1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
/*
* (C) Copyright 2006
* Heiko Schocher, DENX Software Enginnering <hs@denx.de>
*
* based on dtt/lm75.c which is ...
*
* (C) Copyright 2001
* Bill Hunter, Wave 7 Optics, williamhunter@mediaone.net
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
/*
* On Semiconductor's LM81 Temperature Sensor
*/
#include <common.h>
#include <i2c.h>
#include <dtt.h>
/*
* Device code
*/
#define DTT_I2C_DEV_CODE 0x2c /* ON Semi's LM81 device */
#define DTT_READ_TEMP 0x27
#define DTT_CONFIG_TEMP 0x4b
#define DTT_TEMP_MAX 0x39
#define DTT_TEMP_HYST 0x3a
#define DTT_CONFIG 0x40
int dtt_read(int sensor, int reg)
{
int dlen = 1;
uchar data[2];
/*
* Calculate sensor address and register.
*/
sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */
/*
* Now try to read the register.
*/
if (i2c_read(sensor, reg, 1, data, dlen) != 0)
return -1;
return (int)data[0];
} /* dtt_read() */
int dtt_write(int sensor, int reg, int val)
{
uchar data;
/*
* Calculate sensor address and register.
*/
sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */
data = (char)(val & 0xff);
/*
* Write value to register.
*/
if (i2c_write(sensor, reg, 1, &data, 1) != 0)
return 1;
return 0;
} /* dtt_write() */
#define DTT_MANU 0x3e
#define DTT_REV 0x3f
#define DTT_CONFIG 0x40
#define DTT_ADR 0x48
static int _dtt_init(int sensor)
{
int man;
int adr;
int rev;
if (dtt_write (sensor, DTT_CONFIG, 0x01) < 0)
return 1;
/* The LM81 needs 400ms to get the correct values ... */
udelay (400000);
man = dtt_read (sensor, DTT_MANU);
if (man != 0x01)
return 1;
adr = dtt_read (sensor, DTT_ADR);
if (adr < 0)
return 1;
rev = dtt_read (sensor, DTT_REV);
if (adr < 0)
return 1;
printf ("DTT: Found LM81@%x Rev: %d\n", adr, rev);
return 0;
} /* _dtt_init() */
int dtt_init (void)
{
int i;
unsigned char sensors[] = CONFIG_DTT_SENSORS;
const char *const header = "DTT: ";
for (i = 0; i < sizeof(sensors); i++) {
if (_dtt_init(sensors[i]) != 0)
printf("%s%d FAILED INIT\n", header, i+1);
else
printf("%s%d is %i C\n", header, i+1,
dtt_get_temp(sensors[i]));
}
return (0);
} /* dtt_init() */
#define TEMP_FROM_REG(temp) \
((temp)<256?((((temp)&0x1fe) >> 1) * 10) + ((temp) & 1) * 5: \
((((temp)&0x1fe) >> 1) -255) * 10 - ((temp) & 1) * 5) \
int dtt_get_temp(int sensor)
{
int val = dtt_read (sensor, DTT_READ_TEMP);
int tmpcnf = dtt_read (sensor, DTT_CONFIG_TEMP);
return (TEMP_FROM_REG((val << 1) + ((tmpcnf & 0x80) >> 7))) / 10;
} /* dtt_get_temp() */
|
