1 /*
2  * TI BQ24257 charger driver
3  *
4  * Copyright (C) 2015 Intel Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * Datasheets:
17  * http://www.ti.com/product/bq24250
18  * http://www.ti.com/product/bq24251
19  * http://www.ti.com/product/bq24257
20  */
21 
22 #include <linux/module.h>
23 #include <linux/i2c.h>
24 #include <linux/power_supply.h>
25 #include <linux/regmap.h>
26 #include <linux/types.h>
27 #include <linux/gpio/consumer.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 
31 #include <linux/acpi.h>
32 #include <linux/of.h>
33 
34 #define BQ24257_REG_1			0x00
35 #define BQ24257_REG_2			0x01
36 #define BQ24257_REG_3			0x02
37 #define BQ24257_REG_4			0x03
38 #define BQ24257_REG_5			0x04
39 #define BQ24257_REG_6			0x05
40 #define BQ24257_REG_7			0x06
41 
42 #define BQ24257_MANUFACTURER		"Texas Instruments"
43 #define BQ24257_PG_GPIO			"pg"
44 
45 #define BQ24257_ILIM_SET_DELAY		1000	/* msec */
46 
47 /*
48  * When adding support for new devices make sure that enum bq2425x_chip and
49  * bq2425x_chip_name[] always stay in sync!
50  */
51 enum bq2425x_chip {
52 	BQ24250,
53 	BQ24251,
54 	BQ24257,
55 };
56 
57 static const char *const bq2425x_chip_name[] = {
58 	"bq24250",
59 	"bq24251",
60 	"bq24257",
61 };
62 
63 enum bq24257_fields {
64 	F_WD_FAULT, F_WD_EN, F_STAT, F_FAULT,			    /* REG 1 */
65 	F_RESET, F_IILIMIT, F_EN_STAT, F_EN_TERM, F_CE, F_HZ_MODE,  /* REG 2 */
66 	F_VBAT, F_USB_DET,					    /* REG 3 */
67 	F_ICHG, F_ITERM,					    /* REG 4 */
68 	F_LOOP_STATUS, F_LOW_CHG, F_DPDM_EN, F_CE_STATUS, F_VINDPM, /* REG 5 */
69 	F_X2_TMR_EN, F_TMR, F_SYSOFF, F_TS_EN, F_TS_STAT,	    /* REG 6 */
70 	F_VOVP, F_CLR_VDP, F_FORCE_BATDET, F_FORCE_PTM,		    /* REG 7 */
71 
72 	F_MAX_FIELDS
73 };
74 
75 /* initial field values, converted from uV/uA */
76 struct bq24257_init_data {
77 	u8 ichg;	/* charge current      */
78 	u8 vbat;	/* regulation voltage  */
79 	u8 iterm;	/* termination current */
80 	u8 iilimit;	/* input current limit */
81 	u8 vovp;	/* over voltage protection voltage */
82 	u8 vindpm;	/* VDMP input threshold voltage */
83 };
84 
85 struct bq24257_state {
86 	u8 status;
87 	u8 fault;
88 	bool power_good;
89 };
90 
91 struct bq24257_device {
92 	struct i2c_client *client;
93 	struct device *dev;
94 	struct power_supply *charger;
95 
96 	enum bq2425x_chip chip;
97 
98 	struct regmap *rmap;
99 	struct regmap_field *rmap_fields[F_MAX_FIELDS];
100 
101 	struct gpio_desc *pg;
102 
103 	struct delayed_work iilimit_setup_work;
104 
105 	struct bq24257_init_data init_data;
106 	struct bq24257_state state;
107 
108 	struct mutex lock; /* protect state data */
109 
110 	bool iilimit_autoset_enable;
111 };
112 
113 static bool bq24257_is_volatile_reg(struct device *dev, unsigned int reg)
114 {
115 	switch (reg) {
116 	case BQ24257_REG_2:
117 	case BQ24257_REG_4:
118 		return false;
119 
120 	default:
121 		return true;
122 	}
123 }
124 
125 static const struct regmap_config bq24257_regmap_config = {
126 	.reg_bits = 8,
127 	.val_bits = 8,
128 
129 	.max_register = BQ24257_REG_7,
130 	.cache_type = REGCACHE_RBTREE,
131 
132 	.volatile_reg = bq24257_is_volatile_reg,
133 };
134 
135 static const struct reg_field bq24257_reg_fields[] = {
136 	/* REG 1 */
137 	[F_WD_FAULT]		= REG_FIELD(BQ24257_REG_1, 7, 7),
138 	[F_WD_EN]		= REG_FIELD(BQ24257_REG_1, 6, 6),
139 	[F_STAT]		= REG_FIELD(BQ24257_REG_1, 4, 5),
140 	[F_FAULT]		= REG_FIELD(BQ24257_REG_1, 0, 3),
141 	/* REG 2 */
142 	[F_RESET]		= REG_FIELD(BQ24257_REG_2, 7, 7),
143 	[F_IILIMIT]		= REG_FIELD(BQ24257_REG_2, 4, 6),
144 	[F_EN_STAT]		= REG_FIELD(BQ24257_REG_2, 3, 3),
145 	[F_EN_TERM]		= REG_FIELD(BQ24257_REG_2, 2, 2),
146 	[F_CE]			= REG_FIELD(BQ24257_REG_2, 1, 1),
147 	[F_HZ_MODE]		= REG_FIELD(BQ24257_REG_2, 0, 0),
148 	/* REG 3 */
149 	[F_VBAT]		= REG_FIELD(BQ24257_REG_3, 2, 7),
150 	[F_USB_DET]		= REG_FIELD(BQ24257_REG_3, 0, 1),
151 	/* REG 4 */
152 	[F_ICHG]		= REG_FIELD(BQ24257_REG_4, 3, 7),
153 	[F_ITERM]		= REG_FIELD(BQ24257_REG_4, 0, 2),
154 	/* REG 5 */
