xref: /linux/drivers/hwmon/ltc2947-core.c (revision 320fefa9e2edc67011e235ea1d50f0d00ddfe004)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Analog Devices LTC2947 high precision power and energy monitor
4  *
5  * Copyright 2019 Analog Devices Inc.
6  */
7 #include <linux/bitfield.h>
8 #include <linux/bits.h>
9 #include <linux/clk.h>
10 #include <linux/device.h>
11 #include <linux/hwmon.h>
12 #include <linux/hwmon-sysfs.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/regmap.h>
16 
17 #include "ltc2947.h"
18 
19 /* register's */
20 #define LTC2947_REG_PAGE_CTRL		0xFF
21 #define LTC2947_REG_CTRL		0xF0
22 #define LTC2947_REG_TBCTL		0xE9
23 #define LTC2947_CONT_MODE_MASK		BIT(3)
24 #define LTC2947_CONT_MODE(x)		FIELD_PREP(LTC2947_CONT_MODE_MASK, x)
25 #define LTC2947_PRE_MASK		GENMASK(2, 0)
26 #define LTC2947_PRE(x)			FIELD_PREP(LTC2947_PRE_MASK, x)
27 #define LTC2947_DIV_MASK		GENMASK(7, 3)
28 #define LTC2947_DIV(x)			FIELD_PREP(LTC2947_DIV_MASK, x)
29 #define LTC2947_SHUTDOWN_MASK		BIT(0)
30 #define LTC2947_REG_ACCUM_POL		0xE1
31 #define LTC2947_ACCUM_POL_1_MASK	GENMASK(1, 0)
32 #define LTC2947_ACCUM_POL_1(x)		FIELD_PREP(LTC2947_ACCUM_POL_1_MASK, x)
33 #define LTC2947_ACCUM_POL_2_MASK	GENMASK(3, 2)
34 #define LTC2947_ACCUM_POL_2(x)		FIELD_PREP(LTC2947_ACCUM_POL_2_MASK, x)
35 #define LTC2947_REG_ACCUM_DEADBAND	0xE4
36 #define LTC2947_REG_GPIOSTATCTL		0x67
37 #define LTC2947_GPIO_EN_MASK		BIT(0)
38 #define LTC2947_GPIO_EN(x)		FIELD_PREP(LTC2947_GPIO_EN_MASK, x)
39 #define LTC2947_GPIO_FAN_EN_MASK	BIT(6)
40 #define LTC2947_GPIO_FAN_EN(x)		FIELD_PREP(LTC2947_GPIO_FAN_EN_MASK, x)
41 #define LTC2947_GPIO_FAN_POL_MASK	BIT(7)
42 #define LTC2947_GPIO_FAN_POL(x)		FIELD_PREP(LTC2947_GPIO_FAN_POL_MASK, x)
43 #define LTC2947_REG_GPIO_ACCUM		0xE3
44 /* 200Khz */
45 #define LTC2947_CLK_MIN			200000
46 /* 25Mhz */
47 #define LTC2947_CLK_MAX			25000000
48 #define LTC2947_PAGE0			0
49 #define LTC2947_PAGE1			1
50 /* Voltage registers */
51 #define LTC2947_REG_VOLTAGE		0xA0
52 #define LTC2947_REG_VOLTAGE_MAX		0x50
53 #define LTC2947_REG_VOLTAGE_MIN		0x52
54 #define LTC2947_REG_VOLTAGE_THRE_H	0x90
55 #define LTC2947_REG_VOLTAGE_THRE_L	0x92
56 #define LTC2947_REG_DVCC		0xA4
57 #define LTC2947_REG_DVCC_MAX		0x58
58 #define LTC2947_REG_DVCC_MIN		0x5A
59 #define LTC2947_REG_DVCC_THRE_H		0x98
60 #define LTC2947_REG_DVCC_THRE_L		0x9A
61 #define LTC2947_VOLTAGE_GEN_CHAN	0
62 #define LTC2947_VOLTAGE_DVCC_CHAN	1
63 /* in mV */
64 #define VOLTAGE_MAX			15500
65 #define VOLTAGE_MIN			-300
66 #define VDVCC_MAX			15000
67 #define VDVCC_MIN			4750
68 /* Current registers */
69 #define LTC2947_REG_CURRENT		0x90
70 #define LTC2947_REG_CURRENT_MAX		0x40
71 #define LTC2947_REG_CURRENT_MIN		0x42
72 #define LTC2947_REG_CURRENT_THRE_H	0x80
73 #define LTC2947_REG_CURRENT_THRE_L	0x82
74 /* in mA */
75 #define CURRENT_MAX			30000
76 #define CURRENT_MIN			-30000
77 /* Power registers */
78 #define LTC2947_REG_POWER		0x93
79 #define LTC2947_REG_POWER_MAX		0x44
80 #define LTC2947_REG_POWER_MIN		0x46
81 #define LTC2947_REG_POWER_THRE_H	0x84
82 #define LTC2947_REG_POWER_THRE_L	0x86
83 /* in uW */
84 #define POWER_MAX			450000000
85 #define POWER_MIN			-450000000
86 /* Temperature registers */
87 #define LTC2947_REG_TEMP		0xA2
88 #define LTC2947_REG_TEMP_MAX		0x54
89 #define LTC2947_REG_TEMP_MIN		0x56
90 #define LTC2947_REG_TEMP_THRE_H		0x94
91 #define LTC2947_REG_TEMP_THRE_L		0x96
92 #define LTC2947_REG_TEMP_FAN_THRE_H	0x9C
93 #define LTC2947_REG_TEMP_FAN_THRE_L	0x9E
94 #define LTC2947_TEMP_FAN_CHAN		1
95 /* in millidegress Celsius */
96 #define TEMP_MAX			85000
97 #define TEMP_MIN			-40000
98 /* Energy registers */
99 #define LTC2947_REG_ENERGY1		0x06
100 #define LTC2947_REG_ENERGY2		0x16
101 /* Status/Alarm/Overflow registers */
102 #define LTC2947_REG_STATUS		0x80
103 #define LTC2947_REG_STATVT		0x81
104 #define LTC2947_REG_STATIP		0x82
105 #define LTC2947_REG_STATVDVCC		0x87
106 
107 #define LTC2947_ALERTS_SIZE	(LTC2947_REG_STATVDVCC - LTC2947_REG_STATUS)
108 #define LTC2947_MAX_VOLTAGE_MASK	BIT(0)
109 #define LTC2947_MIN_VOLTAGE_MASK	BIT(1)
110 #define LTC2947_MAX_CURRENT_MASK	BIT(0)
111 #define LTC2947_MIN_CURRENT_MASK	BIT(1)
112 #define LTC2947_MAX_POWER_MASK		BIT(2)
113 #define LTC2947_MIN_POWER_MASK		BIT(3)
114 #define LTC2947_MAX_TEMP_MASK		BIT(2)
115 #define LTC2947_MIN_TEMP_MASK		BIT(3)
116 #define LTC2947_MAX_TEMP_FAN_MASK	BIT(4)
117 #define LTC2947_MIN_TEMP_FAN_MASK	BIT(5)
118 
119 struct ltc2947_data {
120 	struct regmap *map;
121 	struct device *dev;
122 	/*
123 	 * The mutex is needed because the device has 2 memory pages. When
124 	 * reading/writing the correct page needs to be set so that, the
125 	 * complete sequence select_page->read/write needs to be protected.
