--- /dev/null
+Kernel driver isl68137
+======================
+
+Supported chips:
+ * Intersil ISL68137
+ Prefix: 'isl68137'
+ Addresses scanned: -
+ Datasheet: Publicly available at the Intersil website
+ https://www.intersil.com/content/dam/Intersil/documents/isl6/isl68137.pdf
+
+Authors:
+ Maxim Sloyko <maxims@google.com>
+ Robert Lippert <rlippert@google.com>
+ Patrick Venture <venture@google.com>
+
+Description
+-----------
+
+Intersil ISL68137 is a digital output 7-phase configurable PWM
+controller with an AVSBus interface.
+
+Usage Notes
+-----------
+
+This driver does not probe for PMBus devices. You will have to instantiate
+devices explicitly.
+
+The ISL68137 AVS operation mode must be enabled/disabled at runtime.
+
+Beyond the normal sysfs pmbus attributes, the driver exposes a control attribute.
+
+Additional Sysfs attributes
+---------------------------
+
+avs(0|1)_enable Controls the AVS state of each rail.
+
+curr1_label "iin"
+curr1_input Measured input current
+curr1_crit Critical maximum current
+curr1_crit_alarm Current critical high alarm
+
+curr[2-3]_label "iout[1-2]"
+curr[2-3]_input Measured output current
+curr[2-3]_crit Critical maximum current
+curr[2-3]_crit_alarm Current critical high alarm
+
+in1_label "vin"
+in1_input Measured input voltage
+in1_lcrit Critical minimum input voltage
+in1_lcrit_alarm Input voltage critical low alarm
+in1_crit Critical maximum input voltage
+in1_crit_alarm Input voltage critical high alarm
+
+in[2-3]_label "vout[1-2]"
+in[2-3]_input Measured output voltage
+in[2-3]_lcrit Critical minimum output voltage
+in[2-3]_lcrit_alarm Output voltage critical low alarm
+in[2-3]_crit Critical maximum output voltage
+in[2-3]_crit_alarm Output voltage critical high alarm
+
+power1_label "pin"
+power1_input Measured input power
+power1_alarm Input power high alarm
+
+power[2-3]_label "pout[1-2]"
+power[2-3]_input Measured output power
+
+temp[1-3]_input Measured temperature
+temp[1-3]_crit Critical high temperature
+temp[1-3]_crit_alarm Chip temperature critical high alarm
+temp[1-3]_max Maximum temperature
+temp[1-3]_max_alarm Chip temperature high alarm
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for Intersil ISL68137
+ *
+ * Copyright (c) 2017 Google Inc
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include "pmbus.h"
+
+#define ISL68137_VOUT_AVS 0x30
+
+static ssize_t isl68137_avs_enable_show_page(struct i2c_client *client,
+ int page,
+ char *buf)
+{
+ int val = pmbus_read_byte_data(client, page, PMBUS_OPERATION);
+
+ return sprintf(buf, "%d\n",
+ (val & ISL68137_VOUT_AVS) == ISL68137_VOUT_AVS ? 1 : 0);
+}
+
+static ssize_t isl68137_avs_enable_store_page(struct i2c_client *client,
+ int page,
+ const char *buf, size_t count)
+{
+ int rc, op_val;
+ bool result;
+
+ rc = kstrtobool(buf, &result);
+ if (rc)
+ return rc;
+
+ op_val = result ? ISL68137_VOUT_AVS : 0;
+
+ /*
+ * Writes to VOUT setpoint over AVSBus will persist after the VRM is
+ * switched to PMBus control. Switching back to AVSBus control
+ * restores this persisted setpoint rather than re-initializing to
+ * PMBus VOUT_COMMAND. Writing VOUT_COMMAND first over PMBus before
+ * enabling AVS control is the workaround.
+ */
+ if (op_val == ISL68137_VOUT_AVS) {
+ rc = pmbus_read_word_data(client, page, PMBUS_VOUT_COMMAND);
+ if (rc < 0)
+ return rc;
+
+ rc = pmbus_write_word_data(client, page, PMBUS_VOUT_COMMAND,
+ rc);
+ if (rc < 0)
+ return rc;
+ }
+
+ rc = pmbus_update_byte_data(client, page, PMBUS_OPERATION,
+ ISL68137_VOUT_AVS, op_val);
+
+ return (rc < 0) ? rc : count;
+}
+
+static ssize_t isl68137_avs_enable_show(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev->parent);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return isl68137_avs_enable_show_page(client, attr->index, buf);
+}
+
+static ssize_t isl68137_avs_enable_store(struct device *dev,
+ struct device_attribute *devattr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev->parent);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+
+ return isl68137_avs_enable_store_page(client, attr->index, buf, count);
+}
+
+static SENSOR_DEVICE_ATTR_RW(avs0_enable, isl68137_avs_enable, 0);
+static SENSOR_DEVICE_ATTR_RW(avs1_enable, isl68137_avs_enable, 1);
+
+static struct attribute *enable_attrs[] = {
+ &sensor_dev_attr_avs0_enable.dev_attr.attr,
+ &sensor_dev_attr_avs1_enable.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group enable_group = {
+ .attrs = enable_attrs,
+};
+
+static const struct attribute_group *attribute_groups[] = {
+ &enable_group,
+ NULL,
+};
+
+static struct pmbus_driver_info isl68137_info = {
+ .pages = 2,
+ .format[PSC_VOLTAGE_IN] = direct,
+ .format[PSC_VOLTAGE_OUT] = direct,
+ .format[PSC_CURRENT_IN] = direct,
+ .format[PSC_CURRENT_OUT] = direct,
+ .format[PSC_POWER] = direct,
+ .format[PSC_TEMPERATURE] = direct,
+ .m[PSC_VOLTAGE_IN] = 1,
+ .b[PSC_VOLTAGE_IN] = 0,
+ .R[PSC_VOLTAGE_IN] = 3,
+ .m[PSC_VOLTAGE_OUT] = 1,
+ .b[PSC_VOLTAGE_OUT] = 0,
+ .R[PSC_VOLTAGE_OUT] = 3,
+ .m[PSC_CURRENT_IN] = 1,
+ .b[PSC_CURRENT_IN] = 0,
+ .R[PSC_CURRENT_IN] = 2,
+ .m[PSC_CURRENT_OUT] = 1,
+ .b[PSC_CURRENT_OUT] = 0,
+ .R[PSC_CURRENT_OUT] = 1,
+ .m[PSC_POWER] = 1,
+ .b[PSC_POWER] = 0,
+ .R[PSC_POWER] = 0,
+ .m[PSC_TEMPERATURE] = 1,
+ .b[PSC_TEMPERATURE] = 0,
+ .R[PSC_TEMPERATURE] = 0,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
+ | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
+ | PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_TEMP
+ | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
+ | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
+ .func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
+ | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
+ .groups = attribute_groups,
+};
+
+static int isl68137_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ return pmbus_do_probe(client, id, &isl68137_info);
+}
+
+static const struct i2c_device_id isl68137_id[] = {
+ {"isl68137", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, isl68137_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver isl68137_driver = {
+ .driver = {
+ .name = "isl68137",
+ },
+ .probe = isl68137_probe,
+ .remove = pmbus_do_remove,
+ .id_table = isl68137_id,
+};
+
+module_i2c_driver(isl68137_driver);
+
+MODULE_AUTHOR("Maxim Sloyko <maxims@google.com>");
+MODULE_DESCRIPTION("PMBus driver for Intersil ISL68137");
+MODULE_LICENSE("GPL");