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tmp401.c
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1 /* tmp401.c
2  *
3  * Copyright (C) 2007,2008 Hans de Goede <[email protected]>
4  * Preliminary tmp411 support by:
5  * Gabriel Konat, Sander Leget, Wouter Willems
6  * Copyright (C) 2009 Andre Prendel <[email protected]>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 /*
24  * Driver for the Texas Instruments TMP401 SMBUS temperature sensor IC.
25  *
26  * Note this IC is in some aspect similar to the LM90, but it has quite a
27  * few differences too, for example the local temp has a higher resolution
28  * and thus has 16 bits registers for its value and limit instead of 8 bits.
29  */
30 
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/slab.h>
34 #include <linux/jiffies.h>
35 #include <linux/i2c.h>
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 #include <linux/err.h>
39 #include <linux/mutex.h>
40 #include <linux/sysfs.h>
41 
42 /* Addresses to scan */
43 static const unsigned short normal_i2c[] = { 0x4c, I2C_CLIENT_END };
44 
45 enum chips { tmp401, tmp411 };
46 
47 /*
48  * The TMP401 registers, note some registers have different addresses for
49  * reading and writing
50  */
51 #define TMP401_STATUS 0x02
52 #define TMP401_CONFIG_READ 0x03
53 #define TMP401_CONFIG_WRITE 0x09
54 #define TMP401_CONVERSION_RATE_READ 0x04
55 #define TMP401_CONVERSION_RATE_WRITE 0x0A
56 #define TMP401_TEMP_CRIT_HYST 0x21
57 #define TMP401_CONSECUTIVE_ALERT 0x22
58 #define TMP401_MANUFACTURER_ID_REG 0xFE
59 #define TMP401_DEVICE_ID_REG 0xFF
60 #define TMP411_N_FACTOR_REG 0x18
61 
62 static const u8 TMP401_TEMP_MSB[2] = { 0x00, 0x01 };
63 static const u8 TMP401_TEMP_LSB[2] = { 0x15, 0x10 };
64 static const u8 TMP401_TEMP_LOW_LIMIT_MSB_READ[2] = { 0x06, 0x08 };
65 static const u8 TMP401_TEMP_LOW_LIMIT_MSB_WRITE[2] = { 0x0C, 0x0E };
66 static const u8 TMP401_TEMP_LOW_LIMIT_LSB[2] = { 0x17, 0x14 };
67 static const u8 TMP401_TEMP_HIGH_LIMIT_MSB_READ[2] = { 0x05, 0x07 };
68 static const u8 TMP401_TEMP_HIGH_LIMIT_MSB_WRITE[2] = { 0x0B, 0x0D };
69 static const u8 TMP401_TEMP_HIGH_LIMIT_LSB[2] = { 0x16, 0x13 };
70 /* These are called the THERM limit / hysteresis / mask in the datasheet */
71 static const u8 TMP401_TEMP_CRIT_LIMIT[2] = { 0x20, 0x19 };
72 
73 static const u8 TMP411_TEMP_LOWEST_MSB[2] = { 0x30, 0x34 };
74 static const u8 TMP411_TEMP_LOWEST_LSB[2] = { 0x31, 0x35 };
75 static const u8 TMP411_TEMP_HIGHEST_MSB[2] = { 0x32, 0x36 };
76 static const u8 TMP411_TEMP_HIGHEST_LSB[2] = { 0x33, 0x37 };
77 
78 /* Flags */
79 #define TMP401_CONFIG_RANGE 0x04
80 #define TMP401_CONFIG_SHUTDOWN 0x40
81 #define TMP401_STATUS_LOCAL_CRIT 0x01
82 #define TMP401_STATUS_REMOTE_CRIT 0x02
83 #define TMP401_STATUS_REMOTE_OPEN 0x04
84 #define TMP401_STATUS_REMOTE_LOW 0x08
85 #define TMP401_STATUS_REMOTE_HIGH 0x10
86 #define TMP401_STATUS_LOCAL_LOW 0x20
87 #define TMP401_STATUS_LOCAL_HIGH 0x40
88 
89 /* Manufacturer / Device ID's */
90 #define TMP401_MANUFACTURER_ID 0x55
91 #define TMP401_DEVICE_ID 0x11
