xref: /openbmc/linux/drivers/hwmon/amc6821.c (revision a09d2831)
1 /*
2 	amc6821.c - Part of lm_sensors, Linux kernel modules for hardware
3 	monitoring
4 	Copyright (C) 2009 T. Mertelj <tomaz.mertelj@guest.arnes.si>
5 
6 	Based on max6650.c:
7 	Copyright (C) 2007 Hans J. Koch <hjk@linutronix.de>
8 
9 	This program is free software; you can redistribute it and/or modify
10 	it under the terms of the GNU General Public License as published by
11 	the Free Software Foundation; either version 2 of the License, or
12 	(at your option) any later version.
13 
14 	This program is distributed in the hope that it will be useful,
15 	but WITHOUT ANY WARRANTY; without even the implied warranty of
16 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 	GNU General Public License for more details.
18 
19 	You should have received a copy of the GNU General Public License
20 	along with this program; if not, write to the Free Software
21 	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 */
23 
24 
25 #include <linux/kernel.h>	/* Needed for KERN_INFO */
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/jiffies.h>
30 #include <linux/i2c.h>
31 #include <linux/hwmon.h>
32 #include <linux/hwmon-sysfs.h>
33 #include <linux/err.h>
34 #include <linux/mutex.h>
35 
36 
37 /*
38  * Addresses to scan.
39  */
40 
41 static const unsigned short normal_i2c[] = {0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e,
42 	0x4c, 0x4d, 0x4e, I2C_CLIENT_END};
43 
44 
45 
46 /*
47  * Insmod parameters
48  */
49 
50 static int pwminv = 0;	/*Inverted PWM output. */
51 module_param(pwminv, int, S_IRUGO);
52 
53 static int init = 1; /*Power-on initialization.*/
54 module_param(init, int, S_IRUGO);
55 
56 
57 enum chips { amc6821 };
58 
59 #define AMC6821_REG_DEV_ID 0x3D
60 #define AMC6821_REG_COMP_ID 0x3E
61 #define AMC6821_REG_CONF1 0x00
62 #define AMC6821_REG_CONF2 0x01
63 #define AMC6821_REG_CONF3 0x3F
64 #define AMC6821_REG_CONF4 0x04
65 #define AMC6821_REG_STAT1 0x02
66 #define AMC6821_REG_STAT2 0x03
67 #define AMC6821_REG_TDATA_LOW 0x08
68 #define AMC6821_REG_TDATA_HI 0x09
69 #define AMC6821_REG_LTEMP_HI 0x0A
70 #define AMC6821_REG_RTEMP_HI 0x0B
71 #define AMC6821_REG_LTEMP_LIMIT_MIN 0x15
72 #define AMC6821_REG_LTEMP_LIMIT_MAX 0x14
73 #define AMC6821_REG_RTEMP_LIMIT_MIN 0x19
74 #define AMC6821_REG_RTEMP_LIMIT_MAX 0x18
75 #define AMC6821_REG_LTEMP_CRIT 0x1B
76 #define AMC6821_REG_RTEMP_CRIT 0x1D
77 #define AMC6821_REG_PSV_TEMP 0x1C
78 #define AMC6821_REG_DCY 0x22
79 #define AMC6821_REG_LTEMP_FAN_CTRL 0x24
80 #define AMC6821_REG_RTEMP_FAN_CTRL 0x25
81 #define AMC6821_REG_DCY_LOW_TEMP 0x21
82 
83 #define AMC6821_REG_TACH_LLIMITL 0x10
84 #define AMC6821_REG_TACH_LLIMITH 0x11
85 #define AMC6821_REG_TACH_HLIMITL 0x12
86 #define AMC6821_REG_TACH_HLIMITH 0x13
87 
88 #define AMC6821_CONF1_START 0x01
89 #define AMC6821_CONF1_FAN_INT_EN 0x02
90 #define AMC6821_CONF1_FANIE 0x04
91 #define AMC6821_CONF1_PWMINV 0x08
92 #define AMC6821_CONF1_FAN_FAULT_EN 0x10
93 #define AMC6821_CONF1_FDRC0 0x20
94 #define AMC6821_CONF1_FDRC1 0x40
95 #define AMC6821_CONF1_THERMOVIE 0x80
96 
97 #define AMC6821_CONF2_PWM_EN 0x01
98 #define AMC6821_CONF2_TACH_MODE 0x02
99 #define AMC6821_CONF2_TACH_EN 0x04
100 #define AMC6821_CONF2_RTFIE 0x08
101 #define AMC6821_CONF2_LTOIE 0x10
102 #define AMC6821_CONF2_RTOIE 0x20
103 #define AMC6821_CONF2_PSVIE 0x40
104 #define AMC6821_CONF2_RST 0x80
105 
106 #define AMC6821_CONF3_THERM_FAN_EN 0x80
107 #define AMC6821_CONF3_REV_MASK 0x0F
108 
109 #define AMC6821_CONF4_OVREN 0x10
110 #define AMC6821_CONF4_TACH_FAST 0x20
111 #define AMC6821_CONF4_PSPR 0x40
112 #define AMC6821_CONF4_MODE 0x80
113 
114 #define AMC6821_STAT1_RPM_ALARM 0x01
115 #define AMC6821_STAT1_FANS 0x02
116 #define AMC6821_STAT1_RTH 0x04
117 #define AMC6821_STAT1_RTL 0x08
118 #define AMC6821_STAT1_R_THERM 0x10
119 #define AMC6821_STAT1_RTF 0x20
120 #define AMC6821_STAT1_LTH 0x40
121 #define AMC6821_STAT1_LTL 0x80
122 
123 #define AMC6821_STAT2_RTC 0x08
124 #define AMC6821_STAT2_LTC 0x10
125 #define AMC6821_STAT2_LPSV 0x20
126 #define AMC6821_STAT2_L_THERM 0x40
127 #define AMC6821_STAT2_THERM_IN 0x80
128 
129 enum {IDX_TEMP1_INPUT = 0, IDX_TEMP1_MIN, IDX_TEMP1_MAX,