155 	[F_LOOP_STATUS]		= REG_FIELD(BQ24257_REG_5, 6, 7),
156 	[F_LOW_CHG]		= REG_FIELD(BQ24257_REG_5, 5, 5),
157 	[F_DPDM_EN]		= REG_FIELD(BQ24257_REG_5, 4, 4),
158 	[F_CE_STATUS]		= REG_FIELD(BQ24257_REG_5, 3, 3),
159 	[F_VINDPM]		= REG_FIELD(BQ24257_REG_5, 0, 2),
160 	/* REG 6 */
161 	[F_X2_TMR_EN]		= REG_FIELD(BQ24257_REG_6, 7, 7),
162 	[F_TMR]			= REG_FIELD(BQ24257_REG_6, 5, 6),
163 	[F_SYSOFF]		= REG_FIELD(BQ24257_REG_6, 4, 4),
164 	[F_TS_EN]		= REG_FIELD(BQ24257_REG_6, 3, 3),
165 	[F_TS_STAT]		= REG_FIELD(BQ24257_REG_6, 0, 2),
166 	/* REG 7 */
167 	[F_VOVP]		= REG_FIELD(BQ24257_REG_7, 5, 7),
168 	[F_CLR_VDP]		= REG_FIELD(BQ24257_REG_7, 4, 4),
169 	[F_FORCE_BATDET]	= REG_FIELD(BQ24257_REG_7, 3, 3),
170 	[F_FORCE_PTM]		= REG_FIELD(BQ24257_REG_7, 2, 2)
171 };
172 
173 static const u32 bq24257_vbat_map[] = {
174 	3500000, 3520000, 3540000, 3560000, 3580000, 3600000, 3620000, 3640000,
175 	3660000, 3680000, 3700000, 3720000, 3740000, 3760000, 3780000, 3800000,
176 	3820000, 3840000, 3860000, 3880000, 3900000, 3920000, 3940000, 3960000,
177 	3980000, 4000000, 4020000, 4040000, 4060000, 4080000, 4100000, 4120000,
178 	4140000, 4160000, 4180000, 4200000, 4220000, 4240000, 4260000, 4280000,
179 	4300000, 4320000, 4340000, 4360000, 4380000, 4400000, 4420000, 4440000
180 };
181 
182 #define BQ24257_VBAT_MAP_SIZE		ARRAY_SIZE(bq24257_vbat_map)
183 
184 static const u32 bq24257_ichg_map[] = {
185 	500000, 550000, 600000, 650000, 700000, 750000, 800000, 850000, 900000,
186 	950000, 1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000,
187 	1350000, 1400000, 1450000, 1500000, 1550000, 1600000, 1650000, 1700000,
188 	1750000, 1800000, 1850000, 1900000, 1950000, 2000000
189 };
190 
191 #define BQ24257_ICHG_MAP_SIZE		ARRAY_SIZE(bq24257_ichg_map)
192 
193 static const u32 bq24257_iterm_map[] = {
194 	50000, 75000, 100000, 125000, 150000, 175000, 200000, 225000
195 };
196 
197 #define BQ24257_ITERM_MAP_SIZE		ARRAY_SIZE(bq24257_iterm_map)
198 
199 static const u32 bq24257_iilimit_map[] = {
200 	100000, 150000, 500000, 900000, 1500000, 2000000
201 };
202 
203 #define BQ24257_IILIMIT_MAP_SIZE	ARRAY_SIZE(bq24257_iilimit_map)
204 
205 static const u32 bq24257_vovp_map[] = {
206 	6000000, 6500000, 7000000, 8000000, 9000000, 9500000, 10000000,
207 	10500000
208 };
209 
210 #define BQ24257_VOVP_MAP_SIZE		ARRAY_SIZE(bq24257_vovp_map)
211 
212 static const u32 bq24257_vindpm_map[] = {
213 	4200000, 4280000, 4360000, 4440000, 4520000, 4600000, 4680000,
214 	4760000
215 };
216 
217 #define BQ24257_VINDPM_MAP_SIZE		ARRAY_SIZE(bq24257_vindpm_map)
218 
219 static int bq24257_field_read(struct bq24257_device *bq,
220 			      enum bq24257_fields field_id)
221 {
222 	int ret;
223 	int val;
224 
225 	ret = regmap_field_read(bq->rmap_fields[field_id], &val);
226 	if (ret < 0)
227 		return ret;
228 
229 	return val;
230 }
231 
232 static int bq24257_field_write(struct bq24257_device *bq,
233 			       enum bq24257_fields field_id, u8 val)
234 {
235 	return regmap_field_write(bq->rmap_fields[field_id], val);
236 }
237 
238 static u8 bq24257_find_idx(u32 value, const u32 *map, u8 map_size)
239 {
240 	u8 idx;
241 
242 	for (idx = 1; idx < map_size; idx++)
243 		if (value < map[idx])
244 			break;
245 
246 	return idx - 1;
247 }
248 
249 enum bq24257_status {
250 	STATUS_READY,
251 	STATUS_CHARGE_IN_PROGRESS,
252 	STATUS_CHARGE_DONE,
253 	STATUS_FAULT,
254 };
255 
256 enum bq24257_fault {
257 	FAULT_NORMAL,
258 	FAULT_INPUT_OVP,
259 	FAULT_INPUT_UVLO,
260 	FAULT_SLEEP,
261 	FAULT_BAT_TS,
262 	FAULT_BAT_OVP,
263 	FAULT_TS,
264 	FAULT_TIMER,
265 	FAULT_NO_BAT,
266 	FAULT_ISET,
267 	FAULT_INPUT_LDO_LOW,
268 };
269 
270 static int bq24257_get_input_current_limit(struct bq24257_device *bq,
271 					   union power_supply_propval *val)
272 {
273 	int ret;
274 
275 	ret = bq24257_field_read(bq, F_IILIMIT);
276 	if (ret < 0)
277 		return ret;
278 
279 	/*
280 	 * The "External ILIM" and "Production & Test" modes are not exposed
281 	 * through this driver and not being covered by the lookup table.
