xref: /openbmc/linux/drivers/hwmon/lm90.c (revision f42b3800)
1 /*
2  * lm90.c - Part of lm_sensors, Linux kernel modules for hardware
3  *          monitoring
4  * Copyright (C) 2003-2006  Jean Delvare <khali@linux-fr.org>
5  *
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
12  *
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.
23  *
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
29  *
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://www.analog.com/en/prod/0,2877,ADM1032,00.html
35  * Among others, it has a higher accuracy than the LM90, much like the
36  * LM86 does.
37  *
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. These chips lack the remote temperature
45  * offset feature.
46  *
47  * This driver also supports the MAX6680 and MAX6681, two other sensor
48  * chips made by Maxim. These are quite similar to the other Maxim
49  * chips. Complete datasheet can be obtained at:
50  *   http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
51  * The MAX6680 and MAX6681 only differ in the pinout so they can be
52  * treated identically.
53  *
54  * This driver also supports the ADT7461 chip from Analog Devices but
55  * only in its "compatability mode". If an ADT7461 chip is found but
56  * is configured in non-compatible mode (where its temperature
57  * register values are decoded differently) it is ignored by this
58  * driver. Complete datasheet can be obtained from Analog's website
59  * at:
60  *   http://www.analog.com/en/prod/0,2877,ADT7461,00.html
61  *
62  * Since the LM90 was the first chipset supported by this driver, most
63  * comments will refer to this chipset, but are actually general and
64  * concern all supported chipsets, unless mentioned otherwise.
65  *
66  * This program is free software; you can redistribute it and/or modify
67  * it under the terms of the GNU General Public License as published by
68  * the Free Software Foundation; either version 2 of the License, or
69  * (at your option) any later version.
70  *
71  * This program is distributed in the hope that it will be useful,
72  * but WITHOUT ANY WARRANTY; without even the implied warranty of
73  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
74  * GNU General Public License for more details.
75  *
76  * You should have received a copy of the GNU General Public License
77  * along with this program; if not, write to the Free Software
78  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
79  */
80 
81 #include <linux/module.h>
82 #include <linux/init.h>
83 #include <linux/slab.h>
84 #include <linux/jiffies.h>
85 #include <linux/i2c.h>
86 #include <linux/hwmon-sysfs.h>
87 #include <linux/hwmon.h>
88 #include <linux/err.h>
89 #include <linux/mutex.h>
90 #include <linux/sysfs.h>
91 
92 /*
93  * Addresses to scan
94  * Address is fully defined internally and cannot be changed except for
95  * MAX6659, MAX6680 and MAX6681.
96  * LM86, LM89, LM90, LM99, ADM1032, ADM1032-1, ADT7461, MAX6657 and MAX6658
97  * have address 0x4c.
98  * ADM1032-2, ADT7461-2, LM89-1, and LM99-1 have address 0x4d.
99  * MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported).
100  * MAX6680 and MAX6681 can have address 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
101  * 0x4c, 0x4d or 0x4e.
