1 /*
2  * TI LP8788 MFD - battery charger driver
3  *
4  * Copyright 2012 Texas Instruments
5  *
6  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  */
13 
14 #include <linux/err.h>
15 #include <linux/iio/consumer.h>
16 #include <linux/interrupt.h>
17 #include <linux/irqdomain.h>
18 #include <linux/mfd/lp8788.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/power_supply.h>
22 #include <linux/slab.h>
23 #include <linux/workqueue.h>
24 
25 /* register address */
26 #define LP8788_CHG_STATUS		0x07
27 #define LP8788_CHG_IDCIN		0x13
28 #define LP8788_CHG_IBATT		0x14
29 #define LP8788_CHG_VTERM		0x15
30 #define LP8788_CHG_EOC			0x16
31 
32 /* mask/shift bits */
33 #define LP8788_CHG_INPUT_STATE_M	0x03	/* Addr 07h */
34 #define LP8788_CHG_STATE_M		0x3C
35 #define LP8788_CHG_STATE_S		2
36 #define LP8788_NO_BATT_M		BIT(6)
37 #define LP8788_BAD_BATT_M		BIT(7)
38 #define LP8788_CHG_IBATT_M		0x1F	/* Addr 14h */
39 #define LP8788_CHG_VTERM_M		0x0F	/* Addr 15h */
40 #define LP8788_CHG_EOC_LEVEL_M		0x30	/* Addr 16h */
41 #define LP8788_CHG_EOC_LEVEL_S		4
42 #define LP8788_CHG_EOC_TIME_M		0x0E
43 #define LP8788_CHG_EOC_TIME_S		1
44 #define LP8788_CHG_EOC_MODE_M		BIT(0)
45 
46 #define LP8788_CHARGER_NAME		"charger"
47 #define LP8788_BATTERY_NAME		"main_batt"
48 
49 #define LP8788_CHG_START		0x11
50 #define LP8788_CHG_END			0x1C
51 
52 #define LP8788_ISEL_MAX			23
53 #define LP8788_ISEL_STEP		50
54 #define LP8788_VTERM_MIN		4100
55 #define LP8788_VTERM_STEP		25
56 #define LP8788_MAX_BATT_CAPACITY	100
57 #define LP8788_MAX_CHG_IRQS		11
58 
59 enum lp8788_charging_state {
60 	LP8788_OFF,
61 	LP8788_WARM_UP,
62 	LP8788_LOW_INPUT = 0x3,
63 	LP8788_PRECHARGE,
64 	LP8788_CC,
65 	LP8788_CV,
66 	LP8788_MAINTENANCE,
67 	LP8788_BATTERY_FAULT,
68 	LP8788_SYSTEM_SUPPORT = 0xC,
69 	LP8788_HIGH_CURRENT = 0xF,
70 	LP8788_MAX_CHG_STATE,
71 };
72 
73 enum lp8788_charger_adc_sel {
74 	LP8788_VBATT,
75 	LP8788_BATT_TEMP,
76 	LP8788_NUM_CHG_ADC,
77 };
78 
79 enum lp8788_charger_input_state {
80 	LP8788_SYSTEM_SUPPLY = 1,
81 	LP8788_FULL_FUNCTION,
82 };
83 
84 /*
85  * struct lp8788_chg_irq
86  * @which        : lp8788 interrupt id
87  * @virq         : Linux IRQ number from irq_domain
88  */
89 struct lp8788_chg_irq {
90 	enum lp8788_int_id which;
91 	int virq;
92 };
93 
94 /*
95  * struct lp8788_charger
96  * @lp           : used for accessing the registers of mfd lp8788 device
97  * @charger      : power supply driver for the battery charger
98  * @battery      : power supply driver for the battery
99  * @charger_work : work queue for charger input interrupts
100  * @chan         : iio channels for getting adc values
101  *                 eg) battery voltage, capacity and temperature
102  * @irqs         : charger dedicated interrupts
103  * @num_irqs     : total numbers of charger interrupts
104  * @pdata        : charger platform specific data
105  */
106 struct lp8788_charger {
107 	struct lp8788 *lp;
108 	struct power_supply *charger;
109 	struct power_supply *battery;
110 	struct work_struct charger_work;
111 	struct iio_channel *chan[LP8788_NUM_CHG_ADC];
