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/lp8727.h>
19 
20 #define DEBOUNCE_MSEC	270
21 
22 /* Registers */
23 #define CTRL1		0x1
24 #define CTRL2		0x2
25 #define	SWCTRL		0x3
26 #define INT1		0x4
27 #define INT2		0x5
28 #define STATUS1		0x6
29 #define STATUS2		0x7
30 #define CHGCTRL2	0x9
31 
32 /* CTRL1 register */
33 #define CP_EN		(1 << 0)
34 #define ADC_EN		(1 << 1)
35 #define ID200_EN	(1 << 4)
36 
37 /* CTRL2 register */
38 #define CHGDET_EN	(1 << 1)
39 #define INT_EN		(1 << 6)
40 
41 /* SWCTRL register */
42 #define SW_DM1_DM	(0x0 << 0)
43 #define SW_DM1_U1	(0x1 << 0)
44 #define SW_DM1_HiZ	(0x7 << 0)
45 #define SW_DP2_DP	(0x0 << 3)
46 #define SW_DP2_U2	(0x1 << 3)
47 #define SW_DP2_HiZ	(0x7 << 3)
48 
49 /* INT1 register */
50 #define IDNO		(0xF << 0)
51 #define VBUS		(1 << 4)
52 
53 /* STATUS1 register */
54 #define CHGSTAT		(3 << 4)
55 #define CHPORT		(1 << 6)
56 #define DCPORT		(1 << 7)
57 
58 /* STATUS2 register */
59 #define TEMP_STAT	(3 << 5)
60 
61 enum lp8727_dev_id {
62 	ID_NONE,
63 	ID_TA,
64 	ID_DEDICATED_CHG,
65 	ID_USB_CHG,
66 	ID_USB_DS,
67 	ID_MAX,
68 };
69 
70 enum lp8727_chg_stat {
71 	PRECHG,
72 	CC,
73 	CV,
74 	EOC,
75 };
76 
77 struct lp8727_psy {
78 	struct power_supply ac;
79 	struct power_supply usb;
80 	struct power_supply batt;
81 };
82 
83 struct lp8727_chg {
84 	struct device *dev;
85 	struct i2c_client *client;
86 	struct mutex xfer_lock;
87 	struct delayed_work work;
88 	struct workqueue_struct *irqthread;
89 	struct lp8727_platform_data *pdata;
90 	struct lp8727_psy *psy;
91 	struct lp8727_chg_param *chg_parm;
92 	enum lp8727_dev_id devid;
93 };
94 
lp8727_read_bytes(struct lp8727_chg * pchg,u8 reg,u8 * data,u8 len)95 static int lp8727_read_bytes(struct lp8727_chg *pchg, u8 reg, u8 *data, u8 len)
96 {
97 	s32 ret;
98 
99 	mutex_lock(&pchg->xfer_lock);
100 	ret = i2c_smbus_read_i2c_block_data(pchg->client, reg, len, data);
101 	mutex_unlock(&pchg->xfer_lock);
102 
103 	return (ret != len) ? -EIO : 0;
104 }
105 
lp8727_read_byte(struct lp8727_chg * pchg,u8 reg,u8 * data)106 static inline int lp8727_read_byte(struct lp8727_chg *pchg, u8 reg, u8 *data)
107 {
108 	return lp8727_read_bytes(pchg, reg, data, 1);
109 }
110 
lp8727_write_byte(struct lp8727_chg * pchg,u8 reg,u8 data)111 static int lp8727_write_byte(struct lp8727_chg *pchg, u8 reg, u8 data)
112 {
113 	int ret;
114 
115 	mutex_lock(&pchg->xfer_lock);
116 	ret = i2c_smbus_write_byte_data(pchg->client, reg, data);
117 	mutex_unlock(&pchg->xfer_lock);
118 
119 	return ret;
120 }
121 
lp8727_is_charger_attached(const char * name,int id)122 static int lp8727_is_charger_attached(const char *name, int id)
123 {
124 	if (name) {
125 		if (!strcmp(name, "ac"))
126 			return (id == ID_TA || id == ID_DEDICATED_CHG) ? 1 : 0;
127 		else if (!strcmp(name, "usb"))
128 			return (id == ID_USB_CHG) ? 1 : 0;
129 	}
130 
131 	return (id >= ID_TA && id <= ID_USB_CHG) ? 1 : 0;
132 }
133 
lp8727_init_device(struct lp8727_chg * pchg)134 static int lp8727_init_device(struct lp8727_chg *pchg)
135 {
136 	u8 val;
137 	int ret;
138 
139 	val = ID200_EN | ADC_EN | CP_EN;
140 	ret = lp8727_write_byte(pchg, CTRL1, val);
141 	if (ret)
142 		return ret;
143 
144 	val = INT_EN | CHGDET_EN;
145 	ret = lp8727_write_byte(pchg, CTRL2, val);
146 	if (ret)
147 		return ret;
148 
149 	return 0;
150 }
151 
lp8727_is_dedicated_charger(struct lp8727_chg * pchg)152 static int lp8727_is_dedicated_charger(struct lp8727_chg *pchg)