130 	IDX_TEMP1_CRIT, IDX_TEMP2_INPUT, IDX_TEMP2_MIN,
131 	IDX_TEMP2_MAX, IDX_TEMP2_CRIT,
132 	TEMP_IDX_LEN, };
133 
134 static const u8 temp_reg[] = {AMC6821_REG_LTEMP_HI,
135 			AMC6821_REG_LTEMP_LIMIT_MIN,
136 			AMC6821_REG_LTEMP_LIMIT_MAX,
137 			AMC6821_REG_LTEMP_CRIT,
138 			AMC6821_REG_RTEMP_HI,
139 			AMC6821_REG_RTEMP_LIMIT_MIN,
140 			AMC6821_REG_RTEMP_LIMIT_MAX,
141 			AMC6821_REG_RTEMP_CRIT, };
142 
143 enum {IDX_FAN1_INPUT = 0, IDX_FAN1_MIN, IDX_FAN1_MAX,
144 	FAN1_IDX_LEN, };
145 
146 static const u8 fan_reg_low[] = {AMC6821_REG_TDATA_LOW,
147 			AMC6821_REG_TACH_LLIMITL,
148 			AMC6821_REG_TACH_HLIMITL, };
149 
150 
151 static const u8 fan_reg_hi[] = {AMC6821_REG_TDATA_HI,
152 			AMC6821_REG_TACH_LLIMITH,
153 			AMC6821_REG_TACH_HLIMITH, };
154 
155 static int amc6821_probe(
156 		struct i2c_client *client,
157 		const struct i2c_device_id *id);
158 static int amc6821_detect(
159 		struct i2c_client *client,
160 		struct i2c_board_info *info);
161 static int amc6821_init_client(struct i2c_client *client);
162 static int amc6821_remove(struct i2c_client *client);
163 static struct amc6821_data *amc6821_update_device(struct device *dev);
164 
165 /*
166  * Driver data (common to all clients)
167  */
168 
169 static const struct i2c_device_id amc6821_id[] = {
170 	{ "amc6821", amc6821 },
171 	{ }
172 };
173 
174 MODULE_DEVICE_TABLE(i2c, amc6821_id);
175 
176 static struct i2c_driver amc6821_driver = {
177 	.class = I2C_CLASS_HWMON,
178 	.driver = {
179 		.name	= "amc6821",
180 	},
181 	.probe = amc6821_probe,
182 	.remove = amc6821_remove,
183 	.id_table = amc6821_id,
184 	.detect = amc6821_detect,
185 	.address_list = normal_i2c,
186 };
187 
188 
189 /*
190  * Client data (each client gets its own)
191   */
192 
193 struct amc6821_data {
194 	struct device *hwmon_dev;
195 	struct mutex update_lock;
196 	char valid; /* zero until following fields are valid */
197 	unsigned long last_updated; /* in jiffies */
198 
199 	/* register values */
200 	int temp[TEMP_IDX_LEN];
201 
202 	u16 fan[FAN1_IDX_LEN];
203 	u8 fan1_div;
204 
205 	u8 pwm1;
206 	u8 temp1_auto_point_temp[3];
207 	u8 temp2_auto_point_temp[3];
208 	u8 pwm1_auto_point_pwm[3];
209 	u8 pwm1_enable;
210 	u8 pwm1_auto_channels_temp;
211 
212 	u8 stat1;
213 	u8 stat2;
214 };
215 
216 
217 static ssize_t get_temp(
218 		struct device *dev,
219 		struct device_attribute *devattr,
220 		char *buf)
221 {
222 	struct amc6821_data *data = amc6821_update_device(dev);
223 	int ix = to_sensor_dev_attr(devattr)->index;
224 
225 	return sprintf(buf, "%d\n", data->temp[ix] * 1000);
226 }
227 
228 
229 
230 static ssize_t set_temp(
231 		struct device *dev,
232 		struct device_attribute *attr,
233 		const char *buf,
234 		size_t count)
235 {
236 	struct i2c_client *client = to_i2c_client(dev);
237 	struct amc6821_data *data = i2c_get_clientdata(client);
238 	int ix = to_sensor_dev_attr(attr)->index;
239 	long val;
240 
241 	int ret = strict_strtol(buf, 10, &val);
242 	if (ret)
243 		return ret;
244 	val = SENSORS_LIMIT(val / 1000, -128, 127);
245 
246 	mutex_lock(&data->update_lock);
247 	data->temp[ix] = val;
248 	if (i2c_smbus_write_byte_data(client, temp_reg[ix], data->temp[ix])) {
249 		dev_err(&client->dev, "Register write error, aborting.\n");
250 		count = -EIO;
251 	}
252 	mutex_unlock(&data->update_lock);
253 	return count;
254 }
255 
256 
257 
258 
259 static ssize_t get_temp_alarm(
260 	struct device *dev,
261 	struct device_attribute *devattr,
262 	char *buf)
263 {
264 	struct amc6821_data *data = amc6821_update_device(dev);
265 	int ix = to_sensor_dev_attr(devattr)->index;
266 	u8 flag;
267 
268 	switch (ix) {
269 	case IDX_TEMP1_MIN:
270 		flag = data->stat1 & AMC6821_STAT1_LTL;
271 		break;
272 	case IDX_TEMP1_MAX:
273 		flag = data->stat1 & AMC6821_STAT1_LTH;
274 		break;
275 	case IDX_TEMP1_CRIT:
276 		flag = data->stat2 & AMC6821_STAT2_LTC;
277 		break;
278 	case IDX_TEMP2_MIN:
279 		flag = data->stat1 & AMC6821_STAT1_RTL;
280 		break;
281 	case IDX_TEMP2_MAX:
282 		flag = data->stat1 & AMC6821_STAT1_RTH;
283 		break;
284 	case IDX_TEMP2_CRIT:
285 		flag = data->stat2 & AMC6821_STAT2_RTC;
286 		break;
287 	default:
288 		dev_dbg(dev, "Unknown attr->index (%d).\n", ix);
