xref: /linux/drivers/power/supply/max77693_charger.c (revision 448ecd5771e255629bef0fb16c9b78c4bbd7bd56)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // max77693_charger.c - Battery charger driver for the Maxim 77693
4 //
5 // Copyright (C) 2014 Samsung Electronics
6 // Krzysztof Kozlowski <krzk@kernel.org>
7 
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/power_supply.h>
11 #include <linux/regmap.h>
12 #include <linux/mfd/max77693.h>
13 #include <linux/mfd/max77693-common.h>
14 #include <linux/mfd/max77693-private.h>
15 
16 #define MAX77693_CHARGER_NAME				"max77693-charger"
17 static const char *max77693_charger_model		= "MAX77693";
18 static const char *max77693_charger_manufacturer	= "Maxim Integrated";
19 
20 struct max77693_charger {
21 	struct device		*dev;
22 	struct max77693_dev	*max77693;
23 	struct power_supply	*charger;
24 
25 	u32 constant_volt;
26 	u32 min_system_volt;
27 	u32 thermal_regulation_temp;
28 	u32 batttery_overcurrent;
29 	u32 charge_input_threshold_volt;
30 };
31 
max77693_get_charger_state(struct regmap * regmap,int * val)32 static int max77693_get_charger_state(struct regmap *regmap, int *val)
33 {
34 	int ret;
35 	unsigned int data;
36 
37 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
38 	if (ret < 0)
39 		return ret;
40 
41 	data &= CHG_DETAILS_01_CHG_MASK;
42 	data >>= CHG_DETAILS_01_CHG_SHIFT;
43 
44 	switch (data) {
45 	case MAX77693_CHARGING_PREQUALIFICATION:
46 	case MAX77693_CHARGING_FAST_CONST_CURRENT:
47 	case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
48 	case MAX77693_CHARGING_TOP_OFF:
49 	/* In high temp the charging current is reduced, but still charging */
50 	case MAX77693_CHARGING_HIGH_TEMP:
51 		*val = POWER_SUPPLY_STATUS_CHARGING;
52 		break;
53 	case MAX77693_CHARGING_DONE:
54 		*val = POWER_SUPPLY_STATUS_FULL;
55 		break;
56 	case MAX77693_CHARGING_TIMER_EXPIRED:
57 	case MAX77693_CHARGING_THERMISTOR_SUSPEND:
58 		*val = POWER_SUPPLY_STATUS_NOT_CHARGING;
59 		break;
60 	case MAX77693_CHARGING_OFF:
61 	case MAX77693_CHARGING_OVER_TEMP:
62 	case MAX77693_CHARGING_WATCHDOG_EXPIRED:
63 		*val = POWER_SUPPLY_STATUS_DISCHARGING;
64 		break;
65 	case MAX77693_CHARGING_RESERVED:
66 	default:
67 		*val = POWER_SUPPLY_STATUS_UNKNOWN;
68 	}
69 
70 	return 0;
71 }
72 
max77693_get_charge_type(struct regmap * regmap,int * val)73 static int max77693_get_charge_type(struct regmap *regmap, int *val)
74 {
75 	int ret;
76 	unsigned int data;
77 
78 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
79 	if (ret < 0)
80 		return ret;
81 
82 	data &= CHG_DETAILS_01_CHG_MASK;
83 	data >>= CHG_DETAILS_01_CHG_SHIFT;
84 
85 	switch (data) {
86 	case MAX77693_CHARGING_PREQUALIFICATION:
87 	/*
88 	 * Top-off: trickle or fast? In top-off the current varies between
89 	 * 100 and 250 mA. It is higher than prequalification current.
