1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for LP8727 Micro/Mini USB IC with integrated charger
4  *
5  *			Copyright (C) 2011 Texas Instruments
6  *			Copyright (C) 2011 National Semiconductor
7  */
8 
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/interrupt.h>
12 #include <linux/i2c.h>
13 #include <linux/power_supply.h>
14 #include <linux/platform_data/lp8727.h>
15 #include <linux/of.h>
16 
17 #define LP8788_NUM_INTREGS	2
18 #define DEFAULT_DEBOUNCE_MSEC	270
19 
20 /* Registers */
21 #define LP8727_CTRL1		0x1
22 #define LP8727_CTRL2		0x2
23 #define LP8727_SWCTRL		0x3
24 #define LP8727_INT1		0x4
25 #define LP8727_INT2		0x5
26 #define LP8727_STATUS1		0x6
27 #define LP8727_STATUS2		0x7
28 #define LP8727_CHGCTRL2		0x9
29 
30 /* CTRL1 register */
31 #define LP8727_CP_EN		BIT(0)
32 #define LP8727_ADC_EN		BIT(1)
33 #define LP8727_ID200_EN		BIT(4)
34 
35 /* CTRL2 register */
36 #define LP8727_CHGDET_EN	BIT(1)
37 #define LP8727_INT_EN		BIT(6)
38 
39 /* SWCTRL register */
40 #define LP8727_SW_DM1_DM	(0x0 << 0)
41 #define LP8727_SW_DM1_HiZ	(0x7 << 0)
42 #define LP8727_SW_DP2_DP	(0x0 << 3)
43 #define LP8727_SW_DP2_HiZ	(0x7 << 3)
44 
45 /* INT1 register */
46 #define LP8727_IDNO		(0xF << 0)
47 #define LP8727_VBUS		BIT(4)
48 
49 /* STATUS1 register */
50 #define LP8727_CHGSTAT		(3 << 4)
51 #define LP8727_CHPORT		BIT(6)
52 #define LP8727_DCPORT		BIT(7)
53 #define LP8727_STAT_EOC		0x30
54 
55 /* STATUS2 register */
56 #define LP8727_TEMP_STAT	(3 << 5)
57 #define LP8727_TEMP_SHIFT	5
58 
59 /* CHGCTRL2 register */
60 #define LP8727_ICHG_SHIFT	4
61 
62 enum lp8727_dev_id {
63 	LP8727_ID_NONE,
64 	LP8727_ID_TA,
65 	LP8727_ID_DEDICATED_CHG,
66 	LP8727_ID_USB_CHG,
67 	LP8727_ID_USB_DS,
68 	LP8727_ID_MAX,
69 };
70 
71 enum lp8727_die_temp {
72 	LP8788_TEMP_75C,
73 	LP8788_TEMP_95C,
74 	LP8788_TEMP_115C,
75 	LP8788_TEMP_135C,
76 };
77 
78 struct lp8727_psy {
79 	struct power_supply *ac;
80 	struct power_supply *usb;
81 	struct power_supply *batt;
82 };
83 
84 struct lp8727_chg {
85 	struct device *dev;
86 	struct i2c_client *client;
87 	struct mutex xfer_lock;
88 	struct lp8727_psy *psy;
89 	struct lp8727_platform_data *pdata;
90 
91 	/* Charger Data */
92 	enum lp8727_dev_id devid;
93 	struct lp8727_chg_param *chg_param;
94 
95 	/* Interrupt Handling */
96 	int irq;
97 	struct delayed_work work;
98 	unsigned long debounce_jiffies;
99 };
100 
101 static int lp8727_read_bytes(struct lp8727_chg *pchg, u8 reg, u8 *data, u8 len)
102 {
103 	s32 ret;
104 
105 	mutex_lock(&pchg->xfer_lock);
106 	ret = i2c_smbus_read_i2c_block_data(pchg->client, reg, len, data);
107 	mutex_unlock(&pchg->xfer_lock);
108 
109 	return (ret != len) ? -EIO : 0;
110 }
111 
112 static inline int lp8727_read_byte(struct lp8727_chg *pchg, u8 reg, u8 *data)
113 {
114 	return lp8727_read_bytes(pchg, reg, data, 1);
115 }
116 
117 static int lp8727_write_byte(struct lp8727_chg *pchg, u8 reg, u8 data)
118 {
119 	int ret;
120 
121 	mutex_lock(&pchg->xfer_lock);
122 	ret = i2c_smbus_write_byte_data(pchg->client, reg, data);
123 	mutex_unlock(&pchg->xfer_lock);
124 
125 	return ret;
126 }
127 
128 static bool lp8727_is_charger_attached(const char *name, int id)
129 {