92 #define TMP411_DEVICE_ID 0x12
93 
94 /*
95  * Driver data (common to all clients)
96  */
97 
98 static const struct i2c_device_id tmp401_id[] = {
99  { "tmp401", tmp401 },
100  { "tmp411", tmp411 },
101  { }
102 };
103 MODULE_DEVICE_TABLE(i2c, tmp401_id);
104 
105 /*
106  * Client data (each client gets its own)
107  */
108 
109 struct tmp401_data {
110  struct device *hwmon_dev;
112  char valid; /* zero until following fields are valid */
113  unsigned long last_updated; /* in jiffies */
114  enum chips kind;
115 
116  /* register values */
119  u16 temp[2];
126 };
127 
128 /*
129  * Sysfs attr show / store functions
130  */
131 
132 static int tmp401_register_to_temp(u16 reg, u8 config)
133 {
134  int temp = reg;
135 
136  if (config & TMP401_CONFIG_RANGE)
137  temp -= 64 * 256;
138 
139  return (temp * 625 + 80) / 160;
140 }
141 
142 static u16 tmp401_temp_to_register(long temp, u8 config)
143 {
144  if (config & TMP401_CONFIG_RANGE) {
145  temp = SENSORS_LIMIT(temp, -64000, 191000);
146  temp += 64000;
147  } else
148  temp = SENSORS_LIMIT(temp, 0, 127000);
149 
150  return (temp * 160 + 312) / 625;
151 }
152 
153 static int tmp401_crit_register_to_temp(u8 reg, u8 config)
154 {
155  int temp = reg;
156 
157  if (config & TMP401_CONFIG_RANGE)
158  temp -= 64;
159 
160  return temp * 1000;
161 }
162 
163 static u8 tmp401_crit_temp_to_register(long temp, u8 config)
164 {
165  if (config & TMP401_CONFIG_RANGE) {
166  temp = SENSORS_LIMIT(temp, -64000, 191000);
167  temp += 64000;
168  } else
169  temp = SENSORS_LIMIT(temp, 0, 127000);
170 
171  return (temp + 500) / 1000;
172 }
173 
174 static struct tmp401_data *tmp401_update_device_reg16(
175  struct i2c_client *client, struct tmp401_data *data)
176 {
177  int i;
178 
179  for (i = 0; i < 2; i++) {
180  /*
181  * High byte must be read first immediately followed
182  * by the low byte
183  */
184  data->temp[i] = i2c_smbus_read_byte_data(client,
185  TMP401_TEMP_MSB[i]) << 8;
186  data->temp[i] |= i2c_smbus_read_byte_data(client,
187  TMP401_TEMP_LSB[i]);
188  data->temp_low[i] = i2c_smbus_read_byte_data(client,
189  TMP401_TEMP_LOW_LIMIT_MSB_READ[i]) << 8;
190  data->temp_low[i] |= i2c_smbus_read_byte_data(client,
191  TMP401_TEMP_LOW_LIMIT_LSB[i]);
192  data->temp_high[i] = i2c_smbus_read_byte_data(client,
193  TMP401_TEMP_HIGH_LIMIT_MSB_READ[i]) << 8;
194  data->temp_high[i] |= i2c_smbus_read_byte_data(client,
195  TMP401_TEMP_HIGH_LIMIT_LSB[i]);
196  data->temp_crit[i] = i2c_smbus_read_byte_data(client,
197  TMP401_TEMP_CRIT_LIMIT[i]);
198 
199  if (data->kind == tmp411) {
200  data->temp_lowest[i] = i2c_smbus_read_byte_data(client,
201  TMP411_TEMP_LOWEST_MSB[i]) << 8;
203  client, TMP411_TEMP_LOWEST_LSB[i]);
204 
206  client, TMP411_TEMP_HIGHEST_MSB[i]) << 8;
208  client, TMP411_TEMP_HIGHEST_LSB[i]);
209  }
210  }
211  return data;
212 }
213 
214 static struct tmp401_data *tmp401_update_device(struct device *dev)
215 {
216  struct i2c_client *client = to_i2c_client(dev);
217  struct tmp401_data *data = i2c_get_clientdata(client);
218 
