xref: /openbmc/linux/drivers/hwmon/adm9240.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * adm9240.c	Part of lm_sensors, Linux kernel modules for hardware
4  *		monitoring
5  *
6  * Copyright (C) 1999	Frodo Looijaard <frodol@dds.nl>
7  *			Philip Edelbrock <phil@netroedge.com>
8  * Copyright (C) 2003	Michiel Rook <michiel@grendelproject.nl>
9  * Copyright (C) 2005	Grant Coady <gcoady.lk@gmail.com> with valuable
10  *				guidance from Jean Delvare
11  *
12  * Driver supports	Analog Devices		ADM9240
13  *			Dallas Semiconductor	DS1780
14  *			National Semiconductor	LM81
15  *
16  * ADM9240 is the reference, DS1780 and LM81 are register compatibles
17  *
18  * Voltage	Six inputs are scaled by chip, VID also reported
19  * Temperature	Chip temperature to 0.5'C, maximum and max_hysteris
20  * Fans		2 fans, low speed alarm, automatic fan clock divider
21  * Alarms	16-bit map of active alarms
22  * Analog Out	0..1250 mV output
23  *
24  * Chassis Intrusion: clear CI latch with 'echo 0 > intrusion0_alarm'
25  *
26  * Test hardware: Intel SE440BX-2 desktop motherboard --Grant
27  *
28  * LM81 extended temp reading not implemented
29  */
30 
31 #include <linux/bits.h>
32 #include <linux/init.h>
33 #include <linux/module.h>
34 #include <linux/slab.h>
35 #include <linux/i2c.h>
36 #include <linux/hwmon-sysfs.h>
37 #include <linux/hwmon.h>
38 #include <linux/hwmon-vid.h>
39 #include <linux/err.h>
40 #include <linux/mutex.h>
41 #include <linux/regmap.h>
42 
43 /* Addresses to scan */
44 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
45 					I2C_CLIENT_END };
46 
47 enum chips { adm9240, ds1780, lm81 };
48 
49 /* ADM9240 registers */
50 #define ADM9240_REG_MAN_ID		0x3e
51 #define ADM9240_REG_DIE_REV		0x3f
52 #define ADM9240_REG_CONFIG		0x40
53 
54 #define ADM9240_REG_IN(nr)		(0x20 + (nr))   /* 0..5 */
55 #define ADM9240_REG_IN_MAX(nr)		(0x2b + (nr) * 2)
56 #define ADM9240_REG_IN_MIN(nr)		(0x2c + (nr) * 2)
57 #define ADM9240_REG_FAN(nr)		(0x28 + (nr))   /* 0..1 */
58 #define ADM9240_REG_FAN_MIN(nr)		(0x3b + (nr))
59 #define ADM9240_REG_INT(nr)		(0x41 + (nr))
60 #define ADM9240_REG_INT_MASK(nr)	(0x43 + (nr))
61 #define ADM9240_REG_TEMP		0x27
62 #define ADM9240_REG_TEMP_MAX(nr)	(0x39 + (nr)) /* 0, 1 = high, hyst */
63 #define ADM9240_REG_ANALOG_OUT		0x19
64 #define ADM9240_REG_CHASSIS_CLEAR	0x46
65 #define ADM9240_REG_VID_FAN_DIV		0x47
66 #define ADM9240_REG_I2C_ADDR		0x48
67 #define ADM9240_REG_VID4		0x49
68 #define ADM9240_REG_TEMP_CONF		0x4b
69 
70 /* generalised scaling with integer rounding */
71 static inline int SCALE(long val, int mul, int div)
72 {
73 	if (val < 0)
74 		return (val * mul - div / 2) / div;
75 	else
76 		return (val * mul + div / 2) / div;
77 }
78 
79 /* adm9240 internally scales voltage measurements */
80 static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };
81 
82 static inline unsigned int IN_FROM_REG(u8 reg, int n)
83 {
84 	return SCALE(reg, nom_mv[n], 192);
85 }
86 
87 static inline u8 IN_TO_REG(unsigned long val, int n)
88 {
89 	val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
90 	return SCALE(val, 192, nom_mv[n]);
91 }
92 
93 /* temperature range: -40..125, 127 disables temperature alarm */
94 static inline s8 TEMP_TO_REG(long val)
95 {
96 	val = clamp_val(val, -40000, 127000);
97 	return SCALE(val, 1, 1000);