130 	if (!strcmp(name, "ac"))
131 		return id == LP8727_ID_TA || id == LP8727_ID_DEDICATED_CHG;
132 	else if (!strcmp(name, "usb"))
133 		return id == LP8727_ID_USB_CHG;
134 
135 	return id >= LP8727_ID_TA && id <= LP8727_ID_USB_CHG;
136 }
137 
138 static int lp8727_init_device(struct lp8727_chg *pchg)
139 {
140 	u8 val;
141 	int ret;
142 	u8 intstat[LP8788_NUM_INTREGS];
143 
144 	/* clear interrupts */
145 	ret = lp8727_read_bytes(pchg, LP8727_INT1, intstat, LP8788_NUM_INTREGS);
146 	if (ret)
147 		return ret;
148 
149 	val = LP8727_ID200_EN | LP8727_ADC_EN | LP8727_CP_EN;
150 	ret = lp8727_write_byte(pchg, LP8727_CTRL1, val);
151 	if (ret)
152 		return ret;
153 
154 	val = LP8727_INT_EN | LP8727_CHGDET_EN;
155 	return lp8727_write_byte(pchg, LP8727_CTRL2, val);
156 }
157 
158 static int lp8727_is_dedicated_charger(struct lp8727_chg *pchg)
159 {
160 	u8 val;
161 
162 	lp8727_read_byte(pchg, LP8727_STATUS1, &val);
163 	return val & LP8727_DCPORT;
164 }
165 
166 static int lp8727_is_usb_charger(struct lp8727_chg *pchg)
167 {
168 	u8 val;
169 
170 	lp8727_read_byte(pchg, LP8727_STATUS1, &val);
171 	return val & LP8727_CHPORT;
172 }
173 
174 static inline void lp8727_ctrl_switch(struct lp8727_chg *pchg, u8 sw)
175 {
176 	lp8727_write_byte(pchg, LP8727_SWCTRL, sw);
177 }
178 
179 static void lp8727_id_detection(struct lp8727_chg *pchg, u8 id, int vbusin)
180 {
181 	struct lp8727_platform_data *pdata = pchg->pdata;
182 	u8 devid = LP8727_ID_NONE;
183 	u8 swctrl = LP8727_SW_DM1_HiZ | LP8727_SW_DP2_HiZ;
184 
185 	switch (id) {
186 	case 0x5:
187 		devid = LP8727_ID_TA;
188 		pchg->chg_param = pdata ? pdata->ac : NULL;
189 		break;
190 	case 0xB:
191 		if (lp8727_is_dedicated_charger(pchg)) {
192 			pchg->chg_param = pdata ? pdata->ac : NULL;
193 			devid = LP8727_ID_DEDICATED_CHG;
194 		} else if (lp8727_is_usb_charger(pchg)) {
195 			pchg->chg_param = pdata ? pdata->usb : NULL;
196 			devid = LP8727_ID_USB_CHG;
197 			swctrl = LP8727_SW_DM1_DM | LP8727_SW_DP2_DP;
198 		} else if (vbusin) {
199 			devid = LP8727_ID_USB_DS;
200 			swctrl = LP8727_SW_DM1_DM | LP8727_SW_DP2_DP;
201 		}
202 		break;
203 	default:
204 		devid = LP8727_ID_NONE;
205 		pchg->chg_param = NULL;
206 		break;
207 	}
208 
209 	pchg->devid = devid;
210 	lp8727_ctrl_switch(pchg, swctrl);
211 }
212 
213 static void lp8727_enable_chgdet(struct lp8727_chg *pchg)
214 {
215 	u8 val;
216 
217 	lp8727_read_byte(pchg, LP8727_CTRL2, &val);
218 	val |= LP8727_CHGDET_EN;
219 	lp8727_write_byte(pchg, LP8727_CTRL2, val);
220 }
221 
222 static void lp8727_delayed_func(struct work_struct *_work)
223 {
224 	struct lp8727_chg *pchg = container_of(_work, struct lp8727_chg,
225 						work.work);
226 	u8 intstat[LP8788_NUM_INTREGS];
227 	u8 idno;
228 	u8 vbus;
229 
230 	if (lp8727_read_bytes(pchg, LP8727_INT1, intstat, LP8788_NUM_INTREGS)) {
231 		dev_err(pchg->dev, "can not read INT registers\n");
232 		return;
233 	}
234 
235 	idno = intstat[0] & LP8727_IDNO;
236 	vbus = intstat[0] & LP8727_VBUS;
237 
238 	lp8727_id_detection(pchg, idno, vbus);
239 	lp8727_enable_chgdet(pchg);
240 
241 	power_supply_changed(pchg->psy->ac);
242 	power_supply_changed(pchg->psy->usb);
243 	power_supply_changed(pchg->psy->batt);
