1 /*
2  * Fuel gauge driver for Maxim 17042 / 8966 / 8997
3  *  Note that Maxim 8966 and 8997 are mfd and this is its subdevice.
4  *
5  * Copyright (C) 2011 Samsung Electronics
6  * MyungJoo Ham <myungjoo.ham@samsung.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  *
22  * This driver is based on max17040_battery.c
23  */
24 
25 #include <linux/acpi.h>
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/slab.h>
29 #include <linux/i2c.h>
30 #include <linux/delay.h>
31 #include <linux/interrupt.h>
32 #include <linux/pm.h>
33 #include <linux/mod_devicetable.h>
34 #include <linux/power_supply.h>
35 #include <linux/power/max17042_battery.h>
36 #include <linux/of.h>
37 #include <linux/regmap.h>
38 
39 /* Status register bits */
40 #define STATUS_POR_BIT         (1 << 1)
41 #define STATUS_BST_BIT         (1 << 3)
42 #define STATUS_VMN_BIT         (1 << 8)
43 #define STATUS_TMN_BIT         (1 << 9)
44 #define STATUS_SMN_BIT         (1 << 10)
45 #define STATUS_BI_BIT          (1 << 11)
46 #define STATUS_VMX_BIT         (1 << 12)
47 #define STATUS_TMX_BIT         (1 << 13)
48 #define STATUS_SMX_BIT         (1 << 14)
49 #define STATUS_BR_BIT          (1 << 15)
50 
51 /* Interrupt mask bits */
52 #define CONFIG_ALRT_BIT_ENBL	(1 << 2)
53 #define STATUS_INTR_SOCMIN_BIT	(1 << 10)
54 #define STATUS_INTR_SOCMAX_BIT	(1 << 14)
55 
56 #define VFSOC0_LOCK		0x0000
57 #define VFSOC0_UNLOCK		0x0080
58 #define MODEL_UNLOCK1	0X0059
59 #define MODEL_UNLOCK2	0X00C4
60 #define MODEL_LOCK1		0X0000
61 #define MODEL_LOCK2		0X0000
62 
63 #define dQ_ACC_DIV	0x4
64 #define dP_ACC_100	0x1900
65 #define dP_ACC_200	0x3200
66 
67 #define MAX17042_VMAX_TOLERANCE		50 /* 50 mV */
68 
69 struct max17042_chip {
70 	struct i2c_client *client;
71 	struct regmap *regmap;
72 	struct power_supply *battery;
73 	enum max170xx_chip_type chip_type;
74 	struct max17042_platform_data *pdata;
75 	struct work_struct work;
76 	int    init_complete;
77 };
78 
79 static enum power_supply_property max17042_battery_props[] = {
80 	POWER_SUPPLY_PROP_STATUS,
81 	POWER_SUPPLY_PROP_PRESENT,
82 	POWER_SUPPLY_PROP_TECHNOLOGY,
83 	POWER_SUPPLY_PROP_CYCLE_COUNT,
84 	POWER_SUPPLY_PROP_VOLTAGE_MAX,
85 	POWER_SUPPLY_PROP_VOLTAGE_MIN,
86 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
87 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
88 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
89 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
90 	POWER_SUPPLY_PROP_CAPACITY,
91 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
92 	POWER_SUPPLY_PROP_CHARGE_FULL,
93 	POWER_SUPPLY_PROP_CHARGE_NOW,
94 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
95 	POWER_SUPPLY_PROP_TEMP,
96 	POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
97 	POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
98 	POWER_SUPPLY_PROP_TEMP_MIN,
99 	POWER_SUPPLY_PROP_TEMP_MAX,
100 	POWER_SUPPLY_PROP_HEALTH,
101 	POWER_SUPPLY_PROP_SCOPE,
102 	POWER_SUPPLY_PROP_CURRENT_NOW,
103 	POWER_SUPPLY_PROP_CURRENT_AVG,
104 };
105 
106 static int max17042_get_temperature(struct max17042_chip *chip, int *temp)
107 {
108 	int ret;
109 	u32 data;
110 	struct regmap *map = chip->regmap;
111 
112 	ret = regmap_read(map, MAX17042_TEMP, &data);
113 	if (ret < 0)
114 		return ret;
115 
116 	*temp = sign_extend32(data, 15);
117 	/* The value is converted into deci-centigrade scale */
118 	/* Units of LSB = 1 / 256 degree Celsius */
119 	*temp = *temp * 10 / 256;
120 	return 0;
121 }
122 
123 static int max17042_get_status(struct max17042_chip *chip, int *status)
124 {
125 	int ret, charge_full, charge_now;
126 	int avg_current;
127 	u32 data;
128 
129 	ret = power_supply_am_i_supplied(chip->battery);
130 	if (ret < 0) {
131 		*status = POWER_SUPPLY_STATUS_UNKNOWN;
132 		return 0;
133 	}
134 	if (ret == 0) {
135 		*status = POWER_SUPPLY_STATUS_DISCHARGING;
136 		return 0;
137 	}
138 
139 	/*
140 	 * The MAX170xx has builtin end-of-charge detection and will update
141 	 * FullCAP to match RepCap when it detects end of charging.
142 	 *
143 	 * When this cycle the battery gets charged to a higher (calculated)
144 	 * capacity then the previous cycle then FullCAP will get updated
145 	 * contineously once end-of-charge detection kicks in, so allow the
146 	 * 2 to differ a bit.
