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 short normal_i2c_range[] = { I2C_CLIENT_END };
80 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
81 static unsigned int normal_isa_range[] = { I2C_CLIENT_ISA_END };
87 SENSORS_INSMOD_5(lm90, adm1032, lm99, lm86, max6657);
93 #define LM90_REG_R_MAN_ID 0xFE
94 #define LM90_REG_R_CHIP_ID 0xFF
95 #define LM90_REG_R_CONFIG1 0x03
96 #define LM90_REG_W_CONFIG1 0x09
97 #define LM90_REG_R_CONFIG2 0xBF
98 #define LM90_REG_W_CONFIG2 0xBF
99 #define LM90_REG_R_CONVRATE 0x04
100 #define LM90_REG_W_CONVRATE 0x0A
101 #define LM90_REG_R_STATUS 0x02
102 #define LM90_REG_R_LOCAL_TEMP 0x00
103 #define LM90_REG_R_LOCAL_HIGH 0x05
104 #define LM90_REG_W_LOCAL_HIGH 0x0B
105 #define LM90_REG_R_LOCAL_LOW 0x06
106 #define LM90_REG_W_LOCAL_LOW 0x0C
107 #define LM90_REG_R_LOCAL_CRIT 0x20
108 #define LM90_REG_W_LOCAL_CRIT 0x20
109 #define LM90_REG_R_REMOTE_TEMPH 0x01
110 #define LM90_REG_R_REMOTE_TEMPL 0x10
111 #define LM90_REG_R_REMOTE_OFFSH 0x11
112 #define LM90_REG_W_REMOTE_OFFSH 0x11
113 #define LM90_REG_R_REMOTE_OFFSL 0x12
114 #define LM90_REG_W_REMOTE_OFFSL 0x12
115 #define LM90_REG_R_REMOTE_HIGHH 0x07
116 #define LM90_REG_W_REMOTE_HIGHH 0x0D
117 #define LM90_REG_R_REMOTE_HIGHL 0x13
118 #define LM90_REG_W_REMOTE_HIGHL 0x13
119 #define LM90_REG_R_REMOTE_LOWH 0x08
120 #define LM90_REG_W_REMOTE_LOWH 0x0E
121 #define LM90_REG_R_REMOTE_LOWL 0x14
122 #define LM90_REG_W_REMOTE_LOWL 0x14
123 #define LM90_REG_R_REMOTE_CRIT 0x19
124 #define LM90_REG_W_REMOTE_CRIT 0x19
125 #define LM90_REG_R_TCRIT_HYST 0x21
126 #define LM90_REG_W_TCRIT_HYST 0x21
129 * Conversions and various macros
130 * The LM90 uses signed 8-bit values for the local temperatures,
131 * and signed 11-bit values for the remote temperatures (except
132 * T_CRIT). Note that TEMP2_TO_REG does not round values, but
133 * stick to the nearest lower value instead. Fixing it is just
137 #define TEMP1_FROM_REG(val) ((val & 0x80 ? val-0x100 : val) * 1000)
138 #define TEMP1_TO_REG(val) ((val < 0 ? val+0x100*1000 : val) / 1000)
139 #define TEMP2_FROM_REG(val) (((val & 0x8000 ? val-0x10000 : val) >> 5) * 125)
140 #define TEMP2_TO_REG(val) ((((val / 125) << 5) + (val < 0 ? 0x10000 : 0)) & 0xFFE0)
141 #define HYST_FROM_REG(val) (val * 1000)
142 #define HYST_TO_REG(val) (val <= 0 ? 0 : val >= 31000 ? 31 : val / 1000)
145 * Functions declaration
148 static int lm90_attach_adapter(struct i2c_adapter *adapter);
149 static int lm90_detect(struct i2c_adapter *adapter, int address,
151 static void lm90_init_client(struct i2c_client *client);
152 static int lm90_detach_client(struct i2c_client *client);
153 static struct lm90_data *lm90_update_device(struct device *dev);
156 * Driver data (common to all clients)
159 static struct i2c_driver lm90_driver = {
160 .owner = THIS_MODULE,
162 .id = I2C_DRIVERID_LM90,
163 .flags = I2C_DF_NOTIFY,
164 .attach_adapter = lm90_attach_adapter,
165 .detach_client = lm90_detach_client,
169 * Client data (each client gets its own)
173 struct i2c_client client;
174 struct semaphore update_lock;
175 char valid; /* zero until following fields are valid */
176 unsigned long last_updated; /* in jiffies */
178 /* registers values */
179 u8 temp_input1, temp_low1, temp_high1; /* local */
180 u16 temp_input2, temp_low2, temp_high2; /* remote, combined */
181 u8 temp_crit1, temp_crit2;
183 u16 alarms; /* bitvector, combined */
190 static int lm90_id = 0;
196 #define show_temp(value, converter) \
