1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Spreadtrum Communications Inc.
3 
4 #include <linux/gpio/consumer.h>
5 #include <linux/iio/consumer.h>
6 #include <linux/interrupt.h>
7 #include <linux/kernel.h>
8 #include <linux/math64.h>
9 #include <linux/module.h>
10 #include <linux/nvmem-consumer.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/power_supply.h>
14 #include <linux/regmap.h>
15 #include <linux/slab.h>
16 
17 /* PMIC global control registers definition */
18 #define SC27XX_MODULE_EN0		0xc08
19 #define SC27XX_CLK_EN0			0xc18
20 #define SC27XX_FGU_EN			BIT(7)
21 #define SC27XX_FGU_RTC_EN		BIT(6)
22 
23 /* FGU registers definition */
24 #define SC27XX_FGU_START		0x0
25 #define SC27XX_FGU_CONFIG		0x4
26 #define SC27XX_FGU_ADC_CONFIG		0x8
27 #define SC27XX_FGU_STATUS		0xc
28 #define SC27XX_FGU_INT_EN		0x10
29 #define SC27XX_FGU_INT_CLR		0x14
30 #define SC27XX_FGU_INT_STS		0x1c
31 #define SC27XX_FGU_VOLTAGE		0x20
32 #define SC27XX_FGU_OCV			0x24
33 #define SC27XX_FGU_POCV			0x28
34 #define SC27XX_FGU_CURRENT		0x2c
35 #define SC27XX_FGU_LOW_OVERLOAD		0x34
36 #define SC27XX_FGU_CLBCNT_SETH		0x50
37 #define SC27XX_FGU_CLBCNT_SETL		0x54
38 #define SC27XX_FGU_CLBCNT_DELTH		0x58
39 #define SC27XX_FGU_CLBCNT_DELTL		0x5c
40 #define SC27XX_FGU_CLBCNT_VALH		0x68
41 #define SC27XX_FGU_CLBCNT_VALL		0x6c
42 #define SC27XX_FGU_CLBCNT_QMAXL		0x74
43 #define SC27XX_FGU_USER_AREA_SET	0xa0
44 #define SC27XX_FGU_USER_AREA_CLEAR	0xa4
45 #define SC27XX_FGU_USER_AREA_STATUS	0xa8
46 #define SC27XX_FGU_VOLTAGE_BUF		0xd0
47 #define SC27XX_FGU_CURRENT_BUF		0xf0
48 
49 #define SC27XX_WRITE_SELCLB_EN		BIT(0)
50 #define SC27XX_FGU_CLBCNT_MASK		GENMASK(15, 0)
51 #define SC27XX_FGU_CLBCNT_SHIFT		16
52 #define SC27XX_FGU_LOW_OVERLOAD_MASK	GENMASK(12, 0)
53 
54 #define SC27XX_FGU_INT_MASK		GENMASK(9, 0)
55 #define SC27XX_FGU_LOW_OVERLOAD_INT	BIT(0)
56 #define SC27XX_FGU_CLBCNT_DELTA_INT	BIT(2)
57 
58 #define SC27XX_FGU_MODE_AREA_MASK	GENMASK(15, 12)
59 #define SC27XX_FGU_CAP_AREA_MASK	GENMASK(11, 0)
60 #define SC27XX_FGU_MODE_AREA_SHIFT	12
61 
62 #define SC27XX_FGU_FIRST_POWERTON	GENMASK(3, 0)
63 #define SC27XX_FGU_DEFAULT_CAP		GENMASK(11, 0)
64 #define SC27XX_FGU_NORMAIL_POWERTON	0x5
65 
66 #define SC27XX_FGU_CUR_BASIC_ADC	8192
67 #define SC27XX_FGU_SAMPLE_HZ		2
68 /* micro Ohms */
69 #define SC27XX_FGU_IDEAL_RESISTANCE	20000
70 
71 /*
72  * struct sc27xx_fgu_data: describe the FGU device
73  * @regmap: regmap for register access
74  * @dev: platform device
75  * @battery: battery power supply
76  * @base: the base offset for the controller
77  * @lock: protect the structure
78  * @gpiod: GPIO for battery detection
79  * @channel: IIO channel to get battery temperature
80  * @charge_chan: IIO channel to get charge voltage
81  * @internal_resist: the battery internal resistance in mOhm
82  * @total_cap: the total capacity of the battery in mAh
83  * @init_cap: the initial capacity of the battery in mAh
84  * @alarm_cap: the alarm capacity
85  * @init_clbcnt: the initial coulomb counter
86  * @max_volt: the maximum constant input voltage in millivolt
87  * @min_volt: the minimum drained battery voltage in microvolt
88  * @boot_volt: the voltage measured during boot in microvolt
89  * @table_len: the capacity table length
90  * @resist_table_len: the resistance table length
91  * @cur_1000ma_adc: ADC value corresponding to 1000 mA
92  * @vol_1000mv_adc: ADC value corresponding to 1000 mV
93  * @calib_resist: the real resistance of coulomb counter chip in uOhm
94  * @cap_table: capacity table with corresponding ocv
95  * @resist_table: resistance percent table with corresponding temperature
96  */
97 struct sc27xx_fgu_data {
98 	struct regmap *regmap;
99 	struct device *dev;
100 	struct power_supply *battery;
101 	u32 base;
102 	struct mutex lock;
103 	struct gpio_desc *gpiod;
104 	struct iio_channel *channel;
105 	struct iio_channel *charge_chan;
106 	bool bat_present;
107 	int internal_resist;
108 	int total_cap;
109 	int init_cap;
110 	int alarm_cap;
111 	int init_clbcnt;
112 	int max_volt;
113 	int min_volt;
114 	int boot_volt;
115 	int table_len;
116 	int resist_table_len;
117 	int cur_1000ma_adc;
118 	int vol_1000mv_adc;
119 	int calib_resist;
120 	struct power_supply_battery_ocv_table *cap_table;
121 	struct power_supply_resistance_temp_table *resist_table;
122 };
123 
124 static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity);
125 static void sc27xx_fgu_capacity_calibration(struct sc27xx_fgu_data *data,
126 					    int cap, bool int_mode);
127 static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap);
128 static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp);
129 
130 static const char * const sc27xx_charger_supply_name[] = {
131 	"sc2731_charger",
132 	"sc2720_charger",
133 	"sc2721_charger",
134 	"sc2723_charger",
135 };
136 
137 static int sc27xx_fgu_adc_to_current(struct sc27xx_fgu_data *data, s64 adc)
138 {
139 	return DIV_S64_ROUND_CLOSEST(adc * 1000, data->cur_1000ma_adc);
140 }
141 
142 static int sc27xx_fgu_adc_to_voltage(struct sc27xx_fgu_data *data, s64 adc)
143 {
144 	return DIV_S64_ROUND_CLOSEST(adc * 1000, data->vol_1000mv_adc);
145 }
146 
147 static int sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data *data, int vol)
148 {
149 	return DIV_ROUND_CLOSEST(vol * data->vol_1000mv_adc, 1000);
150 }
151 
152 static bool sc27xx_fgu_is_first_poweron(struct sc27xx_fgu_data *data)
153 {
154 	int ret, status, cap, mode;
155 
156 	ret = regmap_read(data->regmap,
157 			  data->base + SC27XX_FGU_USER_AREA_STATUS, &status);
158 	if (ret)
159 		return false;
160 
161 	/*
162 	 * We use low 4 bits to save the last battery capacity and high 12 bits
163 	 * to save the system boot mode.
