diff --git a/MAINTAINERS b/MAINTAINERS
index 936490dcc97b..bf3c6c3c0492 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8042,6 +8042,12 @@ S:	Maintained
 F:	Documentation/ABI/testing/sysfs-driver-intel-m10-bmc-sec-update
 F:	drivers/fpga/intel-m10-bmc-sec-update.c
 
+MICROCHIP EMC230X PWM-FAN CONTROLLER DRIVERS
+M:	Mathew McBride <matt@traverse.com.au>
+L:	linux-hwmon@vger.kernel.org
+S:	Maintained
+F:	drivers/hwmon/emc230x.c
+
 MICROCHIP POLARFIRE FPGA DRIVERS
 M:	Conor Dooley <conor.dooley@microchip.com>
 R:	Ivan Bornyakov <i.bornyakov@metrotek.ru>
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index e70d9614bec2..e8da7793367c 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1775,6 +1775,19 @@ config SENSORS_EMC1403
 	  Threshold values can be configured using sysfs.
 	  Data from the different diodes are accessible via sysfs.
 
+config SENSORS_EMC230X
+	tristate "Microchip EMC230X fan controllers"
+	depends on I2C
+	help
+	  If you say yes here you get support for the Microchip (SMSC)
+	  EMC230x family of RPM-PWM fan controllers.
+
+	  When the thermal subsystem is enabled, this driver can
+	  be used as a cooling-device for a thermal zone.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called emc230x.
+
 config SENSORS_EMC2103
 	tristate "SMSC EMC2103"
 	depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 007e829d1d0d..f87f8323493b 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_SENSORS_DRIVETEMP)	+= drivetemp.o
 obj-$(CONFIG_SENSORS_DS620)	+= ds620.o
 obj-$(CONFIG_SENSORS_DS1621)	+= ds1621.o
 obj-$(CONFIG_SENSORS_EMC1403)	+= emc1403.o
+obj-$(CONFIG_SENSORS_EMC230X)	+= emc230x.o
 obj-$(CONFIG_SENSORS_EMC2103)	+= emc2103.o
 obj-$(CONFIG_SENSORS_EMC6W201)	+= emc6w201.o
 obj-$(CONFIG_SENSORS_F71805F)	+= f71805f.o
diff --git a/drivers/hwmon/emc230x.c b/drivers/hwmon/emc230x.c
new file mode 100644
index 000000000000..1207acf62d2c
--- /dev/null
+++ b/drivers/hwmon/emc230x.c
@@ -0,0 +1,587 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Microchip (formerly SMSC) EMC230X family RPM fan controller driver
+ * For EMC2301/2/5 controllers
+ * Copyright (C) 2021-2022 Traverse Technologies
+ */
+
+/*
+ * This driver has two components:
+ * - hwmon (read/write fan rpm values)
+ * - thermal (set fan rpm speeds for cooling purposes)
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/thermal.h>
+
+#define TACH_HIGH_MASK	GENMASK(12, 5)
+#define TACH_LOW_MASK	GENMASK(4, 0)
+
+#define EMC230X_FAN_STALL_STATUS_REG		0x25
+#define EMC230X_FAN_SPIN_FAIL_STATUS_REG	0x26
+#define EMC230X_FAN_DRIVE_FAIL_STATUS_REG	0x27
+
+#define EMC230X_PWM_FAN_DRIVE_REG(channel)	(0x30 + (channel * 0x10))
+#define EMC230X_FAN_CONFIG_REG(channel)		(0x32 + (channel * 0x10))
+#define EMC230X_FAN_CONFIG_ENABLE_CLOSED_LOOP	BIT(7)
+#define EMC230X_TACH_TARGET_LOW_REG(channel)	(0x3C + (channel * 0x10))
+#define EMC230X_TACH_READ_HIGH_REG(channel)	(0x3E + (channel * 0x10))
+
+#define THERMAL_DEVICE_COOLING_MAX_STEPS	7
+#define MAX_COOLING_DEV_NAME_LEN 16
+/*
+ * Factor by equations [2] and [3] from data sheet; valid for fans where the
+ * number of edges equals (poles * 2 + 1).
