1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Fuel gauge driver for Maxim 17042 / 8966 / 8997
4 //  Note that Maxim 8966 and 8997 are mfd and this is its subdevice.
5 //
6 // Copyright (C) 2011 Samsung Electronics
7 // MyungJoo Ham <myungjoo.ham@samsung.com>
8 //
9 // This driver is based on max17040_battery.c
10 
11 #include <linux/acpi.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/i2c.h>
16 #include <linux/delay.h>
17 #include <linux/interrupt.h>
18 #include <linux/pm.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/power_supply.h>
21 #include <linux/power/max17042_battery.h>
22 #include <linux/of.h>
23 #include <linux/regmap.h>
24 
25 /* Status register bits */
26 #define STATUS_POR_BIT         (1 << 1)
27 #define STATUS_BST_BIT         (1 << 3)
28 #define STATUS_VMN_BIT         (1 << 8)
29 #define STATUS_TMN_BIT         (1 << 9)
30 #define STATUS_SMN_BIT         (1 << 10)
31 #define STATUS_BI_BIT          (1 << 11)
32 #define STATUS_VMX_BIT         (1 << 12)
33 #define STATUS_TMX_BIT         (1 << 13)
34 #define STATUS_SMX_BIT         (1 << 14)
35 #define STATUS_BR_BIT          (1 << 15)
36 
37 /* Interrupt mask bits */
38 #define CONFIG_ALRT_BIT_ENBL	(1 << 2)
39 #define STATUS_INTR_SOCMIN_BIT	(1 << 10)
40 #define STATUS_INTR_SOCMAX_BIT	(1 << 14)
41 
42 #define VFSOC0_LOCK		0x0000
43 #define VFSOC0_UNLOCK		0x0080
44 #define MODEL_UNLOCK1	0X0059
45 #define MODEL_UNLOCK2	0X00C4
46 #define MODEL_LOCK1		0X0000
47 #define MODEL_LOCK2		0X0000
48 
49 #define dQ_ACC_DIV	0x4
50 #define dP_ACC_100	0x1900
51 #define dP_ACC_200	0x3200
52 
53 #define MAX17042_VMAX_TOLERANCE		50 /* 50 mV */
54 
55 struct max17042_chip {
56 	struct i2c_client *client;
57 	struct regmap *regmap;
58 	struct power_supply *battery;
59 	enum max170xx_chip_type chip_type;
60 	struct max17042_platform_data *pdata;
61 	struct work_struct work;
62 	int    init_complete;
63 };
64 
65 static enum power_supply_property max17042_battery_props[] = {
66 	POWER_SUPPLY_PROP_STATUS,
67 	POWER_SUPPLY_PROP_PRESENT,
68 	POWER_SUPPLY_PROP_TECHNOLOGY,
69 	POWER_SUPPLY_PROP_CYCLE_COUNT,
70 	POWER_SUPPLY_PROP_VOLTAGE_MAX,
71 	POWER_SUPPLY_PROP_VOLTAGE_MIN,
72 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
73 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
74 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
75 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
76 	POWER_SUPPLY_PROP_CAPACITY,
77 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
78 	POWER_SUPPLY_PROP_CHARGE_FULL,
79 	POWER_SUPPLY_PROP_CHARGE_NOW,
80 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
81 	POWER_SUPPLY_PROP_TEMP,
82 	POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
83 	POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
84 	POWER_SUPPLY_PROP_TEMP_MIN,
85 	POWER_SUPPLY_PROP_TEMP_MAX,
86 	POWER_SUPPLY_PROP_HEALTH,
87 	POWER_SUPPLY_PROP_SCOPE,
88 	POWER_SUPPLY_PROP_CURRENT_NOW,
89 	POWER_SUPPLY_PROP_CURRENT_AVG,
90 };
91 
92 static int max17042_get_temperature(struct max17042_chip *chip, int *temp)
93 {
94 	int ret;
95 	u32 data;
96 	struct regmap *map = chip->regmap;
97 
98 	ret = regmap_read(map, MAX17042_TEMP, &data);
99 	if (ret < 0)
100 		return ret;
101 
102 	*temp = sign_extend32(data, 15);
103 	/* The value is converted into deci-centigrade scale */
104 	/* Units of LSB = 1 / 256 degree Celsius */
105 	*temp = *temp * 10 / 256;
106 	return 0;
107 }
108 
109 static int max17042_get_status(struct max17042_chip *chip, int *status)
110 {
111 	int ret, charge_full, charge_now;
112 	int avg_current;
113 	u32 data;
114 
115 	ret = power_supply_am_i_supplied(chip->battery);
116 	if (ret < 0) {
117 		*status = POWER_SUPPLY_STATUS_UNKNOWN;
118 		return 0;
119 	}
120 	if (ret == 0) {
121 		*status = POWER_SUPPLY_STATUS_DISCHARGING;
122 		return 0;
123 	}
124 
125 	/*
126 	 * The MAX170xx has builtin end-of-charge detection and will update
127 	 * FullCAP to match RepCap when it detects end of charging.
128 	 *
129 	 * When this cycle the battery gets charged to a higher (calculated)
130 	 * capacity then the previous cycle then FullCAP will get updated
131 	 * contineously once end-of-charge detection kicks in, so allow the
132 	 * 2 to differ a bit.
133 	 */
134 
135 	ret = regmap_read(chip->regmap, MAX17042_FullCAP, &charge_full);
136 	if (ret < 0)
137 		return ret;
138 
139 	ret = regmap_read(chip->regmap, MAX17042_RepCap, &charge_now);
140 	if (ret < 0)
141 		return ret;
142 
143 	if ((charge_full - charge_now) <= MAX17042_FULL_THRESHOLD) {
144 		*status = POWER_SUPPLY_STATUS_FULL;
145 		return 0;
146 	}
147 
148 	/*
149 	 * Even though we are supplied, we may still be discharging if the
150 	 * supply is e.g. only delivering 5V 0.5A. Check current if available.
