drivers/hwmon/adm1021.c

   1 /*
   2  * (C) Copyright 2003
   3  * Murray Jensen, CSIRO-MIT, Murray.Jensen@csiro.au
   4  *
   5  * based on dtt/lm75.c which is ...
   6  *
   7  * (C) Copyright 2001
   8  * Bill Hunter,  Wave 7 Optics, williamhunter@mediaone.net
   9  *
  10  * See file CREDITS for list of people who contributed to this
  11  * project.
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License as
  15  * published by the Free Software Foundation; either version 2 of
  16  * the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  26  * MA 02111-1307 USA
  27  */
  28
  29 /*
  30  * Analog Devices's ADM1021
  31  * "Low Cost Microprocessor System Temperature Monitor"
  32  */
  33
  34 #include <common.h>
  35
  36 #ifdef CONFIG_DTT_ADM1021
  37
  38 #include <i2c.h>
  39 #include <dtt.h>
  40
  41 typedef
  42         struct {
  43                 uint i2c_addr:7;        /* 7bit i2c chip address */
  44                 uint conv_rate:3;       /* conversion rate */
  45                 uint enable_alert:1;    /* enable alert output pin */
  46                 uint enable_local:1;    /* enable internal temp sensor */
  47                 uint max_local:8;       /* internal temp maximum */
  48                 uint min_local:8;       /* internal temp minimum */
  49                 uint enable_remote:1;   /* enable remote temp sensor */
  50                 uint max_remote:8;      /* remote temp maximum */
  51                 uint min_remote:8;      /* remote temp minimum */
  52         }
  53 dtt_cfg_t;
  54
  55 dtt_cfg_t dttcfg[] = CFG_DTT_ADM1021;
  56
  57 int
  58 dtt_read (int sensor, int reg)
  59 {
  60         dtt_cfg_t *dcp = &dttcfg[sensor >> 1];
  61         uchar data;
  62
  63         if (i2c_read(dcp->i2c_addr, reg, 1, &data, 1) != 0)
  64                 return -1;
  65
  66         return (int)data;
  67 } /* dtt_read() */
  68
  69 int
  70 dtt_write (int sensor, int reg, int val)
  71 {
  72         dtt_cfg_t *dcp = &dttcfg[sensor >> 1];
  73         uchar data;
  74
  75         data = (uchar)(val & 0xff);
  76
  77         if (i2c_write(dcp->i2c_addr, reg, 1, &data, 1) != 0)
  78                 return 1;
  79
  80         return 0;
  81 } /* dtt_write() */
  82
  83 static int
  84 _dtt_init (int sensor)
  85 {
  86         dtt_cfg_t *dcp = &dttcfg[sensor >> 1];
  87         int reg, val;
  88
  89         if (((sensor & 1) == 0 ? dcp->enable_local : dcp->enable_remote) == 0)
  90                 return 1;       /* sensor is disabled (or rather ignored) */
  91
  92         /*
  93          * Setup High Limit register
  94          */
  95         if ((sensor & 1) == 0) {
  96                 reg = DTT_WRITE_LOC_HIGHLIM;
  97                 val = dcp->max_local;
  98         }
  99         else {
 100                 reg = DTT_WRITE_REM_HIGHLIM;
 101                 val = dcp->max_remote;
 102         }
 103         if (dtt_write (sensor, reg, val) != 0)
 104                 return 1;
 105
 106         /*
 107          * Setup Low Limit register
 108          */
 109         if ((sensor & 1) == 0) {
 110                 reg = DTT_WRITE_LOC_LOWLIM;
 111                 val = dcp->min_local;
 112         }
 113         else {
 114                 reg = DTT_WRITE_REM_LOWLIM;
 115                 val = dcp->min_remote;
 116         }
 117         if (dtt_write (sensor, reg, val) != 0)
 118                 return 1;
 119
 120         /* shouldn't hurt if the rest gets done twice */
 121
 122         /*
 123          * Setup Conversion Rate register
 124          */
 125         if (dtt_write (sensor, DTT_WRITE_CONVRATE, dcp->conv_rate) != 0)
 126                 return 1;
 127
 128         /*
 129          * Setup configuraton register
 130          */
 131         val = 0;                                /* running */
 132         if (dcp->enable_alert == 0)
 133                 val |= DTT_CONFIG_ALERT_MASKED; /* mask ALERT pin */
 134         if (dtt_write (sensor, DTT_WRITE_CONFIG, val) != 0)
 135                 return 1;
 136
 137         return 0;
 138 } /* _dtt_init() */
 139
 140 int
 141 dtt_init (void)
 142 {
 143         int i;
 144         unsigned char sensors[] = CONFIG_DTT_SENSORS;
 145         const char *const header = "DTT:   ";
 146
 147         /* switch to correct I2C bus */
 148         I2C_SET_BUS(CFG_DTT_BUS_NUM);
 149
 150         for (i = 0; i < sizeof(sensors); i++) {
 151                 if (_dtt_init(sensors[i]) != 0)
 152                         printf ("%s%d FAILED INIT\n", header, i+1);
 153                 else
 154                         printf ("%s%d is %i C\n", header, i+1,
 155                                 dtt_get_temp(sensors[i]));
 156         }
 157
 158         return (0);
 159 } /* dtt_init() */
 160
 161 int
 162 dtt_get_temp (int sensor)
 163 {
 164         signed char val;
 165
 166         if ((sensor & 1) == 0)
 167                 val = dtt_read(sensor, DTT_READ_LOC_VALUE);
 168         else
 169                 val = dtt_read(sensor, DTT_READ_REM_VALUE);
 170
 171         return (int) val;
 172 } /* dtt_get_temp() */
 173
 174 #endif /* CONFIG_DTT_ADM1021 */