164 	 */
165 	mode = (status & SC27XX_FGU_MODE_AREA_MASK) >> SC27XX_FGU_MODE_AREA_SHIFT;
166 	cap = status & SC27XX_FGU_CAP_AREA_MASK;
167 
168 	/*
169 	 * When FGU has been powered down, the user area registers became
170 	 * default value (0xffff), which can be used to valid if the system is
171 	 * first power on or not.
172 	 */
173 	if (mode == SC27XX_FGU_FIRST_POWERTON || cap == SC27XX_FGU_DEFAULT_CAP)
174 		return true;
175 
176 	return false;
177 }
178 
179 static int sc27xx_fgu_save_boot_mode(struct sc27xx_fgu_data *data,
180 				     int boot_mode)
181 {
182 	int ret;
183 
184 	ret = regmap_update_bits(data->regmap,
185 				 data->base + SC27XX_FGU_USER_AREA_CLEAR,
186 				 SC27XX_FGU_MODE_AREA_MASK,
187 				 SC27XX_FGU_MODE_AREA_MASK);
188 	if (ret)
189 		return ret;
190 
191 	/*
192 	 * Since the user area registers are put on power always-on region,
193 	 * then these registers changing time will be a little long. Thus
194 	 * here we should delay 200us to wait until values are updated
195 	 * successfully according to the datasheet.
196 	 */
197 	udelay(200);
198 
199 	ret = regmap_update_bits(data->regmap,
200 				 data->base + SC27XX_FGU_USER_AREA_SET,
201 				 SC27XX_FGU_MODE_AREA_MASK,
202 				 boot_mode << SC27XX_FGU_MODE_AREA_SHIFT);
203 	if (ret)
204 		return ret;
205 
206 	/*
207 	 * Since the user area registers are put on power always-on region,
208 	 * then these registers changing time will be a little long. Thus
209 	 * here we should delay 200us to wait until values are updated
210 	 * successfully according to the datasheet.
211 	 */
212 	udelay(200);
213 
214 	/*
215 	 * According to the datasheet, we should set the USER_AREA_CLEAR to 0 to
216 	 * make the user area data available, otherwise we can not save the user
217 	 * area data.
218 	 */
219 	return regmap_update_bits(data->regmap,
220 				  data->base + SC27XX_FGU_USER_AREA_CLEAR,
221 				  SC27XX_FGU_MODE_AREA_MASK, 0);
222 }
223 
224 static int sc27xx_fgu_save_last_cap(struct sc27xx_fgu_data *data, int cap)
225 {
226 	int ret;
227 
228 	ret = regmap_update_bits(data->regmap,
229 				 data->base + SC27XX_FGU_USER_AREA_CLEAR,
230 				 SC27XX_FGU_CAP_AREA_MASK,
231 				 SC27XX_FGU_CAP_AREA_MASK);
232 	if (ret)
233 		return ret;
234 
235 	/*
236 	 * Since the user area registers are put on power always-on region,
237 	 * then these registers changing time will be a little long. Thus
238 	 * here we should delay 200us to wait until values are updated
239 	 * successfully according to the datasheet.
240 	 */
241 	udelay(200);
242 
243 	ret = regmap_update_bits(data->regmap,
244 				 data->base + SC27XX_FGU_USER_AREA_SET,
245 				 SC27XX_FGU_CAP_AREA_MASK, cap);
246 	if (ret)
247 		return ret;
248 
249 	/*
250 	 * Since the user area registers are put on power always-on region,
251 	 * then these registers changing time will be a little long. Thus
252 	 * here we should delay 200us to wait until values are updated
253 	 * successfully according to the datasheet.
254 	 */
255 	udelay(200);
256 
257 	/*
258 	 * According to the datasheet, we should set the USER_AREA_CLEAR to 0 to
259 	 * make the user area data available, otherwise we can not save the user
260 	 * area data.
261 	 */
262 	return regmap_update_bits(data->regmap,
263 				  data->base + SC27XX_FGU_USER_AREA_CLEAR,
264 				  SC27XX_FGU_CAP_AREA_MASK, 0);
265 }
266 
267 static int sc27xx_fgu_read_last_cap(struct sc27xx_fgu_data *data, int *cap)
268 {
269 	int ret, value;
270 
271 	ret = regmap_read(data->regmap,
272 			  data->base + SC27XX_FGU_USER_AREA_STATUS, &value);
273 	if (ret)
274 		return ret;
275 
276 	*cap = value & SC27XX_FGU_CAP_AREA_MASK;
277 	return 0;
278 }
279 
280 /*
281  * When system boots on, we can not read battery capacity from coulomb
282  * registers, since now the coulomb registers are invalid. So we should
283  * calculate the battery open circuit voltage, and get current battery
284  * capacity according to the capacity table.
