lm75.c revision 1.9
1 /* $NetBSD: lm75.c,v 1.9 2006/05/17 00:10:54 kiyohara Exp $ */ 2 3 /* 4 * Copyright (c) 2003 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Jason R. Thorpe for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/device.h> 41 #include <sys/kernel.h> 42 43 #include <dev/sysmon/sysmonvar.h> 44 45 #include <dev/i2c/i2cvar.h> 46 #include <dev/i2c/lm75reg.h> 47 48 struct lmtemp_softc { 49 struct device sc_dev; 50 i2c_tag_t sc_tag; 51 int sc_address; 52 53 struct envsys_tre_data sc_sensor[1]; 54 struct envsys_basic_info sc_info[1]; 55 56 struct sysmon_envsys sc_sysmon; 57 58 uint32_t (*sc_lmtemp_decode)(const uint8_t *); 59 }; 60 61 static int lmtemp_match(struct device *, struct cfdata *, void *); 62 static void lmtemp_attach(struct device *, struct device *, void *); 63 64 CFATTACH_DECL(lmtemp, sizeof(struct lmtemp_softc), 65 lmtemp_match, lmtemp_attach, NULL, NULL); 66 67 static int lmtemp_gtredata(struct sysmon_envsys *, 68 struct envsys_tre_data *); 69 static int lmtemp_streinfo(struct sysmon_envsys *, 70 struct envsys_basic_info *); 71 72 static const struct envsys_range lmtemp_ranges[] = { 73 { 0, 1, ENVSYS_STEMP }, 74 { 1, 0, -1 }, 75 }; 76 77 static int lmtemp_config_write(struct lmtemp_softc *, uint8_t); 78 static uint32_t lmtemp_decode_lm75(const uint8_t *); 79 static uint32_t lmtemp_decode_ds75(const uint8_t *); 80 static uint32_t lmtemp_decode_lm77(const uint8_t *); 81 82 enum { 83 lmtemp_lm75 = 0, 84 lmtemp_ds75, 85 lmtemp_lm77, 86 }; 87 static const struct { 88 int lmtemp_type; 89 const char *lmtemp_name; 90 int lmtemp_addrmask; 91 int lmtemp_addr; 92 uint32_t (*lmtemp_decode)(const uint8_t *); 93 } lmtemptbl[] = { 94 { lmtemp_lm75, "LM75", 95 LM75_ADDRMASK, LM75_ADDR, lmtemp_decode_lm75 }, 96 { lmtemp_ds75, "DS75", 97 LM75_ADDRMASK, LM75_ADDR, lmtemp_decode_ds75 }, 98 { lmtemp_lm77, "LM77", 99 LM77_ADDRMASK, LM77_ADDR, lmtemp_decode_lm77 }, 100 101 { -1, NULL, 102 0, 0, NULL } 103 }; 104 105 static int 106 lmtemp_match(struct device *parent, struct cfdata *cf, void *aux) 107 { 108 struct i2c_attach_args *ia = aux; 109 int i; 110 111 for (i = 0; lmtemptbl[i].lmtemp_type != -1 ; i++) 112 if (lmtemptbl[i].lmtemp_type == cf->cf_flags) 113 break; 114 if (lmtemptbl[i].lmtemp_type == -1) 115 return (0); 116 117 if ((ia->ia_addr & lmtemptbl[i].lmtemp_addrmask) == 118 lmtemptbl[i].lmtemp_addr) 119 return (1); 120 121 return (0); 122 } 123 124 static void 125 lmtemp_attach(struct device *parent, struct device *self, void *aux) 126 { 127 struct lmtemp_softc *sc = device_private(self); 128 struct i2c_attach_args *ia = aux; 129 prop_string_t desc; 130 int i; 131 132 for (i = 0; lmtemptbl[i].lmtemp_type != -1 ; i++) 133 if (lmtemptbl[i].lmtemp_type == 134 device_cfdata(&sc->sc_dev)->cf_flags) 135 break; 136 137 sc->sc_tag = ia->ia_tag; 138 sc->sc_address = ia->ia_addr; 139 140 aprint_naive(": Temperature Sensor\n"); 141 aprint_normal(": %s Temperature Sensor\n", lmtemptbl[i].lmtemp_name); 142 143 /* Set the configuration of the LM75 to defaults. */ 144 iic_acquire_bus(sc->sc_tag, I2C_F_POLL); 145 if (lmtemp_config_write(sc, 0) != 0) { 146 aprint_error("%s: unable to write config register\n", 147 sc->sc_dev.dv_xname); 148 iic_release_bus(sc->sc_tag, I2C_F_POLL); 149 return; 150 } 151 iic_release_bus(sc->sc_tag, I2C_F_POLL); 152 153 /* Initialize sensor data. */ 154 sc->sc_sensor[0].sensor = sc->sc_info[0].sensor = 0; 155 sc->sc_sensor[0].validflags = ENVSYS_FVALID; 156 sc->sc_info[0].validflags = ENVSYS_FVALID; 157 sc->sc_sensor[0].warnflags = ENVSYS_WARN_OK; 158 159 sc->sc_sensor[0].units = sc->sc_info[0].units = ENVSYS_STEMP; 160 desc = prop_dictionary_get(device_properties(&sc->sc_dev), 161 "description"); 162 if (desc != NULL && 163 prop_object_type(desc) == PROP_TYPE_STRING && 164 prop_string_size(desc) > 0) 165 strcpy(sc->sc_info[0].desc, prop_string_cstring_nocopy(desc)); 166 else 167 strcpy(sc->sc_info[0].desc, sc->sc_dev.dv_xname); 168 169 sc->sc_lmtemp_decode = lmtemptbl[i].lmtemp_decode; 170 171 /* Hook into system monitor. */ 172 