drivers/hwmon/max8688.c

   1 /*
   2  * Hardware monitoring driver for Maxim MAX8688
   3  *
   4  * Copyright (c) 2011 Ericsson AB.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/err.h>
  25 #include <linux/i2c.h>
  26 #include "pmbus.h"
  27
  28 #define MAX8688_MFG_STATUS              0xd8
  29
  30 #define MAX8688_STATUS_OC_FAULT         (1 << 4)
  31 #define MAX8688_STATUS_OV_FAULT         (1 << 5)
  32 #define MAX8688_STATUS_OV_WARNING       (1 << 8)
  33 #define MAX8688_STATUS_UV_FAULT         (1 << 9)
  34 #define MAX8688_STATUS_UV_WARNING       (1 << 10)
  35 #define MAX8688_STATUS_UC_FAULT         (1 << 11)
  36 #define MAX8688_STATUS_OC_WARNING       (1 << 12)
  37 #define MAX8688_STATUS_OT_FAULT         (1 << 13)
  38 #define MAX8688_STATUS_OT_WARNING       (1 << 14)
  39
  40 static int max8688_read_byte_data(struct i2c_client *client, int page, int reg)
  41 {
  42         int ret = 0;
  43         int mfg_status;
  44
  45         if (page)
  46                 return -EINVAL;
  47
  48         switch (reg) {
  49         case PMBUS_STATUS_VOUT:
  50                 mfg_status = pmbus_read_word_data(client, 0,
  51                                                   MAX8688_MFG_STATUS);
  52                 if (mfg_status < 0)
  53                         return mfg_status;
  54                 if (mfg_status & MAX8688_STATUS_UV_WARNING)
  55                         ret |= PB_VOLTAGE_UV_WARNING;
  56                 if (mfg_status & MAX8688_STATUS_UV_FAULT)
  57                         ret |= PB_VOLTAGE_UV_FAULT;
  58                 if (mfg_status & MAX8688_STATUS_OV_WARNING)
  59                         ret |= PB_VOLTAGE_OV_WARNING;
  60                 if (mfg_status & MAX8688_STATUS_OV_FAULT)
  61                         ret |= PB_VOLTAGE_OV_FAULT;
  62                 break;
  63         case PMBUS_STATUS_IOUT:
  64                 mfg_status = pmbus_read_word_data(client, 0,
  65                                                   MAX8688_MFG_STATUS);
  66                 if (mfg_status < 0)
  67                         return mfg_status;
  68                 if (mfg_status & MAX8688_STATUS_UC_FAULT)
  69                         ret |= PB_IOUT_UC_FAULT;
  70                 if (mfg_status & MAX8688_STATUS_OC_WARNING)
  71                         ret |= PB_IOUT_OC_WARNING;
  72                 if (mfg_status & MAX8688_STATUS_OC_FAULT)
  73                         ret |= PB_IOUT_OC_FAULT;
  74                 break;
  75         case PMBUS_STATUS_TEMPERATURE:
  76                 mfg_status = pmbus_read_word_data(client, 0,
  77                                                   MAX8688_MFG_STATUS);
  78                 if (mfg_status < 0)
  79                         return mfg_status;
  80                 if (mfg_status & MAX8688_STATUS_OT_WARNING)
  81                         ret |= PB_TEMP_OT_WARNING;
  82                 if (mfg_status & MAX8688_STATUS_OT_FAULT)
  83                         ret |= PB_TEMP_OT_FAULT;
  84                 break;
  85         default:
  86                 ret = -ENODATA;
  87                 break;
  88         }
  89         return ret;
  90 }
  91
  92 static struct pmbus_driver_info max8688_info = {
  93         .pages = 1,
  94         .direct[PSC_VOLTAGE_IN] = true,
  95         .direct[PSC_VOLTAGE_OUT] = true,
  96         .direct[PSC_TEMPERATURE] = true,
  97         .direct[PSC_CURRENT_OUT] = true,
  98         .m[PSC_VOLTAGE_IN] = 19995,
  99         .b[PSC_VOLTAGE_IN] = 0,
 100         .R[PSC_VOLTAGE_IN] = -1,
 101         .m[PSC_VOLTAGE_OUT] = 19995,
 102         .b[PSC_VOLTAGE_OUT] = 0,
 103         .R[PSC_VOLTAGE_OUT] = -1,
 104         .m[PSC_CURRENT_OUT] = 23109,
 105         .b[PSC_CURRENT_OUT] = 0,
 106         .R[PSC_CURRENT_OUT] = -2,
 107         .m[PSC_TEMPERATURE] = -7612,
 108         .b[PSC_TEMPERATURE] = 335,
 109         .R[PSC_TEMPERATURE] = -3,
 110         .func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP
 111                 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
 112                 | PMBUS_HAVE_STATUS_TEMP,
 113         .read_byte_data = max8688_read_byte_data,
 114 };
 115
 116 static int max8688_probe(struct i2c_client *client,
 117                          const struct i2c_device_id *id)
 118 {
 119         return pmbus_do_probe(client, id, &max8688_info);
 120 }
 121
 122 static int max8688_remove(struct i2c_client *client)
 123 {
 124         return pmbus_do_remove(client);
 125 }
 126
 127 static const struct i2c_device_id max8688_id[] = {
 128         {"max8688", 0},
 129         { }
 130 };
 131
 132 MODULE_DEVICE_TABLE(i2c, max8688_id);
 133
 134 /* This is the driver that will be inserted */
 135 static struct i2c_driver max8688_driver = {
 136         .driver = {
 137                    .name = "max8688",
 138                    },
 139         .probe = max8688_probe,
 140         .remove = max8688_remove,
 141         .id_table = max8688_id,
 142 };
 143
 144 static int __init max8688_init(void)
 145 {
 146         return i2c_add_driver(&max8688_driver);
 147 }
 148
 149 static void __exit max8688_exit(void)
 150 {
 151         i2c_del_driver(&max8688_driver);
 152 }
 153
 154 MODULE_AUTHOR("Guenter Roeck");
 155 MODULE_DESCRIPTION("PMBus driver for Maxim MAX8688");
 156 MODULE_LICENSE("GPL");
 157 module_init(max8688_init);
 158 module_exit(max8688_exit);