147 	 */
148 
149 	ret = regmap_read(chip->regmap, MAX17042_FullCAP, &charge_full);
150 	if (ret < 0)
151 		return ret;
152 
153 	ret = regmap_read(chip->regmap, MAX17042_RepCap, &charge_now);
154 	if (ret < 0)
155 		return ret;
156 
157 	if ((charge_full - charge_now) <= MAX17042_FULL_THRESHOLD) {
158 		*status = POWER_SUPPLY_STATUS_FULL;
159 		return 0;
160 	}
161 
162 	/*
163 	 * Even though we are supplied, we may still be discharging if the
164 	 * supply is e.g. only delivering 5V 0.5A. Check current if available.
165 	 */
166 	if (!chip->pdata->enable_current_sense) {
167 		*status = POWER_SUPPLY_STATUS_CHARGING;
168 		return 0;
169 	}
170 
171 	ret = regmap_read(chip->regmap, MAX17042_AvgCurrent, &data);
172 	if (ret < 0)
173 		return ret;
174 
175 	avg_current = sign_extend32(data, 15);
176 	avg_current *= 1562500 / chip->pdata->r_sns;
177 
178 	if (avg_current > 0)
179 		*status = POWER_SUPPLY_STATUS_CHARGING;
180 	else
181 		*status = POWER_SUPPLY_STATUS_DISCHARGING;
182 
183 	return 0;
184 }
185 
186 static int max17042_get_battery_health(struct max17042_chip *chip, int *health)
187 {
188 	int temp, vavg, vbatt, ret;
189 	u32 val;
190 
191 	ret = regmap_read(chip->regmap, MAX17042_AvgVCELL, &val);
192 	if (ret < 0)
193 		goto health_error;
194 
195 	/* bits [0-3] unused */
196 	vavg = val * 625 / 8;
197 	/* Convert to millivolts */
198 	vavg /= 1000;
199 
200 	ret = regmap_read(chip->regmap, MAX17042_VCELL, &val);
201 	if (ret < 0)
202 		goto health_error;
203 
204 	/* bits [0-3] unused */
205 	vbatt = val * 625 / 8;
206 	/* Convert to millivolts */
207 	vbatt /= 1000;
208 
209 	if (vavg < chip->pdata->vmin) {
210 		*health = POWER_SUPPLY_HEALTH_DEAD;
211 		goto out;
212 	}
213 
214 	if (vbatt > chip->pdata->vmax + MAX17042_VMAX_TOLERANCE) {
215 		*health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
216 		goto out;
217 	}
218 
219 	ret = max17042_get_temperature(chip, &temp);
220 	if (ret < 0)
221 		goto health_error;
222 
223 	if (temp < chip->pdata->temp_min) {
224 		*health = POWER_SUPPLY_HEALTH_COLD;
225 		goto out;
226 	}
227 
228 	if (temp > chip->pdata->temp_max) {
229 		*health = POWER_SUPPLY_HEALTH_OVERHEAT;
230 		goto out;
231 	}
232 
233 	*health = POWER_SUPPLY_HEALTH_GOOD;
234 
235 out:
236 	return 0;
237 
238 health_error:
239 	return ret;
240 }
241 
242 static int max17042_get_property(struct power_supply *psy,
243 			    enum power_supply_property psp,
244 			    union power_supply_propval *val)
245 {
246 	struct max17042_chip *chip = power_supply_get_drvdata(psy);
247 	struct regmap *map = chip->regmap;
248 	int ret;
249 	u32 data;
250 	u64 data64;
251 
252 	if (!chip->init_complete)
253 		return -EAGAIN;
254 
255 	switch (psp) {
256 	case POWER_SUPPLY_PROP_STATUS:
257 		ret = max17042_get_status(chip, &val->intval);
258 		if (ret < 0)
259 			return ret;
260 		break;
261 	case POWER_SUPPLY_PROP_PRESENT:
262 		ret = regmap_read(map, MAX17042_STATUS, &data);
263 		if (ret < 0)
264 			return ret;
265 
266 		if (data & MAX17042_STATUS_BattAbsent)
267 			val->intval = 0;
268 		else
269 			val->intval = 1;
270 		break;
271 	case POWER_SUPPLY_PROP_TECHNOLOGY:
272 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
273 		break;
274 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
275 		ret = regmap_read(map, MAX17042_Cycles, &data);
276 		if (ret < 0)
277 			return ret;
278 
279 		val->intval = data;
280 		break;
281 	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
282 		ret = regmap_read(map, MAX17042_MinMaxVolt, &data);
283 		if (ret < 0)
284 			return ret;
285 
286 		val->intval = data >> 8;
287 		val->intval *= 20000; /* Units of LSB = 20mV */
288 		break;
289 	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
290 		ret = regmap_read(map, MAX17042_MinMaxVolt, &data);
291 		if (ret < 0)
292 			return ret;
293 
294 		val->intval = (data & 0xff) * 20000; /* Units of 20mV */
295 		break;
296 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
297 		if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
298 			ret = regmap_read(map, MAX17042_V_empty, &data);
299 		else
300 			ret = regmap_read(map, MAX17047_V_empty, &data);
301 		if (ret < 0)
302 			return ret;
303 
304 		val->intval = data >> 7;
305 		val->intval *= 10000; /* Units of LSB = 10mV */
306 		break;
307 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
308 		ret = regmap_read(map, MAX17042_VCELL, &data);
309 		if (ret < 0)
310 			return ret;
311 
312 		val->intval = data * 625 / 8;
313 		break;
314 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
315 		ret = regmap_read(map, MAX17042_AvgVCELL, &data);
316 		if (ret < 0)
317 			return ret;
318 
319 		val->intval = data * 625 / 8;
320 		break;
321 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