219  mutex_lock(&data->update_lock);
220 
221  if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
223  data->config = i2c_smbus_read_byte_data(client,
225  tmp401_update_device_reg16(client, data);
226 
229 
230  data->last_updated = jiffies;
231  data->valid = 1;
232  }
233 
234  mutex_unlock(&data->update_lock);
235 
236  return data;
237 }
238 
239 static ssize_t show_temp_value(struct device *dev,
240  struct device_attribute *devattr, char *buf)
241 {
242  int index = to_sensor_dev_attr(devattr)->index;
243  struct tmp401_data *data = tmp401_update_device(dev);
244 
245  return sprintf(buf, "%d\n",
246  tmp401_register_to_temp(data->temp[index], data->config));
247 }
248 
249 static ssize_t show_temp_min(struct device *dev,
250  struct device_attribute *devattr, char *buf)
251 {
252  int index = to_sensor_dev_attr(devattr)->index;
253  struct tmp401_data *data = tmp401_update_device(dev);
254 
255  return sprintf(buf, "%d\n",
256  tmp401_register_to_temp(data->temp_low[index], data->config));
257 }
258 
259 static ssize_t show_temp_max(struct device *dev,
260  struct device_attribute *devattr, char *buf)
261 {
262  int index = to_sensor_dev_attr(devattr)->index;
263  struct tmp401_data *data = tmp401_update_device(dev);
264 
265  return sprintf(buf, "%d\n",
266  tmp401_register_to_temp(data->temp_high[index], data->config));
267 }
268 
269 static ssize_t show_temp_crit(struct device *dev,
270  struct device_attribute *devattr, char *buf)
271 {
272  int index = to_sensor_dev_attr(devattr)->index;
273  struct tmp401_data *data = tmp401_update_device(dev);
274 
275  return sprintf(buf, "%d\n",
276  tmp401_crit_register_to_temp(data->temp_crit[index],
277  data->config));
278 }
279 
280 static ssize_t show_temp_crit_hyst(struct device *dev,
281  struct device_attribute *devattr, char *buf)
282 {
283  int temp, index = to_sensor_dev_attr(devattr)->index;
284  struct tmp401_data *data = tmp401_update_device(dev);
285 
286  mutex_lock(&data->update_lock);
287  temp = tmp401_crit_register_to_temp(data->temp_crit[index],
288  data->config);
289  temp -= data->temp_crit_hyst * 1000;
290  mutex_unlock(&data->update_lock);
291 
292  return sprintf(buf, "%d\n", temp);
293 }
294 
295 static ssize_t show_temp_lowest(struct device *dev,
296  struct device_attribute *devattr, char *buf)
297 {
298  int index = to_sensor_dev_attr(devattr)->index;
299  struct tmp401_data *data = tmp401_update_device(dev);
300 
301  return sprintf(buf, "%d\n",
302  tmp401_register_to_temp(data->temp_lowest[index],
303  data->config));
304 }
305 
306 static ssize_t show_temp_highest(struct device *dev,
307  struct device_attribute *devattr, char *buf)
308 {
309  int index = to_sensor_dev_attr(devattr)->index;
310  struct tmp401_data *data = tmp401_update_device(dev);
311 
312  return sprintf(buf, "%d\n",
313  tmp401_register_to_temp(data->temp_highest[index],
314  data->config));
315 }
316 
317 static ssize_t show_status(struct device *dev,
318  struct device_attribute *devattr, char *buf)
319 {
320  int mask = to_sensor_dev_attr(devattr)->index;