sc->sc_sysmon.sme_ranges = lmtemp_ranges; 173 sc->sc_sysmon.sme_sensor_info = sc->sc_info; 174 sc->sc_sysmon.sme_sensor_data = sc->sc_sensor; 175 sc->sc_sysmon.sme_cookie = sc; 176 177 sc->sc_sysmon.sme_gtredata = lmtemp_gtredata; 178 sc->sc_sysmon.sme_streinfo = lmtemp_streinfo; 179 180 sc->sc_sysmon.sme_nsensors = 1; 181 sc->sc_sysmon.sme_envsys_version = 1000; 182 183 if (sysmon_envsys_register(&sc->sc_sysmon)) 184 aprint_error("%s: unable to register with sysmon\n", 185 sc->sc_dev.dv_xname); 186 } 187 188 static int 189 lmtemp_config_write(struct lmtemp_softc *sc, uint8_t val) 190 { 191 uint8_t cmdbuf[2]; 192 193 cmdbuf[0] = LM75_REG_CONFIG; 194 cmdbuf[1] = val; 195 196 return (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, 197 sc->sc_address, cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)); 198 } 199 200 static int 201 lmtemp_temp_read(struct lmtemp_softc *sc, uint8_t which, uint32_t *valp) 202 { 203 int error; 204 uint8_t cmdbuf[1]; 205 uint8_t buf[LM75_TEMP_LEN]; 206 207 cmdbuf[0] = which; 208 209 error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, 210 sc->sc_address, cmdbuf, 1, buf, LM75_TEMP_LEN, 0); 211 if (error) 212 return (error); 213 214 *valp = sc->sc_lmtemp_decode(buf); 215 return (0); 216 } 217 218 static void 219 lmtemp_refresh_sensor_data(struct lmtemp_softc *sc) 220 { 221 uint32_t val; 222 int error; 223 224 error = lmtemp_temp_read(sc, LM75_REG_TEMP, &val); 225 if (error) { 226 #if 0 227 printf("%s: unable to read temperature, error = %d\n", 228 sc->sc_dev.dv_xname, error); 229 #endif 230 sc->sc_sensor[0].validflags &= ~ENVSYS_FCURVALID; 231 return; 232 } 233 234 sc->sc_sensor[0].cur.data_us = val; 235 sc->sc_sensor[0].validflags |= ENVSYS_FCURVALID; 236 } 237 238 static int 239 lmtemp_gtredata(struct sysmon_envsys *sme, struct envsys_tre_data *tred) 240 { 241 struct lmtemp_softc *sc = sme->sme_cookie; 242 243 iic_acquire_bus(sc->sc_tag, 0); /* also locks our instance */ 244 245 lmtemp_refresh_sensor_data(sc); 246 *tred = sc->sc_sensor[tred->sensor]; 247 248 iic_release_bus(sc->sc_tag, 0); /* also unlocks our instance */ 249 250 return (0); 251 } 252 253 static int 254 lmtemp_streinfo(struct sysmon_envsys *sme, struct envsys_basic_info *binfo) 255 { 256 struct lmtemp_softc *sc = sme->sme_cookie; 257 258 iic_acquire_bus(sc->sc_tag, 0); /* also locks our instance */ 259 260 memcpy(sc->sc_info[binfo->sensor].desc, binfo->desc, 261 sizeof(sc->sc_info[binfo->sensor].desc)); 262 sc->sc_info[binfo->sensor].desc[ 263 sizeof(sc->sc_info[binfo->sensor].desc) - 1] = '\0'; 264 265 iic_release_bus(sc->sc_tag, 0); /* also unlocks our instance */ 266 267 binfo->validflags = ENVSYS_FVALID; 268 269 return (0); 270 } 271 272 static uint32_t 273 lmtemp_decode_lm75(const uint8_t *buf) 274 { 275 int neg, temp; 276 uint32_t val; 277 278 if (buf[0] & 1) { 279 /* Below 0C */ 280 temp = ~buf[1] + 1; 281 neg = 1; 282 } else { 283 temp = buf[1]; 284 neg = 0; 285 } 286 287 /* Temp is given in 1/2 deg. C, we convert to uK. */ 288 val = ((neg ? -temp : temp) / 2) * 1000000 + 273150000; 289 if (temp & 1) { 290 if (neg) 291 val -= 500000; 292 else 293 val += 500000; 294 } 295 296 return (val); 297 } 298 299 static uint32_t 300 lmtemp_decode_ds75(const uint8_t *buf) 301 { 302 int temp; 303 304 /* 305 * Sign-extend the MSB byte, and add in the fractions of a 306 * degree contained in the LSB (precision 1/16th DegC). 307 */ 308 temp = (int8_t)buf[0]; 309 temp = (temp << 4) | ((buf[1] >> 4) & 0xf); 310 311 /* 312 * Conversion to uK is simple. 313 */ 314 return (temp * 62500 + 273150000); 315 } 316 317 static uint32_t 318 lmtemp_decode_lm77(const uint8_t *buf) 319 { 320 int temp; 321 uint32_t val; 322 323 /* 324 * Describe each bits of temperature registers on LM77. 325 * D15 - D12: Sign 326 * D11 - D3 : Bit8(MSB) - Bit0 327 */ 328 temp = (int8_t)buf[0]; 329 temp = (temp << 5) | (buf[1] >> 3); 330 331 /* Temp is given in 1/2 deg. C, we convert to uK. */ 332 val = temp * 500000 + 273150000; 333 334 return (val); 335 } 336 337
Indexes created Thu Oct 02 01:09:59 GMT 2025