126 	 */
127 	struct mutex lock;
128 	u32 lsb_energy;
129 	bool gpio_out;
130 };
131 
132 static int __ltc2947_val_read16(const struct ltc2947_data *st, const u8 reg,
133 				u64 *val)
134 {
135 	__be16 __val = 0;
136 	int ret;
137 
138 	ret = regmap_bulk_read(st->map, reg, &__val, 2);
139 	if (ret)
140 		return ret;
141 
142 	*val = be16_to_cpu(__val);
143 
144 	return 0;
145 }
146 
147 static int __ltc2947_val_read24(const struct ltc2947_data *st, const u8 reg,
148 				u64 *val)
149 {
150 	__be32 __val = 0;
151 	int ret;
152 
153 	ret = regmap_bulk_read(st->map, reg, &__val, 3);
154 	if (ret)
155 		return ret;
156 
157 	*val = be32_to_cpu(__val) >> 8;
158 
159 	return 0;
160 }
161 
162 static int __ltc2947_val_read64(const struct ltc2947_data *st, const u8 reg,
163 				u64 *val)
164 {
165 	__be64 __val = 0;
166 	int ret;
167 
168 	ret = regmap_bulk_read(st->map, reg, &__val, 6);
169 	if (ret)
170 		return ret;
171 
172 	*val = be64_to_cpu(__val) >> 16;
173 
174 	return 0;
175 }
176 
177 static int ltc2947_val_read(struct ltc2947_data *st, const u8 reg,
178 			    const u8 page, const size_t size, s64 *val)
179 {
180 	int ret;
181 	u64 __val = 0;
182 
183 	mutex_lock(&st->lock);
184 
185 	ret = regmap_write(st->map, LTC2947_REG_PAGE_CTRL, page);
186 	if (ret) {
187 		mutex_unlock(&st->lock);
188 		return ret;
189 	}
190 
191 	dev_dbg(st->dev, "Read val, reg:%02X, p:%d sz:%zu\n", reg, page,
192 		size);
193 
194 	switch (size) {
195 	case 2:
196 		ret = __ltc2947_val_read16(st, reg, &__val);
197 		break;
198 	case 3:
199 		ret = __ltc2947_val_read24(st, reg, &__val);
200 		break;
201 	case 6:
202 		ret = __ltc2947_val_read64(st, reg, &__val);
203 		break;
204 	default:
205 		ret = -EINVAL;
206 		break;
207 	}
208 
209 	mutex_unlock(&st->lock);
210 
211 	if (ret)
212 		return ret;
213 
214 	*val = sign_extend64(__val, (8 * size) - 1);
215 
216 	dev_dbg(st->dev, "Got s:%lld, u:%016llX\n", *val, __val);
217 
218 	return 0;
219 }
220 
221 static int __ltc2947_val_write64(const struct ltc2947_data *st, const u8 reg,
222 				 const u64 val)
223 {
224 	__be64 __val;
225 
226 	__val = cpu_to_be64(val << 16);
227 	return regmap_bulk_write(st->map, reg, &__val, 6);
228 }
229 
230 static int __ltc2947_val_write16(const struct ltc2947_data *st, const u8 reg,
231 				 const u16 val)
232 {
233 	__be16 __val;
234 
235 	__val = cpu_to_be16(val);
236 	return regmap_bulk_write(st->map, reg, &__val, 2);
237 }
238 
239 static int ltc2947_val_write(struct ltc2947_data *st, const u8 reg,
240 			     const u8 page, const size_t size, const u64 val)
241 {
242 	int ret;
243 
244 	mutex_lock(&st->lock);
245 	/* set device on correct page */
246 	ret = regmap_write(st->map, LTC2947_REG_PAGE_CTRL, page);
247 	if (ret) {
248 		mutex_unlock(&st->lock);
249 		return ret;
250 	}
251 
252 	dev_dbg(st->dev, "Write val, r:%02X, p:%d, sz:%zu, val:%016llX\n",
253 		reg, page, size, val);
254 
255 	switch (size) {
256 	case 2:
257 		ret = __ltc2947_val_write16(st, reg, val);
258 		break;
259 	case 6:
260 		ret = __ltc2947_val_write64(st, reg, val);
261 		break;
262 	default:
263 		ret = -EINVAL;
264 		break;
265 	}
266 
267 	mutex_unlock(&st->lock);
268 
269 	return ret;
270 }
271 
272 static int ltc2947_reset_history(struct ltc2947_data *st, const u8 reg_h,
273 				 const u8 reg_l)
274 {
275 	int ret;
276 	/*
277 	 * let's reset the tracking register's. Tracking register's have all
278 	 * 2 bytes size
279 	 */
280 	ret = ltc2947_val_write(st, reg_h, LTC2947_PAGE0, 2, 0x8000U);
281 	if (ret)
282 		return ret;
283 
284 	return ltc2947_val_write(st, reg_l, LTC2947_PAGE0, 2, 0x7FFFU);
285 }
286 
287 static int ltc2947_alarm_read(struct ltc2947_data *st, const u8 reg,
288 			      const u32 mask, long *val)
289 {
290 	u8 offset = reg - LTC2947_REG_STATUS;
291 	/* +1 to include status reg */
292 	char alarms[LTC2947_ALERTS_SIZE + 1];
293 	int ret = 0;
294 
295 	memset(alarms, 0, sizeof(alarms));
296 
297 	mutex_lock(&st->lock);
298 
299 	ret = regmap_write(st->map, LTC2947_REG_PAGE_CTRL, LTC2947_PAGE0);
300 	if (ret)
301 		goto unlock;
302 
303 	dev_dbg(st->dev, "Read alarm, reg:%02X, mask:%02X\n", reg, mask);
304 	/*
305 	 * As stated in the datasheet, when Threshold and Overflow registers
306 	 * are used, the status and all alert registers must be read in one
307 	 * multi-byte transaction.