98 }
99 
100 /* two fans, each with low fan speed limit */
101 static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
102 {
103 	if (!reg) /* error */
104 		return -1;
105 
106 	if (reg == 255)
107 		return 0;
108 
109 	return SCALE(1350000, 1, reg * div);
110 }
111 
112 /* analog out 0..1250mV */
113 static inline u8 AOUT_TO_REG(unsigned long val)
114 {
115 	val = clamp_val(val, 0, 1250);
116 	return SCALE(val, 255, 1250);
117 }
118 
119 static inline unsigned int AOUT_FROM_REG(u8 reg)
120 {
121 	return SCALE(reg, 1250, 255);
122 }
123 
124 /* per client data */
125 struct adm9240_data {
126 	struct device *dev;
127 	struct regmap *regmap;
128 	struct mutex update_lock;
129 
130 	u8 fan_div[2];		/* rw	fan1_div, read-only accessor */
131 	u8 vrm;			/* --	vrm set on startup, no accessor */
132 };
133 
134 /* write new fan div, callers must hold data->update_lock */
135 static int adm9240_write_fan_div(struct adm9240_data *data, int channel, u8 fan_div)
136 {
137 	unsigned int reg, old, shift = (channel + 2) * 2;
138 	int err;
139 
140 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &reg);
141 	if (err < 0)
142 		return err;
143 	old = (reg >> shift) & 3;
144 	reg &= ~(3 << shift);
145 	reg |= (fan_div << shift);
146 	err = regmap_write(data->regmap, ADM9240_REG_VID_FAN_DIV, reg);
147 	if (err < 0)
148 		return err;
149 	dev_dbg(data->dev,
150 		"fan%d clock divider changed from %lu to %lu\n",
151 		channel + 1, BIT(old), BIT(fan_div));
152 
153 	return 0;
154 }
155 
156 /*
157  * set fan speed low limit:
158  *
159  * - value is zero: disable fan speed low limit alarm
160  *
161  * - value is below fan speed measurement range: enable fan speed low
162  *   limit alarm to be asserted while fan speed too slow to measure
163  *
164  * - otherwise: select fan clock divider to suit fan speed low limit,
165  *   measurement code may adjust registers to ensure fan speed reading
166  */
167 static int adm9240_fan_min_write(struct adm9240_data *data, int channel, long val)
168 {
169 	u8 new_div;
170 	u8 fan_min;
171 	int err;
172 
173 	mutex_lock(&data->update_lock);
174 
175 	if (!val) {
176 		fan_min = 255;
177 		new_div = data->fan_div[channel];
178 
179 		dev_dbg(data->dev, "fan%u low limit set disabled\n", channel + 1);
180 	} else if (val < 1350000 / (8 * 254)) {
181 		new_div = 3;
182 		fan_min = 254;
183 
184 		dev_dbg(data->dev, "fan%u low limit set minimum %u\n",
185 			channel + 1, FAN_FROM_REG(254, BIT(new_div)));
186 	} else {
187 		unsigned int new_min = 1350000 / val;
188 
189 		new_div = 0;
190 		while (new_min > 192 && new_div < 3) {
191 			new_div++;
192 			new_min /= 2;
193 		}
194 		if (!new_min) /* keep > 0 */
195 			new_min++;
196 
197 		fan_min = new_min;
198 
199 		dev_dbg(data->dev, "fan%u low limit set fan speed %u\n",
200 			channel + 1, FAN_FROM_REG(new_min, BIT(new_div)));
201 	}
202 
203 	if (new_div != data->fan_div[channel]) {
204 		data->fan_div[channel] = new_div;
205 		adm9240_write_fan_div(data, channel, new_div);
206 	}
207 	err = regmap_write(data->regmap, ADM9240_REG_FAN_MIN(channel), fan_min);
208 
209 	mutex_unlock(&data->update_lock);
210 
211 	return err;
212 }
213 
214 static ssize_t cpu0_vid_show(struct device *dev,
215 			     struct device_attribute *attr, char *buf)
216 {
