2 * lm90.c - Part of lm_sensors, Linux kernel modules for hardware
4 * Copyright (C) 2003-2005 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/hwmon-sysfs.h>
79 #include <linux/hwmon.h>
80 #include <linux/err.h>
84 * Address is fully defined internally and cannot be changed except for
86 * LM86, LM89, LM90, LM99, ADM1032, MAX6657 and MAX6658 have address 0x4c.
87 * LM89-1, and LM99-1 have address 0x4d.
88 * MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported).
89 * ADT7461 always has address 0x4c.
92 static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END };
98 I2C_CLIENT_INSMOD_6(lm90, adm1032, lm99, lm86, max6657, adt7461);
104 #define LM90_REG_R_MAN_ID 0xFE
105 #define LM90_REG_R_CHIP_ID 0xFF
106 #define LM90_REG_R_CONFIG1 0x03
107 #define LM90_REG_W_CONFIG1 0x09
108 #define LM90_REG_R_CONFIG2 0xBF
109 #define LM90_REG_W_CONFIG2 0xBF
110 #define LM90_REG_R_CONVRATE 0x04
111 #define LM90_REG_W_CONVRATE 0x0A
112 #define LM90_REG_R_STATUS 0x02
113 #define LM90_REG_R_LOCAL_TEMP 0x00
114 #define LM90_REG_R_LOCAL_HIGH 0x05
115 #define LM90_REG_W_LOCAL_HIGH 0x0B
116 #define LM90_REG_R_LOCAL_LOW 0x06
117 #define LM90_REG_W_LOCAL_LOW 0x0C
118 #define LM90_REG_R_LOCAL_CRIT 0x20
119 #define LM90_REG_W_LOCAL_CRIT 0x20
120 #define LM90_REG_R_REMOTE_TEMPH 0x01
121 #define LM90_REG_R_REMOTE_TEMPL 0x10
122 #define LM90_REG_R_REMOTE_OFFSH 0x11
123 #define LM90_REG_W_REMOTE_OFFSH 0x11
124 #define LM90_REG_R_REMOTE_OFFSL 0x12
125 #define LM90_REG_W_REMOTE_OFFSL 0x12
126 #define LM90_REG_R_REMOTE_HIGHH 0x07
127 #define LM90_REG_W_REMOTE_HIGHH 0x0D
128 #define LM90_REG_R_REMOTE_HIGHL 0x13
129 #define LM90_REG_W_REMOTE_HIGHL 0x13
130 #define LM90_REG_R_REMOTE_LOWH 0x08
131 #define LM90_REG_W_REMOTE_LOWH 0x0E
132 #define LM90_REG_R_REMOTE_LOWL 0x14
133 #define LM90_REG_W_REMOTE_LOWL 0x14
134 #define LM90_REG_R_REMOTE_CRIT 0x19
135 #define LM90_REG_W_REMOTE_CRIT 0x19
136 #define LM90_REG_R_TCRIT_HYST 0x21
137 #define LM90_REG_W_TCRIT_HYST 0x21
140 * Conversions and various macros
141 * For local temperatures and limits, critical limits and the hysteresis
142 * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius.
143 * For remote temperatures and limits, it uses signed 11-bit values with
144 * LSB = 0.125 degree Celsius, left-justified in 16-bit registers.
147 #define TEMP1_FROM_REG(val) ((val) * 1000)
148 #define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \
149 (val) >= 127000 ? 127 : \
150 (val) < 0 ? ((val) - 500) / 1000 : \
151 ((val) + 500) / 1000)
152 #define TEMP2_FROM_REG(val) ((val) / 32 * 125)
153 #define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \
154 (val) >= 127875 ? 0x7FE0 : \
155 (val) < 0 ? ((val) - 62) / 125 * 32 : \
156 ((val) + 62) / 125 * 32)
157 #define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
158 ((val) + 500) / 1000)
161 * ADT7461 is almost identical to LM90 except that attempts to write
162 * values that are outside the range 0 < temp < 127 are treated as
163 * the boundary value.
