tmp421.c (11220B)
1 /* 2 * Texas Instruments TMP421 temperature sensor. 3 * 4 * Copyright (c) 2016 IBM Corporation. 5 * 6 * Largely inspired by : 7 * 8 * Texas Instruments TMP105 temperature sensor. 9 * 10 * Copyright (C) 2008 Nokia Corporation 11 * Written by Andrzej Zaborowski <andrew@openedhand.com> 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 or 16 * (at your option) version 3 of the License. 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 along 24 * with this program; if not, see <http://www.gnu.org/licenses/>. 25 */ 26 27 #include "qemu/osdep.h" 28 #include "hw/i2c/i2c.h" 29 #include "migration/vmstate.h" 30 #include "qapi/error.h" 31 #include "qapi/visitor.h" 32 #include "qemu/module.h" 33 #include "qom/object.h" 34 35 /* Manufacturer / Device ID's */ 36 #define TMP421_MANUFACTURER_ID 0x55 37 #define TMP421_DEVICE_ID 0x21 38 #define TMP422_DEVICE_ID 0x22 39 #define TMP423_DEVICE_ID 0x23 40 41 typedef struct DeviceInfo { 42 int model; 43 const char *name; 44 } DeviceInfo; 45 46 static const DeviceInfo devices[] = { 47 { TMP421_DEVICE_ID, "tmp421" }, 48 { TMP422_DEVICE_ID, "tmp422" }, 49 { TMP423_DEVICE_ID, "tmp423" }, 50 }; 51 52 struct TMP421State { 53 /*< private >*/ 54 I2CSlave i2c; 55 /*< public >*/ 56 57 int16_t temperature[4]; 58 59 uint8_t status; 60 uint8_t config[2]; 61 uint8_t rate; 62 63 uint8_t len; 64 uint8_t buf[2]; 65 uint8_t pointer; 66 67 }; 68 69 struct TMP421Class { 70 I2CSlaveClass parent_class; 71 DeviceInfo *dev; 72 }; 73 74 #define TYPE_TMP421 "tmp421-generic" 75 OBJECT_DECLARE_TYPE(TMP421State, TMP421Class, TMP421) 76 77 78 /* the TMP421 registers */ 79 #define TMP421_STATUS_REG 0x08 80 #define TMP421_STATUS_BUSY (1 << 7) 81 #define TMP421_CONFIG_REG_1 0x09 82 #define TMP421_CONFIG_RANGE (1 << 2) 83 #define TMP421_CONFIG_SHUTDOWN (1 << 6) 84 #define TMP421_CONFIG_REG_2 0x0A 85 #define TMP421_CONFIG_RC (1 << 2) 86 #define TMP421_CONFIG_LEN (1 << 3) 87 #define TMP421_CONFIG_REN (1 << 4) 88 #define TMP421_CONFIG_REN2 (1 << 5) 89 #define TMP421_CONFIG_REN3 (1 << 6) 90 91 #define TMP421_CONVERSION_RATE_REG 0x0B 92 #define TMP421_ONE_SHOT 0x0F 93 94 #define TMP421_RESET 0xFC 95 #define TMP421_MANUFACTURER_ID_REG 0xFE 96 #define TMP421_DEVICE_ID_REG 0xFF 97 98 #define TMP421_TEMP_MSB0 0x00 99 #define TMP421_TEMP_MSB1 0x01 100 #define TMP421_TEMP_MSB2 0x02 101 #define TMP421_TEMP_MSB3 0x03 102 #define TMP421_TEMP_LSB0 0x10 103 #define TMP421_TEMP_LSB1 0x11 104 #define TMP421_TEMP_LSB2 0x12 105 #define TMP421_TEMP_LSB3 0x13 106 107 static const int32_t mins[2] = { -40000, -55000 }; 108 static const int32_t maxs[2] = { 127000, 150000 }; 109 110 static void tmp421_get_temperature(Object *obj, Visitor *v, const char *name, 111 void *opaque, Error **errp) 112 { 113 TMP421State *s = TMP421(obj); 114 bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE); 115 int offset = ext_range * 64 * 256; 116 int64_t value; 117 int tempid; 118 119 if (sscanf(name, "temperature%d", &tempid) != 1) { 120 error_setg(errp, "error reading %s: %s", name, g_strerror(errno)); 121 return; 122 } 123 124 if (tempid >= 4 || tempid < 0) { 125 error_setg(errp, "error reading %s", name); 126 return; 127 } 128 129 value = ((s->temperature[tempid] - offset) * 1000 + 128) / 256; 130 131 visit_type_int(v, name, &value, errp); 132 } 133 134 /* Units are 0.001 centigrades relative to 0 C. s->temperature is 8.8 135 * fixed point, so