197 static ssize_t show_##value(struct device *dev, char *buf) \
199 struct lm90_data *data = lm90_update_device(dev); \
200 return sprintf(buf, "%d\n", converter(data->value)); \
202 show_temp(temp_input1, TEMP1_FROM_REG);
203 show_temp(temp_input2, TEMP2_FROM_REG);
204 show_temp(temp_low1, TEMP1_FROM_REG);
205 show_temp(temp_low2, TEMP2_FROM_REG);
206 show_temp(temp_high1, TEMP1_FROM_REG);
207 show_temp(temp_high2, TEMP2_FROM_REG);
208 show_temp(temp_crit1, TEMP1_FROM_REG);
209 show_temp(temp_crit2, TEMP1_FROM_REG);
211 #define set_temp1(value, reg) \
212 static ssize_t set_##value(struct device *dev, const char *buf, \
215 struct i2c_client *client = to_i2c_client(dev); \
216 struct lm90_data *data = i2c_get_clientdata(client); \
217 data->value = TEMP1_TO_REG(simple_strtol(buf, NULL, 10)); \
218 i2c_smbus_write_byte_data(client, reg, data->value); \
221 #define set_temp2(value, regh, regl) \
222 static ssize_t set_##value(struct device *dev, const char *buf, \
225 struct i2c_client *client = to_i2c_client(dev); \
226 struct lm90_data *data = i2c_get_clientdata(client); \
227 data->value = TEMP2_TO_REG(simple_strtol(buf, NULL, 10)); \
228 i2c_smbus_write_byte_data(client, regh, data->value >> 8); \
229 i2c_smbus_write_byte_data(client, regl, data->value & 0xff); \
232 set_temp1(temp_low1, LM90_REG_W_LOCAL_LOW);
233 set_temp2(temp_low2, LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL);
234 set_temp1(temp_high1, LM90_REG_W_LOCAL_HIGH);
235 set_temp2(temp_high2, LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL);
236 set_temp1(temp_crit1, LM90_REG_W_LOCAL_CRIT);
237 set_temp1(temp_crit2, LM90_REG_W_REMOTE_CRIT);
239 #define show_temp_hyst(value, basereg) \
240 static ssize_t show_##value(struct device *dev, char *buf) \
242 struct lm90_data *data = lm90_update_device(dev); \
243 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->basereg) \
244 - HYST_FROM_REG(data->temp_hyst)); \
246 show_temp_hyst(temp_hyst1, temp_crit1);
247 show_temp_hyst(temp_hyst2, temp_crit2);
249 static ssize_t set_temp_hyst1(struct device *dev, const char *buf,
252 struct i2c_client *client = to_i2c_client(dev);
253 struct lm90_data *data = i2c_get_clientdata(client);
254 int hyst = TEMP1_FROM_REG(data->temp_crit1) -
255 simple_strtol(buf, NULL, 10);
256 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
261 static ssize_t show_alarms(struct device *dev, char *buf)
263 struct lm90_data *data = lm90_update_device(dev);
264 return sprintf(buf, "%d\n", data->alarms);
267 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
268 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
269 static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_low1,
271 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
273 static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_high1,
275 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
277 static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit1,
279 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
281 static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst1,
283 static DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temp_hyst2, NULL);
284 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
290 static int lm90_attach_adapter(struct i2c_adapter *adapter)
292 if (!(adapter->class & I2C_CLASS_HWMON))
294 return i2c_detect(adapter, &addr_data, lm90_detect);
298 * The following function does more than just detection. If detection
299 * succeeds, it also registers the new chip.