+ */
+#define FAN_RPM_FACTOR 3932160
+
+struct emc230x_cooling_device {
+	struct emc230x_data *parent;
+	char name[MAX_COOLING_DEV_NAME_LEN];
+	struct thermal_cooling_device *tcdev;
+	u8 channel;
+	u8 cur_state;
+	u16 cooling_step;
+	u16 min_rpm;
+	u16 max_rpm;
+};
+
+struct emc230x_data {
+	struct device *hwmon_dev;
+	struct i2c_client *i2c_client;
+	u8 device_max_channels;
+};
+
+static const struct i2c_device_id emc230x_ids[] = {
+	{ "emc2301", 1 },
+	{ "emc2302", 2 },
+	{ "emc2303", 3 },
+	{ "emc2305", 5 },
+	{ /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(i2c, emc230x_ids);
+
+static int emc2301_read_fan_tach(struct device *dev,
+				 int channel,
+				 u16 *tach)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+	u8 channel_high_register_addr;
+	u16 combined_reading;
+	u8 channel_bytes[2];
+	int bytes_read;
+
+	if ((channel + 1) > priv->device_max_channels)
+		return -EINVAL;
+
+	channel_high_register_addr = EMC230X_TACH_READ_HIGH_REG(channel);
+
+	bytes_read = i2c_smbus_read_i2c_block_data(priv->i2c_client,
+						   channel_high_register_addr,
+						   2, &channel_bytes[0]);
+	if (bytes_read < 2) {
+		dev_err(dev,
+			"%s: error %d reading channel %d tach register",
+			__func__, bytes_read, channel);
+		return bytes_read;
+	}
+
+	/* First byte (register) is the high byte, second low byte */
+	combined_reading = ((u16)(channel_bytes[0]) << 5) | (channel_bytes[1] >> 3);
+
+	*tach = combined_reading;
+
+	return 0;
+}
+
+static int emc230x_show_fan_rpm(struct device *dev, int channel, long *val)
+{
+	long fan_rpm;
+	u16 channel_tach;
+	int ret;
+
+	ret = emc2301_read_fan_tach(dev, channel, &channel_tach);
+	if (ret)
+		return ret;
+
+	fan_rpm = (FAN_RPM_FACTOR * 2) / channel_tach;
+	*val = fan_rpm;
+
+	return 0;
+}
+
+static int emc230x_write_fan_rpm_target(struct i2c_client *client,
+					int channel, long target_rpm)
+{
+	int ret;
+	u16 target_tach;
+	u8 tach_channel_reg_addr;
+	u8 tach_bytes[2];
+
+	tach_channel_reg_addr = EMC230X_TACH_TARGET_LOW_REG(channel);
+	/* 0 RPM is a special case - writing 0xFFF0 will turn off the fan */
+	if (target_rpm == 0) {
+		tach_bytes[0] = 0xF0;
+		tach_bytes[1] = 0xFF;
+	} else {
+		target_tach = (FAN_RPM_FACTOR * 2) / target_rpm;
+		tach_bytes[0] = (target_tach & TACH_LOW_MASK) << 3;
+		tach_bytes[1] = (target_tach & TACH_HIGH_MASK) >> 5;
+	}
+
+	ret = i2c_smbus_write_i2c_block_data(client,
+					     tach_channel_reg_addr,
+					     2, &tach_bytes[0]);
+	if (ret != 2)
+		return ret;
+
+	return 0;
+}
+
+static int emc230x_set_fan_rpm(struct device *dev, int channel, long target_rpm)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+
+	if ((channel + 1) > priv->device_max_channels)
+		return -ENODEV;
+
+	dev_dbg(dev,
+		"%s: setting channel %d rpm to %ld\n",
+		__func__, channel, target_rpm);
+
+	return emc230x_write_fan_rpm_target(priv->i2c_client, channel, target_rpm);
+}
+
+static int emc230x_read_fan_rpm_target_value(struct i2c_client *client,
+					     int channel,
+					     long *target_rpm_value)
+{
+	int ret;
+	u8 tach_channel_reg_addr;
+	u8 tach_bytes[2];
+	u16 combined_reading;
+	long rpm_target;
+
+	tach_channel_reg_addr = EMC230X_TACH_TARGET_LOW_REG(channel);
+	ret = i2c_smbus_read_i2c_block_data(client,
+					    tach_channel_reg_addr,
+					    2, &tach_bytes[0]);
+	if (ret != 2)
+		return ret;
+
+	/* This is different from the RPM speed registers,
+	 * the low byte is the first register read