308 	 */
309 	ret = regmap_bulk_read(st->map, LTC2947_REG_STATUS, alarms,
310 			       sizeof(alarms));
311 	if (ret)
312 		goto unlock;
313 
314 	/* get the alarm */
315 	*val = !!(alarms[offset] & mask);
316 unlock:
317 	mutex_unlock(&st->lock);
318 	return ret;
319 }
320 
321 static ssize_t ltc2947_show_value(struct device *dev,
322 				  struct device_attribute *da, char *buf)
323 {
324 	struct ltc2947_data *st = dev_get_drvdata(dev);
325 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
326 	int ret;
327 	s64 val = 0;
328 
329 	ret = ltc2947_val_read(st, attr->index, LTC2947_PAGE0, 6, &val);
330 	if (ret)
331 		return ret;
332 
333 	/* value in microJoule. st->lsb_energy was multiplied by 10E9 */
334 	val = div_s64(val * st->lsb_energy, 1000);
335 
336 	return sprintf(buf, "%lld\n", val);
337 }
338 
339 static int ltc2947_read_temp(struct device *dev, const u32 attr, long *val,
340 			     const int channel)
341 {
342 	int ret;
343 	struct ltc2947_data *st = dev_get_drvdata(dev);
344 	s64 __val = 0;
345 
346 	switch (attr) {
347 	case hwmon_temp_input:
348 		ret = ltc2947_val_read(st, LTC2947_REG_TEMP, LTC2947_PAGE0,
349 				       2, &__val);
350 		break;
351 	case hwmon_temp_highest:
352 		ret = ltc2947_val_read(st, LTC2947_REG_TEMP_MAX, LTC2947_PAGE0,
353 				       2, &__val);
354 		break;
355 	case hwmon_temp_lowest:
356 		ret = ltc2947_val_read(st, LTC2947_REG_TEMP_MIN, LTC2947_PAGE0,
357 				       2, &__val);
358 		break;
359 	case hwmon_temp_max_alarm:
360 		if (channel == LTC2947_TEMP_FAN_CHAN)
361 			return ltc2947_alarm_read(st, LTC2947_REG_STATVT,
362 						  LTC2947_MAX_TEMP_FAN_MASK,
363 						  val);
364 
365 		return ltc2947_alarm_read(st, LTC2947_REG_STATVT,
366 					  LTC2947_MAX_TEMP_MASK, val);
367 	case hwmon_temp_min_alarm:
368 		if (channel == LTC2947_TEMP_FAN_CHAN)
369 			return	ltc2947_alarm_read(st, LTC2947_REG_STATVT,
370 						   LTC2947_MIN_TEMP_FAN_MASK,
371 						   val);
372 
373 		return	ltc2947_alarm_read(st, LTC2947_REG_STATVT,
374 					   LTC2947_MIN_TEMP_MASK, val);
375 	case hwmon_temp_max:
376 		if (channel == LTC2947_TEMP_FAN_CHAN)
377 			ret = ltc2947_val_read(st, LTC2947_REG_TEMP_FAN_THRE_H,
378 					       LTC2947_PAGE1, 2, &__val);
379 		else
380 			ret = ltc2947_val_read(st, LTC2947_REG_TEMP_THRE_H,
381 					       LTC2947_PAGE1, 2, &__val);
382 		break;
383 	case hwmon_temp_min:
384 		if (channel == LTC2947_TEMP_FAN_CHAN)
385 			ret = ltc2947_val_read(st, LTC2947_REG_TEMP_FAN_THRE_L,
386 					       LTC2947_PAGE1, 2, &__val);
387 		else
388 			ret = ltc2947_val_read(st, LTC2947_REG_TEMP_THRE_L,
389 					       LTC2947_PAGE1, 2, &__val);
390 		break;
391 	default:
392 		return -ENOTSUPP;
393 	}
394 
395 	if (ret)
396 		return ret;
397 
398 	/* in milidegrees celcius, temp is given by: */
399 	*val = (__val * 204) + 550;
400 
401 	return 0;
402 }
403 
404 static int ltc2947_read_power(struct device *dev, const u32 attr, long *val)
405 {
406 	struct ltc2947_data *st = dev_get_drvdata(dev);
407 	int ret;
408 	u32 lsb = 200000; /* in uW */
409 	s64 __val = 0;
410 
411 	switch (attr) {
412 	case hwmon_power_input:
413 		ret = ltc2947_val_read(st, LTC2947_REG_POWER, LTC2947_PAGE0,
414 				       3, &__val);
415 		lsb = 50000;
416 		break;
417 	case hwmon_power_input_highest:
418 		ret = ltc2947_val_read(st, LTC2947_REG_POWER_MAX, LTC2947_PAGE0,
419 				       2, &__val);
420 		break;
421 	case hwmon_power_input_lowest:
422 		ret = ltc2947_val_read(st, LTC2947_REG_POWER_MIN, LTC2947_PAGE0,
423 				       2, &__val);
424 		break;
425 	case hwmon_power_max_alarm:
426 		return ltc2947_alarm_read(st, LTC2947_REG_STATIP,
427 					  LTC2947_MAX_POWER_MASK, val);
428 	case hwmon_power_min_alarm:
429 		return ltc2947_alarm_read(st, LTC2947_REG_STATIP,
430 					  LTC2947_MIN_POWER_MASK, val);
431 	case hwmon_power_max:
432 		ret = ltc2947_val_read(st, LTC2947_REG_POWER_THRE_H,
433 				       LTC2947_PAGE1, 2, &__val);
434 		break;
435 	case hwmon_power_min:
436 		ret = ltc2947_val_read(st, LTC2947_REG_POWER_THRE_L,
437 				       LTC2947_PAGE1, 2, &__val);
438 		break;
439 	default:
440 		return -ENOTSUPP;
441 	}
442 
443 	if (ret)
444 		return ret;
445 
446 	*val = __val * lsb;
447 
448 	return 0;
449 }
450 
451 static int ltc2947_read_curr(struct device *dev, const u32 attr, long *val)
452 {
453 	struct ltc2947_data *st = dev_get_drvdata(dev);