244 }
245 
246 static irqreturn_t lp8727_isr_func(int irq, void *ptr)
247 {
248 	struct lp8727_chg *pchg = ptr;
249 
250 	schedule_delayed_work(&pchg->work, pchg->debounce_jiffies);
251 	return IRQ_HANDLED;
252 }
253 
254 static int lp8727_setup_irq(struct lp8727_chg *pchg)
255 {
256 	int ret;
257 	int irq = pchg->client->irq;
258 	unsigned delay_msec = pchg->pdata ? pchg->pdata->debounce_msec :
259 						DEFAULT_DEBOUNCE_MSEC;
260 
261 	INIT_DELAYED_WORK(&pchg->work, lp8727_delayed_func);
262 
263 	if (irq <= 0) {
264 		dev_warn(pchg->dev, "invalid irq number: %d\n", irq);
265 		return 0;
266 	}
267 
268 	ret = request_threaded_irq(irq,	NULL, lp8727_isr_func,
269 				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
270 				"lp8727_irq", pchg);
271 
272 	if (ret)
273 		return ret;
274 
275 	pchg->irq = irq;
276 	pchg->debounce_jiffies = msecs_to_jiffies(delay_msec);
277 
278 	return 0;
279 }
280 
281 static void lp8727_release_irq(struct lp8727_chg *pchg)
282 {
283 	cancel_delayed_work_sync(&pchg->work);
284 
285 	if (pchg->irq)
286 		free_irq(pchg->irq, pchg);
287 }
288 
289 static enum power_supply_property lp8727_charger_prop[] = {
290 	POWER_SUPPLY_PROP_ONLINE,
291 };
292 
293 static enum power_supply_property lp8727_battery_prop[] = {
294 	POWER_SUPPLY_PROP_STATUS,
295 	POWER_SUPPLY_PROP_HEALTH,
296 	POWER_SUPPLY_PROP_PRESENT,
297 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
298 	POWER_SUPPLY_PROP_CAPACITY,
299 	POWER_SUPPLY_PROP_TEMP,
300 };
301 
302 static char *battery_supplied_to[] = {
303 	"main_batt",
304 };
305 
306 static int lp8727_charger_get_property(struct power_supply *psy,
307 				       enum power_supply_property psp,
308 				       union power_supply_propval *val)
309 {
310 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
311 
312 	if (psp != POWER_SUPPLY_PROP_ONLINE)
313 		return -EINVAL;
314 
315 	val->intval = lp8727_is_charger_attached(psy->desc->name, pchg->devid);
316 
317 	return 0;
318 }
319 
320 static bool lp8727_is_high_temperature(enum lp8727_die_temp temp)
321 {
322 	switch (temp) {
323 	case LP8788_TEMP_95C:
324 	case LP8788_TEMP_115C:
325 	case LP8788_TEMP_135C:
326 		return true;
327 	default:
328 		return false;
329 	}
330 }
331 
332 static int lp8727_battery_get_property(struct power_supply *psy,
333 				       enum power_supply_property psp,
334 				       union power_supply_propval *val)
335 {
336 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
337 	struct lp8727_platform_data *pdata = pchg->pdata;
338 	enum lp8727_die_temp temp;
339 	u8 read;
340 
341 	switch (psp) {
342 	case POWER_SUPPLY_PROP_STATUS:
343 		if (!lp8727_is_charger_attached(psy->desc->name, pchg->devid)) {
344 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
345 			return 0;
346 		}
347 
348 		lp8727_read_byte(pchg, LP8727_STATUS1, &read);
349 
350 		val->intval = (read & LP8727_CHGSTAT) == LP8727_STAT_EOC ?
351 				POWER_SUPPLY_STATUS_FULL :
352 				POWER_SUPPLY_STATUS_CHARGING;
353 		break;
354 	case POWER_SUPPLY_PROP_HEALTH:
355 		lp8727_read_byte(pchg, LP8727_STATUS2, &read);
356 		temp = (read & LP8727_TEMP_STAT) >> LP8727_TEMP_SHIFT;
357 
358 		val->intval = lp8727_is_high_temperature(temp) ?
