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[73.252.146.110]) by smtp.gmail.com with ESMTPSA id m23sm7362091pfo.136.2020.11.16.17.09.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Nov 2020 17:09:56 -0800 (PST) From: rentao.bupt@gmail.com To: Jean Delvare , Guenter Roeck , Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , "David S . Miller" , Jakub Kicinski , Jesper Dangaard Brouer , John Fastabend , linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, openbmc@lists.ozlabs.org, taoren@fb.com, mikechoi@fb.com Subject: [PATCH 1/2] hwmon: (max127) Add Maxim MAX127 hardware monitoring driver Date: Mon, 16 Nov 2020 17:09:43 -0800 Message-Id: <20201117010944.28457-2-rentao.bupt@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201117010944.28457-1-rentao.bupt@gmail.com> References: <20201117010944.28457-1-rentao.bupt@gmail.com> X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tao Ren Errors-To: openbmc-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "openbmc" From: Tao Ren Add hardware monitoring driver for the Maxim MAX127 chip. MAX127 min/max range handling code is inspired by the max197 driver. Signed-off-by: Tao Ren --- drivers/hwmon/Kconfig | 9 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/max127.c | 286 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 296 insertions(+) create mode 100644 drivers/hwmon/max127.c diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 9d600e0c5584..716df51edc87 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -950,6 +950,15 @@ config SENSORS_MAX1111 This driver can also be built as a module. If so, the module will be called max1111. +config SENSORS_MAX127 + tristate "Maxim MAX127 12-bit 8-channel Data Acquisition System" + depends on I2C + help + Say y here to support Maxim's MAX127 DAS chips. + + This driver can also be built as a module. If so, the module + will be called max127. + config SENSORS_MAX16065 tristate "Maxim MAX16065 System Manager and compatibles" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 1083bbfac779..01ca5d3fbad4 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -127,6 +127,7 @@ obj-$(CONFIG_SENSORS_LTC4260) += ltc4260.o obj-$(CONFIG_SENSORS_LTC4261) += ltc4261.o obj-$(CONFIG_SENSORS_LTQ_CPUTEMP) += ltq-cputemp.o obj-$(CONFIG_SENSORS_MAX1111) += max1111.o +obj-$(CONFIG_SENSORS_MAX127) += max127.o obj-$(CONFIG_SENSORS_MAX16065) += max16065.o obj-$(CONFIG_SENSORS_MAX1619) += max1619.o obj-$(CONFIG_SENSORS_MAX1668) += max1668.o diff --git a/drivers/hwmon/max127.c b/drivers/hwmon/max127.c new file mode 100644 index 000000000000..df74a95bcf28 --- /dev/null +++ b/drivers/hwmon/max127.c @@ -0,0 +1,286 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Hardware monitoring driver for MAX127. + * + * Copyright (c) 2020 Facebook Inc. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* MAX127 Control Byte. */ +#define MAX127_CTRL_START BIT(7) +#define MAX127_CTRL_SEL_OFFSET 4 +#define MAX127_CTRL_RNG BIT(3) +#define MAX127_CTRL_BIP BIT(2) +#define MAX127_CTRL_PD1 BIT(1) +#define MAX127_CTRL_PD0 BIT(0) + +#define MAX127_NUM_CHANNELS 8 +#define MAX127_SET_CHANNEL(ch) (((ch) & 7) << (MAX127_CTRL_SEL_OFFSET)) + +#define MAX127_INPUT_LIMIT 10 /* 10V */ + +/* + * MAX127 returns 2 bytes at read: + * - the first byte contains data[11:4]. + * - the second byte contains data[3:0] (MSB) and 4 dummy 0s (LSB). + */ +#define MAX127_DATA1_SHIFT 4 + +struct max127_data { + struct mutex lock; + struct i2c_client *client; + int input_limit; + u8 ctrl_byte[MAX127_NUM_CHANNELS]; +}; + +static int max127_select_channel(struct max127_data *data, int channel) +{ + int status; + struct i2c_client *client = data->client; + struct i2c_msg msg = { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &data->ctrl_byte[channel], + }; + + status = i2c_transfer(client->adapter, &msg, 1); + if (status != 1) + return status; + + return 0; +} + +static int max127_read_channel(struct max127_data *data, int channel, u16 *vin) +{ + int status; + u8 i2c_data[2]; + struct i2c_client *client = data->client; + struct i2c_msg msg = { + .addr = client->addr, + .flags = I2C_M_RD, + .len = 2, + .buf = i2c_data, + }; + + status = i2c_transfer(client->adapter, &msg, 1); + if (status != 1) + return status; + + *vin = ((i2c_data[0] << 8) | i2c_data[1]) >> MAX127_DATA1_SHIFT; + return 0; +} + +static ssize_t max127_input_show(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + u16 vin; + int status; + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + + status = max127_select_channel(data, attr->index); + if (status) + goto exit; + + status = max127_read_channel(data, attr->index, &vin); + if (status) + goto exit; + + status = sprintf(buf, "%u", vin); + +exit: + mutex_unlock(&data->lock); + return status; +} + +static ssize_t max127_range_show(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + u8 ctrl, rng_bip; + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(dev_attr); + int rng_type = attr->nr; /* 0 for min, 1 for max */ + int channel = attr->index; + int full = data->input_limit; + int half = full / 2; + int range_table[4][2] = { + [0] = {0, half}, /* RNG=0, BIP=0 */ + [1] = {-half, half}, /* RNG=0, BIP=1 */ + [2] = {0, full}, /* RNG=1, BIP=0 */ + [3] = {-full, full}, /* RNG=1, BIP=1 */ + }; + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + ctrl = data->ctrl_byte[channel]; + mutex_unlock(&data->lock); + + rng_bip = (ctrl >> 2) & 3; + return sprintf(buf, "%d", range_table[rng_bip][rng_type]); +} + +static void max127_set_range(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] |= MAX127_CTRL_RNG; +} + +static void max127_clear_range(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] &= ~MAX127_CTRL_RNG; +} + +static void max127_set_polarity(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] |= MAX127_CTRL_BIP; +} + +static void max127_clear_polarity(struct max127_data *data, int channel) +{ + data->ctrl_byte[channel] &= ~MAX127_CTRL_BIP; +} + +static ssize_t max127_range_store(struct device *dev, + struct device_attribute *devattr, + const char *buf, + size_t count) +{ + struct max127_data *data = dev_get_drvdata(dev); + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr); + int rng_type = attr->nr; /* 0 for min, 1 for max */ + int channel = attr->index; + int full = data->input_limit; + int half = full / 2; + long input, output; + + if (kstrtol(buf, 0, &input)) + return -EINVAL; + + if (rng_type == 0) { /* min input */ + if (input <= -full) + output = -full; + else if (input < 0) + output = -half; + else + output = 0; + } else { /* max input */ + output = (input >= full) ? full : half; + } + + if (mutex_lock_interruptible(&data->lock)) + return -ERESTARTSYS; + + if (output == -full) { + max127_set_polarity(data, channel); + max127_set_range(data, channel); + } else if (output == -half) { + max127_set_polarity(data, channel); + max127_clear_range(data, channel); + } else if (output == 0) { + max127_clear_polarity(data, channel); + } else if (output == half) { + max127_clear_range(data, channel); + } else { + max127_set_range(data, channel); + } + + mutex_unlock(&data->lock); + + return count; +} + +#define MAX127_SENSOR_DEV_ATTR_DEF(ch) \ + static SENSOR_DEVICE_ATTR_RO(in##ch##_input, max127_input, ch); \ + static SENSOR_DEVICE_ATTR_2_RW(in##ch##_min, max127_range, 0, ch); \ + static SENSOR_DEVICE_ATTR_2_RW(in##ch##_max, max127_range, 1, ch) + +MAX127_SENSOR_DEV_ATTR_DEF(0); +MAX127_SENSOR_DEV_ATTR_DEF(1); +MAX127_SENSOR_DEV_ATTR_DEF(2); +MAX127_SENSOR_DEV_ATTR_DEF(3); +MAX127_SENSOR_DEV_ATTR_DEF(4); +MAX127_SENSOR_DEV_ATTR_DEF(5); +MAX127_SENSOR_DEV_ATTR_DEF(6); +MAX127_SENSOR_DEV_ATTR_DEF(7); + +#define MAX127_SENSOR_DEVICE_ATTR(ch) \ + &sensor_dev_attr_in##ch##_input.dev_attr.attr, \ + &sensor_dev_attr_in##ch##_min.dev_attr.attr, \ + &sensor_dev_attr_in##ch##_max.dev_attr.attr + +static struct attribute *max127_attrs[] = { + MAX127_SENSOR_DEVICE_ATTR(0), + MAX127_SENSOR_DEVICE_ATTR(1), + MAX127_SENSOR_DEVICE_ATTR(2), + MAX127_SENSOR_DEVICE_ATTR(3), + MAX127_SENSOR_DEVICE_ATTR(4), + MAX127_SENSOR_DEVICE_ATTR(5), + MAX127_SENSOR_DEVICE_ATTR(6), + MAX127_SENSOR_DEVICE_ATTR(7), + NULL, +}; + +ATTRIBUTE_GROUPS(max127); + +static const struct attribute_group max127_attr_groups = { + .attrs = max127_attrs, +}; + +static int max127_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int