1 /*
2  * Driver for LP8727 Micro/Mini USB IC with integrated charger
3  *
4  *			Copyright (C) 2011 Texas Instruments
5  *			Copyright (C) 2011 National Semiconductor
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  */
12 
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/interrupt.h>
16 #include <linux/i2c.h>
17 #include <linux/power_supply.h>
18 #include <linux/platform_data/lp8727.h>
19 #include <linux/of.h>
20 
21 #define LP8788_NUM_INTREGS	2
22 #define DEFAULT_DEBOUNCE_MSEC	270
23 
24 /* Registers */
25 #define LP8727_CTRL1		0x1
26 #define LP8727_CTRL2		0x2
27 #define LP8727_SWCTRL		0x3
28 #define LP8727_INT1		0x4
29 #define LP8727_INT2		0x5
30 #define LP8727_STATUS1		0x6
31 #define LP8727_STATUS2		0x7
32 #define LP8727_CHGCTRL2		0x9
33 
34 /* CTRL1 register */
35 #define LP8727_CP_EN		BIT(0)
36 #define LP8727_ADC_EN		BIT(1)
37 #define LP8727_ID200_EN		BIT(4)
38 
39 /* CTRL2 register */
40 #define LP8727_CHGDET_EN	BIT(1)
41 #define LP8727_INT_EN		BIT(6)
42 
43 /* SWCTRL register */
44 #define LP8727_SW_DM1_DM	(0x0 << 0)
45 #define LP8727_SW_DM1_HiZ	(0x7 << 0)
46 #define LP8727_SW_DP2_DP	(0x0 << 3)
47 #define LP8727_SW_DP2_HiZ	(0x7 << 3)
48 
49 /* INT1 register */
50 #define LP8727_IDNO		(0xF << 0)
51 #define LP8727_VBUS		BIT(4)
52 
53 /* STATUS1 register */
54 #define LP8727_CHGSTAT		(3 << 4)
55 #define LP8727_CHPORT		BIT(6)
56 #define LP8727_DCPORT		BIT(7)
57 #define LP8727_STAT_EOC		0x30
58 
59 /* STATUS2 register */
60 #define LP8727_TEMP_STAT	(3 << 5)
61 #define LP8727_TEMP_SHIFT	5
62 
63 /* CHGCTRL2 register */
64 #define LP8727_ICHG_SHIFT	4
65 
66 enum lp8727_dev_id {
67 	LP8727_ID_NONE,
68 	LP8727_ID_TA,
69 	LP8727_ID_DEDICATED_CHG,
70 	LP8727_ID_USB_CHG,
71 	LP8727_ID_USB_DS,
72 	LP8727_ID_MAX,
73 };
74 
75 enum lp8727_die_temp {
76 	LP8788_TEMP_75C,
77 	LP8788_TEMP_95C,
78 	LP8788_TEMP_115C,
79 	LP8788_TEMP_135C,
80 };
81 
82 struct lp8727_psy {
83 	struct power_supply *ac;
84 	struct power_supply *usb;
85 	struct power_supply *batt;
86 };
87 
88 struct lp8727_chg {
89 	struct device *dev;
90 	struct i2c_client *client;
91 	struct mutex xfer_lock;
92 	struct lp8727_psy *psy;
93 	struct lp8727_platform_data *pdata;
94 
95 	/* Charger Data */
96 	enum lp8727_dev_id devid;
97 	struct lp8727_chg_param *chg_param;
98 
99 	/* Interrupt Handling */
100 	int irq;
101 	struct delayed_work work;
102 	unsigned long debounce_jiffies;
103 };
104 
105 static int lp8727_read_bytes(struct lp8727_chg *pchg, u8 reg, u8 *data, u8 len)
106 {
107 	s32 ret;
108 
109 	mutex_lock(&pchg->xfer_lock);
110 	ret = i2c_smbus_read_i2c_block_data(pchg->client, reg, len, data);
111 	mutex_unlock(&pchg->xfer_lock);
112 
113 	return (ret != len) ? -EIO : 0;
114 }
115 
116 static inline int lp8727_read_byte(struct lp8727_chg *pchg, u8 reg, u8 *data)
117 {
118 	return lp8727_read_bytes(pchg, reg, data, 1);
