xref: /linux/drivers/power/supply/sc27xx_fuel_gauge.c (revision 448ecd5771e255629bef0fb16c9b78c4bbd7bd56)
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 
sc27xx_fgu_adc_to_current(struct sc27xx_fgu_data * data,s64 adc)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 
sc27xx_fgu_adc_to_voltage(struct sc27xx_fgu_data * data,s64 adc)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 
sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data * data,int vol)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 
sc27xx_fgu_is_first_poweron(struct sc27xx_fgu_data * data)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 
sc27xx_fgu_save_boot_mode(struct sc27xx_fgu_data * data,int boot_mode)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 
sc27xx_fgu_save_last_cap(struct sc27xx_fgu_data * data,int cap)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 
sc27xx_fgu_read_last_cap(struct sc27xx_fgu_data * data,int * cap)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  */
sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data * data,int * cap)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 
sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data * data,int clbcnt)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 
sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data * data,int * clb_cnt)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 
sc27xx_fgu_get_vol_now(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_cur_now(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_capacity(struct sc27xx_fgu_data * data,int * cap)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 
sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_current(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_charge_vol(struct sc27xx_fgu_data * data,int * val)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 
sc27xx_fgu_get_temp(struct sc27xx_fgu_data * data,int * temp)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 
sc27xx_fgu_get_health(struct sc27xx_fgu_data * data,int * health)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 
sc27xx_fgu_get_status(struct sc27xx_fgu_data * data,int * status)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 
sc27xx_fgu_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)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 
sc27xx_fgu_set_property(struct power_supply * psy,enum power_supply_property psp,const union power_supply_propval * val)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 
sc27xx_fgu_property_is_writeable(struct power_supply * psy,enum power_supply_property psp)736 static int sc27xx_fgu_property_is_writeable(struct power_supply *psy,
737 					    enum power_supply_property psp)
738 {
739 	return psp == POWER_SUPPLY_PROP_CAPACITY ||
740 		psp == POWER_SUPPLY_PROP_CALIBRATE ||
741 		psp == POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
742 }
743 
744 static enum power_supply_property sc27xx_fgu_props[] = {
745 	POWER_SUPPLY_PROP_STATUS,
746 	POWER_SUPPLY_PROP_HEALTH,
747 	POWER_SUPPLY_PROP_PRESENT,
748 	POWER_SUPPLY_PROP_TEMP,
749 	POWER_SUPPLY_PROP_TECHNOLOGY,
750 	POWER_SUPPLY_PROP_CAPACITY,
751 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
752 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
753 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
754 	POWER_SUPPLY_PROP_VOLTAGE_BOOT,
755 	POWER_SUPPLY_PROP_CURRENT_NOW,
756 	POWER_SUPPLY_PROP_CURRENT_AVG,
757 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
758 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
759 	POWER_SUPPLY_PROP_CALIBRATE,
760 	POWER_SUPPLY_PROP_CHARGE_NOW
761 };
762 
763 static const struct power_supply_desc sc27xx_fgu_desc = {
764 	.name			= "sc27xx-fgu",
765 	.type			= POWER_SUPPLY_TYPE_BATTERY,
766 	.properties		= sc27xx_fgu_props,
767 	.num_properties		= ARRAY_SIZE(sc27xx_fgu_props),
768 	.get_property		= sc27xx_fgu_get_property,
769 	.set_property		= sc27xx_fgu_set_property,
770 	.external_power_changed	= power_supply_changed,
771 	.property_is_writeable	= sc27xx_fgu_property_is_writeable,
772 	.no_thermal		= true,
773 };
774 
sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data * data,int cap)775 static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap)
776 {
777 	int ret;
778 
779 	data->init_cap = cap;
780 	ret = sc27xx_fgu_get_clbcnt(data, &data->init_clbcnt);
781 	if (ret)
782 		dev_err(data->dev, "failed to get init coulomb counter\n");
783 }
784 
sc27xx_fgu_capacity_calibration(struct sc27xx_fgu_data * data,int cap,bool int_mode)785 static void sc27xx_fgu_capacity_calibration(struct sc27xx_fgu_data *data,
786 					    int cap, bool int_mode)
787 {
788 	int ret, ocv, chg_sts, adc;
789 
790 	ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
791 	if (ret) {
792 		dev_err(data->dev, "get battery ocv error.\n");
793 		return;
794 	}
795 
796 	ret = sc27xx_fgu_get_status(data, &chg_sts);
797 	if (ret) {
798 		dev_err(data->dev, "get charger status error.\n");
799 		return;
800 	}
801 
802 	/*
803 	 * If we are in charging mode, then we do not need to calibrate the
804 	 * lower capacity.
