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 differentiate 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 differentiate between the three
43 * variants. The extra address and features of the MAX6659 are not
44 * supported by this driver.
46 * This driver also supports the ADT7461 chip from Analog Devices but
47 * only in its "compatability mode". If an ADT7461 chip is found but
48 * is configured in non-compatible mode (where its temperature
49 * register values are decoded differently) it is ignored by this
50 * driver. Complete datasheet can be obtained from Analog's website
52 * http://products.analog.com/products/info.asp?product=ADT7461
54 * Since the LM90 was the first chipset supported by this driver, most
55 * comments will refer to this chipset, but are actually general and
56 * concern all supported chipsets, unless mentioned otherwise.
58 * This program is free software; you can redistribute it and/or modify
59 * it under the terms of the GNU General Public License as published by
60 * the Free Software Foundation; either version 2 of the License, or
61 * (at your option) any later version.
63 * This program is distributed in the hope that it will be useful,
64 * but WITHOUT ANY WARRANTY; without even the implied warranty of
65 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
66 * GNU General Public License for more details.
68 * You should have received a copy of the GNU General Public License
69 * along with this program; if not, write to the Free Software
70 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
73 #include <linux/module.h>
74 #include <linux/init.h>
75 #include <linux/slab.h>
76 #include <linux/jiffies.h>
77 #include <linux/i2c.h>
78 #include <linux/i2c-sensor.h>
82 * Address is fully defined internally and cannot be changed except for
84 * LM86, LM89, LM90, LM99, ADM1032, MAX6657 and MAX6658 have address 0x4c.
85 * LM89-1, and LM99-1 have address 0x4d.
86 * MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported).
87 * ADT7461 always has address 0x4c.
90 static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
91 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
97 SENSORS_INSMOD_6(lm90, adm1032, lm99, lm86, max6657, adt7461);
103 #define LM90_REG_R_MAN_ID 0xFE
104 #define LM90_REG_R_CHIP_ID 0xFF
105 #define LM90_REG_R_CONFIG1 0x03
106 #define LM90_REG_W_CONFIG1 0x09
107 #define LM90_REG_R_CONFIG2 0xBF
108 #define LM90_REG_W_CONFIG2 0xBF
109 #define LM90_REG_R_CONVRATE 0x04
110 #define LM90_REG_W_CONVRATE 0x0A
111 #define LM90_REG_R_STATUS 0x02
112 #define LM90_REG_R_LOCAL_TEMP 0x00
113 #define LM90_REG_R_LOCAL_HIGH 0x05
114 #define LM90_REG_W_LOCAL_HIGH 0x0B
115 #define LM90_REG_R_LOCAL_LOW 0x06
116 #define LM90_REG_W_LOCAL_LOW 0x0C
117 #define LM90_REG_R_LOCAL_CRIT 0x20
118 #define LM90_REG_W_LOCAL_CRIT 0x20
119 #define LM90_REG_R_REMOTE_TEMPH 0x01
120 #define LM90_REG_R_REMOTE_TEMPL 0x10
121 #define LM90_REG_R_REMOTE_OFFSH 0x11
122 #define LM90_REG_W_REMOTE_OFFSH 0x11
123 #define LM90_REG_R_REMOTE_OFFSL 0x12
124 #define LM90_REG_W_REMOTE_OFFSL 0x12
125 #define LM90_REG_R_REMOTE_HIGHH 0x07
126 #define LM90_REG_W_REMOTE_HIGHH 0x0D
127 #define LM90_REG_R_REMOTE_HIGHL 0x13
128 #define LM90_REG_W_REMOTE_HIGHL 0x13
129 #define LM90_REG_R_REMOTE_LOWH 0x08
130 #define LM90_REG_W_REMOTE_LOWH 0x0E
131 #define LM90_REG_R_REMOTE_LOWL 0x14
132 #define LM90_REG_W_REMOTE_LOWL 0x14
133 #define LM90_REG_R_REMOTE_CRIT 0x19
134 #define LM90_REG_W_REMOTE_CRIT 0x19
135 #define LM90_REG_R_TCRIT_HYST 0x21
136 #define LM90_REG_W_TCRIT_HYST 0x21
139 * Conversions and various macros
140 * For local temperatures and limits, critical limits and the hysteresis
141 * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius.
142 * For remote temperatures and limits, it uses signed 11-bit values with
143 * LSB = 0.125 degree Celsius, left-justified in 16-bit registers.
