[PATCH 2/2] hwmon: add mpm369x driver

From: Yuxi Wang

Date: Wed Mar 18 2026 - 03:04:09 EST

Add support for mps mpm369x chip family,
which includes mpm3695-20 and mpm3690S-15.

Signed-off-by: Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/mpm369x.rst | 75 +++++++++++++++++++++
MAINTAINERS | 7 ++
drivers/hwmon/pmbus/Kconfig | 9 +++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/mpm369x.c | 115 ++++++++++++++++++++++++++++++++
6 files changed, 208 insertions(+)
create mode 100644 Documentation/hwmon/mpm369x.rst
create mode 100644 drivers/hwmon/pmbus/mpm369x.c

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index b2ca8513cfcd..340df0ccc9f1 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -190,6 +190,7 @@ Hardware Monitoring Kernel Drivers
mp5990
mp9941
mp9945
+ mpm369x
mpq8785
nct6683
nct6775
diff --git a/Documentation/hwmon/mpm369x.rst b/Documentation/hwmon/mpm369x.rst
new file mode 100644
index 000000000000..df15eb1f81c3
--- /dev/null
+++ b/Documentation/hwmon/mpm369x.rst
@@ -0,0 +1,75 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver mpm369x
+====================
+
+Supported chips:
+
+ * MPS mpm3695-20
+
+ Prefix: 'mpm3695-20'
+
+ * MPS mpm3690S-15
+
+ Prefix: 'mpm3690S-15'
+
+Author:
+
+ Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
+
+Description
+-----------
+
+This driver implements support for Monolithic Power Systems, Inc. (MPS)
+MPM3695-20 and MPM3690S-15 Controller.
+
+Device compliant with:
+
+- PMBus rev 1.3 interface.
+
+The driver exports the following attributes via the 'sysfs' files
+for input voltage:
+
+**in1_input**
+
+**in1_label**
+
+**in1_crit**
+
+**in1_crit_alarm**
+
+The driver provides the following attributes for output voltage:
+
+**in2_input**
+
+**in2_label**
+
+**in2_lcrit**
+
+**in2_lcrit_alarm**
+
+**in2_rated_max**
+
+**in2_rated_min**
+
+The driver provides the following attributes for output current:
+
+**curr1_input**
+
+**curr1_label**
+
+**curr1_max**
+
+**curr1_max_alarm**
+
+The driver provides the following attributes for temperature:
+
+**temp1_input**
+
+**temp1_crit**
+
+**temp1_crit_alarm**
+
+**temp1_max**
+
+**temp1_max_alarm**
diff --git a/MAINTAINERS b/MAINTAINERS
index 96ea84948d76..26b2949b2dd6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17948,6 +17948,13 @@ S: Maintained
F: Documentation/hwmon/mp9945.rst
F: drivers/hwmon/pmbus/mp9945.c

+MPS MPM369X DRIVER
+M: Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
+L: linux-hwmon@xxxxxxxxxxxxxxx
+S: Maintained
+F: Documentation/hwmon/mpm369x.rst
+F: drivers/hwmon/pmbus/mpm369x.c
+
MR800 AVERMEDIA USB FM RADIO DRIVER
M: Alexey Klimov <alexey.klimov@xxxxxxxxxx>
L: linux-media@xxxxxxxxxxxxxxx
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index fc1273abe357..4aadecd49209 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -517,6 +517,15 @@ config SENSORS_MP9945
This driver can also be built as a module. If so, the module will
be called mp9945.