102  */
103 
104 static const unsigned short normal_i2c[] = {
105 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
106 
107 /*
108  * Insmod parameters
109  */
110 
111 I2C_CLIENT_INSMOD_7(lm90, adm1032, lm99, lm86, max6657, adt7461, max6680);
112 
113 /*
114  * The LM90 registers
115  */
116 
117 #define LM90_REG_R_MAN_ID		0xFE
118 #define LM90_REG_R_CHIP_ID		0xFF
119 #define LM90_REG_R_CONFIG1		0x03
120 #define LM90_REG_W_CONFIG1		0x09
121 #define LM90_REG_R_CONFIG2		0xBF
122 #define LM90_REG_W_CONFIG2		0xBF
123 #define LM90_REG_R_CONVRATE		0x04
124 #define LM90_REG_W_CONVRATE		0x0A
125 #define LM90_REG_R_STATUS		0x02
126 #define LM90_REG_R_LOCAL_TEMP		0x00
127 #define LM90_REG_R_LOCAL_HIGH		0x05
128 #define LM90_REG_W_LOCAL_HIGH		0x0B
129 #define LM90_REG_R_LOCAL_LOW		0x06
130 #define LM90_REG_W_LOCAL_LOW		0x0C
131 #define LM90_REG_R_LOCAL_CRIT		0x20
132 #define LM90_REG_W_LOCAL_CRIT		0x20
133 #define LM90_REG_R_REMOTE_TEMPH		0x01
134 #define LM90_REG_R_REMOTE_TEMPL		0x10
135 #define LM90_REG_R_REMOTE_OFFSH		0x11
136 #define LM90_REG_W_REMOTE_OFFSH		0x11
137 #define LM90_REG_R_REMOTE_OFFSL		0x12
138 #define LM90_REG_W_REMOTE_OFFSL		0x12
139 #define LM90_REG_R_REMOTE_HIGHH		0x07
140 #define LM90_REG_W_REMOTE_HIGHH		0x0D
141 #define LM90_REG_R_REMOTE_HIGHL		0x13
142 #define LM90_REG_W_REMOTE_HIGHL		0x13
143 #define LM90_REG_R_REMOTE_LOWH		0x08
144 #define LM90_REG_W_REMOTE_LOWH		0x0E
145 #define LM90_REG_R_REMOTE_LOWL		0x14
146 #define LM90_REG_W_REMOTE_LOWL		0x14
147 #define LM90_REG_R_REMOTE_CRIT		0x19
148 #define LM90_REG_W_REMOTE_CRIT		0x19
149 #define LM90_REG_R_TCRIT_HYST		0x21
150 #define LM90_REG_W_TCRIT_HYST		0x21
151 
152 /*
153  * Conversions and various macros
154  * For local temperatures and limits, critical limits and the hysteresis
155  * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius.
156  * For remote temperatures and limits, it uses signed 11-bit values with
157  * LSB = 0.125 degree Celsius, left-justified in 16-bit registers.
158  */
159 
160 #define TEMP1_FROM_REG(val)	((val) * 1000)
161 #define TEMP1_TO_REG(val)	((val) <= -128000 ? -128 : \
162 				 (val) >= 127000 ? 127 : \
163 				 (val) < 0 ? ((val) - 500) / 1000 : \
164 				 ((val) + 500) / 1000)
165 #define TEMP2_FROM_REG(val)	((val) / 32 * 125)
166 #define TEMP2_TO_REG(val)	((val) <= -128000 ? 0x8000 : \
167 				 (val) >= 127875 ? 0x7FE0 : \
168 				 (val) < 0 ? ((val) - 62) / 125 * 32 : \
169 				 ((val) + 62) / 125 * 32)
170 #define HYST_TO_REG(val)	((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \
171 				 ((val) + 500) / 1000)
172 
173 /*
174  * ADT7461 is almost identical to LM90 except that attempts to write
175  * values that are outside the range 0 < temp < 127 are treated as
176  * the boundary value.
177  */
178 
179 #define TEMP1_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
180 				 (val) >= 127000 ? 127 : \
181 				 ((val) + 500) / 1000)
182 #define TEMP2_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \
183 				 (val) >= 127750 ? 0x7FC0 : \
184 				 ((val) + 125) / 250 * 64)
185 
186 /*
187  * Functions declaration
188  */
189 
190 static int lm90_attach_adapter(struct i2c_adapter *adapter);
191 static int lm90_detect(struct i2c_adapter *adapter, int address,
192 	int kind);
193 static void lm90_init_client(struct i2c_client *client);
194 static int lm90_detach_client(struct i2c_client *client);
195 static struct lm90_data *lm90_update_device(struct device *dev);
196 
197 /*
198  * Driver data (common to all clients)
199  */
200 
201 static struct i2c_driver lm90_driver = {
202 	.driver = {
203 		.name	= "lm90",
204 	},
205 	.attach_adapter	= lm90_attach_adapter,
206 	.detach_client	= lm90_detach_client,
207 };
208 
209 /*
210  * Client data (each client gets its own)
211  */
212 
213 struct lm90_data {
214 	struct i2c_client client;
215 	struct device *hwmon_dev;
216 	struct mutex update_lock;
217 	char valid; /* zero until following fields are valid */
218 	unsigned long last_updated; /* in jiffies */
219 	int kind;
220 
221 	/* registers values */
222 	s8 temp8[5];	/* 0: local input
223 			   1: local low limit
224 			   2: local high limit
225 			   3: local critical limit
226 			   4: remote critical limit */
227 	s16 temp11[4];	/* 0: remote input
228 			   1: remote low limit
229 			   2: remote high limit
230 			   3: remote offset (except max6657) */
231 	u8 temp_hyst;
232 	u8 alarms; /* bitvector */
233 };
234 
235 /*