112 	struct lp8788_chg_irq irqs[LP8788_MAX_CHG_IRQS];
113 	int num_irqs;
114 	struct lp8788_charger_platform_data *pdata;
115 };
116 
117 static char *battery_supplied_to[] = {
118 	LP8788_BATTERY_NAME,
119 };
120 
121 static enum power_supply_property lp8788_charger_prop[] = {
122 	POWER_SUPPLY_PROP_ONLINE,
123 	POWER_SUPPLY_PROP_CURRENT_MAX,
124 };
125 
126 static enum power_supply_property lp8788_battery_prop[] = {
127 	POWER_SUPPLY_PROP_STATUS,
128 	POWER_SUPPLY_PROP_HEALTH,
129 	POWER_SUPPLY_PROP_PRESENT,
130 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
131 	POWER_SUPPLY_PROP_CAPACITY,
132 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
133 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
134 	POWER_SUPPLY_PROP_TEMP,
135 };
136 
137 static bool lp8788_is_charger_detected(struct lp8788_charger *pchg)
138 {
139 	u8 data;
140 
141 	lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
142 	data &= LP8788_CHG_INPUT_STATE_M;
143 
144 	return data == LP8788_SYSTEM_SUPPLY || data == LP8788_FULL_FUNCTION;
145 }
146 
147 static int lp8788_charger_get_property(struct power_supply *psy,
148 					enum power_supply_property psp,
149 					union power_supply_propval *val)
150 {
151 	struct lp8788_charger *pchg = dev_get_drvdata(psy->dev.parent);
152 	u8 read;
153 
154 	switch (psp) {
155 	case POWER_SUPPLY_PROP_ONLINE:
156 		val->intval = lp8788_is_charger_detected(pchg);
157 		break;
158 	case POWER_SUPPLY_PROP_CURRENT_MAX:
159 		lp8788_read_byte(pchg->lp, LP8788_CHG_IDCIN, &read);
160 		val->intval = LP8788_ISEL_STEP *
161 				(min_t(int, read, LP8788_ISEL_MAX) + 1);
162 		break;
163 	default:
164 		return -EINVAL;
165 	}
166 
167 	return 0;
168 }
169 
170 static int lp8788_get_battery_status(struct lp8788_charger *pchg,
171 				union power_supply_propval *val)
172 {
173 	enum lp8788_charging_state state;
174 	u8 data;
175 	int ret;
176 
177 	ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
178 	if (ret)
179 		return ret;
180 
181 	state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;
182 	switch (state) {
183 	case LP8788_OFF:
184 		val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
185 		break;
186 	case LP8788_PRECHARGE:
187 	case LP8788_CC:
188 	case LP8788_CV:
189 	case LP8788_HIGH_CURRENT:
190 		val->intval = POWER_SUPPLY_STATUS_CHARGING;
191 		break;
192 	case LP8788_MAINTENANCE:
193 		val->intval = POWER_SUPPLY_STATUS_FULL;
194 		break;
195 	default:
196 		val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
197 		break;
198 	}
199 
200 	return 0;
201 }
202 
203 static int lp8788_get_battery_health(struct lp8788_charger *pchg,
204 				union power_supply_propval *val)
205 {
206 	u8 data;
207 	int ret;
208 
209 	ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
210 	if (ret)
211 		return ret;
212 
213 	if (data & LP8788_NO_BATT_M)
214 		val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
215 	else if (data & LP8788_BAD_BATT_M)
216 		val->intval = POWER_SUPPLY_HEALTH_DEAD;
217 	else
218 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
219 
220 	return 0;
221 }
222 