805 	 */
806 	if (chg_sts == POWER_SUPPLY_STATUS_CHARGING)
807 		return;
808 
809 	if ((ocv > data->cap_table[0].ocv && cap < 100) || cap > 100) {
810 		/*
811 		 * If current OCV value is larger than the max OCV value in
812 		 * OCV table, or the current capacity is larger than 100,
813 		 * we should force the inititial capacity to 100.
814 		 */
815 		sc27xx_fgu_adjust_cap(data, 100);
816 	} else if (ocv <= data->cap_table[data->table_len - 1].ocv) {
817 		/*
818 		 * If current OCV value is leass than the minimum OCV value in
819 		 * OCV table, we should force the inititial capacity to 0.
820 		 */
821 		sc27xx_fgu_adjust_cap(data, 0);
822 	} else if ((ocv > data->cap_table[data->table_len - 1].ocv && cap <= 0) ||
823 		   (ocv > data->min_volt && cap <= data->alarm_cap)) {
824 		/*
825 		 * If current OCV value is not matchable with current capacity,
826 		 * we should re-calculate current capacity by looking up the
827 		 * OCV table.
828 		 */
829 		int cur_cap = power_supply_ocv2cap_simple(data->cap_table,
830 							  data->table_len, ocv);
831 
832 		sc27xx_fgu_adjust_cap(data, cur_cap);
833 	} else if (ocv <= data->min_volt) {
834 		/*
835 		 * If current OCV value is less than the low alarm voltage, but
836 		 * current capacity is larger than the alarm capacity, we should
837 		 * adjust the inititial capacity to alarm capacity.
838 		 */
839 		if (cap > data->alarm_cap) {
840 			sc27xx_fgu_adjust_cap(data, data->alarm_cap);
841 		} else {
842 			int cur_cap;
843 
844 			/*
845 			 * If current capacity is equal with 0 or less than 0
846 			 * (some error occurs), we should adjust inititial
847 			 * capacity to the capacity corresponding to current OCV
848 			 * value.
849 			 */
850 			cur_cap = power_supply_ocv2cap_simple(data->cap_table,
851 							      data->table_len,
852 							      ocv);
853 			sc27xx_fgu_adjust_cap(data, cur_cap);
854 		}
855 
856 		if (!int_mode)
857 			return;
858 
859 		/*
860 		 * After adjusting the battery capacity, we should set the
861 		 * lowest alarm voltage instead.
862 		 */
863 		data->min_volt = data->cap_table[data->table_len - 1].ocv;
864 		data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
865 							      data->table_len,
866 							      data->min_volt);
867 
868 		adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
869 		regmap_update_bits(data->regmap,
870 				   data->base + SC27XX_FGU_LOW_OVERLOAD,
871 				   SC27XX_FGU_LOW_OVERLOAD_MASK, adc);
872 	}
873 }
874 
sc27xx_fgu_interrupt(int irq,void * dev_id)875 static irqreturn_t sc27xx_fgu_interrupt(int irq, void *dev_id)
876 {
877 	struct sc27xx_fgu_data *data = dev_id;
878 	int ret, cap;
879 	u32 status;
880 
881 	mutex_lock(&data->lock);
882 
883 	ret = regmap_read(data->regmap, data->base + SC27XX_FGU_INT_STS,
884 			  &status);
885 	if (ret)
886 		goto out;
887 
888 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
889 				 status, status);
890 	if (ret)
891 		goto out;
892 
893 	/*
894 	 * When low overload voltage interrupt happens, we should calibrate the
895 	 * battery capacity in lower voltage stage.