217 	struct adm9240_data *data = dev_get_drvdata(dev);
218 	unsigned int regval;
219 	int err;
220 	u8 vid;
221 
222 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
223 	if (err < 0)
224 		return err;
225 	vid = regval & 0x0f;
226 	err = regmap_read(data->regmap, ADM9240_REG_VID4, &regval);
227 	if (err < 0)
228 		return err;
229 	vid |= (regval & 1) << 4;
230 	return sprintf(buf, "%d\n", vid_from_reg(vid, data->vrm));
231 }
232 static DEVICE_ATTR_RO(cpu0_vid);
233 
234 static ssize_t aout_output_show(struct device *dev,
235 				struct device_attribute *attr, char *buf)
236 {
237 	struct adm9240_data *data = dev_get_drvdata(dev);
238 	unsigned int regval;
239 	int err;
240 
241 	err = regmap_read(data->regmap, ADM9240_REG_ANALOG_OUT, &regval);
242 	if (err)
243 		return err;
244 
245 	return sprintf(buf, "%d\n", AOUT_FROM_REG(regval));
246 }
247 
248 static ssize_t aout_output_store(struct device *dev,
249 				 struct device_attribute *attr,
250 				 const char *buf, size_t count)
251 {
252 	struct adm9240_data *data = dev_get_drvdata(dev);
253 	long val;
254 	int err;
255 
256 	err = kstrtol(buf, 10, &val);
257 	if (err)
258 		return err;
259 
260 	err = regmap_write(data->regmap, ADM9240_REG_ANALOG_OUT, AOUT_TO_REG(val));
261 	return err < 0 ? err : count;
262 }
263 static DEVICE_ATTR_RW(aout_output);
264 
265 static struct attribute *adm9240_attrs[] = {
266 	&dev_attr_aout_output.attr,
267 	&dev_attr_cpu0_vid.attr,
268 	NULL
269 };
270 
271 ATTRIBUTE_GROUPS(adm9240);
272 
273 /*** sensor chip detect and driver install ***/
274 
275 /* Return 0 if detection is successful, -ENODEV otherwise */
276 static int adm9240_detect(struct i2c_client *new_client,
277 			  struct i2c_board_info *info)
278 {
279 	struct i2c_adapter *adapter = new_client->adapter;
280 	const char *name = "";
281 	int address = new_client->addr;
282 	u8 man_id, die_rev;
283 
284 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
285 		return -ENODEV;
286 
287 	/* verify chip: reg address should match i2c address */
288 	if (i2c_smbus_read_byte_data(new_client, ADM9240_REG_I2C_ADDR) != address)
289 		return -ENODEV;
290 
291 	/* check known chip manufacturer */
292 	man_id = i2c_smbus_read_byte_data(new_client, ADM9240_REG_MAN_ID);
293 	if (man_id == 0x23)
294 		name = "adm9240";
295 	else if (man_id == 0xda)
296 		name = "ds1780";
297 	else if (man_id == 0x01)
298 		name = "lm81";
299 	else
300 		return -ENODEV;
301 
302 	/* successful detect, print chip info */
303 	die_rev = i2c_smbus_read_byte_data(new_client, ADM9240_REG_DIE_REV);
304 	dev_info(&adapter->dev, "found %s revision %u\n",
305 		 man_id == 0x23 ? "ADM9240" :
306 		 man_id == 0xda ? "DS1780" : "LM81", die_rev);
307 
308 	strscpy(info->type, name, I2C_NAME_SIZE);
309 
310 	return 0;
311 }
312 
313 static int adm9240_init_client(struct adm9240_data *data)
314 {
315 	unsigned int regval;
316 	u8 conf, mode;
317 	int err;
318 
319 	err = regmap_raw_read(data->regmap, ADM9240_REG_CONFIG, &conf, 1);
320 	if (err < 0)
321 		return err;
322 	err = regmap_raw_read(data->regmap, ADM9240_REG_TEMP_CONF, &mode, 1);
323 	if (err < 0)
324 		return err;
325 	mode &= 3;
326 
327 	data->vrm = vid_which_vrm(); /* need this to report vid as mV */
328 
329 	dev_info(data->dev, "Using VRM: %d.%d\n", data->vrm / 10,
330 		 data->vrm % 10);
