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
34 /* Manufacturer / Device ID's */
35 #define TMP421_MANUFACTURER_ID 0x55
36 #define TMP421_DEVICE_ID 0x21
37 #define TMP422_DEVICE_ID 0x22
38 #define TMP423_DEVICE_ID 0x23
39
40 typedef struct DeviceInfo {
41 int model;
42 const char *name;
43 } DeviceInfo;
44
45 static const DeviceInfo devices[] = {
46 { TMP421_DEVICE_ID, "tmp421" },
47 { TMP422_DEVICE_ID, "tmp422" },
48 { TMP423_DEVICE_ID, "tmp423" },
49 };
50
51 typedef struct TMP421State {
52 /*< private >*/
53 I2CSlave i2c;
54 /*< public >*/
55
56 int16_t temperature[4];
57
58 uint8_t status;
59 uint8_t config[2];
60 uint8_t rate;
61
62 uint8_t len;
63 uint8_t buf[2];
64 uint8_t pointer;
65
66 } TMP421State;
67
68 typedef struct TMP421Class {
69 I2CSlaveClass parent_class;
70 DeviceInfo *dev;
71 } TMP421Class;
72
73 #define TYPE_TMP421 "tmp421-generic"
74 #define TMP421(obj) OBJECT_CHECK(TMP421State, (obj), TYPE_TMP421)
75
76 #define TMP421_CLASS(klass) \
77 OBJECT_CLASS_CHECK(TMP421Class, (klass), TYPE_TMP421)
78 #define TMP421_GET_CLASS(obj) \
79 OBJECT_GET_CLASS(TMP421Class, (obj), TYPE_TMP421)
80
81 /* the TMP421 registers */
82 #define TMP421_STATUS_REG 0x08
83 #define TMP421_STATUS_BUSY (1 << 7)
84 #define TMP421_CONFIG_REG_1 0x09
85 #define TMP421_CONFIG_RANGE (1 << 2)
86 #define TMP421_CONFIG_SHUTDOWN (1 << 6)
87 #define TMP421_CONFIG_REG_2 0x0A
88 #define TMP421_CONFIG_RC (1 << 2)
89 #define TMP421_CONFIG_LEN (1 << 3)
90 #define TMP421_CONFIG_REN (1 << 4)
91 #define TMP421_CONFIG_REN2 (1 << 5)
92 #define TMP421_CONFIG_REN3 (1 << 6)
93
94 #define TMP421_CONVERSION_RATE_REG 0x0B
95 #define TMP421_ONE_SHOT 0x0F
96
97 #define TMP421_RESET 0xFC
98 #define TMP421_MANUFACTURER_ID_REG 0xFE
99 #define TMP421_DEVICE_ID_REG 0xFF
100
101 #define TMP421_TEMP_MSB0 0x00
102 #define TMP421_TEMP_MSB1 0x01
103 #define TMP421_TEMP_MSB2 0x02
104 #define TMP421_TEMP_MSB3 0x03
105 #define TMP421_TEMP_LSB0 0x10
106 #define TMP421_TEMP_LSB1 0x11
107 #define TMP421_TEMP_LSB2 0x12
108 #define TMP421_TEMP_LSB3 0x13
109
110 static const int32_t mins[2] = { -40000, -55000 };
111 static const int32_t maxs[2] = { 127000, 150000 };
112
tmp421_get_temperature(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)113 static void tmp421_get_temperature(Object *obj, Visitor *v, const char *name,
114 void *opaque, Error **errp)
115 {
116 TMP421State *s = TMP421(obj);
117 bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
118 int offset = ext_range * 64 * 256;
119 int64_t value;
120 int tempid;
121
122 if (sscanf(name, "temperature%d", &tempid) != 1) {
123 error_setg(errp, "error reading %s: %s", name, g_strerror(errno));
124 return;
125 }
126
127 if (tempid >= 4 || tempid < 0) {
128 error_setg(errp, "error reading %s", name);
129 return;
130 }
131
132 value = ((s->temperature[tempid] - offset) * 1000 + 128) / 256;
133
134 visit_type_int(v, name, &value, errp);
135 }
136
137 /* Units are 0.001 centigrades relative to 0 C. s->temperature is 8.8
138 * fixed point, so units are 1/256 centigrades. A simple ratio will do.