166 #define TEMP1_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
167 (val) >= 127000 ? 127 : \
168 ((val) + 500) / 1000)
169 #define TEMP2_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
170 (val) >= 127750 ? 0x7FC0 : \
171 ((val) + 125) / 250 * 64)
174 * Functions declaration
177 static int lm90_attach_adapter(struct i2c_adapter *adapter);
178 static int lm90_detect(struct i2c_adapter *adapter, int address,
180 static void lm90_init_client(struct i2c_client *client);
181 static int lm90_detach_client(struct i2c_client *client);
182 static struct lm90_data *lm90_update_device(struct device *dev);
185 * Driver data (common to all clients)
188 static struct i2c_driver lm90_driver = {
189 .owner = THIS_MODULE,
191 .id = I2C_DRIVERID_LM90,
192 .flags = I2C_DF_NOTIFY,
193 .attach_adapter = lm90_attach_adapter,
194 .detach_client = lm90_detach_client,
198 * Client data (each client gets its own)
202 struct i2c_client client;
203 struct class_device *class_dev;
204 struct semaphore update_lock;
205 char valid; /* zero until following fields are valid */
206 unsigned long last_updated; /* in jiffies */
209 /* registers values */
210 s8 temp8[5]; /* 0: local input
213 3: local critical limit
214 4: remote critical limit */
215 s16 temp11[3]; /* 0: remote input
217 2: remote high limit */
219 u8 alarms; /* bitvector */
226 static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
229 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
230 struct lm90_data *data = lm90_update_device(dev);
231 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index]));
234 static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
235 const char *buf, size_t count)
237 static const u8 reg[4] = {
238 LM90_REG_W_LOCAL_LOW,
239 LM90_REG_W_LOCAL_HIGH,
240 LM90_REG_W_LOCAL_CRIT,
241 LM90_REG_W_REMOTE_CRIT,
244 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
245 struct i2c_client *client = to_i2c_client(dev);
246 struct lm90_data *data = i2c_get_clientdata(client);
247 long val = simple_strtol(buf, NULL, 10);
248 int nr = attr->index;
250 down(&data->update_lock);
251 if (data->kind == adt7461)
252 data->temp8[nr] = TEMP1_TO_REG_ADT7461(val);
254 data->temp8[nr] = TEMP1_TO_REG(val);
255 i2c_smbus_write_byte_data(client, reg[nr - 1], data->temp8[nr]);
256 up(&data->update_lock);
260 static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
263 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
264 struct lm90_data *data = lm90_update_device(dev);
265 return sprintf(buf, "%d\n", TEMP2_FROM_REG(data->temp11[attr->index]));
268 static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
269 const char *buf, size_t count)
271 static const u8 reg[4] = {
272 LM90_REG_W_REMOTE_LOWH,
273 LM90_REG_W_REMOTE_LOWL,
274 LM90_REG_W_REMOTE_HIGHH,
275 LM90_REG_W_REMOTE_HIGHL,
278 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
279 struct i2c_client *client = to_i2c_client(dev);
280 struct lm90_data *data = i2c_get_clientdata(client);
281 long val = simple_strtol(buf, NULL, 10);
282 int nr = attr->index;
284 down(&data->update_lock);
285 if (data->kind == adt7461)
286 data->temp11[nr] = TEMP2_TO_REG_ADT7461(val);
288 data->temp11[nr] = TEMP2_TO_REG(val);
289 i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2],
290 data->temp11[nr] >> 8);
291 i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2 + 1],
292 data->temp11[nr] & 0xff);
293 up(&data->update_lock);
297 static ssize_t show_temphyst(struct device *dev, struct device_attribute *devattr,
300 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
301 struct lm90_data *data = lm90_update_device(dev);
302 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index])
303 - TEMP1_FROM_REG(data->temp_hyst));
306 static ssize_t set_temphyst(struct device *dev, struct device_attribute *dummy,
307 const char *buf, size_t count)
309 struct i2c_client *client = to_i2c_client(dev);
310 struct lm90_data *data = i2c_get_clientdata(client);
311 long val = simple_strtol(buf, NULL, 10);
314 down(&data->update_lock);
315 hyst = TEMP1_FROM_REG(data->temp8[3]) - val;
316 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
318 up(&data->update_lock);
322 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
325 struct lm90_data *data = lm90_update_device(dev);
326 return sprintf(buf, "%d\n", data->alarms);
329 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp8, NULL, 0);
330 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp11, NULL, 0);
331 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp8,
333 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp11,
335 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp8,
337 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp11,
339 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp8,
341 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp8,
343 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temphyst,
345 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temphyst, NULL, 4);
346 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
352 static int lm90_read_reg(struct i2c_client* client, u8 reg, u8 *value)
356 err = i2c_smbus_read_byte_data(client, reg);
359 dev_warn(&client->dev, "Register %#02x read failed (%d)\n",
368 static int lm90_attach_adapter(struct i2c_adapter *adapter)
370 if (!(adapter->class & I2C_CLASS_HWMON))
372 return i2c_probe(adapter, &addr_data, lm90_detect);
376 * The following function does more than just detection. If detection
377 * succeeds, it also registers the new chip.