223 static int lp8788_get_battery_present(struct lp8788_charger *pchg,
224 				union power_supply_propval *val)
225 {
226 	u8 data;
227 	int ret;
228 
229 	ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
230 	if (ret)
231 		return ret;
232 
233 	val->intval = !(data & LP8788_NO_BATT_M);
234 	return 0;
235 }
236 
237 static int lp8788_get_vbatt_adc(struct lp8788_charger *pchg, int *result)
238 {
239 	struct iio_channel *channel = pchg->chan[LP8788_VBATT];
240 
241 	if (!channel)
242 		return -EINVAL;
243 
244 	return iio_read_channel_processed(channel, result);
245 }
246 
247 static int lp8788_get_battery_voltage(struct lp8788_charger *pchg,
248 				union power_supply_propval *val)
249 {
250 	return lp8788_get_vbatt_adc(pchg, &val->intval);
251 }
252 
253 static int lp8788_get_battery_capacity(struct lp8788_charger *pchg,
254 				union power_supply_propval *val)
255 {
256 	struct lp8788 *lp = pchg->lp;
257 	struct lp8788_charger_platform_data *pdata = pchg->pdata;
258 	unsigned int max_vbatt;
259 	int vbatt;
260 	enum lp8788_charging_state state;
261 	u8 data;
262 	int ret;
263 
264 	if (!pdata)
265 		return -EINVAL;
266 
267 	max_vbatt = pdata->max_vbatt_mv;
268 	if (max_vbatt == 0)
269 		return -EINVAL;
270 
271 	ret = lp8788_read_byte(lp, LP8788_CHG_STATUS, &data);
272 	if (ret)
273 		return ret;
274 
275 	state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;
276 
277 	if (state == LP8788_MAINTENANCE) {
278 		val->intval = LP8788_MAX_BATT_CAPACITY;
279 	} else {
280 		ret = lp8788_get_vbatt_adc(pchg, &vbatt);
281 		if (ret)
282 			return ret;
283 
284 		val->intval = (vbatt * LP8788_MAX_BATT_CAPACITY) / max_vbatt;
285 		val->intval = min(val->intval, LP8788_MAX_BATT_CAPACITY);
286 	}
287 
288 	return 0;
289 }
290 
291 static int lp8788_get_battery_temperature(struct lp8788_charger *pchg,
292 				union power_supply_propval *val)
293 {
294 	struct iio_channel *channel = pchg->chan[LP8788_BATT_TEMP];
295 	int result;
296 	int ret;
297 
298 	if (!channel)
299 		return -EINVAL;
300 
301 	ret = iio_read_channel_processed(channel, &result);
302 	if (ret < 0)
303 		return -EINVAL;
304 
305 	/* unit: 0.1 'C */
306 	val->intval = result * 10;
307 
308 	return 0;
309 }
310 
311 static int lp8788_get_battery_charging_current(struct lp8788_charger *pchg,
312 				union power_supply_propval *val)
313 {
314 	u8 read;
315 
316 	lp8788_read_byte(pchg->lp, LP8788_CHG_IBATT, &read);
317 	read &= LP8788_CHG_IBATT_M;
318 	val->intval = LP8788_ISEL_STEP *
319 			(min_t(int, read, LP8788_ISEL_MAX) + 1);
320 
321 	return 0;
322 }
323 
324 static int lp8788_get_charging_termination_voltage(struct lp8788_charger *pchg,
325 				union power_supply_propval *val)
326 {
327 	u8 read;
328 
329 	lp8788_read_byte(pchg->lp, LP8788_CHG_VTERM, &read);
330 	read &= LP8788_CHG_VTERM_M;
331 	val->intval = LP8788_VTERM_MIN + LP8788_VTERM_STEP * read;
332 
333 	return 0;
334 }
335 
336 static int lp8788_battery_get_property(struct power_supply *psy,
337 					enum power_supply_property psp,
338 					union power_supply_propval *val)
339 {
340 	struct lp8788_charger *pchg = dev_get_drvdata(psy->dev.parent);