289 		return -EINVAL;
290 	}
291 	if (flag)
292 		return sprintf(buf, "1");
293 	else
294 		return sprintf(buf, "0");
295 }
296 
297 
298 
299 
300 static ssize_t get_temp2_fault(
301 		struct device *dev,
302 		struct device_attribute *devattr,
303 		char *buf)
304 {
305 	struct amc6821_data *data = amc6821_update_device(dev);
306 	if (data->stat1 & AMC6821_STAT1_RTF)
307 		return sprintf(buf, "1");
308 	else
309 		return sprintf(buf, "0");
310 }
311 
312 static ssize_t get_pwm1(
313 		struct device *dev,
314 		struct device_attribute *devattr,
315 		char *buf)
316 {
317 	struct amc6821_data *data = amc6821_update_device(dev);
318 	return sprintf(buf, "%d\n", data->pwm1);
319 }
320 
321 static ssize_t set_pwm1(
322 		struct device *dev,
323 		struct device_attribute *devattr,
324 		const char *buf,
325 		size_t count)
326 {
327 	struct i2c_client *client = to_i2c_client(dev);
328 	struct amc6821_data *data = i2c_get_clientdata(client);
329 	long val;
330 	int ret = strict_strtol(buf, 10, &val);
331 	if (ret)
332 		return ret;
333 
334 	mutex_lock(&data->update_lock);
335 	data->pwm1 = SENSORS_LIMIT(val , 0, 255);
336 	i2c_smbus_write_byte_data(client, AMC6821_REG_DCY, data->pwm1);
337 	mutex_unlock(&data->update_lock);
338 	return count;
339 }
340 
341 static ssize_t get_pwm1_enable(
342 		struct device *dev,
343 		struct device_attribute *devattr,
344 		char *buf)
345 {
346 	struct amc6821_data *data = amc6821_update_device(dev);
347 	return sprintf(buf, "%d\n", data->pwm1_enable);
348 }
349 
350 static ssize_t set_pwm1_enable(
351 		struct device *dev,
352 		struct device_attribute *attr,
353 		const char *buf,
354 		size_t count)
355 {
356 	struct i2c_client *client = to_i2c_client(dev);
357 	struct amc6821_data *data = i2c_get_clientdata(client);
358 	long val;
359 	int config = strict_strtol(buf, 10, &val);
360 	if (config)
361 		return config;
362 
363 	config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
364 	if (config < 0) {
365 			dev_err(&client->dev,
366 			"Error reading configuration register, aborting.\n");
367 			return -EIO;
368 	}
369 
370 	switch (val) {
371 	case 1:
372 		config &= ~AMC6821_CONF1_FDRC0;
373 		config &= ~AMC6821_CONF1_FDRC1;
374 		break;
375 	case 2:
376 		config &= ~AMC6821_CONF1_FDRC0;
377 		config |= AMC6821_CONF1_FDRC1;
378 		break;
379 	case 3:
380 		config |= AMC6821_CONF1_FDRC0;
381 		config |= AMC6821_CONF1_FDRC1;
382 		break;
383 	default:
384 		return -EINVAL;
385 	}
386 	mutex_lock(&data->update_lock);
387 	if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF1, config)) {
388 			dev_err(&client->dev,
389 			"Configuration register write error, aborting.\n");
390 			count = -EIO;
391 	}
392 	mutex_unlock(&data->update_lock);
393 	return count;
394 }
395 
396 
397 static ssize_t get_pwm1_auto_channels_temp(
398 		struct device *dev,
399 		struct device_attribute *devattr,
400 		char *buf)
401 {
402 	struct amc6821_data *data = amc6821_update_device(dev);
403 	return sprintf(buf, "%d\n", data->pwm1_auto_channels_temp);
404 }
405 
406 
407 static ssize_t get_temp_auto_point_temp(
408 		struct device *dev,
409 		struct device_attribute *devattr,
410 		char *buf)
411 {
412 	int ix = to_sensor_dev_attr_2(devattr)->index;
413 	int nr = to_sensor_dev_attr_2(devattr)->nr;
414 	struct amc6821_data *data = amc6821_update_device(dev);
415 	switch (nr) {
416 	case 1:
417 		return sprintf(buf, "%d\n",
418 			data->temp1_auto_point_temp[ix] * 1000);
419 		break;
420 	case 2:
421 		return sprintf(buf, "%d\n",
422 			data->temp2_auto_point_temp[ix] * 1000);
423 		break;
424 	default:
425 		dev_dbg(dev, "Unknown attr->nr (%d).\n", nr);
426 		return -EINVAL;
427 	}
428 }
429 
430 
431 static ssize_t get_pwm1_auto_point_pwm(
432 		struct device *dev,
433 		struct device_attribute *devattr,
434 		char *buf)
435 {
436 	int ix = to_sensor_dev_attr(devattr)->index;
437 	struct amc6821_data *data = amc6821_update_device(dev);
438 	return sprintf(buf, "%d\n", data->pwm1_auto_point_pwm[ix]);
439 }
440 
441 
442 static inline ssize_t set_slope_register(struct i2c_client *client,
443 		u8 reg,
444 		u8 dpwm,
445 		u8 *ptemp)
446 {
447 	int dt;
448 	u8 tmp;
449 
450 	dt = ptemp[2]-ptemp[1];