379 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
381 struct i2c_client *new_client;
382 struct lm90_data *data;
384 const char *name = "";
386 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
389 if (!(data = kzalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
394 /* The common I2C client data is placed right before the
395 LM90-specific data. */
396 new_client = &data->client;
397 i2c_set_clientdata(new_client, data);
398 new_client->addr = address;
399 new_client->adapter = adapter;
400 new_client->driver = &lm90_driver;
401 new_client->flags = 0;
404 * Now we do the remaining detection. A negative kind means that
405 * the driver was loaded with no force parameter (default), so we
406 * must both detect and identify the chip. A zero kind means that
407 * the driver was loaded with the force parameter, the detection
408 * step shall be skipped. A positive kind means that the driver
409 * was loaded with the force parameter and a given kind of chip is
410 * requested, so both the detection and the identification steps
414 /* Default to an LM90 if forced */
418 if (kind < 0) { /* detection and identification */
419 u8 man_id, chip_id, reg_config1, reg_convrate;
421 if (lm90_read_reg(new_client, LM90_REG_R_MAN_ID,
423 || lm90_read_reg(new_client, LM90_REG_R_CHIP_ID,
425 || lm90_read_reg(new_client, LM90_REG_R_CONFIG1,
427 || lm90_read_reg(new_client, LM90_REG_R_CONVRATE,
431 if (man_id == 0x01) { /* National Semiconductor */
434 if (lm90_read_reg(new_client, LM90_REG_R_CONFIG2,
438 if ((reg_config1 & 0x2A) == 0x00
439 && (reg_config2 & 0xF8) == 0x00
440 && reg_convrate <= 0x09) {
442 && (chip_id & 0xF0) == 0x20) { /* LM90 */
445 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
449 && (chip_id & 0xF0) == 0x10) { /* LM86 */
454 if (man_id == 0x41) { /* Analog Devices */
456 && (chip_id & 0xF0) == 0x40 /* ADM1032 */
457 && (reg_config1 & 0x3F) == 0x00
458 && reg_convrate <= 0x0A) {
462 && chip_id == 0x51 /* ADT7461 */
463 && (reg_config1 & 0x1F) == 0x00 /* check compat mode */
464 && reg_convrate <= 0x0A) {
468 if (man_id == 0x4D) { /* Maxim */
470 * The Maxim variants do NOT have a chip_id register.