units are 1/256 centigrades. A simple ratio will do. 136 */ 137 static void tmp421_set_temperature(Object *obj, Visitor *v, const char *name, 138 void *opaque, Error **errp) 139 { 140 TMP421State *s = TMP421(obj); 141 int64_t temp; 142 bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE); 143 int offset = ext_range * 64 * 256; 144 int tempid; 145 146 if (!visit_type_int(v, name, &temp, errp)) { 147 return; 148 } 149 150 if (temp >= maxs[ext_range] || temp < mins[ext_range]) { 151 error_setg(errp, "value %" PRId64 ".%03" PRIu64 " C is out of range", 152 temp / 1000, temp % 1000); 153 return; 154 } 155 156 if (sscanf(name, "temperature%d", &tempid) != 1) { 157 error_setg(errp, "error reading %s: %s", name, g_strerror(errno)); 158 return; 159 } 160 161 if (tempid >= 4 || tempid < 0) { 162 error_setg(errp, "error reading %s", name); 163 return; 164 } 165 166 s->temperature[tempid] = (int16_t) ((temp * 256 - 128) / 1000) + offset; 167 } 168 169 static void tmp421_read(TMP421State *s) 170 { 171 TMP421Class *sc = TMP421_GET_CLASS(s); 172 173 s->len = 0; 174 175 switch (s->pointer) { 176 case TMP421_MANUFACTURER_ID_REG: 177 s->buf[s->len++] = TMP421_MANUFACTURER_ID; 178 break; 179 case TMP421_DEVICE_ID_REG: 180 s->buf[s->len++] = sc->dev->model; 181 break; 182 case TMP421_CONFIG_REG_1: 183 s->buf[s->len++] = s->config[0]; 184 break; 185 case TMP421_CONFIG_REG_2: 186 s->buf[s->len++] = s->config[1]; 187 break; 188 case TMP421_CONVERSION_RATE_REG: 189 s->buf[s->len++] = s->rate; 190 break; 191 case TMP421_STATUS_REG: 192 s->buf[s->len++] = s->status; 193 break; 194 195 /* FIXME: check for channel enablement in config registers */ 196 case TMP421_TEMP_MSB0: 197 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 8); 198 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0; 199 break; 200 case TMP421_TEMP_MSB1: 201 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 8); 202 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0; 203 break; 204 case TMP421_TEMP_MSB2: 205 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 8); 206 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0; 207 break; 208 case TMP421_TEMP_MSB3: 209 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 8); 210 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0; 211 break; 212 case TMP421_TEMP_LSB0: 213 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0; 214 break; 215 case TMP421_TEMP_LSB1: 216 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0; 217 break; 218 case TMP421_TEMP_LSB2: 219 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0; 220 break; 221 case TMP421_TEMP_LSB3: 222 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0; 223 break; 224 } 225 } 226 227 static void tmp421_reset(I2CSlave *i2c); 228 229 static void tmp421_write(TMP421State *s) 230 { 231 switch (s->pointer) { 232 case TMP421_CONVERSION_RATE_REG: 233 s->rate = s->buf[0]; 234 break; 235 case TMP421_CONFIG_REG_1: 236 s->config[0] = s->buf[0]; 237 break; 238 case TMP421_CONFIG_REG_2: 239 s->config[1] = s->buf[0]; 240 break; 241 case TMP421_RESET: 242 tmp421_reset(I2C_SLAVE(s)); 243 break; 244 } 245 } 246 247 static uint8_t tmp421_rx(I2CSlave *i2c) 248 { 249 TMP421State *s = TMP421(i2c); 250 251 if (s->len < 2) { 252 return s->buf[s->len++]; 253 } else { 254 return 0xff; 255 } 256 } 257 258 static int tmp421_tx(I2CSlave *i2c, uint8_t data) 259 { 260 TMP421State *s = TMP421(i2c); 