451 	for (tmp = 4; tmp > 0; tmp--) {
452 		if (dt * (0x20 >> tmp) >= dpwm)
453 			break;
454 	}
455 	tmp |= (ptemp[1] & 0x7C) << 1;
456 	if (i2c_smbus_write_byte_data(client,
457 			reg, tmp)) {
458 		dev_err(&client->dev, "Register write error, aborting.\n");
459 		return -EIO;
460 	}
461 	return 0;
462 }
463 
464 
465 
466 static ssize_t set_temp_auto_point_temp(
467 		struct device *dev,
468 		struct device_attribute *attr,
469 		const char *buf,
470 		size_t count)
471 {
472 	struct i2c_client *client = to_i2c_client(dev);
473 	struct amc6821_data *data = amc6821_update_device(dev);
474 	int ix = to_sensor_dev_attr_2(attr)->index;
475 	int nr = to_sensor_dev_attr_2(attr)->nr;
476 	u8 *ptemp;
477 	u8 reg;
478 	int dpwm;
479 	long val;
480 	int ret = strict_strtol(buf, 10, &val);
481 	if (ret)
482 		return ret;
483 
484 	switch (nr) {
485 	case 1:
486 		ptemp = data->temp1_auto_point_temp;
487 		reg = AMC6821_REG_LTEMP_FAN_CTRL;
488 		break;
489 	case 2:
490 		ptemp = data->temp2_auto_point_temp;
491 		reg = AMC6821_REG_RTEMP_FAN_CTRL;
492 		break;
493 	default:
494 		dev_dbg(dev, "Unknown attr->nr (%d).\n", nr);
495 		return -EINVAL;
496 	}
497 
498 	data->valid = 0;
499 	mutex_lock(&data->update_lock);
500 	switch (ix) {
501 	case 0:
502 		ptemp[0] = SENSORS_LIMIT(val / 1000, 0,
503 				data->temp1_auto_point_temp[1]);
504 		ptemp[0] = SENSORS_LIMIT(ptemp[0], 0,
505 				data->temp2_auto_point_temp[1]);
506 		ptemp[0] = SENSORS_LIMIT(ptemp[0], 0, 63);
507 		if (i2c_smbus_write_byte_data(
508 					client,
509 					AMC6821_REG_PSV_TEMP,
510 					ptemp[0])) {
511 				dev_err(&client->dev,
512 					"Register write error, aborting.\n");
513 				count = -EIO;
514 		}
515 		goto EXIT;
516 		break;
517 	case 1:
518 		ptemp[1] = SENSORS_LIMIT(
519 					val / 1000,
520 					(ptemp[0] & 0x7C) + 4,
521 					124);
522 		ptemp[1] &= 0x7C;
523 		ptemp[2] = SENSORS_LIMIT(
524 					ptemp[2], ptemp[1] + 1,
525 					255);
526 		break;
527 	case 2:
528 		ptemp[2] = SENSORS_LIMIT(
529 					val / 1000,
530 					ptemp[1]+1,
531 					255);
532 		break;
533 	default:
534 		dev_dbg(dev, "Unknown attr->index (%d).\n", ix);
535 		count = -EINVAL;
536 		goto EXIT;
537 	}
538 	dpwm = data->pwm1_auto_point_pwm[2] - data->pwm1_auto_point_pwm[1];
539 	if (set_slope_register(client, reg, dpwm, ptemp))
540 		count = -EIO;
541 
542 EXIT:
543 	mutex_unlock(&data->update_lock);
544 	return count;
545 }
546 
547 
548 
549 static ssize_t set_pwm1_auto_point_pwm(
550 		struct device *dev,
551 		struct device_attribute *attr,
552 		const char *buf,
553 		size_t count)
554 {
555 	struct i2c_client *client = to_i2c_client(dev);
556 	struct amc6821_data *data = i2c_get_clientdata(client);
557 	int dpwm;
558 	long val;
559 	int ret = strict_strtol(buf, 10, &val);
560 	if (ret)
561 		return ret;
562 
563 	mutex_lock(&data->update_lock);
564 	data->pwm1_auto_point_pwm[1] = SENSORS_LIMIT(val, 0, 254);
565 	if (i2c_smbus_write_byte_data(client, AMC6821_REG_DCY_LOW_TEMP,
566 			data->pwm1_auto_point_pwm[1])) {
567 		dev_err(&client->dev, "Register write error, aborting.\n");
568 		count = -EIO;
569 		goto EXIT;
570 	}
571 	dpwm = data->pwm1_auto_point_pwm[2] - data->pwm1_auto_point_pwm[1];
572 	if (set_slope_register(client, AMC6821_REG_LTEMP_FAN_CTRL, dpwm,
573 			data->temp1_auto_point_temp)) {
574 		count = -EIO;
575 		goto EXIT;
576 	}
577 	if (set_slope_register(client, AMC6821_REG_RTEMP_FAN_CTRL, dpwm,
578 			data->temp2_auto_point_temp)) {
579 		count = -EIO;
580 		goto EXIT;
581 	}
582 
583 EXIT:
584 	data->valid = 0;
585 	mutex_unlock(&data->update_lock);
586 	return count;
587 }
588 
589 static ssize_t get_fan(
590 		struct device *dev,
591 		struct device_attribute *devattr,
592 		char *buf)
593 {
594 	struct amc6821_data *data = amc6821_update_device(dev);
595 	int ix = to_sensor_dev_attr(devattr)->index;
596 	if (0 == data->fan[ix])
597 		return sprintf(buf, "0");
598 	return sprintf(buf, "%d\n", (int)(6000000 / data->fan[ix]));
599 }
600 
601 
602 
603 static ssize_t get_fan1_fault(
604 		struct device *dev,
605 		struct device_attribute *devattr,
606 		char *buf)
607 {
608 	struct amc6821_data *data = amc6821_update_device(dev);
609 	if (data->stat1 & AMC6821_STAT1_FANS)