322 		ret = regmap_read(map, MAX17042_OCVInternal, &data);
323 		if (ret < 0)
324 			return ret;
325 
326 		val->intval = data * 625 / 8;
327 		break;
328 	case POWER_SUPPLY_PROP_CAPACITY:
329 		ret = regmap_read(map, MAX17042_RepSOC, &data);
330 		if (ret < 0)
331 			return ret;
332 
333 		val->intval = data >> 8;
334 		break;
335 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
336 		ret = regmap_read(map, MAX17042_DesignCap, &data);
337 		if (ret < 0)
338 			return ret;
339 
340 		data64 = data * 5000000ll;
341 		do_div(data64, chip->pdata->r_sns);
342 		val->intval = data64;
343 		break;
344 	case POWER_SUPPLY_PROP_CHARGE_FULL:
345 		ret = regmap_read(map, MAX17042_FullCAP, &data);
346 		if (ret < 0)
347 			return ret;
348 
349 		data64 = data * 5000000ll;
350 		do_div(data64, chip->pdata->r_sns);
351 		val->intval = data64;
352 		break;
353 	case POWER_SUPPLY_PROP_CHARGE_NOW:
354 		ret = regmap_read(map, MAX17042_RepCap, &data);
355 		if (ret < 0)
356 			return ret;
357 
358 		data64 = data * 5000000ll;
359 		do_div(data64, chip->pdata->r_sns);
360 		val->intval = data64;
361 		break;
362 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
363 		ret = regmap_read(map, MAX17042_QH, &data);
364 		if (ret < 0)
365 			return ret;
366 
367 		val->intval = data * 1000 / 2;
368 		break;
369 	case POWER_SUPPLY_PROP_TEMP:
370 		ret = max17042_get_temperature(chip, &val->intval);
371 		if (ret < 0)
372 			return ret;
373 		break;
374 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
375 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
376 		if (ret < 0)
377 			return ret;
378 		/* LSB is Alert Minimum. In deci-centigrade */
379 		val->intval = sign_extend32(data & 0xff, 7) * 10;
380 		break;
381 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
382 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
383 		if (ret < 0)
384 			return ret;
385 		/* MSB is Alert Maximum. In deci-centigrade */
386 		val->intval = sign_extend32(data >> 8, 7) * 10;
387 		break;
388 	case POWER_SUPPLY_PROP_TEMP_MIN:
389 		val->intval = chip->pdata->temp_min;
390 		break;
391 	case POWER_SUPPLY_PROP_TEMP_MAX:
392 		val->intval = chip->pdata->temp_max;
393 		break;
394 	case POWER_SUPPLY_PROP_HEALTH:
395 		ret = max17042_get_battery_health(chip, &val->intval);
396 		if (ret < 0)
397 			return ret;
398 		break;
399 	case POWER_SUPPLY_PROP_SCOPE:
400 		val->intval = POWER_SUPPLY_SCOPE_SYSTEM;
401 		break;
402 	case POWER_SUPPLY_PROP_CURRENT_NOW:
403 		if (chip->pdata->enable_current_sense) {
404 			ret = regmap_read(map, MAX17042_Current, &data);
405 			if (ret < 0)
406 				return ret;
407 
408 			val->intval = sign_extend32(data, 15);
409 			val->intval *= 1562500 / chip->pdata->r_sns;
410 		} else {
411 			return -EINVAL;
412 		}
413 		break;
414 	case POWER_SUPPLY_PROP_CURRENT_AVG:
415 		if (chip->pdata->enable_current_sense) {
416 			ret = regmap_read(map, MAX17042_AvgCurrent, &data);
417 			if (ret < 0)
418 				return ret;
419 
420 			val->intval = sign_extend32(data, 15);
421 			val->intval *= 1562500 / chip->pdata->r_sns;
422 		} else {
423 			return -EINVAL;
424 		}
425 		break;
426 	default:
427 		return -EINVAL;
428 	}
429 	return 0;
430 }
431 
432 static int max17042_set_property(struct power_supply *psy,
433 			    enum power_supply_property psp,
434 			    const union power_supply_propval *val)
435 {
436 	struct max17042_chip *chip = power_supply_get_drvdata(psy);
437 	struct regmap *map = chip->regmap;
438 	int ret = 0;
439 	u32 data;
440 	int8_t temp;
441 
442 	switch (psp) {
443 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
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 min < max */
451 		if (temp >= (int8_t)(data >> 8))
452 			temp = (int8_t)(data >> 8) - 1;
453 		/* Write both MAX and MIN ALERT */
454 		data = (data & 0xff00) + temp;
455 		ret = regmap_write(map, MAX17042_TALRT_Th, data);
456 		break;
457 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
458 		ret = regmap_read(map, MAX17042_TALRT_Th, &data);
459 		if (ret < 0)
460 			return ret;
461 
462 		/* Input in Deci-Centigrade, convert to centigrade */
463 		temp = val->intval / 10;
464 		/* force max > min */
465 		if (temp <= (int8_t)(data & 0xff))
466 			temp = (int8_t)(data & 0xff) + 1;
467 		/* Write both MAX and MIN ALERT */
468 		data = (data & 0xff) + (temp << 8);
469 		ret = regmap_write(map, MAX17042_TALRT_Th, data);
470 		break;
471 	default:
472 		ret = -EINVAL;
473 	}
474 
475 	return ret;
476 }
477 
478 static int max17042_property_is_writeable(struct power_supply *psy,
479 		enum power_supply_property psp)
480 {
481 	int ret;
482 
483 	switch (psp) {
484 	case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
485 	case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
486 		ret = 1;
487 		break;
488 	default:
489 		ret = 0;
490 	}
491 
492 	return ret;
493 }
494 
495 static void max17042_external_power_changed(struct power_supply *psy)
496 {
497 	power_supply_changed(psy);
498 }
499 
500 static int max17042_write_verify_reg(struct regmap *map, u8 reg, u32 value)
501 {
502 	int retries = 8;
503 	int ret;
504 	u32 read_value;
505 
506 	do {
507 		ret = regmap_write(map, reg, value);
508 		regmap_read(map, reg, &read_value);
509 		if (read_value != value) {
510 			ret = -EIO;
511 			retries--;
512 		}
513 	} while (retries && read_value != value);
514 
515 	if (ret < 0)
516 		pr_err("%s: err %d\n", __func__, ret);
517 
518 	return ret;
519 }
520 
521 static inline void max17042_override_por(struct regmap *map,
522 					 u8 reg, u16 value)
523 {
524 	if (value)
525 		regmap_write(map, reg, value);
526 }
527 
528 static inline void max10742_unlock_model(struct max17042_chip *chip)
529 {
530 	struct regmap *map = chip->regmap;
531 
532 	regmap_write(map, MAX17042_MLOCKReg1, MODEL_UNLOCK1);
533 	regmap_write(map, MAX17042_MLOCKReg2, MODEL_UNLOCK2);
534 }
535 
536 static inline void max10742_lock_model(struct max17042_chip *chip)
537 {
538 	struct regmap *map = chip->regmap;
539 
540 	regmap_write(map, MAX17042_MLOCKReg1, MODEL_LOCK1);
541 	regmap_write(map, MAX17042_MLOCKReg2, MODEL_LOCK2);
542 }
543 
544 static inline void max17042_write_model_data(struct max17042_chip *chip,
545 					u8 addr, int size)
546 {
547 	struct regmap *map = chip->regmap;
548 	int i;
549 
550 	for (i = 0; i < size; i++)
551 		regmap_write(map, addr + i,
552 			chip->pdata->config_data->cell_char_tbl[i]);
553 }
554 
555 static inline void max17042_read_model_data(struct max17042_chip *chip,
556 					u8 addr, u16 *data, int size)
557 {
558 	struct regmap *map = chip->regmap;
559 	int i;
560 	u32 tmp;
561 
562 	for (i = 0; i < size; i++) {
563 		regmap_read(map, addr + i, &tmp);
564 		data[i] = (u16)tmp;
565 	}
566 }
567 
568 static inline int max17042_model_data_compare(struct max17042_chip *chip,
569 					u16 *data1, u16 *data2, int size)
570 {
571 	int i;
572 
573 	if (memcmp(data1, data2, size)) {
574 		dev_err(&chip->client->dev, "%s compare failed\n", __func__);
575 		for (i = 0; i < size; i++)
576 			dev_info(&chip->client->dev, "0x%x, 0x%x",
577 				data1[i], data2[i]);
578 		dev_info(&chip->client->dev, "\n");
579 		return -EINVAL;
580 	}
581 	return 0;
582 }
583 
584 static int max17042_init_model(struct max17042_chip *chip)
585 {
586 	int ret;
587 	int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
588 	u16 *temp_data;
589 
590 	temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
591 	if (!temp_data)
592 		return -ENOMEM;
593 
594 	max10742_unlock_model(chip);
595 	max17042_write_model_data(chip, MAX17042_MODELChrTbl,
596 				table_size);
597 	max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
598 				table_size);
599 
600 	ret = max17042_model_data_compare(
601 		chip,
602 		chip->pdata->config_data->cell_char_tbl,
603 		temp_data,
604 		table_size);
605 
606 	max10742_lock_model(chip);
607 	kfree(temp_data);
608 
609 	return ret;
610 }
611 
612 static int max17042_verify_model_lock(struct max17042_chip *chip)
613 {
614 	int i;
615 	int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
616 	u16 *temp_data;
617 	int ret = 0;
618 
619 	temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
620 	if (!temp_data)
621 		return -ENOMEM;
622 
623 	max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
624 				table_size);
625 	for (i = 0; i < table_size; i++)
626 		if (temp_data[i])
627 			ret = -EINVAL;
628 
629 	kfree(temp_data);
630 	return ret;
631 }
632 
633 static void max17042_write_config_regs(struct max17042_chip *chip)
634 {
635 	struct max17042_config_data *config = chip->pdata->config_data;
636 	struct regmap *map = chip->regmap;
637 
638 	regmap_write(map, MAX17042_CONFIG, config->config);
639 	regmap_write(map, MAX17042_LearnCFG, config->learn_cfg);
640 	regmap_write(map, MAX17042_FilterCFG,
641 			config->filter_cfg);
642 	regmap_write(map, MAX17042_RelaxCFG, config->relax_cfg);
643 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17047 ||
644 			chip->chip_type == MAXIM_DEVICE_TYPE_MAX17050)
645 		regmap_write(map, MAX17047_FullSOCThr,
646 						config->full_soc_thresh);
647 }
648 
649 static void  max17042_write_custom_regs(struct max17042_chip *chip)
650 {
651 	struct max17042_config_data *config = chip->pdata->config_data;
652 	struct regmap *map = chip->regmap;
653 
654 	max17042_write_verify_reg(map, MAX17042_RCOMP0, config->rcomp0);
655 	max17042_write_verify_reg(map, MAX17042_TempCo,	config->tcompc0);
656 	max17042_write_verify_reg(map, MAX17042_ICHGTerm, config->ichgt_term);
657 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042) {
658 		regmap_write(map, MAX17042_EmptyTempCo,	config->empty_tempco);