321  struct tmp401_data *data = tmp401_update_device(dev);
322 
323  if (data->status & mask)
324  return sprintf(buf, "1\n");
325  else
326  return sprintf(buf, "0\n");
327 }
328 
329 static ssize_t store_temp_min(struct device *dev, struct device_attribute
330  *devattr, const char *buf, size_t count)
331 {
332  int index = to_sensor_dev_attr(devattr)->index;
333  struct tmp401_data *data = tmp401_update_device(dev);
334  long val;
335  u16 reg;
336 
337  if (kstrtol(buf, 10, &val))
338  return -EINVAL;
339 
340  reg = tmp401_temp_to_register(val, data->config);
341 
342  mutex_lock(&data->update_lock);
343 
345  TMP401_TEMP_LOW_LIMIT_MSB_WRITE[index], reg >> 8);
347  TMP401_TEMP_LOW_LIMIT_LSB[index], reg & 0xFF);
348 
349  data->temp_low[index] = reg;
350 
351  mutex_unlock(&data->update_lock);
352 
353  return count;
354 }
355 
356 static ssize_t store_temp_max(struct device *dev, struct device_attribute
357  *devattr, const char *buf, size_t count)
358 {
359  int index = to_sensor_dev_attr(devattr)->index;
360  struct tmp401_data *data = tmp401_update_device(dev);
361  long val;
362  u16 reg;
363 
364  if (kstrtol(buf, 10, &val))
365  return -EINVAL;
366 
367  reg = tmp401_temp_to_register(val, data->config);
368 
369  mutex_lock(&data->update_lock);
370 
372  TMP401_TEMP_HIGH_LIMIT_MSB_WRITE[index], reg >> 8);
374  TMP401_TEMP_HIGH_LIMIT_LSB[index], reg & 0xFF);
375 
376  data->temp_high[index] = reg;
377 
378  mutex_unlock(&data->update_lock);
379 
380  return count;
381 }
382 
383 static ssize_t store_temp_crit(struct device *dev, struct device_attribute
384  *devattr, const char *buf, size_t count)
385 {
386  int index = to_sensor_dev_attr(devattr)->index;
387  struct tmp401_data *data = tmp401_update_device(dev);
388  long val;
389  u8 reg;
390 
391  if (kstrtol(buf, 10, &val))
392  return -EINVAL;
393 
394  reg = tmp401_crit_temp_to_register(val, data->config);
395 
396  mutex_lock(&data->update_lock);
397 
399  TMP401_TEMP_CRIT_LIMIT[index], reg);
400 
401  data->temp_crit[index] = reg;
402 
403  mutex_unlock(&data->update_lock);
404 
405  return count;
406 }
407 
408 static ssize_t store_temp_crit_hyst(struct device *dev, struct device_attribute
409  *devattr, const char *buf, size_t count)
410 {
411  int temp, index = to_sensor_dev_attr(devattr)->index;
412  struct tmp401_data *data = tmp401_update_device(dev);
413  long val;
414  u8 reg;
415 
416  if (kstrtol(buf, 10, &val))
417  return -EINVAL;
418 
419  if (data->config & TMP401_CONFIG_RANGE)
420  val = SENSORS_LIMIT(val, -64000, 191000);
421  else
422  val = SENSORS_LIMIT(val, 0, 127000);
423 
424  mutex_lock(&data->update_lock);
425  temp = tmp401_crit_register_to_temp(data->temp_crit[index],
426  data->config);
427  val = SENSORS_LIMIT(val, temp - 255000, temp);
428  reg = ((temp - val) + 500) / 1000;
429 
431  TMP401_TEMP_CRIT_HYST, reg);
432 
433  data->temp_crit_hyst = reg;
434 
435  mutex_unlock(&data->update_lock);
436 
437  return count;
438 }
439 
440 /*
441  * Resets the historical measurements of minimum and maximum temperatures.