285  */
286 static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
287 {
288 	int volt, cur, oci, ocv, ret;
289 	bool is_first_poweron = sc27xx_fgu_is_first_poweron(data);
290 
291 	/*
292 	 * If system is not the first power on, we should use the last saved
293 	 * battery capacity as the initial battery capacity. Otherwise we should
294 	 * re-calculate the initial battery capacity.
295 	 */
296 	if (!is_first_poweron) {
297 		ret = sc27xx_fgu_read_last_cap(data, cap);
298 		if (ret)
299 			return ret;
300 
301 		return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
302 	}
303 
304 	/*
305 	 * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
306 	 * the first sampled open circuit current.
307 	 */
308 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
309 			  &cur);
310 	if (ret)
311 		return ret;
312 
313 	cur <<= 1;
314 	oci = sc27xx_fgu_adc_to_current(data, cur - SC27XX_FGU_CUR_BASIC_ADC);
315 
316 	/*
317 	 * Should get the OCV from SC27XX_FGU_POCV register at the system
318 	 * beginning. It is ADC values reading from registers which need to
319 	 * convert the corresponding voltage.
320 	 */
321 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
322 	if (ret)
323 		return ret;
324 
325 	volt = sc27xx_fgu_adc_to_voltage(data, volt);
326 	ocv = volt * 1000 - oci * data->internal_resist;
327 	data->boot_volt = ocv;
328 
329 	/*
330 	 * Parse the capacity table to look up the correct capacity percent
331 	 * according to current battery's corresponding OCV values.
332 	 */
333 	*cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
334 					   ocv);
335 
336 	ret = sc27xx_fgu_save_last_cap(data, *cap);
337 	if (ret)
338 		return ret;
339 
340 	return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
341 }
342 
343 static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
344 {
345 	int ret;
346 
347 	ret = regmap_update_bits(data->regmap,
348 				 data->base + SC27XX_FGU_CLBCNT_SETL,
349 				 SC27XX_FGU_CLBCNT_MASK, clbcnt);
350 	if (ret)
351 		return ret;
352 
353 	ret = regmap_update_bits(data->regmap,
354 				 data->base + SC27XX_FGU_CLBCNT_SETH,
355 				 SC27XX_FGU_CLBCNT_MASK,
356 				 clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
357 	if (ret)
358 		return ret;
359 
360 	return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
361 				 SC27XX_WRITE_SELCLB_EN,
362 				 SC27XX_WRITE_SELCLB_EN);
363 }
364 
365 static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
366 {
367 	int ccl, cch, ret;
368 
369 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
370 			  &ccl);
371 	if (ret)
372 		return ret;
373 
374 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
375 			  &cch);
376 	if (ret)
377 		return ret;
378 
379 	*clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
380 	*clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
381 
382 	return 0;
383 }
384 
385 static int sc27xx_fgu_get_vol_now(struct sc27xx_fgu_data *data, int *val)
386 {
387 	int ret;
388 	u32 vol;
389 
390 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE_BUF,
391 			  &vol);
392 	if (ret)
393 		return ret;
394 
395 	/*
396 	 * It is ADC values reading from registers which need to convert to
397 	 * corresponding voltage values.
398 	 */
399 	*val = sc27xx_fgu_adc_to_voltage(data, vol);
400 
401 	return 0;
402 }
403 
404 static int sc27xx_fgu_get_cur_now(struct sc27xx_fgu_data *data, int *val)
405 {
406 	int ret;
407 	u32 cur;
408 
409 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT_BUF,
410 			  &cur);
411 	if (ret)
412 		return ret;
413 
414 	/*
415 	 * It is ADC values reading from registers which need to convert to
416 	 * corresponding current values.
417 	 */
418 	*val = sc27xx_fgu_adc_to_current(data, cur - SC27XX_FGU_CUR_BASIC_ADC);
419 
420 	return 0;
421 }
422 
423 static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
424 {
425 	int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
426 
427 	/* Get current coulomb counters firstly */
428 	ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
429 	if (ret)
430 		return ret;
431 
432 	delta_clbcnt = cur_clbcnt - data->init_clbcnt;
433 
434 	/*
435 	 * Convert coulomb counter to delta capacity (mAh), and set multiplier
436 	 * as 10 to improve the precision.
437 	 */
438 	temp = DIV_ROUND_CLOSEST(delta_clbcnt * 10, 36 * SC27XX_FGU_SAMPLE_HZ);
439 	temp = sc27xx_fgu_adc_to_current(data, temp / 1000);
440 
441 	/*
442 	 * Convert to capacity percent of the battery total capacity,
443 	 * and multiplier is 100 too.
444 	 */
445 	delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
446 	*cap = delta_cap + data->init_cap;
447 
448 	/* Calibrate the battery capacity in a normal range. */
449 	sc27xx_fgu_capacity_calibration(data, *cap, false);
450 
451 	return 0;
452 }
453 
454 static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
455 {
456 	int ret, vol;
457 
458 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
459 	if (ret)
460 		return ret;
461 
462 	/*
463 	 * It is ADC values reading from registers which need to convert to
464 	 * corresponding voltage values.
465 	 */
466 	*val = sc27xx_fgu_adc_to_voltage(data, vol);
467 
468 	return 0;
469 }
470 
471 static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
472 {
473 	int ret, cur;
474 
475 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
476 	if (ret)
477 		return ret;
478 
479 	/*
480 	 * It is ADC values reading from registers which need to convert to
481 	 * corresponding current values.