+	 */
+	if (tach_bytes[1] == 0xFF && tach_bytes[0] == 0xF0) {
+		rpm_target = 0;
+	} else {
+		combined_reading = ((u16)(tach_bytes[1]) << 5) | (tach_bytes[0] >> 3);
+		rpm_target = (FAN_RPM_FACTOR * 2) / combined_reading;
+	}
+
+	*target_rpm_value = rpm_target;
+	return 0;
+}
+
+static int emc230x_show_fan_rpm_target(struct device *dev, int channel,
+				       long *value)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+
+	if ((channel + 1) > priv->device_max_channels)
+		return -EINVAL;
+
+	return emc230x_read_fan_rpm_target_value(priv->i2c_client,
+						 channel,
+						 value);
+}
+
+static int emc230x_enable_rpm_control(struct device *dev,
+				      struct i2c_client *client,
+				      int channel, bool enable)
+{
+	u8 fan_config_reg_addr;
+	u8 fan_config_reg_val;
+	int ret;
+
+	fan_config_reg_addr = EMC230X_FAN_CONFIG_REG(channel);
+
+	fan_config_reg_val = i2c_smbus_read_byte_data(client, fan_config_reg_addr);
+	if (enable)
+		fan_config_reg_val |= EMC230X_FAN_CONFIG_ENABLE_CLOSED_LOOP;
+	else
+		fan_config_reg_val &= ~(EMC230X_FAN_CONFIG_ENABLE_CLOSED_LOOP);
+
+	ret = i2c_smbus_write_byte_data(client, fan_config_reg_addr, fan_config_reg_val);
+	if (ret) {
+		dev_err(dev,
+			"Unable to write fan configuration register %02X\n",
+			fan_config_reg_addr);
+		return ret;
+	}
+
+	/* If RPM drive not enabled, set PWM cycle (non-closed loop) to 100% */
+	if (!enable)
+		ret = i2c_smbus_write_byte_data(client,
+						EMC230X_PWM_FAN_DRIVE_REG(channel),
+						0xFF);
+
+	return ret;
+};
+
+static int emc230x_write_rpm_control(struct device *dev,
+				     int channel,
+				     long value)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+	bool enable_rpm_control = (value == 1) ? true : false;
+
+	return emc230x_enable_rpm_control(dev, priv->i2c_client,
+					  channel,
+					  enable_rpm_control);
+}
+
+static int emc230x_read_is_rpm_control(struct device *dev,
+				       int channel,
+				       long *value)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+	u8 fan_config_reg_addr;
+	u32 fan_config_reg_val;
+
+	fan_config_reg_addr = EMC230X_FAN_CONFIG_REG(channel);
+
+	fan_config_reg_val = i2c_smbus_read_byte_data(priv->i2c_client,
+						      fan_config_reg_addr);
+	if (fan_config_reg_val < 0)
+		return fan_config_reg_val;
+
+	if (fan_config_reg_val & EMC230X_FAN_CONFIG_ENABLE_CLOSED_LOOP)
+		*value = 1;
+	else
+		*value = 0;
+
+	return 0;
+}
+
+
+static int emc230x_read_fault(struct i2c_client *client,
+			      int channel,
+			      long *retval)
+{
+	int ret;
+	u8 fan_mask;
+	u8 fan_status_registers[3];
+	long fault_value = 0;
+
+	/* Read the three fan fault registers (stall,spin,drive)
+	 * consecutively
+	 */
+	ret = i2c_smbus_read_i2c_block_data(client,
+					    EMC230X_FAN_STALL_STATUS_REG,
+					    3, &fan_status_registers[0]);
+	if (ret != 3)
+		return ret;
+
+	fan_mask = (1 << channel);
+
+	if (fan_status_registers[0] & fan_mask) /* Stall */
+		fault_value = 1;
+	if (fan_status_registers[1] & fan_mask) /* Spin */
+		fault_value |= (1<<1);
+	if (fan_status_registers[2] & fan_mask) /* Drive */
+		fault_value |= (1<<2);
+	*retval = fault_value;
+
+	return 0;
+}
+
+static int emc230x_show_faults(struct device *dev, int channel,
+			       long *value)
+{
+	struct emc230x_data *priv = dev_get_drvdata(dev);
+
+	return emc230x_read_fault(priv->i2c_client, channel, value);
+}
+
+static const struct hwmon_channel_info *emc2301_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET,