454 	int ret;
455 	u8 lsb = 12; /* in mA */
456 	s64 __val = 0;
457 
458 	switch (attr) {
459 	case hwmon_curr_input:
460 		ret = ltc2947_val_read(st, LTC2947_REG_CURRENT,
461 				       LTC2947_PAGE0, 3, &__val);
462 		lsb = 3;
463 		break;
464 	case hwmon_curr_highest:
465 		ret = ltc2947_val_read(st, LTC2947_REG_CURRENT_MAX,
466 				       LTC2947_PAGE0, 2, &__val);
467 		break;
468 	case hwmon_curr_lowest:
469 		ret = ltc2947_val_read(st, LTC2947_REG_CURRENT_MIN,
470 				       LTC2947_PAGE0, 2, &__val);
471 		break;
472 	case hwmon_curr_max_alarm:
473 		return ltc2947_alarm_read(st, LTC2947_REG_STATIP,
474 					  LTC2947_MAX_CURRENT_MASK, val);
475 	case hwmon_curr_min_alarm:
476 		return ltc2947_alarm_read(st, LTC2947_REG_STATIP,
477 					  LTC2947_MIN_CURRENT_MASK, val);
478 	case hwmon_curr_max:
479 		ret = ltc2947_val_read(st, LTC2947_REG_CURRENT_THRE_H,
480 				       LTC2947_PAGE1, 2, &__val);
481 		break;
482 	case hwmon_curr_min:
483 		ret = ltc2947_val_read(st, LTC2947_REG_CURRENT_THRE_L,
484 				       LTC2947_PAGE1, 2, &__val);
485 		break;
486 	default:
487 		return -ENOTSUPP;
488 	}
489 
490 	if (ret)
491 		return ret;
492 
493 	*val = __val * lsb;
494 
495 	return 0;
496 }
497 
498 static int ltc2947_read_in(struct device *dev, const u32 attr, long *val,
499 			   const int channel)
500 {
501 	struct ltc2947_data *st = dev_get_drvdata(dev);
502 	int ret;
503 	u8 lsb = 2; /* in mV */
504 	s64 __val = 0;
505 
506 	if (channel < 0 || channel > LTC2947_VOLTAGE_DVCC_CHAN) {
507 		dev_err(st->dev, "Invalid chan%d for voltage", channel);
508 		return -EINVAL;
509 	}
510 
511 	switch (attr) {
512 	case hwmon_in_input:
513 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
514 			ret = ltc2947_val_read(st, LTC2947_REG_DVCC,
515 					       LTC2947_PAGE0, 2, &__val);
516 			lsb = 145;
517 		} else {
518 			ret = ltc2947_val_read(st, LTC2947_REG_VOLTAGE,
519 					       LTC2947_PAGE0, 2, &__val);
520 		}
521 		break;
522 	case hwmon_in_highest:
523 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
524 			ret = ltc2947_val_read(st, LTC2947_REG_DVCC_MAX,
525 					       LTC2947_PAGE0, 2, &__val);
526 			lsb = 145;
527 		} else {
528 			ret = ltc2947_val_read(st, LTC2947_REG_VOLTAGE_MAX,
529 					       LTC2947_PAGE0, 2, &__val);
530 		}
531 		break;
532 	case hwmon_in_lowest:
533 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
534 			ret = ltc2947_val_read(st, LTC2947_REG_DVCC_MIN,
535 					       LTC2947_PAGE0, 2, &__val);
536 			lsb = 145;
537 		} else {
538 			ret = ltc2947_val_read(st, LTC2947_REG_VOLTAGE_MIN,
539 					       LTC2947_PAGE0, 2, &__val);
540 		}
541 		break;
542 	case hwmon_in_max_alarm:
543 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN)
544 			return ltc2947_alarm_read(st, LTC2947_REG_STATVDVCC,
545 						  LTC2947_MAX_VOLTAGE_MASK,
546 						  val);
547 
548 		return ltc2947_alarm_read(st, LTC2947_REG_STATVT,
549 					  LTC2947_MAX_VOLTAGE_MASK, val);
550 	case hwmon_in_min_alarm:
551 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN)
552 			return ltc2947_alarm_read(st, LTC2947_REG_STATVDVCC,
553 						  LTC2947_MIN_VOLTAGE_MASK,
554 						  val);
555 
556 		return ltc2947_alarm_read(st, LTC2947_REG_STATVT,
557 					  LTC2947_MIN_VOLTAGE_MASK, val);
558 	case hwmon_in_max:
559 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
560 			ret = ltc2947_val_read(st, LTC2947_REG_DVCC_THRE_H,
561 					       LTC2947_PAGE1, 2, &__val);
562 			lsb = 145;
563 		} else {
564 			ret = ltc2947_val_read(st, LTC2947_REG_VOLTAGE_THRE_H,
565 					       LTC2947_PAGE1, 2, &__val);
566 		}
567 		break;
568 	case hwmon_in_min:
569 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
570 			ret = ltc2947_val_read(st, LTC2947_REG_DVCC_THRE_L,
571 					       LTC2947_PAGE1, 2, &__val);
572 			lsb = 145;
573 		} else {
574 			ret = ltc2947_val_read(st, LTC2947_REG_VOLTAGE_THRE_L,
575 					       LTC2947_PAGE1, 2, &__val);
576 		}
577 		break;
578 	default:
579 		return -ENOTSUPP;
580 	}
581 
582 	if (ret)
583 		return ret;
584 
585 	*val = __val * lsb;
586 
587 	return 0;
588 }
589 
590 static int ltc2947_read(struct device *dev, enum hwmon_sensor_types type,
591 			u32 attr, int channel, long *val)
592 {
593 	switch (type) {
594 	case hwmon_in:
595 		return ltc2947_read_in(dev, attr, val, channel);
596 	case hwmon_curr:
597 		return ltc2947_read_curr(dev, attr, val);
598 	case hwmon_power:
599 		return ltc2947_read_power(dev, attr, val);
600 	case hwmon_temp:
601 		return ltc2947_read_temp(dev, attr, val, channel);
602 	default:
603 		return -ENOTSUPP;
604 	}
605 }
606 
607 static int ltc2947_write_temp(struct device *dev, const u32 attr,
608 			      long val, const int channel)
609 {
610 	struct ltc2947_data *st = dev_get_drvdata(dev);
611 
612 	if (channel < 0 || channel > LTC2947_TEMP_FAN_CHAN) {
613 		dev_err(st->dev, "Invalid chan%d for temperature", channel);
614 		return -EINVAL;
615 	}
616 
617 	switch (attr) {
618 	case hwmon_temp_reset_history:
619 		if (val != 1)
620 			return -EINVAL;
621 		return ltc2947_reset_history(st, LTC2947_REG_TEMP_MAX,
622 					     LTC2947_REG_TEMP_MIN);
623 	case hwmon_temp_max:
624 		val = clamp_val(val, TEMP_MIN, TEMP_MAX);
625 		if (channel == LTC2947_TEMP_FAN_CHAN) {
626 			if (!st->gpio_out)
627 				return -ENOTSUPP;
628 
629 			return ltc2947_val_write(st,
630 					LTC2947_REG_TEMP_FAN_THRE_H,
631 					LTC2947_PAGE1, 2,
632 					DIV_ROUND_CLOSEST(val - 550, 204));
633 		}
634 
635 		return ltc2947_val_write(st, LTC2947_REG_TEMP_THRE_H,
636 					 LTC2947_PAGE1, 2,
637 					 DIV_ROUND_CLOSEST(val - 550, 204));
638 	case hwmon_temp_min:
639 		val = clamp_val(val, TEMP_MIN, TEMP_MAX);
640 		if (channel == LTC2947_TEMP_FAN_CHAN) {
641 			if (!st->gpio_out)
642 				return -ENOTSUPP;
643 
644 			return ltc2947_val_write(st,
645 					LTC2947_REG_TEMP_FAN_THRE_L,
646 					LTC2947_PAGE1, 2,
647 					DIV_ROUND_CLOSEST(val - 550, 204));
648 		}
649 
650 		return ltc2947_val_write(st, LTC2947_REG_TEMP_THRE_L,
651 					 LTC2947_PAGE1, 2,
652 					 DIV_ROUND_CLOSEST(val - 550, 204));
653 	default:
654 		return -ENOTSUPP;
655 	}
656 }
657 
658 static int ltc2947_write_power(struct device *dev, const u32 attr,
659 			       long val)
660 {
661 	struct ltc2947_data *st = dev_get_drvdata(dev);
662 
663 	switch (attr) {
664 	case hwmon_power_reset_history:
665 		if (val != 1)
666 			return -EINVAL;
667 		return ltc2947_reset_history(st, LTC2947_REG_POWER_MAX,
668 					     LTC2947_REG_POWER_MIN);
669 	case hwmon_power_max:
670 		val = clamp_val(val, POWER_MIN, POWER_MAX);
671 		return ltc2947_val_write(st, LTC2947_REG_POWER_THRE_H,
672 					 LTC2947_PAGE1, 2,
673 					 DIV_ROUND_CLOSEST(val, 200000));
674 	case hwmon_power_min:
675 		val = clamp_val(val, POWER_MIN, POWER_MAX);
676 		return ltc2947_val_write(st, LTC2947_REG_POWER_THRE_L,
677 					 LTC2947_PAGE1, 2,
678 					 DIV_ROUND_CLOSEST(val, 200000));
679 	default:
680 		return -ENOTSUPP;
681 	}
682 }
683 
684 static int ltc2947_write_curr(struct device *dev, const u32 attr,
685 			      long val)
686 {
687 	struct ltc2947_data *st = dev_get_drvdata(dev);
688 
689 	switch (attr) {
690 	case hwmon_curr_reset_history:
691 		if (val != 1)
692 			return -EINVAL;
693 		return ltc2947_reset_history(st, LTC2947_REG_CURRENT_MAX,
694 					     LTC2947_REG_CURRENT_MIN);
695 	case hwmon_curr_max:
696 		val = clamp_val(val, CURRENT_MIN, CURRENT_MAX);
697 		return ltc2947_val_write(st, LTC2947_REG_CURRENT_THRE_H,
698 					 LTC2947_PAGE1, 2,
699 					 DIV_ROUND_CLOSEST(val, 12));
700 	case hwmon_curr_min:
701 		val = clamp_val(val, CURRENT_MIN, CURRENT_MAX);
702 		return ltc2947_val_write(st, LTC2947_REG_CURRENT_THRE_L,
703 					 LTC2947_PAGE1, 2,
704 					 DIV_ROUND_CLOSEST(val, 12));
705 	default:
706 		return -ENOTSUPP;
707 	}
708 }
709 
710 static int ltc2947_write_in(struct device *dev, const u32 attr, long val,
711 			    const int channel)
712 {
713 	struct ltc2947_data *st = dev_get_drvdata(dev);
714 
715 	if (channel > LTC2947_VOLTAGE_DVCC_CHAN) {
716 		dev_err(st->dev, "Invalid chan%d for voltage", channel);
717 		return -EINVAL;
718 	}
719 
720 	switch (attr) {
721 	case hwmon_in_reset_history:
722 		if (val != 1)
723 			return -EINVAL;
724 
725 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN)
726 			return ltc2947_reset_history(st, LTC2947_REG_DVCC_MAX,
727 						     LTC2947_REG_DVCC_MIN);
728 
729 		return ltc2947_reset_history(st, LTC2947_REG_VOLTAGE_MAX,
730 					     LTC2947_REG_VOLTAGE_MIN);
731 	case hwmon_in_max:
732 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
733 			val = clamp_val(val, VDVCC_MIN, VDVCC_MAX);
734 			return ltc2947_val_write(st, LTC2947_REG_DVCC_THRE_H,