482 	 */
483 	*val = sc27xx_fgu_adc_to_current(data, cur - SC27XX_FGU_CUR_BASIC_ADC);
484 
485 	return 0;
486 }
487 
488 static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
489 {
490 	int vol, cur, ret, temp, resistance;
491 
492 	ret = sc27xx_fgu_get_vbat_vol(data, &vol);
493 	if (ret)
494 		return ret;
495 
496 	ret = sc27xx_fgu_get_current(data, &cur);
497 	if (ret)
498 		return ret;
499 
500 	resistance = data->internal_resist;
501 	if (data->resist_table_len > 0) {
502 		ret = sc27xx_fgu_get_temp(data, &temp);
503 		if (ret)
504 			return ret;
505 
506 		resistance = power_supply_temp2resist_simple(data->resist_table,
507 						data->resist_table_len, temp);
508 		resistance = data->internal_resist * resistance / 100;
509 	}
510 
511 	/* Return the battery OCV in micro volts. */
512 	*val = vol * 1000 - cur * resistance;
513 
514 	return 0;
515 }
516 
517 static int sc27xx_fgu_get_charge_vol(struct sc27xx_fgu_data *data, int *val)
518 {
519 	int ret, vol;
520 
521 	ret = iio_read_channel_processed(data->charge_chan, &vol);
522 	if (ret < 0)
523 		return ret;
524 
525 	*val = vol * 1000;
526 	return 0;
527 }
528 
529 static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
530 {
531 	return iio_read_channel_processed(data->channel, temp);
532 }
533 
534 static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
535 {
536 	int ret, vol;
537 
538 	ret = sc27xx_fgu_get_vbat_vol(data, &vol);
539 	if (ret)
540 		return ret;
541 
542 	if (vol > data->max_volt)
543 		*health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
544 	else
545 		*health = POWER_SUPPLY_HEALTH_GOOD;
546 
547 	return 0;
548 }
549 
550 static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
551 {
552 	union power_supply_propval val;
553 	struct power_supply *psy;
554 	int i, ret = -EINVAL;
555 
556 	for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
557 		psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
558 		if (!psy)
559 			continue;
560 
561 		ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
562 						&val);
563 		power_supply_put(psy);
564 		if (ret)
565 			return ret;
566 
567 		*status = val.intval;
568 	}
569 
570 	return ret;
571 }
572 
573 static int sc27xx_fgu_get_property(struct power_supply *psy,
574 				   enum power_supply_property psp,
575 				   union power_supply_propval *val)
576 {
577 	struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
578 	int ret = 0;
579 	int value;
580 
581 	mutex_lock(&data->lock);
582 
583 	switch (psp) {
584 	case POWER_SUPPLY_PROP_STATUS:
585 		ret = sc27xx_fgu_get_status(data, &value);
586 		if (ret)
587 			goto error;
588 
589 		val->intval = value;
590 		break;
591 
592 	case POWER_SUPPLY_PROP_HEALTH:
593 		ret = sc27xx_fgu_get_health(data, &value);
594 		if (ret)
595 			goto error;
596 
597 		val->intval = value;
598 		break;
599 
600 	case POWER_SUPPLY_PROP_PRESENT:
601 		val->intval = data->bat_present;
602 		break;
603 
604 	case POWER_SUPPLY_PROP_TEMP:
605 		ret = sc27xx_fgu_get_temp(data, &value);
606 		if (ret)
607 			goto error;
608 
609 		val->intval = value;
610 		break;
611 
612 	case POWER_SUPPLY_PROP_TECHNOLOGY:
613 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
614 		break;
615 
616 	case POWER_SUPPLY_PROP_CAPACITY:
617 		ret = sc27xx_fgu_get_capacity(data, &value);
618 		if (ret)
619 			goto error;
620 
621 		val->intval = value;
622 		break;
623 
624 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
625 		ret = sc27xx_fgu_get_vbat_vol(data, &value);
626 		if (ret)
627 			goto error;
628 
629 		val->intval = value * 1000;
630 		break;
631 
632 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
633 		ret = sc27xx_fgu_get_vbat_ocv(data, &value);
634 		if (ret)
635 			goto error;
636 
637 		val->intval = value;
638 		break;
639 
640 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
641 		ret = sc27xx_fgu_get_charge_vol(data, &value);
642 		if (ret)
643 			goto error;
644 
645 		val->intval = value;
646 		break;
647 
648 	case POWER_SUPPLY_PROP_CURRENT_AVG:
649 		ret = sc27xx_fgu_get_current(data, &value);
650 		if (ret)
651 			goto error;
652 
653 		val->intval = value * 1000;
654 		break;
655 
656 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
657 		val->intval = data->total_cap * 1000;
658 		break;
659 
660 	case POWER_SUPPLY_PROP_CHARGE_NOW:
661 		ret = sc27xx_fgu_get_clbcnt(data, &value);
662 		if (ret)
663 			goto error;
664 
665 		value = DIV_ROUND_CLOSEST(value * 10,
666 					  36 * SC27XX_FGU_SAMPLE_HZ);
667 		val->intval = sc27xx_fgu_adc_to_current(data, value);
668 
669 		break;
670 
671 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
672 		ret = sc27xx_fgu_get_vol_now(data, &value);
673 		if (ret)
674 			goto error;
675 
676 		val->intval = value * 1000;
677 		break;
678 
679 	case POWER_SUPPLY_PROP_CURRENT_NOW:
680 		ret = sc27xx_fgu_get_cur_now(data, &value);
681 		if (ret)
682 			goto error;
683 
684 		val->intval = value * 1000;
685 		break;
686 
687 	case POWER_SUPPLY_PROP_VOLTAGE_BOOT:
688 		val->intval = data->boot_volt;
689 		break;
690 
691 	default:
692 		ret = -EINVAL;
693 		break;
694 	}
695 
696 error:
697 	mutex_unlock(&data->lock);
698 	return ret;
699 }
700 
701 static int sc27xx_fgu_set_property(struct power_supply *psy,
702 				   enum power_supply_property psp,
703 				   const union power_supply_propval *val)