341 
342 	switch (psp) {
343 	case POWER_SUPPLY_PROP_STATUS:
344 		return lp8788_get_battery_status(pchg, val);
345 	case POWER_SUPPLY_PROP_HEALTH:
346 		return lp8788_get_battery_health(pchg, val);
347 	case POWER_SUPPLY_PROP_PRESENT:
348 		return lp8788_get_battery_present(pchg, val);
349 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
350 		return lp8788_get_battery_voltage(pchg, val);
351 	case POWER_SUPPLY_PROP_CAPACITY:
352 		return lp8788_get_battery_capacity(pchg, val);
353 	case POWER_SUPPLY_PROP_TEMP:
354 		return lp8788_get_battery_temperature(pchg, val);
355 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
356 		return lp8788_get_battery_charging_current(pchg, val);
357 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
358 		return lp8788_get_charging_termination_voltage(pchg, val);
359 	default:
360 		return -EINVAL;
361 	}
362 }
363 
364 static inline bool lp8788_is_valid_charger_register(u8 addr)
365 {
366 	return addr >= LP8788_CHG_START && addr <= LP8788_CHG_END;
367 }
368 
369 static int lp8788_update_charger_params(struct platform_device *pdev,
370 					struct lp8788_charger *pchg)
371 {
372 	struct lp8788 *lp = pchg->lp;
373 	struct lp8788_charger_platform_data *pdata = pchg->pdata;
374 	struct lp8788_chg_param *param;
375 	int i;
376 	int ret;
377 
378 	if (!pdata || !pdata->chg_params) {
379 		dev_info(&pdev->dev, "skip updating charger parameters\n");
380 		return 0;
381 	}
382 
383 	/* settting charging parameters */
384 	for (i = 0; i < pdata->num_chg_params; i++) {
385 		param = pdata->chg_params + i;
386 
387 		if (lp8788_is_valid_charger_register(param->addr)) {
388 			ret = lp8788_write_byte(lp, param->addr, param->val);
389 			if (ret)
390 				return ret;
391 		}
392 	}
393 
394 	return 0;
395 }
396 
397 static const struct power_supply_desc lp8788_psy_charger_desc = {
398 	.name		= LP8788_CHARGER_NAME,
399 	.type		= POWER_SUPPLY_TYPE_MAINS,
400 	.properties	= lp8788_charger_prop,
401 	.num_properties	= ARRAY_SIZE(lp8788_charger_prop),
402 	.get_property	= lp8788_charger_get_property,
403 };
404 
405 static const struct power_supply_desc lp8788_psy_battery_desc = {
406 	.name		= LP8788_BATTERY_NAME,
407 	.type		= POWER_SUPPLY_TYPE_BATTERY,
408 	.properties	= lp8788_battery_prop,
409 	.num_properties	= ARRAY_SIZE(lp8788_battery_prop),
410 	.get_property	= lp8788_battery_get_property,
411 };
412 
413 static int lp8788_psy_register(struct platform_device *pdev,
414 				struct lp8788_charger *pchg)
415 {
416 	struct power_supply_config charger_cfg = {};
417 
418 	charger_cfg.supplied_to = battery_supplied_to;
419 	charger_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
420 
421 	pchg->charger = power_supply_register(&pdev->dev,
422 					      &lp8788_psy_charger_desc,
423 					      &charger_cfg);
424 	if (IS_ERR(pchg->charger))
425 		return -EPERM;
426 
427 	pchg->battery = power_supply_register(&pdev->dev,
428 					      &lp8788_psy_battery_desc, NULL);
429 	if (IS_ERR(pchg->battery)) {
430 		power_supply_unregister(pchg->charger);
431 		return -EPERM;
432 	}
433 
434 	return 0;