735 						 LTC2947_PAGE1, 2,
736 						 DIV_ROUND_CLOSEST(val, 145));
737 		}
738 
739 		val = clamp_val(val, VOLTAGE_MIN, VOLTAGE_MAX);
740 		return ltc2947_val_write(st, LTC2947_REG_VOLTAGE_THRE_H,
741 					 LTC2947_PAGE1, 2,
742 					 DIV_ROUND_CLOSEST(val, 2));
743 	case hwmon_in_min:
744 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN) {
745 			val = clamp_val(val, VDVCC_MIN, VDVCC_MAX);
746 			return ltc2947_val_write(st, LTC2947_REG_DVCC_THRE_L,
747 						 LTC2947_PAGE1, 2,
748 						 DIV_ROUND_CLOSEST(val, 145));
749 		}
750 
751 		val = clamp_val(val, VOLTAGE_MIN, VOLTAGE_MAX);
752 		return ltc2947_val_write(st, LTC2947_REG_VOLTAGE_THRE_L,
753 					 LTC2947_PAGE1, 2,
754 					 DIV_ROUND_CLOSEST(val, 2));
755 	default:
756 		return -ENOTSUPP;
757 	}
758 }
759 
760 static int ltc2947_write(struct device *dev,
761 			 enum hwmon_sensor_types type,
762 			 u32 attr, int channel, long val)
763 {
764 	switch (type) {
765 	case hwmon_in:
766 		return ltc2947_write_in(dev, attr, val, channel);
767 	case hwmon_curr:
768 		return ltc2947_write_curr(dev, attr, val);
769 	case hwmon_power:
770 		return ltc2947_write_power(dev, attr, val);
771 	case hwmon_temp:
772 		return ltc2947_write_temp(dev, attr, val, channel);
773 	default:
774 		return -ENOTSUPP;
775 	}
776 }
777 
778 static int ltc2947_read_labels(struct device *dev,
779 			       enum hwmon_sensor_types type,
780 			       u32 attr, int channel, const char **str)
781 {
782 	switch (type) {
783 	case hwmon_in:
784 		if (channel == LTC2947_VOLTAGE_DVCC_CHAN)
785 			*str = "DVCC";
786 		else
787 			*str = "VP-VM";
788 		return 0;
789 	case hwmon_curr:
790 		*str = "IP-IM";
791 		return 0;
792 	case hwmon_temp:
793 		if (channel == LTC2947_TEMP_FAN_CHAN)
794 			*str = "TEMPFAN";
795 		else
796 			*str = "Ambient";
797 		return 0;
798 	case hwmon_power:
799 		*str = "Power";
800 		return 0;
801 	default:
802 		return -ENOTSUPP;
803 	}
804 }
805 
806 static int ltc2947_in_is_visible(const u32 attr)
807 {
808 	switch (attr) {
809 	case hwmon_in_input:
810 	case hwmon_in_highest:
811 	case hwmon_in_lowest:
812 	case hwmon_in_max_alarm:
813 	case hwmon_in_min_alarm:
814 	case hwmon_in_label:
815 		return 0444;
816 	case hwmon_in_reset_history:
817 		return 0200;
818 	case hwmon_in_max:
819 	case hwmon_in_min:
820 		return 0644;
821 	default:
822 		return 0;
823 	}
824 }
825 
826 static int ltc2947_curr_is_visible(const u32 attr)
827 {
828 	switch (attr) {
829 	case hwmon_curr_input:
830 	case hwmon_curr_highest:
831 	case hwmon_curr_lowest:
832 	case hwmon_curr_max_alarm:
833 	case hwmon_curr_min_alarm:
834 	case hwmon_curr_label:
835 		return 0444;
836 	case hwmon_curr_reset_history:
837 		return 0200;
838 	case hwmon_curr_max:
839 	case hwmon_curr_min:
840 		return 0644;
841 	default:
842 		return 0;
843 	}
844 }
845 
846 static int ltc2947_power_is_visible(const u32 attr)
847 {
848 	switch (attr) {
849 	case hwmon_power_input:
850 	case hwmon_power_input_highest:
851 	case hwmon_power_input_lowest:
852 	case hwmon_power_label:
853 	case hwmon_power_max_alarm:
854 	case hwmon_power_min_alarm:
855 		return 0444;
856 	case hwmon_power_reset_history:
857 		return 0200;
858 	case hwmon_power_max:
859 	case hwmon_power_min:
860 		return 0644;
861 	default:
862 		return 0;
863 	}
864 }
865 
866 static int ltc2947_temp_is_visible(const u32 attr)
867 {
868 	switch (attr) {
869 	case hwmon_temp_input:
870 	case hwmon_temp_highest:
871 	case hwmon_temp_lowest:
872 	case hwmon_temp_max_alarm:
873 	case hwmon_temp_min_alarm:
874 	case hwmon_temp_label:
875 		return 0444;
876 	case hwmon_temp_reset_history:
877 		return 0200;
878 	case hwmon_temp_max:
879 	case hwmon_temp_min:
880 		return 0644;
881 	default:
882 		return 0;
883 	}
884 }
885 
886 static umode_t ltc2947_is_visible(const void *data,
887 				  enum hwmon_sensor_types type,
888 				  u32 attr, int channel)
889 {
890 	switch (type) {
891 	case hwmon_in:
892 		return ltc2947_in_is_visible(attr);
893 	case hwmon_curr:
894 		return ltc2947_curr_is_visible(attr);
895 	case hwmon_power:
896 		return ltc2947_power_is_visible(attr);
897 	case hwmon_temp:
898 		return ltc2947_temp_is_visible(attr);
899 	default:
900 		return 0;
901 	}
902 }
903 
904 static const struct hwmon_channel_info *ltc2947_info[] = {
905 	HWMON_CHANNEL_INFO(in,
906 			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
