1 /* $NetBSD: owtemp.c,v 1.3 2006/05/05 18:04:42 thorpej Exp $ */ 2 /* $OpenBSD: owtemp.c,v 1.1 2006/03/04 16:27:03 grange Exp $ */ 3 4 /* 5 * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 /* 21 * 1-Wire temperature family type device driver. 22 */ 23 24 #include <sys/cdefs.h> 25 __KERNEL_RCSID(0, "$NetBSD: owtemp.c,v 1.3 2006/05/05 18:04:42 thorpej Exp $"); 26 27 #include <sys/param.h> 28 #include <sys/systm.h> 29 #include <sys/device.h> 30 #include <sys/kernel.h> 31 #include <sys/proc.h> 32 33 #include <dev/sysmon/sysmonvar.h> 34 35 #include <dev/onewire/onewiredevs.h> 36 #include <dev/onewire/onewirereg.h> 37 #include <dev/onewire/onewirevar.h> 38 39 #define DS_CMD_CONVERT 0x44 40 #define DS_CMD_READ_SCRATCHPAD 0xbe 41 42 struct owtemp_softc { 43 struct device sc_dev; 44 45 void * sc_onewire; 46 u_int64_t sc_rom; 47 48 struct envsys_tre_data sc_sensor[1]; 49 struct envsys_basic_info sc_info[1]; 50 51 struct sysmon_envsys sc_sysmon; 52 53 uint32_t (*sc_owtemp_decode)(const uint8_t *); 54 55 int sc_dying; 56 }; 57 58 int owtemp_match(struct device *, struct cfdata *, void *); 59 void owtemp_attach(struct device *, struct device *, void *); 60 int owtemp_detach(struct device *, int); 61 int owtemp_activate(struct device *, enum devact); 62 63 void owtemp_update(void *); 64 65 CFATTACH_DECL(owtemp, sizeof(struct owtemp_softc), 66 owtemp_match, owtemp_attach, owtemp_detach, owtemp_activate); 67 68 extern struct cfdriver owtemp_cd; 69 70 static const struct onewire_matchfam owtemp_fams[] = { 71 { ONEWIRE_FAMILY_DS1920 }, 72 { ONEWIRE_FAMILY_DS18B20 }, 73 { ONEWIRE_FAMILY_DS1822 }, 74 }; 75 76 static const struct envsys_range owtemp_ranges[] = { 77 { 0, 1, ENVSYS_STEMP }, 78 { 1, 0, -1 }, 79 }; 80 81 static int owtemp_gtredata(struct sysmon_envsys *, 82 struct envsys_tre_data *); 83 static int owtemp_streinfo(struct sysmon_envsys *, 84 struct envsys_basic_info *); 85 86 static uint32_t owtemp_decode_ds18b20(const uint8_t *); 87 static uint32_t owtemp_decode_ds1920(const uint8_t *); 88 89 int 90 owtemp_match(struct device *parent, struct cfdata *cf, void *aux) 91 { 92 return (onewire_matchbyfam(aux, owtemp_fams, 93 sizeof(owtemp_fams) /sizeof(owtemp_fams[0]))); 94 } 95 96 void 97 owtemp_attach(struct device *parent, struct device *self, void *aux) 98 { 99 struct owtemp_softc *sc = device_private(self); 100 struct onewire_attach_args *oa = aux; 101 prop_string_t desc; 102 103 sc->sc_onewire = oa->oa_onewire; 104 sc->sc_rom = oa->oa_rom; 105 106 switch(ONEWIRE_ROM_FAMILY_TYPE(sc->sc_rom)) { 107 case ONEWIRE_FAMILY_DS18B20: 108 case ONEWIRE_FAMILY_DS1822: 109 sc->sc_owtemp_decode = owtemp_decode_ds18b20; 110 break; 111 case ONEWIRE_FAMILY_DS1920: 112 sc->sc_owtemp_decode = owtemp_decode_ds1920; 113 break; 114 } 115 116 /* Initialize sensor */ 117 sc->sc_sensor[0].sensor = sc->sc_info[0].sensor = 0; 118 sc->sc_sensor[0].validflags = ENVSYS_FVALID; 119 sc->sc_info[0].validflags = ENVSYS_FVALID; 120 sc->sc_sensor[0].warnflags = ENVSYS_WARN_OK; 121 122 sc->sc_sensor[0].units = sc->sc_info[0].units = ENVSYS_STEMP; 123 desc = prop_dictionary_get(device_properties(&sc->sc_dev), 124 "description"); 125 if (desc != NULL && 126 prop_object_type(desc) == PROP_TYPE_STRING && 127 prop_string_size(desc) > 0) 128 strcpy(sc->sc_info[0].desc, prop_string_cstring_nocopy(desc)); 129 else 130 strcpy(sc->sc_info[0].desc, sc->sc_dev.dv_xname); 131 132 /* Hook into system monitor. */ 133 sc->sc_sysmon.sme_ranges = owtemp_ranges; 134 sc->sc_sysmon.sme_sensor_info = sc->sc_info; 135 sc->sc_sysmon.sme_sensor_data = sc->sc_sensor; 136 sc->sc_sysmon.sme_cookie = sc; 137 138 sc->sc_sysmon.sme_gtredata = owtemp_gtredata; 139 sc->sc_sysmon.sme_streinfo = owtemp_streinfo; 140 141 sc->sc_sysmon.sme_nsensors = 1; 142 sc->sc_sysmon.sme_envsys_version = 1000; 143 144 if (sysmon_envsys_register(&sc->sc_sysmon)) 145 aprint_error("%s: unable to register with sysmon\n", 146 sc->sc_dev.dv_xname); 147 148 #if 0 /* Old OpenBSD code */ 149 strlcpy(sc->sc_sensor.device, sc->sc_dev.dv_xname, 150 sizeof(sc->sc_sensor.device)); 151 sc->sc_sensor.type = SENSOR_TEMP; 152 strlcpy(sc->sc_sensor.desc, "Temp", sizeof(sc->sc_sensor.desc)); 153 154 if (sensor_task_register(sc, owtemp_update, 5)) { 155 printf(": unable to register update task\n"); 156 return; 157 } 158 sensor_add(&sc->sc_sensor); 159 #endif 160 161 printf("\n"); 162 } 163 164 int 165 owtemp_detach(struct device *self, int flags) 166 { 167 struct owtemp_softc *sc = device_private(self); 168 169 sysmon_envsys_unregister(&sc->sc_sysmon); 170 171 return 0; 172 } 173 174 int 175 owtemp_activate(struct device *self, enum devact act) 176 { 177 struct owtemp_softc *sc = device_private(self); 178 179 switch (act) { 180 case DVACT_ACTIVATE: 181 return (EOPNOTSUPP); 182 case DVACT_DEACTIVATE: 183 sc->sc_dying = 1; 184 break; 185 } 186 187 return (0); 188 } 189 190 void 191 owtemp_update(void *arg) 192 { 193 struct owtemp_softc *sc = arg; 194 u_int8_t data[9]; 195 196 onewire_lock(sc->sc_onewire, 0); 197 if (onewire_reset(sc->sc_onewire) != 0) 198 goto done; 199 onewire_matchrom(sc->sc_onewire, sc->sc_rom); 200 201 /* 202 * Start temperature conversion. The conversion takes up to 750ms. 203 * After sending the command, the data line must be held high for 204 * at least 750ms to provide power during the conversion process. 205 * As such, no other activity may take place on the 1-Wire bus for 206 * at least this period. 207 */ 208 onewire_write_byte(sc->sc_onewire, DS_CMD_CONVERT); 209 tsleep(sc, PRIBIO, "owtemp", hz); 210 211 if (onewire_reset(sc->sc_onewire) != 0) 212 goto done; 213 onewire_matchrom(sc->sc_onewire, sc->sc_rom); 214 215 /* 216 * The result of the temperature measurement is placed in the 217 * first two bytes of the scratchpad. 218 */ 219 onewire_write_byte(sc->sc_onewire, DS_CMD_READ_SCRATCHPAD); 220 onewire_read_block(sc->sc_onewire, data, 9); 221 #if 0 222 if (onewire_crc(data, 8) == data[8]) { 223 sc->sc_sensor.value = 273150000 + 224 (int)((u_int16_t)data[1] << 8 | data[0]) * 500000; 225 } 226 #endif 227 228 sc->sc_sensor[0].cur.data_us = sc->sc_owtemp_decode(data); 229 sc->sc_sensor[0].validflags |= ENVSYS_FCURVALID; 230 231 done: 232 onewire_unlock(sc->sc_onewire); 233 } 234 235 static int 236 owtemp_gtredata(struct sysmon_envsys *sme, struct envsys_tre_data *tred) 237 { 238 struct owtemp_softc *sc = sme->sme_cookie; 239 240 owtemp_update(sc); 241 *tred = sc->sc_sensor[tred->sensor]; 242 243 return 0; 244 } 245 246 static int 247 owtemp_streinfo(struct sysmon_envsys *sme, struct envsys_basic_info *binfo) 248 { 249 struct owtemp_softc *sc = sme->sme_cookie; 250 251 onewire_lock(sc->sc_onewire,0); /* Also locks our instance */ 252 253 memcpy(sc->sc_info[binfo->sensor].desc, binfo->desc, 254 sizeof(sc->sc_info[binfo->sensor].desc)); 255 sc->sc_info[binfo->sensor].desc[ 256 sizeof(sc->sc_info[binfo->sensor].desc) - 1] = '\0'; 257 258 onewire_unlock(sc->sc_onewire); 259 260 binfo->validflags = ENVSYS_FVALID; 261 262 return 0; 263 } 264 265 static uint32_t 266 owtemp_decode_ds18b20(const uint8_t *buf) 267 { 268 int temp; 269 270 /* 271 * Sign-extend the MSB byte, and add in the fractions of a 272 * degree contained in the LSB (precision 1/16th DegC). 273 */ 274 temp = (int8_t)buf[1]; 275 temp = (temp << 8) | buf[0]; 276 277 /* 278 * Conversion to uK is simple. 279 */ 280 return (temp * 62500 + 273150000); 281 } 282 283 static uint32_t 284 owtemp_decode_ds1920(const uint8_t *buf) 285 { 286 int temp; 287 288 /* 289 * Sign-extend the MSB byte, and add in the fractions of a 290 * degree contained in the LSB (precision 1/2 DegC). 291 */ 292 temp = (int8_t)buf[1]; 293 temp = (temp << 8) | buf[0]; 294 295 /* Convert to uK */ 296 return (temp * 500000 + 273150000); 297 } 298