610 		return sprintf(buf, "1");
611 	else
612 		return sprintf(buf, "0");
613 }
614 
615 
616 
617 static ssize_t set_fan(
618 		struct device *dev,
619 		struct device_attribute *attr,
620 		const char *buf, size_t count)
621 {
622 	struct i2c_client *client = to_i2c_client(dev);
623 	struct amc6821_data *data = i2c_get_clientdata(client);
624 	long val;
625 	int ix = to_sensor_dev_attr(attr)->index;
626 	int ret = strict_strtol(buf, 10, &val);
627 	if (ret)
628 		return ret;
629 	val = 1 > val ? 0xFFFF : 6000000/val;
630 
631 	mutex_lock(&data->update_lock);
632 	data->fan[ix] = (u16) SENSORS_LIMIT(val, 1, 0xFFFF);
633 	if (i2c_smbus_write_byte_data(client, fan_reg_low[ix],
634 			data->fan[ix] & 0xFF)) {
635 		dev_err(&client->dev, "Register write error, aborting.\n");
636 		count = -EIO;
637 		goto EXIT;
638 	}
639 	if (i2c_smbus_write_byte_data(client,
640 			fan_reg_hi[ix], data->fan[ix] >> 8)) {
641 		dev_err(&client->dev, "Register write error, aborting.\n");
642 		count = -EIO;
643 	}
644 EXIT:
645 	mutex_unlock(&data->update_lock);
646 	return count;
647 }
648 
649 
650 
651 static ssize_t get_fan1_div(
652 		struct device *dev,
653 		struct device_attribute *devattr,
654 		char *buf)
655 {
656 	struct amc6821_data *data = amc6821_update_device(dev);
657 	return sprintf(buf, "%d\n", data->fan1_div);
658 }
659 
660 static ssize_t set_fan1_div(
661 		struct device *dev,
662 		struct device_attribute *attr,
663 		const char *buf, size_t count)
664 {
665 	struct i2c_client *client = to_i2c_client(dev);
666 	struct amc6821_data *data = i2c_get_clientdata(client);
667 	long val;
668 	int config = strict_strtol(buf, 10, &val);
669 	if (config)
670 		return config;
671 
672 	config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF4);
673 	if (config < 0) {
674 		dev_err(&client->dev,
675 			"Error reading configuration register, aborting.\n");
676 		return -EIO;
677 	}
678 	mutex_lock(&data->update_lock);
679 	switch (val) {
680 	case 2:
681 		config &= ~AMC6821_CONF4_PSPR;
682 		data->fan1_div = 2;
683 		break;
684 	case 4:
685 		config |= AMC6821_CONF4_PSPR;
686 		data->fan1_div = 4;
687 		break;
688 	default:
689 		mutex_unlock(&data->update_lock);
690 		count = -EINVAL;
691 		goto EXIT;
692 	}
693 	if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF4, config)) {
694 		dev_err(&client->dev,
695 			"Configuration register write error, aborting.\n");
696 		count = -EIO;
697 	}
698 EXIT:
699 	mutex_unlock(&data->update_lock);
700 	return count;
701 }
702 
703 
704 
705 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
706 	get_temp, NULL, IDX_TEMP1_INPUT);
707 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, get_temp,
708 	set_temp, IDX_TEMP1_MIN);
709 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, get_temp,
710 	set_temp, IDX_TEMP1_MAX);
711 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO | S_IWUSR, get_temp,
712 	set_temp, IDX_TEMP1_CRIT);
713 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO,
714 	get_temp_alarm, NULL, IDX_TEMP1_MIN);
715 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
716 	get_temp_alarm, NULL, IDX_TEMP1_MAX);
717 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
718 	get_temp_alarm, NULL, IDX_TEMP1_CRIT);
719 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO | S_IWUSR,
720 	get_temp, NULL, IDX_TEMP2_INPUT);
721 static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR, get_temp,
722 	set_temp, IDX_TEMP2_MIN);
723 static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR, get_temp,
724 	set_temp, IDX_TEMP2_MAX);
725 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO | S_IWUSR, get_temp,
726 	set_temp, IDX_TEMP2_CRIT);
727 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO,
728 	get_temp2_fault, NULL, 0);
729 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO,
730 	get_temp_alarm, NULL, IDX_TEMP2_MIN);
731 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO,
732 	get_temp_alarm, NULL, IDX_TEMP2_MAX);
733 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO,
734 	get_temp_alarm, NULL, IDX_TEMP2_CRIT);
735 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, IDX_FAN1_INPUT);
736 static SENSOR_DEVICE_ATTR(fan1_min, S_IRUGO | S_IWUSR,
