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, MAX6658 and MAX6659 sensor
39 * chips made by Maxim. These chips are similar to the LM86. Complete
40 * datasheet 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 easy way to differenciate between the three
43 * variants. The extra address and features of the MAX6659 are not
44 * supported by this driver.
46 * Since the LM90 was the first chipset supported by this driver, most
47 * comments will refer to this chipset, but are actually general and
48 * concern all supported chipsets, unless mentioned otherwise.
50 * This program is free software; you can redistribute it and/or modify
51 * it under the terms of the GNU General Public License as published by
52 * the Free Software Foundation; either version 2 of the License, or
53 * (at your option) any later version.
55 * This program is distributed in the hope that it will be useful,
56 * but WITHOUT ANY WARRANTY; without even the implied warranty of
57 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
58 * GNU General Public License for more details.
60 * You should have received a copy of the GNU General Public License
61 * along with this program; if not, write to the Free Software
62 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
65 #include <linux/config.h>
66 #include <linux/module.h>
67 #include <linux/init.h>
68 #include <linux/slab.h>
69 #include <linux/i2c.h>
70 #include <linux/i2c-sensor.h>
74 * Address is fully defined internally and cannot be changed except for
76 * LM86, LM89, LM90, LM99, ADM1032, MAX6657 and MAX6658 have address 0x4c.
77 * LM89-1, and LM99-1 have address 0x4d.
78 * MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported).
81 static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
82 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
88 SENSORS_INSMOD_5(lm90, adm1032, lm99, lm86, max6657);
94 #define LM90_REG_R_MAN_ID 0xFE
95 #define LM90_REG_R_CHIP_ID 0xFF
96 #define LM90_REG_R_CONFIG1 0x03
97 #define LM90_REG_W_CONFIG1 0x09
98 #define LM90_REG_R_CONFIG2 0xBF
99 #define LM90_REG_W_CONFIG2 0xBF
100 #define LM90_REG_R_CONVRATE 0x04
101 #define LM90_REG_W_CONVRATE 0x0A
102 #define LM90_REG_R_STATUS 0x02
103 #define LM90_REG_R_LOCAL_TEMP 0x00
104 #define LM90_REG_R_LOCAL_HIGH 0x05
105 #define LM90_REG_W_LOCAL_HIGH 0x0B
106 #define LM90_REG_R_LOCAL_LOW 0x06
107 #define LM90_REG_W_LOCAL_LOW 0x0C
108 #define LM90_REG_R_LOCAL_CRIT 0x20
109 #define LM90_REG_W_LOCAL_CRIT 0x20
110 #define LM90_REG_R_REMOTE_TEMPH 0x01
111 #define LM90_REG_R_REMOTE_TEMPL 0x10
112 #define LM90_REG_R_REMOTE_OFFSH 0x11
113 #define LM90_REG_W_REMOTE_OFFSH 0x11
114 #define LM90_REG_R_REMOTE_OFFSL 0x12
115 #define LM90_REG_W_REMOTE_OFFSL 0x12
116 #define LM90_REG_R_REMOTE_HIGHH 0x07
117 #define LM90_REG_W_REMOTE_HIGHH 0x0D
118 #define LM90_REG_R_REMOTE_HIGHL 0x13
119 #define LM90_REG_W_REMOTE_HIGHL 0x13
120 #define LM90_REG_R_REMOTE_LOWH 0x08
121 #define LM90_REG_W_REMOTE_LOWH 0x0E
122 #define LM90_REG_R_REMOTE_LOWL 0x14
123 #define LM90_REG_W_REMOTE_LOWL 0x14
124 #define LM90_REG_R_REMOTE_CRIT 0x19
125 #define LM90_REG_W_REMOTE_CRIT 0x19
126 #define LM90_REG_R_TCRIT_HYST 0x21
127 #define LM90_REG_W_TCRIT_HYST 0x21
130 * Conversions and various macros
131 * For local temperatures and limits, critical limits and the hysteresis
132 * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celcius.
133 * For remote temperatures and limits, it uses signed 11-bit values with
134 * LSB = 0.125 degree Celcius, left-justified in 16-bit registers.