435 }
436 
437 static void lp8788_psy_unregister(struct lp8788_charger *pchg)
438 {
439 	power_supply_unregister(pchg->battery);
440 	power_supply_unregister(pchg->charger);
441 }
442 
443 static void lp8788_charger_event(struct work_struct *work)
444 {
445 	struct lp8788_charger *pchg =
446 		container_of(work, struct lp8788_charger, charger_work);
447 	struct lp8788_charger_platform_data *pdata = pchg->pdata;
448 	enum lp8788_charger_event event = lp8788_is_charger_detected(pchg);
449 
450 	pdata->charger_event(pchg->lp, event);
451 }
452 
453 static bool lp8788_find_irq_id(struct lp8788_charger *pchg, int virq, int *id)
454 {
455 	bool found = false;
456 	int i;
457 
458 	for (i = 0; i < pchg->num_irqs; i++) {
459 		if (pchg->irqs[i].virq == virq) {
460 			*id = pchg->irqs[i].which;
461 			found = true;
462 			break;
463 		}
464 	}
465 
466 	return found;
467 }
468 
469 static irqreturn_t lp8788_charger_irq_thread(int virq, void *ptr)
470 {
471 	struct lp8788_charger *pchg = ptr;
472 	struct lp8788_charger_platform_data *pdata = pchg->pdata;
473 	int id = -1;
474 
475 	if (!lp8788_find_irq_id(pchg, virq, &id))
476 		return IRQ_NONE;
477 
478 	switch (id) {
479 	case LP8788_INT_CHG_INPUT_STATE:
480 	case LP8788_INT_CHG_STATE:
481 	case LP8788_INT_EOC:
482 	case LP8788_INT_BATT_LOW:
483 	case LP8788_INT_NO_BATT:
484 		power_supply_changed(pchg->charger);
485 		power_supply_changed(pchg->battery);
486 		break;
487 	default:
488 		break;
489 	}
490 
491 	/* report charger dectection event if used */
492 	if (!pdata)
493 		goto irq_handled;
494 
495 	if (pdata->charger_event && id == LP8788_INT_CHG_INPUT_STATE)
496 		schedule_work(&pchg->charger_work);
497 
498 irq_handled:
499 	return IRQ_HANDLED;
500 }
501 
502 static int lp8788_set_irqs(struct platform_device *pdev,
503 			struct lp8788_charger *pchg, const char *name)
504 {
505 	struct resource *r;
506 	struct irq_domain *irqdm = pchg->lp->irqdm;
507 	int irq_start;
508 	int irq_end;
509 	int virq;
510 	int nr_irq;
511 	int i;
512 	int ret;
513 
514 	/* no error even if no irq resource */
515 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, name);
516 	if (!r)
517 		return 0;
518 
519 	irq_start = r->start;
520 	irq_end = r->end;
521 
522 	for (i = irq_start; i <= irq_end; i++) {
523 		nr_irq = pchg->num_irqs;
524 
525 		virq = irq_create_mapping(irqdm, i);
526 		pchg->irqs[nr_irq].virq = virq;
527 		pchg->irqs[nr_irq].which = i;
528 		pchg->num_irqs++;
529 
530 		ret = request_threaded_irq(virq, NULL,
531 					lp8788_charger_irq_thread,
532 					0, name, pchg);
533 		if (ret)
534 			break;
535 	}
536 
537 	if (i <= irq_end)
538 		goto err_free_irq;
539 
540 	return 0;
541 
542 err_free_irq:
543 	for (i = 0; i < pchg->num_irqs; i++)
544 		free_irq(pchg->irqs[i].virq, pchg);
545 	return ret;
546 }
547 
548 static int lp8788_irq_register(struct platform_device *pdev,
549 				struct lp8788_charger *pchg)
550 {
551 	const char *name[] = {
552 		LP8788_CHG_IRQ, LP8788_PRSW_IRQ, LP8788_BATT_IRQ
553 	};
554 	int i;
555 	int ret;
556 
557 	INIT_WORK(&pchg->charger_work, lp8788_charger_event);
