2 * lm90.c - Part of lm_sensors, Linux kernel modules for hardware
4 * Copyright (C) 2003-2004 Jean Delvare <khali@linux-fr.org>
6 * Based on the lm83 driver. The LM90 is a sensor chip made by National
7 * Semiconductor. It reports up to two temperatures (its own plus up to
8 * one external one) with a 0.125 deg resolution (1 deg for local
9 * temperature) and a 3-4 deg accuracy. Complete datasheet can be
10 * obtained from National's website at:
11 * http://www.national.com/pf/LM/LM90.html
13 * This driver also supports the LM89 and LM99, two other sensor chips
14 * made by National Semiconductor. Both have an increased remote
15 * temperature measurement accuracy (1 degree), and the LM99
16 * additionally shifts remote temperatures (measured and limits) by 16
17 * degrees, which allows for higher temperatures measurement. The
18 * driver doesn't handle it since it can be done easily in user-space.
19 * Complete datasheets can be obtained from National's website at:
20 * http://www.national.com/pf/LM/LM89.html
21 * http://www.national.com/pf/LM/LM99.html
22 * Note that there is no way to differenciate between both chips.
24 * This driver also supports the LM86, another sensor chip made by
25 * National Semiconductor. It is exactly similar to the LM90 except it
26 * has a higher accuracy.
27 * Complete datasheet can be obtained from National's website at:
28 * http://www.national.com/pf/LM/LM86.html
30 * This driver also supports the ADM1032, a sensor chip made by Analog
31 * Devices. That chip is similar to the LM90, with a few differences
32 * that are not handled by this driver. Complete datasheet can be
33 * obtained from Analog's website at:
34 * http://products.analog.com/products/info.asp?product=ADM1032
35 * Among others, it has a higher accuracy than the LM90, much like the
38 * This driver also supports the MAX6657 and MAX6658, sensor chips made
39 * by Maxim. These chips are similar to the LM86. Complete datasheet
40 * can be obtained at Maxim's website at:
41 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
42 * Note that there is no way to differenciate between both chips (but
45 * Since the LM90 was the first chipset supported by this driver, most
46 * comments will refer to this chipset, but are actually general and
47 * concern all supported chipsets, unless mentioned otherwise.
49 * This program is free software; you can redistribute it and/or modify
50 * it under the terms of the GNU General Public License as published by
51 * the Free Software Foundation; either version 2 of the License, or
52 * (at your option) any later version.
54 * This program is distributed in the hope that it will be useful,
55 * but WITHOUT ANY WARRANTY; without even the implied warranty of
56 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
57 * GNU General Public License for more details.
59 * You should have received a copy of the GNU General Public License
60 * along with this program; if not, write to the Free Software
61 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
64 #include <linux/config.h>
65 #include <linux/module.h>
66 #include <linux/init.h>
67 #include <linux/slab.h>
68 #include <linux/i2c.h>
69 #include <linux/i2c-sensor.h>
73 * Address is fully defined internally and cannot be changed.
74 * LM86, LM89, LM90, LM99, ADM1032, MAX6657 and MAX6658 have address 0x4c.
75 * LM89-1, and LM99-1 have address 0x4d.
78 static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
79 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
85 SENSORS_INSMOD_5(lm90, adm1032, lm99, lm86, max6657);
91 #define LM90_REG_R_MAN_ID 0xFE
92 #define LM90_REG_R_CHIP_ID 0xFF
93 #define LM90_REG_R_CONFIG1 0x03
94 #define LM90_REG_W_CONFIG1 0x09
95 #define LM90_REG_R_CONFIG2 0xBF
96 #define LM90_REG_W_CONFIG2 0xBF
97 #define LM90_REG_R_CONVRATE 0x04
98 #define LM90_REG_W_CONVRATE 0x0A
99 #define LM90_REG_R_STATUS 0x02
100 #define LM90_REG_R_LOCAL_TEMP 0x00
101 #define LM90_REG_R_LOCAL_HIGH 0x05
102 #define LM90_REG_W_LOCAL_HIGH 0x0B
103 #define LM90_REG_R_LOCAL_LOW 0x06
104 #define LM90_REG_W_LOCAL_LOW 0x0C
105 #define LM90_REG_R_LOCAL_CRIT 0x20
106 #define LM90_REG_W_LOCAL_CRIT 0x20
107 #define LM90_REG_R_REMOTE_TEMPH 0x01
108 #define LM90_REG_R_REMOTE_TEMPL 0x10
109 #define LM90_REG_R_REMOTE_OFFSH 0x11
110 #define LM90_REG_W_REMOTE_OFFSH 0x11
111 #define LM90_REG_R_REMOTE_OFFSL 0x12
112 #define LM90_REG_W_REMOTE_OFFSL 0x12
113 #define LM90_REG_R_REMOTE_HIGHH 0x07
114 #define LM90_REG_W_REMOTE_HIGHH 0x0D
115 #define LM90_REG_R_REMOTE_HIGHL 0x13
116 #define LM90_REG_W_REMOTE_HIGHL 0x13
117 #define LM90_REG_R_REMOTE_LOWH 0x08
118 #define LM90_REG_W_REMOTE_LOWH 0x0E
119 #define LM90_REG_R_REMOTE_LOWL 0x14
120 #define LM90_REG_W_REMOTE_LOWL 0x14
121 #define LM90_REG_R_REMOTE_CRIT 0x19
122 #define LM90_REG_W_REMOTE_CRIT 0x19
123 #define LM90_REG_R_TCRIT_HYST 0x21
124 #define LM90_REG_W_TCRIT_HYST 0x21
127 * Conversions and various macros
128 * For local temperatures and limits, critical limits and the hysteresis
129 * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celcius.
