diff --git a/MAINTAINERS b/MAINTAINERS
index 979195fbd05419df66ce96cbe6a7439be12e7e58..5a00307d67e340b3b65370bb1f62ca3215fb2faa 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5436,6 +5436,12 @@ W: https://linuxtv.org
T: git git://linuxtv.org/media_tree.git
F: drivers/media/platform/sti/delta
+DELTA AHE-50DC FAN CONTROL MODULE DRIVER
+M: Zev Weiss <zev@bewilderbeest.net>
+L: linux-hwmon@vger.kernel.org
+S: Maintained
+F: drivers/hwmon/pmbus/delta-ahe50dc-fan.c
+
DELTA DPS920AB PSU DRIVER
M: Robert Marko <robert.marko@sartura.hr>
L: linux-hwmon@vger.kernel.org
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index ffb609cee3a4a19f3e536f508efa1dc83d829969..0b1157b883aa0decdff821daa8076e03369cec97 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -66,6 +66,16 @@ config SENSORS_BPA_RS600
This driver can also be built as a module. If so, the module will
be called bpa-rs600.
+config SENSORS_DELTA_AHE50DC_FAN
+ tristate "Delta AHE-50DC fan control module"
+ help
+ If you say yes here you get hardware monitoring support for
+ the integrated fan control module of the Delta AHE-50DC
+ Open19 power shelf.
+
+ This driver can also be built as a module. If so, the module
+ will be called delta-ahe50dc-fan.
+
config SENSORS_FSP_3Y
tristate "FSP/3Y-Power power supplies"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 0ed4d596a948e01a8338e5654fab4e1f46c7844d..a56b2897288d258320ccbd5efad135a47d414749 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o
obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o
obj-$(CONFIG_SENSORS_BPA_RS600) += bpa-rs600.o
+obj-$(CONFIG_SENSORS_DELTA_AHE50DC_FAN) += delta-ahe50dc-fan.o
obj-$(CONFIG_SENSORS_FSP_3Y) += fsp-3y.o
obj-$(CONFIG_SENSORS_IBM_CFFPS) += ibm-cffps.o
obj-$(CONFIG_SENSORS_DPS920AB) += dps920ab.o
diff --git a/drivers/hwmon/pmbus/delta-ahe50dc-fan.c b/drivers/hwmon/pmbus/delta-ahe50dc-fan.c
new file mode 100644
index 0000000000000000000000000000000000000000..40dffd9c4cbfc09be0d1be76546b583fda6efd9e
--- /dev/null
+++ b/drivers/hwmon/pmbus/delta-ahe50dc-fan.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Delta AHE-50DC power shelf fan control module driver
+ *
+ * Copyright 2021 Zev Weiss <zev@bewilderbeest.net>
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+
+#include "pmbus.h"
+
+#define AHE50DC_PMBUS_READ_TEMP4 0xd0
+
+static int ahe50dc_fan_read_word_data(struct i2c_client *client, int page, int phase, int reg)
+{
+ /* temp1 in (virtual) page 1 is remapped to mfr-specific temp4 */
+ if (page == 1) {
+ if (reg == PMBUS_READ_TEMPERATURE_1)
+ return i2c_smbus_read_word_data(client, AHE50DC_PMBUS_READ_TEMP4);
+ return -EOPNOTSUPP;
+ }
+
+ /*
+ * There's a fairly limited set of commands this device actually
+ * supports, so here we block attempts to read anything else (which
+ * return 0xffff and would cause confusion elsewhere).
+ */
+ switch (reg) {
+ case PMBUS_STATUS_WORD:
+ case PMBUS_FAN_COMMAND_1:
+ case PMBUS_FAN_COMMAND_2:
+ case PMBUS_FAN_COMMAND_3:
+ case PMBUS_FAN_COMMAND_4:
+ case PMBUS_STATUS_FAN_12:
+ case PMBUS_STATUS_FAN_34:
+ case PMBUS_READ_VIN:
+ case PMBUS_READ_TEMPERATURE_1:
+ case PMBUS_READ_TEMPERATURE_2:
+ case PMBUS_READ_TEMPERATURE_3:
+ case PMBUS_READ_FAN_SPEED_1:
+ case PMBUS_READ_FAN_SPEED_2:
+ case PMBUS_READ_FAN_SPEED_3:
+ case PMBUS_READ_FAN_SPEED_4:
+ return -ENODATA;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static struct pmbus_driver_info ahe50dc_fan_info = {
+ .pages = 2,
+ .format[PSC_FAN] = direct,
+ .format[PSC_TEMPERATURE] = direct,
+ .format[PSC_VOLTAGE_IN] = direct,
+ .m[PSC_FAN] = 1,
+ .b[PSC_FAN] = 0,
+ .R[PSC_FAN] = 0,
+ .m[PSC_TEMPERATURE] = 1,
+ .b[PSC_TEMPERATURE] = 0,
+ .R[PSC_TEMPERATURE] = 1,
+ .m[PSC_VOLTAGE_IN] = 1,
+ .b[PSC_VOLTAGE_IN] = 0,
+ .R[PSC_VOLTAGE_IN] = 3,
+ .func[0] = PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
+ PMBUS_HAVE_VIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_FAN34 |
+ PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_STATUS_FAN34 | PMBUS_PAGE_VIRTUAL,
+ .func[1] = PMBUS_HAVE_TEMP | PMBUS_PAGE_VIRTUAL,
+ .read_word_data = ahe50dc_fan_read_word_data,
+};
+
+/*
+ * CAPABILITY returns 0xff, which appears to be this device's way indicating
+ * it doesn't support something (and if we enable I2C_CLIENT_PEC on seeing bit
+ * 7 being set it generates bad PECs, so let's not go there).
+ */
+static struct pmbus_platform_data ahe50dc_fan_data = {
+ .flags = PMBUS_NO_CAPABILITY,
+};
+
+static int ahe50dc_fan_probe(struct i2c_client *client)
+{
+ client->dev.platform_data = &ahe50dc_fan_data;
+ return pmbus_do_probe(client, &ahe50dc_fan_info);
+}
+
+static const struct i2c_device_id ahe50dc_fan_id[] = {
+ { "ahe50dc_fan" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ahe50dc_fan_id);
+
+static const struct of_device_id __maybe_unused ahe50dc_fan_of_match[] = {
+ { .compatible = "delta,ahe50dc-fan" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ahe50dc_fan_of_match);
+
+static struct i2c_driver ahe50dc_fan_driver = {
+ .driver = {
+ .name = "ahe50dc_fan",
+ .of_match_table = of_match_ptr(ahe50dc_fan_of_match),
+ },
+ .probe_new = ahe50dc_fan_probe,
+ .id_table = ahe50dc_fan_id,
+};
+module_i2c_driver(ahe50dc_fan_driver);
+
+MODULE_AUTHOR("Zev Weiss <zev@bewilderbeest.net>");
+MODULE_DESCRIPTION("Driver for Delta AHE-50DC power shelf fan control module");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);