737 	get_fan, set_fan, IDX_FAN1_MIN);
738 static SENSOR_DEVICE_ATTR(fan1_max, S_IRUGO | S_IWUSR,
739 	get_fan, set_fan, IDX_FAN1_MAX);
740 static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan1_fault, NULL, 0);
741 static SENSOR_DEVICE_ATTR(fan1_div, S_IRUGO | S_IWUSR,
742 	get_fan1_div, set_fan1_div, 0);
743 
744 static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm1, set_pwm1, 0);
745 static SENSOR_DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
746 	get_pwm1_enable, set_pwm1_enable, 0);
747 static SENSOR_DEVICE_ATTR(pwm1_auto_point1_pwm, S_IRUGO,
748 	get_pwm1_auto_point_pwm, NULL, 0);
749 static SENSOR_DEVICE_ATTR(pwm1_auto_point2_pwm, S_IWUSR | S_IRUGO,
750 	get_pwm1_auto_point_pwm, set_pwm1_auto_point_pwm, 1);
751 static SENSOR_DEVICE_ATTR(pwm1_auto_point3_pwm, S_IRUGO,
752 	get_pwm1_auto_point_pwm, NULL, 2);
753 static SENSOR_DEVICE_ATTR(pwm1_auto_channels_temp, S_IRUGO,
754 	get_pwm1_auto_channels_temp, NULL, 0);
755 static SENSOR_DEVICE_ATTR_2(temp1_auto_point1_temp, S_IRUGO,
756 	get_temp_auto_point_temp, NULL, 1, 0);
757 static SENSOR_DEVICE_ATTR_2(temp1_auto_point2_temp, S_IWUSR | S_IRUGO,
758 	get_temp_auto_point_temp, set_temp_auto_point_temp, 1, 1);
759 static SENSOR_DEVICE_ATTR_2(temp1_auto_point3_temp, S_IWUSR | S_IRUGO,
760 	get_temp_auto_point_temp, set_temp_auto_point_temp, 1, 2);
761 
762 static SENSOR_DEVICE_ATTR_2(temp2_auto_point1_temp, S_IWUSR | S_IRUGO,
763 	get_temp_auto_point_temp, set_temp_auto_point_temp, 2, 0);
764 static SENSOR_DEVICE_ATTR_2(temp2_auto_point2_temp, S_IWUSR | S_IRUGO,
765 	get_temp_auto_point_temp, set_temp_auto_point_temp, 2, 1);
766 static SENSOR_DEVICE_ATTR_2(temp2_auto_point3_temp, S_IWUSR | S_IRUGO,
767 	get_temp_auto_point_temp, set_temp_auto_point_temp, 2, 2);
768 
769 
770 
771 static struct attribute *amc6821_attrs[] = {
772 	&sensor_dev_attr_temp1_input.dev_attr.attr,
773 	&sensor_dev_attr_temp1_min.dev_attr.attr,
774 	&sensor_dev_attr_temp1_max.dev_attr.attr,
775 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
776 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
777 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
778 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
779 	&sensor_dev_attr_temp2_input.dev_attr.attr,
780 	&sensor_dev_attr_temp2_min.dev_attr.attr,
781 	&sensor_dev_attr_temp2_max.dev_attr.attr,
782 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
783 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
784 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
785 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
786 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
787 	&sensor_dev_attr_fan1_input.dev_attr.attr,
788 	&sensor_dev_attr_fan1_min.dev_attr.attr,
789 	&sensor_dev_attr_fan1_max.dev_attr.attr,
790 	&sensor_dev_attr_fan1_fault.dev_attr.attr,
791 	&sensor_dev_attr_fan1_div.dev_attr.attr,
792 	&sensor_dev_attr_pwm1.dev_attr.attr,
793 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
794 	&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
795 	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
796 	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
797 	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
798 	&sensor_dev_attr_temp1_auto_point1_temp.dev_attr.attr,
799 	&sensor_dev_attr_temp1_auto_point2_temp.dev_attr.attr,
800 	&sensor_dev_attr_temp1_auto_point3_temp.dev_attr.attr,
801 	&sensor_dev_attr_temp2_auto_point1_temp.dev_attr.attr,
802 	&sensor_dev_attr_temp2_auto_point2_temp.dev_attr.attr,
803 	&sensor_dev_attr_temp2_auto_point3_temp.dev_attr.attr,
804 	NULL
805 };
806 
807 static struct attribute_group amc6821_attr_grp = {
808 	.attrs = amc6821_attrs,
809 };
810 
811 
812 
813 /* Return 0 if detection is successful, -ENODEV otherwise */
814 static int amc6821_detect(
815 		struct i2c_client *client,
816 		struct i2c_board_info *info)
817 {
818 	struct i2c_adapter *adapter = client->adapter;
819 	int address = client->addr;
820 	int dev_id, comp_id;
821 
822 	dev_dbg(&adapter->dev, "amc6821_detect called.\n");
823 
824 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
825 		dev_dbg(&adapter->dev,
826 			"amc6821: I2C bus doesn't support byte mode, "