90 	 */
91 	case MAX77693_CHARGING_TOP_OFF:
92 		*val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
93 		break;
94 	case MAX77693_CHARGING_FAST_CONST_CURRENT:
95 	case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
96 	/* In high temp the charging current is reduced, but still charging */
97 	case MAX77693_CHARGING_HIGH_TEMP:
98 		*val = POWER_SUPPLY_CHARGE_TYPE_FAST;
99 		break;
100 	case MAX77693_CHARGING_DONE:
101 	case MAX77693_CHARGING_TIMER_EXPIRED:
102 	case MAX77693_CHARGING_THERMISTOR_SUSPEND:
103 	case MAX77693_CHARGING_OFF:
104 	case MAX77693_CHARGING_OVER_TEMP:
105 	case MAX77693_CHARGING_WATCHDOG_EXPIRED:
106 		*val = POWER_SUPPLY_CHARGE_TYPE_NONE;
107 		break;
108 	case MAX77693_CHARGING_RESERVED:
109 	default:
110 		*val = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
111 	}
112 
113 	return 0;
114 }
115 
116 /*
117  * Supported health statuses:
118  *  - POWER_SUPPLY_HEALTH_DEAD
119  *  - POWER_SUPPLY_HEALTH_GOOD
120  *  - POWER_SUPPLY_HEALTH_OVERVOLTAGE
121  *  - POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE
122  *  - POWER_SUPPLY_HEALTH_UNKNOWN
123  *  - POWER_SUPPLY_HEALTH_UNSPEC_FAILURE
124  */
max77693_get_battery_health(struct regmap * regmap,int * val)125 static int max77693_get_battery_health(struct regmap *regmap, int *val)
126 {
127 	int ret;
128 	unsigned int data;
129 
130 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
131 	if (ret < 0)
132 		return ret;
133 
134 	data &= CHG_DETAILS_01_BAT_MASK;
135 	data >>= CHG_DETAILS_01_BAT_SHIFT;
136 
137 	switch (data) {
138 	case MAX77693_BATTERY_NOBAT:
139 		*val = POWER_SUPPLY_HEALTH_DEAD;
140 		break;
141 	case MAX77693_BATTERY_PREQUALIFICATION:
142 	case MAX77693_BATTERY_GOOD:
143 	case MAX77693_BATTERY_LOWVOLTAGE:
144 		*val = POWER_SUPPLY_HEALTH_GOOD;
145 		break;
146 	case MAX77693_BATTERY_TIMER_EXPIRED:
147 		/*
148 		 * Took longer to charge than expected, charging suspended.
149 		 * Damaged battery?
150 		 */
151 		*val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
152 		break;
153 	case MAX77693_BATTERY_OVERVOLTAGE:
154 		*val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
155 		break;
156 	case MAX77693_BATTERY_OVERCURRENT:
157 		*val = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
158 		break;
159 	case MAX77693_BATTERY_RESERVED:
160 	default:
161 		*val = POWER_SUPPLY_HEALTH_UNKNOWN;
162 		break;
163 	}
164 
165 	return 0;
166 }
167 
max77693_get_present(struct regmap * regmap,int * val)168 static int max77693_get_present(struct regmap *regmap, int *val)
169 {
170 	unsigned int data;
171 	int ret;
172 
173 	/*
174 	 * Read CHG_INT_OK register. High DETBAT bit here should be
175 	 * equal to value 0x0 in CHG_DETAILS_01/BAT field.
176 	 */
177 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
178 	if (ret < 0)
179 		return ret;
180 
181 	*val = (data & CHG_INT_OK_DETBAT_MASK) ? 0 : 1;
182 
183 	return 0;
184 }
185 
max77693_get_online(struct regmap * regmap,int * val)186 static int max77693_get_online(struct regmap *regmap, int *val)
187 {
188 	unsigned int data;
189 	int ret;
190 
191 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
192 	if (ret < 0)
193 		return ret;
194 
195 	*val = (data & CHG_INT_OK_CHGIN_MASK) ? 1 : 0;
196 
197 	return 0;
198 }
199 
200 /*
201  * There are *two* current limit registers:
202  * - CHGIN limit, which limits the input current from the external charger;
203  * - Fast charge current limit, which limits the current going to the battery.