896 	 */
897 	if (!(status & SC27XX_FGU_LOW_OVERLOAD_INT))
898 		goto out;
899 
900 	ret = sc27xx_fgu_get_capacity(data, &cap);
901 	if (ret)
902 		goto out;
903 
904 	sc27xx_fgu_capacity_calibration(data, cap, true);
905 
906 out:
907 	mutex_unlock(&data->lock);
908 
909 	power_supply_changed(data->battery);
910 	return IRQ_HANDLED;
911 }
912 
sc27xx_fgu_bat_detection(int irq,void * dev_id)913 static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
914 {
915 	struct sc27xx_fgu_data *data = dev_id;
916 	int state;
917 
918 	mutex_lock(&data->lock);
919 
920 	state = gpiod_get_value_cansleep(data->gpiod);
921 	if (state < 0) {
922 		dev_err(data->dev, "failed to get gpio state\n");
923 		mutex_unlock(&data->lock);
924 		return IRQ_RETVAL(state);
925 	}
926 
927 	data->bat_present = !!state;
928 
929 	mutex_unlock(&data->lock);
930 
931 	power_supply_changed(data->battery);
932 	return IRQ_HANDLED;
933 }
934 
sc27xx_fgu_disable(void * _data)935 static void sc27xx_fgu_disable(void *_data)
936 {
937 	struct sc27xx_fgu_data *data = _data;
938 
939 	regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
940 	regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
941 }
942 
sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data * data,int capacity)943 static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
944 {
945 	/*
946 	 * Get current capacity (mAh) = battery total capacity (mAh) *
947 	 * current capacity percent (capacity / 100).
948 	 */
949 	int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
950 
951 	/*
952 	 * Convert current capacity (mAh) to coulomb counter according to the
953 	 * formula: 1 mAh =3.6 coulomb.
954 	 */
955 	return DIV_ROUND_CLOSEST(cur_cap * 36 * data->cur_1000ma_adc * SC27XX_FGU_SAMPLE_HZ, 10);
956 }
957 
sc27xx_fgu_calibration(struct sc27xx_fgu_data * data)958 static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data)
959 {
960 	struct nvmem_cell *cell;
961 	int calib_data, cal_4200mv;
962 	void *buf;
963 	size_t len;
964 
965 	cell = nvmem_cell_get(data->dev, "fgu_calib");
966 	if (IS_ERR(cell))
967 		return PTR_ERR(cell);
968 
969 	buf = nvmem_cell_read(cell, &len);
970 	nvmem_cell_put(cell);
971 
972 	if (IS_ERR(buf))
973 		return PTR_ERR(buf);
974 
975 	memcpy(&calib_data, buf, min(len, sizeof(u32)));
976 
977 	/*
978 	 * Get the ADC value corresponding to 4200 mV from eFuse controller
979 	 * according to below formula. Then convert to ADC values corresponding
980 	 * to 1000 mV and 1000 mA.
981 	 */
982 	cal_4200mv = (calib_data & 0x1ff) + 6963 - 4096 - 256;
983 	data->vol_1000mv_adc = DIV_ROUND_CLOSEST(cal_4200mv * 10, 42);
984 	data->cur_1000ma_adc =
985 		DIV_ROUND_CLOSEST(data->vol_1000mv_adc * 4 * data->calib_resist,
986 				  SC27XX_FGU_IDEAL_RESISTANCE);
987 
988 	kfree(buf);
989 	return 0;
990 }
991 
sc27xx_fgu_hw_init(struct sc27xx_fgu_data * data)992 static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
993 {
994 	struct power_supply_battery_info *info;
995 	const struct power_supply_battery_ocv_table *table;
996 	int ret, delta_clbcnt, alarm_adc;
997 
998 	ret = power_supply_get_battery_info(data->battery, &info);
999 	if (ret) {
1000 		dev_err(data->dev, "failed to get battery information\n");
1001 		return ret;
1002 	}
1003 
1004 	data->total_cap = info->charge_full_design_uah / 1000;
1005 	data->max_volt = info->constant_charge_voltage_max_uv / 1000;
1006 	data->internal_resist = info->factory_internal_resistance_uohm / 1000;
1007 	data->min_volt = info->voltage_min_design_uv;
1008 
1009 	/*
1010 	 * For SC27XX fuel gauge device, we only use one ocv-capacity
1011 	 * table in normal temperature 20 Celsius.