119 }
120 
121 static int lp8727_write_byte(struct lp8727_chg *pchg, u8 reg, u8 data)
122 {
123 	int ret;
124 
125 	mutex_lock(&pchg->xfer_lock);
126 	ret = i2c_smbus_write_byte_data(pchg->client, reg, data);
127 	mutex_unlock(&pchg->xfer_lock);
128 
129 	return ret;
130 }
131 
132 static bool lp8727_is_charger_attached(const char *name, int id)
133 {
134 	if (!strcmp(name, "ac"))
135 		return id == LP8727_ID_TA || id == LP8727_ID_DEDICATED_CHG;
136 	else if (!strcmp(name, "usb"))
137 		return id == LP8727_ID_USB_CHG;
138 
139 	return id >= LP8727_ID_TA && id <= LP8727_ID_USB_CHG;
140 }
141 
142 static int lp8727_init_device(struct lp8727_chg *pchg)
143 {
144 	u8 val;
145 	int ret;
146 	u8 intstat[LP8788_NUM_INTREGS];
147 
148 	/* clear interrupts */
149 	ret = lp8727_read_bytes(pchg, LP8727_INT1, intstat, LP8788_NUM_INTREGS);
150 	if (ret)
151 		return ret;
152 
153 	val = LP8727_ID200_EN | LP8727_ADC_EN | LP8727_CP_EN;
154 	ret = lp8727_write_byte(pchg, LP8727_CTRL1, val);
155 	if (ret)
156 		return ret;
157 
158 	val = LP8727_INT_EN | LP8727_CHGDET_EN;
159 	return lp8727_write_byte(pchg, LP8727_CTRL2, val);
160 }
161 
162 static int lp8727_is_dedicated_charger(struct lp8727_chg *pchg)
163 {
164 	u8 val;
165 
166 	lp8727_read_byte(pchg, LP8727_STATUS1, &val);
167 	return val & LP8727_DCPORT;
168 }
169 
170 static int lp8727_is_usb_charger(struct lp8727_chg *pchg)
171 {
172 	u8 val;
173 
174 	lp8727_read_byte(pchg, LP8727_STATUS1, &val);
175 	return val & LP8727_CHPORT;
176 }
177 
178 static inline void lp8727_ctrl_switch(struct lp8727_chg *pchg, u8 sw)
179 {
180 	lp8727_write_byte(pchg, LP8727_SWCTRL, sw);
181 }
182 
183 static void lp8727_id_detection(struct lp8727_chg *pchg, u8 id, int vbusin)
184 {
185 	struct lp8727_platform_data *pdata = pchg->pdata;
186 	u8 devid = LP8727_ID_NONE;
187 	u8 swctrl = LP8727_SW_DM1_HiZ | LP8727_SW_DP2_HiZ;
188 
189 	switch (id) {
190 	case 0x5:
191 		devid = LP8727_ID_TA;
192 		pchg->chg_param = pdata ? pdata->ac : NULL;
193 		break;
194 	case 0xB:
195 		if (lp8727_is_dedicated_charger(pchg)) {
196 			pchg->chg_param = pdata ? pdata->ac : NULL;
197 			devid = LP8727_ID_DEDICATED_CHG;
198 		} else if (lp8727_is_usb_charger(pchg)) {
199 			pchg->chg_param = pdata ? pdata->usb : NULL;
200 			devid = LP8727_ID_USB_CHG;
201 			swctrl = LP8727_SW_DM1_DM | LP8727_SW_DP2_DP;
202 		} else if (vbusin) {
203 			devid = LP8727_ID_USB_DS;
204 			swctrl = LP8727_SW_DM1_DM | LP8727_SW_DP2_DP;
205 		}
206 		break;
207 	default:
208 		devid = LP8727_ID_NONE;
209 		pchg->chg_param = NULL;
210 		break;
211 	}
212 
213 	pchg->devid = devid;
214 	lp8727_ctrl_switch(pchg, swctrl);
215 }
216 
217 static void lp8727_enable_chgdet(struct lp8727_chg *pchg)
218 {
219 	u8 val;
220 
221 	lp8727_read_byte(pchg, LP8727_CTRL2, &val);