+config SENSORS_MPM369X
+ tristate "MPS MPM369X"
+ help
+ If you say yes here you get hardware monitoring support for MPS
+ MPM369X chip family.
+
+ This driver can also be built as a module. If so, the module will
+ be called mpm369x.
+
config SENSORS_MPQ7932_REGULATOR
bool "Regulator support for MPQ7932"
depends on SENSORS_MPQ7932 && REGULATOR
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index d6c86924f887..58f38f2013b0 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_SENSORS_MP5926) += mp5926.o
obj-$(CONFIG_SENSORS_MP5990) += mp5990.o
obj-$(CONFIG_SENSORS_MP9941) += mp9941.o
obj-$(CONFIG_SENSORS_MP9945) += mp9945.o
+obj-$(CONFIG_SENSORS_MPM369X) += mpm369x.o
obj-$(CONFIG_SENSORS_MPQ7932) += mpq7932.o
obj-$(CONFIG_SENSORS_MPQ8785) += mpq8785.o
obj-$(CONFIG_SENSORS_PLI1209BC) += pli1209bc.o
diff --git a/drivers/hwmon/pmbus/mpm369x.c b/drivers/hwmon/pmbus/mpm369x.c
new file mode 100644
index 000000000000..3f1fe9c28ca7
--- /dev/null
+++ b/drivers/hwmon/pmbus/mpm369x.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * mpm369x.c - pmbus driver for mps mpm369x
+ *
+ * Copyright 2026 Monolithic Power Systems, Inc
+ *
+ * Author: Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+#define PAGE 0x01
+#define MPM369x_FUNC (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 mpm369x_read_byte_data(struct i2c_client *client, int page,
+ int reg)
+{
+ return -ENODATA;
+}
+
+static int mpm369x_read_word_data(struct i2c_client *client, int page, int phase,
+ int reg)
+{
+ int ret;
+
+ switch (reg) {
+ case PMBUS_READ_TEMPERATURE_1:
+ ret = pmbus_read_word_data(client, page, phase, reg);
+ if (ret < 0)
+ return ret;
+ /*
+ * Because the Temperature format used by the chip is a 2-byte,
+ * twos complement integer and the sign bit is bits[9].
+ * Report that signed short integer.
+ */
+ if (ret & 0x200)
+ ret = (ret & 0x1ff) | 0xfe00;
+ break;
+ default:
+ ret = -ENODATA;
+ break;
+ }
+ return ret;
+}
+
+static struct pmbus_driver_info mpm369x_info = {
+ .pages = PAGE,
+ .format[PSC_VOLTAGE_IN] = direct,
+ .format[PSC_CURRENT_OUT] = direct,
+ .format[PSC_VOLTAGE_OUT] = direct,
+ .format[PSC_TEMPERATURE] = direct,
+
+ .m[PSC_VOLTAGE_IN] = 40,
+ .b[PSC_VOLTAGE_IN] = 0,
+ .R[PSC_VOLTAGE_IN] = 0,
+
+ .m[PSC_CURRENT_OUT] = 16,
+ .b[PSC_CURRENT_OUT] = 0,
+ .R[PSC_CURRENT_OUT] = 0,
+
+ .m[PSC_VOLTAGE_OUT] = 800,
+ .b[PSC_VOLTAGE_OUT] = 0,
+ .R[PSC_VOLTAGE_OUT] = 0,
+
+ .m[PSC_TEMPERATURE] = 1,
+ .b[PSC_TEMPERATURE] = 0,
+ .R[PSC_TEMPERATURE] = 3,
+
+ .read_word_data = mpm369x_read_word_data,
+ .read_byte_data = mpm369x_read_byte_data,
+ .func[0] = MPM369x_FUNC,
+};
+
+static int mpm369x_probe(struct i2c_client *client)
+{
+ return pmbus_do_probe(client, &mpm369x_info);
+}
+
+static const struct i2c_device_id mpm369x_id[] = {
+ { "MPM3695-20", 0 },
+ { "MPM3690S-15", 1 },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, mpm369x_id);
+
+static const struct of_device_id mpm369x_of_match[] = {
+ { .compatible = "mps,mpm3695-20" },
+ { .compatible = "mps,mpm3690S-15" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mpm369x_of_match);
+
+static struct i2c_driver mpm369x_driver = {
+ .probe = mpm369x_probe,
+ .driver = {
+ .name = "mpm369x",
+ .of_match_table = mpm369x_of_match,
+ },
+ .id_table = mpm369x_id,
+};
+
+module_i2c_driver(mpm369x_driver);
+MODULE_AUTHOR("Yuxi Wang <Yuxi.Wang@xxxxxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MPS MPM369x pmbus driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");
--
2.39.2