442  * This is done by writing any value to any of the minimum/maximum registers
443  * (0x30-0x37).
444  */
445 static ssize_t reset_temp_history(struct device *dev,
446  struct device_attribute *devattr, const char *buf, size_t count)
447 {
448  long val;
449 
450  if (kstrtol(buf, 10, &val))
451  return -EINVAL;
452 
453  if (val != 1) {
454  dev_err(dev, "temp_reset_history value %ld not"
455  " supported. Use 1 to reset the history!\n", val);
456  return -EINVAL;
457  }
459  TMP411_TEMP_LOWEST_MSB[0], val);
460 
461  return count;
462 }
463 
464 static struct sensor_device_attribute tmp401_attr[] = {
465  SENSOR_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0),
466  SENSOR_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_min,
467  store_temp_min, 0),
468  SENSOR_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
469  store_temp_max, 0),
470  SENSOR_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit,
471  store_temp_crit, 0),
472  SENSOR_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_crit_hyst,
473  store_temp_crit_hyst, 0),
474  SENSOR_ATTR(temp1_min_alarm, S_IRUGO, show_status, NULL,
476  SENSOR_ATTR(temp1_max_alarm, S_IRUGO, show_status, NULL,
478  SENSOR_ATTR(temp1_crit_alarm, S_IRUGO, show_status, NULL,
480  SENSOR_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1),
481  SENSOR_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_min,
482  store_temp_min, 1),
483  SENSOR_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
484  store_temp_max, 1),
485  SENSOR_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit,
486  store_temp_crit, 1),
487  SENSOR_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_crit_hyst, NULL, 1),
488  SENSOR_ATTR(temp2_fault, S_IRUGO, show_status, NULL,
490  SENSOR_ATTR(temp2_min_alarm, S_IRUGO, show_status, NULL,
492  SENSOR_ATTR(temp2_max_alarm, S_IRUGO, show_status, NULL,
494  SENSOR_ATTR(temp2_crit_alarm, S_IRUGO, show_status, NULL,
496 };
497 
498 /*
499  * Additional features of the TMP411 chip.
500  * The TMP411 stores the minimum and maximum
501  * temperature measured since power-on, chip-reset, or
502  * minimum and maximum register reset for both the local
503  * and remote channels.
504  */
505 static struct sensor_device_attribute tmp411_attr[] = {
506  SENSOR_ATTR(temp1_highest, S_IRUGO, show_temp_highest, NULL, 0),
507  SENSOR_ATTR(temp1_lowest, S_IRUGO, show_temp_lowest, NULL, 0),
508  SENSOR_ATTR(temp2_highest, S_IRUGO, show_temp_highest, NULL, 1),
509  SENSOR_ATTR(temp2_lowest, S_IRUGO, show_temp_lowest, NULL, 1),
510  SENSOR_ATTR(temp_reset_history, S_IWUSR, NULL, reset_temp_history, 0),
511 };
512 
513 /*
514  * Begin non sysfs callback code (aka Real code)
515  */
516 
517 static void tmp401_init_client(struct i2c_client *client)
518 {
519  int config, config_orig;
520 
521  /* Set the conversion rate to 2 Hz */
523 
524  /* Start conversions (disable shutdown if necessary) */
526  if (config < 0) {
527  dev_warn(&client->dev, "Initialization failed!\n");
528  return;
529  }
530 
531  config_orig = config;
532  config &= ~TMP401_CONFIG_SHUTDOWN;
533 
534  if (config != config_orig)
536 }
537 