153 {
154 	u8 val;
155 	lp8727_read_byte(pchg, STATUS1, &val);
156 	return val & DCPORT;
157 }
158 
lp8727_is_usb_charger(struct lp8727_chg * pchg)159 static int lp8727_is_usb_charger(struct lp8727_chg *pchg)
160 {
161 	u8 val;
162 	lp8727_read_byte(pchg, STATUS1, &val);
163 	return val & CHPORT;
164 }
165 
lp8727_ctrl_switch(struct lp8727_chg * pchg,u8 sw)166 static void lp8727_ctrl_switch(struct lp8727_chg *pchg, u8 sw)
167 {
168 	lp8727_write_byte(pchg, SWCTRL, sw);
169 }
170 
lp8727_id_detection(struct lp8727_chg * pchg,u8 id,int vbusin)171 static void lp8727_id_detection(struct lp8727_chg *pchg, u8 id, int vbusin)
172 {
173 	u8 devid = ID_NONE;
174 	u8 swctrl = SW_DM1_HiZ | SW_DP2_HiZ;
175 
176 	switch (id) {
177 	case 0x5:
178 		devid = ID_TA;
179 		pchg->chg_parm = &pchg->pdata->ac;
180 		break;
181 	case 0xB:
182 		if (lp8727_is_dedicated_charger(pchg)) {
183 			pchg->chg_parm = &pchg->pdata->ac;
184 			devid = ID_DEDICATED_CHG;
185 		} else if (lp8727_is_usb_charger(pchg)) {
186 			pchg->chg_parm = &pchg->pdata->usb;
187 			devid = ID_USB_CHG;
188 			swctrl = SW_DM1_DM | SW_DP2_DP;
189 		} else if (vbusin) {
190 			devid = ID_USB_DS;
191 			swctrl = SW_DM1_DM | SW_DP2_DP;
192 		}
193 		break;
194 	default:
195 		devid = ID_NONE;
196 		pchg->chg_parm = NULL;
197 		break;
198 	}
199 
200 	pchg->devid = devid;
201 	lp8727_ctrl_switch(pchg, swctrl);
202 }
203 
lp8727_enable_chgdet(struct lp8727_chg * pchg)204 static void lp8727_enable_chgdet(struct lp8727_chg *pchg)
205 {
206 	u8 val;
207 
208 	lp8727_read_byte(pchg, CTRL2, &val);
209 	val |= CHGDET_EN;
210 	lp8727_write_byte(pchg, CTRL2, val);
211 }
212 
lp8727_delayed_func(struct work_struct * _work)213 static void lp8727_delayed_func(struct work_struct *_work)
214 {
215 	u8 intstat[2], idno, vbus;
216 	struct lp8727_chg *pchg =
217 	    container_of(_work, struct lp8727_chg, work.work);
218 
219 	if (lp8727_read_bytes(pchg, INT1, intstat, 2)) {
220 		dev_err(pchg->dev, "can not read INT registers\n");
221 		return;
222 	}
223 
224 	idno = intstat[0] & IDNO;
225 	vbus = intstat[0] & VBUS;
226 
227 	lp8727_id_detection(pchg, idno, vbus);
228 	lp8727_enable_chgdet(pchg);
229 
230 	power_supply_changed(&pchg->psy->ac);
231 	power_supply_changed(&pchg->psy->usb);
232 	power_supply_changed(&pchg->psy->batt);
233 }
234 
lp8727_isr_func(int irq,void * ptr)235 static irqreturn_t lp8727_isr_func(int irq, void *ptr)
236 {
237 	struct lp8727_chg *pchg = ptr;
238 	unsigned long delay = msecs_to_jiffies(DEBOUNCE_MSEC);
239 
240 	queue_delayed_work(pchg->irqthread, &pchg->work, delay);
241 
242 	return IRQ_HANDLED;
243 }
244 
lp8727_intr_config(struct lp8727_chg * pchg)245 static int lp8727_intr_config(struct lp8727_chg *pchg)
246 {
247 	INIT_DELAYED_WORK(&pchg->work, lp8727_delayed_func);
248 
249 	pchg->irqthread = create_singlethread_workqueue("lp8727-irqthd");
250 	if (!pchg->irqthread) {
251 		dev_err(pchg->dev, "can not create thread for lp8727\n");
252 		return -ENOMEM;
253 	}
254 
255 	return request_threaded_irq(pchg->client->irq,
256 				NULL,
257 				lp8727_isr_func,
258 				IRQF_TRIGGER_FALLING,
259 				"lp8727_irq",
260 				pchg);
261 }
262 
263 static enum power_supply_property lp8727_charger_prop[] = {
264 	POWER_SUPPLY_PROP_ONLINE,
265 };
266 
267 static enum power_supply_property lp8727_battery_prop[] = {
268 	POWER_SUPPLY_PROP_STATUS,
269 	POWER_SUPPLY_PROP_HEALTH,
270 	POWER_SUPPLY_PROP_PRESENT,
