xref: /openbmc/linux/drivers/hwmon/adm9240.c (revision a1e58bbd)
1 /*
2  * adm9240.c	Part of lm_sensors, Linux kernel modules for hardware
3  * 		monitoring
4  *
5  * Copyright (C) 1999	Frodo Looijaard <frodol@dds.nl>
6  *			Philip Edelbrock <phil@netroedge.com>
7  * Copyright (C) 2003	Michiel Rook <michiel@grendelproject.nl>
8  * Copyright (C) 2005	Grant Coady <gcoady.lk@gmail.com> with valuable
9  * 				guidance from Jean Delvare
10  *
11  * Driver supports	Analog Devices		ADM9240
12  *			Dallas Semiconductor	DS1780
13  *			National Semiconductor	LM81
14  *
15  * ADM9240 is the reference, DS1780 and LM81 are register compatibles
16  *
17  * Voltage	Six inputs are scaled by chip, VID also reported
18  * Temperature	Chip temperature to 0.5'C, maximum and max_hysteris
19  * Fans		2 fans, low speed alarm, automatic fan clock divider
20  * Alarms	16-bit map of active alarms
21  * Analog Out	0..1250 mV output
22  *
23  * Chassis Intrusion: clear CI latch with 'echo 1 > chassis_clear'
24  *
25  * Test hardware: Intel SE440BX-2 desktop motherboard --Grant
26  *
27  * LM81 extended temp reading not implemented
28  *
29  * This program is free software; you can redistribute it and/or modify
30  * it under the terms of the GNU General Public License as published by
31  * the Free Software Foundation; either version 2 of the License, or
32  * (at your option) any later version.
33  *
34  * This program is distributed in the hope that it will be useful,
35  * but WITHOUT ANY WARRANTY; without even the implied warranty of
36  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
37  * GNU General Public License for more details.
38  *
39  * You should have received a copy of the GNU General Public License
40  * along with this program; if not, write to the Free Software
41  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
42  */
43 
44 #include <linux/init.h>
45 #include <linux/module.h>
46 #include <linux/slab.h>
47 #include <linux/i2c.h>
48 #include <linux/hwmon-sysfs.h>
49 #include <linux/hwmon.h>
50 #include <linux/hwmon-vid.h>
51 #include <linux/err.h>
52 #include <linux/mutex.h>
53 
54 /* Addresses to scan */
55 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
56 					I2C_CLIENT_END };
57 
58 /* Insmod parameters */
59 I2C_CLIENT_INSMOD_3(adm9240, ds1780, lm81);
60 
61 /* ADM9240 registers */
62 #define ADM9240_REG_MAN_ID		0x3e
63 #define ADM9240_REG_DIE_REV		0x3f
64 #define ADM9240_REG_CONFIG		0x40
65 
66 #define ADM9240_REG_IN(nr)		(0x20 + (nr))   /* 0..5 */
67 #define ADM9240_REG_IN_MAX(nr)		(0x2b + (nr) * 2)
68 #define ADM9240_REG_IN_MIN(nr)		(0x2c + (nr) * 2)
69 #define ADM9240_REG_FAN(nr)		(0x28 + (nr))   /* 0..1 */
70 #define ADM9240_REG_FAN_MIN(nr)		(0x3b + (nr))
71 #define ADM9240_REG_INT(nr)		(0x41 + (nr))
72 #define ADM9240_REG_INT_MASK(nr)	(0x43 + (nr))
73 #define ADM9240_REG_TEMP		0x27
74 #define ADM9240_REG_TEMP_MAX(nr)	(0x39 + (nr)) /* 0, 1 = high, hyst */
75 #define ADM9240_REG_ANALOG_OUT		0x19
76 #define ADM9240_REG_CHASSIS_CLEAR	0x46
77 #define ADM9240_REG_VID_FAN_DIV		0x47
78 #define ADM9240_REG_I2C_ADDR		0x48
79 #define ADM9240_REG_VID4		0x49
80 #define ADM9240_REG_TEMP_CONF		0x4b
81 
82 /* generalised scaling with integer rounding */
83 static inline int SCALE(long val, int mul, int div)
84 {
85 	if (val < 0)
86 		return (val * mul - div / 2) / div;
87 	else
88 		return (val * mul + div / 2) / div;
89 }
90 