659 		max17042_write_verify_reg(map, MAX17042_K_empty0,
660 					config->kempty0);
661 	} else {
662 		max17042_write_verify_reg(map, MAX17047_QRTbl00,
663 						config->qrtbl00);
664 		max17042_write_verify_reg(map, MAX17047_QRTbl10,
665 						config->qrtbl10);
666 		max17042_write_verify_reg(map, MAX17047_QRTbl20,
667 						config->qrtbl20);
668 		max17042_write_verify_reg(map, MAX17047_QRTbl30,
669 						config->qrtbl30);
670 	}
671 }
672 
673 static void max17042_update_capacity_regs(struct max17042_chip *chip)
674 {
675 	struct max17042_config_data *config = chip->pdata->config_data;
676 	struct regmap *map = chip->regmap;
677 
678 	max17042_write_verify_reg(map, MAX17042_FullCAP,
679 				config->fullcap);
680 	regmap_write(map, MAX17042_DesignCap, config->design_cap);
681 	max17042_write_verify_reg(map, MAX17042_FullCAPNom,
682 				config->fullcapnom);
683 }
684 
685 static void max17042_reset_vfsoc0_reg(struct max17042_chip *chip)
686 {
687 	unsigned int vfSoc;
688 	struct regmap *map = chip->regmap;
689 
690 	regmap_read(map, MAX17042_VFSOC, &vfSoc);
691 	regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_UNLOCK);
692 	max17042_write_verify_reg(map, MAX17042_VFSOC0, vfSoc);
693 	regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_LOCK);
694 }
695 
696 static void max17042_load_new_capacity_params(struct max17042_chip *chip)
697 {
698 	u32 full_cap0, rep_cap, dq_acc, vfSoc;
699 	u32 rem_cap;
700 
701 	struct max17042_config_data *config = chip->pdata->config_data;
702 	struct regmap *map = chip->regmap;
703 
704 	regmap_read(map, MAX17042_FullCAP0, &full_cap0);
705 	regmap_read(map, MAX17042_VFSOC, &vfSoc);
706 
707 	/* fg_vfSoc needs to shifted by 8 bits to get the
708 	 * perc in 1% accuracy, to get the right rem_cap multiply
709 	 * full_cap0, fg_vfSoc and devide by 100
710 	 */
711 	rem_cap = ((vfSoc >> 8) * full_cap0) / 100;
712 	max17042_write_verify_reg(map, MAX17042_RemCap, rem_cap);
713 
714 	rep_cap = rem_cap;
715 	max17042_write_verify_reg(map, MAX17042_RepCap, rep_cap);
716 
717 	/* Write dQ_acc to 200% of Capacity and dP_acc to 200% */
718 	dq_acc = config->fullcap / dQ_ACC_DIV;
719 	max17042_write_verify_reg(map, MAX17042_dQacc, dq_acc);
720 	max17042_write_verify_reg(map, MAX17042_dPacc, dP_ACC_200);
721 
722 	max17042_write_verify_reg(map, MAX17042_FullCAP,
723 			config->fullcap);
724 	regmap_write(map, MAX17042_DesignCap,
725 			config->design_cap);
726 	max17042_write_verify_reg(map, MAX17042_FullCAPNom,
727 			config->fullcapnom);
728 	/* Update SOC register with new SOC */
729 	regmap_write(map, MAX17042_RepSOC, vfSoc);
730 }
731 
732 /*
733  * Block write all the override values coming from platform data.
734  * This function MUST be called before the POR initialization proceedure
735  * specified by maxim.
736  */
737 static inline void max17042_override_por_values(struct max17042_chip *chip)
738 {
739 	struct regmap *map = chip->regmap;
740 	struct max17042_config_data *config = chip->pdata->config_data;
741 
742 	max17042_override_por(map, MAX17042_TGAIN, config->tgain);
743 	max17042_override_por(map, MAx17042_TOFF, config->toff);
744 	max17042_override_por(map, MAX17042_CGAIN, config->cgain);
745 	max17042_override_por(map, MAX17042_COFF, config->coff);
746 
747 	max17042_override_por(map, MAX17042_VALRT_Th, config->valrt_thresh);
748 	max17042_override_por(map, MAX17042_TALRT_Th, config->talrt_thresh);
749 	max17042_override_por(map, MAX17042_SALRT_Th,
750 						config->soc_alrt_thresh);
751 	max17042_override_por(map, MAX17042_CONFIG, config->config);
752 	max17042_override_por(map, MAX17042_SHDNTIMER, config->shdntimer);
753 
754 	max17042_override_por(map, MAX17042_DesignCap, config->design_cap);
755 	max17042_override_por(map, MAX17042_ICHGTerm, config->ichgt_term);
756 
757 	max17042_override_por(map, MAX17042_AtRate, config->at_rate);
758 	max17042_override_por(map, MAX17042_LearnCFG, config->learn_cfg);
759 	max17042_override_por(map, MAX17042_FilterCFG, config->filter_cfg);
760 	max17042_override_por(map, MAX17042_RelaxCFG, config->relax_cfg);
761 	max17042_override_por(map, MAX17042_MiscCFG, config->misc_cfg);
762 	max17042_override_por(map, MAX17042_MaskSOC, config->masksoc);
763 
764 	max17042_override_por(map, MAX17042_FullCAP, config->fullcap);
765 	max17042_override_por(map, MAX17042_FullCAPNom, config->fullcapnom);
766 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
767 		max17042_override_por(map, MAX17042_SOC_empty,
768 						config->socempty);
769 	max17042_override_por(map, MAX17042_LAvg_empty, config->lavg_empty);
770 	max17042_override_por(map, MAX17042_dQacc, config->dqacc);
771 	max17042_override_por(map, MAX17042_dPacc, config->dpacc);
772 
773 	if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