204  */
205 
max77693_get_input_current_limit(struct regmap * regmap,int * val)206 static int max77693_get_input_current_limit(struct regmap *regmap, int *val)
207 {
208 	unsigned int data;
209 	int ret;
210 
211 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_CNFG_09, &data);
212 	if (ret < 0)
213 		return ret;
214 
215 	data &= CHG_CNFG_09_CHGIN_ILIM_MASK;
216 	data >>= CHG_CNFG_09_CHGIN_ILIM_SHIFT;
217 
218 	if (data <= 0x03)
219 		/* The first four values (0x00..0x03) are 60mA */
220 		*val = 60000;
221 	else
222 		*val = data * 20000; /* 20mA steps */
223 
224 	return 0;
225 }
226 
max77693_get_fast_charge_current(struct regmap * regmap,int * val)227 static int max77693_get_fast_charge_current(struct regmap *regmap, int *val)
228 {
229 	unsigned int data;
230 	int ret;
231 
232 	ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_CNFG_02, &data);
233 	if (ret < 0)
234 		return ret;
235 
236 	data &= CHG_CNFG_02_CC_MASK;
237 	data >>= CHG_CNFG_02_CC_SHIFT;
238 
239 	*val = data * 33300; /* 33.3mA steps */
240 
241 	return 0;
242 }
243 
244 static enum power_supply_property max77693_charger_props[] = {
245 	POWER_SUPPLY_PROP_STATUS,
246 	POWER_SUPPLY_PROP_CHARGE_TYPE,
247 	POWER_SUPPLY_PROP_HEALTH,
248 	POWER_SUPPLY_PROP_PRESENT,
249 	POWER_SUPPLY_PROP_ONLINE,
250 	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
251 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
252 	POWER_SUPPLY_PROP_MODEL_NAME,
253 	POWER_SUPPLY_PROP_MANUFACTURER,
254 };
255 
max77693_charger_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)256 static int max77693_charger_get_property(struct power_supply *psy,
257 			    enum power_supply_property psp,
258 			    union power_supply_propval *val)
259 {
260 	struct max77693_charger *chg = power_supply_get_drvdata(psy);
261 	struct regmap *regmap = chg->max77693->regmap;
262 	int ret = 0;
263 
264 	switch (psp) {
265 	case POWER_SUPPLY_PROP_STATUS:
266 		ret = max77693_get_charger_state(regmap, &val->intval);
267 		break;
268 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
269 		ret = max77693_get_charge_type(regmap, &val->intval);
270 		break;
271 	case POWER_SUPPLY_PROP_HEALTH:
272 		ret = max77693_get_battery_health(regmap, &val->intval);
273 		break;
274 	case POWER_SUPPLY_PROP_PRESENT:
275 		ret = max77693_get_present(regmap, &val->intval);
276 		break;
277 	case POWER_SUPPLY_PROP_ONLINE:
278 		ret = max77693_get_online(regmap, &val->intval);
279 		break;
280 	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
281 		ret = max77693_get_input_current_limit(regmap, &val->intval);
282 		break;
283 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
284 		ret = max77693_get_fast_charge_current(regmap, &val->intval);
285 		break;
286 	case POWER_SUPPLY_PROP_MODEL_NAME:
287 		val->strval = max77693_charger_model;
288 		break;
289 	case POWER_SUPPLY_PROP_MANUFACTURER:
290 		val->strval = max77693_charger_manufacturer;
291 		break;
292 	default:
293 		return -EINVAL;
294 	}
295 
296 	return ret;
297 }
298 
299 static const struct power_supply_desc max77693_charger_desc = {
300 	.name		= MAX77693_CHARGER_NAME,
301 	.type		= POWER_SUPPLY_TYPE_BATTERY,
302 	.properties	= max77693_charger_props,
303 	.num_properties	= ARRAY_SIZE(max77693_charger_props),
304 	.get_property	= max77693_charger_get_property,
305 };
306 
device_attr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count,int (* fn)(struct max77693_charger *,unsigned long))307 static ssize_t device_attr_store(struct device *dev,
308 		struct device_attribute *attr, const char *buf, size_t count,
309 		int (*fn)(struct max77693_charger *, unsigned long))
310 {
311 	struct max77693_charger *chg = dev_get_drvdata(dev);
312 	unsigned long val;
313 	int ret;
314 
315 	ret = kstrtoul(buf, 10, &val);
316 	if (ret)
317 		return ret;
318 
319 	ret = fn(chg, val);
320 	if (ret)
321 		return ret;
322 
323 	return count;
324 }
325 
fast_charge_timer_show(struct device * dev,struct device_attribute * attr,char * buf)326 static ssize_t fast_charge_timer_show(struct device *dev,
327 		struct device_attribute *attr, char *buf)
328 {
329 	struct max77693_charger *chg = dev_get_drvdata(dev);
330 	unsigned int data, val;
331 	int ret;
332 
333 	ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_01,
334 			&data);
335 	if (ret < 0)
336 		return ret;
337 
338 	data &= CHG_CNFG_01_FCHGTIME_MASK;
339 	data >>= CHG_CNFG_01_FCHGTIME_SHIFT;
340 	switch (data) {
341 	case 0x1 ... 0x7:
342 		/* Starting from 4 hours, step by 2 hours */
343 		val = 4 + (data - 1) * 2;
344 		break;
345 	case 0x0:
346 	default:
347 		val = 0;
348 		break;
349 	}
350 
351 	return sysfs_emit(buf, "%u\n", val);
352 }
353 
max77693_set_fast_charge_timer(struct max77693_charger * chg,unsigned long hours)354 static int max77693_set_fast_charge_timer(struct max77693_charger *chg,
355 		unsigned long hours)
356 {
357 	unsigned int data;
358 
359 	/*
360 	 * 0x00 - disable
361 	 * 0x01 - 4h
362 	 * 0x02 - 6h
363 	 * ...
