drivers/hwmon/pmbus/isl68137.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Hardware monitoring driver for Intersil ISL68137
   4  *
   5  * Copyright (c) 2017 Google Inc
   6  *
   7  */
   8
   9 #include <linux/err.h>
  10 #include <linux/hwmon-sysfs.h>
  11 #include <linux/i2c.h>
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/string.h>
  16 #include <linux/sysfs.h>
  17 #include "pmbus.h"
  18
  19 #define ISL68137_VOUT_AVS       0x30
  20
  21 static ssize_t isl68137_avs_enable_show_page(struct i2c_client *client,
  22                                              int page,
  23                                              char *buf)
  24 {
  25         int val = pmbus_read_byte_data(client, page, PMBUS_OPERATION);
  26
  27         return sprintf(buf, "%d\n",
  28                        (val & ISL68137_VOUT_AVS) == ISL68137_VOUT_AVS ? 1 : 0);
  29 }
  30
  31 static ssize_t isl68137_avs_enable_store_page(struct i2c_client *client,
  32                                               int page,
  33                                               const char *buf, size_t count)
  34 {
  35         int rc, op_val;
  36         bool result;
  37
  38         rc = kstrtobool(buf, &result);
  39         if (rc)
  40                 return rc;
  41
  42         op_val = result ? ISL68137_VOUT_AVS : 0;
  43
  44         /*
  45          * Writes to VOUT setpoint over AVSBus will persist after the VRM is
  46          * switched to PMBus control. Switching back to AVSBus control
  47          * restores this persisted setpoint rather than re-initializing to
  48          * PMBus VOUT_COMMAND. Writing VOUT_COMMAND first over PMBus before
  49          * enabling AVS control is the workaround.
  50          */
  51         if (op_val == ISL68137_VOUT_AVS) {
  52                 rc = pmbus_read_word_data(client, page, PMBUS_VOUT_COMMAND);
  53                 if (rc < 0)
  54                         return rc;
  55
  56                 rc = pmbus_write_word_data(client, page, PMBUS_VOUT_COMMAND,
  57                                            rc);
  58                 if (rc < 0)
  59                         return rc;
  60         }
  61
  62         rc = pmbus_update_byte_data(client, page, PMBUS_OPERATION,
  63                                     ISL68137_VOUT_AVS, op_val);
  64
  65         return (rc < 0) ? rc : count;
  66 }
  67
  68 static ssize_t isl68137_avs_enable_show(struct device *dev,
  69                                         struct device_attribute *devattr,
  70                                         char *buf)
  71 {
  72         struct i2c_client *client = to_i2c_client(dev->parent);
  73         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  74
  75         return isl68137_avs_enable_show_page(client, attr->index, buf);
  76 }
  77
  78 static ssize_t isl68137_avs_enable_store(struct device *dev,
  79                                 struct device_attribute *devattr,
  80                                 const char *buf, size_t count)
  81 {
  82         struct i2c_client *client = to_i2c_client(dev->parent);
  83         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  84
  85         return isl68137_avs_enable_store_page(client, attr->index, buf, count);
  86 }
  87
  88 static SENSOR_DEVICE_ATTR_RW(avs0_enable, isl68137_avs_enable, 0);
  89 static SENSOR_DEVICE_ATTR_RW(avs1_enable, isl68137_avs_enable, 1);
  90
  91 static struct attribute *enable_attrs[] = {
  92         &sensor_dev_attr_avs0_enable.dev_attr.attr,
  93         &sensor_dev_attr_avs1_enable.dev_attr.attr,
  94         NULL,
  95 };
  96
  97 static const struct attribute_group enable_group = {
  98         .attrs = enable_attrs,
  99 };
 100
 101 static const struct attribute_group *attribute_groups[] = {
 102         &enable_group,
 103         NULL,
 104 };
 105
 106 static struct pmbus_driver_info isl68137_info = {
 107         .pages = 2,
 108         .format[PSC_VOLTAGE_IN] = direct,
 109         .format[PSC_VOLTAGE_OUT] = direct,
 110         .format[PSC_CURRENT_IN] = direct,
 111         .format[PSC_CURRENT_OUT] = direct,
 112         .format[PSC_POWER] = direct,
 113         .format[PSC_TEMPERATURE] = direct,
 114         .m[PSC_VOLTAGE_IN] = 1,
 115         .b[PSC_VOLTAGE_IN] = 0,
 116         .R[PSC_VOLTAGE_IN] = 3,
 117         .m[PSC_VOLTAGE_OUT] = 1,
 118         .b[PSC_VOLTAGE_OUT] = 0,
 119         .R[PSC_VOLTAGE_OUT] = 3,
 120         .m[PSC_CURRENT_IN] = 1,
 121         .b[PSC_CURRENT_IN] = 0,
 122         .R[PSC_CURRENT_IN] = 2,
 123         .m[PSC_CURRENT_OUT] = 1,
 124         .b[PSC_CURRENT_OUT] = 0,
 125         .R[PSC_CURRENT_OUT] = 1,
 126         .m[PSC_POWER] = 1,
 127         .b[PSC_POWER] = 0,
 128         .R[PSC_POWER] = 0,
 129         .m[PSC_TEMPERATURE] = 1,
 130         .b[PSC_TEMPERATURE] = 0,
 131         .R[PSC_TEMPERATURE] = 0,
 132         .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
 133             | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
 134             | PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_TEMP
 135             | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
 136             | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
 137         .func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
 138             | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
 139         .groups = attribute_groups,
 140 };
 141
 142 static int isl68137_probe(struct i2c_client *client,
 143                           const struct i2c_device_id *id)
 144 {
 145         return pmbus_do_probe(client, id, &isl68137_info);
 146 }
 147
 148 static const struct i2c_device_id isl68137_id[] = {
 149         {"isl68137", 0},
 150         {}
 151 };
 152
 153 MODULE_DEVICE_TABLE(i2c, isl68137_id);
 154
 155 /* This is the driver that will be inserted */
 156 static struct i2c_driver isl68137_driver = {
 157         .driver = {
 158                    .name = "isl68137",
 159                    },
 160         .probe = isl68137_probe,
 161         .remove = pmbus_do_remove,
 162         .id_table = isl68137_id,
 163 };
 164
 165 module_i2c_driver(isl68137_driver);
 166
 167 MODULE_AUTHOR("Maxim Sloyko <maxims@google.com>");
 168 MODULE_DESCRIPTION("PMBus driver for Intersil ISL68137");
 169 MODULE_LICENSE("GPL");