91 /* adm9240 internally scales voltage measurements */
92 static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };
93 
94 static inline unsigned int IN_FROM_REG(u8 reg, int n)
95 {
96 	return SCALE(reg, nom_mv[n], 192);
97 }
98 
99 static inline u8 IN_TO_REG(unsigned long val, int n)
100 {
101 	return SENSORS_LIMIT(SCALE(val, 192, nom_mv[n]), 0, 255);
102 }
103 
104 /* temperature range: -40..125, 127 disables temperature alarm */
105 static inline s8 TEMP_TO_REG(long val)
106 {
107 	return SENSORS_LIMIT(SCALE(val, 1, 1000), -40, 127);
108 }
109 
110 /* two fans, each with low fan speed limit */
111 static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
112 {
113 	if (!reg) /* error */
114 		return -1;
115 
116 	if (reg == 255)
117 		return 0;
118 
119 	return SCALE(1350000, 1, reg * div);
120 }
121 
122 /* analog out 0..1250mV */
123 static inline u8 AOUT_TO_REG(unsigned long val)
124 {
125 	return SENSORS_LIMIT(SCALE(val, 255, 1250), 0, 255);
126 }
127 
128 static inline unsigned int AOUT_FROM_REG(u8 reg)
129 {
130 	return SCALE(reg, 1250, 255);
131 }
132 
133 static int adm9240_attach_adapter(struct i2c_adapter *adapter);
134 static int adm9240_detect(struct i2c_adapter *adapter, int address, int kind);
135 static void adm9240_init_client(struct i2c_client *client);
136 static int adm9240_detach_client(struct i2c_client *client);
137 static struct adm9240_data *adm9240_update_device(struct device *dev);
138 
139 /* driver data */
140 static struct i2c_driver adm9240_driver = {
141 	.driver = {
142 		.name	= "adm9240",
143 	},
144 	.attach_adapter	= adm9240_attach_adapter,
145 	.detach_client	= adm9240_detach_client,
146 };
147 
148 /* per client data */
149 struct adm9240_data {
150 	enum chips type;
151 	struct i2c_client client;
152 	struct device *hwmon_dev;
153 	struct mutex update_lock;
154 	char valid;
155 	unsigned long last_updated_measure;
156 	unsigned long last_updated_config;
157 
158 	u8 in[6];		/* ro	in0_input */
159 	u8 in_max[6];		/* rw	in0_max */
160 	u8 in_min[6];		/* rw	in0_min */
161 	u8 fan[2];		/* ro	fan1_input */
162 	u8 fan_min[2];		/* rw	fan1_min */
163 	u8 fan_div[2];		/* rw	fan1_div, read-only accessor */
164 	s16 temp;		/* ro	temp1_input, 9-bit sign-extended */
165 	s8 temp_max[2];		/* rw	0 -> temp_max, 1 -> temp_max_hyst */
166 	u16 alarms;		/* ro	alarms */
167 	u8 aout;		/* rw	aout_output */
168 	u8 vid;			/* ro	vid */
169 	u8 vrm;			/* --	vrm set on startup, no accessor */
170 };
171 
172 /*** sysfs accessors ***/
173 
174 /* temperature */
175 static ssize_t show_temp(struct device *dev, struct device_attribute *dummy,
176 		char *buf)
177 {
178 	struct adm9240_data *data = adm9240_update_device(dev);
179 	return sprintf(buf, "%d\n", data->temp * 500); /* 9-bit value */
180 }
181 
182 static ssize_t show_max(struct device *dev, struct device_attribute *devattr,
183 		char *buf)
184 {
185 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
186 	struct adm9240_data *data = adm9240_update_device(dev);
187 	return sprintf(buf, "%d\n", data->temp_max[attr->index] * 1000);
188 }
189 
190 static ssize_t set_max(struct device *dev, struct device_attribute *devattr,
191 		const char *buf, size_t count)
192 {
193 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
194 	struct i2c_client *client = to_i2c_client(dev);
195 	struct adm9240_data *data = i2c_get_clientdata(client);