827 			"skipping.\n");
828 		return -ENODEV;
829 	}
830 
831 	dev_id = i2c_smbus_read_byte_data(client, AMC6821_REG_DEV_ID);
832 	comp_id = i2c_smbus_read_byte_data(client, AMC6821_REG_COMP_ID);
833 	if (dev_id != 0x21 || comp_id != 0x49) {
834 		dev_dbg(&adapter->dev,
835 			"amc6821: detection failed at 0x%02x.\n",
836 			address);
837 		return -ENODEV;
838 	}
839 
840 	/* Bit 7 of the address register is ignored, so we can check the
841 	   ID registers again */
842 	dev_id = i2c_smbus_read_byte_data(client, 0x80 | AMC6821_REG_DEV_ID);
843 	comp_id = i2c_smbus_read_byte_data(client, 0x80 | AMC6821_REG_COMP_ID);
844 	if (dev_id != 0x21 || comp_id != 0x49) {
845 		dev_dbg(&adapter->dev,
846 			"amc6821: detection failed at 0x%02x.\n",
847 			address);
848 		return -ENODEV;
849 	}
850 
851 	dev_info(&adapter->dev, "amc6821: chip found at 0x%02x.\n", address);
852 	strlcpy(info->type, "amc6821", I2C_NAME_SIZE);
853 
854 	return 0;
855 }
856 
857 static int amc6821_probe(
858 	struct i2c_client *client,
859 	const struct i2c_device_id *id)
860 {
861 	struct amc6821_data *data;
862 	int err;
863 
864 	data = kzalloc(sizeof(struct amc6821_data), GFP_KERNEL);
865 	if (!data) {
866 		dev_err(&client->dev, "out of memory.\n");
867 		return -ENOMEM;
868 	}
869 
870 
871 	i2c_set_clientdata(client, data);
872 	mutex_init(&data->update_lock);
873 
874 	/*
875 	 * Initialize the amc6821 chip
876 	 */
877 	err = amc6821_init_client(client);
878 	if (err)
879 		goto err_free;
880 
881 	err = sysfs_create_group(&client->dev.kobj, &amc6821_attr_grp);
882 	if (err)
883 		goto err_free;
884 
885 	data->hwmon_dev = hwmon_device_register(&client->dev);
886 	if (!IS_ERR(data->hwmon_dev))
887 		return 0;
888 
889 	err = PTR_ERR(data->hwmon_dev);
890 	dev_err(&client->dev, "error registering hwmon device.\n");
891 	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
892 err_free:
893 	kfree(data);
894 	return err;
895 }
896 
897 static int amc6821_remove(struct i2c_client *client)
898 {
899 	struct amc6821_data *data = i2c_get_clientdata(client);
900 
901 	hwmon_device_unregister(data->hwmon_dev);
902 	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
903 
904 	kfree(data);
905 
906 	return 0;
907 }
908 
909 
910 static int amc6821_init_client(struct i2c_client *client)
911 {
912 	int config;
913 	int err = -EIO;
914 
915 	if (init) {
916 		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF4);
917 
918 		if (config < 0) {
919 				dev_err(&client->dev,
920 			"Error reading configuration register, aborting.\n");
921 				return err;
922 		}
923 
924 		config |= AMC6821_CONF4_MODE;
925 
926 		if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF4,
927 				config)) {
928 			dev_err(&client->dev,
929 			"Configuration register write error, aborting.\n");
930 			return err;
931 		}
932 
933 		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF3);
934 
935 		if (config < 0) {
936 			dev_err(&client->dev,
937 			"Error reading configuration register, aborting.\n");
938 			return err;
939 		}
940 
941 		dev_info(&client->dev, "Revision %d\n", config & 0x0f);
942 
943 		config &= ~AMC6821_CONF3_THERM_FAN_EN;
944 
945 		if (i2c_smbus_write_byte_data(client, AMC6821_REG_CONF3,
946 				config)) {
947 			dev_err(&client->dev,
948 			"Configuration register write error, aborting.\n");
949 			return err;
950 		}
951 
952 		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF2);
953 
954 		if (config < 0) {
955 			dev_err(&client->dev,
956 			"Error reading configuration register, aborting.\n");
957 			return err;
958 		}
959 
960 		config &= ~AMC6821_CONF2_RTFIE;
961 		config &= ~AMC6821_CONF2_LTOIE;
962 		config &= ~AMC6821_CONF2_RTOIE;
963 		if (i2c_smbus_write_byte_data(client,
964 				AMC6821_REG_CONF2, config)) {
965 			dev_err(&client->dev,
966 			"Configuration register write error, aborting.\n");
967 			return err;
968 		}
969 
970 		config = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
971 
972 		if (config < 0) {
973 			dev_err(&client->dev,
974 			"Error reading configuration register, aborting.\n");
975 			return err;
976 		}
977 
978 		config &= ~AMC6821_CONF1_THERMOVIE;
979 		config &= ~AMC6821_CONF1_FANIE;