222 	val |= LP8727_CHGDET_EN;
223 	lp8727_write_byte(pchg, LP8727_CTRL2, val);
224 }
225 
226 static void lp8727_delayed_func(struct work_struct *_work)
227 {
228 	struct lp8727_chg *pchg = container_of(_work, struct lp8727_chg,
229 						work.work);
230 	u8 intstat[LP8788_NUM_INTREGS];
231 	u8 idno;
232 	u8 vbus;
233 
234 	if (lp8727_read_bytes(pchg, LP8727_INT1, intstat, LP8788_NUM_INTREGS)) {
235 		dev_err(pchg->dev, "can not read INT registers\n");
236 		return;
237 	}
238 
239 	idno = intstat[0] & LP8727_IDNO;
240 	vbus = intstat[0] & LP8727_VBUS;
241 
242 	lp8727_id_detection(pchg, idno, vbus);
243 	lp8727_enable_chgdet(pchg);
244 
245 	power_supply_changed(pchg->psy->ac);
246 	power_supply_changed(pchg->psy->usb);
247 	power_supply_changed(pchg->psy->batt);
248 }
249 
250 static irqreturn_t lp8727_isr_func(int irq, void *ptr)
251 {
252 	struct lp8727_chg *pchg = ptr;
253 
254 	schedule_delayed_work(&pchg->work, pchg->debounce_jiffies);
255 	return IRQ_HANDLED;
256 }
257 
258 static int lp8727_setup_irq(struct lp8727_chg *pchg)
259 {
260 	int ret;
261 	int irq = pchg->client->irq;
262 	unsigned delay_msec = pchg->pdata ? pchg->pdata->debounce_msec :
263 						DEFAULT_DEBOUNCE_MSEC;
264 
265 	INIT_DELAYED_WORK(&pchg->work, lp8727_delayed_func);
266 
267 	if (irq <= 0) {
268 		dev_warn(pchg->dev, "invalid irq number: %d\n", irq);
269 		return 0;
270 	}
271 
272 	ret = request_threaded_irq(irq,	NULL, lp8727_isr_func,
273 				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
274 				"lp8727_irq", pchg);
275 
276 	if (ret)
277 		return ret;
278 
279 	pchg->irq = irq;
280 	pchg->debounce_jiffies = msecs_to_jiffies(delay_msec);
281 
282 	return 0;
283 }
284 
285 static void lp8727_release_irq(struct lp8727_chg *pchg)
286 {
287 	cancel_delayed_work_sync(&pchg->work);
288 
289 	if (pchg->irq)
290 		free_irq(pchg->irq, pchg);
291 }
292 
293 static enum power_supply_property lp8727_charger_prop[] = {
294 	POWER_SUPPLY_PROP_ONLINE,
295 };
296 
297 static enum power_supply_property lp8727_battery_prop[] = {
298 	POWER_SUPPLY_PROP_STATUS,
299 	POWER_SUPPLY_PROP_HEALTH,
300 	POWER_SUPPLY_PROP_PRESENT,
301 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
302 	POWER_SUPPLY_PROP_CAPACITY,
303 	POWER_SUPPLY_PROP_TEMP,
304 };
305 
306 static char *battery_supplied_to[] = {
307 	"main_batt",
308 };
309 
310 static int lp8727_charger_get_property(struct power_supply *psy,
311 				       enum power_supply_property psp,
312 				       union power_supply_propval *val)
313 {
314 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
315 
316 	if (psp != POWER_SUPPLY_PROP_ONLINE)
317 		return -EINVAL;
318 
319 	val->intval = lp8727_is_charger_attached(psy->desc->name, pchg->devid);
320 
321 	return 0;
322 }
323 
324 static bool lp8727_is_high_temperature(enum lp8727_die_temp temp)
325 {
326 	switch (temp) {