236  * Sysfs stuff
237  */
238 
239 static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
240 			  char *buf)
241 {
242 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
243 	struct lm90_data *data = lm90_update_device(dev);
244 	return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index]));
245 }
246 
247 static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
248 			 const char *buf, size_t count)
249 {
250 	static const u8 reg[4] = {
251 		LM90_REG_W_LOCAL_LOW,
252 		LM90_REG_W_LOCAL_HIGH,
253 		LM90_REG_W_LOCAL_CRIT,
254 		LM90_REG_W_REMOTE_CRIT,
255 	};
256 
257 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
258 	struct i2c_client *client = to_i2c_client(dev);
259 	struct lm90_data *data = i2c_get_clientdata(client);
260 	long val = simple_strtol(buf, NULL, 10);
261 	int nr = attr->index;
262 
263 	mutex_lock(&data->update_lock);
264 	if (data->kind == adt7461)
265 		data->temp8[nr] = TEMP1_TO_REG_ADT7461(val);
266 	else
267 		data->temp8[nr] = TEMP1_TO_REG(val);
268 	i2c_smbus_write_byte_data(client, reg[nr - 1], data->temp8[nr]);
269 	mutex_unlock(&data->update_lock);
270 	return count;
271 }
272 
273 static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
274 			   char *buf)
275 {
276 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
277 	struct lm90_data *data = lm90_update_device(dev);
278 	return sprintf(buf, "%d\n", TEMP2_FROM_REG(data->temp11[attr->index]));
279 }
280 
281 static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
282 			  const char *buf, size_t count)
283 {
284 	static const u8 reg[6] = {
285 		LM90_REG_W_REMOTE_LOWH,
286 		LM90_REG_W_REMOTE_LOWL,
287 		LM90_REG_W_REMOTE_HIGHH,
288 		LM90_REG_W_REMOTE_HIGHL,
289 		LM90_REG_W_REMOTE_OFFSH,
290 		LM90_REG_W_REMOTE_OFFSL,
291 	};
292 
293 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
294 	struct i2c_client *client = to_i2c_client(dev);
295 	struct lm90_data *data = i2c_get_clientdata(client);
296 	long val = simple_strtol(buf, NULL, 10);
297 	int nr = attr->index;
298 
299 	mutex_lock(&data->update_lock);
300 	if (data->kind == adt7461)
301 		data->temp11[nr] = TEMP2_TO_REG_ADT7461(val);
302 	else
303 		data->temp11[nr] = TEMP2_TO_REG(val);
304 	i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2],
305 				  data->temp11[nr] >> 8);
306 	i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2 + 1],
307 				  data->temp11[nr] & 0xff);
308 	mutex_unlock(&data->update_lock);
309 	return count;
310 }
311 
312 static ssize_t show_temphyst(struct device *dev, struct device_attribute *devattr,
313 			     char *buf)
314 {
315 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
316 	struct lm90_data *data = lm90_update_device(dev);
317 	return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index])
318 		       - TEMP1_FROM_REG(data->temp_hyst));
319 }
320 
321 static ssize_t set_temphyst(struct device *dev, struct device_attribute *dummy,
322 			    const char *buf, size_t count)
323 {
324 	struct i2c_client *client = to_i2c_client(dev);
325 	struct lm90_data *data = i2c_get_clientdata(client);
326 	long val = simple_strtol(buf, NULL, 10);
327 	long hyst;
328 
329 	mutex_lock(&data->update_lock);
330 	hyst = TEMP1_FROM_REG(data->temp8[3]) - val;
331 	i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
332 				  HYST_TO_REG(hyst));
333 	mutex_unlock(&data->update_lock);
334 	return count;
335 }
336 
337 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
338 			   char *buf)
339 {
340 	struct lm90_data *data = lm90_update_device(dev);
341 	return sprintf(buf, "%d\n", data->alarms);
342 }
343 
344 static ssize_t show_alarm(struct device *dev, struct device_attribute
345 			  *devattr, char *buf)
346 {
347 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
348 	struct lm90_data *data = lm90_update_device(dev);
349 	int bitnr = attr->index;
350 
351 	return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
352 }
353 
354 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp8, NULL, 0);
355 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp11, NULL, 0);
356 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp8,
357 	set_temp8, 1);
358 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp11,
359 	set_temp11, 1);
360 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp8,
361 	set_temp8, 2);
362 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp11,
363 	set_temp11, 2);
364 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp8,