980 		config |= AMC6821_CONF1_START;
981 		if (pwminv)
982 			config |= AMC6821_CONF1_PWMINV;
983 		else
984 			config &= ~AMC6821_CONF1_PWMINV;
985 
986 		if (i2c_smbus_write_byte_data(
987 				client, AMC6821_REG_CONF1, config)) {
988 			dev_err(&client->dev,
989 			"Configuration register write error, aborting.\n");
990 			return err;
991 		}
992 	}
993 	return 0;
994 }
995 
996 
997 static struct amc6821_data *amc6821_update_device(struct device *dev)
998 {
999 	struct i2c_client *client = to_i2c_client(dev);
1000 	struct amc6821_data *data = i2c_get_clientdata(client);
1001 	int timeout = HZ;
1002 	u8 reg;
1003 	int i;
1004 
1005 	mutex_lock(&data->update_lock);
1006 
1007 	if (time_after(jiffies, data->last_updated + timeout) ||
1008 			!data->valid) {
1009 
1010 		for (i = 0; i < TEMP_IDX_LEN; i++)
1011 			data->temp[i] = i2c_smbus_read_byte_data(client,
1012 				temp_reg[i]);
1013 
1014 		data->stat1 = i2c_smbus_read_byte_data(client,
1015 			AMC6821_REG_STAT1);
1016 		data->stat2 = i2c_smbus_read_byte_data(client,
1017 			AMC6821_REG_STAT2);
1018 
1019 		data->pwm1 = i2c_smbus_read_byte_data(client,
1020 			AMC6821_REG_DCY);
1021 		for (i = 0; i < FAN1_IDX_LEN; i++) {
1022 			data->fan[i] = i2c_smbus_read_byte_data(
1023 					client,
1024 					fan_reg_low[i]);
1025 			data->fan[i] += i2c_smbus_read_byte_data(
1026 					client,
1027 					fan_reg_hi[i]) << 8;
1028 		}
1029 		data->fan1_div = i2c_smbus_read_byte_data(client,
1030 			AMC6821_REG_CONF4);
1031 		data->fan1_div = data->fan1_div & AMC6821_CONF4_PSPR ? 4 : 2;
1032 
1033 		data->pwm1_auto_point_pwm[0] = 0;
1034 		data->pwm1_auto_point_pwm[2] = 255;
1035 		data->pwm1_auto_point_pwm[1] = i2c_smbus_read_byte_data(client,
1036 			AMC6821_REG_DCY_LOW_TEMP);
1037 
1038 		data->temp1_auto_point_temp[0] =
1039 			i2c_smbus_read_byte_data(client,
1040 					AMC6821_REG_PSV_TEMP);
1041 		data->temp2_auto_point_temp[0] =
1042 				data->temp1_auto_point_temp[0];
1043 		reg = i2c_smbus_read_byte_data(client,
1044 			AMC6821_REG_LTEMP_FAN_CTRL);
1045 		data->temp1_auto_point_temp[1] = (reg & 0xF8) >> 1;
1046 		reg &= 0x07;
1047 		reg = 0x20 >> reg;
1048 		if (reg > 0)
1049 			data->temp1_auto_point_temp[2] =
1050 				data->temp1_auto_point_temp[1] +
1051 				(data->pwm1_auto_point_pwm[2] -
1052 				data->pwm1_auto_point_pwm[1]) / reg;
1053 		else
1054 			data->temp1_auto_point_temp[2] = 255;
1055 
1056 		reg = i2c_smbus_read_byte_data(client,
1057 			AMC6821_REG_RTEMP_FAN_CTRL);
1058 		data->temp2_auto_point_temp[1] = (reg & 0xF8) >> 1;
1059 		reg &= 0x07;
1060 		reg = 0x20 >> reg;
1061 		if (reg > 0)
1062 			data->temp2_auto_point_temp[2] =
1063 				data->temp2_auto_point_temp[1] +
1064 				(data->pwm1_auto_point_pwm[2] -
1065 				data->pwm1_auto_point_pwm[1]) / reg;
1066 		else
1067 			data->temp2_auto_point_temp[2] = 255;
1068 
1069 		reg = i2c_smbus_read_byte_data(client, AMC6821_REG_CONF1);
1070 		reg = (reg >> 5) & 0x3;
1071 		switch (reg) {
1072 		case 0: /*open loop: software sets pwm1*/
1073 			data->pwm1_auto_channels_temp = 0;
1074 			data->pwm1_enable = 1;
1075 			break;
1076 		case 2: /*closed loop: remote T (temp2)*/
1077 			data->pwm1_auto_channels_temp = 2;
1078 			data->pwm1_enable = 2;
1079 			break;
1080 		case 3: /*closed loop: local and remote T (temp2)*/
1081 			data->pwm1_auto_channels_temp = 3;
1082 			data->pwm1_enable = 3;
1083 			break;
1084 		case 1: /*semi-open loop: software sets rpm, chip controls pwm1,
1085 			  *currently not implemented
1086 			  */
1087 			data->pwm1_auto_channels_temp = 0;
1088 			data->pwm1_enable = 0;
1089 			break;
1090 		}
1091 
1092 		data->last_updated = jiffies;
1093 		data->valid = 1;
1094 	}
1095 	mutex_unlock(&data->update_lock);
1096 	return data;
1097 }
1098 
1099 
1100 static int __init amc6821_init(void)
1101 {
1102 	return i2c_add_driver(&amc6821_driver);
1103 }
1104 
1105 static void __exit amc6821_exit(void)
1106 {
1107 	i2c_del_driver(&amc6821_driver);
1108 }
1109 
1110 module_init(amc6821_init);
1111 module_exit(amc6821_exit);
1112 
1113 
1114 MODULE_LICENSE("GPL");
1115 MODULE_AUTHOR("T. Mertelj <tomaz.mertelj@guest.arnes.si>");
1116 MODULE_DESCRIPTION("Texas Instruments amc6821 hwmon driver");
1117