364 	 * 0x07 - 16h
365 	 * Round down odd values.
366 	 */
367 	switch (hours) {
368 	case 4 ... 16:
369 		data = (hours - 4) / 2 + 1;
370 		break;
371 	case 0:
372 		/* Disable */
373 		data = 0;
374 		break;
375 	default:
376 		return -EINVAL;
377 	}
378 	data <<= CHG_CNFG_01_FCHGTIME_SHIFT;
379 
380 	return regmap_update_bits(chg->max77693->regmap,
381 			MAX77693_CHG_REG_CHG_CNFG_01,
382 			CHG_CNFG_01_FCHGTIME_MASK, data);
383 }
384 
fast_charge_timer_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)385 static ssize_t fast_charge_timer_store(struct device *dev,
386 		struct device_attribute *attr, const char *buf, size_t count)
387 {
388 	return device_attr_store(dev, attr, buf, count,
389 			max77693_set_fast_charge_timer);
390 }
391 
top_off_threshold_current_show(struct device * dev,struct device_attribute * attr,char * buf)392 static ssize_t top_off_threshold_current_show(struct device *dev,
393 		struct device_attribute *attr, char *buf)
394 {
395 	struct max77693_charger *chg = dev_get_drvdata(dev);
396 	unsigned int data, val;
397 	int ret;
398 
399 	ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
400 			&data);
401 	if (ret < 0)
402 		return ret;
403 
404 	data &= CHG_CNFG_03_TOITH_MASK;
405 	data >>= CHG_CNFG_03_TOITH_SHIFT;
406 
407 	if (data <= 0x04)
408 		val = 100000 + data * 25000;
409 	else
410 		val = data * 50000;
411 
412 	return sysfs_emit(buf, "%u\n", val);
413 }
414 
max77693_set_top_off_threshold_current(struct max77693_charger * chg,unsigned long uamp)415 static int max77693_set_top_off_threshold_current(struct max77693_charger *chg,
416 		unsigned long uamp)
417 {
418 	unsigned int data;
419 
420 	if (uamp < 100000 || uamp > 350000)
421 		return -EINVAL;
422 
423 	if (uamp <= 200000)
424 		data = (uamp - 100000) / 25000;
425 	else
426 		/* (200000, 350000> */
427 		data = uamp / 50000;
428 
429 	data <<= CHG_CNFG_03_TOITH_SHIFT;
430 
431 	return regmap_update_bits(chg->max77693->regmap,
432 			MAX77693_CHG_REG_CHG_CNFG_03,
433 			CHG_CNFG_03_TOITH_MASK, data);
434 }
435 
top_off_threshold_current_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)436 static ssize_t top_off_threshold_current_store(struct device *dev,
437 		struct device_attribute *attr, const char *buf, size_t count)
438 {
439 	return device_attr_store(dev, attr, buf, count,
440 			max77693_set_top_off_threshold_current);
441 }
442 
top_off_timer_show(struct device * dev,struct device_attribute * attr,char * buf)443 static ssize_t top_off_timer_show(struct device *dev,
444 		struct device_attribute *attr, char *buf)
445 {
446 	struct max77693_charger *chg = dev_get_drvdata(dev);
447 	unsigned int data, val;
448 	int ret;
449 
450 	ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
451 			&data);
452 	if (ret < 0)
453 		return ret;
454 
455 	data &= CHG_CNFG_03_TOTIME_MASK;
456 	data >>= CHG_CNFG_03_TOTIME_SHIFT;
457 
458 	val = data * 10;
459 
460 	return sysfs_emit(buf, "%u\n", val);
461 }
462 
max77693_set_top_off_timer(struct max77693_charger * chg,unsigned long minutes)463 static int max77693_set_top_off_timer(struct max77693_charger *chg,
464 		unsigned long minutes)
465 {
466 	unsigned int data;
467 
468 	if (minutes > 70)
469 		return -EINVAL;
470 
471 	data = minutes / 10;
472 	data <<= CHG_CNFG_03_TOTIME_SHIFT;
473 
474 	return regmap_update_bits(chg->max77693->regmap,
475 			MAX77693_CHG_REG_CHG_CNFG_03,
476 			CHG_CNFG_03_TOTIME_MASK, data);
477 }
478 
top_off_timer_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)479 static ssize_t top_off_timer_store(struct device *dev,
480 		struct device_attribute *attr, const char *buf, size_t count)
481 {
482 	return device_attr_store(dev, attr, buf, count,
483 			max77693_set_top_off_timer);
484 }
485 
486 static DEVICE_ATTR_RW(fast_charge_timer);
487 static DEVICE_ATTR_RW(top_off_threshold_current);
488 static DEVICE_ATTR_RW(top_off_timer);
489 
max77693_set_constant_volt(struct max77693_charger * chg,unsigned int uvolt)490 static int max77693_set_constant_volt(struct max77693_charger *chg,
491 		unsigned int uvolt)
492 {
493 	unsigned int data;
494 
495 	/*
496 	 * 0x00 - 3.650 V
497 	 * 0x01 - 3.675 V
498 	 * ...
