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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 | /* * (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> #ifdef CONFIG_DTT_LM81 #if !defined(CFG_EEPROM_PAGE_WRITE_ENABLE) || \ (CFG_EEPROM_PAGE_WRITE_BITS < 1) # error "CFG_EEPROM_PAGE_WRITE_ENABLE must be defined and CFG_EEPROM_PAGE_WRITE_BITS must be greater than 1 to use CONFIG_DTT_LM81" #endif #include <i2c.h> #include <dtt.h> /* * Device code */ #define DTT_I2C_DEV_CODE 0x2c /* ON Semi's LM81 device */ 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() */ #endif /* CONFIG_DTT_LM81 */ |