summaryrefslogtreecommitdiffstats
path: root/drivers/power/supply/bq24735-charger.c
blob: ab2f4bf8f603ffa947458be3b209ae66be22f757 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
/*
 * Battery charger driver for TI BQ24735
 *
 * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/power_supply.h>
#include <linux/slab.h>

#include <linux/power/bq24735-charger.h>

#define BQ24735_CHG_OPT			0x12
#define BQ24735_CHG_OPT_CHARGE_DISABLE	(1 << 0)
#define BQ24735_CHG_OPT_AC_PRESENT	(1 << 4)
#define BQ24735_CHARGE_CURRENT		0x14
#define BQ24735_CHARGE_CURRENT_MASK	0x1fc0
#define BQ24735_CHARGE_VOLTAGE		0x15
#define BQ24735_CHARGE_VOLTAGE_MASK	0x7ff0
#define BQ24735_INPUT_CURRENT		0x3f
#define BQ24735_INPUT_CURRENT_MASK	0x1f80
#define BQ24735_MANUFACTURER_ID		0xfe
#define BQ24735_DEVICE_ID		0xff

struct bq24735 {
	struct power_supply		*charger;
	struct power_supply_desc	charger_desc;
	struct i2c_client		*client;
	struct bq24735_platform		*pdata;
	struct mutex			lock;
	struct gpio_desc		*status_gpio;
	struct delayed_work		poll;
	u32				poll_interval;
	bool				charging;
};

static inline struct bq24735 *to_bq24735(struct power_supply *psy)
{
	return power_supply_get_drvdata(psy);
}

static enum power_supply_property bq24735_charger_properties[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_ONLINE,
};

static int bq24735_charger_property_is_writeable(struct power_supply *psy,
						 enum power_supply_property psp)
{
	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		return 1;
	default:
		break;
	}

	return 0;
}

static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
				     u16 value)
{
	return i2c_smbus_write_word_data(client, reg, value);
}

static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
{
	return i2c_smbus_read_word_data(client, reg);
}

static int bq24735_update_word(struct i2c_client *client, u8 reg,
			       u16 mask, u16 value)
{
	unsigned int tmp;
	int ret;

	ret = bq24735_read_word(client, reg);
	if (ret < 0)
		return ret;

	tmp = ret & ~mask;
	tmp |= value & mask;

	return bq24735_write_word(client, reg, tmp);
}

static int bq24735_config_charger(struct bq24735 *charger)
{
	struct bq24735_platform *pdata = charger->pdata;
	int ret;
	u16 value;

	if (pdata->ext_control)
		return 0;

	if (pdata->charge_current) {
		value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;

		ret = bq24735_write_word(charger->client,
					 BQ24735_CHARGE_CURRENT, value);
		if (ret < 0) {
			dev_err(&charger->client->dev,
				"Failed to write charger current : %d\n",
				ret);
			return ret;
		}
	}

	if (pdata->charge_voltage) {
		value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;

		ret = bq24735_write_word(charger->client,
					 BQ24735_CHARGE_VOLTAGE, value);
		if (ret < 0) {
			dev_err(&charger->client->dev,
				"Failed to write charger voltage : %d\n",
				ret);
			return ret;
		}
	}

	if (pdata->input_current) {
		value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;

		ret = bq24735_write_word(charger->client,
					 BQ24735_INPUT_CURRENT, value);
		if (ret < 0) {
			dev_err(&charger->client->dev,
				"Failed to write input current : %d\n",
				ret);
			return ret;
		}
	}

	return 0;
}

static inline int bq24735_enable_charging(struct bq24735 *charger)
{
	int ret;

	if (charger->pdata->ext_control)
		return 0;

	ret = bq24735_config_charger(charger);
	if (ret)
		return ret;

	return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
				   BQ24735_CHG_OPT_CHARGE_DISABLE, 0);
}

static inline int bq24735_disable_charging(struct bq24735 *charger)
{
	if (charger->pdata->ext_control)
		return 0;

	return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
				   BQ24735_CHG_OPT_CHARGE_DISABLE,
				   BQ24735_CHG_OPT_CHARGE_DISABLE);
}

static bool bq24735_charger_is_present(struct bq24735 *charger)
{
	if (charger->status_gpio) {
		return !gpiod_get_value_cansleep(charger->status_gpio);
	} else {
		int ac = 0;

		ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
		if (ac < 0) {
			dev_dbg(&charger->client->dev,
				"Failed to read charger options : %d\n",
				ac);
			return false;
		}
		return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
	}

	return false;
}

static int bq24735_charger_is_charging(struct bq24735 *charger)
{
	int ret;

	if (!bq24735_charger_is_present(charger))
		return 0;

	ret  = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
	if (ret < 0)
		return ret;

	return !(ret & BQ24735_CHG_OPT_CHARGE_DISABLE);
}

static void bq24735_update(struct bq24735 *charger)
{
	mutex_lock(&charger->lock);

	if (charger->charging && bq24735_charger_is_present(charger))
		bq24735_enable_charging(charger);
	else
		bq24735_disable_charging(charger);

	mutex_unlock(&charger->lock);

	power_supply_changed(charger->charger);
}

static irqreturn_t bq24735_charger_isr(int irq, void *devid)
{
	struct power_supply *psy = devid;
	struct bq24735 *charger = to_bq24735(psy);

	bq24735_update(charger);

	return IRQ_HANDLED;
}

static void bq24735_poll(struct work_struct *work)
{
	struct bq24735 *charger = container_of(work, struct bq24735, poll.work);

	bq24735_update(charger);

	schedule_delayed_work(&charger->poll,
			      msecs_to_jiffies(charger->poll_interval));
}

static int bq24735_charger_get_property(struct power_supply *psy,
					enum power_supply_property psp,
					union power_supply_propval *val)
{
	struct bq24735 *charger = to_bq24735(psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_ONLINE:
		val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
		break;
	case POWER_SUPPLY_PROP_STATUS:
		switch (bq24735_charger_is_charging(charger)) {
		case 1:
			val->intval = POWER_SUPPLY_STATUS_CHARGING;
			break;
		case 0:
			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
			break;
		default:
			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
			break;
		}
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int bq24735_charger_set_property(struct power_supply *psy,
					enum power_supply_property psp,
					const union power_supply_propval *val)
{
	struct bq24735 *charger = to_bq24735(psy);
	int ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		switch (val->intval) {
		case POWER_SUPPLY_STATUS_CHARGING:
			mutex_lock(&charger->lock);
			charger->charging = true;
			ret = bq24735_enable_charging(charger);
			mutex_unlock(&charger->lock);
			if (ret)
				return ret;
			break;
		case POWER_SUPPLY_STATUS_DISCHARGING:
		case POWER_SUPPLY_STATUS_NOT_CHARGING:
			mutex_lock(&charger->lock);
			charger->charging = false;
			ret = bq24735_disable_charging(charger);
			mutex_unlock(&charger->lock);
			if (ret)
				return ret;
			break;
		default:
			return -EINVAL;
		}
		power_supply_changed(psy);
		break;
	default:
		return -EPERM;
	}

	return 0;
}

static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
{
	struct bq24735_platform *pdata;
	struct device_node *np = client->dev.of_node;
	u32 val;
	int ret;

	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata) {
		dev_err(&client->dev,
			"Memory alloc for bq24735 pdata failed\n");
		return NULL;
	}

	ret = of_property_read_u32(np, "ti,charge-current", &val);
	if (!ret)
		pdata->charge_current = val;

	ret = of_property_read_u32(np, "ti,charge-voltage", &val);
	if (!ret)
		pdata->charge_voltage = val;

	ret = of_property_read_u32(np, "ti,input-current", &val);
	if (!ret)
		pdata->input_current = val;

	pdata->ext_control = of_property_read_bool(np, "ti,external-control");

	return pdata;
}

static int bq24735_charger_probe(struct i2c_client *client,
				 const struct i2c_device_id *id)
{
	int ret;
	struct bq24735 *charger;
	struct power_supply_desc *supply_desc;
	struct power_supply_config psy_cfg = {};
	char *name;

	charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
	if (!charger)
		return -ENOMEM;

	mutex_init(&charger->lock);
	charger->charging = true;
	charger->pdata = client->dev.platform_data;

	if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
		charger->pdata = bq24735_parse_dt_data(client);

	if (!charger->pdata) {
		dev_err(&client->dev, "no platform data provided\n");
		return -EINVAL;
	}