499 	 * 0x1b - 4.325 V
500 	 * 0x1c - 4.340 V
501 	 * 0x1d - 4.350 V
502 	 * 0x1e - 4.375 V
503 	 * 0x1f - 4.400 V
504 	 */
505 	if (uvolt >= 3650000 && uvolt < 4340000)
506 		data = (uvolt - 3650000) / 25000;
507 	else if (uvolt >= 4340000 && uvolt < 4350000)
508 		data = 0x1c;
509 	else if (uvolt >= 4350000 && uvolt <= 4400000)
510 		data = 0x1d + (uvolt - 4350000) / 25000;
511 	else {
512 		dev_err(chg->dev, "Wrong value for charging constant voltage\n");
513 		return -EINVAL;
514 	}
515 
516 	data <<= CHG_CNFG_04_CHGCVPRM_SHIFT;
517 
518 	dev_dbg(chg->dev, "Charging constant voltage: %u (0x%x)\n", uvolt,
519 			data);
520 
521 	return regmap_update_bits(chg->max77693->regmap,
522 			MAX77693_CHG_REG_CHG_CNFG_04,
523 			CHG_CNFG_04_CHGCVPRM_MASK, data);
524 }
525 
max77693_set_min_system_volt(struct max77693_charger * chg,unsigned int uvolt)526 static int max77693_set_min_system_volt(struct max77693_charger *chg,
527 		unsigned int uvolt)
528 {
529 	unsigned int data;
530 
531 	if (uvolt < 3000000 || uvolt > 3700000) {
532 		dev_err(chg->dev, "Wrong value for minimum system regulation voltage\n");
533 		return -EINVAL;
534 	}
535 
536 	data = (uvolt - 3000000) / 100000;
537 
538 	data <<= CHG_CNFG_04_MINVSYS_SHIFT;
539 
540 	dev_dbg(chg->dev, "Minimum system regulation voltage: %u (0x%x)\n",
541 			uvolt, data);
542 
543 	return regmap_update_bits(chg->max77693->regmap,
544 			MAX77693_CHG_REG_CHG_CNFG_04,
545 			CHG_CNFG_04_MINVSYS_MASK, data);
546 }
547 
max77693_set_thermal_regulation_temp(struct max77693_charger * chg,unsigned int cels)548 static int max77693_set_thermal_regulation_temp(struct max77693_charger *chg,
549 		unsigned int cels)
550 {
551 	unsigned int data;
552 
553 	switch (cels) {
554 	case 70:
555 	case 85:
556 	case 100:
557 	case 115:
558 		data = (cels - 70) / 15;
559 		break;
560 	default:
561 		dev_err(chg->dev, "Wrong value for thermal regulation loop temperature\n");
562 		return -EINVAL;
563 	}
564 
565 	data <<= CHG_CNFG_07_REGTEMP_SHIFT;
566 
567 	dev_dbg(chg->dev, "Thermal regulation loop temperature: %u (0x%x)\n",
568 			cels, data);
569 
570 	return regmap_update_bits(chg->max77693->regmap,
571 			MAX77693_CHG_REG_CHG_CNFG_07,
572 			CHG_CNFG_07_REGTEMP_MASK, data);
573 }
574 
max77693_set_batttery_overcurrent(struct max77693_charger * chg,unsigned int uamp)575 static int max77693_set_batttery_overcurrent(struct max77693_charger *chg,
576 		unsigned int uamp)
577 {
578 	unsigned int data;
579 
580 	if (uamp && (uamp < 2000000 || uamp > 3500000)) {
581 		dev_err(chg->dev, "Wrong value for battery overcurrent\n");
582 		return -EINVAL;
583 	}
584 
585 	if (uamp)
586 		data = ((uamp - 2000000) / 250000) + 1;
587 	else
588 		data = 0; /* disable */
589 
590 	data <<= CHG_CNFG_12_B2SOVRC_SHIFT;
591 
592 	dev_dbg(chg->dev, "Battery overcurrent: %u (0x%x)\n", uamp, data);
593 
594 	return regmap_update_bits(chg->max77693->regmap,
595 			MAX77693_CHG_REG_CHG_CNFG_12,
596 			CHG_CNFG_12_B2SOVRC_MASK, data);
597 }
598 
max77693_set_charge_input_threshold_volt(struct max77693_charger * chg,unsigned int uvolt)599 static int max77693_set_charge_input_threshold_volt(struct max77693_charger *chg,