359 			POWER_SUPPLY_HEALTH_OVERHEAT :
360 			POWER_SUPPLY_HEALTH_GOOD;
361 		break;
362 	case POWER_SUPPLY_PROP_PRESENT:
363 		if (!pdata)
364 			return -EINVAL;
365 
366 		if (pdata->get_batt_present)
367 			val->intval = pdata->get_batt_present();
368 		break;
369 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
370 		if (!pdata)
371 			return -EINVAL;
372 
373 		if (pdata->get_batt_level)
374 			val->intval = pdata->get_batt_level();
375 		break;
376 	case POWER_SUPPLY_PROP_CAPACITY:
377 		if (!pdata)
378 			return -EINVAL;
379 
380 		if (pdata->get_batt_capacity)
381 			val->intval = pdata->get_batt_capacity();
382 		break;
383 	case POWER_SUPPLY_PROP_TEMP:
384 		if (!pdata)
385 			return -EINVAL;
386 
387 		if (pdata->get_batt_temp)
388 			val->intval = pdata->get_batt_temp();
389 		break;
390 	default:
391 		break;
392 	}
393 
394 	return 0;
395 }
396 
397 static void lp8727_charger_changed(struct power_supply *psy)
398 {
399 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
400 	u8 eoc_level;
401 	u8 ichg;
402 	u8 val;
403 
404 	/* skip if no charger exists */
405 	if (!lp8727_is_charger_attached(psy->desc->name, pchg->devid))
406 		return;
407 
408 	/* update charging parameters */
409 	if (pchg->chg_param) {
410 		eoc_level = pchg->chg_param->eoc_level;
411 		ichg = pchg->chg_param->ichg;
412 		val = (ichg << LP8727_ICHG_SHIFT) | eoc_level;
413 		lp8727_write_byte(pchg, LP8727_CHGCTRL2, val);
414 	}
415 }
416 
417 static const struct power_supply_desc lp8727_ac_desc = {
418 	.name			= "ac",
419 	.type			= POWER_SUPPLY_TYPE_MAINS,
420 	.properties		= lp8727_charger_prop,
421 	.num_properties		= ARRAY_SIZE(lp8727_charger_prop),
422 	.get_property		= lp8727_charger_get_property,
423 };
424 
425 static const struct power_supply_desc lp8727_usb_desc = {
426 	.name			= "usb",
427 	.type			= POWER_SUPPLY_TYPE_USB,
428 	.properties		= lp8727_charger_prop,
429 	.num_properties		= ARRAY_SIZE(lp8727_charger_prop),
430 	.get_property		= lp8727_charger_get_property,
431 };
432 
433 static const struct power_supply_desc lp8727_batt_desc = {
434 	.name			= "main_batt",
435 	.type			= POWER_SUPPLY_TYPE_BATTERY,
436 	.properties		= lp8727_battery_prop,
437 	.num_properties		= ARRAY_SIZE(lp8727_battery_prop),
438 	.get_property		= lp8727_battery_get_property,
439 	.external_power_changed	= lp8727_charger_changed,
440 };
441 
442 static int lp8727_register_psy(struct lp8727_chg *pchg)
443 {
444 	struct power_supply_config psy_cfg = {}; /* Only for ac and usb */
445 	struct lp8727_psy *psy;
446 
447 	psy = devm_kzalloc(pchg->dev, sizeof(*psy), GFP_KERNEL);
448 	if (!psy)
449 		return -ENOMEM;
450 
451 	pchg->psy = psy;
452 
453 	psy_cfg.supplied_to = battery_supplied_to;
454 	psy_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
455 
456 	psy->ac = power_supply_register(pchg->dev, &lp8727_ac_desc, &psy_cfg);
457 	if (IS_ERR(psy->ac))
458 		goto err_psy_ac;
459 
460 	psy->usb = power_supply_register(pchg->dev, &lp8727_usb_desc,
461 					 &psy_cfg);
462 	if (IS_ERR(psy->usb))
463 		goto err_psy_usb;
464 
465 	psy->batt = power_supply_register(pchg->dev, &lp8727_batt_desc, NULL);
466 	if (IS_ERR(psy->batt))
467 		goto err_psy_batt;
468 
469 	return 0;
470 
471 err_psy_batt:
472 	power_supply_unregister(psy->usb);
473 err_psy_usb:
474 	power_supply_unregister(psy->ac);
475 err_psy_ac:
476 	return -EPERM;
477 }
478 
479 static void lp8727_unregister_psy(struct lp8727_chg *pchg)
480 {
481 	struct lp8727_psy *psy = pchg->psy;
482 
483 	if (!psy)
484 		return;
485 
486 	power_supply_unregister(psy->ac);
487 	power_supply_unregister(psy->usb);
488 	power_supply_unregister(psy->batt);
489 }