538 static int tmp401_detect(struct i2c_client *client,
539  struct i2c_board_info *info)
540 {
541  enum chips kind;
542  struct i2c_adapter *adapter = client->adapter;
543  u8 reg;
544 
545  if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
546  return -ENODEV;
547 
548  /* Detect and identify the chip */
550  if (reg != TMP401_MANUFACTURER_ID)
551  return -ENODEV;
552 
554 
555  switch (reg) {
556  case TMP401_DEVICE_ID:
557  kind = tmp401;
558  break;
559  case TMP411_DEVICE_ID:
560  kind = tmp411;
561  break;
562  default:
563  return -ENODEV;
564  }
565 
567  if (reg & 0x1b)
568  return -ENODEV;
569 
571  /* Datasheet says: 0x1-0x6 */
572  if (reg > 15)
573  return -ENODEV;
574 
575  strlcpy(info->type, tmp401_id[kind].name, I2C_NAME_SIZE);
576 
577  return 0;
578 }
579 
580 static int tmp401_remove(struct i2c_client *client)
581 {
582  struct tmp401_data *data = i2c_get_clientdata(client);
583  int i;
584 
585  if (data->hwmon_dev)
587 
588  for (i = 0; i < ARRAY_SIZE(tmp401_attr); i++)
589  device_remove_file(&client->dev, &tmp401_attr[i].dev_attr);
590 
591  if (data->kind == tmp411) {
592  for (i = 0; i < ARRAY_SIZE(tmp411_attr); i++)
593  device_remove_file(&client->dev,
594  &tmp411_attr[i].dev_attr);
595  }
596 
597  return 0;
598 }
599 
600 static int tmp401_probe(struct i2c_client *client,
601  const struct i2c_device_id *id)
602 {
603  int i, err = 0;
604  struct tmp401_data *data;
605  const char *names[] = { "TMP401", "TMP411" };
606 
607  data = devm_kzalloc(&client->dev, sizeof(struct tmp401_data),
608  GFP_KERNEL);
609  if (!data)
610  return -ENOMEM;
611 
612  i2c_set_clientdata(client, data);
613  mutex_init(&data->update_lock);
614  data->kind = id->driver_data;
615 
616  /* Initialize the TMP401 chip */
617  tmp401_init_client(client);
618 
619  /* Register sysfs hooks */
620  for (i = 0; i < ARRAY_SIZE(tmp401_attr); i++) {
621  err = device_create_file(&client->dev,
622  &tmp401_attr[i].dev_attr);
623  if (err)
624  goto exit_remove;
625  }
626 
627  /* Register additional tmp411 sysfs hooks */
628  if (data->kind == tmp411) {
629  for (i = 0; i < ARRAY_SIZE(tmp411_attr); i++) {
630  err = device_create_file(&client->dev,
631  &tmp411_attr[i].dev_attr);
632  if (err)
633  goto exit_remove;
634  }
635  }
636 
637  data->hwmon_dev = hwmon_device_register(&client->dev);
638  if (IS_ERR(data->hwmon_dev)) {
639  err = PTR_ERR(data->hwmon_dev);
640  data->hwmon_dev = NULL;
641  goto exit_remove;
642  }
643 
644  dev_info(&client->dev, "Detected TI %s chip\n", names[data->kind]);
645 
646  return 0;
647 
648 exit_remove:
649  tmp401_remove(client);
650  return err;
651 }
652 
653 static struct i2c_driver tmp401_driver = {
654  .class = I2C_CLASS_HWMON,
655  .driver = {
656  .name = "tmp401",
657  },
658  .probe = tmp401_probe,
659  .remove = tmp401_remove,
660  .id_table = tmp401_id,
661  .detect = tmp401_detect,
662  .address_list = normal_i2c,
663 };
664 
665 module_i2c_driver(tmp401_driver);
666 
667 MODULE_AUTHOR("Hans de Goede <[email protected]>");
668 MODULE_DESCRIPTION("Texas Instruments TMP401 temperature sensor driver");
669 MODULE_LICENSE("GPL");