365 	set_temp8, 3);
366 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp8,
367 	set_temp8, 4);
368 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temphyst,
369 	set_temphyst, 3);
370 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temphyst, NULL, 4);
371 static SENSOR_DEVICE_ATTR(temp2_offset, S_IWUSR | S_IRUGO, show_temp11,
372 	set_temp11, 3);
373 
374 /* Individual alarm files */
375 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
376 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
377 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
378 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
379 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
380 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 5);
381 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
382 /* Raw alarm file for compatibility */
383 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
384 
385 static struct attribute *lm90_attributes[] = {
386 	&sensor_dev_attr_temp1_input.dev_attr.attr,
387 	&sensor_dev_attr_temp2_input.dev_attr.attr,
388 	&sensor_dev_attr_temp1_min.dev_attr.attr,
389 	&sensor_dev_attr_temp2_min.dev_attr.attr,
390 	&sensor_dev_attr_temp1_max.dev_attr.attr,
391 	&sensor_dev_attr_temp2_max.dev_attr.attr,
392 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
393 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
394 	&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
395 	&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
396 
397 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
398 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
399 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
400 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
401 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
402 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
403 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
404 	&dev_attr_alarms.attr,
405 	NULL
406 };
407 
408 static const struct attribute_group lm90_group = {
409 	.attrs = lm90_attributes,
410 };
411 
412 /* pec used for ADM1032 only */
413 static ssize_t show_pec(struct device *dev, struct device_attribute *dummy,
414 			char *buf)
415 {
416 	struct i2c_client *client = to_i2c_client(dev);
417 	return sprintf(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC));
418 }
419 
420 static ssize_t set_pec(struct device *dev, struct device_attribute *dummy,
421 		       const char *buf, size_t count)
422 {
423 	struct i2c_client *client = to_i2c_client(dev);
424 	long val = simple_strtol(buf, NULL, 10);
425 
426 	switch (val) {
427 	case 0:
428 		client->flags &= ~I2C_CLIENT_PEC;
429 		break;
430 	case 1:
431 		client->flags |= I2C_CLIENT_PEC;
432 		break;
433 	default:
434 		return -EINVAL;
435 	}
436 
437 	return count;
438 }
439 
440 static DEVICE_ATTR(pec, S_IWUSR | S_IRUGO, show_pec, set_pec);
441 
442 /*
443  * Real code
444  */
445 
446 /* The ADM1032 supports PEC but not on write byte transactions, so we need
447    to explicitly ask for a transaction without PEC. */
448 static inline s32 adm1032_write_byte(struct i2c_client *client, u8 value)
449 {
450 	return i2c_smbus_xfer(client->adapter, client->addr,
451 			      client->flags & ~I2C_CLIENT_PEC,
452 			      I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
453 }
454 
455 /* It is assumed that client->update_lock is held (unless we are in
456    detection or initialization steps). This matters when PEC is enabled,
457    because we don't want the address pointer to change between the write
458    byte and the read byte transactions. */
459 static int lm90_read_reg(struct i2c_client* client, u8 reg, u8 *value)
460 {
461 	int err;
462 
463  	if (client->flags & I2C_CLIENT_PEC) {
464  		err = adm1032_write_byte(client, reg);
465  		if (err >= 0)
466  			err = i2c_smbus_read_byte(client);
467  	} else
468  		err = i2c_smbus_read_byte_data(client, reg);
469 
470 	if (err < 0) {
471 		dev_warn(&client->dev, "Register %#02x read failed (%d)\n",
472 			 reg, err);
473 		return err;
474 	}
475 	*value = err;
476 
477 	return 0;
478 }
479 
480 static int lm90_attach_adapter(struct i2c_adapter *adapter)
481 {
482 	if (!(adapter->class & I2C_CLASS_HWMON))
483 		return 0;
484 	return i2c_probe(adapter, &addr_data, lm90_detect);
485 }
486 
487 /*
488  * The following function does more than just detection. If detection
489  * succeeds, it also registers the new chip.