1012 	 */
1013 	table = power_supply_find_ocv2cap_table(info, 20, &data->table_len);
1014 	if (!table)
1015 		return -EINVAL;
1016 
1017 	data->cap_table = devm_kmemdup(data->dev, table,
1018 				       data->table_len * sizeof(*table),
1019 				       GFP_KERNEL);
1020 	if (!data->cap_table) {
1021 		power_supply_put_battery_info(data->battery, info);
1022 		return -ENOMEM;
1023 	}
1024 
1025 	data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
1026 						      data->table_len,
1027 						      data->min_volt);
1028 	if (!data->alarm_cap)
1029 		data->alarm_cap += 1;
1030 
1031 	data->resist_table_len = info->resist_table_size;
1032 	if (data->resist_table_len > 0) {
1033 		data->resist_table = devm_kmemdup(data->dev, info->resist_table,
1034 						  data->resist_table_len *
1035 						  sizeof(struct power_supply_resistance_temp_table),
1036 						  GFP_KERNEL);
1037 		if (!data->resist_table) {
1038 			power_supply_put_battery_info(data->battery, info);
1039 			return -ENOMEM;
1040 		}
1041 	}
1042 
1043 	power_supply_put_battery_info(data->battery, info);
1044 
1045 	ret = sc27xx_fgu_calibration(data);
1046 	if (ret)
1047 		return ret;
1048 
1049 	/* Enable the FGU module */
1050 	ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
1051 				 SC27XX_FGU_EN, SC27XX_FGU_EN);
1052 	if (ret) {
1053 		dev_err(data->dev, "failed to enable fgu\n");
1054 		return ret;
1055 	}
1056 
1057 	/* Enable the FGU RTC clock to make it work */
1058 	ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
1059 				 SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
1060 	if (ret) {
1061 		dev_err(data->dev, "failed to enable fgu RTC clock\n");
1062 		goto disable_fgu;
1063 	}
1064 
1065 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
1066 				 SC27XX_FGU_INT_MASK, SC27XX_FGU_INT_MASK);
1067 	if (ret) {
1068 		dev_err(data->dev, "failed to clear interrupt status\n");
1069 		goto disable_clk;
1070 	}
1071 
1072 	/*
1073 	 * Set the voltage low overload threshold, which means when the battery
1074 	 * voltage is lower than this threshold, the controller will generate
1075 	 * one interrupt to notify.
1076 	 */
1077 	alarm_adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
1078 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_LOW_OVERLOAD,
1079 				 SC27XX_FGU_LOW_OVERLOAD_MASK, alarm_adc);
1080 	if (ret) {
1081 		dev_err(data->dev, "failed to set fgu low overload\n");
1082 		goto disable_clk;
1083 	}
1084 
1085 	/*
1086 	 * Set the coulomb counter delta threshold, that means when the coulomb
1087 	 * counter change is multiples of the delta threshold, the controller
1088 	 * will generate one interrupt to notify the users to update the battery
1089 	 * capacity. Now we set the delta threshold as a counter value of 1%
1090 	 * capacity.
1091 	 */
1092 	delta_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, 1);
1093 
1094 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTL,
1095 				 SC27XX_FGU_CLBCNT_MASK, delta_clbcnt);
1096 	if (ret) {
1097 		dev_err(data->dev, "failed to set low delta coulomb counter\n");
1098 		goto disable_clk;
1099 	}
1100 
1101 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTH,
1102 				 SC27XX_FGU_CLBCNT_MASK,
1103 				 delta_clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
1104 	if (ret) {
1105 		dev_err(data->dev, "failed to set high delta coulomb counter\n");
1106 		goto disable_clk;
1107 	}
1108 
1109 	/*
1110 	 * Get the boot battery capacity when system powers on, which is used to
1111 	 * initialize the coulomb counter. After that, we can read the coulomb
1112 	 * counter to measure the battery capacity.
1113 	 */
1114 	ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
1115 	if (ret) {
1116 		dev_err(data->dev, "failed to get boot capacity\n");
1117 		goto disable_clk;
1118 	}
1119 
1120 	/*
1121 	 * Convert battery capacity to the corresponding initial coulomb counter
1122 	 * and set into coulomb counter registers.