471 * Reading from that address will return the last read
472 * value, which in our case is those of the man_id
473 * register. Likewise, the config1 register seems to
474 * lack a low nibble, so the value will be those of the
475 * previous read, so in our case those of the man_id
478 if (chip_id == man_id
479 && (reg_config1 & 0x1F) == (man_id & 0x0F)
480 && reg_convrate <= 0x09) {
485 if (kind <= 0) { /* identification failed */
486 dev_info(&adapter->dev,
487 "Unsupported chip (man_id=0x%02X, "
488 "chip_id=0x%02X).\n", man_id, chip_id);
495 } else if (kind == adm1032) {
497 } else if (kind == lm99) {
499 } else if (kind == lm86) {
501 } else if (kind == max6657) {
503 } else if (kind == adt7461) {
507 /* We can fill in the remaining client fields */
508 strlcpy(new_client->name, name, I2C_NAME_SIZE);
511 init_MUTEX(&data->update_lock);
513 /* Tell the I2C layer a new client has arrived */
514 if ((err = i2c_attach_client(new_client)))
517 /* Initialize the LM90 chip */
518 lm90_init_client(new_client);
520 /* Register sysfs hooks */
521 data->class_dev = hwmon_device_register(&new_client->dev);
522 if (IS_ERR(data->class_dev)) {
523 err = PTR_ERR(data->class_dev);
527 device_create_file(&new_client->dev,
528 &sensor_dev_attr_temp1_input.dev_attr);
529 device_create_file(&new_client->dev,
530 &sensor_dev_attr_temp2_input.dev_attr);
531 device_create_file(&new_client->dev,
532 &sensor_dev_attr_temp1_min.dev_attr);
533 device_create_file(&new_client->dev,
534 &sensor_dev_attr_temp2_min.dev_attr);
535 device_create_file(&new_client->dev,
536 &sensor_dev_attr_temp1_max.dev_attr);
537 device_create_file(&new_client->dev,
538 &sensor_dev_attr_temp2_max.dev_attr);
539 device_create_file(&new_client->dev,
540 &sensor_dev_attr_temp1_crit.dev_attr);
541 device_create_file(&new_client->dev,
542 &sensor_dev_attr_temp2_crit.dev_attr);
543 device_create_file(&new_client->dev,
544 &sensor_dev_attr_temp1_crit_hyst.dev_attr);
545 device_create_file(&new_client->dev,
546 &sensor_dev_attr_temp2_crit_hyst.dev_attr);
547 device_create_file(&new_client->dev, &dev_attr_alarms);
552 i2c_detach_client(new_client);
559 static void lm90_init_client(struct i2c_client *client)
564 * Start the conversions.
566 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
568 if (lm90_read_reg(client, LM90_REG_R_CONFIG1, &config) < 0) {
569 dev_warn(&client->dev, "Initialization failed!\n");
573 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
574 config & 0xBF); /* run */
577 static int lm90_detach_client(struct i2c_client *client)
579 struct lm90_data *data = i2c_get_clientdata(client);
582 hwmon_device_unregister(data->class_dev);
584 if ((err = i2c_detach_client(client)))
591 static struct lm90_data *lm90_update_device(struct device *dev)
593 struct i2c_client *client = to_i2c_client(dev);
594 struct lm90_data *data = i2c_get_clientdata(client);
596 down(&data->update_lock);
598 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
601 dev_dbg(&client->dev, "Updating lm90 data.\n");
602 lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP, &data->temp8[0]);
603 lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[1]);
604 lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH, &data->temp8[2]);
605 lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT, &data->temp8[3]);
606 lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT, &data->temp8[4]);
607 lm90_read_reg(client, LM90_REG_R_TCRIT_HYST, &data->temp_hyst);
610 * There is a trick here. We have to read two registers to
611 * have the remote sensor temperature, but we have to beware
612 * a conversion could occur inbetween the readings. The
613 * datasheet says we should either use the one-shot
614 * conversion register, which we don't want to do (disables
615 * hardware monitoring) or monitor the busy bit, which is
616 * impossible (we can't read the values and monitor that bit
617 * at the exact same time). So the solution used here is to
618 * read the high byte once, then the low byte, then the high
619 * byte again. If the new high byte matches the old one,
620 * then we have a valid reading. Else we have to read the low
621 * byte again, and now we believe we have a correct reading.
623 if (lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &oldh) == 0
624 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0
625 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &newh) == 0
627 || lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0))
628 data->temp11[0] = (newh << 8) | l;
630 if (lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &newh) == 0
631 && lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL, &l) == 0)
632 data->temp11[1] = (newh << 8) | l;
633 if (lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &newh) == 0
634 && lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL, &l) == 0)
635 data->temp11[2] = (newh << 8) | l;
636 lm90_read_reg(client, LM90_REG_R_STATUS, &data->alarms);
638 data->last_updated = jiffies;
642 up(&data->update_lock);
647 static int __init sensors_lm90_init(void)
649 return i2c_add_driver(&lm90_driver);
652 static void __exit sensors_lm90_exit(void)
654 i2c_del_driver(&lm90_driver);
657 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
658 MODULE_DESCRIPTION("LM90/ADM1032 driver");
659 MODULE_LICENSE("GPL");
661 module_init(sensors_lm90_init);
662 module_exit(sensors_lm90_exit);