600 		unsigned int uvolt)
601 {
602 	unsigned int data;
603 
604 	switch (uvolt) {
605 	case 4300000:
606 		data = 0x0;
607 		break;
608 	case 4700000:
609 	case 4800000:
610 	case 4900000:
611 		data = (uvolt - 4700000) / 100000;
612 		break;
613 	default:
614 		dev_err(chg->dev, "Wrong value for charge input voltage regulation threshold\n");
615 		return -EINVAL;
616 	}
617 
618 	data <<= CHG_CNFG_12_VCHGINREG_SHIFT;
619 
620 	dev_dbg(chg->dev, "Charge input voltage regulation threshold: %u (0x%x)\n",
621 			uvolt, data);
622 
623 	return regmap_update_bits(chg->max77693->regmap,
624 			MAX77693_CHG_REG_CHG_CNFG_12,
625 			CHG_CNFG_12_VCHGINREG_MASK, data);
626 }
627 
628 /*
629  * Sets charger registers to proper and safe default values.
630  */
max77693_reg_init(struct max77693_charger * chg)631 static int max77693_reg_init(struct max77693_charger *chg)
632 {
633 	int ret;
634 	unsigned int data;
635 
636 	/* Unlock charger register protection */
637 	data = (0x3 << CHG_CNFG_06_CHGPROT_SHIFT);
638 	ret = regmap_update_bits(chg->max77693->regmap,
639 				MAX77693_CHG_REG_CHG_CNFG_06,
640 				CHG_CNFG_06_CHGPROT_MASK, data);
641 	if (ret) {
642 		dev_err(chg->dev, "Error unlocking registers: %d\n", ret);
643 		return ret;
644 	}
645 
646 	ret = max77693_set_fast_charge_timer(chg, DEFAULT_FAST_CHARGE_TIMER);
647 	if (ret)
648 		return ret;
649 
650 	ret = max77693_set_top_off_threshold_current(chg,
651 			DEFAULT_TOP_OFF_THRESHOLD_CURRENT);
652 	if (ret)
653 		return ret;
654 
655 	ret = max77693_set_top_off_timer(chg, DEFAULT_TOP_OFF_TIMER);
656 	if (ret)
657 		return ret;
658 
659 	ret = max77693_set_constant_volt(chg, chg->constant_volt);
660 	if (ret)
661 		return ret;
662 
663 	ret = max77693_set_min_system_volt(chg, chg->min_system_volt);
664 	if (ret)
665 		return ret;
666 
667 	ret = max77693_set_thermal_regulation_temp(chg,
668 			chg->thermal_regulation_temp);
669 	if (ret)
670 		return ret;
671 
672 	ret = max77693_set_batttery_overcurrent(chg, chg->batttery_overcurrent);
673 	if (ret)
674 		return ret;
675 
676 	return max77693_set_charge_input_threshold_volt(chg,
677 			chg->charge_input_threshold_volt);
678 }
679 
680 #ifdef CONFIG_OF
max77693_dt_init(struct device * dev,struct max77693_charger * chg)681 static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
682 {
683 	struct device_node *np = dev->of_node;
684 
685 	if (!np) {
686 		dev_err(dev, "no charger OF node\n");
687 		return -EINVAL;
688 	}
689 
690 	if (of_property_read_u32(np, "maxim,constant-microvolt",
691 			&chg->constant_volt))
692 		chg->constant_volt = DEFAULT_CONSTANT_VOLT;
693 
694 	if (of_property_read_u32(np, "maxim,min-system-microvolt",
695 			&chg->min_system_volt))
696 		chg->min_system_volt = DEFAULT_MIN_SYSTEM_VOLT;
697 
698 	if (of_property_read_u32(np, "maxim,thermal-regulation-celsius",
699 			&chg->thermal_regulation_temp))
700 		chg->thermal_regulation_temp = DEFAULT_THERMAL_REGULATION_TEMP;
701 
702 	if (of_property_read_u32(np, "maxim,battery-overcurrent-microamp",
703 			&chg->batttery_overcurrent))
704 		chg->batttery_overcurrent = DEFAULT_BATTERY_OVERCURRENT;
705 