1123 	 */
1124 	data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
1125 	ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
1126 	if (ret) {
1127 		dev_err(data->dev, "failed to initialize coulomb counter\n");
1128 		goto disable_clk;
1129 	}
1130 
1131 	return 0;
1132 
1133 disable_clk:
1134 	regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
1135 disable_fgu:
1136 	regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
1137 
1138 	return ret;
1139 }
1140 
sc27xx_fgu_probe(struct platform_device * pdev)1141 static int sc27xx_fgu_probe(struct platform_device *pdev)
1142 {
1143 	struct device *dev = &pdev->dev;
1144 	struct device_node *np = dev->of_node;
1145 	struct power_supply_config fgu_cfg = { };
1146 	struct sc27xx_fgu_data *data;
1147 	int ret, irq;
1148 
1149 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1150 	if (!data)
1151 		return -ENOMEM;
1152 
1153 	data->regmap = dev_get_regmap(dev->parent, NULL);
1154 	if (!data->regmap) {
1155 		dev_err(dev, "failed to get regmap\n");
1156 		return -ENODEV;
1157 	}
1158 
1159 	ret = device_property_read_u32(dev, "reg", &data->base);
1160 	if (ret) {
1161 		dev_err(dev, "failed to get fgu address\n");
1162 		return ret;
1163 	}
1164 
1165 	ret = device_property_read_u32(&pdev->dev,
1166 				       "sprd,calib-resistance-micro-ohms",
1167 				       &data->calib_resist);
1168 	if (ret) {
1169 		dev_err(&pdev->dev,
1170 			"failed to get fgu calibration resistance\n");
1171 		return ret;
1172 	}
1173 
1174 	data->channel = devm_iio_channel_get(dev, "bat-temp");
1175 	if (IS_ERR(data->channel)) {
1176 		dev_err(dev, "failed to get IIO channel\n");
1177 		return PTR_ERR(data->channel);
1178 	}
1179 
1180 	data->charge_chan = devm_iio_channel_get(dev, "charge-vol");
1181 	if (IS_ERR(data->charge_chan)) {
1182 		dev_err(dev, "failed to get charge IIO channel\n");
1183 		return PTR_ERR(data->charge_chan);
1184 	}
1185 
1186 	data->gpiod = devm_gpiod_get(dev, "battery-detect", GPIOD_IN);
1187 	if (IS_ERR(data->gpiod)) {
1188 		data->gpiod = devm_gpiod_get(dev, "bat-detect", GPIOD_IN);
1189 		if (IS_ERR(data->gpiod)) {
1190 			dev_err(dev, "failed to get battery detection GPIO\n");
1191 			return PTR_ERR(data->gpiod);
1192 		}
1193 		dev_warn(dev, "bat-detect is deprecated, please use battery-detect\n");
1194 	}
1195 
1196 	ret = gpiod_get_value_cansleep(data->gpiod);
1197 	if (ret < 0) {
1198 		dev_err(dev, "failed to get gpio state\n");
1199 		return ret;
1200 	}
1201 
1202 	data->bat_present = !!ret;
1203 	mutex_init(&data->lock);
1204 	data->dev = dev;
1205 	platform_set_drvdata(pdev, data);
1206 
1207 	fgu_cfg.drv_data = data;
1208 	fgu_cfg.of_node = np;
1209 	data->battery = devm_power_supply_register(dev, &sc27xx_fgu_desc,
1210 						   &fgu_cfg);
1211 	if (IS_ERR(data->battery)) {
1212 		dev_err(dev, "failed to register power supply\n");
1213 		return PTR_ERR(data->battery);
1214 	}
1215 
1216 	ret = sc27xx_fgu_hw_init(data);
1217 	if (ret) {
1218 		dev_err(dev, "failed to initialize fgu hardware\n");
1219 		return ret;
1220 	}
1221 
1222 	ret = devm_add_action_or_reset(dev, sc27xx_fgu_disable, data);
1223 	if (ret) {
1224 		dev_err(dev, "failed to add fgu disable action\n");
1225 		return ret;
1226 	}
1227 
1228 	irq = platform_get_irq(pdev, 0);
1229 	if (irq < 0)
1230 		return irq;
1231 
1232 	ret = devm_request_threaded_irq(data->dev, irq, NULL,
1233 					sc27xx_fgu_interrupt,
1234 					IRQF_NO_SUSPEND | IRQF_ONESHOT,