i; + struct device *hwmon_dev; + struct max127_data *data; + struct device *dev = &client->dev; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->lock); + data->input_limit = MAX127_INPUT_LIMIT; + for (i = 0; i < ARRAY_SIZE(data->ctrl_byte); i++) + data->ctrl_byte[i] = (MAX127_CTRL_START | + MAX127_SET_CHANNEL(i)); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, + client->name, data, max127_groups); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id max127_id[] = { + { "max127", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max127_id); + +static struct i2c_driver max127_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "max127", + }, + .probe = max127_probe, + .id_table = max127_id, +}; + +module_i2c_driver(max127_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mike Choi "); +MODULE_AUTHOR("Tao Ren "); +MODULE_DESCRIPTION("MAX127 Hardware Monitoring driver"); From patchwork Tue Nov 17 01:09:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tao Ren X-Patchwork-Id: 1401267 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4CZnyN3S7tz9sRK for ; Tue, 17 Nov 2020 12:13:48 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=W4EdQQK5; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4CZnyN23NSzDqP3 for ; 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[73.252.146.110]) by smtp.gmail.com with ESMTPSA id m23sm7362091pfo.136.2020.11.16.17.09.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Nov 2020 17:09:58 -0800 (PST) From: rentao.bupt@gmail.com To: Jean Delvare , Guenter Roeck , Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , "David S . Miller" , Jakub Kicinski , Jesper Dangaard Brouer , John Fastabend , linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, openbmc@lists.ozlabs.org, taoren@fb.com, mikechoi@fb.com Subject: [PATCH 2/2] docs: hwmon: Document max127 driver Date: Mon, 16 Nov 2020 17:09:44 -0800 Message-Id: <20201117010944.28457-3-rentao.bupt@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201117010944.28457-1-rentao.bupt@gmail.com> References: <20201117010944.28457-1-rentao.bupt@gmail.com> X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tao Ren Errors-To: openbmc-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "openbmc" From: Tao Ren Add documentation for max127 hardware monitoring driver. Signed-off-by: Tao Ren --- Documentation/hwmon/index.rst | 1 + Documentation/hwmon/max127.rst | 43 ++++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) create mode 100644 Documentation/hwmon/max127.rst diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 408760d13813..0a07b6000c20 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -111,6 +111,7 @@ Hardware Monitoring Kernel Drivers ltc4245 ltc4260 ltc4261 + max127 max16064 max16065 max1619 diff --git a/Documentation/hwmon/max127.rst b/Documentation/hwmon/max127.rst new file mode 100644 index 000000000000..e50225a61c1a --- /dev/null +++ b/Documentation/hwmon/max127.rst @@ -0,0 +1,43 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +Kernel driver max127 +==================== + +Author: + + * Tao Ren + +Supported chips: + + * Maxim MAX127 + + Prefix: 'max127' + + Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX127-MAX128.pdf + +Description +----------- + +The MAX127 is a multirange, 12-bit data acquisition system (DAS) providing +8 analog input channels that are independently software programmable for +a variety of ranges. The available ranges are {0,5V}, {0,10V}, {-5,5V} +and {-10,10V}. + +The MAX127 features a 2-wire, I2C-compatible serial interface that allows +communication among multiple devices using SDA and SCL lines. + +Sysfs interface +--------------- + + ============== ============================================================== + in[0-7]_input The conversion value for the corresponding channel. + RO + + in[0-7]_min The lower limit (in Volt) for the corresponding channel. + For the MAX127, it will be adjusted to -10, -5, or 0. + RW + + in[0-7]_max The higher limit (in Volt) for the corresponding channel. + For the MAX127, it will be adjusted to 0, 5, or 10. + RW + ============== ==============================================================