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20#include <linux/devm-helpers.h>
21#include <linux/err.h>
22#include <linux/i2c.h>
23#include <linux/init.h>
24#include <linux/interrupt.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/of.h>
28#include <linux/gpio/consumer.h>
29#include <linux/power_supply.h>
30#include <linux/slab.h>
31
32#include <linux/power/bq24735-charger.h>
33
34
35#define BQ24735_CHARGE_OPT 0x12
36#define BQ24735_CHARGE_CURRENT 0x14
37#define BQ24735_CHARGE_CURRENT_MASK 0x1fc0
38#define BQ24735_CHARGE_VOLTAGE 0x15
39#define BQ24735_CHARGE_VOLTAGE_MASK 0x7ff0
40#define BQ24735_INPUT_CURRENT 0x3f
41#define BQ24735_INPUT_CURRENT_MASK 0x1f80
42#define BQ24735_MANUFACTURER_ID 0xfe
43#define BQ24735_DEVICE_ID 0xff
44
45
46#define BQ24735_CHARGE_OPT_CHG_DISABLE (1 << 0)
47#define BQ24735_CHARGE_OPT_AC_PRESENT (1 << 4)
48
49struct bq24735 {
50 struct power_supply *charger;
51 struct power_supply_desc charger_desc;
52 struct i2c_client *client;
53 struct bq24735_platform *pdata;
54 struct mutex lock;
55 struct gpio_desc *status_gpio;
56 struct delayed_work poll;
57 u32 poll_interval;
58 bool charging;
59};
60
61static inline struct bq24735 *to_bq24735(struct power_supply *psy)
62{
63 return power_supply_get_drvdata(psy);
64}
65
66static enum power_supply_property bq24735_charger_properties[] = {
67 POWER_SUPPLY_PROP_STATUS,
68 POWER_SUPPLY_PROP_ONLINE,
69};
70
71static int bq24735_charger_property_is_writeable(struct power_supply *psy,
72 enum power_supply_property psp)
73{
74 switch (psp) {
75 case POWER_SUPPLY_PROP_STATUS:
76 return 1;
77 default:
78 break;
79 }
80
81 return 0;
82}
83
84static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
85 u16 value)
86{
87 return i2c_smbus_write_word_data(client, reg, value);
88}
89
90static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
91{
92 return i2c_smbus_read_word_data(client, reg);
93}
94
95static int bq24735_update_word(struct i2c_client *client, u8 reg,
96 u16 mask, u16 value)
97{
98 unsigned int tmp;
99 int ret;
100
101 ret = bq24735_read_word(client, reg);
102 if (ret < 0)
103 return ret;
104
105 tmp = ret & ~mask;
106 tmp |= value & mask;
107
108 return bq24735_write_word(client, reg, tmp);
109}
110
111static int bq24735_config_charger(struct bq24735 *charger)
112{
113 struct bq24735_platform *pdata = charger->pdata;
114 int ret;
115 u16 value;
116
117 if (pdata->ext_control)
118 return 0;
119
120 if (pdata->charge_current) {
121 value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;
122
123 ret = bq24735_write_word(charger->client,
124 BQ24735_CHARGE_CURRENT, value);
125 if (ret < 0) {
126 dev_err(&charger->client->dev,
127 "Failed to write charger current : %d\n",
128 ret);
129 return ret;
130 }
131 }
132
133 if (pdata->charge_voltage) {
134 value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;
135
136 ret = bq24735_write_word(charger->client,
137 BQ24735_CHARGE_VOLTAGE, value);
138 if (ret < 0) {
139 dev_err(&charger->client->dev,
140 "Failed to write charger voltage : %d\n",
141 ret);
142 return ret;
143 }
144 }
145
146 if (pdata->input_current) {
147 value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;
148
149 ret = bq24735_write_word(charger->client,
150 BQ24735_INPUT_CURRENT, value);
151 if (ret < 0) {
152 dev_err(&charger->client->dev,
153 "Failed to write input current : %d\n",
154 ret);
155 return ret;
156 }
157 }
158
159 return 0;
160}
161
162static inline int bq24735_enable_charging(struct bq24735 *charger)
163{
164 int ret;
165
166 if (charger->pdata->ext_control)
167 return 0;
168
169 ret = bq24735_config_charger(charger);
170 if (ret)
171 return ret;
172
173 return bq24735_update_word(charger->client, BQ24735_CHARGE_OPT,
174 BQ24735_CHARGE_OPT_CHG_DISABLE, 0);
175}
176
177static inline int bq24735_disable_charging(struct bq24735 *charger)
178{
179 if (charger->pdata->ext_control)
180 return 0;
181
182 return bq24735_update_word(charger->client, BQ24735_CHARGE_OPT,
183 BQ24735_CHARGE_OPT_CHG_DISABLE,
184 BQ24735_CHARGE_OPT_CHG_DISABLE);
185}
186
187static bool bq24735_charger_is_present(struct bq24735 *charger)
188{
189 if (charger->status_gpio) {
190 return !gpiod_get_value_cansleep(charger->status_gpio);
191 } else {
192 int ac = 0;
193
194 ac = bq24735_read_word(charger->client, BQ24735_CHARGE_OPT);
195 if (ac < 0) {
196 dev_dbg(&charger->client->dev,
197 "Failed to read charger options : %d\n",
198 ac);
199 return false;
200 }
201 return (ac & BQ24735_CHARGE_OPT_AC_PRESENT) ? true : false;
202 }
203
204 return false;
