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
66enum 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
75enum lp8727_die_temp {
76	LP8788_TEMP_75C,
77	LP8788_TEMP_95C,
78	LP8788_TEMP_115C,
79	LP8788_TEMP_135C,
80};
81
82struct lp8727_psy {
83	struct power_supply *ac;
84	struct power_supply *usb;
85	struct power_supply *batt;
86};
87
88struct 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
105static 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
116static 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
121static 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
132static 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
142static 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
162static 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
170static 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
178static inline void lp8727_ctrl_switch(struct lp8727_chg *pchg, u8 sw)
179{
180	lp8727_write_byte(pchg, LP8727_SWCTRL, sw);
181}
182
183static 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
217static 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
226static 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
250static 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
258static 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
285static 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
293static enum power_supply_property lp8727_charger_prop[] = {
294	POWER_SUPPLY_PROP_ONLINE,
295};
296
297static 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
306static char *battery_supplied_to[] = {
307	"main_batt",
308};
309
310static 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
324static 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
336static 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
401static 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
421static 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
429static 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
437static 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
446static 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
475err_psy_batt:
476	power_supply_unregister(psy->usb);
477err_psy_usb:
478	power_supply_unregister(psy->ac);
479err_psy_ac:
480	return -EPERM;
481}
482
483static 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
496static 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);
507out:
508	return param;
509}
510
511static int 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	/* If charging parameter is not defined, just skip parsing the dt */
519	if (of_get_child_count(np) == 0)
520		goto out;
521
522	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
523	if (!pdata)
524		return -ENOMEM;
525
526	of_property_read_u32(np, "debounce-ms", &pdata->debounce_msec);
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	dev->platform_data = pdata;
539out:
540	return 0;
541}
542#else
543static int lp8727_parse_dt(struct device *dev)
544{
545	return 0;
546}
547#endif
548
549static int lp8727_probe(struct i2c_client *cl, const struct i2c_device_id *id)
550{
551	struct lp8727_chg *pchg;
552	int ret;
553
554	if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
555		return -EIO;
556
557	if (cl->dev.of_node) {
558		ret = lp8727_parse_dt(&cl->dev);
559		if (ret)
560			return ret;
561	}
562
563	pchg = devm_kzalloc(&cl->dev, sizeof(*pchg), GFP_KERNEL);
564	if (!pchg)
565		return -ENOMEM;
566
567	pchg->client = cl;
568	pchg->dev = &cl->dev;
569	pchg->pdata = cl->dev.platform_data;
570	i2c_set_clientdata(cl, pchg);
571
572	mutex_init(&pchg->xfer_lock);
573
574	ret = lp8727_init_device(pchg);
575	if (ret) {
576		dev_err(pchg->dev, "i2c communication err: %d", ret);
577		return ret;
578	}
579
580	ret = lp8727_register_psy(pchg);
581	if (ret) {
582		dev_err(pchg->dev, "power supplies register err: %d", ret);
583		return ret;
584	}
585
586	ret = lp8727_setup_irq(pchg);
587	if (ret) {
588		dev_err(pchg->dev, "irq handler err: %d", ret);
589		lp8727_unregister_psy(pchg);
590		return ret;
591	}
592
593	return 0;
594}
595
596static int lp8727_remove(struct i2c_client *cl)
597{
598	struct lp8727_chg *pchg = i2c_get_clientdata(cl);
599
600	lp8727_release_irq(pchg);
601	lp8727_unregister_psy(pchg);
602	return 0;
603}
604
605static const struct of_device_id lp8727_dt_ids[] = {
606	{ .compatible = "ti,lp8727", },
607	{ }
608};
609MODULE_DEVICE_TABLE(of, lp8727_dt_ids);
610
611static const struct i2c_device_id lp8727_ids[] = {
612	{"lp8727", 0},
613	{ }
614};
615MODULE_DEVICE_TABLE(i2c, lp8727_ids);
616
617static struct i2c_driver lp8727_driver = {
618	.driver = {
619		   .name = "lp8727",
620		   .of_match_table = of_match_ptr(lp8727_dt_ids),
621		   },
622	.probe = lp8727_probe,
623	.remove = lp8727_remove,
624	.id_table = lp8727_ids,
625};
626module_i2c_driver(lp8727_driver);
627
628MODULE_DESCRIPTION("TI/National Semiconductor LP8727 charger driver");
629MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>, Daniel Jeong <daniel.jeong@ti.com>");
630MODULE_LICENSE("GPL");
631