490 
491 #ifdef CONFIG_OF
492 static struct lp8727_chg_param
493 *lp8727_parse_charge_pdata(struct device *dev, struct device_node *np)
494 {
495 	struct lp8727_chg_param *param;
496 
497 	param = devm_kzalloc(dev, sizeof(*param), GFP_KERNEL);
498 	if (!param)
499 		goto out;
500 
501 	of_property_read_u8(np, "eoc-level", (u8 *)&param->eoc_level);
502 	of_property_read_u8(np, "charging-current", (u8 *)&param->ichg);
503 out:
504 	return param;
505 }
506 
507 static struct lp8727_platform_data *lp8727_parse_dt(struct device *dev)
508 {
509 	struct device_node *np = dev->of_node;
510 	struct device_node *child;
511 	struct lp8727_platform_data *pdata;
512 	const char *type;
513 
514 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
515 	if (!pdata)
516 		return ERR_PTR(-ENOMEM);
517 
518 	of_property_read_u32(np, "debounce-ms", &pdata->debounce_msec);
519 
520 	/* If charging parameter is not defined, just skip parsing the dt */
521 	if (of_get_child_count(np) == 0)
522 		return pdata;
523 
524 	for_each_child_of_node(np, child) {
525 		of_property_read_string(child, "charger-type", &type);
526 
527 		if (!strcmp(type, "ac"))
528 			pdata->ac = lp8727_parse_charge_pdata(dev, child);
529 
530 		if (!strcmp(type, "usb"))
531 			pdata->usb = lp8727_parse_charge_pdata(dev, child);
532 	}
533 
534 	return pdata;
535 }
536 #else
537 static struct lp8727_platform_data *lp8727_parse_dt(struct device *dev)
538 {
539 	return NULL;
540 }
541 #endif
542 
543 static int lp8727_probe(struct i2c_client *cl)
544 {
545 	struct lp8727_chg *pchg;
546 	struct lp8727_platform_data *pdata;
547 	int ret;
548 
549 	if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
550 		return -EIO;
551 
552 	if (cl->dev.of_node) {
553 		pdata = lp8727_parse_dt(&cl->dev);
554 		if (IS_ERR(pdata))
555 			return PTR_ERR(pdata);
556 	} else {
557 		pdata = dev_get_platdata(&cl->dev);
558 	}
559 
560 	pchg = devm_kzalloc(&cl->dev, sizeof(*pchg), GFP_KERNEL);
561 	if (!pchg)
562 		return -ENOMEM;
563 
564 	pchg->client = cl;
565 	pchg->dev = &cl->dev;
566 	pchg->pdata = pdata;
567 	i2c_set_clientdata(cl, pchg);
568 
569 	mutex_init(&pchg->xfer_lock);
570 
571 	ret = lp8727_init_device(pchg);
572 	if (ret) {
573 		dev_err(pchg->dev, "i2c communication err: %d", ret);
574 		return ret;
575 	}
576 
577 	ret = lp8727_register_psy(pchg);
578 	if (ret) {
579 		dev_err(pchg->dev, "power supplies register err: %d", ret);
580 		return ret;
581 	}
582 
583 	ret = lp8727_setup_irq(pchg);
584 	if (ret) {
585 		dev_err(pchg->dev, "irq handler err: %d", ret);
586 		lp8727_unregister_psy(pchg);
587 		return ret;
588 	}
589 
590 	return 0;
591 }
592 
593 static void lp8727_remove(struct i2c_client *cl)
594 {
595 	struct lp8727_chg *pchg = i2c_get_clientdata(cl);
596 
597 	lp8727_release_irq(pchg);
598 	lp8727_unregister_psy(pchg);
599 }
600 
601 static const struct of_device_id lp8727_dt_ids[] __maybe_unused = {
602 	{ .compatible = "ti,lp8727", },
603 	{ }
604 };
605 MODULE_DEVICE_TABLE(of, lp8727_dt_ids);
606 
607 static const struct i2c_device_id lp8727_ids[] = {
608 	{"lp8727", 0},
609 	{ }
610 };
611 MODULE_DEVICE_TABLE(i2c, lp8727_ids);
612 
613 static struct i2c_driver lp8727_driver = {
614 	.driver = {
615 		   .name = "lp8727",
616 		   .of_match_table = of_match_ptr(lp8727_dt_ids),
617 		   },
618 	.probe_new = lp8727_probe,
619 	.remove = lp8727_remove,
620 	.id_table = lp8727_ids,
621 };
622 module_i2c_driver(lp8727_driver);
623 
624 MODULE_DESCRIPTION("TI/National Semiconductor LP8727 charger driver");
625 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>, Daniel Jeong <daniel.jeong@ti.com>");
626 MODULE_LICENSE("GPL");
627