	name = (char *)charger->pdata->name;
	if (!name) {
		name = devm_kasprintf(&client->dev, GFP_KERNEL,
				      "bq24735@%s",
				      dev_name(&client->dev));
		if (!name) {
			dev_err(&client->dev, "Failed to alloc device name\n");
			return -ENOMEM;
		}
	}

	charger->client = client;

	supply_desc = &charger->charger_desc;

	supply_desc->name = name;
	supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
	supply_desc->properties = bq24735_charger_properties;
	supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
	supply_desc->get_property = bq24735_charger_get_property;
	supply_desc->set_property = bq24735_charger_set_property;
	supply_desc->property_is_writeable =
				bq24735_charger_property_is_writeable;

	psy_cfg.supplied_to = charger->pdata->supplied_to;
	psy_cfg.num_supplicants = charger->pdata->num_supplicants;
	psy_cfg.of_node = client->dev.of_node;
	psy_cfg.drv_data = charger;

	i2c_set_clientdata(client, charger);

	charger->status_gpio = devm_gpiod_get_optional(&client->dev,
						       "ti,ac-detect",
						       GPIOD_IN);
	if (IS_ERR(charger->status_gpio)) {
		ret = PTR_ERR(charger->status_gpio);
		dev_err(&client->dev, "Getting gpio failed: %d\n", ret);
		return ret;
	}

	if (bq24735_charger_is_present(charger)) {
		ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
		if (ret < 0) {
			dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
				ret);
			return ret;
		} else if (ret != 0x0040) {
			dev_err(&client->dev,
				"manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
			return -ENODEV;
		}

		ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
		if (ret < 0) {
			dev_err(&client->dev, "Failed to read device id : %d\n", ret);
			return ret;
		} else if (ret != 0x000B) {
			dev_err(&client->dev,
				"device id mismatch. 0x000b != 0x%04x\n", ret);
			return -ENODEV;
		}

		ret = bq24735_enable_charging(charger);
		if (ret < 0) {
			dev_err(&client->dev, "Failed to enable charging\n");
			return ret;
		}
	}

	charger->charger = devm_power_supply_register(&client->dev, supply_desc,
						      &psy_cfg);
	if (IS_ERR(charger->charger)) {
		ret = PTR_ERR(charger->charger);
		dev_err(&client->dev, "Failed to register power supply: %d\n",
			ret);
		return ret;
	}

	if (client->irq) {
		ret = devm_request_threaded_irq(&client->dev, client->irq,
						NULL, bq24735_charger_isr,
						IRQF_TRIGGER_RISING |
						IRQF_TRIGGER_FALLING |
						IRQF_ONESHOT,
						supply_desc->name,
						charger->charger);
		if (ret) {
			dev_err(&client->dev,
				"Unable to register IRQ %d err %d\n",
				client->irq, ret);
			return ret;
		}
	} else {
		ret = device_property_read_u32(&client->dev, "poll-interval",
					       &charger->poll_interval);
		if (ret)
			return 0;
		if (!charger->poll_interval)
			return 0;

		INIT_DELAYED_WORK(&charger->poll, bq24735_poll);
		schedule_delayed_work(&charger->poll,
				      msecs_to_jiffies(charger->poll_interval));
	}

	return 0;
}

static int bq24735_charger_remove(struct i2c_client *client)
{
	struct bq24735 *charger = i2c_get_clientdata(client);

	if (charger->poll_interval)
		cancel_delayed_work_sync(&charger->poll);

	return 0;
}

static const struct i2c_device_id bq24735_charger_id[] = {
	{ "bq24735-charger", 0 },
	{}
};
MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);

static const struct of_device_id bq24735_match_ids[] = {
	{ .compatible = "ti,bq24735", },
	{ /* end */ }
};
MODULE_DEVICE_TABLE(of, bq24735_match_ids);

static struct i2c_driver bq24735_charger_driver = {
	.driver = {
		.name = "bq24735-charger",
		.of_match_table = bq24735_match_ids,
	},
	.probe = bq24735_charger_probe,
	.remove = bq24735_charger_remove,
	.id_table = bq24735_charger_id,
};

module_i2c_driver(bq24735_charger_driver);

MODULE_DESCRIPTION("bq24735 battery charging driver");
MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
MODULE_LICENSE("GPL v2");