196 	long val = simple_strtol(buf, NULL, 10);
197 
198 	mutex_lock(&data->update_lock);
199 	data->temp_max[attr->index] = TEMP_TO_REG(val);
200 	i2c_smbus_write_byte_data(client, ADM9240_REG_TEMP_MAX(attr->index),
201 			data->temp_max[attr->index]);
202 	mutex_unlock(&data->update_lock);
203 	return count;
204 }
205 
206 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
207 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
208 		show_max, set_max, 0);
209 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
210 		show_max, set_max, 1);
211 
212 /* voltage */
213 static ssize_t show_in(struct device *dev, struct device_attribute *devattr,
214 		char *buf)
215 {
216 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
217 	struct adm9240_data *data = adm9240_update_device(dev);
218 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[attr->index],
219 				attr->index));
220 }
221 
222 static ssize_t show_in_min(struct device *dev,
223 		struct device_attribute *devattr, char *buf)
224 {
225 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
226 	struct adm9240_data *data = adm9240_update_device(dev);
227 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[attr->index],
228 				attr->index));
229 }
230 
231 static ssize_t show_in_max(struct device *dev,
232 		struct device_attribute *devattr, char *buf)
233 {
234 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
235 	struct adm9240_data *data = adm9240_update_device(dev);
236 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[attr->index],
237 				attr->index));
238 }
239 
240 static ssize_t set_in_min(struct device *dev,
241 		struct device_attribute *devattr,
242 		const char *buf, size_t count)
243 {
244 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
245 	struct i2c_client *client = to_i2c_client(dev);
246 	struct adm9240_data *data = i2c_get_clientdata(client);
247 	unsigned long val = simple_strtoul(buf, NULL, 10);
248 
249 	mutex_lock(&data->update_lock);
250 	data->in_min[attr->index] = IN_TO_REG(val, attr->index);
251 	i2c_smbus_write_byte_data(client, ADM9240_REG_IN_MIN(attr->index),
252 			data->in_min[attr->index]);
253 	mutex_unlock(&data->update_lock);
254 	return count;
255 }
256 
257 static ssize_t set_in_max(struct device *dev,
258 		struct device_attribute *devattr,
259 		const char *buf, size_t count)
260 {
261 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
262 	struct i2c_client *client = to_i2c_client(dev);
263 	struct adm9240_data *data = i2c_get_clientdata(client);
264 	unsigned long val = simple_strtoul(buf, NULL, 10);
265 
266 	mutex_lock(&data->update_lock);
267 	data->in_max[attr->index] = IN_TO_REG(val, attr->index);
268 	i2c_smbus_write_byte_data(client, ADM9240_REG_IN_MAX(attr->index),
269 			data->in_max[attr->index]);
270 	mutex_unlock(&data->update_lock);
271 	return count;
272 }
273 
274 #define vin(nr)							\
275 static SENSOR_DEVICE_ATTR(in##nr##_input, S_IRUGO, 		\
276 		show_in, NULL, nr);				\
277 static SENSOR_DEVICE_ATTR(in##nr##_min, S_IRUGO | S_IWUSR,	\
278 		show_in_min, set_in_min, nr);			\
279 static SENSOR_DEVICE_ATTR(in##nr##_max, S_IRUGO | S_IWUSR,	\
280 		show_in_max, set_in_max, nr);
281 
282 vin(0);
283 vin(1);
284 vin(2);
285 vin(3);
286 vin(4);
287 vin(5);
288 
289 /* fans */
290 static ssize_t show_fan(struct device *dev,
291 		struct device_attribute *devattr, char *buf)
292 {
293 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