907 			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_RESET_HISTORY |
908 			   HWMON_I_MIN_ALARM | HWMON_I_MAX_ALARM |
909 			   HWMON_I_LABEL,
910 			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
911 			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_RESET_HISTORY |
912 			   HWMON_I_MIN_ALARM | HWMON_I_MAX_ALARM |
913 			   HWMON_I_LABEL),
914 	HWMON_CHANNEL_INFO(curr,
915 			   HWMON_C_INPUT | HWMON_C_LOWEST | HWMON_C_HIGHEST |
916 			   HWMON_C_MAX | HWMON_C_MIN | HWMON_C_RESET_HISTORY |
917 			   HWMON_C_MIN_ALARM | HWMON_C_MAX_ALARM |
918 			   HWMON_C_LABEL),
919 	HWMON_CHANNEL_INFO(power,
920 			   HWMON_P_INPUT | HWMON_P_INPUT_LOWEST |
921 			   HWMON_P_INPUT_HIGHEST | HWMON_P_MAX | HWMON_P_MIN |
922 			   HWMON_P_RESET_HISTORY | HWMON_P_MAX_ALARM |
923 			   HWMON_P_MIN_ALARM | HWMON_P_LABEL),
924 	HWMON_CHANNEL_INFO(temp,
925 			   HWMON_T_INPUT | HWMON_T_LOWEST | HWMON_T_HIGHEST |
926 			   HWMON_T_MAX | HWMON_T_MIN | HWMON_T_RESET_HISTORY |
927 			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
928 			   HWMON_T_LABEL,
929 			   HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM | HWMON_T_MAX |
930 			   HWMON_T_MIN | HWMON_T_LABEL),
931 	NULL
932 };
933 
934 static const struct hwmon_ops ltc2947_hwmon_ops = {
935 	.is_visible = ltc2947_is_visible,
936 	.read = ltc2947_read,
937 	.write = ltc2947_write,
938 	.read_string = ltc2947_read_labels,
939 };
940 
941 static const struct hwmon_chip_info ltc2947_chip_info = {
942 	.ops = &ltc2947_hwmon_ops,
943 	.info = ltc2947_info,
944 };
945 
946 /* energy attributes are 6bytes wide so we need u64 */
947 static SENSOR_DEVICE_ATTR(energy1_input, 0444, ltc2947_show_value, NULL,
948 			  LTC2947_REG_ENERGY1);
949 static SENSOR_DEVICE_ATTR(energy2_input, 0444, ltc2947_show_value, NULL,
950 			  LTC2947_REG_ENERGY2);
951 
952 static struct attribute *ltc2947_attrs[] = {
953 	&sensor_dev_attr_energy1_input.dev_attr.attr,
954 	&sensor_dev_attr_energy2_input.dev_attr.attr,
955 	NULL,
956 };
957 ATTRIBUTE_GROUPS(ltc2947);
958 
959 static int ltc2947_setup(struct ltc2947_data *st)
960 {
961 	int ret;
962 	struct clk *extclk;
963 	u32 dummy, deadband, pol;
964 	u32 accum[2];
965 
966 	/* clear status register by reading it */
967 	ret = regmap_read(st->map, LTC2947_REG_STATUS, &dummy);
968 	if (ret)
969 		return ret;
970 	/*
971 	 * Set max/min for power here since the default values x scale
972 	 * would overflow on 32bit arch
973 	 */
974 	ret = ltc2947_val_write(st, LTC2947_REG_POWER_THRE_H, LTC2947_PAGE1, 2,
975 				POWER_MAX / 200000);
976 	if (ret)
977 		return ret;
978 
979 	ret = ltc2947_val_write(st, LTC2947_REG_POWER_THRE_L, LTC2947_PAGE1, 2,
980 				POWER_MIN / 200000);
981 	if (ret)
982 		return ret;
983 
984 	/* check external clock presence */
985 	extclk = devm_clk_get_optional_enabled(st->dev, NULL);
986 	if (IS_ERR(extclk))
987 		return dev_err_probe(st->dev, PTR_ERR(extclk),
988 				     "Failed to get external clock\n");
989 
990 	if (extclk) {
991 		unsigned long rate_hz;
992 		u8 pre = 0, div, tbctl;
993 		u64 aux;
994 
995 		/* let's calculate and set the right valus in TBCTL */
996 		rate_hz = clk_get_rate(extclk);
997 		if (rate_hz < LTC2947_CLK_MIN || rate_hz > LTC2947_CLK_MAX) {
998 			dev_err(st->dev, "Invalid rate:%lu for external clock",
999 				rate_hz);
1000 			return -EINVAL;
1001 		}
1002 
1003 		/* as in table 1 of the datasheet */
1004 		if (rate_hz >= LTC2947_CLK_MIN && rate_hz <= 1000000)
1005 			pre = 0;
1006 		else if (rate_hz > 1000000 && rate_hz <= 2000000)
1007 			pre = 1;
1008 		else if (rate_hz > 2000000 && rate_hz <= 4000000)
1009 			pre = 2;
1010 		else if (rate_hz > 4000000 && rate_hz <= 8000000)
1011 			pre = 3;
1012 		else if (rate_hz > 8000000 && rate_hz <= 16000000)
1013 			pre = 4;
1014 		else if (rate_hz > 16000000 && rate_hz <= LTC2947_CLK_MAX)
1015 			pre = 5;
1016 		/*
1017 		 * Div is given by:
1018 		 *	floor(fref / (2^PRE * 32768))
1019 		 */
1020 		div = rate_hz / ((1 << pre) * 32768);
1021 		tbctl = LTC2947_PRE(pre) | LTC2947_DIV(div);
1022 
1023 		ret = regmap_write(st->map, LTC2947_REG_TBCTL, tbctl);
1024 		if (ret)
1025 			return ret;
1026 		/*
1027 		 * The energy lsb is given by (in W*s):
1028 		 *      06416 * (1/fref) * 2^PRE * (DIV + 1)
1029 		 * The value is multiplied by 10E9
1030 		 */