130 * For remote temperatures and limits, it uses signed 11-bit values with
131 * LSB = 0.125 degree Celcius, left-justified in 16-bit registers.
134 #define TEMP1_FROM_REG(val) ((val) * 1000)
135 #define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \
136 (val) >= 127000 ? 127 : \
137 (val) < 0 ? ((val) - 500) / 1000 : \
138 ((val) + 500) / 1000)
139 #define TEMP2_FROM_REG(val) ((val) / 32 * 125)
140 #define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \
141 (val) >= 127875 ? 0x7FE0 : \
142 (val) < 0 ? ((val) - 62) / 125 * 32 : \
143 ((val) + 62) / 125 * 32)
144 #define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
145 ((val) + 500) / 1000)
148 * Functions declaration
151 static int lm90_attach_adapter(struct i2c_adapter *adapter);
152 static int lm90_detect(struct i2c_adapter *adapter, int address,
154 static void lm90_init_client(struct i2c_client *client);
155 static int lm90_detach_client(struct i2c_client *client);
156 static struct lm90_data *lm90_update_device(struct device *dev);
159 * Driver data (common to all clients)
162 static struct i2c_driver lm90_driver = {
163 .owner = THIS_MODULE,
165 .id = I2C_DRIVERID_LM90,
166 .flags = I2C_DF_NOTIFY,
167 .attach_adapter = lm90_attach_adapter,
168 .detach_client = lm90_detach_client,
172 * Client data (each client gets its own)
176 struct i2c_client client;
177 struct semaphore update_lock;
178 char valid; /* zero until following fields are valid */
179 unsigned long last_updated; /* in jiffies */
181 /* registers values */
182 s8 temp_input1, temp_low1, temp_high1; /* local */
183 s16 temp_input2, temp_low2, temp_high2; /* remote, combined */
184 s8 temp_crit1, temp_crit2;
186 u8 alarms; /* bitvector */
199 #define show_temp(value, converter) \
200 static ssize_t show_##value(struct device *dev, char *buf) \
202 struct lm90_data *data = lm90_update_device(dev); \
203 return sprintf(buf, "%d\n", converter(data->value)); \
205 show_temp(temp_input1, TEMP1_FROM_REG);
206 show_temp(temp_input2, TEMP2_FROM_REG);
207 show_temp(temp_low1, TEMP1_FROM_REG);
208 show_temp(temp_low2, TEMP2_FROM_REG);
209 show_temp(temp_high1, TEMP1_FROM_REG);
210 show_temp(temp_high2, TEMP2_FROM_REG);
211 show_temp(temp_crit1, TEMP1_FROM_REG);
212 show_temp(temp_crit2, TEMP1_FROM_REG);
214 #define set_temp1(value, reg) \
215 static ssize_t set_##value(struct device *dev, const char *buf, \
218 struct i2c_client *client = to_i2c_client(dev); \
219 struct lm90_data *data = i2c_get_clientdata(client); \
220 long val = simple_strtol(buf, NULL, 10); \
221 data->value = TEMP1_TO_REG(val); \
222 i2c_smbus_write_byte_data(client, reg, data->value); \
225 #define set_temp2(value, regh, regl) \
226 static ssize_t set_##value(struct device *dev, const char *buf, \
229 struct i2c_client *client = to_i2c_client(dev); \
230 struct lm90_data *data = i2c_get_clientdata(client); \
231 long val = simple_strtol(buf, NULL, 10); \
232 data->value = TEMP2_TO_REG(val); \
233 i2c_smbus_write_byte_data(client, regh, data->value >> 8); \
234 i2c_smbus_write_byte_data(client, regl, data->value & 0xff); \
237 set_temp1(temp_low1, LM90_REG_W_LOCAL_LOW);
238 set_temp2(temp_low2, LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL);
239 set_temp1(temp_high1, LM90_REG_W_LOCAL_HIGH);
240 set_temp2(temp_high2, LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL);
241 set_temp1(temp_crit1, LM90_REG_W_LOCAL_CRIT);
242 set_temp1(temp_crit2, LM90_REG_W_REMOTE_CRIT);
244 #define show_temp_hyst(value, basereg) \
245 static ssize_t show_##value(struct device *dev, char *buf) \
247 struct lm90_data *data = lm90_update_device(dev); \
248 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->basereg) \
249 - TEMP1_FROM_REG(data->temp_hyst)); \
251 show_temp_hyst(temp_hyst1, temp_crit1);
252 show_temp_hyst(temp_hyst2, temp_crit2);
254 static ssize_t set_temp_hyst1(struct device *dev, const char *buf,
257 struct i2c_client *client = to_i2c_client(dev);
258 struct lm90_data *data = i2c_get_clientdata(client);
259 int hyst = TEMP1_FROM_REG(data->temp_crit1) -
260 simple_strtol(buf, NULL, 10);
261 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
266 static ssize_t show_alarms(struct device *dev, char *buf)
268 struct lm90_data *data = lm90_update_device(dev);
269 return sprintf(buf, "%d\n", data->alarms);
272 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
273 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