151 	 */
152 	if (!chip->pdata->enable_current_sense) {
153 		*status = POWER_SUPPLY_STATUS_CHARGING;
154 		return 0;
155 	}
156 
157 	ret = regmap_read(chip->regmap, MAX17042_AvgCurrent, &data);
158 	if (ret < 0)
159 		return ret;
160 
161 	avg_current = sign_extend32(data, 15);
162 	avg_current *= 1562500 / chip->pdata->r_sns;
163 
164 	if (avg_current > 0)
165 		*status = POWER_SUPPLY_STATUS_CHARGING;
166 	else
167 		*status = POWER_SUPPLY_STATUS_DISCHARGING;
168 
169 	return 0;
170 }
171 
172 static int max17042_get_battery_health(struct max17042_chip *chip, int *health)
173 {
174 	int temp, vavg, vbatt, ret;
175 	u32 val;
176 
177 	ret = regmap_read(chip->regmap, MAX17042_AvgVCELL, &val);
178 	if (ret < 0)
179 		goto health_error;
180 
181 	/* bits [0-3] unused */
182 	vavg = val * 625 / 8;
183 	/* Convert to millivolts */
184 	vavg /= 1000;
185 
186 	ret = regmap_read(chip->regmap, MAX17042_VCELL, &val);
187 	if (ret < 0)
188 		goto health_error;
189 
190 	/* bits [0-3] unused */
191 	vbatt = val * 625 / 8;
192 	/* Convert to millivolts */
193 	vbatt /= 1000;
194 
195 	if (vavg < chip->pdata->vmin) {
196 		*health = POWER_SUPPLY_HEALTH_DEAD;
197 		goto out;
198 	}
199 
200 	if (vbatt > chip->pdata->vmax + MAX17042_VMAX_TOLERANCE) {
201 		*health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
202 		goto out;
203 	}
204 
205 	ret = max17042_get_temperature(chip, &temp);
206 	if (ret < 0)
207 		goto health_error;
208 
209 	if (temp < chip->pdata->temp_min) {
210 		*health = POWER_SUPPLY_HEALTH_COLD;
211 		goto out;
212 	}
213 
214 	if (temp > chip->pdata->temp_max) {
215 		*health = POWER_SUPPLY_HEALTH_OVERHEAT;
216 		goto out;
217 	}
218 
219 	*health = POWER_SUPPLY_HEALTH_GOOD;
220 
221 out:
222 	return 0;
223 
224 health_error:
225 	return ret;
226 }
227 
228 static int max17042_get_property(struct power_supply *psy,
229 			    enum power_supply_property psp,
230 			    union power_supply_propval *val)
231 {
232 	struct max17042_chip *chip = power_supply_get_drvdata(psy);
233 	struct regmap *map = chip->regmap;
234 	int ret;
235 	u32 data;
236 	u64 data64;
237 
238 	if (!chip->init_complete)
239 		return -EAGAIN;
240 
241 	switch (psp) {
242 	case POWER_SUPPLY_PROP_STATUS:
243 		ret = max17042_get_status(chip, &val->intval);
244 		if (ret < 0)
245 			return ret;
246 		break;
247 	case POWER_SUPPLY_PROP_PRESENT:
248 		ret = regmap_read(map, MAX17042_STATUS, &data);
249 		if (ret < 0)
250 			return ret;
251 
252 		if (data & MAX17042_STATUS_BattAbsent)
253 			val->intval = 0;
254 		else
255 			val->intval = 1;
256 		break;
257 	case POWER_SUPPLY_PROP_TECHNOLOGY:
258 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
259 		break;
260 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
261 		ret = regmap_read(map, MAX17042_Cycles, &data);
262 		if (ret < 0)
263 			return ret;
264 
265 		val->intval = data;
266 		break;
267 	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
268 		ret = regmap_read(map, MAX17042_MinMaxVolt, &data);
269 		if (ret < 0)
270 			return ret;
271 
272 		val->intval = data >> 8;
273 		val->intval *= 20000; /* Units of LSB = 20mV */
274 		break;
275 	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
276 		ret = regmap_read(map, MAX17042_MinMaxVolt, &data);
277 		if (ret < 0)
278 			return ret;
279 
280 		val->intval = (data & 0xff) * 20000; /* Units of 20mV */
281 		break;
282 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
283 		if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
284 			ret = regmap_read(map, MAX17042_V_empty, &data);
285 		else
286 			ret = regmap_read(map, MAX17047_V_empty, &data);
287 		if (ret < 0)
288 			return ret;
289 
290 		val->intval = data >> 7;
291 		val->intval *= 10000; /* Units of LSB = 10mV */
292 		break;
293 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
294 		ret = regmap_read(map, MAX17042_VCELL, &data);
295 		if (ret < 0)
296 			return ret;
297 
298 		val->intval = data * 625 / 8;
299 		break;
300 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
301 		ret = regmap_read(map, MAX17042_AvgVCELL, &data);
302 		if (ret < 0)
303 			return ret;
304 
305 		val->intval = data * 625 / 8;
306 		break;
307 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
308 		ret = regmap_read(map, MAX17042_OCVInternal, &data);
309 		if (ret < 0)
310 			return ret;
311 
312 		val->intval = data * 625 / 8;
313 		break;
314 	case POWER_SUPPLY_PROP_CAPACITY:
315 		ret = regmap_read(map, MAX17042_RepSOC, &data);
316 		if (ret < 0)
317 			return ret;
318 
319 		val->intval = data >> 8;
320 		break;
321 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
322 		ret = regmap_read(map, MAX17042_DesignCap, &data);
323 		if (ret < 0)
324 			return ret;