139 */
tmp421_set_temperature(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)140 static void tmp421_set_temperature(Object *obj, Visitor *v, const char *name,
141 void *opaque, Error **errp)
142 {
143 TMP421State *s = TMP421(obj);
144 Error *local_err = NULL;
145 int64_t temp;
146 bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
147 int offset = ext_range * 64 * 256;
148 int tempid;
149
150 visit_type_int(v, name, &temp, &local_err);
151 if (local_err) {
152 error_propagate(errp, local_err);
153 return;
154 }
155
156 if (temp >= maxs[ext_range] || temp < mins[ext_range]) {
157 error_setg(errp, "value %" PRId64 ".%03" PRIu64 " C is out of range",
158 temp / 1000, temp % 1000);
159 return;
160 }
161
162 if (sscanf(name, "temperature%d", &tempid) != 1) {
163 error_setg(errp, "error reading %s: %s", name, g_strerror(errno));
164 return;
165 }
166
167 if (tempid >= 4 || tempid < 0) {
168 error_setg(errp, "error reading %s", name);
169 return;
170 }
171
172 s->temperature[tempid] = (int16_t) ((temp * 256 - 128) / 1000) + offset;
173 }
174
tmp421_read(TMP421State * s)175 static void tmp421_read(TMP421State *s)
176 {
177 TMP421Class *sc = TMP421_GET_CLASS(s);
178
179 s->len = 0;
180
181 switch (s->pointer) {
182 case TMP421_MANUFACTURER_ID_REG:
183 s->buf[s->len++] = TMP421_MANUFACTURER_ID;
184 break;
185 case TMP421_DEVICE_ID_REG:
186 s->buf[s->len++] = sc->dev->model;
187 break;
188 case TMP421_CONFIG_REG_1:
189 s->buf[s->len++] = s->config[0];
190 break;
191 case TMP421_CONFIG_REG_2:
192 s->buf[s->len++] = s->config[1];
193 break;
194 case TMP421_CONVERSION_RATE_REG:
195 s->buf[s->len++] = s->rate;
196 break;
197 case TMP421_STATUS_REG:
198 s->buf[s->len++] = s->status;
199 break;
200
201 /* FIXME: check for channel enablement in config registers */
202 case TMP421_TEMP_MSB0:
203 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 8);
204 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
205 break;
206 case TMP421_TEMP_MSB1:
207 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 8);
208 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
209 break;
210 case TMP421_TEMP_MSB2:
211 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 8);
212 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
213 break;
214 case TMP421_TEMP_MSB3:
215 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 8);
216 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
217 break;
218 case TMP421_TEMP_LSB0:
219 s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
220 break;
221 case TMP421_TEMP_LSB1:
222 s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
223 break;
224 case TMP421_TEMP_LSB2:
225 s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
226 break;
227 case TMP421_TEMP_LSB3:
228 s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
229 break;
230 }
231 }
232
233 static void tmp421_reset(I2CSlave *i2c);
234
tmp421_write(TMP421State * s)235 static void tmp421_write(TMP421State *s)
236 {
237 switch (s->pointer) {
238 case TMP421_CONVERSION_RATE_REG:
239 s->rate = s->buf[0];
240 break;
241 case TMP421_CONFIG_REG_1:
242 s->config[0] = s->buf[0];
243 break;
244 case TMP421_CONFIG_REG_2:
245 s->config[1] = s->buf[0];
246 break;
247 case TMP421_RESET:
248 tmp421_reset(I2C_SLAVE(s));
249 break;
250 }
251 }
252
tmp421_rx(I2CSlave * i2c)253 static uint8_t tmp421_rx(I2CSlave *i2c)
254 {
255 TMP421State *s = TMP421(i2c);
256
257 if (s->len < 2) {
258 return s->buf[s->len++];
259 } else {
260 return 0xff;
261 }
262 }
263
tmp421_tx(I2CSlave * i2c,uint8_t data)264 static int tmp421_tx(I2CSlave *i2c, uint8_t data)
265 {
266 TMP421State *s = TMP421(i2c);
267
268 if (s->len == 0) {