704 {
705 	struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
706 	int ret;
707 
708 	mutex_lock(&data->lock);
709 
710 	switch (psp) {
711 	case POWER_SUPPLY_PROP_CAPACITY:
712 		ret = sc27xx_fgu_save_last_cap(data, val->intval);
713 		if (ret < 0)
714 			dev_err(data->dev, "failed to save battery capacity\n");
715 		break;
716 
717 	case POWER_SUPPLY_PROP_CALIBRATE:
718 		sc27xx_fgu_adjust_cap(data, val->intval);
719 		ret = 0;
720 		break;
721 
722 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
723 		data->total_cap = val->intval / 1000;
724 		ret = 0;
725 		break;
726 
727 	default:
728 		ret = -EINVAL;
729 	}
730 
731 	mutex_unlock(&data->lock);
732 
733 	return ret;
734 }
735 
736 static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
737 {
738 	struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
739 
740 	power_supply_changed(data->battery);
741 }
742 
743 static int sc27xx_fgu_property_is_writeable(struct power_supply *psy,
744 					    enum power_supply_property psp)
745 {
746 	return psp == POWER_SUPPLY_PROP_CAPACITY ||
747 		psp == POWER_SUPPLY_PROP_CALIBRATE ||
748 		psp == POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
749 }
750 
751 static enum power_supply_property sc27xx_fgu_props[] = {
752 	POWER_SUPPLY_PROP_STATUS,
753 	POWER_SUPPLY_PROP_HEALTH,
754 	POWER_SUPPLY_PROP_PRESENT,
755 	POWER_SUPPLY_PROP_TEMP,
756 	POWER_SUPPLY_PROP_TECHNOLOGY,
757 	POWER_SUPPLY_PROP_CAPACITY,
758 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
759 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
760 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
761 	POWER_SUPPLY_PROP_VOLTAGE_BOOT,
762 	POWER_SUPPLY_PROP_CURRENT_NOW,
763 	POWER_SUPPLY_PROP_CURRENT_AVG,
764 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
765 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
766 	POWER_SUPPLY_PROP_CALIBRATE,
767 	POWER_SUPPLY_PROP_CHARGE_NOW
768 };
769 
770 static const struct power_supply_desc sc27xx_fgu_desc = {
771 	.name			= "sc27xx-fgu",
772 	.type			= POWER_SUPPLY_TYPE_BATTERY,
773 	.properties		= sc27xx_fgu_props,
774 	.num_properties		= ARRAY_SIZE(sc27xx_fgu_props),
775 	.get_property		= sc27xx_fgu_get_property,
776 	.set_property		= sc27xx_fgu_set_property,
777 	.external_power_changed	= sc27xx_fgu_external_power_changed,
778 	.property_is_writeable	= sc27xx_fgu_property_is_writeable,
779 	.no_thermal		= true,
780 };
781 
782 static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap)
783 {
784 	int ret;
785 
786 	data->init_cap = cap;
787 	ret = sc27xx_fgu_get_clbcnt(data, &data->init_clbcnt);
788 	if (ret)
789 		dev_err(data->dev, "failed to get init coulomb counter\n");
790 }
791 
792 static void sc27xx_fgu_capacity_calibration(struct sc27xx_fgu_data *data,
793 					    int cap, bool int_mode)
794 {
795 	int ret, ocv, chg_sts, adc;
796 
797 	ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
798 	if (ret) {
799 		dev_err(data->dev, "get battery ocv error.\n");
800 		return;
801 	}
802 
803 	ret = sc27xx_fgu_get_status(data, &chg_sts);
804 	if (ret) {
805 		dev_err(data->dev, "get charger status error.\n");
806 		return;
807 	}
808 
809 	/*
810 	 * If we are in charging mode, then we do not need to calibrate the
811 	 * lower capacity.
812 	 */
813 	if (chg_sts == POWER_SUPPLY_STATUS_CHARGING)
814 		return;
815 
816 	if ((ocv > data->cap_table[0].ocv && cap < 100) || cap > 100) {
817 		/*
818 		 * If current OCV value is larger than the max OCV value in
819 		 * OCV table, or the current capacity is larger than 100,
820 		 * we should force the inititial capacity to 100.
821 		 */
822 		sc27xx_fgu_adjust_cap(data, 100);
823 	} else if (ocv <= data->cap_table[data->table_len - 1].ocv) {
824 		/*
825 		 * If current OCV value is leass than the minimum OCV value in
826 		 * OCV table, we should force the inititial capacity to 0.
827 		 */
828 		sc27xx_fgu_adjust_cap(data, 0);
829 	} else if ((ocv > data->cap_table[data->table_len - 1].ocv && cap <= 0) ||
830 		   (ocv > data->min_volt && cap <= data->alarm_cap)) {
831 		/*
832 		 * If current OCV value is not matchable with current capacity,
833 		 * we should re-calculate current capacity by looking up the
834 		 * OCV table.
835 		 */
836 		int cur_cap = power_supply_ocv2cap_simple(data->cap_table,
837 							  data->table_len, ocv);
838 
839 		sc27xx_fgu_adjust_cap(data, cur_cap);
840 	} else if (ocv <= data->min_volt) {
841 		/*
842 		 * If current OCV value is less than the low alarm voltage, but
843 		 * current capacity is larger than the alarm capacity, we should
844 		 * adjust the inititial capacity to alarm capacity.
845 		 */
846 		if (cap > data->alarm_cap) {
847 			sc27xx_fgu_adjust_cap(data, data->alarm_cap);
848 		} else {
849 			int cur_cap;
850 
851 			/*
852 			 * If current capacity is equal with 0 or less than 0
853 			 * (some error occurs), we should adjust inititial
854 			 * capacity to the capacity corresponding to current OCV
855 			 * value.
856 			 */
857 			cur_cap = power_supply_ocv2cap_simple(data->cap_table,
858 							      data->table_len,
859 							      ocv);
860 			sc27xx_fgu_adjust_cap(data, cur_cap);
861 		}
862 
863 		if (!int_mode)
864 			return;
865 
866 		/*
867 		 * After adjusting the battery capacity, we should set the
868 		 * lowest alarm voltage instead.