282 	 * Should such a mode have become active let's return an error rather
283 	 * than exceeding the bounds of the lookup table and returning
284 	 * garbage.
285 	 */
286 	if (ret >= BQ24257_IILIMIT_MAP_SIZE)
287 		return -ENODATA;
288 
289 	val->intval = bq24257_iilimit_map[ret];
290 
291 	return 0;
292 }
293 
294 static int bq24257_set_input_current_limit(struct bq24257_device *bq,
295 					const union power_supply_propval *val)
296 {
297 	/*
298 	 * Address the case where the user manually sets an input current limit
299 	 * while the charger auto-detection mechanism is is active. In this
300 	 * case we want to abort and go straight to the user-specified value.
301 	 */
302 	if (bq->iilimit_autoset_enable)
303 		cancel_delayed_work_sync(&bq->iilimit_setup_work);
304 
305 	return bq24257_field_write(bq, F_IILIMIT,
306 				   bq24257_find_idx(val->intval,
307 						    bq24257_iilimit_map,
308 						    BQ24257_IILIMIT_MAP_SIZE));
309 }
310 
311 static int bq24257_power_supply_get_property(struct power_supply *psy,
312 					     enum power_supply_property psp,
313 					     union power_supply_propval *val)
314 {
315 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
316 	struct bq24257_state state;
317 
318 	mutex_lock(&bq->lock);
319 	state = bq->state;
320 	mutex_unlock(&bq->lock);
321 
322 	switch (psp) {
323 	case POWER_SUPPLY_PROP_STATUS:
324 		if (!state.power_good)
325 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
326 		else if (state.status == STATUS_READY)
327 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
328 		else if (state.status == STATUS_CHARGE_IN_PROGRESS)
329 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
330 		else if (state.status == STATUS_CHARGE_DONE)
331 			val->intval = POWER_SUPPLY_STATUS_FULL;
332 		else
333 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
334 		break;
335 
336 	case POWER_SUPPLY_PROP_MANUFACTURER:
337 		val->strval = BQ24257_MANUFACTURER;
338 		break;
339 
340 	case POWER_SUPPLY_PROP_MODEL_NAME:
341 		val->strval = bq2425x_chip_name[bq->chip];
342 		break;
343 
344 	case POWER_SUPPLY_PROP_ONLINE:
345 		val->intval = state.power_good;
346 		break;
347 
348 	case POWER_SUPPLY_PROP_HEALTH:
349 		switch (state.fault) {
350 		case FAULT_NORMAL:
351 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
352 			break;
353 
354 		case FAULT_INPUT_OVP:
355 		case FAULT_BAT_OVP:
356 			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
357 			break;
358 
359 		case FAULT_TS:
360 		case FAULT_BAT_TS:
361 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
362 			break;
363 
364 		case FAULT_TIMER:
365 			val->intval = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
366 			break;
367 
368 		default:
369 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
370 			break;
371 		}
372 
373 		break;
374 
375 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
376 		val->intval = bq24257_ichg_map[bq->init_data.ichg];
377 		break;
378 
379 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
380 		val->intval = bq24257_ichg_map[BQ24257_ICHG_MAP_SIZE - 1];
381 		break;
382 
383 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
384 		val->intval = bq24257_vbat_map[bq->init_data.vbat];
385 		break;
386 
387 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
388 		val->intval = bq24257_vbat_map[BQ24257_VBAT_MAP_SIZE - 1];
389 		break;
390 
391 	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
392 		val->intval = bq24257_iterm_map[bq->init_data.iterm];
393 		break;
394 
395 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
396 		return bq24257_get_input_current_limit(bq, val);
397 
398 	default:
399 		return -EINVAL;
400 	}
401 
402 	return 0;
403 }
404 
405 static int bq24257_power_supply_set_property(struct power_supply *psy,
406 					enum power_supply_property prop,
407 					const union power_supply_propval *val)
408 {
409 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
410 
411 	switch (prop) {
412 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
413 		return bq24257_set_input_current_limit(bq, val);
414 	default:
415 		return -EINVAL;
416 	}
417 }
418 
419 static int bq24257_power_supply_property_is_writeable(struct power_supply *psy,
420 					enum power_supply_property psp)
421 {
422 	switch (psp) {
423 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
424 		return true;
425 	default:
426 		return false;
427 	}
428 }
429 
430 static int bq24257_get_chip_state(struct bq24257_device *bq,
431 				  struct bq24257_state *state)
432 {
433 	int ret;
434 
435 	ret = bq24257_field_read(bq, F_STAT);
436 	if (ret < 0)
437 		return ret;
438 
439 	state->status = ret;
440 
441 	ret = bq24257_field_read(bq, F_FAULT);
442 	if (ret < 0)
443 		return ret;
444 
445 	state->fault = ret;
446 
447 	if (bq->pg)
448 		state->power_good = !gpiod_get_value_cansleep(bq->pg);
449 	else
450 		/*
451 		 * If we have a chip without a dedicated power-good GPIO or
452 		 * some other explicit bit that would provide this information
453 		 * assume the power is good if there is no supply related
454 		 * fault - and not good otherwise. There is a possibility for
455 		 * other errors to mask that power in fact is not good but this
456 		 * is probably the best we can do here.
