From: Alexis Czezar Torreno Date: Tue, 5 May 2026 09:25:06 +0000 (+0800) Subject: hwmon: (pmbus/max20830) add driver for max20830 X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=dfd47a3c885b79dba0bc2e6a47aa17ca443c4c21;p=thirdparty%2Flinux.git hwmon: (pmbus/max20830) add driver for max20830 Add support for MAX20830 step-down DC-DC switching regulator with PMBus interface. It allows monitoring of input/output voltage, output current and temperature through the PMBus serial interface. Signed-off-by: Alexis Czezar Torreno Link: https://lore.kernel.org/r/20260505-dev_max20830-v4-2-4343dcbfd7d7@analog.com [groeck: checkpatch cleanup (space before and after '-')] Signed-off-by: Guenter Roeck --- diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 2ae3316c46659..595350bfc0032 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -159,6 +159,7 @@ Hardware Monitoring Kernel Drivers max197 max20730 max20751 + max20830 max31722 max31730 max31760 diff --git a/Documentation/hwmon/max20830.rst b/Documentation/hwmon/max20830.rst new file mode 100644 index 0000000000000..936e409dcc5c0 --- /dev/null +++ b/Documentation/hwmon/max20830.rst @@ -0,0 +1,49 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Kernel driver max20830 +====================== + +Supported chips: + + * Analog Devices MAX20830 + + Prefix: 'max20830' + + Addresses scanned: - + + Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/max20830.pdf + +Author: + + - Alexis Czezar Torreno + + +Description +----------- + +This driver supports hardware monitoring for Analog Devices MAX20830 +Step-Down Switching Regulator with PMBus Interface. + +The MAX20830 is a 2.7V to 16V, 30A fully integrated step-down DC-DC switching +regulator. Through the PMBus interface, the device can monitor input/output +voltages, output current and temperature. + +The driver is a client driver to the core PMBus driver. Please see +Documentation/hwmon/pmbus.rst for details on PMBus client drivers. + +Sysfs entries +------------- + +================= ======================================== +in1_label "vin" +in1_input Measured input voltage +in1_alarm Input voltage alarm +in2_label "vout1" +in2_input Measured output voltage +in2_alarm Output voltage alarm +curr1_label "iout1" +curr1_input Measured output current +curr1_alarm Output current alarm +temp1_input Measured temperature +temp1_alarm Chip temperature alarm +================= ======================================== diff --git a/MAINTAINERS b/MAINTAINERS index 4169c5580b8aa..743e451760c9c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15683,6 +15683,8 @@ L: linux-hwmon@vger.kernel.org S: Supported W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/hwmon/pmbus/adi,max20830.yaml +F: Documentation/hwmon/max20830.rst +F: drivers/hwmon/pmbus/max20830.c MAX2175 SDR TUNER DRIVER M: Ramesh Shanmugasundaram diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig index 1f99a333abc75..8708235e3c23d 100644 --- a/drivers/hwmon/pmbus/Kconfig +++ b/drivers/hwmon/pmbus/Kconfig @@ -375,6 +375,15 @@ config SENSORS_MAX20751 This driver can also be built as a module. If so, the module will be called max20751. +config SENSORS_MAX20830 + tristate "Analog Devices MAX20830" + help + If you say yes here you get hardware monitoring support for Analog + Devices MAX20830. + + This driver can also be built as a module. If so, the module will + be called max20830. + config SENSORS_MAX31785 tristate "Maxim MAX31785 and compatibles" help diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile index 039848ecee7f5..2820e7442e32e 100644 --- a/drivers/hwmon/pmbus/Makefile +++ b/drivers/hwmon/pmbus/Makefile @@ -37,6 +37,7 @@ obj-$(CONFIG_SENSORS_MAX16601) += max16601.o obj-$(CONFIG_SENSORS_MAX17616) += max17616.o obj-$(CONFIG_SENSORS_MAX20730) += max20730.o obj-$(CONFIG_SENSORS_MAX20751) += max20751.o +obj-$(CONFIG_SENSORS_MAX20830) += max20830.o obj-$(CONFIG_SENSORS_MAX31785) += max31785.o obj-$(CONFIG_SENSORS_MAX34440) += max34440.o obj-$(CONFIG_SENSORS_MAX8688) += max8688.o diff --git a/drivers/hwmon/pmbus/max20830.c b/drivers/hwmon/pmbus/max20830.c new file mode 100644 index 0000000000000..cb2c23672166d --- /dev/null +++ b/drivers/hwmon/pmbus/max20830.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Hardware monitoring driver for Analog Devices MAX20830 + * + * Copyright (C) 2026 Analog Devices, Inc. + */ + +#include +#include +#include +#include +#include +#include "pmbus.h" + +#define MAX20830_IC_DEVICE_ID_LENGTH 9 + +static struct pmbus_driver_info max20830_info = { + .pages = 1, + .format[PSC_VOLTAGE_IN] = linear, + .format[PSC_VOLTAGE_OUT] = linear, + .format[PSC_CURRENT_OUT] = linear, + .format[PSC_TEMPERATURE] = linear, + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_TEMP | + PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | + PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP, +}; + +static int max20830_probe(struct i2c_client *client) +{ + u8 buf[I2C_SMBUS_BLOCK_MAX + 1] = {}; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BLOCK_DATA) && + !i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) + return -ENODEV; + + /* + * Use i2c_smbus_read_block_data() if supported, otherwise fall back + * to i2c_smbus_read_i2c_block_data() to support I2C controllers + * which do not support SMBus block reads. + */ + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BLOCK_DATA)) { + /* Reads 9 Data bytes from MAX20830 */ + ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to read IC_DEVICE_ID\n"); + } else { + /* Reads 1 length byte + 9 Data bytes from MAX20830 */ + ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID, + MAX20830_IC_DEVICE_ID_LENGTH + 1, + buf); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to read IC_DEVICE_ID\n"); + /* + * Moves data forward, removing the length byte, this is to + * match the format of i2c_smbus_read_block_data(). + * Also adjust return value to reflect length byte removal. + */ + memmove(buf, buf + 1, MAX20830_IC_DEVICE_ID_LENGTH); + ret = ret - 1; + } + + /* + * MAX20830 IC_DEVICE_ID sends string data "MAX20830\0". + * Return value should at least be 9 bytes of data. + */ + if (ret < MAX20830_IC_DEVICE_ID_LENGTH) + return dev_err_probe(&client->dev, -ENODEV, + "IC_DEVICE_ID too short: expected at least 9 bytes, got %d\n", + ret); + + /* 9 bytes of data, buf[0]-buf[7] = "MAX20830", buf[8] = '\0' */ + buf[MAX20830_IC_DEVICE_ID_LENGTH - 1] = '\0'; + if (strncmp(buf, "MAX20830", MAX20830_IC_DEVICE_ID_LENGTH - 1)) + return dev_err_probe(&client->dev, -ENODEV, + "Unsupported device: '%s'\n", buf); + + return pmbus_do_probe(client, &max20830_info); +} + +static const struct i2c_device_id max20830_id[] = { + {"max20830"}, + { } +}; +MODULE_DEVICE_TABLE(i2c, max20830_id); + +static const struct of_device_id max20830_of_match[] = { + { .compatible = "adi,max20830" }, + { } +}; +MODULE_DEVICE_TABLE(of, max20830_of_match); + +static struct i2c_driver max20830_driver = { + .driver = { + .name = "max20830", + .of_match_table = max20830_of_match, + }, + .probe = max20830_probe, + .id_table = max20830_id, +}; + +module_i2c_driver(max20830_driver); + +MODULE_AUTHOR("Alexis Czezar Torreno "); +MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("PMBUS");