774 		max17042_override_por(map, MAX17042_V_empty, config->vempty);
775 	else
776 		max17042_override_por(map, MAX17047_V_empty, config->vempty);
777 	max17042_override_por(map, MAX17042_TempNom, config->temp_nom);
778 	max17042_override_por(map, MAX17042_TempLim, config->temp_lim);
779 	max17042_override_por(map, MAX17042_FCTC, config->fctc);
780 	max17042_override_por(map, MAX17042_RCOMP0, config->rcomp0);
781 	max17042_override_por(map, MAX17042_TempCo, config->tcompc0);
782 	if (chip->chip_type) {
783 		max17042_override_por(map, MAX17042_EmptyTempCo,
784 						config->empty_tempco);
785 		max17042_override_por(map, MAX17042_K_empty0,
786 						config->kempty0);
787 	}
788 }
789 
790 static int max17042_init_chip(struct max17042_chip *chip)
791 {
792 	struct regmap *map = chip->regmap;
793 	int ret;
794 
795 	max17042_override_por_values(chip);
796 	/* After Power up, the MAX17042 requires 500mS in order
797 	 * to perform signal debouncing and initial SOC reporting
798 	 */
799 	msleep(500);
800 
801 	/* Initialize configaration */
802 	max17042_write_config_regs(chip);
803 
804 	/* write cell characterization data */
805 	ret = max17042_init_model(chip);
806 	if (ret) {
807 		dev_err(&chip->client->dev, "%s init failed\n",
808 			__func__);
809 		return -EIO;
810 	}
811 
812 	ret = max17042_verify_model_lock(chip);
813 	if (ret) {
814 		dev_err(&chip->client->dev, "%s lock verify failed\n",
815 			__func__);
816 		return -EIO;
817 	}
818 	/* write custom parameters */
819 	max17042_write_custom_regs(chip);
820 
821 	/* update capacity params */
822 	max17042_update_capacity_regs(chip);
823 
824 	/* delay must be atleast 350mS to allow VFSOC
825 	 * to be calculated from the new configuration
826 	 */
827 	msleep(350);
828 
829 	/* reset vfsoc0 reg */
830 	max17042_reset_vfsoc0_reg(chip);
831 
832 	/* load new capacity params */
833 	max17042_load_new_capacity_params(chip);
834 
835 	/* Init complete, Clear the POR bit */
836 	regmap_update_bits(map, MAX17042_STATUS, STATUS_POR_BIT, 0x0);
837 	return 0;
838 }
839 
840 static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
841 {
842 	struct regmap *map = chip->regmap;
843 	u32 soc, soc_tr;
844 
845 	/* program interrupt thesholds such that we should
846 	 * get interrupt for every 'off' perc change in the soc
847 	 */
848 	regmap_read(map, MAX17042_RepSOC, &soc);
849 	soc >>= 8;
850 	soc_tr = (soc + off) << 8;
851 	soc_tr |= (soc - off);
852 	regmap_write(map, MAX17042_SALRT_Th, soc_tr);
853 }
854 
855 static irqreturn_t max17042_thread_handler(int id, void *dev)
856 {
857 	struct max17042_chip *chip = dev;
858 	u32 val;
859 
860 	regmap_read(chip->regmap, MAX17042_STATUS, &val);
861 	if ((val & STATUS_INTR_SOCMIN_BIT) ||
862 		(val & STATUS_INTR_SOCMAX_BIT)) {
863 		dev_info(&chip->client->dev, "SOC threshold INTR\n");
864 		max17042_set_soc_threshold(chip, 1);
865 	}
866 
867 	power_supply_changed(chip->battery);
868 	return IRQ_HANDLED;
869 }
870 
871 static void max17042_init_worker(struct work_struct *work)
872 {
873 	struct max17042_chip *chip = container_of(work,
874 				struct max17042_chip, work);
875 	int ret;
876 
877 	/* Initialize registers according to values from the platform data */
878 	if (chip->pdata->enable_por_init && chip->pdata->config_data) {
879 		ret = max17042_init_chip(chip);
880 		if (ret)
881 			return;
882 	}
883 
884 	chip->init_complete = 1;
885 }
886 
887 #ifdef CONFIG_OF
888 static struct max17042_platform_data *
889 max17042_get_of_pdata(struct max17042_chip *chip)
890 {
891 	struct device *dev = &chip->client->dev;
892 	struct device_node *np = dev->of_node;
893 	u32 prop;
894 	struct max17042_platform_data *pdata;
895 
896 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
897 	if (!pdata)
898 		return NULL;
899 
900 	/*
901 	 * Require current sense resistor value to be specified for
902 	 * current-sense functionality to be enabled at all.
903 	 */
904 	if (of_property_read_u32(np, "maxim,rsns-microohm", &prop) == 0) {
905 		pdata->r_sns = prop;
906 		pdata->enable_current_sense = true;
907 	}
908 
909 	if (of_property_read_s32(np, "maxim,cold-temp", &pdata->temp_min))
910 		pdata->temp_min = INT_MIN;
911 	if (of_property_read_s32(np, "maxim,over-heat-temp", &pdata->temp_max))
912 		pdata->temp_max = INT_MAX;
913 	if (of_property_read_s32(np, "maxim,dead-volt", &pdata->vmin))
914 		pdata->vmin = INT_MIN;
915 	if (of_property_read_s32(np, "maxim,over-volt", &pdata->vmax))
916 		pdata->vmax = INT_MAX;
917 
918 	return pdata;
919 }
920 #endif
921 
922 static struct max17042_reg_data max17047_default_pdata_init_regs[] = {
923 	/*
924 	 * Some firmwares do not set FullSOCThr, Enable End-of-Charge Detection
925 	 * when the voltage FG reports 95%, as recommended in the datasheet.