294 	struct adm9240_data *data = adm9240_update_device(dev);
295 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
296 				1 << data->fan_div[attr->index]));
297 }
298 
299 static ssize_t show_fan_min(struct device *dev,
300 		struct device_attribute *devattr, char *buf)
301 {
302 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
303 	struct adm9240_data *data = adm9240_update_device(dev);
304 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[attr->index],
305 				1 << data->fan_div[attr->index]));
306 }
307 
308 static ssize_t show_fan_div(struct device *dev,
309 		struct device_attribute *devattr, char *buf)
310 {
311 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
312 	struct adm9240_data *data = adm9240_update_device(dev);
313 	return sprintf(buf, "%d\n", 1 << data->fan_div[attr->index]);
314 }
315 
316 /* write new fan div, callers must hold data->update_lock */
317 static void adm9240_write_fan_div(struct i2c_client *client, int nr,
318 		u8 fan_div)
319 {
320 	u8 reg, old, shift = (nr + 2) * 2;
321 
322 	reg = i2c_smbus_read_byte_data(client, ADM9240_REG_VID_FAN_DIV);
323 	old = (reg >> shift) & 3;
324 	reg &= ~(3 << shift);
325 	reg |= (fan_div << shift);
326 	i2c_smbus_write_byte_data(client, ADM9240_REG_VID_FAN_DIV, reg);
327 	dev_dbg(&client->dev, "fan%d clock divider changed from %u "
328 			"to %u\n", nr + 1, 1 << old, 1 << fan_div);
329 }
330 
331 /*
332  * set fan speed low limit:
333  *
334  * - value is zero: disable fan speed low limit alarm
335  *
336  * - value is below fan speed measurement range: enable fan speed low
337  *   limit alarm to be asserted while fan speed too slow to measure
338  *
339  * - otherwise: select fan clock divider to suit fan speed low limit,
340  *   measurement code may adjust registers to ensure fan speed reading
341  */
342 static ssize_t set_fan_min(struct device *dev,
343 		struct device_attribute *devattr,
344 		const char *buf, size_t count)
345 {
346 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
347 	struct i2c_client *client = to_i2c_client(dev);
348 	struct adm9240_data *data = i2c_get_clientdata(client);
349 	unsigned long val = simple_strtoul(buf, NULL, 10);
350 	int nr = attr->index;
351 	u8 new_div;
352 
353 	mutex_lock(&data->update_lock);
354 
355 	if (!val) {
356 		data->fan_min[nr] = 255;
357 		new_div = data->fan_div[nr];
358 
359 		dev_dbg(&client->dev, "fan%u low limit set disabled\n",
360 				nr + 1);
361 
362 	} else if (val < 1350000 / (8 * 254)) {
363 		new_div = 3;
364 		data->fan_min[nr] = 254;
365 
366 		dev_dbg(&client->dev, "fan%u low limit set minimum %u\n",
367 				nr + 1, FAN_FROM_REG(254, 1 << new_div));
368 
369 	} else {
370 		unsigned int new_min = 1350000 / val;
371 
372 		new_div = 0;
373 		while (new_min > 192 && new_div < 3) {
374 			new_div++;
375 			new_min /= 2;
376 		}
377 		if (!new_min) /* keep > 0 */
378 			new_min++;
379 
380 		data->fan_min[nr] = new_min;
381 
382 		dev_dbg(&client->dev, "fan%u low limit set fan speed %u\n",
383 				nr + 1, FAN_FROM_REG(new_min, 1 << new_div));
384 	}
385 
386 	if (new_div != data->fan_div[nr]) {
387 		data->fan_div[nr] = new_div;
388 		adm9240_write_fan_div(client, nr, new_div);
389 	}
390 	i2c_smbus_write_byte_data(client, ADM9240_REG_FAN_MIN(nr),
391 			data->fan_min[nr]);
392 
393 	mutex_unlock(&data->update_lock);
394 	return count;
395 }
396 