301 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
303 struct i2c_client *new_client;
304 struct lm90_data *data;
306 const char *name = "";
308 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
311 if (!(data = kmalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
315 memset(data, 0, sizeof(struct lm90_data));
317 /* The common I2C client data is placed right before the
318 LM90-specific data. */
319 new_client = &data->client;
320 i2c_set_clientdata(new_client, data);
321 new_client->addr = address;
322 new_client->adapter = adapter;
323 new_client->driver = &lm90_driver;
324 new_client->flags = 0;
327 * Now we do the remaining detection. A negative kind means that
328 * the driver was loaded with no force parameter (default), so we
329 * must both detect and identify the chip. A zero kind means that
330 * the driver was loaded with the force parameter, the detection
331 * step shall be skipped. A positive kind means that the driver
332 * was loaded with the force parameter and a given kind of chip is
333 * requested, so both the detection and the identification steps
337 /* Default to an LM90 if forced */
341 if (kind < 0) { /* detection and identification */
342 u8 man_id, chip_id, reg_config1, reg_convrate;
344 man_id = i2c_smbus_read_byte_data(new_client,
346 chip_id = i2c_smbus_read_byte_data(new_client,
348 reg_config1 = i2c_smbus_read_byte_data(new_client,
350 reg_convrate = i2c_smbus_read_byte_data(new_client,
351 LM90_REG_R_CONVRATE);
353 if (man_id == 0x01) { /* National Semiconductor */
356 reg_config2 = i2c_smbus_read_byte_data(new_client,
359 if ((reg_config1 & 0x2A) == 0x00
360 && (reg_config2 & 0xF8) == 0x00
361 && reg_convrate <= 0x09) {
363 && (chip_id & 0xF0) == 0x20) { /* LM90 */
366 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
370 && (chip_id & 0xF0) == 0x10) { /* LM86 */
375 if (man_id == 0x41) { /* Analog Devices */
377 && (chip_id & 0xF0) == 0x40 /* ADM1032 */
378 && (reg_config1 & 0x3F) == 0x00
379 && reg_convrate <= 0x0A) {
383 if (man_id == 0x4D) { /* Maxim */
385 && (reg_config1 & 0x1F) == 0
386 && reg_convrate <= 0x09) {
391 if (kind <= 0) { /* identification failed */
392 dev_info(&adapter->dev,
393 "Unsupported chip (man_id=0x%02X, "
394 "chip_id=0x%02X).\n", man_id, chip_id);
401 } else if (kind == adm1032) {
403 } else if (kind == lm99) {
405 } else if (kind == lm86) {
407 } else if (kind == max6657) {
411 /* We can fill in the remaining client fields */
412 strlcpy(new_client->name, name, I2C_NAME_SIZE);
413 new_client->id = lm90_id++;
415 init_MUTEX(&data->update_lock);
417 /* Tell the I2C layer a new client has arrived */
418 if ((err = i2c_attach_client(new_client)))
421 /* Initialize the LM90 chip */
422 lm90_init_client(new_client);
424 /* Register sysfs hooks */
425 device_create_file(&new_client->dev, &dev_attr_temp1_input);
426 device_create_file(&new_client->dev, &dev_attr_temp2_input);
427 device_create_file(&new_client->dev, &dev_attr_temp1_min);
428 device_create_file(&new_client->dev, &dev_attr_temp2_min);
429 device_create_file(&new_client->dev, &dev_attr_temp1_max);
430 device_create_file(&new_client->dev, &dev_attr_temp2_max);
431 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
432 device_create_file(&new_client->dev, &dev_attr_temp2_crit);
433 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
434 device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
435 device_create_file(&new_client->dev, &dev_attr_alarms);
445 static void lm90_init_client(struct i2c_client *client)
450 * Start the conversions.