457 		 */
458 		switch (state->fault) {
459 		case FAULT_INPUT_OVP:
460 		case FAULT_INPUT_UVLO:
461 		case FAULT_INPUT_LDO_LOW:
462 			state->power_good = false;
463 			break;
464 		default:
465 			state->power_good = true;
466 		}
467 
468 	return 0;
469 }
470 
471 static bool bq24257_state_changed(struct bq24257_device *bq,
472 				  struct bq24257_state *new_state)
473 {
474 	int ret;
475 
476 	mutex_lock(&bq->lock);
477 	ret = (bq->state.status != new_state->status ||
478 	       bq->state.fault != new_state->fault ||
479 	       bq->state.power_good != new_state->power_good);
480 	mutex_unlock(&bq->lock);
481 
482 	return ret;
483 }
484 
485 enum bq24257_loop_status {
486 	LOOP_STATUS_NONE,
487 	LOOP_STATUS_IN_DPM,
488 	LOOP_STATUS_IN_CURRENT_LIMIT,
489 	LOOP_STATUS_THERMAL,
490 };
491 
492 enum bq24257_in_ilimit {
493 	IILIMIT_100,
494 	IILIMIT_150,
495 	IILIMIT_500,
496 	IILIMIT_900,
497 	IILIMIT_1500,
498 	IILIMIT_2000,
499 	IILIMIT_EXT,
500 	IILIMIT_NONE,
501 };
502 
503 enum bq24257_vovp {
504 	VOVP_6000,
505 	VOVP_6500,
506 	VOVP_7000,
507 	VOVP_8000,
508 	VOVP_9000,
509 	VOVP_9500,
510 	VOVP_10000,
511 	VOVP_10500
512 };
513 
514 enum bq24257_vindpm {
515 	VINDPM_4200,
516 	VINDPM_4280,
517 	VINDPM_4360,
518 	VINDPM_4440,
519 	VINDPM_4520,
520 	VINDPM_4600,
521 	VINDPM_4680,
522 	VINDPM_4760
523 };
524 
525 enum bq24257_port_type {
526 	PORT_TYPE_DCP,		/* Dedicated Charging Port */
527 	PORT_TYPE_CDP,		/* Charging Downstream Port */
528 	PORT_TYPE_SDP,		/* Standard Downstream Port */
529 	PORT_TYPE_NON_STANDARD,
530 };
531 
532 enum bq24257_safety_timer {
533 	SAFETY_TIMER_45,
534 	SAFETY_TIMER_360,
535 	SAFETY_TIMER_540,
536 	SAFETY_TIMER_NONE,
537 };
538 
539 static int bq24257_iilimit_autoset(struct bq24257_device *bq)
540 {
541 	int loop_status;
542 	int iilimit;
543 	int port_type;
544 	int ret;
545 	const u8 new_iilimit[] = {
546 		[PORT_TYPE_DCP] = IILIMIT_2000,
547 		[PORT_TYPE_CDP] = IILIMIT_2000,
548 		[PORT_TYPE_SDP] = IILIMIT_500,
549 		[PORT_TYPE_NON_STANDARD] = IILIMIT_500
550 	};
551 
552 	ret = bq24257_field_read(bq, F_LOOP_STATUS);
553 	if (ret < 0)
554 		goto error;
555 
556 	loop_status = ret;
557 
558 	ret = bq24257_field_read(bq, F_IILIMIT);
559 	if (ret < 0)
560 		goto error;
561 
562 	iilimit = ret;
563 
564 	/*
565 	 * All USB ports should be able to handle 500mA. If not, DPM will lower
566 	 * the charging current to accommodate the power source. No need to set
567 	 * a lower IILIMIT value.
568 	 */
569 	if (loop_status == LOOP_STATUS_IN_DPM && iilimit == IILIMIT_500)
570 		return 0;
571 
572 	ret = bq24257_field_read(bq, F_USB_DET);
573 	if (ret < 0)
574 		goto error;
575 
576 	port_type = ret;
577 
578 	ret = bq24257_field_write(bq, F_IILIMIT, new_iilimit[port_type]);
579 	if (ret < 0)
580 		goto error;
581 
582 	ret = bq24257_field_write(bq, F_TMR, SAFETY_TIMER_360);
583 	if (ret < 0)
584 		goto error;
585 
586 	ret = bq24257_field_write(bq, F_CLR_VDP, 1);
587 	if (ret < 0)
588 		goto error;
589 
590 	dev_dbg(bq->dev, "port/loop = %d/%d -> iilimit = %d\n",
591 		port_type, loop_status, new_iilimit[port_type]);
592 
593 	return 0;
594 
595 error:
596 	dev_err(bq->dev, "%s: Error communicating with the chip.\n", __func__);
597 	return ret;
598 }
599 
600 static void bq24257_iilimit_setup_work(struct work_struct *work)
601 {
602 	struct bq24257_device *bq = container_of(work, struct bq24257_device,
603 						 iilimit_setup_work.work);
604 
605 	bq24257_iilimit_autoset(bq);
606 }
607 
608 static void bq24257_handle_state_change(struct bq24257_device *bq,
609 					struct bq24257_state *new_state)
610 {
611 	int ret;
612 	struct bq24257_state old_state;
613 
614 	mutex_lock(&bq->lock);
615 	old_state = bq->state;
616 	mutex_unlock(&bq->lock);
617 
618 	/*
619 	 * Handle BQ2425x state changes observing whether the D+/D- based input
620 	 * current limit autoset functionality is enabled.