269 /* first byte is the register pointer for a read or write
270 * operation */
271 s->pointer = data;
272 s->len++;
273 } else if (s->len == 1) {
274 /* second byte is the data to write. The device only supports
275 * one byte writes */
276 s->buf[0] = data;
277 tmp421_write(s);
278 }
279
280 return 0;
281 }
282
tmp421_event(I2CSlave * i2c,enum i2c_event event)283 static int tmp421_event(I2CSlave *i2c, enum i2c_event event)
284 {
285 TMP421State *s = TMP421(i2c);
286
287 if (event == I2C_START_RECV) {
288 tmp421_read(s);
289 }
290
291 s->len = 0;
292 return 0;
293 }
294
295 static const VMStateDescription vmstate_tmp421 = {
296 .name = "TMP421",
297 .version_id = 0,
298 .minimum_version_id = 0,
299 .fields = (VMStateField[]) {
300 VMSTATE_UINT8(len, TMP421State),
301 VMSTATE_UINT8_ARRAY(buf, TMP421State, 2),
302 VMSTATE_UINT8(pointer, TMP421State),
303 VMSTATE_UINT8_ARRAY(config, TMP421State, 2),
304 VMSTATE_UINT8(status, TMP421State),
305 VMSTATE_UINT8(rate, TMP421State),
306 VMSTATE_INT16_ARRAY(temperature, TMP421State, 4),
307 VMSTATE_I2C_SLAVE(i2c, TMP421State),
308 VMSTATE_END_OF_LIST()
309 }
310 };
311
tmp421_reset(I2CSlave * i2c)312 static void tmp421_reset(I2CSlave *i2c)
313 {
314 TMP421State *s = TMP421(i2c);
315 TMP421Class *sc = TMP421_GET_CLASS(s);
316
317 memset(s->temperature, 0, sizeof(s->temperature));
318 s->pointer = 0;
319
320 s->config[0] = 0; /* TMP421_CONFIG_RANGE */
321
322 /* resistance correction and channel enablement */
323 switch (sc->dev->model) {
324 case TMP421_DEVICE_ID:
325 s->config[1] = 0x1c;
326 break;
327 case TMP422_DEVICE_ID:
328 s->config[1] = 0x3c;
329 break;
330 case TMP423_DEVICE_ID:
331 s->config[1] = 0x7c;
332 break;
333 }
334
335 s->rate = 0x7; /* 8Hz */
336 s->status = 0;
337 }
338
tmp421_realize(DeviceState * dev,Error ** errp)339 static void tmp421_realize(DeviceState *dev, Error **errp)
340 {
341 TMP421State *s = TMP421(dev);
342
343 tmp421_reset(&s->i2c);
344 }
345
tmp421_initfn(Object * obj)346 static void tmp421_initfn(Object *obj)
347 {
348 object_property_add(obj, "temperature0", "int",
349 tmp421_get_temperature,
350 tmp421_set_temperature, NULL, NULL, NULL);
351 object_property_add(obj, "temperature1", "int",
352 tmp421_get_temperature,
353 tmp421_set_temperature, NULL, NULL, NULL);
354 object_property_add(obj, "temperature2", "int",
355 tmp421_get_temperature,
356 tmp421_set_temperature, NULL, NULL, NULL);
357 object_property_add(obj, "temperature3", "int",
358 tmp421_get_temperature,
359 tmp421_set_temperature, NULL, NULL, NULL);
360 }
361
tmp421_class_init(ObjectClass * klass,void * data)362 static void tmp421_class_init(ObjectClass *klass, void *data)
363 {
364 DeviceClass *dc = DEVICE_CLASS(klass);
365 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
366 TMP421Class *sc = TMP421_CLASS(klass);
367
368 dc->realize = tmp421_realize;
369 k->event = tmp421_event;
370 k->recv = tmp421_rx;
371 k->send = tmp421_tx;
372 dc->vmsd = &vmstate_tmp421;
373 sc->dev = (DeviceInfo *) data;
374 }
375
376 static const TypeInfo tmp421_info = {
377 .name = TYPE_TMP421,
378 .parent = TYPE_I2C_SLAVE,
379 .instance_size = sizeof(TMP421State),
380 .class_size = sizeof(TMP421Class),
381 .instance_init = tmp421_initfn,
382 .abstract = true,
383 };
384
tmp421_register_types(void)385 static void tmp421_register_types(void)
386 {
387 int i;
388
389 type_register_static(&tmp421_info);
390 for (i = 0; i < ARRAY_SIZE(devices); ++i) {
391 TypeInfo ti = {
392 .name = devices[i].name,
393 .parent = TYPE_TMP421,
394 .class_init = tmp421_class_init,
395 .class_data = (void *) &devices[i],
396 };
397 type_register(&ti);
398 }
399 }
400
401 type_init(tmp421_register_types)
402