327 	case LP8788_TEMP_95C:
328 	case LP8788_TEMP_115C:
329 	case LP8788_TEMP_135C:
330 		return true;
331 	default:
332 		return false;
333 	}
334 }
335 
336 static int lp8727_battery_get_property(struct power_supply *psy,
337 				       enum power_supply_property psp,
338 				       union power_supply_propval *val)
339 {
340 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
341 	struct lp8727_platform_data *pdata = pchg->pdata;
342 	enum lp8727_die_temp temp;
343 	u8 read;
344 
345 	switch (psp) {
346 	case POWER_SUPPLY_PROP_STATUS:
347 		if (!lp8727_is_charger_attached(psy->desc->name, pchg->devid)) {
348 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
349 			return 0;
350 		}
351 
352 		lp8727_read_byte(pchg, LP8727_STATUS1, &read);
353 
354 		val->intval = (read & LP8727_CHGSTAT) == LP8727_STAT_EOC ?
355 				POWER_SUPPLY_STATUS_FULL :
356 				POWER_SUPPLY_STATUS_CHARGING;
357 		break;
358 	case POWER_SUPPLY_PROP_HEALTH:
359 		lp8727_read_byte(pchg, LP8727_STATUS2, &read);
360 		temp = (read & LP8727_TEMP_STAT) >> LP8727_TEMP_SHIFT;
361 
362 		val->intval = lp8727_is_high_temperature(temp) ?
363 			POWER_SUPPLY_HEALTH_OVERHEAT :
364 			POWER_SUPPLY_HEALTH_GOOD;
365 		break;
366 	case POWER_SUPPLY_PROP_PRESENT:
367 		if (!pdata)
368 			return -EINVAL;
369 
370 		if (pdata->get_batt_present)
371 			val->intval = pdata->get_batt_present();
372 		break;
373 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
374 		if (!pdata)
375 			return -EINVAL;
376 
377 		if (pdata->get_batt_level)
378 			val->intval = pdata->get_batt_level();
379 		break;
380 	case POWER_SUPPLY_PROP_CAPACITY:
381 		if (!pdata)
382 			return -EINVAL;
383 
384 		if (pdata->get_batt_capacity)
385 			val->intval = pdata->get_batt_capacity();
386 		break;
387 	case POWER_SUPPLY_PROP_TEMP:
388 		if (!pdata)
389 			return -EINVAL;
390 
391 		if (pdata->get_batt_temp)
392 			val->intval = pdata->get_batt_temp();
393 		break;
394 	default:
395 		break;
396 	}
397 
398 	return 0;
399 }
400 
401 static void lp8727_charger_changed(struct power_supply *psy)
402 {
403 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev.parent);
404 	u8 eoc_level;
405 	u8 ichg;
406 	u8 val;
407 
408 	/* skip if no charger exists */
409 	if (!lp8727_is_charger_attached(psy->desc->name, pchg->devid))
410 		return;
411 
412 	/* update charging parameters */
413 	if (pchg->chg_param) {
414 		eoc_level = pchg->chg_param->eoc_level;
415 		ichg = pchg->chg_param->ichg;
416 		val = (ichg << LP8727_ICHG_SHIFT) | eoc_level;
417 		lp8727_write_byte(pchg, LP8727_CHGCTRL2, val);
418 	}
419 }
420 
421 static const struct power_supply_desc lp8727_ac_desc = {
422 	.name			= "ac",
423 	.type			= POWER_SUPPLY_TYPE_MAINS,
424 	.properties		= lp8727_charger_prop,
425 	.num_properties		= ARRAY_SIZE(lp8727_charger_prop),