137 #define TEMP1_FROM_REG(val) ((val) * 1000)
138 #define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \
139 (val) >= 127000 ? 127 : \
140 (val) < 0 ? ((val) - 500) / 1000 : \
141 ((val) + 500) / 1000)
142 #define TEMP2_FROM_REG(val) ((val) / 32 * 125)
143 #define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \
144 (val) >= 127875 ? 0x7FE0 : \
145 (val) < 0 ? ((val) - 62) / 125 * 32 : \
146 ((val) + 62) / 125 * 32)
147 #define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
148 ((val) + 500) / 1000)
151 * Functions declaration
154 static int lm90_attach_adapter(struct i2c_adapter *adapter);
155 static int lm90_detect(struct i2c_adapter *adapter, int address,
157 static void lm90_init_client(struct i2c_client *client);
158 static int lm90_detach_client(struct i2c_client *client);
159 static struct lm90_data *lm90_update_device(struct device *dev);
162 * Driver data (common to all clients)
165 static struct i2c_driver lm90_driver = {
166 .owner = THIS_MODULE,
168 .id = I2C_DRIVERID_LM90,
169 .flags = I2C_DF_NOTIFY,
170 .attach_adapter = lm90_attach_adapter,
171 .detach_client = lm90_detach_client,
175 * Client data (each client gets its own)
179 struct i2c_client client;
180 struct semaphore update_lock;
181 char valid; /* zero until following fields are valid */
182 unsigned long last_updated; /* in jiffies */
184 /* registers values */
185 s8 temp_input1, temp_low1, temp_high1; /* local */
186 s16 temp_input2, temp_low2, temp_high2; /* remote, combined */
187 s8 temp_crit1, temp_crit2;
189 u8 alarms; /* bitvector */
202 #define show_temp(value, converter) \
203 static ssize_t show_##value(struct device *dev, char *buf) \
205 struct lm90_data *data = lm90_update_device(dev); \
206 return sprintf(buf, "%d\n", converter(data->value)); \
208 show_temp(temp_input1, TEMP1_FROM_REG);
209 show_temp(temp_input2, TEMP2_FROM_REG);
210 show_temp(temp_low1, TEMP1_FROM_REG);
211 show_temp(temp_low2, TEMP2_FROM_REG);
212 show_temp(temp_high1, TEMP1_FROM_REG);
213 show_temp(temp_high2, TEMP2_FROM_REG);
214 show_temp(temp_crit1, TEMP1_FROM_REG);
215 show_temp(temp_crit2, TEMP1_FROM_REG);
217 #define set_temp1(value, reg) \
218 static ssize_t set_##value(struct device *dev, const char *buf, \
221 struct i2c_client *client = to_i2c_client(dev); \
222 struct lm90_data *data = i2c_get_clientdata(client); \
223 long val = simple_strtol(buf, NULL, 10); \
224 data->value = TEMP1_TO_REG(val); \
225 i2c_smbus_write_byte_data(client, reg, data->value); \
228 #define set_temp2(value, regh, regl) \
229 static ssize_t set_##value(struct device *dev, const char *buf, \
232 struct i2c_client *client = to_i2c_client(dev); \
233 struct lm90_data *data = i2c_get_clientdata(client); \
234 long val = simple_strtol(buf, NULL, 10); \
235 data->value = TEMP2_TO_REG(val); \
236 i2c_smbus_write_byte_data(client, regh, data->value >> 8); \
237 i2c_smbus_write_byte_data(client, regl, data->value & 0xff); \
240 set_temp1(temp_low1, LM90_REG_W_LOCAL_LOW);
241 set_temp2(temp_low2, LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL);
242 set_temp1(temp_high1, LM90_REG_W_LOCAL_HIGH);
243 set_temp2(temp_high2, LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL);
244 set_temp1(temp_crit1, LM90_REG_W_LOCAL_CRIT);
245 set_temp1(temp_crit2, LM90_REG_W_REMOTE_CRIT);
247 #define show_temp_hyst(value, basereg) \
248 static ssize_t show_##value(struct device *dev, char *buf) \
250 struct lm90_data *data = lm90_update_device(dev); \
251 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->basereg) \
252 - TEMP1_FROM_REG(data->temp_hyst)); \
254 show_temp_hyst(temp_hyst1, temp_crit1);
255 show_temp_hyst(temp_hyst2, temp_crit2);
257 static ssize_t set_temp_hyst1(struct device *dev, const char *buf,
260 struct i2c_client *client = to_i2c_client(dev);
261 struct lm90_data *data = i2c_get_clientdata(client);
262 int hyst = TEMP1_FROM_REG(data->temp_crit1) -
263 simple_strtol(buf, NULL, 10);
264 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
269 static ssize_t show_alarms(struct device *dev, char *buf)
271 struct lm90_data *data = lm90_update_device(dev);
272 return sprintf(buf, "%d\n", data->alarms);
275 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
276 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
277 static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_low1,
279 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
281 static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_high1,
283 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
285 static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit1,
287 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
289 static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst1,
291 static DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_hyst2, NULL);
292 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
298 static int lm90_attach_adapter(struct i2c_adapter *adapter)
300 if (!(adapter->class & I2C_CLASS_HWMON))
302 return i2c_detect(adapter, &addr_data, lm90_detect);
306 * The following function does more than just detection. If detection
307 * succeeds, it also registers the new chip.