325 
326 		data64 = data * 5000000ll;
327 		do_div(data64, chip->pdata->r_sns);
328 		val->intval = data64;
329 		break;
330 	case POWER_SUPPLY_PROP_CHARGE_FULL:
331 		ret = regmap_read(map, MAX17042_FullCAP, &data);
332 		if (ret < 0)
333 			return ret;
334 
335 		data64 = data * 5000000ll;
336 		do_div(data64, chip->pdata->r_sns);
337 		val->intval = data64;
338 		break;
339 	case POWER_SUPPLY_PROP_CHARGE_NOW:
340 		ret = regmap_read(map, MAX17042_RepCap, &data);
341 		if (ret < 0)
342 			return ret;
343 
344 		data64 = data * 5000000ll;
345 		do_div(data64, chip->pdata->r_sns);
346 		val->intval = data64;
347 		break;
348 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
349 		ret = regmap_read(map, MAX17042_QH, &data);
350 		if (ret < 0)
351 			return ret;
352 
353 		val->intval = data * 1000 / 2;
354 		break;
355 	case POWER_SUPPLY_PROP_TEMP:
356 		ret = max17042_get_temperature(chip, &val->intval);
357 		if (ret < 0)
358 			return ret;
359 		break;
360 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
361 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
362 		if (ret < 0)
363 			return ret;
364 		/* LSB is Alert Minimum. In deci-centigrade */
365 		val->intval = sign_extend32(data & 0xff, 7) * 10;
366 		break;
367 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
368 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
369 		if (ret < 0)
370 			return ret;
371 		/* MSB is Alert Maximum. In deci-centigrade */
372 		val->intval = sign_extend32(data >> 8, 7) * 10;
373 		break;
374 	case POWER_SUPPLY_PROP_TEMP_MIN:
375 		val->intval = chip->pdata->temp_min;
376 		break;
377 	case POWER_SUPPLY_PROP_TEMP_MAX:
378 		val->intval = chip->pdata->temp_max;
379 		break;
380 	case POWER_SUPPLY_PROP_HEALTH:
381 		ret = max17042_get_battery_health(chip, &val->intval);
382 		if (ret < 0)
383 			return ret;
384 		break;
385 	case POWER_SUPPLY_PROP_SCOPE:
386 		val->intval = POWER_SUPPLY_SCOPE_SYSTEM;
387 		break;
388 	case POWER_SUPPLY_PROP_CURRENT_NOW:
389 		if (chip->pdata->enable_current_sense) {
390 			ret = regmap_read(map, MAX17042_Current, &data);
391 			if (ret < 0)
392 				return ret;
393 
394 			val->intval = sign_extend32(data, 15);
395 			val->intval *= 1562500 / chip->pdata->r_sns;
396 		} else {
397 			return -EINVAL;
398 		}
399 		break;
400 	case POWER_SUPPLY_PROP_CURRENT_AVG:
401 		if (chip->pdata->enable_current_sense) {
402 			ret = regmap_read(map, MAX17042_AvgCurrent, &data);
403 			if (ret < 0)
404 				return ret;
405 
406 			val->intval = sign_extend32(data, 15);
407 			val->intval *= 1562500 / chip->pdata->r_sns;
408 		} else {
409 			return -EINVAL;
410 		}
411 		break;
412 	default:
413 		return -EINVAL;
414 	}
415 	return 0;
416 }
417 
418 static int max17042_set_property(struct power_supply *psy,
419 			    enum power_supply_property psp,
420 			    const union power_supply_propval *val)
421 {
422 	struct max17042_chip *chip = power_supply_get_drvdata(psy);
423 	struct regmap *map = chip->regmap;
424 	int ret = 0;
425 	u32 data;
426 	int8_t temp;
427 
428 	switch (psp) {
429 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
430 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
431 		if (ret < 0)
432 			return ret;
433 
434 		/* Input in deci-centigrade, convert to centigrade */
435 		temp = val->intval / 10;
436 		/* force min < max */
437 		if (temp >= (int8_t)(data >> 8))
438 			temp = (int8_t)(data >> 8) - 1;
439 		/* Write both MAX and MIN ALERT */
440 		data = (data & 0xff00) + temp;
441 		ret = regmap_write(map, MAX17042_TALRT_Th, data);
442 		break;
443 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
444 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
445 		if (ret < 0)
446 			return ret;
447 
448 		/* Input in Deci-Centigrade, convert to centigrade */
449 		temp = val->intval / 10;
450 		/* force max > min */
451 		if (temp <= (int8_t)(data & 0xff))
452 			temp = (int8_t)(data & 0xff) + 1;
453 		/* Write both MAX and MIN ALERT */
454 		data = (data & 0xff) + (temp << 8);
455 		ret = regmap_write(map, MAX17042_TALRT_Th, data);
456 		break;
457 	default:
458 		ret = -EINVAL;
459 	}
460 
461 	return ret;
462 }
463 
464 static int max17042_property_is_writeable(struct power_supply *psy,
465 		enum power_supply_property psp)
466 {
467 	int ret;
468 
469 	switch (psp) {
470 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
471 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
472 		ret = 1;
473 		break;
474 	default:
475 		ret = 0;
476 	}
477 
478 	return ret;
479 }
480 
481 static void max17042_external_power_changed(struct power_supply *psy)
482 {
483 	power_supply_changed(psy);
484 }
485 
486 static int max17042_write_verify_reg(struct regmap *map, u8 reg, u32 value)