426 	.get_property		= lp8727_charger_get_property,
427 };
428 
429 static const struct power_supply_desc lp8727_usb_desc = {
430 	.name			= "usb",
431 	.type			= POWER_SUPPLY_TYPE_USB,
432 	.properties		= lp8727_charger_prop,
433 	.num_properties		= ARRAY_SIZE(lp8727_charger_prop),
434 	.get_property		= lp8727_charger_get_property,
435 };
436 
437 static const struct power_supply_desc lp8727_batt_desc = {
438 	.name			= "main_batt",
439 	.type			= POWER_SUPPLY_TYPE_BATTERY,
440 	.properties		= lp8727_battery_prop,
441 	.num_properties		= ARRAY_SIZE(lp8727_battery_prop),
442 	.get_property		= lp8727_battery_get_property,
443 	.external_power_changed	= lp8727_charger_changed,
444 };
445 
446 static int lp8727_register_psy(struct lp8727_chg *pchg)
447 {
448 	struct power_supply_config psy_cfg = {}; /* Only for ac and usb */
449 	struct lp8727_psy *psy;
450 
451 	psy = devm_kzalloc(pchg->dev, sizeof(*psy), GFP_KERNEL);
452 	if (!psy)
453 		return -ENOMEM;
454 
455 	pchg->psy = psy;
456 
457 	psy_cfg.supplied_to = battery_supplied_to;
458 	psy_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to);
459 
460 	psy->ac = power_supply_register(pchg->dev, &lp8727_ac_desc, &psy_cfg);
461 	if (IS_ERR(psy->ac))
462 		goto err_psy_ac;
463 
464 	psy->usb = power_supply_register(pchg->dev, &lp8727_usb_desc,
465 					 &psy_cfg);
466 	if (IS_ERR(psy->usb))
467 		goto err_psy_usb;
468 
469 	psy->batt = power_supply_register(pchg->dev, &lp8727_batt_desc, NULL);
470 	if (IS_ERR(psy->batt))
471 		goto err_psy_batt;
472 
473 	return 0;
474 
475 err_psy_batt:
476 	power_supply_unregister(psy->usb);
477 err_psy_usb:
478 	power_supply_unregister(psy->ac);
479 err_psy_ac:
480 	return -EPERM;
481 }
482 
483 static void lp8727_unregister_psy(struct lp8727_chg *pchg)
484 {
485 	struct lp8727_psy *psy = pchg->psy;
486 
487 	if (!psy)
488 		return;
489 
490 	power_supply_unregister(psy->ac);
491 	power_supply_unregister(psy->usb);
492 	power_supply_unregister(psy->batt);
493 }
494 
495 #ifdef CONFIG_OF
496 static struct lp8727_chg_param
497 *lp8727_parse_charge_pdata(struct device *dev, struct device_node *np)
498 {
499 	struct lp8727_chg_param *param;
500 
501 	param = devm_kzalloc(dev, sizeof(*param), GFP_KERNEL);
502 	if (!param)
503 		goto out;
504 
505 	of_property_read_u8(np, "eoc-level", (u8 *)&param->eoc_level);
506 	of_property_read_u8(np, "charging-current", (u8 *)&param->ichg);
507 out:
508 	return param;
509 }
510 
511 static struct lp8727_platform_data *lp8727_parse_dt(struct device *dev)
512 {
513 	struct device_node *np = dev->of_node;
514 	struct device_node *child;
515 	struct lp8727_platform_data *pdata;
516 	const char *type;
517 
518 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
519 	if (!pdata)
520 		return ERR_PTR(-ENOMEM);
521 
522 	of_property_read_u32(np, "debounce-ms", &pdata->debounce_msec);
