drivers/hwmon/pmbus/dps920ab.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Driver for Delta DPS920AB PSU
   4  *
   5  * Copyright (C) 2021 Delta Networks, Inc.
   6  * Copyright (C) 2021 Sartura Ltd.
   7  */
   8
   9 #include <linux/debugfs.h>
  10 #include <linux/i2c.h>
  11 #include <linux/module.h>
  12 #include <linux/of_device.h>
  13 #include "pmbus.h"
  14
  15 struct dps920ab_data {
  16         char *mfr_model;
  17         char *mfr_id;
  18 };
  19
  20 static int dps920ab_read_word_data(struct i2c_client *client, int page, int phase, int reg)
  21 {
  22         /*
  23          * This masks commands which are not supported.
  24          * PSU advertises that all features are supported,
  25          * in reality that unfortunately is not true.
  26          * So enable only those that the datasheet confirms.
  27          */
  28         switch (reg) {
  29         case PMBUS_FAN_COMMAND_1:
  30         case PMBUS_IOUT_OC_WARN_LIMIT:
  31         case PMBUS_STATUS_WORD:
  32         case PMBUS_READ_VIN:
  33         case PMBUS_READ_IIN:
  34         case PMBUS_READ_VOUT:
  35         case PMBUS_READ_IOUT:
  36         case PMBUS_READ_TEMPERATURE_1:
  37         case PMBUS_READ_TEMPERATURE_2:
  38         case PMBUS_READ_TEMPERATURE_3:
  39         case PMBUS_READ_FAN_SPEED_1:
  40         case PMBUS_READ_POUT:
  41         case PMBUS_READ_PIN:
  42         case PMBUS_MFR_VOUT_MIN:
  43         case PMBUS_MFR_VOUT_MAX:
  44         case PMBUS_MFR_IOUT_MAX:
  45         case PMBUS_MFR_POUT_MAX:
  46                 return pmbus_read_word_data(client, page, phase, reg);
  47         default:
  48                 return -ENXIO;
  49         }
  50 }
  51
  52 static int dps920ab_write_word_data(struct i2c_client *client, int page, int reg,
  53                                     u16 word)
  54 {
  55         /*
  56          * This masks commands which are not supported.
  57          * PSU only has one R/W register and that is
  58          * for the fan.
  59          */
  60         switch (reg) {
  61         case PMBUS_FAN_COMMAND_1:
  62                 return pmbus_write_word_data(client, page, reg, word);
  63         default:
  64                 return -EACCES;
  65         }
  66 }
  67
  68 static struct pmbus_driver_info dps920ab_info = {
  69         .pages = 1,
  70
  71         .format[PSC_VOLTAGE_IN] = linear,
  72         .format[PSC_VOLTAGE_OUT] = linear,
  73         .format[PSC_CURRENT_IN] = linear,
  74         .format[PSC_CURRENT_OUT] = linear,
  75         .format[PSC_POWER] = linear,
  76         .format[PSC_FAN] = linear,
  77         .format[PSC_TEMPERATURE] = linear,
  78
  79         .func[0] =
  80                 PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
  81                 PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT |
  82                 PMBUS_HAVE_TEMP  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
  83                 PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 |
  84                 PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
  85                 PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
  86         .read_word_data = dps920ab_read_word_data,
  87         .write_word_data = dps920ab_write_word_data,
  88 };
  89
  90 static int dps920ab_mfr_id_show(struct seq_file *s, void *data)
  91 {
  92         struct dps920ab_data *priv = s->private;
  93
  94         seq_printf(s, "%s\n", priv->mfr_id);
  95
  96         return 0;
  97 }
  98
  99 DEFINE_SHOW_ATTRIBUTE(dps920ab_mfr_id);
 100
 101 static int dps920ab_mfr_model_show(struct seq_file *s, void *data)
 102 {
 103         struct dps920ab_data *priv = s->private;
 104
 105         seq_printf(s, "%s\n", priv->mfr_model);
 106
 107         return 0;
 108 }
 109
 110 DEFINE_SHOW_ATTRIBUTE(dps920ab_mfr_model);
 111
 112 static void dps920ab_init_debugfs(struct dps920ab_data *data, struct i2c_client *client)
 113 {
 114         struct dentry *debugfs_dir;
 115         struct dentry *root;
 116
 117         root = pmbus_get_debugfs_dir(client);
 118         if (!root)
 119                 return;
 120
 121         debugfs_dir = debugfs_create_dir(client->name, root);
 122
 123         debugfs_create_file("mfr_id",
 124                             0400,
 125                             debugfs_dir,
 126                             data,
 127                             &dps920ab_mfr_id_fops);
 128
 129         debugfs_create_file("mfr_model",
 130                             0400,
 131                             debugfs_dir,
 132                             data,
 133                             &dps920ab_mfr_model_fops);
 134 }
 135
 136 static int dps920ab_probe(struct i2c_client *client)
 137 {
 138         u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
 139         struct dps920ab_data *data;
 140         int ret;
 141
 142         data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
 143         if (!data)
 144                 return -ENOMEM;
 145
 146         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
 147         if (ret < 0) {
 148                 dev_err(&client->dev, "Failed to read Manufacturer ID\n");
 149                 return ret;
 150         }
 151
 152         buf[ret] = '\0';
 153         if (ret != 5 || strncmp(buf, "DELTA", 5)) {
 154                 buf[ret] = '\0';
 155                 dev_err(&client->dev, "Unsupported Manufacturer ID '%s'\n", buf);
 156                 return -ENODEV;
 157         }
 158         data->mfr_id = devm_kstrdup(&client->dev, buf, GFP_KERNEL);
 159         if (!data->mfr_id)
 160                 return -ENOMEM;
 161
 162         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
 163         if (ret < 0) {
 164                 dev_err(&client->dev, "Failed to read Manufacturer Model\n");
 165                 return ret;
 166         }
 167
 168         buf[ret] = '\0';
 169         if (ret != 11 || strncmp(buf, "DPS-920AB", 9)) {
 170                 dev_err(&client->dev, "Unsupported Manufacturer Model '%s'\n", buf);
 171                 return -ENODEV;
 172         }
 173         data->mfr_model = devm_kstrdup(&client->dev, buf, GFP_KERNEL);
 174         if (!data->mfr_model)
 175                 return -ENOMEM;
 176
 177         ret = pmbus_do_probe(client, &dps920ab_info);
 178         if (ret)
 179                 return ret;
 180
 181         dps920ab_init_debugfs(data, client);
 182
 183         return 0;
 184 }
 185
 186 static const struct of_device_id __maybe_unused dps920ab_of_match[] = {
 187         { .compatible = "delta,dps920ab", },
 188         {}
 189 };
 190
 191 MODULE_DEVICE_TABLE(of, dps920ab_of_match);
 192
 193 static struct i2c_driver dps920ab_driver = {
 194         .driver = {
 195                    .name = "dps920ab",
 196                    .of_match_table = of_match_ptr(dps920ab_of_match),
 197         },
 198         .probe_new = dps920ab_probe,
 199 };
 200
 201 module_i2c_driver(dps920ab_driver);
 202
 203 MODULE_AUTHOR("Robert Marko <[email protected]>");
 204 MODULE_DESCRIPTION("PMBus driver for Delta DPS920AB PSU");
 205 MODULE_LICENSE("GPL");
 206 MODULE_IMPORT_NS(PMBUS);