+			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_TARGET),
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_ENABLE,
+			   HWMON_PWM_ENABLE,
+			   HWMON_PWM_ENABLE,
+			   HWMON_PWM_ENABLE,
+			   HWMON_PWM_ENABLE),
+	NULL
+};
+
+static umode_t emc230x_hwmon_is_visible(const void *data,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int channel)
+{
+	struct emc230x_data *priv = (struct emc230x_data *)data;
+
+	if ((channel + 1) > priv->device_max_channels)
+		return 0;
+
+	switch (type) {
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+		case hwmon_fan_fault:
+			return 0444;
+		case hwmon_fan_target:
+			return 0644;
+		default:
+			return 0;
+		}
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_enable:
+			return 0644;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static int emc230x_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			      u32 attr, int channel, long *value)
+{
+	switch (type) {
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+			return emc230x_show_fan_rpm(dev, channel, value);
+		case hwmon_fan_target:
+			return emc230x_show_fan_rpm_target(dev, channel, value);
+		case hwmon_fan_fault:
+			return emc230x_show_faults(dev, channel, value);
+		default:
+			return 0;
+		}
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_enable:
+			return emc230x_read_is_rpm_control(dev, channel, value);
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static int emc230x_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long value)
+{
+	if (type == hwmon_fan && attr == hwmon_fan_target)
+		return emc230x_set_fan_rpm(dev, channel, value);
+	else if (type == hwmon_pwm && attr == hwmon_pwm_enable)
+		return emc230x_write_rpm_control(dev, channel, value);
+
+	return -EINVAL;
+}
+
+static int emc230x_thermal_get_max_state(struct thermal_cooling_device *tcdev,
+					 unsigned long *state)
+{
+	*state = THERMAL_DEVICE_COOLING_MAX_STEPS;
+	return 0;
+}
+
+static int emc230x_thermal_get_cur_state(struct thermal_cooling_device *tcdev,
+					 unsigned long *state)
+{
+	struct emc230x_cooling_device *cdev = tcdev->devdata;
+
+	*state = cdev->cur_state;
+
+	return 0;
+}
+
+static int emc230x_thermal_set_cur_state(struct thermal_cooling_device *tcdev,
+					 unsigned long state)
+{
+	struct emc230x_cooling_device *cdev = tcdev->devdata;
+	struct emc230x_data *parent_device = cdev->parent;
+	struct i2c_client *client = parent_device->i2c_client;
+	int ret;
+	u16 fan_rpm;
+
+	if (state > 0)
+		fan_rpm = cdev->min_rpm + ((state + 1) * cdev->cooling_step);
+	else
+		fan_rpm = cdev->min_rpm;
+
+	ret = emc230x_write_fan_rpm_target(client, cdev->channel, fan_rpm);
+	if (!ret)
+		cdev->cur_state = state;
+
+	return ret;
+}
+
+static const struct thermal_cooling_device_ops emc230x_fan_cooling_ops = {
+	.get_max_state = emc230x_thermal_get_max_state,
+	.get_cur_state = emc230x_thermal_get_cur_state,
+	.set_cur_state = emc230x_thermal_set_cur_state
+};
+
+/*
+ * emc230x_create_fan() - create a thermal device from FDT configuration
+ */
+static int emc230x_create_fan(struct device *dev,
+			      struct device_node *child,
+			      struct emc230x_data *priv)
+{
+	int ret;
+	u32 channel;
+	u16 min_rpm, max_rpm, cooling_range;
+	struct emc230x_cooling_device *faninfo;
+
+	ret = of_property_read_u32(child, "reg", &channel);
+	if (ret)
+		return ret;
+
+	if ((channel + 1) > priv->device_max_channels)