487 {
488 	int retries = 8;
489 	int ret;
490 	u32 read_value;
491 
492 	do {
493 		ret = regmap_write(map, reg, value);
494 		regmap_read(map, reg, &read_value);
495 		if (read_value != value) {
496 			ret = -EIO;
497 			retries--;
498 		}
499 	} while (retries && read_value != value);
500 
501 	if (ret < 0)
502 		pr_err("%s: err %d\n", __func__, ret);
503 
504 	return ret;
505 }
506 
507 static inline void max17042_override_por(struct regmap *map,
508 					 u8 reg, u16 value)
509 {
510 	if (value)
511 		regmap_write(map, reg, value);
512 }
513 
514 static inline void max10742_unlock_model(struct max17042_chip *chip)
515 {
516 	struct regmap *map = chip->regmap;
517 
518 	regmap_write(map, MAX17042_MLOCKReg1, MODEL_UNLOCK1);
519 	regmap_write(map, MAX17042_MLOCKReg2, MODEL_UNLOCK2);
520 }
521 
522 static inline void max10742_lock_model(struct max17042_chip *chip)
523 {
524 	struct regmap *map = chip->regmap;
525 
526 	regmap_write(map, MAX17042_MLOCKReg1, MODEL_LOCK1);
527 	regmap_write(map, MAX17042_MLOCKReg2, MODEL_LOCK2);
528 }
529 
530 static inline void max17042_write_model_data(struct max17042_chip *chip,
531 					u8 addr, int size)
532 {
533 	struct regmap *map = chip->regmap;
534 	int i;
535 
536 	for (i = 0; i < size; i++)
537 		regmap_write(map, addr + i,
538 			chip->pdata->config_data->cell_char_tbl[i]);
539 }
540 
541 static inline void max17042_read_model_data(struct max17042_chip *chip,
542 					u8 addr, u16 *data, int size)
543 {
544 	struct regmap *map = chip->regmap;
545 	int i;
546 	u32 tmp;
547 
548 	for (i = 0; i < size; i++) {
549 		regmap_read(map, addr + i, &tmp);
550 		data[i] = (u16)tmp;
551 	}
552 }
553 
554 static inline int max17042_model_data_compare(struct max17042_chip *chip,
555 					u16 *data1, u16 *data2, int size)
556 {
557 	int i;
558 
559 	if (memcmp(data1, data2, size)) {
560 		dev_err(&chip->client->dev, "%s compare failed\n", __func__);
561 		for (i = 0; i < size; i++)
562 			dev_info(&chip->client->dev, "0x%x, 0x%x",
563 				data1[i], data2[i]);
564 		dev_info(&chip->client->dev, "\n");
565 		return -EINVAL;
566 	}
567 	return 0;
568 }
569 
570 static int max17042_init_model(struct max17042_chip *chip)
571 {
572 	int ret;
573 	int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
574 	u16 *temp_data;
575 
576 	temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
577 	if (!temp_data)
578 		return -ENOMEM;
579 
580 	max10742_unlock_model(chip);
581 	max17042_write_model_data(chip, MAX17042_MODELChrTbl,
582 				table_size);
583 	max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
584 				table_size);
585 
586 	ret = max17042_model_data_compare(
587 		chip,
588 		chip->pdata->config_data->cell_char_tbl,
589 		temp_data,
590 		table_size);
591 
592 	max10742_lock_model(chip);
593 	kfree(temp_data);
594 
595 	return ret;
596 }
597 
598 static int max17042_verify_model_lock(struct max17042_chip *chip)
599 {
600 	int i;
601 	int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
602 	u16 *temp_data;
603 	int ret = 0;
604 
605 	temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
606 	if (!temp_data)
607 		return -ENOMEM;
608 
609 	max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
610 				table_size);
611 	for (i = 0; i < table_size; i++)
612 		if (temp_data[i])
613 			ret = -EINVAL;
614 
615 	kfree(temp_data);
616 	return ret;
617 }
618 
619 static void max17042_write_config_regs(struct max17042_chip *chip)
620 {
621 	struct max17042_config_data *config = chip->pdata->config_data;
622 	struct regmap *map = chip->regmap;
623 
624 	regmap_write(map, MAX17042_CONFIG, config->config);
625 	regmap_write(map, MAX17042_LearnCFG, config->learn_cfg);
626 	regmap_write(map, MAX17042_FilterCFG,
627 			config->filter_cfg);
628 	regmap_write(map, MAX17042_RelaxCFG, config->relax_cfg);
629 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17047 ||
630 			chip->chip_type == MAXIM_DEVICE_TYPE_MAX17050)
631 		regmap_write(map, MAX17047_FullSOCThr,
632 						config->full_soc_thresh);
633 }
634 
635 static void  max17042_write_custom_regs(struct max17042_chip *chip)
636 {
637 	struct max17042_config_data *config = chip->pdata->config_data;
638 	struct regmap *map = chip->regmap;
639 
640 	max17042_write_verify_reg(map, MAX17042_RCOMP0, config->rcomp0);
641 	max17042_write_verify_reg(map, MAX17042_TempCo,	config->tcompc0);
642 	max17042_write_verify_reg(map, MAX17042_ICHGTerm, config->ichgt_term);
643 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042) {
644 		regmap_write(map, MAX17042_EmptyTempCo,	config->empty_tempco);
645 		max17042_write_verify_reg(map, MAX17042_K_empty0,
646 					config->kempty0);
647 	} else {