397 #define fan(nr)							\
398 static SENSOR_DEVICE_ATTR(fan##nr##_input, S_IRUGO,		\
399 		show_fan, NULL, nr - 1);			\
400 static SENSOR_DEVICE_ATTR(fan##nr##_div, S_IRUGO,		\
401 		show_fan_div, NULL, nr - 1);			\
402 static SENSOR_DEVICE_ATTR(fan##nr##_min, S_IRUGO | S_IWUSR,	\
403 		show_fan_min, set_fan_min, nr - 1);
404 
405 fan(1);
406 fan(2);
407 
408 /* alarms */
409 static ssize_t show_alarms(struct device *dev,
410 		struct device_attribute *attr, char *buf)
411 {
412 	struct adm9240_data *data = adm9240_update_device(dev);
413 	return sprintf(buf, "%u\n", data->alarms);
414 }
415 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
416 
417 static ssize_t show_alarm(struct device *dev,
418 		struct device_attribute *attr, char *buf)
419 {
420 	int bitnr = to_sensor_dev_attr(attr)->index;
421 	struct adm9240_data *data = adm9240_update_device(dev);
422 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
423 }
424 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
425 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
426 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
427 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
428 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
429 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 9);
430 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
431 static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
432 static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
433 
434 /* vid */
435 static ssize_t show_vid(struct device *dev,
436 		struct device_attribute *attr, char *buf)
437 {
438 	struct adm9240_data *data = adm9240_update_device(dev);
439 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
440 }
441 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
442 
443 /* analog output */
444 static ssize_t show_aout(struct device *dev,
445 		struct device_attribute *attr, char *buf)
446 {
447 	struct adm9240_data *data = adm9240_update_device(dev);
448 	return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
449 }
450 
451 static ssize_t set_aout(struct device *dev,
452 		struct device_attribute *attr,
453 		const char *buf, size_t count)
454 {
455 	struct i2c_client *client = to_i2c_client(dev);
456 	struct adm9240_data *data = i2c_get_clientdata(client);
457 	unsigned long val = simple_strtol(buf, NULL, 10);
458 
459 	mutex_lock(&data->update_lock);
460 	data->aout = AOUT_TO_REG(val);
461 	i2c_smbus_write_byte_data(client, ADM9240_REG_ANALOG_OUT, data->aout);
462 	mutex_unlock(&data->update_lock);
463 	return count;
464 }
465 static DEVICE_ATTR(aout_output, S_IRUGO | S_IWUSR, show_aout, set_aout);
466 
467 /* chassis_clear */
468 static ssize_t chassis_clear(struct device *dev,
469 		struct device_attribute *attr,
470 		const char *buf, size_t count)
471 {
472 	struct i2c_client *client = to_i2c_client(dev);
473 	unsigned long val = simple_strtol(buf, NULL, 10);
474 
475 	if (val == 1) {
476 		i2c_smbus_write_byte_data(client,
477 				ADM9240_REG_CHASSIS_CLEAR, 0x80);
478 		dev_dbg(&client->dev, "chassis intrusion latch cleared\n");
479 	}
480 	return count;
481 }
482 static DEVICE_ATTR(chassis_clear, S_IWUSR, NULL, chassis_clear);
483 
484 static struct attribute *adm9240_attributes[] = {
485 	&sensor_dev_attr_in0_input.dev_attr.attr,
486 	&sensor_dev_attr_in0_min.dev_attr.attr,
487 	&sensor_dev_attr_in0_max.dev_attr.attr,