869 		 */
870 		data->min_volt = data->cap_table[data->table_len - 1].ocv;
871 		data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
872 							      data->table_len,
873 							      data->min_volt);
874 
875 		adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
876 		regmap_update_bits(data->regmap,
877 				   data->base + SC27XX_FGU_LOW_OVERLOAD,
878 				   SC27XX_FGU_LOW_OVERLOAD_MASK, adc);
879 	}
880 }
881 
882 static irqreturn_t sc27xx_fgu_interrupt(int irq, void *dev_id)
883 {
884 	struct sc27xx_fgu_data *data = dev_id;
885 	int ret, cap;
886 	u32 status;
887 
888 	mutex_lock(&data->lock);
889 
890 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_INT_STS,
891 			  &status);
892 	if (ret)
893 		goto out;
894 
895 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
896 				 status, status);
897 	if (ret)
898 		goto out;
899 
900 	/*
901 	 * When low overload voltage interrupt happens, we should calibrate the
902 	 * battery capacity in lower voltage stage.
903 	 */
904 	if (!(status & SC27XX_FGU_LOW_OVERLOAD_INT))
905 		goto out;
906 
907 	ret = sc27xx_fgu_get_capacity(data, &cap);
908 	if (ret)
909 		goto out;
910 
911 	sc27xx_fgu_capacity_calibration(data, cap, true);
912 
913 out:
914 	mutex_unlock(&data->lock);
915 
916 	power_supply_changed(data->battery);
917 	return IRQ_HANDLED;
918 }
919 
920 static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
921 {
922 	struct sc27xx_fgu_data *data = dev_id;
923 	int state;
924 
925 	mutex_lock(&data->lock);
926 
927 	state = gpiod_get_value_cansleep(data->gpiod);
928 	if (state < 0) {
929 		dev_err(data->dev, "failed to get gpio state\n");
930 		mutex_unlock(&data->lock);
931 		return IRQ_RETVAL(state);
932 	}
933 
934 	data->bat_present = !!state;
935 
936 	mutex_unlock(&data->lock);
937 
938 	power_supply_changed(data->battery);
939 	return IRQ_HANDLED;
940 }
941 
942 static void sc27xx_fgu_disable(void *_data)
943 {
944 	struct sc27xx_fgu_data *data = _data;
945 
946 	regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
947 	regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
948 }
949 
950 static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
951 {
952 	/*
953 	 * Get current capacity (mAh) = battery total capacity (mAh) *
954 	 * current capacity percent (capacity / 100).
955 	 */
956 	int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
957 
958 	/*
959 	 * Convert current capacity (mAh) to coulomb counter according to the
960 	 * formula: 1 mAh =3.6 coulomb.
961 	 */
962 	return DIV_ROUND_CLOSEST(cur_cap * 36 * data->cur_1000ma_adc * SC27XX_FGU_SAMPLE_HZ, 10);
963 }
964 
965 static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data)
966 {
967 	struct nvmem_cell *cell;
968 	int calib_data, cal_4200mv;
969 	void *buf;
970 	size_t len;
971 
972 	cell = nvmem_cell_get(data->dev, "fgu_calib");
973 	if (IS_ERR(cell))
974 		return PTR_ERR(cell);
975 
976 	buf = nvmem_cell_read(cell, &len);
977 	nvmem_cell_put(cell);
978 
979 	if (IS_ERR(buf))
980 		return PTR_ERR(buf);
981 
982 	memcpy(&calib_data, buf, min(len, sizeof(u32)));
983 
984 	/*
985 	 * Get the ADC value corresponding to 4200 mV from eFuse controller
986 	 * according to below formula. Then convert to ADC values corresponding
987 	 * to 1000 mV and 1000 mA.
988 	 */
989 	cal_4200mv = (calib_data & 0x1ff) + 6963 - 4096 - 256;
990 	data->vol_1000mv_adc = DIV_ROUND_CLOSEST(cal_4200mv * 10, 42);
991 	data->cur_1000ma_adc =
992 		DIV_ROUND_CLOSEST(data->vol_1000mv_adc * 4 * data->calib_resist,
993 				  SC27XX_FGU_IDEAL_RESISTANCE);
994 
995 	kfree(buf);
996 	return 0;
997 }
998 
999 static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
1000 {
1001 	struct power_supply_battery_info info = { };
1002 	struct power_supply_battery_ocv_table *table;
1003 	int ret, delta_clbcnt, alarm_adc;
1004 
1005 	ret = power_supply_get_battery_info(data->battery, &info);
1006 	if (ret) {
1007 		dev_err(data->dev, "failed to get battery information\n");
1008 		return ret;
1009 	}
1010 
1011 	data->total_cap = info.charge_full_design_uah / 1000;
1012 	data->max_volt = info.constant_charge_voltage_max_uv / 1000;
1013 	data->internal_resist = info.factory_internal_resistance_uohm / 1000;
1014 	data->min_volt = info.voltage_min_design_uv;
1015 
1016 	/*
1017 	 * For SC27XX fuel gauge device, we only use one ocv-capacity
1018 	 * table in normal temperature 20 Celsius.
