PEC)); +} + +static ssize_t pec_store(struct device *dev, struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct max31827_state *st = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(dev); + unsigned int val; + int err; + + err = kstrtouint(buf, 10, &val); + if (err < 0) + return err; + + switch (val) { + case 0: + err = regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG, + MAX31827_CONFIGURATION_PEC_EN_MASK, + val); + if (err) + return err; + + client->flags &= ~I2C_CLIENT_PEC; + break; + case 1: + err = regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG, + MAX31827_CONFIGURATION_PEC_EN_MASK, + val); + if (err) + return err; + + client->flags |= I2C_CLIENT_PEC; + break; + default: + return -EINVAL; + } + + return count; +} + +static DEVICE_ATTR_RW(pec); + static struct attribute *max31827_attrs[] = { &dev_attr_temp1_resolution.attr, NULL @@ -578,6 +627,11 @@ static int max31827_init_client(struct max31827_state *st, return regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, res); } +static void max31827_remove_pec(void *dev) +{ + device_remove_file(dev, &dev_attr_pec); +} + static const struct hwmon_channel_info *max31827_info[] = { HWMON_CHANNEL_INFO(temp, HWMON_T_ENABLE | HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MIN_HYST | HWMON_T_MIN_ALARM | @@ -627,6 +681,16 @@ static int max31827_probe(struct i2c_client *client) if (err) return err; + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_PEC)) { + err = device_create_file(dev, &dev_attr_pec); + if (err) + return err; + + err = devm_add_action_or_reset(dev, max31827_remove_pec, dev); + if (err) + return err; + } + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, st, &max31827_chip_info, max31827_groups);