488 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
489 	&sensor_dev_attr_in1_input.dev_attr.attr,
490 	&sensor_dev_attr_in1_min.dev_attr.attr,
491 	&sensor_dev_attr_in1_max.dev_attr.attr,
492 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
493 	&sensor_dev_attr_in2_input.dev_attr.attr,
494 	&sensor_dev_attr_in2_min.dev_attr.attr,
495 	&sensor_dev_attr_in2_max.dev_attr.attr,
496 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
497 	&sensor_dev_attr_in3_input.dev_attr.attr,
498 	&sensor_dev_attr_in3_min.dev_attr.attr,
499 	&sensor_dev_attr_in3_max.dev_attr.attr,
500 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
501 	&sensor_dev_attr_in4_input.dev_attr.attr,
502 	&sensor_dev_attr_in4_min.dev_attr.attr,
503 	&sensor_dev_attr_in4_max.dev_attr.attr,
504 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
505 	&sensor_dev_attr_in5_input.dev_attr.attr,
506 	&sensor_dev_attr_in5_min.dev_attr.attr,
507 	&sensor_dev_attr_in5_max.dev_attr.attr,
508 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
509 	&dev_attr_temp1_input.attr,
510 	&sensor_dev_attr_temp1_max.dev_attr.attr,
511 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
512 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
513 	&sensor_dev_attr_fan1_input.dev_attr.attr,
514 	&sensor_dev_attr_fan1_div.dev_attr.attr,
515 	&sensor_dev_attr_fan1_min.dev_attr.attr,
516 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
517 	&sensor_dev_attr_fan2_input.dev_attr.attr,
518 	&sensor_dev_attr_fan2_div.dev_attr.attr,
519 	&sensor_dev_attr_fan2_min.dev_attr.attr,
520 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
521 	&dev_attr_alarms.attr,
522 	&dev_attr_aout_output.attr,
523 	&dev_attr_chassis_clear.attr,
524 	&dev_attr_cpu0_vid.attr,
525 	NULL
526 };
527 
528 static const struct attribute_group adm9240_group = {
529 	.attrs = adm9240_attributes,
530 };
531 
532 
533 /*** sensor chip detect and driver install ***/
534 
535 static int adm9240_detect(struct i2c_adapter *adapter, int address, int kind)
536 {
537 	struct i2c_client *new_client;
538 	struct adm9240_data *data;
539 	int err = 0;
540 	const char *name = "";
541 	u8 man_id, die_rev;
542 
543 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
544 		goto exit;
545 
546 	if (!(data = kzalloc(sizeof(*data), GFP_KERNEL))) {
547 		err = -ENOMEM;
548 		goto exit;
549 	}
550 
551 	new_client = &data->client;
552 	i2c_set_clientdata(new_client, data);
553 	new_client->addr = address;
554 	new_client->adapter = adapter;
555 	new_client->driver = &adm9240_driver;
556 	new_client->flags = 0;
557 
558 	if (kind == 0) {
559 		kind = adm9240;
560 	}
561 
562 	if (kind < 0) {
563 
564 		/* verify chip: reg address should match i2c address */
565 		if (i2c_smbus_read_byte_data(new_client, ADM9240_REG_I2C_ADDR)
566 				!= address) {
567 			dev_err(&adapter->dev, "detect fail: address match, "
568 					"0x%02x\n", address);
569 			goto exit_free;
570 		}
571 
572 		/* check known chip manufacturer */
573 		man_id = i2c_smbus_read_byte_data(new_client,
574 				ADM9240_REG_MAN_ID);
575 		if (man_id == 0x23) {
576 			kind = adm9240;
577 		} else if (man_id == 0xda) {
578 			kind = ds1780;
579 		} else if (man_id == 0x01) {
580 			kind = lm81;
581 		} else {
582 			dev_err(&adapter->dev, "detect fail: unknown manuf, "
583 					"0x%02x\n", man_id);
584 			goto exit_free;
585 		}
586 
587 		/* successful detect, print chip info */