523 
524 	/* If charging parameter is not defined, just skip parsing the dt */
525 	if (of_get_child_count(np) == 0)
526 		return pdata;
527 
528 	for_each_child_of_node(np, child) {
529 		of_property_read_string(child, "charger-type", &type);
530 
531 		if (!strcmp(type, "ac"))
532 			pdata->ac = lp8727_parse_charge_pdata(dev, child);
533 
534 		if (!strcmp(type, "usb"))
535 			pdata->usb = lp8727_parse_charge_pdata(dev, child);
536 	}
537 
538 	return pdata;
539 }
540 #else
541 static struct lp8727_platform_data *lp8727_parse_dt(struct device *dev)
542 {
543 	return NULL;
544 }
545 #endif
546 
547 static int lp8727_probe(struct i2c_client *cl, const struct i2c_device_id *id)
548 {
549 	struct lp8727_chg *pchg;
550 	struct lp8727_platform_data *pdata;
551 	int ret;
552 
553 	if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
554 		return -EIO;
555 
556 	if (cl->dev.of_node) {
557 		pdata = lp8727_parse_dt(&cl->dev);
558 		if (IS_ERR(pdata))
559 			return PTR_ERR(pdata);
560 	} else {
561 		pdata = dev_get_platdata(&cl->dev);
562 	}
563 
564 	pchg = devm_kzalloc(&cl->dev, sizeof(*pchg), GFP_KERNEL);
565 	if (!pchg)
566 		return -ENOMEM;
567 
568 	pchg->client = cl;
569 	pchg->dev = &cl->dev;
570 	pchg->pdata = pdata;
571 	i2c_set_clientdata(cl, pchg);
572 
573 	mutex_init(&pchg->xfer_lock);
574 
575 	ret = lp8727_init_device(pchg);
576 	if (ret) {
577 		dev_err(pchg->dev, "i2c communication err: %d", ret);
578 		return ret;
579 	}
580 
581 	ret = lp8727_register_psy(pchg);
582 	if (ret) {
583 		dev_err(pchg->dev, "power supplies register err: %d", ret);
584 		return ret;
585 	}
586 
587 	ret = lp8727_setup_irq(pchg);
588 	if (ret) {
589 		dev_err(pchg->dev, "irq handler err: %d", ret);
590 		lp8727_unregister_psy(pchg);
591 		return ret;
592 	}
593 
594 	return 0;
595 }
596 
597 static int lp8727_remove(struct i2c_client *cl)
598 {
599 	struct lp8727_chg *pchg = i2c_get_clientdata(cl);
600 
601 	lp8727_release_irq(pchg);
602 	lp8727_unregister_psy(pchg);
603 	return 0;
604 }
605 
606 static const struct of_device_id lp8727_dt_ids[] = {
607 	{ .compatible = "ti,lp8727", },
608 	{ }
609 };
610 MODULE_DEVICE_TABLE(of, lp8727_dt_ids);
611 
612 static const struct i2c_device_id lp8727_ids[] = {
613 	{"lp8727", 0},
614 	{ }
615 };
616 MODULE_DEVICE_TABLE(i2c, lp8727_ids);
617 
618 static struct i2c_driver lp8727_driver = {
619 	.driver = {
620 		   .name = "lp8727",
621 		   .of_match_table = of_match_ptr(lp8727_dt_ids),
622 		   },
623 	.probe = lp8727_probe,
624 	.remove = lp8727_remove,
625 	.id_table = lp8727_ids,
626 };
627 module_i2c_driver(lp8727_driver);
628 
629 MODULE_DESCRIPTION("TI/National Semiconductor LP8727 charger driver");
630 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>, Daniel Jeong <daniel.jeong@ti.com>");
631 MODULE_LICENSE("GPL");
632