558 	pchg->num_irqs = 0;
559 
560 	for (i = 0; i < ARRAY_SIZE(name); i++) {
561 		ret = lp8788_set_irqs(pdev, pchg, name[i]);
562 		if (ret) {
563 			dev_warn(&pdev->dev, "irq setup failed: %s\n", name[i]);
564 			return ret;
565 		}
566 	}
567 
568 	if (pchg->num_irqs > LP8788_MAX_CHG_IRQS) {
569 		dev_err(&pdev->dev, "invalid total number of irqs: %d\n",
570 			pchg->num_irqs);
571 		return -EINVAL;
572 	}
573 
574 
575 	return 0;
576 }
577 
578 static void lp8788_irq_unregister(struct platform_device *pdev,
579 				  struct lp8788_charger *pchg)
580 {
581 	int i;
582 	int irq;
583 
584 	for (i = 0; i < pchg->num_irqs; i++) {
585 		irq = pchg->irqs[i].virq;
586 		if (!irq)
587 			continue;
588 
589 		free_irq(irq, pchg);
590 	}
591 }
592 
593 static void lp8788_setup_adc_channel(struct device *dev,
594 				struct lp8788_charger *pchg)
595 {
596 	struct lp8788_charger_platform_data *pdata = pchg->pdata;
597 	struct iio_channel *chan;
598 
599 	if (!pdata)
600 		return;
601 
602 	/* ADC channel for battery voltage */
603 	chan = iio_channel_get(dev, pdata->adc_vbatt);
604 	pchg->chan[LP8788_VBATT] = IS_ERR(chan) ? NULL : chan;
605 
606 	/* ADC channel for battery temperature */
607 	chan = iio_channel_get(dev, pdata->adc_batt_temp);
608 	pchg->chan[LP8788_BATT_TEMP] = IS_ERR(chan) ? NULL : chan;
609 }
610 
611 static void lp8788_release_adc_channel(struct lp8788_charger *pchg)
612 {
613 	int i;
614 
615 	for (i = 0; i < LP8788_NUM_CHG_ADC; i++) {
616 		if (!pchg->chan[i])
617 			continue;
618 
619 		iio_channel_release(pchg->chan[i]);
620 		pchg->chan[i] = NULL;
621 	}
622 }
623 
624 static ssize_t lp8788_show_charger_status(struct device *dev,
625 				struct device_attribute *attr, char *buf)
626 {
627 	struct lp8788_charger *pchg = dev_get_drvdata(dev);
628 	enum lp8788_charging_state state;
629 	static const char * const desc[LP8788_MAX_CHG_STATE] = {
630 		[LP8788_OFF] = "CHARGER OFF",
631 		[LP8788_WARM_UP] = "WARM UP",
632 		[LP8788_LOW_INPUT] = "LOW INPUT STATE",
633 		[LP8788_PRECHARGE] = "CHARGING - PRECHARGE",
634 		[LP8788_CC] = "CHARGING - CC",
635 		[LP8788_CV] = "CHARGING - CV",
636 		[LP8788_MAINTENANCE] = "NO CHARGING - MAINTENANCE",
637 		[LP8788_BATTERY_FAULT] = "BATTERY FAULT",
638 		[LP8788_SYSTEM_SUPPORT] = "SYSTEM SUPPORT",
639 		[LP8788_HIGH_CURRENT] = "HIGH CURRENT",
640 	};
641 	u8 data;
642 
643 	lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data);
644 	state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S;
645 
646 	return scnprintf(buf, PAGE_SIZE, "%s\n", desc[state]);
647 }
648 
649 static ssize_t lp8788_show_eoc_time(struct device *dev,
650 				struct device_attribute *attr, char *buf)
651 {
652 	struct lp8788_charger *pchg = dev_get_drvdata(dev);
653 	static const char * const stime[] = {
654 		"400ms", "5min", "10min", "15min",
655 		"20min", "25min", "30min", "No timeout"
656 	};
657 	u8 val;
658 
659 	lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val);
660 	val = (val & LP8788_CHG_EOC_TIME_M) >> LP8788_CHG_EOC_TIME_S;
661 
662 	return scnprintf(buf, PAGE_SIZE, "End Of Charge Time: %s\n",