274 static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_low1,
276 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
278 static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_high1,
280 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
282 static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit1,
284 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
286 static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst1,
288 static DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_hyst2, NULL);
289 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
295 static int lm90_attach_adapter(struct i2c_adapter *adapter)
297 if (!(adapter->class & I2C_CLASS_HWMON))
299 return i2c_detect(adapter, &addr_data, lm90_detect);
303 * The following function does more than just detection. If detection
304 * succeeds, it also registers the new chip.
306 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
308 struct i2c_client *new_client;
309 struct lm90_data *data;
311 const char *name = "";
313 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
316 if (!(data = kmalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
320 memset(data, 0, sizeof(struct lm90_data));
322 /* The common I2C client data is placed right before the
323 LM90-specific data. */
324 new_client = &data->client;
325 i2c_set_clientdata(new_client, data);
326 new_client->addr = address;
327 new_client->adapter = adapter;
328 new_client->driver = &lm90_driver;
329 new_client->flags = 0;
332 * Now we do the remaining detection. A negative kind means that
333 * the driver was loaded with no force parameter (default), so we
334 * must both detect and identify the chip. A zero kind means that
335 * the driver was loaded with the force parameter, the detection
336 * step shall be skipped. A positive kind means that the driver
337 * was loaded with the force parameter and a given kind of chip is
338 * requested, so both the detection and the identification steps
342 /* Default to an LM90 if forced */
346 if (kind < 0) { /* detection and identification */
347 u8 man_id, chip_id, reg_config1, reg_convrate;
349 man_id = i2c_smbus_read_byte_data(new_client,
351 chip_id = i2c_smbus_read_byte_data(new_client,
353 reg_config1 = i2c_smbus_read_byte_data(new_client,
355 reg_convrate = i2c_smbus_read_byte_data(new_client,
356 LM90_REG_R_CONVRATE);
358 if (man_id == 0x01) { /* National Semiconductor */
361 reg_config2 = i2c_smbus_read_byte_data(new_client,
364 if ((reg_config1 & 0x2A) == 0x00
365 && (reg_config2 & 0xF8) == 0x00
366 && reg_convrate <= 0x09) {
368 && (chip_id & 0xF0) == 0x20) { /* LM90 */
371 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
375 && (chip_id & 0xF0) == 0x10) { /* LM86 */
380 if (man_id == 0x41) { /* Analog Devices */
382 && (chip_id & 0xF0) == 0x40 /* ADM1032 */
383 && (reg_config1 & 0x3F) == 0x00
384 && reg_convrate <= 0x0A) {
388 if (man_id == 0x4D) { /* Maxim */
390 && (reg_config1 & 0x1F) == 0
391 && reg_convrate <= 0x09) {
396 if (kind <= 0) { /* identification failed */
397 dev_info(&adapter->dev,
398 "Unsupported chip (man_id=0x%02X, "
399 "chip_id=0x%02X).\n", man_id, chip_id);
406 } else if (kind == adm1032) {
408 } else if (kind == lm99) {
410 } else if (kind == lm86) {
412 } else if (kind == max6657) {
416 /* We can fill in the remaining client fields */
417 strlcpy(new_client->name, name, I2C_NAME_SIZE);
418 new_client->id = lm90_id++;
420 init_MUTEX(&data->update_lock);
422 /* Tell the I2C layer a new client has arrived */
423 if ((err = i2c_attach_client(new_client)))
426 /* Initialize the LM90 chip */
427 lm90_init_client(new_client);
429 /* Register sysfs hooks */
430 device_create_file(&new_client->dev, &dev_attr_temp1_input);
431 device_create_file(&new_client->dev, &dev_attr_temp2_input);
432 device_create_file(&new_client->dev, &dev_attr_temp1_min);
433 device_create_file(&new_client->dev, &dev_attr_temp2_min);
434 device_create_file(&new_client->dev, &dev_attr_temp1_max);
435 device_create_file(&new_client->dev, &dev_attr_temp2_max);
436 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
437 device_create_file(&new_client->dev, &dev_attr_temp2_crit);
438 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
439 device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
440 device_create_file(&new_client->dev, &dev_attr_alarms);
450 static void lm90_init_client(struct i2c_client *client)
455 * Start the conversions.