309 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
311 struct i2c_client *new_client;
312 struct lm90_data *data;
314 const char *name = "";
316 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
319 if (!(data = kmalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
323 memset(data, 0, sizeof(struct lm90_data));
325 /* The common I2C client data is placed right before the
326 LM90-specific data. */
327 new_client = &data->client;
328 i2c_set_clientdata(new_client, data);
329 new_client->addr = address;
330 new_client->adapter = adapter;
331 new_client->driver = &lm90_driver;
332 new_client->flags = 0;
335 * Now we do the remaining detection. A negative kind means that
336 * the driver was loaded with no force parameter (default), so we
337 * must both detect and identify the chip. A zero kind means that
338 * the driver was loaded with the force parameter, the detection
339 * step shall be skipped. A positive kind means that the driver
340 * was loaded with the force parameter and a given kind of chip is
341 * requested, so both the detection and the identification steps
345 /* Default to an LM90 if forced */
349 if (kind < 0) { /* detection and identification */
350 u8 man_id, chip_id, reg_config1, reg_convrate;
352 man_id = i2c_smbus_read_byte_data(new_client,
354 chip_id = i2c_smbus_read_byte_data(new_client,
356 reg_config1 = i2c_smbus_read_byte_data(new_client,
358 reg_convrate = i2c_smbus_read_byte_data(new_client,
359 LM90_REG_R_CONVRATE);
361 if (man_id == 0x01) { /* National Semiconductor */
364 reg_config2 = i2c_smbus_read_byte_data(new_client,
367 if ((reg_config1 & 0x2A) == 0x00
368 && (reg_config2 & 0xF8) == 0x00
369 && reg_convrate <= 0x09) {
371 && (chip_id & 0xF0) == 0x20) { /* LM90 */
374 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
378 && (chip_id & 0xF0) == 0x10) { /* LM86 */
383 if (man_id == 0x41) { /* Analog Devices */
385 && (chip_id & 0xF0) == 0x40 /* ADM1032 */
386 && (reg_config1 & 0x3F) == 0x00
387 && reg_convrate <= 0x0A) {
391 if (man_id == 0x4D) { /* Maxim */
393 * The Maxim variants do NOT have a chip_id register.
394 * Reading from that address will return the last read
395 * value, which in our case is those of the man_id
396 * register. Likewise, the config1 register seems to
397 * lack a low nibble, so the value will be those of the
398 * previous read, so in our case those of the man_id
401 if (chip_id == man_id
402 && (reg_config1 & 0x1F) == (man_id & 0x0F)
403 && reg_convrate <= 0x09) {
408 if (kind <= 0) { /* identification failed */
409 dev_info(&adapter->dev,
410 "Unsupported chip (man_id=0x%02X, "
411 "chip_id=0x%02X).\n", man_id, chip_id);
418 } else if (kind == adm1032) {
420 } else if (kind == lm99) {
422 } else if (kind == lm86) {
424 } else if (kind == max6657) {
428 /* We can fill in the remaining client fields */
429 strlcpy(new_client->name, name, I2C_NAME_SIZE);
430 new_client->id = lm90_id++;
432 init_MUTEX(&data->update_lock);
434 /* Tell the I2C layer a new client has arrived */
435 if ((err = i2c_attach_client(new_client)))
438 /* Initialize the LM90 chip */
439 lm90_init_client(new_client);
441 /* Register sysfs hooks */
442 device_create_file(&new_client->dev, &dev_attr_temp1_input);
443 device_create_file(&new_client->dev, &dev_attr_temp2_input);
444 device_create_file(&new_client->dev, &dev_attr_temp1_min);
445 device_create_file(&new_client->dev, &dev_attr_temp2_min);
446 device_create_file(&new_client->dev, &dev_attr_temp1_max);
447 device_create_file(&new_client->dev, &dev_attr_temp2_max);
448 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
449 device_create_file(&new_client->dev, &dev_attr_temp2_crit);
450 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
451 device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
452 device_create_file(&new_client->dev, &dev_attr_alarms);
462 static void lm90_init_client(struct i2c_client *client)
467 * Start the conversions.