926 	 */
927 	{ MAX17047_FullSOCThr, MAX17042_BATTERY_FULL << 8 },
928 };
929 
930 static struct max17042_platform_data *
931 max17042_get_default_pdata(struct max17042_chip *chip)
932 {
933 	struct device *dev = &chip->client->dev;
934 	struct max17042_platform_data *pdata;
935 	int ret, misc_cfg;
936 
937 	/*
938 	 * The MAX17047 gets used on x86 where we might not have pdata, assume
939 	 * the firmware will already have initialized the fuel-gauge and provide
940 	 * default values for the non init bits to make things work.
941 	 */
942 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
943 	if (!pdata)
944 		return pdata;
945 
946 	if (chip->chip_type != MAXIM_DEVICE_TYPE_MAX17042) {
947 		pdata->init_data = max17047_default_pdata_init_regs;
948 		pdata->num_init_data =
949 			ARRAY_SIZE(max17047_default_pdata_init_regs);
950 	}
951 
952 	ret = regmap_read(chip->regmap, MAX17042_MiscCFG, &misc_cfg);
953 	if (ret < 0)
954 		return NULL;
955 
956 	/* If bits 0-1 are set to 3 then only Voltage readings are used */
957 	if ((misc_cfg & 0x3) == 0x3)
958 		pdata->enable_current_sense = false;
959 	else
960 		pdata->enable_current_sense = true;
961 
962 	pdata->vmin = MAX17042_DEFAULT_VMIN;
963 	pdata->vmax = MAX17042_DEFAULT_VMAX;
964 	pdata->temp_min = MAX17042_DEFAULT_TEMP_MIN;
965 	pdata->temp_max = MAX17042_DEFAULT_TEMP_MAX;
966 
967 	return pdata;
968 }
969 
970 static struct max17042_platform_data *
971 max17042_get_pdata(struct max17042_chip *chip)
972 {
973 	struct device *dev = &chip->client->dev;
974 
975 #ifdef CONFIG_OF
976 	if (dev->of_node)
977 		return max17042_get_of_pdata(chip);
978 #endif
979 	if (dev->platform_data)
980 		return dev->platform_data;
981 
982 	return max17042_get_default_pdata(chip);
983 }
984 
985 static const struct regmap_config max17042_regmap_config = {
986 	.reg_bits = 8,
987 	.val_bits = 16,
988 	.val_format_endian = REGMAP_ENDIAN_NATIVE,
989 };
990 
991 static const struct power_supply_desc max17042_psy_desc = {
992 	.name		= "max170xx_battery",
993 	.type		= POWER_SUPPLY_TYPE_BATTERY,
994 	.get_property	= max17042_get_property,
995 	.set_property	= max17042_set_property,
996 	.property_is_writeable	= max17042_property_is_writeable,
997 	.external_power_changed	= max17042_external_power_changed,
998 	.properties	= max17042_battery_props,
999 	.num_properties	= ARRAY_SIZE(max17042_battery_props),
1000 };
1001 
1002 static const struct power_supply_desc max17042_no_current_sense_psy_desc = {
1003 	.name		= "max170xx_battery",
1004 	.type		= POWER_SUPPLY_TYPE_BATTERY,
1005 	.get_property	= max17042_get_property,
1006 	.set_property	= max17042_set_property,
1007 	.property_is_writeable	= max17042_property_is_writeable,
1008 	.properties	= max17042_battery_props,
1009 	.num_properties	= ARRAY_SIZE(max17042_battery_props) - 2,
1010 };
1011 
1012 static int max17042_probe(struct i2c_client *client,
1013 			const struct i2c_device_id *id)
1014 {
1015 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
1016 	const struct power_supply_desc *max17042_desc = &max17042_psy_desc;
1017 	struct power_supply_config psy_cfg = {};
1018 	const struct acpi_device_id *acpi_id = NULL;
1019 	struct device *dev = &client->dev;
1020 	struct max17042_chip *chip;
1021 	int ret;
1022 	int i;
1023 	u32 val;
1024 
1025 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
1026 		return -EIO;
1027 
1028 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
1029 	if (!chip)
1030 		return -ENOMEM;
1031 
1032 	chip->client = client;
1033 	if (id) {
1034 		chip->chip_type = id->driver_data;
1035 	} else {
1036 		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
1037 		if (!acpi_id)
1038 			return -ENODEV;
1039 
1040 		chip->chip_type = acpi_id->driver_data;
1041 	}
1042 	chip->regmap = devm_regmap_init_i2c(client, &max17042_regmap_config);
1043 	if (IS_ERR(chip->regmap)) {
1044 		dev_err(&client->dev, "Failed to initialize regmap\n");
1045 		return -EINVAL;
1046 	}
1047 
1048 	chip->pdata = max17042_get_pdata(chip);
1049 	if (!chip->pdata) {
1050 		dev_err(&client->dev, "no platform data provided\n");
1051 		return -EINVAL;
1052 	}
1053 
1054 	i2c_set_clientdata(client, chip);
1055 	psy_cfg.drv_data = chip;
1056 
1057 	/* When current is not measured,
1058 	 * CURRENT_NOW and CURRENT_AVG properties should be invisible. */
1059 	if (!chip->pdata->enable_current_sense)
1060 		max17042_desc = &max17042_no_current_sense_psy_desc;
1061 
1062 	if (chip->pdata->r_sns == 0)
1063 		chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR;
1064 
1065 	if (chip->pdata->init_data)
1066 		for (i = 0; i < chip->pdata->num_init_data; i++)
1067 			regmap_write(chip->regmap,
1068 					chip->pdata->init_data[i].addr,
1069 					chip->pdata->init_data[i].data);
1070 
1071 	if (!chip->pdata->enable_current_sense) {
1072 		regmap_write(chip->regmap, MAX17042_CGAIN, 0x0000);
1073 		regmap_write(chip->regmap, MAX17042_MiscCFG, 0x0003);
1074 		regmap_write(chip->regmap, MAX17042_LearnCFG, 0x0007);
1075 	}
1076 
1077 	chip->battery = devm_power_supply_register(&client->dev, max17042_desc,
1078 						   &psy_cfg);
1079 	if (IS_ERR(chip->battery)) {
1080 		dev_err(&client->dev, "failed: power supply register\n");
1081 		return PTR_ERR(chip->battery);
1082 	}
1083 
1084 	if (client->irq) {
1085 		unsigned int flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
1086 
1087 		/*
1088 		 * On ACPI systems the IRQ may be handled by ACPI-event code,
1089 		 * so we need to share (if the ACPI code is willing to share).
