[PATCH v2 2/2] hwmon: (pmbus/max20830) add driver for max20830

Alexis Czezar Torreno
2026-04-16T08:00:25Z

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 <alexisczezar.torreno@analog.com>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/max20830.rst | 49 +++++++++++++++++++++++
MAINTAINERS | 2 +
drivers/hwmon/pmbus/Kconfig | 9 +++++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/max20830.c | 86 ++++++++++++++++++++++++++++++++++++++++
6 files changed, 148 insertions(+)

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index 8b655e5d6b68b90c697a52c7bf526e81d370caf7..56f7eb761be76dd627a2f34135abad05203b0582 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -158,6 +158,7 @@ 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 0000000000000000000000000000000000000000..936e409dcc5c0898dde27d782308d4a7e1357e73
--- /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 <alexisczezar.torreno@analog.com>
+
+
+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 031c743e979521a92ed9ac67915c178ce31727bd..d6a6745e2dae29c3b8f80bbe61c54a2f5ecd9f47 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15585,6 +15585,8 @@ 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 <rashanmu@gmail.com>
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 8f4bff375ecbc355f5ed3400855c2852ec2aa5ef..987705bf45b75b7b91ccc469247909f3c3f53d77 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -365,6 +365,15 @@ 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 7129b62bc00f8a2e98de14004997752a856dfda2..bc52f930e0825a902a0dd1c9e2b44f2e8d577c35 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -36,6 +36,7 @@ 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 0000000000000000000000000000000000000000..21ea8b59150cb0564f1776ee08131bad7fdef003
--- /dev/null
+++ b/drivers/hwmon/pmbus/max20830.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hardware monitoring driver for Analog Devices MAX20830
+ *
+ * Copyright (C) 2026 Analog Devices, Inc.
+ */
+
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+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];
+ u8 len;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+ return -ENODEV;
+
+ /*
+ * Use i2c_smbus_read_i2c_block_data() instead of
+ * i2c_smbus_read_block_data() to support I2C controllers
+ * which do not support SMBus block reads.
+ */
+ ret = i2c_smbus_read_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
+ I2C_SMBUS_BLOCK_MAX, buf);
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret,
+ "Failed to read IC_DEVICE_ID\n");
+
+ /* First byte is the block length. */
+ len = buf[0];
+ if (len != 9)
+ return dev_err_probe(&client->dev, -ENODEV,
+ "Unexpected IC_DEVICE_ID response\n");
+
+ buf[len] = '\0';
+ if (strncmp(buf + 1, "MAX20830", 8))
+ return dev_err_probe(&client->dev, -ENODEV,
+ "Unsupported device: '%s'\n", buf + 1);
+
+ 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 <alexisczezar.torreno@analog.com>");
+MODULE_DESCRIPTION("PMBus driver for Analog Devices MAX20830");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");

--
2.34.1