621 	 */
622 	if (!new_state->power_good) {
623 		dev_dbg(bq->dev, "Power removed\n");
624 		if (bq->iilimit_autoset_enable) {
625 			cancel_delayed_work_sync(&bq->iilimit_setup_work);
626 
627 			/* activate D+/D- port detection algorithm */
628 			ret = bq24257_field_write(bq, F_DPDM_EN, 1);
629 			if (ret < 0)
630 				goto error;
631 		}
632 		/*
633 		 * When power is removed always return to the default input
634 		 * current limit as configured during probe.
635 		 */
636 		ret = bq24257_field_write(bq, F_IILIMIT, bq->init_data.iilimit);
637 		if (ret < 0)
638 			goto error;
639 	} else if (!old_state.power_good) {
640 		dev_dbg(bq->dev, "Power inserted\n");
641 
642 		if (bq->iilimit_autoset_enable)
643 			/* configure input current limit */
644 			schedule_delayed_work(&bq->iilimit_setup_work,
645 				      msecs_to_jiffies(BQ24257_ILIM_SET_DELAY));
646 	} else if (new_state->fault == FAULT_NO_BAT) {
647 		dev_warn(bq->dev, "Battery removed\n");
648 	} else if (new_state->fault == FAULT_TIMER) {
649 		dev_err(bq->dev, "Safety timer expired! Battery dead?\n");
650 	}
651 
652 	return;
653 
654 error:
655 	dev_err(bq->dev, "%s: Error communicating with the chip.\n", __func__);
656 }
657 
658 static irqreturn_t bq24257_irq_handler_thread(int irq, void *private)
659 {
660 	int ret;
661 	struct bq24257_device *bq = private;
662 	struct bq24257_state state;
663 
664 	ret = bq24257_get_chip_state(bq, &state);
665 	if (ret < 0)
666 		return IRQ_HANDLED;
667 
668 	if (!bq24257_state_changed(bq, &state))
669 		return IRQ_HANDLED;
670 
671 	dev_dbg(bq->dev, "irq(state changed): status/fault/pg = %d/%d/%d\n",
672 		state.status, state.fault, state.power_good);
673 
674 	bq24257_handle_state_change(bq, &state);
675 
676 	mutex_lock(&bq->lock);
677 	bq->state = state;
678 	mutex_unlock(&bq->lock);
679 
680 	power_supply_changed(bq->charger);
681 
682 	return IRQ_HANDLED;
683 }
684 
685 static int bq24257_hw_init(struct bq24257_device *bq)
686 {
687 	int ret;
688 	int i;
689 	struct bq24257_state state;
690 
691 	const struct {
692 		int field;
693 		u32 value;
694 	} init_data[] = {
695 		{F_ICHG, bq->init_data.ichg},
696 		{F_VBAT, bq->init_data.vbat},
697 		{F_ITERM, bq->init_data.iterm},
698 		{F_VOVP, bq->init_data.vovp},
699 		{F_VINDPM, bq->init_data.vindpm},
700 	};
701 
702 	/*
703 	 * Disable the watchdog timer to prevent the IC from going back to
704 	 * default settings after 50 seconds of I2C inactivity.
705 	 */
706 	ret = bq24257_field_write(bq, F_WD_EN, 0);
707 	if (ret < 0)
708 		return ret;
709 
710 	/* configure the charge currents and voltages */
711 	for (i = 0; i < ARRAY_SIZE(init_data); i++) {
712 		ret = bq24257_field_write(bq, init_data[i].field,
713 					  init_data[i].value);
714 		if (ret < 0)
715 			return ret;
716 	}
717 
718 	ret = bq24257_get_chip_state(bq, &state);
719 	if (ret < 0)
720 		return ret;
721 
722 	mutex_lock(&bq->lock);
723 	bq->state = state;
724 	mutex_unlock(&bq->lock);
725 
726 	if (!bq->iilimit_autoset_enable) {
727 		dev_dbg(bq->dev, "manually setting iilimit = %u\n",
728 			bq->init_data.iilimit);
729 
730 		/* program fixed input current limit */
731 		ret = bq24257_field_write(bq, F_IILIMIT,
732 					  bq->init_data.iilimit);
733 		if (ret < 0)
734 			return ret;
735 	} else if (!state.power_good)
736 		/* activate D+/D- detection algorithm */
737 		ret = bq24257_field_write(bq, F_DPDM_EN, 1);
738 	else if (state.fault != FAULT_NO_BAT)
739 		ret = bq24257_iilimit_autoset(bq);
740 
741 	return ret;
742 }
743 
744 static enum power_supply_property bq24257_power_supply_props[] = {
745 	POWER_SUPPLY_PROP_MANUFACTURER,
746 	POWER_SUPPLY_PROP_MODEL_NAME,
747 	POWER_SUPPLY_PROP_STATUS,
748 	POWER_SUPPLY_PROP_ONLINE,
749 	POWER_SUPPLY_PROP_HEALTH,
750 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
751 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
752 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
753 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
754 	POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,
755 	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
756 };
757 
758 static char *bq24257_charger_supplied_to[] = {
759 	"main-battery",
760 };
761 
762 static const struct power_supply_desc bq24257_power_supply_desc = {
763 	.name = "bq24257-charger",
764 	.type = POWER_SUPPLY_TYPE_USB,
765 	.properties = bq24257_power_supply_props,
766 	.num_properties = ARRAY_SIZE(bq24257_power_supply_props),
767 	.get_property = bq24257_power_supply_get_property,
768 	.set_property = bq24257_power_supply_set_property,
769 	.property_is_writeable = bq24257_power_supply_property_is_writeable,
770 };
771 
772 static ssize_t bq24257_show_ovp_voltage(struct device *dev,
773 					struct device_attribute *attr,
774 					char *buf)
775 {
776 	struct power_supply *psy = dev_get_drvdata(dev);
777 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