663 			stime[val]);
664 }
665 
666 static ssize_t lp8788_show_eoc_level(struct device *dev,
667 				struct device_attribute *attr, char *buf)
668 {
669 	struct lp8788_charger *pchg = dev_get_drvdata(dev);
670 	static const char * const abs_level[] = {
671 			"25mA", "49mA", "75mA", "98mA"
672 	};
673 	static const char * const relative_level[] = {
674 			"5%", "10%", "15%", "20%"
675 	};
676 	const char *level;
677 	u8 val;
678 	u8 mode;
679 
680 	lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val);
681 
682 	mode = val & LP8788_CHG_EOC_MODE_M;
683 	val = (val & LP8788_CHG_EOC_LEVEL_M) >> LP8788_CHG_EOC_LEVEL_S;
684 	level = mode ? abs_level[val] : relative_level[val];
685 
686 	return scnprintf(buf, PAGE_SIZE, "End Of Charge Level: %s\n", level);
687 }
688 
689 static DEVICE_ATTR(charger_status, S_IRUSR, lp8788_show_charger_status, NULL);
690 static DEVICE_ATTR(eoc_time, S_IRUSR, lp8788_show_eoc_time, NULL);
691 static DEVICE_ATTR(eoc_level, S_IRUSR, lp8788_show_eoc_level, NULL);
692 
693 static struct attribute *lp8788_charger_attr[] = {
694 	&dev_attr_charger_status.attr,
695 	&dev_attr_eoc_time.attr,
696 	&dev_attr_eoc_level.attr,
697 	NULL,
698 };
699 
700 static const struct attribute_group lp8788_attr_group = {
701 	.attrs = lp8788_charger_attr,
702 };
703 
704 static int lp8788_charger_probe(struct platform_device *pdev)
705 {
706 	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
707 	struct lp8788_charger *pchg;
708 	struct device *dev = &pdev->dev;
709 	int ret;
710 
711 	pchg = devm_kzalloc(dev, sizeof(struct lp8788_charger), GFP_KERNEL);
712 	if (!pchg)
713 		return -ENOMEM;
714 
715 	pchg->lp = lp;
716 	pchg->pdata = lp->pdata ? lp->pdata->chg_pdata : NULL;
717 	platform_set_drvdata(pdev, pchg);
718 
719 	ret = lp8788_update_charger_params(pdev, pchg);
720 	if (ret)
721 		return ret;
722 
723 	lp8788_setup_adc_channel(&pdev->dev, pchg);
724 
725 	ret = lp8788_psy_register(pdev, pchg);
726 	if (ret)
727 		return ret;
728 
729 	ret = sysfs_create_group(&pdev->dev.kobj, &lp8788_attr_group);
730 	if (ret) {
731 		lp8788_psy_unregister(pchg);
732 		return ret;
733 	}
734 
735 	ret = lp8788_irq_register(pdev, pchg);
736 	if (ret)
737 		dev_warn(dev, "failed to register charger irq: %d\n", ret);
738 
739 	return 0;
740 }
741 
742 static int lp8788_charger_remove(struct platform_device *pdev)
743 {
744 	struct lp8788_charger *pchg = platform_get_drvdata(pdev);
745 
746 	flush_work(&pchg->charger_work);
747 	lp8788_irq_unregister(pdev, pchg);
748 	sysfs_remove_group(&pdev->dev.kobj, &lp8788_attr_group);
749 	lp8788_psy_unregister(pchg);
750 	lp8788_release_adc_channel(pchg);
751 
752 	return 0;
753 }
754 
755 static struct platform_driver lp8788_charger_driver = {
756 	.probe = lp8788_charger_probe,
757 	.remove = lp8788_charger_remove,
758 	.driver = {
759 		.name = LP8788_DEV_CHARGER,
760 	},
761 };
762 module_platform_driver(lp8788_charger_driver);
763 
764 MODULE_DESCRIPTION("TI LP8788 Charger Driver");
765 MODULE_AUTHOR("Milo Kim");
766 MODULE_LICENSE("GPL");
767 MODULE_ALIAS("platform:lp8788-charger");
768