1235 					pdev->name, data);
1236 	if (ret) {
1237 		dev_err(data->dev, "failed to request fgu IRQ\n");
1238 		return ret;
1239 	}
1240 
1241 	irq = gpiod_to_irq(data->gpiod);
1242 	if (irq < 0) {
1243 		dev_err(dev, "failed to translate GPIO to IRQ\n");
1244 		return irq;
1245 	}
1246 
1247 	ret = devm_request_threaded_irq(dev, irq, NULL,
1248 					sc27xx_fgu_bat_detection,
1249 					IRQF_ONESHOT | IRQF_TRIGGER_RISING |
1250 					IRQF_TRIGGER_FALLING,
1251 					pdev->name, data);
1252 	if (ret) {
1253 		dev_err(dev, "failed to request IRQ\n");
1254 		return ret;
1255 	}
1256 
1257 	return 0;
1258 }
1259 
1260 #ifdef CONFIG_PM_SLEEP
sc27xx_fgu_resume(struct device * dev)1261 static int sc27xx_fgu_resume(struct device *dev)
1262 {
1263 	struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1264 	int ret;
1265 
1266 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1267 				 SC27XX_FGU_LOW_OVERLOAD_INT |
1268 				 SC27XX_FGU_CLBCNT_DELTA_INT, 0);
1269 	if (ret) {
1270 		dev_err(data->dev, "failed to disable fgu interrupts\n");
1271 		return ret;
1272 	}
1273 
1274 	return 0;
1275 }
1276 
sc27xx_fgu_suspend(struct device * dev)1277 static int sc27xx_fgu_suspend(struct device *dev)
1278 {
1279 	struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1280 	int ret, status, ocv;
1281 
1282 	ret = sc27xx_fgu_get_status(data, &status);
1283 	if (ret)
1284 		return ret;
1285 
1286 	/*
1287 	 * If we are charging, then no need to enable the FGU interrupts to
1288 	 * adjust the battery capacity.
1289 	 */
1290 	if (status != POWER_SUPPLY_STATUS_NOT_CHARGING &&
1291 	    status != POWER_SUPPLY_STATUS_DISCHARGING)
1292 		return 0;
1293 
1294 	ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1295 				 SC27XX_FGU_LOW_OVERLOAD_INT,
1296 				 SC27XX_FGU_LOW_OVERLOAD_INT);
1297 	if (ret) {
1298 		dev_err(data->dev, "failed to enable low voltage interrupt\n");
1299 		return ret;
1300 	}
1301 
1302 	ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
1303 	if (ret)
1304 		goto disable_int;
1305 
1306 	/*
1307 	 * If current OCV is less than the minimum voltage, we should enable the
1308 	 * coulomb counter threshold interrupt to notify events to adjust the
1309 	 * battery capacity.
1310 	 */
1311 	if (ocv < data->min_volt) {
1312 		ret = regmap_update_bits(data->regmap,
1313 					 data->base + SC27XX_FGU_INT_EN,
1314 					 SC27XX_FGU_CLBCNT_DELTA_INT,
1315 					 SC27XX_FGU_CLBCNT_DELTA_INT);
1316 		if (ret) {
1317 			dev_err(data->dev,
1318 				"failed to enable coulomb threshold int\n");
1319 			goto disable_int;
1320 		}
1321 	}
1322 
1323 	return 0;
1324 
1325 disable_int:
1326 	regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1327 			   SC27XX_FGU_LOW_OVERLOAD_INT, 0);
1328 	return ret;
1329 }
1330 #endif
1331 
1332 static const struct dev_pm_ops sc27xx_fgu_pm_ops = {
1333 	SET_SYSTEM_SLEEP_PM_OPS(sc27xx_fgu_suspend, sc27xx_fgu_resume)
1334 };
1335 
1336 static const struct of_device_id sc27xx_fgu_of_match[] = {
1337 	{ .compatible = "sprd,sc2731-fgu", },
1338 	{ }
1339 };
1340 MODULE_DEVICE_TABLE(of, sc27xx_fgu_of_match);
1341 
1342 static struct platform_driver sc27xx_fgu_driver = {
1343 	.probe = sc27xx_fgu_probe,
1344 	.driver = {
1345 		.name = "sc27xx-fgu",
1346 		.of_match_table = sc27xx_fgu_of_match,
1347 		.pm = &sc27xx_fgu_pm_ops,
1348 	}
1349 };
1350 
1351 module_platform_driver(sc27xx_fgu_driver);
1352 
1353 MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver");
1354 MODULE_LICENSE("GPL v2");
1355