778 
779 	return scnprintf(buf, PAGE_SIZE, "%u\n",
780 			 bq24257_vovp_map[bq->init_data.vovp]);
781 }
782 
783 static ssize_t bq24257_show_in_dpm_voltage(struct device *dev,
784 					   struct device_attribute *attr,
785 					   char *buf)
786 {
787 	struct power_supply *psy = dev_get_drvdata(dev);
788 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
789 
790 	return scnprintf(buf, PAGE_SIZE, "%u\n",
791 			 bq24257_vindpm_map[bq->init_data.vindpm]);
792 }
793 
794 static ssize_t bq24257_sysfs_show_enable(struct device *dev,
795 					 struct device_attribute *attr,
796 					 char *buf)
797 {
798 	struct power_supply *psy = dev_get_drvdata(dev);
799 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
800 	int ret;
801 
802 	if (strcmp(attr->attr.name, "high_impedance_enable") == 0)
803 		ret = bq24257_field_read(bq, F_HZ_MODE);
804 	else if (strcmp(attr->attr.name, "sysoff_enable") == 0)
805 		ret = bq24257_field_read(bq, F_SYSOFF);
806 	else
807 		return -EINVAL;
808 
809 	if (ret < 0)
810 		return ret;
811 
812 	return scnprintf(buf, PAGE_SIZE, "%d\n", ret);
813 }
814 
815 static ssize_t bq24257_sysfs_set_enable(struct device *dev,
816 					struct device_attribute *attr,
817 					const char *buf,
818 					size_t count)
819 {
820 	struct power_supply *psy = dev_get_drvdata(dev);
821 	struct bq24257_device *bq = power_supply_get_drvdata(psy);
822 	long val;
823 	int ret;
824 
825 	if (kstrtol(buf, 10, &val) < 0)
826 		return -EINVAL;
827 
828 	if (strcmp(attr->attr.name, "high_impedance_enable") == 0)
829 		ret = bq24257_field_write(bq, F_HZ_MODE, (bool)val);
830 	else if (strcmp(attr->attr.name, "sysoff_enable") == 0)
831 		ret = bq24257_field_write(bq, F_SYSOFF, (bool)val);
832 	else
833 		return -EINVAL;
834 
835 	if (ret < 0)
836 		return ret;
837 
838 	return count;
839 }
840 
841 static DEVICE_ATTR(ovp_voltage, S_IRUGO, bq24257_show_ovp_voltage, NULL);
842 static DEVICE_ATTR(in_dpm_voltage, S_IRUGO, bq24257_show_in_dpm_voltage, NULL);
843 static DEVICE_ATTR(high_impedance_enable, S_IWUSR | S_IRUGO,
844 		   bq24257_sysfs_show_enable, bq24257_sysfs_set_enable);
845 static DEVICE_ATTR(sysoff_enable, S_IWUSR | S_IRUGO,
846 		   bq24257_sysfs_show_enable, bq24257_sysfs_set_enable);
847 
848 static struct attribute *bq24257_charger_attr[] = {
849 	&dev_attr_ovp_voltage.attr,
850 	&dev_attr_in_dpm_voltage.attr,
851 	&dev_attr_high_impedance_enable.attr,
852 	&dev_attr_sysoff_enable.attr,
853 	NULL,
854 };
855 
856 static const struct attribute_group bq24257_attr_group = {
857 	.attrs = bq24257_charger_attr,
858 };
859 
860 static int bq24257_power_supply_init(struct bq24257_device *bq)
861 {
862 	struct power_supply_config psy_cfg = { .drv_data = bq, };
863 
864 	psy_cfg.supplied_to = bq24257_charger_supplied_to;
865 	psy_cfg.num_supplicants = ARRAY_SIZE(bq24257_charger_supplied_to);
866 
867 	bq->charger = devm_power_supply_register(bq->dev,
868 						 &bq24257_power_supply_desc,
869 						 &psy_cfg);
870 
871 	return PTR_ERR_OR_ZERO(bq->charger);
872 }
873 
874 static void bq24257_pg_gpio_probe(struct bq24257_device *bq)
875 {
876 	bq->pg = devm_gpiod_get_optional(bq->dev, BQ24257_PG_GPIO, GPIOD_IN);
877 
878 	if (PTR_ERR(bq->pg) == -EPROBE_DEFER) {
879 		dev_info(bq->dev, "probe retry requested for PG pin\n");
880 		return;
881 	} else if (IS_ERR(bq->pg)) {
882 		dev_err(bq->dev, "error probing PG pin\n");
883 		bq->pg = NULL;
884 		return;
885 	}
886 
887 	if (bq->pg)
888 		dev_dbg(bq->dev, "probed PG pin = %d\n", desc_to_gpio(bq->pg));
889 }
890 
891 static int bq24257_fw_probe(struct bq24257_device *bq)
892 {
893 	int ret;
894 	u32 property;
895 
896 	/* Required properties */
897 	ret = device_property_read_u32(bq->dev, "ti,charge-current", &property);
898 	if (ret < 0)
899 		return ret;
900 
901 	bq->init_data.ichg = bq24257_find_idx(property, bq24257_ichg_map,
902 					      BQ24257_ICHG_MAP_SIZE);
903 
904 	ret = device_property_read_u32(bq->dev, "ti,battery-regulation-voltage",
905 				       &property);
906 	if (ret < 0)
907 		return ret;
908 
909 	bq->init_data.vbat = bq24257_find_idx(property, bq24257_vbat_map,
910 					      BQ24257_VBAT_MAP_SIZE);
911 
912 	ret = device_property_read_u32(bq->dev, "ti,termination-current",
913 				       &property);
914 	if (ret < 0)
915 		return ret;
916 
917 	bq->init_data.iterm = bq24257_find_idx(property, bq24257_iterm_map,
918 					       BQ24257_ITERM_MAP_SIZE);
919 
920 	/* Optional properties. If not provided use reasonable default. */
921 	ret = device_property_read_u32(bq->dev, "ti,current-limit",
922 				       &property);
923 	if (ret < 0) {
924 		bq->iilimit_autoset_enable = true;
925 
926 		/*
927 		 * Explicitly set a default value which will be needed for
928 		 * devices that don't support the automatic setting of the input
929 		 * current limit through the charger type detection mechanism.