706 	if (of_property_read_u32(np, "maxim,charge-input-threshold-microvolt",
707 			&chg->charge_input_threshold_volt))
708 		chg->charge_input_threshold_volt =
709 			DEFAULT_CHARGER_INPUT_THRESHOLD_VOLT;
710 
711 	return 0;
712 }
713 #else /* CONFIG_OF */
max77693_dt_init(struct device * dev,struct max77693_charger * chg)714 static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
715 {
716 	return 0;
717 }
718 #endif /* CONFIG_OF */
719 
max77693_charger_probe(struct platform_device * pdev)720 static int max77693_charger_probe(struct platform_device *pdev)
721 {
722 	struct max77693_charger *chg;
723 	struct power_supply_config psy_cfg = {};
724 	struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
725 	int ret;
726 
727 	chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL);
728 	if (!chg)
729 		return -ENOMEM;
730 
731 	platform_set_drvdata(pdev, chg);
732 	chg->dev = &pdev->dev;
733 	chg->max77693 = max77693;
734 
735 	ret = max77693_dt_init(&pdev->dev, chg);
736 	if (ret)
737 		return ret;
738 
739 	ret = max77693_reg_init(chg);
740 	if (ret)
741 		return ret;
742 
743 	psy_cfg.drv_data = chg;
744 
745 	ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer);
746 	if (ret) {
747 		dev_err(&pdev->dev, "failed: create fast charge timer sysfs entry\n");
748 		goto err;
749 	}
750 
751 	ret = device_create_file(&pdev->dev,
752 			&dev_attr_top_off_threshold_current);
753 	if (ret) {
754 		dev_err(&pdev->dev, "failed: create top off current sysfs entry\n");
755 		goto err;
756 	}
757 
758 	ret = device_create_file(&pdev->dev, &dev_attr_top_off_timer);
759 	if (ret) {
760 		dev_err(&pdev->dev, "failed: create top off timer sysfs entry\n");
761 		goto err;
762 	}
763 
764 	chg->charger = devm_power_supply_register(&pdev->dev,
765 						  &max77693_charger_desc,
766 						  &psy_cfg);
767 	if (IS_ERR(chg->charger)) {
768 		dev_err(&pdev->dev, "failed: power supply register\n");
769 		ret = PTR_ERR(chg->charger);
770 		goto err;
771 	}
772 
773 	return 0;
774 
775 err:
776 	device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
777 	device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
778 	device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
779 
780 	return ret;
781 }
782 
max77693_charger_remove(struct platform_device * pdev)783 static void max77693_charger_remove(struct platform_device *pdev)
784 {
785 	device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
786 	device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
787 	device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
788 }
789 
790 static const struct platform_device_id max77693_charger_id[] = {
791 	{ "max77693-charger", 0, },
792 	{ }
793 };
794 MODULE_DEVICE_TABLE(platform, max77693_charger_id);
795 
796 static struct platform_driver max77693_charger_driver = {
797 	.driver = {
798 		.name	= "max77693-charger",
799 	},
800 	.probe		= max77693_charger_probe,
801 	.remove		= max77693_charger_remove,
802 	.id_table	= max77693_charger_id,
803 };
804 module_platform_driver(max77693_charger_driver);
805 
806 MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
807 MODULE_DESCRIPTION("Maxim 77693 charger driver");
808 MODULE_LICENSE("GPL");
809