490  */
491 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind)
492 {
493 	struct i2c_client *new_client;
494 	struct lm90_data *data;
495 	int err = 0;
496 	const char *name = "";
497 
498 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
499 		goto exit;
500 
501 	if (!(data = kzalloc(sizeof(struct lm90_data), GFP_KERNEL))) {
502 		err = -ENOMEM;
503 		goto exit;
504 	}
505 
506 	/* The common I2C client data is placed right before the
507 	   LM90-specific data. */
508 	new_client = &data->client;
509 	i2c_set_clientdata(new_client, data);
510 	new_client->addr = address;
511 	new_client->adapter = adapter;
512 	new_client->driver = &lm90_driver;
513 	new_client->flags = 0;
514 
515 	/*
516 	 * Now we do the remaining detection. A negative kind means that
517 	 * the driver was loaded with no force parameter (default), so we
518 	 * must both detect and identify the chip. A zero kind means that
519 	 * the driver was loaded with the force parameter, the detection
520 	 * step shall be skipped. A positive kind means that the driver
521 	 * was loaded with the force parameter and a given kind of chip is
522 	 * requested, so both the detection and the identification steps
523 	 * are skipped.
524 	 */
525 
526 	/* Default to an LM90 if forced */
527 	if (kind == 0)
528 		kind = lm90;
529 
530 	if (kind < 0) { /* detection and identification */
531 		int man_id, chip_id, reg_config1, reg_convrate;
532 
533 		if ((man_id = i2c_smbus_read_byte_data(new_client,
534 						LM90_REG_R_MAN_ID)) < 0
535 		 || (chip_id = i2c_smbus_read_byte_data(new_client,
536 						LM90_REG_R_CHIP_ID)) < 0
537 		 || (reg_config1 = i2c_smbus_read_byte_data(new_client,
538 						LM90_REG_R_CONFIG1)) < 0
539 		 || (reg_convrate = i2c_smbus_read_byte_data(new_client,
540 						LM90_REG_R_CONVRATE)) < 0)
541 			goto exit_free;
542 
543 		if ((address == 0x4C || address == 0x4D)
544 		 && man_id == 0x01) { /* National Semiconductor */
545 			int reg_config2;
546 
547 			if ((reg_config2 = i2c_smbus_read_byte_data(new_client,
548 						LM90_REG_R_CONFIG2)) < 0)
549 				goto exit_free;
550 
551 			if ((reg_config1 & 0x2A) == 0x00
552 			 && (reg_config2 & 0xF8) == 0x00
553 			 && reg_convrate <= 0x09) {
554 				if (address == 0x4C
555 				 && (chip_id & 0xF0) == 0x20) { /* LM90 */
556 					kind = lm90;
557 				} else
558 				if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
559 					kind = lm99;
560 				} else
561 				if (address == 0x4C
562 				 && (chip_id & 0xF0) == 0x10) { /* LM86 */
563 					kind = lm86;
564 				}
565 			}
566 		} else
567 		if ((address == 0x4C || address == 0x4D)
568 		 && man_id == 0x41) { /* Analog Devices */
569 			if ((chip_id & 0xF0) == 0x40 /* ADM1032 */
570 			 && (reg_config1 & 0x3F) == 0x00
571 			 && reg_convrate <= 0x0A) {
572 				kind = adm1032;
573 			} else
574 			if (chip_id == 0x51 /* ADT7461 */
575 			 && (reg_config1 & 0x1F) == 0x00 /* check compat mode */
576 			 && reg_convrate <= 0x0A) {
577 				kind = adt7461;
578 			}
579 		} else
580 		if (man_id == 0x4D) { /* Maxim */
581 			/*
582 			 * The MAX6657, MAX6658 and MAX6659 do NOT have a
583 			 * chip_id register. Reading from that address will
584 			 * return the last read value, which in our case is
585 			 * those of the man_id register. Likewise, the config1
586 			 * register seems to lack a low nibble, so the value
587 			 * will be those of the previous read, so in our case
588 			 * those of the man_id register.