930 		 */
931 		bq->init_data.iilimit = IILIMIT_500;
932 	} else
933 		bq->init_data.iilimit =
934 				bq24257_find_idx(property,
935 						 bq24257_iilimit_map,
936 						 BQ24257_IILIMIT_MAP_SIZE);
937 
938 	ret = device_property_read_u32(bq->dev, "ti,ovp-voltage",
939 				       &property);
940 	if (ret < 0)
941 		bq->init_data.vovp = VOVP_6500;
942 	else
943 		bq->init_data.vovp = bq24257_find_idx(property,
944 						      bq24257_vovp_map,
945 						      BQ24257_VOVP_MAP_SIZE);
946 
947 	ret = device_property_read_u32(bq->dev, "ti,in-dpm-voltage",
948 				       &property);
949 	if (ret < 0)
950 		bq->init_data.vindpm = VINDPM_4360;
951 	else
952 		bq->init_data.vindpm =
953 				bq24257_find_idx(property,
954 						 bq24257_vindpm_map,
955 						 BQ24257_VINDPM_MAP_SIZE);
956 
957 	return 0;
958 }
959 
960 static int bq24257_probe(struct i2c_client *client,
961 			 const struct i2c_device_id *id)
962 {
963 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
964 	struct device *dev = &client->dev;
965 	const struct acpi_device_id *acpi_id;
966 	struct bq24257_device *bq;
967 	int ret;
968 	int i;
969 
970 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
971 		dev_err(dev, "No support for SMBUS_BYTE_DATA\n");
972 		return -ENODEV;
973 	}
974 
975 	bq = devm_kzalloc(dev, sizeof(*bq), GFP_KERNEL);
976 	if (!bq)
977 		return -ENOMEM;
978 
979 	bq->client = client;
980 	bq->dev = dev;
981 
982 	if (ACPI_HANDLE(dev)) {
983 		acpi_id = acpi_match_device(dev->driver->acpi_match_table,
984 					    &client->dev);
985 		if (!acpi_id) {
986 			dev_err(dev, "Failed to match ACPI device\n");
987 			return -ENODEV;
988 		}
989 		bq->chip = (enum bq2425x_chip)acpi_id->driver_data;
990 	} else {
991 		bq->chip = (enum bq2425x_chip)id->driver_data;
992 	}
993 
994 	mutex_init(&bq->lock);
995 
996 	bq->rmap = devm_regmap_init_i2c(client, &bq24257_regmap_config);
997 	if (IS_ERR(bq->rmap)) {
998 		dev_err(dev, "failed to allocate register map\n");
999 		return PTR_ERR(bq->rmap);
1000 	}
1001 
1002 	for (i = 0; i < ARRAY_SIZE(bq24257_reg_fields); i++) {
1003 		const struct reg_field *reg_fields = bq24257_reg_fields;
1004 
1005 		bq->rmap_fields[i] = devm_regmap_field_alloc(dev, bq->rmap,
1006 							     reg_fields[i]);
1007 		if (IS_ERR(bq->rmap_fields[i])) {
1008 			dev_err(dev, "cannot allocate regmap field\n");
1009 			return PTR_ERR(bq->rmap_fields[i]);
1010 		}
1011 	}
1012 
1013 	i2c_set_clientdata(client, bq);
1014 
1015 	if (!dev->platform_data) {
1016 		ret = bq24257_fw_probe(bq);
1017 		if (ret < 0) {
1018 			dev_err(dev, "Cannot read device properties.\n");
1019 			return ret;
1020 		}
1021 	} else {
1022 		return -ENODEV;
1023 	}
1024 
1025 	/*
1026 	 * The BQ24250 doesn't support the D+/D- based charger type detection
1027 	 * used for the automatic setting of the input current limit setting so
1028 	 * explicitly disable that feature.
1029 	 */
1030 	if (bq->chip == BQ24250)
1031 		bq->iilimit_autoset_enable = false;
1032 
1033 	if (bq->iilimit_autoset_enable)
1034 		INIT_DELAYED_WORK(&bq->iilimit_setup_work,
1035 				  bq24257_iilimit_setup_work);
1036 
1037 	/*
1038 	 * The BQ24250 doesn't have a dedicated Power Good (PG) pin so let's
1039 	 * not probe for it and instead use a SW-based approach to determine
1040 	 * the PG state. We also use a SW-based approach for all other devices
1041 	 * if the PG pin is either not defined or can't be probed.
1042 	 */
1043 	if (bq->chip != BQ24250)
1044 		bq24257_pg_gpio_probe(bq);
1045 
1046 	if (PTR_ERR(bq->pg) == -EPROBE_DEFER)
1047 		return PTR_ERR(bq->pg);
1048 	else if (!bq->pg)
1049 		dev_info(bq->dev, "using SW-based power-good detection\n");
1050 
1051 	/* reset all registers to defaults */
1052 	ret = bq24257_field_write(bq, F_RESET, 1);
1053 	if (ret < 0)
1054 		return ret;
1055 
1056 	/*
1057 	 * Put the RESET bit back to 0, in cache. For some reason the HW always
1058 	 * returns 1 on this bit, so this is the only way to avoid resetting the
1059 	 * chip every time we update another field in this register.