1019 	 */
1020 	table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
1021 	if (!table)
1022 		return -EINVAL;
1023 
1024 	data->cap_table = devm_kmemdup(data->dev, table,
1025 				       data->table_len * sizeof(*table),
1026 				       GFP_KERNEL);
1027 	if (!data->cap_table) {
1028 		power_supply_put_battery_info(data->battery, &info);
1029 		return -ENOMEM;
1030 	}
1031 
1032 	data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
1033 						      data->table_len,
1034 						      data->min_volt);
1035 	if (!data->alarm_cap)
1036 		data->alarm_cap += 1;
1037 
1038 	data->resist_table_len = info.resist_table_size;
1039 	if (data->resist_table_len > 0) {
1040 		data->resist_table = devm_kmemdup(data->dev, info.resist_table,
1041 						  data->resist_table_len *
1042 						  sizeof(struct power_supply_resistance_temp_table),
1043 						  GFP_KERNEL);
1044 		if (!data->resist_table) {
1045 			power_supply_put_battery_info(data->battery, &info);
1046 			return -ENOMEM;
1047 		}
1048 	}
1049 
1050 	power_supply_put_battery_info(data->battery, &info);
1051 
1052 	ret = sc27xx_fgu_calibration(data);
1053 	if (ret)
1054 		return ret;
1055 
1056 	/* Enable the FGU module */
1057 	ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
1058 				 SC27XX_FGU_EN, SC27XX_FGU_EN);
1059 	if (ret) {
1060 		dev_err(data->dev, "failed to enable fgu\n");
1061 		return ret;
1062 	}
1063 
1064 	/* Enable the FGU RTC clock to make it work */
1065 	ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
1066 				 SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
1067 	if (ret) {
1068 		dev_err(data->dev, "failed to enable fgu RTC clock\n");
1069 		goto disable_fgu;
1070 	}
1071 
1072 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
1073 				 SC27XX_FGU_INT_MASK, SC27XX_FGU_INT_MASK);
1074 	if (ret) {
1075 		dev_err(data->dev, "failed to clear interrupt status\n");
1076 		goto disable_clk;
1077 	}
1078 
1079 	/*
1080 	 * Set the voltage low overload threshold, which means when the battery
1081 	 * voltage is lower than this threshold, the controller will generate
1082 	 * one interrupt to notify.
1083 	 */
1084 	alarm_adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
1085 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_LOW_OVERLOAD,
1086 				 SC27XX_FGU_LOW_OVERLOAD_MASK, alarm_adc);
1087 	if (ret) {
1088 		dev_err(data->dev, "failed to set fgu low overload\n");
1089 		goto disable_clk;
1090 	}
1091 
1092 	/*
1093 	 * Set the coulomb counter delta threshold, that means when the coulomb
1094 	 * counter change is multiples of the delta threshold, the controller
1095 	 * will generate one interrupt to notify the users to update the battery
1096 	 * capacity. Now we set the delta threshold as a counter value of 1%
1097 	 * capacity.
1098 	 */
1099 	delta_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, 1);
1100 
1101 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTL,
1102 				 SC27XX_FGU_CLBCNT_MASK, delta_clbcnt);
1103 	if (ret) {
1104 		dev_err(data->dev, "failed to set low delta coulomb counter\n");
1105 		goto disable_clk;
1106 	}
1107 
1108 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTH,
1109 				 SC27XX_FGU_CLBCNT_MASK,
1110 				 delta_clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
1111 	if (ret) {
1112 		dev_err(data->dev, "failed to set high delta coulomb counter\n");
1113 		goto disable_clk;
1114 	}
1115 
1116 	/*
1117 	 * Get the boot battery capacity when system powers on, which is used to
1118 	 * initialize the coulomb counter. After that, we can read the coulomb
1119 	 * counter to measure the battery capacity.
1120 	 */
1121 	ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
1122 	if (ret) {
1123 		dev_err(data->dev, "failed to get boot capacity\n");
1124 		goto disable_clk;
1125 	}
1126 
1127 	/*
1128 	 * Convert battery capacity to the corresponding initial coulomb counter
1129 	 * and set into coulomb counter registers.
1130 	 */
1131 	data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
1132 	ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
1133 	if (ret) {
1134 		dev_err(data->dev, "failed to initialize coulomb counter\n");
1135 		goto disable_clk;
1136 	}
1137 
1138 	return 0;
1139 
1140 disable_clk:
1141 	regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
1142 disable_fgu:
1143 	regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
1144 
1145 	return ret;
1146 }
1147 
1148 static int sc27xx_fgu_probe(struct platform_device *pdev)
1149 {
1150 	struct device *dev = &pdev->dev;
1151 	struct device_node *np = dev->of_node;
1152 	struct power_supply_config fgu_cfg = { };
1153 	struct sc27xx_fgu_data *data;
1154 	int ret, irq;
1155 
1156 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1157 	if (!data)
1158 		return -ENOMEM;
1159 
1160 	data->regmap = dev_get_regmap(dev->parent, NULL);
1161 	if (!data->regmap) {
1162 		dev_err(dev, "failed to get regmap\n");
1163 		return -ENODEV;
1164 	}
1165 
1166 	ret = device_property_read_u32(dev, "reg", &data->base);
1167 	if (ret) {
1168 		dev_err(dev, "failed to get fgu address\n");
1169 		return ret;
1170 	}
1171 
1172 	ret = device_property_read_u32(&pdev->dev,
1173 				       "sprd,calib-resistance-micro-ohms",
1174 				       &data->calib_resist);
1175 	if (ret) {
1176 		dev_err(&pdev->dev,