271 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
272 	POWER_SUPPLY_PROP_CAPACITY,
273 	POWER_SUPPLY_PROP_TEMP,
274 };
275 
276 static char *battery_supplied_to[] = {
277 	"main_batt",
278 };
279 
lp8727_charger_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)280 static int lp8727_charger_get_property(struct power_supply *psy,
281 				       enum power_supply_property psp,
282 				       union power_supply_propval *val)
283 {
284 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
285 
286 	if (psp == POWER_SUPPLY_PROP_ONLINE)
287 		val->intval = lp8727_is_charger_attached(psy->name,
288 							 pchg->devid);
289 
290 	return 0;
291 }
292 
lp8727_battery_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)293 static int lp8727_battery_get_property(struct power_supply *psy,
294 				       enum power_supply_property psp,
295 				       union power_supply_propval *val)
296 {
297 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
298 	u8 read;
299 
300 	switch (psp) {
301 	case POWER_SUPPLY_PROP_STATUS:
302 		if (lp8727_is_charger_attached(psy->name, pchg->devid)) {
303 			lp8727_read_byte(pchg, STATUS1, &read);
304 			if (((read & CHGSTAT) >> 4) == EOC)
305 				val->intval = POWER_SUPPLY_STATUS_FULL;
306 			else
307 				val->intval = POWER_SUPPLY_STATUS_CHARGING;
308 		} else {
309 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
310 		}
311 		break;
312 	case POWER_SUPPLY_PROP_HEALTH:
313 		lp8727_read_byte(pchg, STATUS2, &read);
314 		read = (read & TEMP_STAT) >> 5;
315 		if (read >= 0x1 && read <= 0x3)
316 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
317 		else
318 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
319 		break;
320 	case POWER_SUPPLY_PROP_PRESENT:
321 		if (pchg->pdata->get_batt_present)
322 			val->intval = pchg->pdata->get_batt_present();
323 		break;
324 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
325 		if (pchg->pdata->get_batt_level)
326 			val->intval = pchg->pdata->get_batt_level();
327 		break;
328 	case POWER_SUPPLY_PROP_CAPACITY:
329 		if (pchg->pdata->get_batt_capacity)
330 			val->intval = pchg->pdata->get_batt_capacity();
331 		break;
332 	case POWER_SUPPLY_PROP_TEMP:
333 		if (pchg->pdata->get_batt_temp)
334 			val->intval = pchg->pdata->get_batt_temp();
335 		break;
336 	default:
337 		break;
338 	}
339 
340 	return 0;
341 }
342 
lp8727_charger_changed(struct power_supply * psy)343 static void lp8727_charger_changed(struct power_supply *psy)
344 {
345 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
346 	u8 val;
347 	u8 eoc_level, ichg;
348 
349 	if (lp8727_is_charger_attached(psy->name, pchg->devid)) {
350 		if (pchg->chg_parm) {
351 			eoc_level = pchg->chg_parm->eoc_level;
352 			ichg = pchg->chg_parm->ichg;
353 			val = (ichg << 4) | eoc_level;
354 			lp8727_write_byte(pchg, CHGCTRL2, val);
355 		}
356 	}
357 }
358 
lp8727_register_psy(struct lp8727_chg * pchg)359 static int lp8727_register_psy(struct lp8727_chg *pchg)
360 {
361 	struct lp8727_psy *psy;
362 
363 	psy = kzalloc(sizeof(*psy), GFP_KERNEL);
364 	if (!psy)
365 		goto err_mem;
366 
367 	pchg->psy = psy;
368 
369 	psy->ac.name = "ac";
370 	psy->ac.type = POWER_SUPPLY_TYPE_MAINS;
371 	psy->ac.properties = lp8727_charger_prop;
372 	psy->ac.num_properties = ARRAY_SIZE(lp8727_charger_prop);
373 	psy->ac.get_property = lp8727_charger_get_property;
374 	psy->ac.supplied_to = battery_supplied_to;
375 	psy->ac.num_supplicants = ARRAY_SIZE(battery_supplied_to);