1060 	 */
1061 	ret = bq24257_field_write(bq, F_RESET, 0);
1062 	if (ret < 0)
1063 		return ret;
1064 
1065 	ret = bq24257_hw_init(bq);
1066 	if (ret < 0) {
1067 		dev_err(dev, "Cannot initialize the chip.\n");
1068 		return ret;
1069 	}
1070 
1071 	ret = bq24257_power_supply_init(bq);
1072 	if (ret < 0) {
1073 		dev_err(dev, "Failed to register power supply\n");
1074 		return ret;
1075 	}
1076 
1077 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
1078 					bq24257_irq_handler_thread,
1079 					IRQF_TRIGGER_FALLING |
1080 					IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1081 					bq2425x_chip_name[bq->chip], bq);
1082 	if (ret) {
1083 		dev_err(dev, "Failed to request IRQ #%d\n", client->irq);
1084 		return ret;
1085 	}
1086 
1087 	ret = sysfs_create_group(&bq->charger->dev.kobj, &bq24257_attr_group);
1088 	if (ret < 0) {
1089 		dev_err(dev, "Can't create sysfs entries\n");
1090 		return ret;
1091 	}
1092 
1093 	return 0;
1094 }
1095 
1096 static int bq24257_remove(struct i2c_client *client)
1097 {
1098 	struct bq24257_device *bq = i2c_get_clientdata(client);
1099 
1100 	if (bq->iilimit_autoset_enable)
1101 		cancel_delayed_work_sync(&bq->iilimit_setup_work);
1102 
1103 	sysfs_remove_group(&bq->charger->dev.kobj, &bq24257_attr_group);
1104 
1105 	bq24257_field_write(bq, F_RESET, 1); /* reset to defaults */
1106 
1107 	return 0;
1108 }
1109 
1110 #ifdef CONFIG_PM_SLEEP
1111 static int bq24257_suspend(struct device *dev)
1112 {
1113 	struct bq24257_device *bq = dev_get_drvdata(dev);
1114 	int ret = 0;
1115 
1116 	if (bq->iilimit_autoset_enable)
1117 		cancel_delayed_work_sync(&bq->iilimit_setup_work);
1118 
1119 	/* reset all registers to default (and activate standalone mode) */
1120 	ret = bq24257_field_write(bq, F_RESET, 1);
1121 	if (ret < 0)
1122 		dev_err(bq->dev, "Cannot reset chip to standalone mode.\n");
1123 
1124 	return ret;
1125 }
1126 
1127 static int bq24257_resume(struct device *dev)
1128 {
1129 	int ret;
1130 	struct bq24257_device *bq = dev_get_drvdata(dev);
1131 
1132 	ret = regcache_drop_region(bq->rmap, BQ24257_REG_1, BQ24257_REG_7);
1133 	if (ret < 0)
1134 		return ret;
1135 
1136 	ret = bq24257_field_write(bq, F_RESET, 0);
1137 	if (ret < 0)
1138 		return ret;
1139 
1140 	ret = bq24257_hw_init(bq);
1141 	if (ret < 0) {
1142 		dev_err(bq->dev, "Cannot init chip after resume.\n");
1143 		return ret;
1144 	}
1145 
1146 	/* signal userspace, maybe state changed while suspended */
1147 	power_supply_changed(bq->charger);
1148 
1149 	return 0;
1150 }
1151 #endif
1152 
1153 static const struct dev_pm_ops bq24257_pm = {
1154 	SET_SYSTEM_SLEEP_PM_OPS(bq24257_suspend, bq24257_resume)
1155 };
1156 
1157 static const struct i2c_device_id bq24257_i2c_ids[] = {
1158 	{ "bq24250", BQ24250 },
1159 	{ "bq24251", BQ24251 },
1160 	{ "bq24257", BQ24257 },
1161 	{},
1162 };
1163 MODULE_DEVICE_TABLE(i2c, bq24257_i2c_ids);
1164 
1165 static const struct of_device_id bq24257_of_match[] = {
1166 	{ .compatible = "ti,bq24250", },
1167 	{ .compatible = "ti,bq24251", },
1168 	{ .compatible = "ti,bq24257", },
1169 	{ },
1170 };
1171 MODULE_DEVICE_TABLE(of, bq24257_of_match);
1172 
1173 static const struct acpi_device_id bq24257_acpi_match[] = {
1174 	{ "BQ242500", BQ24250 },
1175 	{ "BQ242510", BQ24251 },
1176 	{ "BQ242570", BQ24257 },
1177 	{},
1178 };
1179 MODULE_DEVICE_TABLE(acpi, bq24257_acpi_match);
1180 
1181 static struct i2c_driver bq24257_driver = {
1182 	.driver = {
1183 		.name = "bq24257-charger",
1184 		.of_match_table = of_match_ptr(bq24257_of_match),
1185 		.acpi_match_table = ACPI_PTR(bq24257_acpi_match),
1186 		.pm = &bq24257_pm,
1187 	},
1188 	.probe = bq24257_probe,
1189 	.remove = bq24257_remove,
1190 	.id_table = bq24257_i2c_ids,
1191 };
1192 module_i2c_driver(bq24257_driver);
1193 
1194 MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>");
1195 MODULE_DESCRIPTION("bq24257 charger driver");
1196 MODULE_LICENSE("GPL");
1197