1177 			"failed to get fgu calibration resistance\n");
1178 		return ret;
1179 	}
1180 
1181 	data->channel = devm_iio_channel_get(dev, "bat-temp");
1182 	if (IS_ERR(data->channel)) {
1183 		dev_err(dev, "failed to get IIO channel\n");
1184 		return PTR_ERR(data->channel);
1185 	}
1186 
1187 	data->charge_chan = devm_iio_channel_get(dev, "charge-vol");
1188 	if (IS_ERR(data->charge_chan)) {
1189 		dev_err(dev, "failed to get charge IIO channel\n");
1190 		return PTR_ERR(data->charge_chan);
1191 	}
1192 
1193 	data->gpiod = devm_gpiod_get(dev, "bat-detect", GPIOD_IN);
1194 	if (IS_ERR(data->gpiod)) {
1195 		dev_err(dev, "failed to get battery detection GPIO\n");
1196 		return PTR_ERR(data->gpiod);
1197 	}
1198 
1199 	ret = gpiod_get_value_cansleep(data->gpiod);
1200 	if (ret < 0) {
1201 		dev_err(dev, "failed to get gpio state\n");
1202 		return ret;
1203 	}
1204 
1205 	data->bat_present = !!ret;
1206 	mutex_init(&data->lock);
1207 	data->dev = dev;
1208 	platform_set_drvdata(pdev, data);
1209 
1210 	fgu_cfg.drv_data = data;
1211 	fgu_cfg.of_node = np;
1212 	data->battery = devm_power_supply_register(dev, &sc27xx_fgu_desc,
1213 						   &fgu_cfg);
1214 	if (IS_ERR(data->battery)) {
1215 		dev_err(dev, "failed to register power supply\n");
1216 		return PTR_ERR(data->battery);
1217 	}
1218 
1219 	ret = sc27xx_fgu_hw_init(data);
1220 	if (ret) {
1221 		dev_err(dev, "failed to initialize fgu hardware\n");
1222 		return ret;
1223 	}
1224 
1225 	ret = devm_add_action_or_reset(dev, sc27xx_fgu_disable, data);
1226 	if (ret) {
1227 		dev_err(dev, "failed to add fgu disable action\n");
1228 		return ret;
1229 	}
1230 
1231 	irq = platform_get_irq(pdev, 0);
1232 	if (irq < 0) {
1233 		dev_err(dev, "no irq resource specified\n");
1234 		return irq;
1235 	}
1236 
1237 	ret = devm_request_threaded_irq(data->dev, irq, NULL,
1238 					sc27xx_fgu_interrupt,
1239 					IRQF_NO_SUSPEND | IRQF_ONESHOT,
1240 					pdev->name, data);
1241 	if (ret) {
1242 		dev_err(data->dev, "failed to request fgu IRQ\n");
1243 		return ret;
1244 	}
1245 
1246 	irq = gpiod_to_irq(data->gpiod);
1247 	if (irq < 0) {
1248 		dev_err(dev, "failed to translate GPIO to IRQ\n");
1249 		return irq;
1250 	}
1251 
1252 	ret = devm_request_threaded_irq(dev, irq, NULL,
1253 					sc27xx_fgu_bat_detection,
1254 					IRQF_ONESHOT | IRQF_TRIGGER_RISING |
1255 					IRQF_TRIGGER_FALLING,
1256 					pdev->name, data);
1257 	if (ret) {
1258 		dev_err(dev, "failed to request IRQ\n");
1259 		return ret;
1260 	}
1261 
1262 	return 0;
1263 }
1264 
1265 #ifdef CONFIG_PM_SLEEP
1266 static int sc27xx_fgu_resume(struct device *dev)
1267 {
1268 	struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1269 	int ret;
1270 
1271 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1272 				 SC27XX_FGU_LOW_OVERLOAD_INT |
1273 				 SC27XX_FGU_CLBCNT_DELTA_INT, 0);
1274 	if (ret) {
1275 		dev_err(data->dev, "failed to disable fgu interrupts\n");
1276 		return ret;
1277 	}
1278 
1279 	return 0;
1280 }
1281 
1282 static int sc27xx_fgu_suspend(struct device *dev)
1283 {
1284 	struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1285 	int ret, status, ocv;
1286 
1287 	ret = sc27xx_fgu_get_status(data, &status);
1288 	if (ret)
1289 		return ret;
1290 
1291 	/*
1292 	 * If we are charging, then no need to enable the FGU interrupts to
1293 	 * adjust the battery capacity.
1294 	 */
1295 	if (status != POWER_SUPPLY_STATUS_NOT_CHARGING &&
1296 	    status != POWER_SUPPLY_STATUS_DISCHARGING)
1297 		return 0;
1298 
1299 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1300 				 SC27XX_FGU_LOW_OVERLOAD_INT,
1301 				 SC27XX_FGU_LOW_OVERLOAD_INT);
1302 	if (ret) {
1303 		dev_err(data->dev, "failed to enable low voltage interrupt\n");
1304 		return ret;
1305 	}
1306 
1307 	ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
1308 	if (ret)
1309 		goto disable_int;
1310 
1311 	/*
1312 	 * If current OCV is less than the minimum voltage, we should enable the
1313 	 * coulomb counter threshold interrupt to notify events to adjust the
1314 	 * battery capacity.
1315 	 */
1316 	if (ocv < data->min_volt) {
1317 		ret = regmap_update_bits(data->regmap,
1318 					 data->base + SC27XX_FGU_INT_EN,
1319 					 SC27XX_FGU_CLBCNT_DELTA_INT,
1320 					 SC27XX_FGU_CLBCNT_DELTA_INT);
1321 		if (ret) {
1322 			dev_err(data->dev,
1323 				"failed to enable coulomb threshold int\n");
1324 			goto disable_int;
1325 		}
1326 	}
1327 
1328 	return 0;
1329 
1330 disable_int:
1331 	regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1332 			   SC27XX_FGU_LOW_OVERLOAD_INT, 0);
1333 	return ret;
1334 }
1335 #endif
1336 
1337 static const struct dev_pm_ops sc27xx_fgu_pm_ops = {
1338 	SET_SYSTEM_SLEEP_PM_OPS(sc27xx_fgu_suspend, sc27xx_fgu_resume)
1339 };
1340 
1341 static const struct of_device_id sc27xx_fgu_of_match[] = {
1342 	{ .compatible = "sprd,sc2731-fgu", },
1343 	{ }
1344 };
1345 MODULE_DEVICE_TABLE(of, sc27xx_fgu_of_match);
1346 
1347 static struct platform_driver sc27xx_fgu_driver = {
1348 	.probe = sc27xx_fgu_probe,
1349 	.driver = {
1350 		.name = "sc27xx-fgu",
1351 		.of_match_table = sc27xx_fgu_of_match,
1352 		.pm = &sc27xx_fgu_pm_ops,
1353 	}
1354 };
1355 
1356 module_platform_driver(sc27xx_fgu_driver);
1357 
1358 MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver");
1359 MODULE_LICENSE("GPL v2");
1360