589 			 */
590 			if (chip_id == man_id
591 			 && (address == 0x4C || address == 0x4D)
592 			 && (reg_config1 & 0x1F) == (man_id & 0x0F)
593 			 && reg_convrate <= 0x09) {
594 			 	kind = max6657;
595 			} else
596 			/* The chip_id register of the MAX6680 and MAX6681
597 			 * holds the revision of the chip.
598 			 * the lowest bit of the config1 register is unused
599 			 * and should return zero when read, so should the
600 			 * second to last bit of config1 (software reset)
601 			 */
602 			if (chip_id == 0x01
603 			 && (reg_config1 & 0x03) == 0x00
604 			 && reg_convrate <= 0x07) {
605 			 	kind = max6680;
606 			}
607 		}
608 
609 		if (kind <= 0) { /* identification failed */
610 			dev_info(&adapter->dev,
611 			    "Unsupported chip (man_id=0x%02X, "
612 			    "chip_id=0x%02X).\n", man_id, chip_id);
613 			goto exit_free;
614 		}
615 	}
616 
617 	if (kind == lm90) {
618 		name = "lm90";
619 	} else if (kind == adm1032) {
620 		name = "adm1032";
621 		/* The ADM1032 supports PEC, but only if combined
622 		   transactions are not used. */
623 		if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
624 			new_client->flags |= I2C_CLIENT_PEC;
625 	} else if (kind == lm99) {
626 		name = "lm99";
627 	} else if (kind == lm86) {
628 		name = "lm86";
629 	} else if (kind == max6657) {
630 		name = "max6657";
631 	} else if (kind == max6680) {
632 		name = "max6680";
633 	} else if (kind == adt7461) {
634 		name = "adt7461";
635 	}
636 
637 	/* We can fill in the remaining client fields */
638 	strlcpy(new_client->name, name, I2C_NAME_SIZE);
639 	data->valid = 0;
640 	data->kind = kind;
641 	mutex_init(&data->update_lock);
642 
643 	/* Tell the I2C layer a new client has arrived */
644 	if ((err = i2c_attach_client(new_client)))
645 		goto exit_free;
646 
647 	/* Initialize the LM90 chip */
648 	lm90_init_client(new_client);
649 
650 	/* Register sysfs hooks */
651 	if ((err = sysfs_create_group(&new_client->dev.kobj, &lm90_group)))
652 		goto exit_detach;
653 	if (new_client->flags & I2C_CLIENT_PEC) {
654 		if ((err = device_create_file(&new_client->dev,
655 					      &dev_attr_pec)))
656 			goto exit_remove_files;
657 	}
658 	if (data->kind != max6657) {
659 		if ((err = device_create_file(&new_client->dev,
660 				&sensor_dev_attr_temp2_offset.dev_attr)))
661 			goto exit_remove_files;
662 	}
663 
664 	data->hwmon_dev = hwmon_device_register(&new_client->dev);
665 	if (IS_ERR(data->hwmon_dev)) {
666 		err = PTR_ERR(data->hwmon_dev);
667 		goto exit_remove_files;
668 	}
669 
670 	return 0;
671 
672 exit_remove_files:
673 	sysfs_remove_group(&new_client->dev.kobj, &lm90_group);
674 	device_remove_file(&new_client->dev, &dev_attr_pec);
675 exit_detach:
676 	i2c_detach_client(new_client);
677 exit_free:
678 	kfree(data);
679 exit:
680 	return err;
681 }
682 
683 static void lm90_init_client(struct i2c_client *client)
684 {
685 	u8 config, config_orig;
686 	struct lm90_data *data = i2c_get_clientdata(client);
687 
688 	/*
689 	 * Start the conversions.
690 	 */
691 	i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE,
692 				  5); /* 2 Hz */
693 	if (lm90_read_reg(client, LM90_REG_R_CONFIG1, &config) < 0) {
694 		dev_warn(&client->dev, "Initialization failed!\n");
695 		return;
696 	}
697 	config_orig = config;
698 
699 	/*
700 	 * Put MAX6680/MAX8881 into extended resolution (bit 0x10,
701 	 * 0.125 degree resolution) and range (0x08, extend range
702 	 * to -64 degree) mode for the remote temperature sensor.