1090 		 */
1091 		if (acpi_id)
1092 			flags |= IRQF_SHARED | IRQF_PROBE_SHARED;
1093 
1094 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1095 						NULL,
1096 						max17042_thread_handler, flags,
1097 						chip->battery->desc->name,
1098 						chip);
1099 		if (!ret) {
1100 			regmap_update_bits(chip->regmap, MAX17042_CONFIG,
1101 					CONFIG_ALRT_BIT_ENBL,
1102 					CONFIG_ALRT_BIT_ENBL);
1103 			max17042_set_soc_threshold(chip, 1);
1104 		} else {
1105 			client->irq = 0;
1106 			if (ret != -EBUSY)
1107 				dev_err(&client->dev, "Failed to get IRQ\n");
1108 		}
1109 	}
1110 	/* Not able to update the charge threshold when exceeded? -> disable */
1111 	if (!client->irq)
1112 		regmap_write(chip->regmap, MAX17042_SALRT_Th, 0xff00);
1113 
1114 	regmap_read(chip->regmap, MAX17042_STATUS, &val);
1115 	if (val & STATUS_POR_BIT) {
1116 		INIT_WORK(&chip->work, max17042_init_worker);
1117 		schedule_work(&chip->work);
1118 	} else {
1119 		chip->init_complete = 1;
1120 	}
1121 
1122 	return 0;
1123 }
1124 
1125 #ifdef CONFIG_PM_SLEEP
1126 static int max17042_suspend(struct device *dev)
1127 {
1128 	struct max17042_chip *chip = dev_get_drvdata(dev);
1129 
1130 	/*
1131 	 * disable the irq and enable irq_wake
1132 	 * capability to the interrupt line.
1133 	 */
1134 	if (chip->client->irq) {
1135 		disable_irq(chip->client->irq);
1136 		enable_irq_wake(chip->client->irq);
1137 	}
1138 
1139 	return 0;
1140 }
1141 
1142 static int max17042_resume(struct device *dev)
1143 {
1144 	struct max17042_chip *chip = dev_get_drvdata(dev);
1145 
1146 	if (chip->client->irq) {
1147 		disable_irq_wake(chip->client->irq);
1148 		enable_irq(chip->client->irq);
1149 		/* re-program the SOC thresholds to 1% change */
1150 		max17042_set_soc_threshold(chip, 1);
1151 	}
1152 
1153 	return 0;
1154 }
1155 #endif
1156 
1157 static SIMPLE_DEV_PM_OPS(max17042_pm_ops, max17042_suspend,
1158 			max17042_resume);
1159 
1160 #ifdef CONFIG_ACPI
1161 static const struct acpi_device_id max17042_acpi_match[] = {
1162 	{ "MAX17047", MAXIM_DEVICE_TYPE_MAX17047 },
1163 	{ }
1164 };
1165 MODULE_DEVICE_TABLE(acpi, max17042_acpi_match);
1166 #endif
1167 
1168 #ifdef CONFIG_OF
1169 static const struct of_device_id max17042_dt_match[] = {
1170 	{ .compatible = "maxim,max17042" },
1171 	{ .compatible = "maxim,max17047" },
1172 	{ .compatible = "maxim,max17050" },
1173 	{ },
1174 };
1175 MODULE_DEVICE_TABLE(of, max17042_dt_match);
1176 #endif
1177 
1178 static const struct i2c_device_id max17042_id[] = {
1179 	{ "max17042", MAXIM_DEVICE_TYPE_MAX17042 },
1180 	{ "max17047", MAXIM_DEVICE_TYPE_MAX17047 },
1181 	{ "max17050", MAXIM_DEVICE_TYPE_MAX17050 },
1182 	{ }
1183 };
1184 MODULE_DEVICE_TABLE(i2c, max17042_id);
1185 
1186 static struct i2c_driver max17042_i2c_driver = {
1187 	.driver	= {
1188 		.name	= "max17042",
1189 		.acpi_match_table = ACPI_PTR(max17042_acpi_match),
1190 		.of_match_table = of_match_ptr(max17042_dt_match),
1191 		.pm	= &max17042_pm_ops,
1192 	},
1193 	.probe		= max17042_probe,
1194 	.id_table	= max17042_id,
1195 };
1196 module_i2c_driver(max17042_i2c_driver);
1197 
1198 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1199 MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
1200 MODULE_LICENSE("GPL");
1201