648 		max17042_write_verify_reg(map, MAX17047_QRTbl00,
649 						config->qrtbl00);
650 		max17042_write_verify_reg(map, MAX17047_QRTbl10,
651 						config->qrtbl10);
652 		max17042_write_verify_reg(map, MAX17047_QRTbl20,
653 						config->qrtbl20);
654 		max17042_write_verify_reg(map, MAX17047_QRTbl30,
655 						config->qrtbl30);
656 	}
657 }
658 
659 static void max17042_update_capacity_regs(struct max17042_chip *chip)
660 {
661 	struct max17042_config_data *config = chip->pdata->config_data;
662 	struct regmap *map = chip->regmap;
663 
664 	max17042_write_verify_reg(map, MAX17042_FullCAP,
665 				config->fullcap);
666 	regmap_write(map, MAX17042_DesignCap, config->design_cap);
667 	max17042_write_verify_reg(map, MAX17042_FullCAPNom,
668 				config->fullcapnom);
669 }
670 
671 static void max17042_reset_vfsoc0_reg(struct max17042_chip *chip)
672 {
673 	unsigned int vfSoc;
674 	struct regmap *map = chip->regmap;
675 
676 	regmap_read(map, MAX17042_VFSOC, &vfSoc);
677 	regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_UNLOCK);
678 	max17042_write_verify_reg(map, MAX17042_VFSOC0, vfSoc);
679 	regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_LOCK);
680 }
681 
682 static void max17042_load_new_capacity_params(struct max17042_chip *chip)
683 {
684 	u32 full_cap0, rep_cap, dq_acc, vfSoc;
685 	u32 rem_cap;
686 
687 	struct max17042_config_data *config = chip->pdata->config_data;
688 	struct regmap *map = chip->regmap;
689 
690 	regmap_read(map, MAX17042_FullCAP0, &full_cap0);
691 	regmap_read(map, MAX17042_VFSOC, &vfSoc);
692 
693 	/* fg_vfSoc needs to shifted by 8 bits to get the
694 	 * perc in 1% accuracy, to get the right rem_cap multiply
695 	 * full_cap0, fg_vfSoc and devide by 100
696 	 */
697 	rem_cap = ((vfSoc >> 8) * full_cap0) / 100;
698 	max17042_write_verify_reg(map, MAX17042_RemCap, rem_cap);
699 
700 	rep_cap = rem_cap;
701 	max17042_write_verify_reg(map, MAX17042_RepCap, rep_cap);
702 
703 	/* Write dQ_acc to 200% of Capacity and dP_acc to 200% */
704 	dq_acc = config->fullcap / dQ_ACC_DIV;
705 	max17042_write_verify_reg(map, MAX17042_dQacc, dq_acc);
706 	max17042_write_verify_reg(map, MAX17042_dPacc, dP_ACC_200);
707 
708 	max17042_write_verify_reg(map, MAX17042_FullCAP,
709 			config->fullcap);
710 	regmap_write(map, MAX17042_DesignCap,
711 			config->design_cap);
712 	max17042_write_verify_reg(map, MAX17042_FullCAPNom,
713 			config->fullcapnom);
714 	/* Update SOC register with new SOC */
715 	regmap_write(map, MAX17042_RepSOC, vfSoc);
716 }
717 
718 /*
719  * Block write all the override values coming from platform data.
720  * This function MUST be called before the POR initialization proceedure
721  * specified by maxim.
722  */
723 static inline void max17042_override_por_values(struct max17042_chip *chip)
724 {
725 	struct regmap *map = chip->regmap;
726 	struct max17042_config_data *config = chip->pdata->config_data;
727 
728 	max17042_override_por(map, MAX17042_TGAIN, config->tgain);
729 	max17042_override_por(map, MAx17042_TOFF, config->toff);
730 	max17042_override_por(map, MAX17042_CGAIN, config->cgain);
731 	max17042_override_por(map, MAX17042_COFF, config->coff);
732 
733 	max17042_override_por(map, MAX17042_VALRT_Th, config->valrt_thresh);
734 	max17042_override_por(map, MAX17042_TALRT_Th, config->talrt_thresh);
735 	max17042_override_por(map, MAX17042_SALRT_Th,
736 						config->soc_alrt_thresh);
737 	max17042_override_por(map, MAX17042_CONFIG, config->config);
738 	max17042_override_por(map, MAX17042_SHDNTIMER, config->shdntimer);
739 
740 	max17042_override_por(map, MAX17042_DesignCap, config->design_cap);
741 	max17042_override_por(map, MAX17042_ICHGTerm, config->ichgt_term);
742 
743 	max17042_override_por(map, MAX17042_AtRate, config->at_rate);
744 	max17042_override_por(map, MAX17042_LearnCFG, config->learn_cfg);
745 	max17042_override_por(map, MAX17042_FilterCFG, config->filter_cfg);
746 	max17042_override_por(map, MAX17042_RelaxCFG, config->relax_cfg);
747 	max17042_override_por(map, MAX17042_MiscCFG, config->misc_cfg);
748 	max17042_override_por(map, MAX17042_MaskSOC, config->masksoc);
749 
750 	max17042_override_por(map, MAX17042_FullCAP, config->fullcap);
751 	max17042_override_por(map, MAX17042_FullCAPNom, config->fullcapnom);
752 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
753 		max17042_override_por(map, MAX17042_SOC_empty,
754 						config->socempty);
755 	max17042_override_por(map, MAX17042_LAvg_empty, config->lavg_empty);
756 	max17042_override_por(map, MAX17042_dQacc, config->dqacc);
757 	max17042_override_por(map, MAX17042_dPacc, config->dpacc);
758 
759 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
760 		max17042_override_por(map, MAX17042_V_empty, config->vempty);