261 262 if (s->len == 0) { 263 /* first byte is the register pointer for a read or write 264 * operation */ 265 s->pointer = data; 266 s->len++; 267 } else if (s->len == 1) { 268 /* second byte is the data to write. The device only supports 269 * one byte writes */ 270 s->buf[0] = data; 271 tmp421_write(s); 272 } 273 274 return 0; 275 } 276 277 static int tmp421_event(I2CSlave *i2c, enum i2c_event event) 278 { 279 TMP421State *s = TMP421(i2c); 280 281 if (event == I2C_START_RECV) { 282 tmp421_read(s); 283 } 284 285 s->len = 0; 286 return 0; 287 } 288 289 static const VMStateDescription vmstate_tmp421 = { 290 .name = "TMP421", 291 .version_id = 0, 292 .minimum_version_id = 0, 293 .fields = (VMStateField[]) { 294 VMSTATE_UINT8(len, TMP421State), 295 VMSTATE_UINT8_ARRAY(buf, TMP421State, 2), 296 VMSTATE_UINT8(pointer, TMP421State), 297 VMSTATE_UINT8_ARRAY(config, TMP421State, 2), 298 VMSTATE_UINT8(status, TMP421State), 299 VMSTATE_UINT8(rate, TMP421State), 300 VMSTATE_INT16_ARRAY(temperature, TMP421State, 4), 301 VMSTATE_I2C_SLAVE(i2c, TMP421State), 302 VMSTATE_END_OF_LIST() 303 } 304 }; 305 306 static void tmp421_reset(I2CSlave *i2c) 307 { 308 TMP421State *s = TMP421(i2c); 309 TMP421Class *sc = TMP421_GET_CLASS(s); 310 311 memset(s->temperature, 0, sizeof(s->temperature)); 312 s->pointer = 0; 313 314 s->config[0] = 0; /* TMP421_CONFIG_RANGE */ 315 316 /* resistance correction and channel enablement */ 317 switch (sc->dev->model) { 318 case TMP421_DEVICE_ID: 319 s->config[1] = 0x1c; 320 break; 321 case TMP422_DEVICE_ID: 322 s->config[1] = 0x3c; 323 break; 324 case TMP423_DEVICE_ID: 325 s->config[1] = 0x7c; 326 break; 327 } 328 329 s->rate = 0x7; /* 8Hz */ 330 s->status = 0; 331 } 332 333 static void tmp421_realize(DeviceState *dev, Error **errp) 334 { 335 TMP421State *s = TMP421(dev); 336 337 tmp421_reset(&s->i2c); 338 } 339 340 static void tmp421_class_init(ObjectClass *klass, void *data) 341 { 342 DeviceClass *dc = DEVICE_CLASS(klass); 343 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass); 344 TMP421Class *sc = TMP421_CLASS(klass); 345 346 dc->realize = tmp421_realize; 347 k->event = tmp421_event; 348 k->recv = tmp421_rx; 349 k->send = tmp421_tx; 350 dc->vmsd = &vmstate_tmp421; 351 sc->dev = (DeviceInfo *) data; 352 353 object_class_property_add(klass, "temperature0", "int", 354 tmp421_get_temperature, 355 tmp421_set_temperature, NULL, NULL); 356 object_class_property_add(klass, "temperature1", "int", 357 tmp421_get_temperature, 358 tmp421_set_temperature, NULL, NULL); 359 object_class_property_add(klass, "temperature2", "int", 360 tmp421_get_temperature, 361 tmp421_set_temperature, NULL, NULL); 362 object_class_property_add(klass, "temperature3", "int", 363 tmp421_get_temperature, 364 tmp421_set_temperature, NULL, NULL); 365 } 366 367 static const TypeInfo tmp421_info = { 368 .name = TYPE_TMP421, 369 .parent = TYPE_I2C_SLAVE, 370 .instance_size = sizeof(TMP421State), 371 .class_size = sizeof(TMP421Class), 372 .abstract = true, 373 }; 374 375 static void tmp421_register_types(void) 376 { 377 int i; 378 379 type_register_static(&tmp421_info); 380 for (i = 0; i < ARRAY_SIZE(devices); ++i) { 381 TypeInfo ti = { 382 .name = devices[i].name, 383 .parent = TYPE_TMP421, 384 .class_init = tmp421_class_init, 385 .class_data = (void *) &devices[i], 386 }; 387 type_register(&ti); 388 } 389 } 390 391 type_init(tmp421_register_types)