331 
332 	if (conf & 1) { /* measurement cycle running: report state */
333 
334 		dev_info(data->dev, "status: config 0x%02x mode %u\n",
335 			 conf, mode);
336 
337 	} else { /* cold start: open limits before starting chip */
338 		int i;
339 
340 		for (i = 0; i < 6; i++) {
341 			err = regmap_write(data->regmap,
342 					   ADM9240_REG_IN_MIN(i), 0);
343 			if (err < 0)
344 				return err;
345 			err = regmap_write(data->regmap,
346 					   ADM9240_REG_IN_MAX(i), 255);
347 			if (err < 0)
348 				return err;
349 		}
350 		for (i = 0; i < 2; i++) {
351 			err = regmap_write(data->regmap,
352 					   ADM9240_REG_FAN_MIN(i), 255);
353 			if (err < 0)
354 				return err;
355 		}
356 		for (i = 0; i < 2; i++) {
357 			err = regmap_write(data->regmap,
358 					   ADM9240_REG_TEMP_MAX(i), 127);
359 			if (err < 0)
360 				return err;
361 		}
362 
363 		/* start measurement cycle */
364 		err = regmap_write(data->regmap, ADM9240_REG_CONFIG, 1);
365 		if (err < 0)
366 			return err;
367 
368 		dev_info(data->dev,
369 			 "cold start: config was 0x%02x mode %u\n", conf, mode);
370 	}
371 
372 	/* read fan divs */
373 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
374 	if (err < 0)
375 		return err;
376 	data->fan_div[0] = (regval >> 4) & 3;
377 	data->fan_div[1] = (regval >> 6) & 3;
378 	return 0;
379 }
380 
381 static int adm9240_chip_read(struct device *dev, u32 attr, long *val)
382 {
383 	struct adm9240_data *data = dev_get_drvdata(dev);
384 	u8 regs[2];
385 	int err;
386 
387 	switch (attr) {
388 	case hwmon_chip_alarms:
389 		err = regmap_bulk_read(data->regmap, ADM9240_REG_INT(0), &regs, 2);
390 		if (err < 0)
391 			return err;
392 		*val = regs[0] | regs[1] << 8;
393 		break;
394 	default:
395 		return -EOPNOTSUPP;
396 	}
397 	return 0;
398 }
399 
400 static int adm9240_intrusion_read(struct device *dev, u32 attr, long *val)
401 {
402 	struct adm9240_data *data = dev_get_drvdata(dev);
403 	unsigned int regval;
404 	int err;
405 
406 	switch (attr) {
407 	case hwmon_intrusion_alarm:
408 		err = regmap_read(data->regmap, ADM9240_REG_INT(1), &regval);
409 		if (err < 0)
410 			return err;
411 		*val = !!(regval & BIT(4));
412 		break;
413 	default:
414 		return -EOPNOTSUPP;
415 	}
416 	return 0;
417 }
418 
419 static int adm9240_intrusion_write(struct device *dev, u32 attr, long val)
420 {
421 	struct adm9240_data *data = dev_get_drvdata(dev);
422 	int err;
423 
424 	switch (attr) {
425 	case hwmon_intrusion_alarm:
426 		if (val)
427 			return -EINVAL;
428 		err = regmap_write(data->regmap, ADM9240_REG_CHASSIS_CLEAR, 0x80);
429 		if (err < 0)
430 			return err;
431 		dev_dbg(data->dev, "chassis intrusion latch cleared\n");
432 		break;
433 	default:
434 		return -EOPNOTSUPP;
435 	}
436 	return 0;
437 }
438 
439 static int adm9240_in_read(struct device *dev, u32 attr, int channel, long *val)
440 {
441 	struct adm9240_data *data = dev_get_drvdata(dev);
442 	unsigned int regval;
443 	int reg;
444 	int err;
445 
446 	switch (attr) {
447 	case hwmon_in_input:
448 		reg = ADM9240_REG_IN(channel);
449 		break;
450 	case hwmon_in_min:
451 		reg = ADM9240_REG_IN_MIN(channel);
452 		break;
453 	case hwmon_in_max:
454 		reg = ADM9240_REG_IN_MAX(channel);
455 		break;
456 	case hwmon_in_alarm:
457 		if (channel < 4) {
458 			reg = ADM9240_REG_INT(0);