588 		die_rev = i2c_smbus_read_byte_data(new_client,
589 				ADM9240_REG_DIE_REV);
590 		dev_info(&adapter->dev, "found %s revision %u\n",
591 				man_id == 0x23 ? "ADM9240" :
592 				man_id == 0xda ? "DS1780" : "LM81", die_rev);
593 	}
594 
595 	/* either forced or detected chip kind */
596 	if (kind == adm9240) {
597 		name = "adm9240";
598 	} else if (kind == ds1780) {
599 		name = "ds1780";
600 	} else if (kind == lm81) {
601 		name = "lm81";
602 	}
603 
604 	/* fill in the remaining client fields and attach */
605 	strlcpy(new_client->name, name, I2C_NAME_SIZE);
606 	data->type = kind;
607 	mutex_init(&data->update_lock);
608 
609 	if ((err = i2c_attach_client(new_client)))
610 		goto exit_free;
611 
612 	adm9240_init_client(new_client);
613 
614 	/* populate sysfs filesystem */
615 	if ((err = sysfs_create_group(&new_client->dev.kobj, &adm9240_group)))
616 		goto exit_detach;
617 
618 	data->hwmon_dev = hwmon_device_register(&new_client->dev);
619 	if (IS_ERR(data->hwmon_dev)) {
620 		err = PTR_ERR(data->hwmon_dev);
621 		goto exit_remove;
622 	}
623 
624 	return 0;
625 
626 exit_remove:
627 	sysfs_remove_group(&new_client->dev.kobj, &adm9240_group);
628 exit_detach:
629 	i2c_detach_client(new_client);
630 exit_free:
631 	kfree(data);
632 exit:
633 	return err;
634 }
635 
636 static int adm9240_attach_adapter(struct i2c_adapter *adapter)
637 {
638 	if (!(adapter->class & I2C_CLASS_HWMON))
639 		return 0;
640 	return i2c_probe(adapter, &addr_data, adm9240_detect);
641 }
642 
643 static int adm9240_detach_client(struct i2c_client *client)
644 {
645 	struct adm9240_data *data = i2c_get_clientdata(client);
646 	int err;
647 
648 	hwmon_device_unregister(data->hwmon_dev);
649 	sysfs_remove_group(&client->dev.kobj, &adm9240_group);
650 
651 	if ((err = i2c_detach_client(client)))
652 		return err;
653 
654 	kfree(data);
655 	return 0;
656 }
657 
658 static void adm9240_init_client(struct i2c_client *client)
659 {
660 	struct adm9240_data *data = i2c_get_clientdata(client);
661 	u8 conf = i2c_smbus_read_byte_data(client, ADM9240_REG_CONFIG);
662 	u8 mode = i2c_smbus_read_byte_data(client, ADM9240_REG_TEMP_CONF) & 3;
663 
664 	data->vrm = vid_which_vrm(); /* need this to report vid as mV */
665 
666 	dev_info(&client->dev, "Using VRM: %d.%d\n", data->vrm / 10,
667 			data->vrm % 10);
668 
669 	if (conf & 1) { /* measurement cycle running: report state */
670 
671 		dev_info(&client->dev, "status: config 0x%02x mode %u\n",
672 				conf, mode);
673 
674 	} else { /* cold start: open limits before starting chip */
675 		int i;
676 
677 		for (i = 0; i < 6; i++)
678 		{
679 			i2c_smbus_write_byte_data(client,
680 					ADM9240_REG_IN_MIN(i), 0);
681 			i2c_smbus_write_byte_data(client,
682 					ADM9240_REG_IN_MAX(i), 255);
683 		}
684 		i2c_smbus_write_byte_data(client,
685 				ADM9240_REG_FAN_MIN(0), 255);
686 		i2c_smbus_write_byte_data(client,
687 				ADM9240_REG_FAN_MIN(1), 255);
688 		i2c_smbus_write_byte_data(client,
689 				ADM9240_REG_TEMP_MAX(0), 127);
690 		i2c_smbus_write_byte_data(client,
691 				ADM9240_REG_TEMP_MAX(1), 127);
692 
693 		/* start measurement cycle */
694 		i2c_smbus_write_byte_data(client, ADM9240_REG_CONFIG, 1);
695 
696 		dev_info(&client->dev, "cold start: config was 0x%02x "
697 				"mode %u\n", conf, mode);
698 	}
699 }
700 
701 static struct adm9240_data *adm9240_update_device(struct device *dev)
