drivers/hwmon/pmbus/ir35221.c

   1 /*
   2  * Hardware monitoring driver for IR35221
   3  *
   4  * Copyright (C) IBM Corporation 2017.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/err.h>
  13 #include <linux/i2c.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include "pmbus.h"
  18
  19 #define IR35221_MFR_VIN_PEAK            0xc5
  20 #define IR35221_MFR_VOUT_PEAK           0xc6
  21 #define IR35221_MFR_IOUT_PEAK           0xc7
  22 #define IR35221_MFR_TEMP_PEAK           0xc8
  23 #define IR35221_MFR_VIN_VALLEY          0xc9
  24 #define IR35221_MFR_VOUT_VALLEY         0xca
  25 #define IR35221_MFR_IOUT_VALLEY         0xcb
  26 #define IR35221_MFR_TEMP_VALLEY         0xcc
  27
  28 static int ir35221_read_word_data(struct i2c_client *client, int page, int reg)
  29 {
  30         int ret;
  31
  32         switch (reg) {
  33         case PMBUS_VIRT_READ_VIN_MAX:
  34                 ret = pmbus_read_word_data(client, page, IR35221_MFR_VIN_PEAK);
  35                 break;
  36         case PMBUS_VIRT_READ_VOUT_MAX:
  37                 ret = pmbus_read_word_data(client, page, IR35221_MFR_VOUT_PEAK);
  38                 break;
  39         case PMBUS_VIRT_READ_IOUT_MAX:
  40                 ret = pmbus_read_word_data(client, page, IR35221_MFR_IOUT_PEAK);
  41                 break;
  42         case PMBUS_VIRT_READ_TEMP_MAX:
  43                 ret = pmbus_read_word_data(client, page, IR35221_MFR_TEMP_PEAK);
  44                 break;
  45         case PMBUS_VIRT_READ_VIN_MIN:
  46                 ret = pmbus_read_word_data(client, page,
  47                                            IR35221_MFR_VIN_VALLEY);
  48                 break;
  49         case PMBUS_VIRT_READ_VOUT_MIN:
  50                 ret = pmbus_read_word_data(client, page,
  51                                            IR35221_MFR_VOUT_VALLEY);
  52                 break;
  53         case PMBUS_VIRT_READ_IOUT_MIN:
  54                 ret = pmbus_read_word_data(client, page,
  55                                            IR35221_MFR_IOUT_VALLEY);
  56                 break;
  57         case PMBUS_VIRT_READ_TEMP_MIN:
  58                 ret = pmbus_read_word_data(client, page,
  59                                            IR35221_MFR_TEMP_VALLEY);
  60                 break;
  61         default:
  62                 ret = -ENODATA;
  63                 break;
  64         }
  65
  66         return ret;
  67 }
  68
  69 static int ir35221_probe(struct i2c_client *client,
  70                          const struct i2c_device_id *id)
  71 {
  72         struct pmbus_driver_info *info;
  73         u8 buf[I2C_SMBUS_BLOCK_MAX];
  74         int ret;
  75
  76         if (!i2c_check_functionality(client->adapter,
  77                                      I2C_FUNC_SMBUS_READ_BYTE_DATA
  78                                 | I2C_FUNC_SMBUS_READ_WORD_DATA
  79                                 | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
  80                 return -ENODEV;
  81
  82         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
  83         if (ret < 0) {
  84                 dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
  85                 return ret;
  86         }
  87         if (ret != 2 || strncmp(buf, "RI", strlen("RI"))) {
  88                 dev_err(&client->dev, "MFR_ID unrecognised\n");
  89                 return -ENODEV;
  90         }
  91
  92         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
  93         if (ret < 0) {
  94                 dev_err(&client->dev, "Failed to read PMBUS_MFR_MODEL\n");
  95                 return ret;
  96         }
  97         if (ret != 2 || !(buf[0] == 0x6c && buf[1] == 0x00)) {
  98                 dev_err(&client->dev, "MFR_MODEL unrecognised\n");
  99                 return -ENODEV;
 100         }
 101
 102         info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
 103                             GFP_KERNEL);
 104         if (!info)
 105                 return -ENOMEM;
 106
 107         info->read_word_data = ir35221_read_word_data;
 108
 109         info->pages = 2;
 110         info->format[PSC_VOLTAGE_IN] = linear;
 111         info->format[PSC_VOLTAGE_OUT] = linear;
 112         info->format[PSC_CURRENT_IN] = linear;
 113         info->format[PSC_CURRENT_OUT] = linear;
 114         info->format[PSC_POWER] = linear;
 115         info->format[PSC_TEMPERATURE] = linear;
 116
 117         info->func[0] = PMBUS_HAVE_VIN
 118                 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
 119                 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
 120                 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
 121                 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
 122                 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP;
 123         info->func[1] = info->func[0];
 124
 125         return pmbus_do_probe(client, id, info);
 126 }
 127
 128 static const struct i2c_device_id ir35221_id[] = {
 129         {"ir35221", 0},
 130         {}
 131 };
 132
 133 MODULE_DEVICE_TABLE(i2c, ir35221_id);
 134
 135 static struct i2c_driver ir35221_driver = {
 136         .driver = {
 137                 .name   = "ir35221",
 138         },
 139         .probe          = ir35221_probe,
 140         .remove         = pmbus_do_remove,
 141         .id_table       = ir35221_id,
 142 };
 143
 144 module_i2c_driver(ir35221_driver);
 145
 146 MODULE_AUTHOR("Samuel Mendoza-Jonas <sam@mendozajonas.com");
 147 MODULE_DESCRIPTION("PMBus driver for IR35221");
 148 MODULE_LICENSE("GPL");