459 		} else {
460 			reg = ADM9240_REG_INT(1);
461 			channel -= 4;
462 		}
463 		err = regmap_read(data->regmap, reg, &regval);
464 		if (err < 0)
465 			return err;
466 		*val = !!(regval & BIT(channel));
467 		return 0;
468 	default:
469 		return -EOPNOTSUPP;
470 	}
471 	err = regmap_read(data->regmap, reg, &regval);
472 	if (err < 0)
473 		return err;
474 	*val = IN_FROM_REG(regval, channel);
475 	return 0;
476 }
477 
478 static int adm9240_in_write(struct device *dev, u32 attr, int channel, long val)
479 {
480 	struct adm9240_data *data = dev_get_drvdata(dev);
481 	int reg;
482 
483 	switch (attr) {
484 	case hwmon_in_min:
485 		reg = ADM9240_REG_IN_MIN(channel);
486 		break;
487 	case hwmon_in_max:
488 		reg = ADM9240_REG_IN_MAX(channel);
489 		break;
490 	default:
491 		return -EOPNOTSUPP;
492 	}
493 	return regmap_write(data->regmap, reg, IN_TO_REG(val, channel));
494 }
495 
496 static int adm9240_fan_read(struct device *dev, u32 attr, int channel, long *val)
497 {
498 	struct adm9240_data *data = dev_get_drvdata(dev);
499 	unsigned int regval;
500 	int err;
501 
502 	switch (attr) {
503 	case hwmon_fan_input:
504 		err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), &regval);
505 		if (err < 0)
506 			return err;
507 		if (regval == 255 && data->fan_div[channel] < 3) {
508 			/* adjust fan clock divider on overflow */
509 			err = adm9240_write_fan_div(data, channel,
510 						    ++data->fan_div[channel]);
511 			if (err)
512 				return err;
513 		}
514 		*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
515 		break;
516 	case hwmon_fan_div:
517 		*val = BIT(data->fan_div[channel]);
518 		break;
519 	case hwmon_fan_min:
520 		err = regmap_read(data->regmap, ADM9240_REG_FAN_MIN(channel), &regval);
521 		if (err < 0)
522 			return err;
523 		*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
524 		break;
525 	case hwmon_fan_alarm:
526 		err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
527 		if (err < 0)
528 			return err;
529 		*val = !!(regval & BIT(channel + 6));
530 		break;
531 	default:
532 		return -EOPNOTSUPP;
533 	}
534 	return 0;
535 }
536 
537 static int adm9240_fan_write(struct device *dev, u32 attr, int channel, long val)
538 {
539 	struct adm9240_data *data = dev_get_drvdata(dev);
540 	int err;
541 
542 	switch (attr) {
543 	case hwmon_fan_min:
544 		err = adm9240_fan_min_write(data, channel, val);
545 		if (err < 0)
546 			return err;
547 		break;
548 	default:
549 		return -EOPNOTSUPP;
550 	}
551 	return 0;
552 }
553 
554 static int adm9240_temp_read(struct device *dev, u32 attr, int channel, long *val)
555 {
556 	struct adm9240_data *data = dev_get_drvdata(dev);
557 	unsigned int regval;
558 	int err, temp;
559 
560 	switch (attr) {
561 	case hwmon_temp_input:
562 		err = regmap_read(data->regmap, ADM9240_REG_TEMP, &regval);
563 		if (err < 0)
564 			return err;
565 		temp = regval << 1;
566 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_CONF, &regval);
567 		if (err < 0)
568 			return err;
569 		temp |= regval >> 7;
570 		*val = sign_extend32(temp, 8) * 500;
571 		break;
572 	case hwmon_temp_max:
573 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(0), &regval);
574 		if (err < 0)
575 			return err;
576 		*val = (s8)regval * 1000;
577 		break;
578 	case hwmon_temp_max_hyst:
579 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(1), &regval);
580 		if (err < 0)
581 			return err;
582 		*val = (s8)regval * 1000;
583 		break;
584 	case hwmon_temp_alarm:
585 		err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
586 		if (err < 0)
587 			return err;
588 		*val = !!(regval & BIT(4));
589 		break;
590 	default:
591 		return -EOPNOTSUPP;
592 	}
593 	return 0;
594 }
595 
596 static int adm9240_temp_write(struct device *dev, u32 attr, int channel, long val)
597 {
598 	struct adm9240_data *data = dev_get_drvdata(dev);
599 	int reg;
600 
601 	switch (attr) {
602 	case hwmon_temp_max:
603 		reg = ADM9240_REG_TEMP_MAX(0);
604 		break;
605 	case hwmon_temp_max_hyst:
606 		reg = ADM9240_REG_TEMP_MAX(1);
607 		break;
608 	default:
609 		return -EOPNOTSUPP;
610 	}
611 	return regmap_write(data->regmap, reg, TEMP_TO_REG(val));
612 }
613 
614 static int adm9240_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
615 			int channel, long *val)
616 {
617 	switch (type) {
618 	case hwmon_chip:
619 		return adm9240_chip_read(dev, attr, val);
620 	case hwmon_intrusion:
621 		return adm9240_intrusion_read(dev, attr, val);
622 	case hwmon_in:
623 		return adm9240_in_read(dev, attr, channel, val);
624 	case hwmon_fan:
625 		return adm9240_fan_read(dev, attr, channel, val);
626 	case hwmon_temp:
627 		return adm9240_temp_read(dev, attr, channel, val);
628 	default:
629 		return -EOPNOTSUPP;
630 	}
631 }
632 
633 static int adm9240_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
634 			 int channel, long val)
635 {
636 	switch (type) {
637 	case hwmon_intrusion:
638 		return adm9240_intrusion_write(dev, attr, val);
639 	case hwmon_in:
640 		return adm9240_in_write(dev, attr, channel, val);
641 	case hwmon_fan:
642 		return adm9240_fan_write(dev, attr, channel, val);
643 	case hwmon_temp:
644 		return adm9240_temp_write(dev, attr, channel, val);
645 	default:
646 		return -EOPNOTSUPP;
647 	}
648 }
649 
650 static umode_t adm9240_is_visible(const void *_data, enum hwmon_sensor_types type,
651 				  u32 attr, int channel)
652 {
653 	umode_t mode = 0;
654 
655 	switch (type) {
656 	case hwmon_chip:
657 		switch (attr) {
658 		case hwmon_chip_alarms:
659 			mode = 0444;
660 			break;
661 		default:
662 			break;
663 		}
664 		break;
665 	case hwmon_intrusion:
666 		switch (attr) {
667 		case hwmon_intrusion_alarm:
668 			mode = 0644;
669 			break;
670 		default:
671 			break;
672 		}
673 		break;
674 	case hwmon_temp:
675 		switch (attr) {
676 		case hwmon_temp:
677 		case hwmon_temp_alarm:
678 			mode = 0444;
679 			break;
680 		case hwmon_temp_max:
681 		case hwmon_temp_max_hyst:
682 			mode = 0644;
683 			break;
684 		default:
685 			break;
686 		}
687 		break;
688 	case hwmon_fan:
689 		switch (attr) {
690 		case hwmon_fan_input:
691 		case hwmon_fan_div:
692 		case hwmon_fan_alarm:
693 			mode = 0444;
694 			break;
695 		case hwmon_fan_min:
696 			mode = 0644;
697 			break;
698 		default:
699 			break;
700 		}
701 		break;
702 	case hwmon_in:
703 		switch (attr) {
704 		case hwmon_in_input:
705 		case hwmon_in_alarm:
706 			mode = 0444;
707 			break;
708 		case hwmon_in_min:
709 		case hwmon_in_max:
710 			mode = 0644;
711 			break;
712 		default:
713 			break;
714 		}
715 		break;
716 	default:
717 		break;
718 	}
719 	return mode;