146 #define TEMP1_FROM_REG(val) ((val) * 1000)
147 #define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \
148 (val) >= 127000 ? 127 : \
149 (val) < 0 ? ((val) - 500) / 1000 : \
150 ((val) + 500) / 1000)
151 #define TEMP2_FROM_REG(val) ((val) / 32 * 125)
152 #define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \
153 (val) >= 127875 ? 0x7FE0 : \
154 (val) < 0 ? ((val) - 62) / 125 * 32 : \
155 ((val) + 62) / 125 * 32)
156 #define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
157 ((val) + 500) / 1000)
160 * ADT7461 is almost identical to LM90 except that attempts to write
161 * values that are outside the range 0 < temp < 127 are treated as
162 * the boundary value.
165 #define TEMP1_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
166 (val) >= 127000 ? 127 : \
167 ((val) + 500) / 1000)
168 #define TEMP2_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
169 (val) >= 127750 ? 0x7FC0 : \
170 ((val) + 125) / 250 * 64)
173 * Functions declaration
176 static int lm90_attach_adapter(struct i2c_adapter *adapter);
177 static int lm90_detect(struct i2c_adapter *adapter, int address,
179 static void lm90_init_client(struct i2c_client *client);
180 static int lm90_detach_client(struct i2c_client *client);
181 static struct lm90_data *lm90_update_device(struct device *dev);
184 * Driver data (common to all clients)
187 static struct i2c_driver lm90_driver = {
188 .owner = THIS_MODULE,
190 .id = I2C_DRIVERID_LM90,
191 .flags = I2C_DF_NOTIFY,
192 .attach_adapter = lm90_attach_adapter,
193 .detach_client = lm90_detach_client,
197 * Client data (each client gets its own)
201 struct i2c_client client;
202 struct semaphore update_lock;
203 char valid; /* zero until following fields are valid */
204 unsigned long last_updated; /* in jiffies */
207 /* registers values */
208 s8 temp_input1, temp_low1, temp_high1; /* local */
209 s16 temp_input2, temp_low2, temp_high2; /* remote, combined */
210 s8 temp_crit1, temp_crit2;
212 u8 alarms; /* bitvector */
219 #define show_temp(value, converter) \
220 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
222 struct lm90_data *data = lm90_update_device(dev); \
223 return sprintf(buf, "%d\n", converter(data->value)); \
225 show_temp(temp_input1, TEMP1_FROM_REG);
226 show_temp(temp_input2, TEMP2_FROM_REG);
227 show_temp(temp_low1, TEMP1_FROM_REG);
228 show_temp(temp_low2, TEMP2_FROM_REG);
229 show_temp(temp_high1, TEMP1_FROM_REG);
230 show_temp(temp_high2, TEMP2_FROM_REG);
231 show_temp(temp_crit1, TEMP1_FROM_REG);
232 show_temp(temp_crit2, TEMP1_FROM_REG);
234 #define set_temp1(value, reg) \
235 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
238 struct i2c_client *client = to_i2c_client(dev); \
239 struct lm90_data *data = i2c_get_clientdata(client); \
240 long val = simple_strtol(buf, NULL, 10); \
242 down(&data->update_lock); \
243 if (data->kind == adt7461) \
244 data->value = TEMP1_TO_REG_ADT7461(val); \
246 data->value = TEMP1_TO_REG(val); \
247 i2c_smbus_write_byte_data(client, reg, data->value); \
248 up(&data->update_lock); \
251 #define set_temp2(value, regh, regl) \
252 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
255 struct i2c_client *client = to_i2c_client(dev); \
256 struct lm90_data *data = i2c_get_clientdata(client); \
257 long val = simple_strtol(buf, NULL, 10); \
259 down(&data->update_lock); \
260 if (data->kind == adt7461) \
261 data->value = TEMP2_TO_REG_ADT7461(val); \
263 data->value = TEMP2_TO_REG(val); \
264 i2c_smbus_write_byte_data(client, regh, data->value >> 8); \
265 i2c_smbus_write_byte_data(client, regl, data->value & 0xff); \
266 up(&data->update_lock); \
269 set_temp1(temp_low1, LM90_REG_W_LOCAL_LOW);
270 set_temp2(temp_low2, LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL);
271 set_temp1(temp_high1, LM90_REG_W_LOCAL_HIGH);
272 set_temp2(temp_high2, LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL);
273 set_temp1(temp_crit1, LM90_REG_W_LOCAL_CRIT);
274 set_temp1(temp_crit2, LM90_REG_W_REMOTE_CRIT);
276 #define show_temp_hyst(value, basereg) \
277 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
279 struct lm90_data *data = lm90_update_device(dev); \
280 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->basereg) \
281 - TEMP1_FROM_REG(data->temp_hyst)); \
283 show_temp_hyst(temp_hyst1, temp_crit1);
284 show_temp_hyst(temp_hyst2, temp_crit2);
286 static ssize_t set_temp_hyst1(struct device *dev, struct device_attribute *attr, const char *buf,
289 struct i2c_client *client = to_i2c_client(dev);
290 struct lm90_data *data = i2c_get_clientdata(client);
291 long val = simple_strtol(buf, NULL, 10);
294 down(&data->update_lock);
295 hyst = TEMP1_FROM_REG(data->temp_crit1) - val;
296 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
298 up(&data->update_lock);
302 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
304 struct lm90_data *data = lm90_update_device(dev);
305 return sprintf(buf, "%d\n", data->alarms);
308 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
309 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
310 static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_low1,
312 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
314 static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_high1,
316 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
318 static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit1,
320 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
322 static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst1,
324 static DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_hyst2, NULL);
325 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
331 static int lm90_attach_adapter(struct i2c_adapter *adapter)
333 if (!(adapter->class & I2C_CLASS_HWMON))
335 return i2c_detect(adapter, &addr_data, lm90_detect);
339 * The following function does more than just detection. If detection
340 * succeeds, it also registers the new chip.
