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6dedf3d4 HS |
1 | /* |
2 | * (C) Copyright 2006 | |
3 | * Heiko Schocher, DENX Software Enginnering <hs@denx.de> | |
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 | * On Semiconductor's LM81 Temperature Sensor | |
31 | */ | |
32 | ||
33 | #include <common.h> | |
6dedf3d4 HS |
34 | #include <i2c.h> |
35 | #include <dtt.h> | |
36 | ||
37 | /* | |
38 | * Device code | |
39 | */ | |
40 | #define DTT_I2C_DEV_CODE 0x2c /* ON Semi's LM81 device */ | |
6ecbb45b MS |
41 | #define DTT_READ_TEMP 0x27 |
42 | #define DTT_CONFIG_TEMP 0x4b | |
43 | #define DTT_TEMP_MAX 0x39 | |
44 | #define DTT_TEMP_HYST 0x3a | |
45 | #define DTT_CONFIG 0x40 | |
6dedf3d4 HS |
46 | |
47 | int dtt_read(int sensor, int reg) | |
48 | { | |
49 | int dlen = 1; | |
50 | uchar data[2]; | |
51 | ||
52 | /* | |
53 | * Calculate sensor address and register. | |
54 | */ | |
55 | sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */ | |
56 | ||
57 | /* | |
58 | * Now try to read the register. | |
59 | */ | |
60 | if (i2c_read(sensor, reg, 1, data, dlen) != 0) | |
61 | return -1; | |
62 | ||
63 | return (int)data[0]; | |
64 | } /* dtt_read() */ | |
65 | ||
66 | ||
67 | int dtt_write(int sensor, int reg, int val) | |
68 | { | |
69 | uchar data; | |
70 | ||
71 | /* | |
72 | * Calculate sensor address and register. | |
73 | */ | |
74 | sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */ | |
75 | ||
76 | data = (char)(val & 0xff); | |
77 | ||
78 | /* | |
79 | * Write value to register. | |
80 | */ | |
a443d314 | 81 | if (i2c_write(sensor, reg, 1, &data, 1) != 0) |
6dedf3d4 HS |
82 | return 1; |
83 | ||
84 | return 0; | |
85 | } /* dtt_write() */ | |
86 | ||
87 | #define DTT_MANU 0x3e | |
88 | #define DTT_REV 0x3f | |
a443d314 | 89 | #define DTT_CONFIG 0x40 |
6dedf3d4 HS |
90 | #define DTT_ADR 0x48 |
91 | ||
92 | static int _dtt_init(int sensor) | |
93 | { | |
94 | int man; | |
95 | int adr; | |
96 | int rev; | |
97 | ||
98 | if (dtt_write (sensor, DTT_CONFIG, 0x01) < 0) | |
99 | return 1; | |
a443d314 HS |
100 | /* The LM81 needs 400ms to get the correct values ... */ |
101 | udelay (400000); | |
6dedf3d4 HS |
102 | man = dtt_read (sensor, DTT_MANU); |
103 | if (man != 0x01) | |
104 | return 1; | |
105 | adr = dtt_read (sensor, DTT_ADR); | |
106 | if (adr < 0) | |
107 | return 1; | |
108 | rev = dtt_read (sensor, DTT_REV); | |
109 | if (adr < 0) | |
110 | return 1; | |
111 | ||
112 | printf ("DTT: Found LM81@%x Rev: %d\n", adr, rev); | |
6dedf3d4 HS |
113 | return 0; |
114 | } /* _dtt_init() */ | |
115 | ||
116 | ||
117 | int dtt_init (void) | |
118 | { | |
119 | int i; | |
120 | unsigned char sensors[] = CONFIG_DTT_SENSORS; | |
121 | const char *const header = "DTT: "; | |
122 | ||
123 | for (i = 0; i < sizeof(sensors); i++) { | |
124 | if (_dtt_init(sensors[i]) != 0) | |
125 | printf("%s%d FAILED INIT\n", header, i+1); | |
126 | else | |
127 | printf("%s%d is %i C\n", header, i+1, | |
128 | dtt_get_temp(sensors[i])); | |
129 | } | |
130 | ||
131 | return (0); | |
132 | } /* dtt_init() */ | |
133 | ||
134 | #define TEMP_FROM_REG(temp) \ | |
f11033e7 WD |
135 | ((temp)<256?((((temp)&0x1fe) >> 1) * 10) + ((temp) & 1) * 5: \ |
136 | ((((temp)&0x1fe) >> 1) -255) * 10 - ((temp) & 1) * 5) \ | |
6dedf3d4 HS |
137 | |
138 | int dtt_get_temp(int sensor) | |
139 | { | |
140 | int val = dtt_read (sensor, DTT_READ_TEMP); | |
141 | int tmpcnf = dtt_read (sensor, DTT_CONFIG_TEMP); | |
142 | ||
143 | return (TEMP_FROM_REG((val << 1) + ((tmpcnf & 0x80) >> 7))) / 10; | |
144 | } /* dtt_get_temp() */ |