452 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
454 config = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
456 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
457 config & 0xBF); /* run */
460 static int lm90_detach_client(struct i2c_client *client)
464 if ((err = i2c_detach_client(client))) {
465 dev_err(&client->dev, "Client deregistration failed, "
466 "client not detached.\n");
470 kfree(i2c_get_clientdata(client));
474 static struct lm90_data *lm90_update_device(struct device *dev)
476 struct i2c_client *client = to_i2c_client(dev);
477 struct lm90_data *data = i2c_get_clientdata(client);
479 down(&data->update_lock);
481 if ((jiffies - data->last_updated > HZ * 2) ||
482 (jiffies < data->last_updated) ||
486 dev_dbg(&client->dev, "Updating lm90 data.\n");
487 data->temp_input1 = i2c_smbus_read_byte_data(client,
488 LM90_REG_R_LOCAL_TEMP);
489 data->temp_high1 = i2c_smbus_read_byte_data(client,
490 LM90_REG_R_LOCAL_HIGH);
491 data->temp_low1 = i2c_smbus_read_byte_data(client,
492 LM90_REG_R_LOCAL_LOW);
493 data->temp_crit1 = i2c_smbus_read_byte_data(client,
494 LM90_REG_R_LOCAL_CRIT);
495 data->temp_crit2 = i2c_smbus_read_byte_data(client,
496 LM90_REG_R_REMOTE_CRIT);
497 data->temp_hyst = i2c_smbus_read_byte_data(client,
498 LM90_REG_R_TCRIT_HYST);
501 * There is a trick here. We have to read two registers to
502 * have the remote sensor temperature, but we have to beware
503 * a conversion could occur inbetween the readings. The
504 * datasheet says we should either use the one-shot
505 * conversion register, which we don't want to do (disables
506 * hardware monitoring) or monitor the busy bit, which is
507 * impossible (we can't read the values and monitor that bit
508 * at the exact same time). So the solution used here is to
509 * read the high byte once, then the low byte, then the high
510 * byte again. If the new high byte matches the old one,
511 * then we have a valid reading. Else we have to read the low
512 * byte again, and now we believe we have a correct reading.
514 oldh = i2c_smbus_read_byte_data(client,
515 LM90_REG_R_REMOTE_TEMPH);
516 data->temp_input2 = i2c_smbus_read_byte_data(client,
517 LM90_REG_R_REMOTE_TEMPL);
518 newh = i2c_smbus_read_byte_data(client,
519 LM90_REG_R_REMOTE_TEMPH);
521 data->temp_input2 = i2c_smbus_read_byte_data(client,
522 LM90_REG_R_REMOTE_TEMPL);
524 oldh = i2c_smbus_read_byte_data(client,
525 LM90_REG_R_REMOTE_TEMPH);
526 /* oldh is actually newer */
528 dev_warn(&client->dev, "Remote temperature may be "
532 data->temp_input2 |= (newh << 8);
534 data->temp_high2 = (i2c_smbus_read_byte_data(client,
535 LM90_REG_R_REMOTE_HIGHH) << 8) +
536 i2c_smbus_read_byte_data(client,
537 LM90_REG_R_REMOTE_HIGHL);
538 data->temp_low2 = (i2c_smbus_read_byte_data(client,
539 LM90_REG_R_REMOTE_LOWH) << 8) +
540 i2c_smbus_read_byte_data(client,
541 LM90_REG_R_REMOTE_LOWL);
542 data->alarms = i2c_smbus_read_byte_data(client,
545 data->last_updated = jiffies;
549 up(&data->update_lock);
554 static int __init sensors_lm90_init(void)
556 return i2c_add_driver(&lm90_driver);
559 static void __exit sensors_lm90_exit(void)
561 i2c_del_driver(&lm90_driver);
564 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
565 MODULE_DESCRIPTION("LM90/ADM1032 driver");
566 MODULE_LICENSE("GPL");
568 module_init(sensors_lm90_init);
569 module_exit(sensors_lm90_exit);