457 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
459 config = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
461 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
462 config & 0xBF); /* run */
465 static int lm90_detach_client(struct i2c_client *client)
469 if ((err = i2c_detach_client(client))) {
470 dev_err(&client->dev, "Client deregistration failed, "
471 "client not detached.\n");
475 kfree(i2c_get_clientdata(client));
479 static struct lm90_data *lm90_update_device(struct device *dev)
481 struct i2c_client *client = to_i2c_client(dev);
482 struct lm90_data *data = i2c_get_clientdata(client);
484 down(&data->update_lock);
486 if ((jiffies - data->last_updated > HZ * 2) ||
487 (jiffies < data->last_updated) ||
491 dev_dbg(&client->dev, "Updating lm90 data.\n");
492 data->temp_input1 = i2c_smbus_read_byte_data(client,
493 LM90_REG_R_LOCAL_TEMP);
494 data->temp_high1 = i2c_smbus_read_byte_data(client,
495 LM90_REG_R_LOCAL_HIGH);
496 data->temp_low1 = i2c_smbus_read_byte_data(client,
497 LM90_REG_R_LOCAL_LOW);
498 data->temp_crit1 = i2c_smbus_read_byte_data(client,
499 LM90_REG_R_LOCAL_CRIT);
500 data->temp_crit2 = i2c_smbus_read_byte_data(client,
501 LM90_REG_R_REMOTE_CRIT);
502 data->temp_hyst = i2c_smbus_read_byte_data(client,
503 LM90_REG_R_TCRIT_HYST);
506 * There is a trick here. We have to read two registers to
507 * have the remote sensor temperature, but we have to beware
508 * a conversion could occur inbetween the readings. The
509 * datasheet says we should either use the one-shot
510 * conversion register, which we don't want to do (disables
511 * hardware monitoring) or monitor the busy bit, which is
512 * impossible (we can't read the values and monitor that bit
513 * at the exact same time). So the solution used here is to
514 * read the high byte once, then the low byte, then the high
515 * byte again. If the new high byte matches the old one,
516 * then we have a valid reading. Else we have to read the low
517 * byte again, and now we believe we have a correct reading.
519 oldh = i2c_smbus_read_byte_data(client,
520 LM90_REG_R_REMOTE_TEMPH);
521 data->temp_input2 = i2c_smbus_read_byte_data(client,
522 LM90_REG_R_REMOTE_TEMPL);
523 newh = i2c_smbus_read_byte_data(client,
524 LM90_REG_R_REMOTE_TEMPH);
526 data->temp_input2 = i2c_smbus_read_byte_data(client,
527 LM90_REG_R_REMOTE_TEMPL);
529 oldh = i2c_smbus_read_byte_data(client,
530 LM90_REG_R_REMOTE_TEMPH);
531 /* oldh is actually newer */
533 dev_warn(&client->dev, "Remote temperature may be "
537 data->temp_input2 |= (newh << 8);
539 data->temp_high2 = (i2c_smbus_read_byte_data(client,
540 LM90_REG_R_REMOTE_HIGHH) << 8) +
541 i2c_smbus_read_byte_data(client,
542 LM90_REG_R_REMOTE_HIGHL);
543 data->temp_low2 = (i2c_smbus_read_byte_data(client,
544 LM90_REG_R_REMOTE_LOWH) << 8) +
545 i2c_smbus_read_byte_data(client,
546 LM90_REG_R_REMOTE_LOWL);
547 data->alarms = i2c_smbus_read_byte_data(client,
550 data->last_updated = jiffies;
554 up(&data->update_lock);
559 static int __init sensors_lm90_init(void)
561 return i2c_add_driver(&lm90_driver);
564 static void __exit sensors_lm90_exit(void)
566 i2c_del_driver(&lm90_driver);
569 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
570 MODULE_DESCRIPTION("LM90/ADM1032 driver");
571 MODULE_LICENSE("GPL");
573 module_init(sensors_lm90_init);
574 module_exit(sensors_lm90_exit);