342 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
344 struct i2c_client *new_client;
345 struct lm90_data *data;
347 const char *name = "";
349 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
352 if (!(data = kmalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
356 memset(data, 0, sizeof(struct lm90_data));
358 /* The common I2C client data is placed right before the
359 LM90-specific data. */
360 new_client = &data->client;
361 i2c_set_clientdata(new_client, data);
362 new_client->addr = address;
363 new_client->adapter = adapter;
364 new_client->driver = &lm90_driver;
365 new_client->flags = 0;
368 * Now we do the remaining detection. A negative kind means that
369 * the driver was loaded with no force parameter (default), so we
370 * must both detect and identify the chip. A zero kind means that
371 * the driver was loaded with the force parameter, the detection
372 * step shall be skipped. A positive kind means that the driver
373 * was loaded with the force parameter and a given kind of chip is
374 * requested, so both the detection and the identification steps
378 /* Default to an LM90 if forced */
382 if (kind < 0) { /* detection and identification */
383 u8 man_id, chip_id, reg_config1, reg_convrate;
385 man_id = i2c_smbus_read_byte_data(new_client,
387 chip_id = i2c_smbus_read_byte_data(new_client,
389 reg_config1 = i2c_smbus_read_byte_data(new_client,
391 reg_convrate = i2c_smbus_read_byte_data(new_client,
392 LM90_REG_R_CONVRATE);
394 if (man_id == 0x01) { /* National Semiconductor */
397 reg_config2 = i2c_smbus_read_byte_data(new_client,
400 if ((reg_config1 & 0x2A) == 0x00
401 && (reg_config2 & 0xF8) == 0x00
402 && reg_convrate <= 0x09) {
404 && (chip_id & 0xF0) == 0x20) { /* LM90 */
407 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
411 && (chip_id & 0xF0) == 0x10) { /* LM86 */
416 if (man_id == 0x41) { /* Analog Devices */
418 && (chip_id & 0xF0) == 0x40 /* ADM1032 */
419 && (reg_config1 & 0x3F) == 0x00
420 && reg_convrate <= 0x0A) {
424 && chip_id == 0x51 /* ADT7461 */
425 && (reg_config1 & 0x1F) == 0x00 /* check compat mode */
426 && reg_convrate <= 0x0A) {
430 if (man_id == 0x4D) { /* Maxim */
432 * The Maxim variants do NOT have a chip_id register.
433 * Reading from that address will return the last read
434 * value, which in our case is those of the man_id
435 * register. Likewise, the config1 register seems to
436 * lack a low nibble, so the value will be those of the
437 * previous read, so in our case those of the man_id
440 if (chip_id == man_id
441 && (reg_config1 & 0x1F) == (man_id & 0x0F)
442 && reg_convrate <= 0x09) {
447 if (kind <= 0) { /* identification failed */
448 dev_info(&adapter->dev,
449 "Unsupported chip (man_id=0x%02X, "
450 "chip_id=0x%02X).\n", man_id, chip_id);
457 } else if (kind == adm1032) {
459 } else if (kind == lm99) {
461 } else if (kind == lm86) {
463 } else if (kind == max6657) {
465 } else if (kind == adt7461) {
469 /* We can fill in the remaining client fields */
470 strlcpy(new_client->name, name, I2C_NAME_SIZE);
473 init_MUTEX(&data->update_lock);
475 /* Tell the I2C layer a new client has arrived */
476 if ((err = i2c_attach_client(new_client)))
479 /* Initialize the LM90 chip */
480 lm90_init_client(new_client);
482 /* Register sysfs hooks */
483 device_create_file(&new_client->dev, &dev_attr_temp1_input);
484 device_create_file(&new_client->dev, &dev_attr_temp2_input);
485 device_create_file(&new_client->dev, &dev_attr_temp1_min);
486 device_create_file(&new_client->dev, &dev_attr_temp2_min);
487 device_create_file(&new_client->dev, &dev_attr_temp1_max);
488 device_create_file(&new_client->dev, &dev_attr_temp2_max);
489 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
490 device_create_file(&new_client->dev, &dev_attr_temp2_crit);
491 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
492 device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
493 device_create_file(&new_client->dev, &dev_attr_alarms);
503 static void lm90_init_client(struct i2c_client *client)
508 * Start the conversions.