703 	 */
704 	if (data->kind == max6680) {
705 		config |= 0x18;
706 	}
707 
708 	config &= 0xBF;	/* run */
709 	if (config != config_orig) /* Only write if changed */
710 		i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, config);
711 }
712 
713 static int lm90_detach_client(struct i2c_client *client)
714 {
715 	struct lm90_data *data = i2c_get_clientdata(client);
716 	int err;
717 
718 	hwmon_device_unregister(data->hwmon_dev);
719 	sysfs_remove_group(&client->dev.kobj, &lm90_group);
720 	device_remove_file(&client->dev, &dev_attr_pec);
721 	if (data->kind != max6657)
722 		device_remove_file(&client->dev,
723 				   &sensor_dev_attr_temp2_offset.dev_attr);
724 
725 	if ((err = i2c_detach_client(client)))
726 		return err;
727 
728 	kfree(data);
729 	return 0;
730 }
731 
732 static struct lm90_data *lm90_update_device(struct device *dev)
733 {
734 	struct i2c_client *client = to_i2c_client(dev);
735 	struct lm90_data *data = i2c_get_clientdata(client);
736 
737 	mutex_lock(&data->update_lock);
738 
739 	if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
740 		u8 oldh, newh, l;
741 
742 		dev_dbg(&client->dev, "Updating lm90 data.\n");
743 		lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP, &data->temp8[0]);
744 		lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[1]);
745 		lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH, &data->temp8[2]);
746 		lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT, &data->temp8[3]);
747 		lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT, &data->temp8[4]);
748 		lm90_read_reg(client, LM90_REG_R_TCRIT_HYST, &data->temp_hyst);
749 
750 		/*
751 		 * There is a trick here. We have to read two registers to
752 		 * have the remote sensor temperature, but we have to beware
753 		 * a conversion could occur inbetween the readings. The
754 		 * datasheet says we should either use the one-shot
755 		 * conversion register, which we don't want to do (disables
756 		 * hardware monitoring) or monitor the busy bit, which is
757 		 * impossible (we can't read the values and monitor that bit
758 		 * at the exact same time). So the solution used here is to
759 		 * read the high byte once, then the low byte, then the high
760 		 * byte again. If the new high byte matches the old one,
761 		 * then we have a valid reading. Else we have to read the low
762 		 * byte again, and now we believe we have a correct reading.
763 		 */
764 		if (lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &oldh) == 0
765 		 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0
766 		 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &newh) == 0
767 		 && (newh == oldh
768 		  || lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0))
769 			data->temp11[0] = (newh << 8) | l;
770 
771 		if (lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &newh) == 0
772 		 && lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL, &l) == 0)
773 			data->temp11[1] = (newh << 8) | l;
774 		if (lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &newh) == 0
775 		 && lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL, &l) == 0)
776 			data->temp11[2] = (newh << 8) | l;
777 		if (data->kind != max6657) {
778 			if (lm90_read_reg(client, LM90_REG_R_REMOTE_OFFSH,
779 					  &newh) == 0
780 			 && lm90_read_reg(client, LM90_REG_R_REMOTE_OFFSL,
781 					  &l) == 0)
782 				data->temp11[3] = (newh << 8) | l;
783 		}
784 		lm90_read_reg(client, LM90_REG_R_STATUS, &data->alarms);
785 
786 		data->last_updated = jiffies;
787 		data->valid = 1;
788 	}
789 
790 	mutex_unlock(&data->update_lock);
791 
792 	return data;
793 }
794 
795 static int __init sensors_lm90_init(void)
796 {
797 	return i2c_add_driver(&lm90_driver);
798 }
799 
800 static void __exit sensors_lm90_exit(void)
801 {
802 	i2c_del_driver(&lm90_driver);
803 }
804 
805 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
806 MODULE_DESCRIPTION("LM90/ADM1032 driver");
807 MODULE_LICENSE("GPL");
808 
809 module_init(sensors_lm90_init);
810 module_exit(sensors_lm90_exit);
811