702 {
703 	struct i2c_client *client = to_i2c_client(dev);
704 	struct adm9240_data *data = i2c_get_clientdata(client);
705 	int i;
706 
707 	mutex_lock(&data->update_lock);
708 
709 	/* minimum measurement cycle: 1.75 seconds */
710 	if (time_after(jiffies, data->last_updated_measure + (HZ * 7 / 4))
711 			|| !data->valid) {
712 
713 		for (i = 0; i < 6; i++) /* read voltages */
714 		{
715 			data->in[i] = i2c_smbus_read_byte_data(client,
716 					ADM9240_REG_IN(i));
717 		}
718 		data->alarms = i2c_smbus_read_byte_data(client,
719 					ADM9240_REG_INT(0)) |
720 					i2c_smbus_read_byte_data(client,
721 					ADM9240_REG_INT(1)) << 8;
722 
723 		/* read temperature: assume temperature changes less than
724 		 * 0.5'C per two measurement cycles thus ignore possible
725 		 * but unlikely aliasing error on lsb reading. --Grant */
726 		data->temp = ((i2c_smbus_read_byte_data(client,
727 					ADM9240_REG_TEMP) << 8) |
728 					i2c_smbus_read_byte_data(client,
729 					ADM9240_REG_TEMP_CONF)) / 128;
730 
731 		for (i = 0; i < 2; i++) /* read fans */
732 		{
733 			data->fan[i] = i2c_smbus_read_byte_data(client,
734 					ADM9240_REG_FAN(i));
735 
736 			/* adjust fan clock divider on overflow */
737 			if (data->valid && data->fan[i] == 255 &&
738 					data->fan_div[i] < 3) {
739 
740 				adm9240_write_fan_div(client, i,
741 						++data->fan_div[i]);
742 
743 				/* adjust fan_min if active, but not to 0 */
744 				if (data->fan_min[i] < 255 &&
745 						data->fan_min[i] >= 2)
746 					data->fan_min[i] /= 2;
747 			}
748 		}
749 		data->last_updated_measure = jiffies;
750 	}
751 
752 	/* minimum config reading cycle: 300 seconds */
753 	if (time_after(jiffies, data->last_updated_config + (HZ * 300))
754 			|| !data->valid) {
755 
756 		for (i = 0; i < 6; i++)
757 		{
758 			data->in_min[i] = i2c_smbus_read_byte_data(client,
759 					ADM9240_REG_IN_MIN(i));
760 			data->in_max[i] = i2c_smbus_read_byte_data(client,
761 					ADM9240_REG_IN_MAX(i));
762 		}
763 		for (i = 0; i < 2; i++)
764 		{
765 			data->fan_min[i] = i2c_smbus_read_byte_data(client,
766 					ADM9240_REG_FAN_MIN(i));
767 		}
768 		data->temp_max[0] = i2c_smbus_read_byte_data(client,
769 				ADM9240_REG_TEMP_MAX(0));
770 		data->temp_max[1] = i2c_smbus_read_byte_data(client,
771 				ADM9240_REG_TEMP_MAX(1));
772 
773 		/* read fan divs and 5-bit VID */
774 		i = i2c_smbus_read_byte_data(client, ADM9240_REG_VID_FAN_DIV);
775 		data->fan_div[0] = (i >> 4) & 3;
776 		data->fan_div[1] = (i >> 6) & 3;
777 		data->vid = i & 0x0f;
778 		data->vid |= (i2c_smbus_read_byte_data(client,
779 					ADM9240_REG_VID4) & 1) << 4;
780 		/* read analog out */
781 		data->aout = i2c_smbus_read_byte_data(client,
782 				ADM9240_REG_ANALOG_OUT);
783 
784 		data->last_updated_config = jiffies;
785 		data->valid = 1;
786 	}
787 	mutex_unlock(&data->update_lock);
788 	return data;
789 }
790 
791 static int __init sensors_adm9240_init(void)
792 {
793 	return i2c_add_driver(&adm9240_driver);
794 }
795 
796 static void __exit sensors_adm9240_exit(void)
797 {
798 	i2c_del_driver(&adm9240_driver);
799 }
800 
801 MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
802 		"Grant Coady <gcoady.lk@gmail.com> and others");
803 MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
804 MODULE_LICENSE("GPL");
805 
806 module_init(sensors_adm9240_init);
807 module_exit(sensors_adm9240_exit);
808 
809