761 	else
762 		max17042_override_por(map, MAX17047_V_empty, config->vempty);
763 	max17042_override_por(map, MAX17042_TempNom, config->temp_nom);
764 	max17042_override_por(map, MAX17042_TempLim, config->temp_lim);
765 	max17042_override_por(map, MAX17042_FCTC, config->fctc);
766 	max17042_override_por(map, MAX17042_RCOMP0, config->rcomp0);
767 	max17042_override_por(map, MAX17042_TempCo, config->tcompc0);
768 	if (chip->chip_type) {
769 		max17042_override_por(map, MAX17042_EmptyTempCo,
770 						config->empty_tempco);
771 		max17042_override_por(map, MAX17042_K_empty0,
772 						config->kempty0);
773 	}
774 }
775 
776 static int max17042_init_chip(struct max17042_chip *chip)
777 {
778 	struct regmap *map = chip->regmap;
779 	int ret;
780 
781 	max17042_override_por_values(chip);
782 	/* After Power up, the MAX17042 requires 500mS in order
783 	 * to perform signal debouncing and initial SOC reporting
784 	 */
785 	msleep(500);
786 
787 	/* Initialize configaration */
788 	max17042_write_config_regs(chip);
789 
790 	/* write cell characterization data */
791 	ret = max17042_init_model(chip);
792 	if (ret) {
793 		dev_err(&chip->client->dev, "%s init failed\n",
794 			__func__);
795 		return -EIO;
796 	}
797 
798 	ret = max17042_verify_model_lock(chip);
799 	if (ret) {
800 		dev_err(&chip->client->dev, "%s lock verify failed\n",
801 			__func__);
802 		return -EIO;
803 	}
804 	/* write custom parameters */
805 	max17042_write_custom_regs(chip);
806 
807 	/* update capacity params */
808 	max17042_update_capacity_regs(chip);
809 
810 	/* delay must be atleast 350mS to allow VFSOC
811 	 * to be calculated from the new configuration
812 	 */
813 	msleep(350);
814 
815 	/* reset vfsoc0 reg */
816 	max17042_reset_vfsoc0_reg(chip);
817 
818 	/* load new capacity params */
819 	max17042_load_new_capacity_params(chip);
820 
821 	/* Init complete, Clear the POR bit */
822 	regmap_update_bits(map, MAX17042_STATUS, STATUS_POR_BIT, 0x0);
823 	return 0;
824 }
825 
826 static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
827 {
828 	struct regmap *map = chip->regmap;
829 	u32 soc, soc_tr;
830 
831 	/* program interrupt thesholds such that we should
832 	 * get interrupt for every 'off' perc change in the soc
833 	 */
834 	regmap_read(map, MAX17042_RepSOC, &soc);
835 	soc >>= 8;
836 	soc_tr = (soc + off) << 8;
837 	soc_tr |= (soc - off);
838 	regmap_write(map, MAX17042_SALRT_Th, soc_tr);
839 }
840 
841 static irqreturn_t max17042_thread_handler(int id, void *dev)
842 {
843 	struct max17042_chip *chip = dev;
844 	u32 val;
845 
846 	regmap_read(chip->regmap, MAX17042_STATUS, &val);
847 	if ((val & STATUS_INTR_SOCMIN_BIT) ||
848 		(val & STATUS_INTR_SOCMAX_BIT)) {
849 		dev_info(&chip->client->dev, "SOC threshold INTR\n");
850 		max17042_set_soc_threshold(chip, 1);
851 	}
852 
853 	power_supply_changed(chip->battery);
854 	return IRQ_HANDLED;
855 }
856 
857 static void max17042_init_worker(struct work_struct *work)
858 {
859 	struct max17042_chip *chip = container_of(work,
860 				struct max17042_chip, work);
861 	int ret;
862 
863 	/* Initialize registers according to values from the platform data */
864 	if (chip->pdata->enable_por_init && chip->pdata->config_data) {
865 		ret = max17042_init_chip(chip);
866 		if (ret)
867 			return;
868 	}
869 
870 	chip->init_complete = 1;
871 }
872 
873 #ifdef CONFIG_OF
874 static struct max17042_platform_data *
875 max17042_get_of_pdata(struct max17042_chip *chip)
876 {
877 	struct device *dev = &chip->client->dev;
878 	struct device_node *np = dev->of_node;
879 	u32 prop;
880 	struct max17042_platform_data *pdata;
881 
882 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
883 	if (!pdata)
884 		return NULL;
885 
886 	/*
887 	 * Require current sense resistor value to be specified for
888 	 * current-sense functionality to be enabled at all.
889 	 */
890 	if (of_property_read_u32(np, "maxim,rsns-microohm", &prop) == 0) {
891 		pdata->r_sns = prop;
892 		pdata->enable_current_sense = true;
893 	}
894 
895 	if (of_property_read_s32(np, "maxim,cold-temp", &pdata->temp_min))
896 		pdata->temp_min = INT_MIN;
897 	if (of_property_read_s32(np, "maxim,over-heat-temp", &pdata->temp_max))
898 		pdata->temp_max = INT_MAX;
899 	if (of_property_read_s32(np, "maxim,dead-volt", &pdata->vmin))
900 		pdata->vmin = INT_MIN;
901 	if (of_property_read_s32(np, "maxim,over-volt", &pdata->vmax))
902 		pdata->vmax = INT_MAX;
903 
904 	return pdata;
905 }
906 #endif
907 
908 static struct max17042_reg_data max17047_default_pdata_init_regs[] = {
909 	/*
910 	 * Some firmwares do not set FullSOCThr, Enable End-of-Charge Detection
911 	 * when the voltage FG reports 95%, as recommended in the datasheet.