1031 		aux = (div + 1) * ((1 << pre) * 641600000ULL);
1032 		st->lsb_energy = DIV_ROUND_CLOSEST_ULL(aux, rate_hz);
1033 	} else {
1034 		/* 19.89E-6 * 10E9 */
1035 		st->lsb_energy = 19890;
1036 	}
1037 	ret = of_property_read_u32_array(st->dev->of_node,
1038 					 "adi,accumulator-ctl-pol", accum,
1039 					  ARRAY_SIZE(accum));
1040 	if (!ret) {
1041 		u32 accum_reg = LTC2947_ACCUM_POL_1(accum[0]) |
1042 				LTC2947_ACCUM_POL_2(accum[1]);
1043 
1044 		ret = regmap_write(st->map, LTC2947_REG_ACCUM_POL, accum_reg);
1045 		if (ret)
1046 			return ret;
1047 	}
1048 	ret = of_property_read_u32(st->dev->of_node,
1049 				   "adi,accumulation-deadband-microamp",
1050 				   &deadband);
1051 	if (!ret) {
1052 		/* the LSB is the same as the current, so 3mA */
1053 		ret = regmap_write(st->map, LTC2947_REG_ACCUM_DEADBAND,
1054 				   deadband / (1000 * 3));
1055 		if (ret)
1056 			return ret;
1057 	}
1058 	/* check gpio cfg */
1059 	ret = of_property_read_u32(st->dev->of_node, "adi,gpio-out-pol", &pol);
1060 	if (!ret) {
1061 		/* setup GPIO as output */
1062 		u32 gpio_ctl = LTC2947_GPIO_EN(1) | LTC2947_GPIO_FAN_EN(1) |
1063 			LTC2947_GPIO_FAN_POL(pol);
1064 
1065 		st->gpio_out = true;
1066 		ret = regmap_write(st->map, LTC2947_REG_GPIOSTATCTL, gpio_ctl);
1067 		if (ret)
1068 			return ret;
1069 	}
1070 	ret = of_property_read_u32_array(st->dev->of_node, "adi,gpio-in-accum",
1071 					 accum, ARRAY_SIZE(accum));
1072 	if (!ret) {
1073 		/*
1074 		 * Setup the accum options. The gpioctl is already defined as
1075 		 * input by default.
1076 		 */
1077 		u32 accum_val = LTC2947_ACCUM_POL_1(accum[0]) |
1078 				LTC2947_ACCUM_POL_2(accum[1]);
1079 
1080 		if (st->gpio_out) {
1081 			dev_err(st->dev,
1082 				"Cannot have input gpio config if already configured as output");
1083 			return -EINVAL;
1084 		}
1085 
1086 		ret = regmap_write(st->map, LTC2947_REG_GPIO_ACCUM, accum_val);
1087 		if (ret)
1088 			return ret;
1089 	}
1090 
1091 	/* set continuos mode */
1092 	return regmap_update_bits(st->map, LTC2947_REG_CTRL,
1093 				  LTC2947_CONT_MODE_MASK, LTC2947_CONT_MODE(1));
1094 }
1095 
1096 int ltc2947_core_probe(struct regmap *map, const char *name)
1097 {
1098 	struct ltc2947_data *st;
1099 	struct device *dev = regmap_get_device(map);
1100 	struct device *hwmon;
1101 	int ret;
1102 
1103 	st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
1104 	if (!st)
1105 		return -ENOMEM;
1106 
1107 	st->map = map;
1108 	st->dev = dev;
1109 	dev_set_drvdata(dev, st);
1110 	mutex_init(&st->lock);
1111 
1112 	ret = ltc2947_setup(st);
1113 	if (ret)
1114 		return ret;
1115 
1116 	hwmon = devm_hwmon_device_register_with_info(dev, name, st,
1117 						     &ltc2947_chip_info,
1118 						     ltc2947_groups);
1119 	return PTR_ERR_OR_ZERO(hwmon);
1120 }
1121 EXPORT_SYMBOL_GPL(ltc2947_core_probe);
1122 
1123 static int ltc2947_resume(struct device *dev)
1124 {
1125 	struct ltc2947_data *st = dev_get_drvdata(dev);
1126 	u32 ctrl = 0;
1127 	int ret;
1128 
1129 	/* dummy read to wake the device */
1130 	ret = regmap_read(st->map, LTC2947_REG_CTRL, &ctrl);
1131 	if (ret)
1132 		return ret;
1133 	/*
1134 	 * Wait for the device. It takes 100ms to wake up so, 10ms extra
1135 	 * should be enough.
1136 	 */
1137 	msleep(110);
1138 	ret = regmap_read(st->map, LTC2947_REG_CTRL, &ctrl);
1139 	if (ret)
1140 		return ret;
1141 	/* ctrl should be 0 */
1142 	if (ctrl != 0) {
1143 		dev_err(st->dev, "Device failed to wake up, ctl:%02X\n", ctrl);
1144 		return -ETIMEDOUT;
1145 	}
1146 
1147 	/* set continuous mode */
1148 	return regmap_update_bits(st->map, LTC2947_REG_CTRL,
1149 				  LTC2947_CONT_MODE_MASK, LTC2947_CONT_MODE(1));
1150 }
1151 
1152 static int ltc2947_suspend(struct device *dev)
1153 {
1154 	struct ltc2947_data *st = dev_get_drvdata(dev);
1155 
1156 	return regmap_update_bits(st->map, LTC2947_REG_CTRL,
1157 				  LTC2947_SHUTDOWN_MASK, 1);
1158 }
1159 
1160 EXPORT_SIMPLE_DEV_PM_OPS(ltc2947_pm_ops, ltc2947_suspend, ltc2947_resume);
1161 
1162 const struct of_device_id ltc2947_of_match[] = {
1163 	{ .compatible = "adi,ltc2947" },
1164 	{}
1165 };
1166 EXPORT_SYMBOL_GPL(ltc2947_of_match);
1167 MODULE_DEVICE_TABLE(of, ltc2947_of_match);
1168 
1169 MODULE_AUTHOR("Nuno Sa <nuno.sa@analog.com>");
1170 MODULE_DESCRIPTION("LTC2947 power and energy monitor core driver");
1171 MODULE_LICENSE("GPL");
1172