+		return -EINVAL;
+
+	/* If there are any DT attributes introduced that are not
+	 * directly related to thermal subsystem integration
+	 * (such as configuring PWM modes, or fan pole settings),
+	 * they should be processed here before the #cooling-cells
+	 * check
+	 */
+	ret = of_property_count_u32_elems(child, "#cooling-cells");
+	if (ret < 1)
+		return 0;
+
+	ret = of_property_read_u16(child, "min-rpm", &min_rpm);
+	if (ret) {
+		dev_err(dev,
+			"%s: missing or invalid \"min-rpm\" property (channel=%d,err=%d)\n",
+			__func__, channel, ret);
+		return ret;
+	}
+
+	ret = of_property_read_u16(child, "max-rpm", &max_rpm);
+	if (ret) {
+		dev_err(dev,
+			"%s: missing or invalid \"min-rpm\" property (channel=%d,err=%d)\n",
+			__func__, channel, ret);
+		return ret;
+	}
+
+	faninfo = devm_kzalloc(dev, sizeof(*faninfo), GFP_KERNEL);
+
+	faninfo->parent = priv;
+	faninfo->channel = (u8)channel;
+	faninfo->min_rpm = min_rpm;
+	faninfo->max_rpm = max_rpm;
+
+	cooling_range = max_rpm - min_rpm;
+	faninfo->cooling_step = cooling_range / (THERMAL_DEVICE_COOLING_MAX_STEPS+1);
+	faninfo->cur_state = THERMAL_DEVICE_COOLING_MAX_STEPS;
+
+	/* Set the maximum fan rpm */
+	ret = emc230x_write_fan_rpm_target(priv->i2c_client, channel, max_rpm);
+	if (ret)
+		return ret;
+
+	/* Enable RPM closed-loop control */
+	ret = emc230x_enable_rpm_control(dev, priv->i2c_client, channel, true);
+	if (ret)
+		return ret;
+
+	snprintf(faninfo->name, MAX_COOLING_DEV_NAME_LEN, "%pOFn%d", child, channel);
+
+	faninfo->tcdev = devm_thermal_of_cooling_device_register(dev, child,
+								 faninfo->name,
+								 faninfo,
+								 &emc230x_fan_cooling_ops);
+	dev_info(dev,
+		 "channel %d registered as cooling device %d, min/max RPM %d/%d step %d\n",
+		 channel, faninfo->tcdev->id, min_rpm, max_rpm, faninfo->cooling_step);
+
+	return 0;
+}
+
+static const struct hwmon_ops emc230x_hwmon_ops = {
+	.is_visible = emc230x_hwmon_is_visible,
+	.read = emc230x_hwmon_read,
+	.write = emc230x_hwmon_write,
+};
+
+static const struct hwmon_chip_info emc230x_chip_info = {
+	.ops = &emc230x_hwmon_ops,
+	.info = emc2301_hwmon_info
+};
+
+static int emc230x_probe(struct i2c_client *i2c)
+{
+	struct device *dev = &i2c->dev;
+	struct device *hwmon_dev;
+	struct device_node *np, *child;
+	struct emc230x_data *priv;
+	const struct i2c_device_id *dev_id;
+	int ret;
+
+	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	priv = devm_kzalloc(dev, sizeof(struct emc230x_data), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->i2c_client = i2c;
+
+	dev_id = i2c_match_id(emc230x_ids, i2c);
+	if (!dev_id)
+		return -ENODEV;
+
+	priv->device_max_channels = (u32)dev_id->driver_data;
+
+	if (IS_REACHABLE(CONFIG_THERMAL) && dev->of_node) {
+		np = dev->of_node;
+		for_each_child_of_node(np, child) {
+			ret = emc230x_create_fan(dev, child, priv);
+			if (ret)
+				of_node_put(child);
+		}
+	}
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, i2c->name,
+							 priv,
+							 &emc230x_chip_info,
+							 NULL);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct i2c_driver emc230x_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name = "emc230x",
+	},
+	.probe_new = emc230x_probe,
+	.id_table = emc230x_ids,
+};
+
+module_i2c_driver(emc230x_driver);
+
+MODULE_AUTHOR("Mathew McBride <matt@traverse.com.au>");
+MODULE_DESCRIPTION("Microchip EMC230X family PWM RPM fan controller driver");
+MODULE_LICENSE("GPL");