912 	 */
913 	{ MAX17047_FullSOCThr, MAX17042_BATTERY_FULL << 8 },
914 };
915 
916 static struct max17042_platform_data *
917 max17042_get_default_pdata(struct max17042_chip *chip)
918 {
919 	struct device *dev = &chip->client->dev;
920 	struct max17042_platform_data *pdata;
921 	int ret, misc_cfg;
922 
923 	/*
924 	 * The MAX17047 gets used on x86 where we might not have pdata, assume
925 	 * the firmware will already have initialized the fuel-gauge and provide
926 	 * default values for the non init bits to make things work.
927 	 */
928 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
929 	if (!pdata)
930 		return pdata;
931 
932 	if (chip->chip_type != MAXIM_DEVICE_TYPE_MAX17042) {
933 		pdata->init_data = max17047_default_pdata_init_regs;
934 		pdata->num_init_data =
935 			ARRAY_SIZE(max17047_default_pdata_init_regs);
936 	}
937 
938 	ret = regmap_read(chip->regmap, MAX17042_MiscCFG, &misc_cfg);
939 	if (ret < 0)
940 		return NULL;
941 
942 	/* If bits 0-1 are set to 3 then only Voltage readings are used */
943 	if ((misc_cfg & 0x3) == 0x3)
944 		pdata->enable_current_sense = false;
945 	else
946 		pdata->enable_current_sense = true;
947 
948 	pdata->vmin = MAX17042_DEFAULT_VMIN;
949 	pdata->vmax = MAX17042_DEFAULT_VMAX;
950 	pdata->temp_min = MAX17042_DEFAULT_TEMP_MIN;
951 	pdata->temp_max = MAX17042_DEFAULT_TEMP_MAX;
952 
953 	return pdata;
954 }
955 
956 static struct max17042_platform_data *
957 max17042_get_pdata(struct max17042_chip *chip)
958 {
959 	struct device *dev = &chip->client->dev;
960 
961 #ifdef CONFIG_OF
962 	if (dev->of_node)
963 		return max17042_get_of_pdata(chip);
964 #endif
965 	if (dev->platform_data)
966 		return dev->platform_data;
967 
968 	return max17042_get_default_pdata(chip);
969 }
970 
971 static const struct regmap_config max17042_regmap_config = {
972 	.reg_bits = 8,
973 	.val_bits = 16,
974 	.val_format_endian = REGMAP_ENDIAN_NATIVE,
975 };
976 
977 static const struct power_supply_desc max17042_psy_desc = {
978 	.name		= "max170xx_battery",
979 	.type		= POWER_SUPPLY_TYPE_BATTERY,
980 	.get_property	= max17042_get_property,
981 	.set_property	= max17042_set_property,
982 	.property_is_writeable	= max17042_property_is_writeable,
983 	.external_power_changed	= max17042_external_power_changed,
984 	.properties	= max17042_battery_props,
985 	.num_properties	= ARRAY_SIZE(max17042_battery_props),
986 };
987 
988 static const struct power_supply_desc max17042_no_current_sense_psy_desc = {
989 	.name		= "max170xx_battery",
990 	.type		= POWER_SUPPLY_TYPE_BATTERY,
991 	.get_property	= max17042_get_property,
992 	.set_property	= max17042_set_property,
993 	.property_is_writeable	= max17042_property_is_writeable,
994 	.properties	= max17042_battery_props,
995 	.num_properties	= ARRAY_SIZE(max17042_battery_props) - 2,
996 };
997 
998 static void max17042_stop_work(void *data)
999 {
1000 	struct max17042_chip *chip = data;
1001 
1002 	cancel_work_sync(&chip->work);
1003 }
1004 
1005 static int max17042_probe(struct i2c_client *client,
1006 			const struct i2c_device_id *id)
1007 {
1008 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
1009 	const struct power_supply_desc *max17042_desc = &max17042_psy_desc;
1010 	struct power_supply_config psy_cfg = {};
1011 	const struct acpi_device_id *acpi_id = NULL;
1012 	struct device *dev = &client->dev;
1013 	struct max17042_chip *chip;
1014 	int ret;
1015 	int i;
1016 	u32 val;
1017 
1018 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
1019 		return -EIO;
1020 
1021 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
1022 	if (!chip)
1023 		return -ENOMEM;
1024 
1025 	chip->client = client;
1026 	if (id) {
1027 		chip->chip_type = id->driver_data;
1028 	} else {
1029 		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
1030 		if (!acpi_id)
1031 			return -ENODEV;
1032 
1033 		chip->chip_type = acpi_id->driver_data;
1034 	}
1035 	chip->regmap = devm_regmap_init_i2c(client, &max17042_regmap_config);
1036 	if (IS_ERR(chip->regmap)) {
1037 		dev_err(&client->dev, "Failed to initialize regmap\n");
1038 		return -EINVAL;
1039 	}
1040 
1041 	chip->pdata = max17042_get_pdata(chip);
1042 	if (!chip->pdata) {
1043 		dev_err(&client->dev, "no platform data provided\n");
1044 		return -EINVAL;
1045 	}
1046 
1047 	i2c_set_clientdata(client, chip);
1048 	psy_cfg.drv_data = chip;
1049 	psy_cfg.of_node = dev->of_node;
1050 
1051 	/* When current is not measured,
1052 	 * CURRENT_NOW and CURRENT_AVG properties should be invisible. */
1053 	if (!chip->pdata->enable_current_sense)
1054 		max17042_desc = &max17042_no_current_sense_psy_desc;
1055 
1056 	if (chip->pdata->r_sns == 0)
1057 		chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR;
1058 
1059 	if (chip->pdata->init_data)
1060 		for (i = 0; i < chip->pdata->num_init_data; i++)
1061 			regmap_write(chip->regmap,
1062 					chip->pdata->init_data[i].addr,
1063 					chip->pdata->init_data[i].data);
1064 
1065 	if (!chip->pdata->enable_current_sense) {
1066 		regmap_write(chip->regmap, MAX17042_CGAIN, 0x0000);
1067 		regmap_write(chip->regmap, MAX17042_MiscCFG, 0x0003);
1068 		regmap_write(chip->regmap, MAX17042_LearnCFG, 0x0007);
1069 	}
1070 
1071 	chip->battery = devm_power_supply_register(&client->dev, max17042_desc,
1072 						   &psy_cfg);
1073 	if (IS_ERR(chip->battery)) {
1074 		dev_err(&client->dev, "failed: power supply register\n");
1075 		return PTR_ERR(chip->battery);
1076 	}
1077 
1078 	if (client->irq) {
1079 		unsigned int flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
1080 
1081 		/*
1082 		 * On ACPI systems the IRQ may be handled by ACPI-event code,
1083 		 * so we need to share (if the ACPI code is willing to share).