720 }
721 
722 static const struct hwmon_ops adm9240_hwmon_ops = {
723 	.is_visible = adm9240_is_visible,
724 	.read = adm9240_read,
725 	.write = adm9240_write,
726 };
727 
728 static const struct hwmon_channel_info *adm9240_info[] = {
729 	HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS),
730 	HWMON_CHANNEL_INFO(intrusion, HWMON_INTRUSION_ALARM),
731 	HWMON_CHANNEL_INFO(temp,
732 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_ALARM),
733 	HWMON_CHANNEL_INFO(in,
734 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
735 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
736 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
737 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
738 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
739 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM),
740 	HWMON_CHANNEL_INFO(fan,
741 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM,
742 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM),
743 	NULL
744 };
745 
746 static const struct hwmon_chip_info adm9240_chip_info = {
747 	.ops = &adm9240_hwmon_ops,
748 	.info = adm9240_info,
749 };
750 
751 static bool adm9240_volatile_reg(struct device *dev, unsigned int reg)
752 {
753 	switch (reg) {
754 	case ADM9240_REG_IN(0) ... ADM9240_REG_IN(5):
755 	case ADM9240_REG_FAN(0) ... ADM9240_REG_FAN(1):
756 	case ADM9240_REG_INT(0) ... ADM9240_REG_INT(1):
757 	case ADM9240_REG_TEMP:
758 	case ADM9240_REG_TEMP_CONF:
759 	case ADM9240_REG_VID_FAN_DIV:
760 	case ADM9240_REG_VID4:
761 	case ADM9240_REG_ANALOG_OUT:
762 		return true;
763 	default:
764 		return false;
765 	}
766 }
767 
768 static const struct regmap_config adm9240_regmap_config = {
769 	.reg_bits = 8,
770 	.val_bits = 8,
771 	.use_single_read = true,
772 	.use_single_write = true,
773 	.volatile_reg = adm9240_volatile_reg,
774 };
775 
776 static int adm9240_probe(struct i2c_client *client)
777 {
778 	struct device *dev = &client->dev;
779 	struct device *hwmon_dev;
780 	struct adm9240_data *data;
781 	int err;
782 
783 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
784 	if (!data)
785 		return -ENOMEM;
786 
787 	data->dev = dev;
788 	mutex_init(&data->update_lock);
789 	data->regmap = devm_regmap_init_i2c(client, &adm9240_regmap_config);
790 	if (IS_ERR(data->regmap))
791 		return PTR_ERR(data->regmap);
792 
793 	err = adm9240_init_client(data);
794 	if (err < 0)
795 		return err;
796 
797 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
798 							 &adm9240_chip_info,
799 							 adm9240_groups);
800 	return PTR_ERR_OR_ZERO(hwmon_dev);
801 }
802 
803 static const struct i2c_device_id adm9240_id[] = {
804 	{ "adm9240", adm9240 },
805 	{ "ds1780", ds1780 },
806 	{ "lm81", lm81 },
807 	{ }
808 };
809 MODULE_DEVICE_TABLE(i2c, adm9240_id);
810 
811 static struct i2c_driver adm9240_driver = {
812 	.class		= I2C_CLASS_HWMON,
813 	.driver = {
814 		.name	= "adm9240",
815 	},
816 	.probe_new	= adm9240_probe,
817 	.id_table	= adm9240_id,
818 	.detect		= adm9240_detect,
819 	.address_list	= normal_i2c,
820 };
821 
822 module_i2c_driver(adm9240_driver);
823 
824 MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
825 		"Grant Coady <gcoady.lk@gmail.com> and others");
826 MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
827 MODULE_LICENSE("GPL");
828