376 
377 	if (power_supply_register(pchg->dev, &psy->ac))
378 		goto err_psy;
379 
380 	psy->usb.name = "usb";
381 	psy->usb.type = POWER_SUPPLY_TYPE_USB;
382 	psy->usb.properties = lp8727_charger_prop;
383 	psy->usb.num_properties = ARRAY_SIZE(lp8727_charger_prop);
384 	psy->usb.get_property = lp8727_charger_get_property;
385 	psy->usb.supplied_to = battery_supplied_to;
386 	psy->usb.num_supplicants = ARRAY_SIZE(battery_supplied_to);
387 
388 	if (power_supply_register(pchg->dev, &psy->usb))
389 		goto err_psy;
390 
391 	psy->batt.name = "main_batt";
392 	psy->batt.type = POWER_SUPPLY_TYPE_BATTERY;
393 	psy->batt.properties = lp8727_battery_prop;
394 	psy->batt.num_properties = ARRAY_SIZE(lp8727_battery_prop);
395 	psy->batt.get_property = lp8727_battery_get_property;
396 	psy->batt.external_power_changed = lp8727_charger_changed;
397 
398 	if (power_supply_register(pchg->dev, &psy->batt))
399 		goto err_psy;
400 
401 	return 0;
402 
403 err_mem:
404 	return -ENOMEM;
405 err_psy:
406 	kfree(psy);
407 	return -EPERM;
408 }
409 
lp8727_unregister_psy(struct lp8727_chg * pchg)410 static void lp8727_unregister_psy(struct lp8727_chg *pchg)
411 {
412 	struct lp8727_psy *psy = pchg->psy;
413 
414 	if (!psy)
415 		return;
416 
417 	power_supply_unregister(&psy->ac);
418 	power_supply_unregister(&psy->usb);
419 	power_supply_unregister(&psy->batt);
420 	kfree(psy);
421 }
422 
lp8727_probe(struct i2c_client * cl,const struct i2c_device_id * id)423 static int lp8727_probe(struct i2c_client *cl, const struct i2c_device_id *id)
424 {
425 	struct lp8727_chg *pchg;
426 	int ret;
427 
428 	if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
429 		return -EIO;
430 
431 	pchg = kzalloc(sizeof(*pchg), GFP_KERNEL);
432 	if (!pchg)
433 		return -ENOMEM;
434 
435 	pchg->client = cl;
436 	pchg->dev = &cl->dev;
437 	pchg->pdata = cl->dev.platform_data;
438 	i2c_set_clientdata(cl, pchg);
439 
440 	mutex_init(&pchg->xfer_lock);
441 
442 	ret = lp8727_init_device(pchg);
443 	if (ret) {
444 		dev_err(pchg->dev, "i2c communication err: %d", ret);
445 		goto error;
446 	}
447 
448 	ret = lp8727_intr_config(pchg);
449 	if (ret) {
450 		dev_err(pchg->dev, "irq handler err: %d", ret);
451 		goto error;
452 	}
453 
454 	ret = lp8727_register_psy(pchg);
455 	if (ret) {
456 		dev_err(pchg->dev, "power supplies register err: %d", ret);
457 		goto error;
458 	}
459 
460 	return 0;
461 
462 error:
463 	kfree(pchg);
464 	return ret;
465 }
466 
lp8727_remove(struct i2c_client * cl)467 static int __devexit lp8727_remove(struct i2c_client *cl)
468 {
469 	struct lp8727_chg *pchg = i2c_get_clientdata(cl);
470 
471 	lp8727_unregister_psy(pchg);
472 	free_irq(pchg->client->irq, pchg);
473 	flush_workqueue(pchg->irqthread);
474 	destroy_workqueue(pchg->irqthread);
475 	kfree(pchg);
476 	return 0;
477 }
478 
479 static const struct i2c_device_id lp8727_ids[] = {
480 	{"lp8727", 0},
481 	{ }
482 };
483 MODULE_DEVICE_TABLE(i2c, lp8727_ids);
484 
485 static struct i2c_driver lp8727_driver = {
486 	.driver = {
487 		   .name = "lp8727",
488 		   },
489 	.probe = lp8727_probe,
490 	.remove = __devexit_p(lp8727_remove),
491 	.id_table = lp8727_ids,
492 };
493 module_i2c_driver(lp8727_driver);
494 
495 MODULE_DESCRIPTION("TI/National Semiconductor LP8727 charger driver");
496 MODULE_AUTHOR("Woogyom Kim <milo.kim@ti.com>, "
497 	      "Daniel Jeong <daniel.jeong@ti.com>");
498 MODULE_LICENSE("GPL");
499