510 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
512 config = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
514 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
515 config & 0xBF); /* run */
518 static int lm90_detach_client(struct i2c_client *client)
522 if ((err = i2c_detach_client(client))) {
523 dev_err(&client->dev, "Client deregistration failed, "
524 "client not detached.\n");
528 kfree(i2c_get_clientdata(client));
532 static struct lm90_data *lm90_update_device(struct device *dev)
534 struct i2c_client *client = to_i2c_client(dev);
535 struct lm90_data *data = i2c_get_clientdata(client);
537 down(&data->update_lock);
539 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
542 dev_dbg(&client->dev, "Updating lm90 data.\n");
543 data->temp_input1 = i2c_smbus_read_byte_data(client,
544 LM90_REG_R_LOCAL_TEMP);
545 data->temp_high1 = i2c_smbus_read_byte_data(client,
546 LM90_REG_R_LOCAL_HIGH);
547 data->temp_low1 = i2c_smbus_read_byte_data(client,
548 LM90_REG_R_LOCAL_LOW);
549 data->temp_crit1 = i2c_smbus_read_byte_data(client,
550 LM90_REG_R_LOCAL_CRIT);
551 data->temp_crit2 = i2c_smbus_read_byte_data(client,
552 LM90_REG_R_REMOTE_CRIT);
553 data->temp_hyst = i2c_smbus_read_byte_data(client,
554 LM90_REG_R_TCRIT_HYST);
557 * There is a trick here. We have to read two registers to
558 * have the remote sensor temperature, but we have to beware
559 * a conversion could occur inbetween the readings. The
560 * datasheet says we should either use the one-shot
561 * conversion register, which we don't want to do (disables
562 * hardware monitoring) or monitor the busy bit, which is
563 * impossible (we can't read the values and monitor that bit
564 * at the exact same time). So the solution used here is to
565 * read the high byte once, then the low byte, then the high
566 * byte again. If the new high byte matches the old one,
567 * then we have a valid reading. Else we have to read the low
568 * byte again, and now we believe we have a correct reading.
570 oldh = i2c_smbus_read_byte_data(client,
571 LM90_REG_R_REMOTE_TEMPH);
572 data->temp_input2 = i2c_smbus_read_byte_data(client,
573 LM90_REG_R_REMOTE_TEMPL);
574 newh = i2c_smbus_read_byte_data(client,
575 LM90_REG_R_REMOTE_TEMPH);
577 data->temp_input2 = i2c_smbus_read_byte_data(client,
578 LM90_REG_R_REMOTE_TEMPL);
580 oldh = i2c_smbus_read_byte_data(client,
581 LM90_REG_R_REMOTE_TEMPH);
582 /* oldh is actually newer */
584 dev_warn(&client->dev, "Remote temperature may be "
588 data->temp_input2 |= (newh << 8);
590 data->temp_high2 = (i2c_smbus_read_byte_data(client,
591 LM90_REG_R_REMOTE_HIGHH) << 8) +
592 i2c_smbus_read_byte_data(client,
593 LM90_REG_R_REMOTE_HIGHL);
594 data->temp_low2 = (i2c_smbus_read_byte_data(client,
595 LM90_REG_R_REMOTE_LOWH) << 8) +
596 i2c_smbus_read_byte_data(client,
597 LM90_REG_R_REMOTE_LOWL);
598 data->alarms = i2c_smbus_read_byte_data(client,
601 data->last_updated = jiffies;
605 up(&data->update_lock);
610 static int __init sensors_lm90_init(void)
612 return i2c_add_driver(&lm90_driver);
615 static void __exit sensors_lm90_exit(void)
617 i2c_del_driver(&lm90_driver);
620 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
621 MODULE_DESCRIPTION("LM90/ADM1032 driver");
622 MODULE_LICENSE("GPL");
624 module_init(sensors_lm90_init);
625 module_exit(sensors_lm90_exit);