1084 		 */
1085 		if (acpi_id)
1086 			flags |= IRQF_SHARED | IRQF_PROBE_SHARED;
1087 
1088 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1089 						NULL,
1090 						max17042_thread_handler, flags,
1091 						chip->battery->desc->name,
1092 						chip);
1093 		if (!ret) {
1094 			regmap_update_bits(chip->regmap, MAX17042_CONFIG,
1095 					CONFIG_ALRT_BIT_ENBL,
1096 					CONFIG_ALRT_BIT_ENBL);
1097 			max17042_set_soc_threshold(chip, 1);
1098 		} else {
1099 			client->irq = 0;
1100 			if (ret != -EBUSY)
1101 				dev_err(&client->dev, "Failed to get IRQ\n");
1102 		}
1103 	}
1104 	/* Not able to update the charge threshold when exceeded? -> disable */
1105 	if (!client->irq)
1106 		regmap_write(chip->regmap, MAX17042_SALRT_Th, 0xff00);
1107 
1108 	regmap_read(chip->regmap, MAX17042_STATUS, &val);
1109 	if (val & STATUS_POR_BIT) {
1110 		INIT_WORK(&chip->work, max17042_init_worker);
1111 		ret = devm_add_action(&client->dev, max17042_stop_work, chip);
1112 		if (ret)
1113 			return ret;
1114 		schedule_work(&chip->work);
1115 	} else {
1116 		chip->init_complete = 1;
1117 	}
1118 
1119 	return 0;
1120 }
1121 
1122 #ifdef CONFIG_PM_SLEEP
1123 static int max17042_suspend(struct device *dev)
1124 {
1125 	struct max17042_chip *chip = dev_get_drvdata(dev);
1126 
1127 	/*
1128 	 * disable the irq and enable irq_wake
1129 	 * capability to the interrupt line.
1130 	 */
1131 	if (chip->client->irq) {
1132 		disable_irq(chip->client->irq);
1133 		enable_irq_wake(chip->client->irq);
1134 	}
1135 
1136 	return 0;
1137 }
1138 
1139 static int max17042_resume(struct device *dev)
1140 {
1141 	struct max17042_chip *chip = dev_get_drvdata(dev);
1142 
1143 	if (chip->client->irq) {
1144 		disable_irq_wake(chip->client->irq);
1145 		enable_irq(chip->client->irq);
1146 		/* re-program the SOC thresholds to 1% change */
1147 		max17042_set_soc_threshold(chip, 1);
1148 	}
1149 
1150 	return 0;
1151 }
1152 #endif
1153 
1154 static SIMPLE_DEV_PM_OPS(max17042_pm_ops, max17042_suspend,
1155 			max17042_resume);
1156 
1157 #ifdef CONFIG_ACPI
1158 static const struct acpi_device_id max17042_acpi_match[] = {
1159 	{ "MAX17047", MAXIM_DEVICE_TYPE_MAX17047 },
1160 	{ }
1161 };
1162 MODULE_DEVICE_TABLE(acpi, max17042_acpi_match);
1163 #endif
1164 
1165 #ifdef CONFIG_OF
1166 static const struct of_device_id max17042_dt_match[] = {
1167 	{ .compatible = "maxim,max17042" },
1168 	{ .compatible = "maxim,max17047" },
1169 	{ .compatible = "maxim,max17050" },
1170 	{ },
1171 };
1172 MODULE_DEVICE_TABLE(of, max17042_dt_match);
1173 #endif
1174 
1175 static const struct i2c_device_id max17042_id[] = {
1176 	{ "max17042", MAXIM_DEVICE_TYPE_MAX17042 },
1177 	{ "max17047", MAXIM_DEVICE_TYPE_MAX17047 },
1178 	{ "max17050", MAXIM_DEVICE_TYPE_MAX17050 },
1179 	{ }
1180 };
1181 MODULE_DEVICE_TABLE(i2c, max17042_id);
1182 
1183 static struct i2c_driver max17042_i2c_driver = {
1184 	.driver	= {
1185 		.name	= "max17042",
1186 		.acpi_match_table = ACPI_PTR(max17042_acpi_match),
1187 		.of_match_table = of_match_ptr(max17042_dt_match),
1188 		.pm	= &max17042_pm_ops,
1189 	},
1190 	.probe		= max17042_probe,
1191 	.id_table	= max17042_id,
1192 };
1193 module_i2c_driver(max17042_i2c_driver);
1194 
1195 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1196 MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
1197 MODULE_LICENSE("GPL");
1198