469 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
471 config = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
473 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
474 config & 0xBF); /* run */
477 static int lm90_detach_client(struct i2c_client *client)
481 if ((err = i2c_detach_client(client))) {
482 dev_err(&client->dev, "Client deregistration failed, "
483 "client not detached.\n");
487 kfree(i2c_get_clientdata(client));
491 static struct lm90_data *lm90_update_device(struct device *dev)
493 struct i2c_client *client = to_i2c_client(dev);
494 struct lm90_data *data = i2c_get_clientdata(client);
496 down(&data->update_lock);
498 if ((jiffies - data->last_updated > HZ * 2) ||
499 (jiffies < data->last_updated) ||
503 dev_dbg(&client->dev, "Updating lm90 data.\n");
504 data->temp_input1 = i2c_smbus_read_byte_data(client,
505 LM90_REG_R_LOCAL_TEMP);
506 data->temp_high1 = i2c_smbus_read_byte_data(client,
507 LM90_REG_R_LOCAL_HIGH);
508 data->temp_low1 = i2c_smbus_read_byte_data(client,
509 LM90_REG_R_LOCAL_LOW);
510 data->temp_crit1 = i2c_smbus_read_byte_data(client,
511 LM90_REG_R_LOCAL_CRIT);
512 data->temp_crit2 = i2c_smbus_read_byte_data(client,
513 LM90_REG_R_REMOTE_CRIT);
514 data->temp_hyst = i2c_smbus_read_byte_data(client,
515 LM90_REG_R_TCRIT_HYST);
518 * There is a trick here. We have to read two registers to
519 * have the remote sensor temperature, but we have to beware
520 * a conversion could occur inbetween the readings. The
521 * datasheet says we should either use the one-shot
522 * conversion register, which we don't want to do (disables
523 * hardware monitoring) or monitor the busy bit, which is
524 * impossible (we can't read the values and monitor that bit
525 * at the exact same time). So the solution used here is to
526 * read the high byte once, then the low byte, then the high
527 * byte again. If the new high byte matches the old one,
528 * then we have a valid reading. Else we have to read the low
529 * byte again, and now we believe we have a correct reading.
531 oldh = i2c_smbus_read_byte_data(client,
532 LM90_REG_R_REMOTE_TEMPH);
533 data->temp_input2 = i2c_smbus_read_byte_data(client,
534 LM90_REG_R_REMOTE_TEMPL);
535 newh = i2c_smbus_read_byte_data(client,
536 LM90_REG_R_REMOTE_TEMPH);
538 data->temp_input2 = i2c_smbus_read_byte_data(client,
539 LM90_REG_R_REMOTE_TEMPL);
541 oldh = i2c_smbus_read_byte_data(client,
542 LM90_REG_R_REMOTE_TEMPH);
543 /* oldh is actually newer */
545 dev_warn(&client->dev, "Remote temperature may be "
549 data->temp_input2 |= (newh << 8);
551 data->temp_high2 = (i2c_smbus_read_byte_data(client,
552 LM90_REG_R_REMOTE_HIGHH) << 8) +
553 i2c_smbus_read_byte_data(client,
554 LM90_REG_R_REMOTE_HIGHL);
555 data->temp_low2 = (i2c_smbus_read_byte_data(client,
556 LM90_REG_R_REMOTE_LOWH) << 8) +
557 i2c_smbus_read_byte_data(client,
558 LM90_REG_R_REMOTE_LOWL);
559 data->alarms = i2c_smbus_read_byte_data(client,
562 data->last_updated = jiffies;
566 up(&data->update_lock);
571 static int __init sensors_lm90_init(void)
573 return i2c_add_driver(&lm90_driver);
576 static void __exit sensors_lm90_exit(void)
578 i2c_del_driver(&lm90_driver);
581 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
582 MODULE_DESCRIPTION("LM90/ADM1032 driver");
583 MODULE_LICENSE("GPL");
585 module_init(sensors_lm90_init);
586 module_exit(sensors_lm90_exit);