205}
206
207static int bq24735_charger_is_charging(struct bq24735 *charger)
208{
209 int ret;
210
211 if (!bq24735_charger_is_present(charger))
212 return 0;
213
214 ret = bq24735_read_word(charger->client, BQ24735_CHARGE_OPT);
215 if (ret < 0)
216 return ret;
217
218 return !(ret & BQ24735_CHARGE_OPT_CHG_DISABLE);
219}
220
221static void bq24735_update(struct bq24735 *charger)
222{
223 mutex_lock(&charger->lock);
224
225 if (charger->charging && bq24735_charger_is_present(charger))
226 bq24735_enable_charging(charger);
227 else
228 bq24735_disable_charging(charger);
229
230 mutex_unlock(&charger->lock);
231
232 power_supply_changed(charger->charger);
233}
234
235static irqreturn_t bq24735_charger_isr(int irq, void *devid)
236{
237 struct power_supply *psy = devid;
238 struct bq24735 *charger = to_bq24735(psy);
239
240 bq24735_update(charger);
241
242 return IRQ_HANDLED;
243}
244
245static void bq24735_poll(struct work_struct *work)
246{
247 struct bq24735 *charger = container_of(work, struct bq24735, poll.work);
248
249 bq24735_update(charger);
250
251 schedule_delayed_work(&charger->poll,
252 msecs_to_jiffies(charger->poll_interval));
253}
254
255static int bq24735_charger_get_property(struct power_supply *psy,
256 enum power_supply_property psp,
257 union power_supply_propval *val)
258{
259 struct bq24735 *charger = to_bq24735(psy);
260
261 switch (psp) {
262 case POWER_SUPPLY_PROP_ONLINE:
263 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
264 break;
265 case POWER_SUPPLY_PROP_STATUS:
266 switch (bq24735_charger_is_charging(charger)) {
267 case 1:
268 val->intval = POWER_SUPPLY_STATUS_CHARGING;
269 break;
270 case 0:
271 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
272 break;
273 default:
274 val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
275 break;
276 }
277 break;
278 default:
279 return -EINVAL;
280 }
281
282 return 0;
283}
284
285static int bq24735_charger_set_property(struct power_supply *psy,
286 enum power_supply_property psp,
287 const union power_supply_propval *val)
288{
289 struct bq24735 *charger = to_bq24735(psy);
290 int ret;
291
292 switch (psp) {
293 case POWER_SUPPLY_PROP_STATUS:
294 switch (val->intval) {
295 case POWER_SUPPLY_STATUS_CHARGING:
296 mutex_lock(&charger->lock);
297 charger->charging = true;
298 ret = bq24735_enable_charging(charger);
299 mutex_unlock(&charger->lock);
300 if (ret)
301 return ret;
302 break;
303 case POWER_SUPPLY_STATUS_DISCHARGING:
304 case POWER_SUPPLY_STATUS_NOT_CHARGING:
305 mutex_lock(&charger->lock);
306 charger->charging = false;
307 ret = bq24735_disable_charging(charger);
308 mutex_unlock(&charger->lock);
309 if (ret)
310 return ret;
311 break;
312 default:
313 return -EINVAL;
314 }
315 power_supply_changed(psy);
316 break;
317 default:
318 return -EPERM;
319 }
320
321 return 0;
322}
323
324static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
325{
326 struct bq24735_platform *pdata;
327 struct device_node *np = client->dev.of_node;
328 u32 val;
329 int ret;
330
331 pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
332 if (!pdata) {
333 dev_err(&client->dev,
334 "Memory alloc for bq24735 pdata failed\n");
335 return NULL;
336 }
337
338 ret = of_property_read_u32(np, "ti,charge-current", &val);
339 if (!ret)
340 pdata->charge_current = val;
341
342 ret = of_property_read_u32(np, "ti,charge-voltage", &val);
343 if (!ret)
344 pdata->charge_voltage = val;
345
346 ret = of_property_read_u32(np, "ti,input-current", &val);
347 if (!ret)
348 pdata->input_current = val;
349
350 pdata->ext_control = of_property_read_bool(np, "ti,external-control");
351
352 return pdata;
353}
354
355static int bq24735_charger_probe(struct i2c_client *client,
356 const struct i2c_device_id *id)
357{
358 int ret;
359 struct bq24735 *charger;
360 struct power_supply_desc *supply_desc;
361 struct power_supply_config psy_cfg = {};
362 char *name;
363
364 charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
365 if (!charger)
366 return -ENOMEM;
367
368 mutex_init(&charger->lock);
369 charger->charging = true;
370 charger->pdata = client->dev.platform_data;
371
372 if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
373 charger->pdata = bq24735_parse_dt_data(client);
374
375 if (!charger->pdata) {
376 dev_err(&client->dev, "no platform data provided\n");
377 return -EINVAL;
378 }
379
380 name = (char *)charger->pdata->name;
381 if (!name) {
382 name = devm_kasprintf(&client->dev, GFP_KERNEL,
383 "bq24735@%s",
384 dev_name(&client->dev));
385 if (!name) {
386 dev_err(&client->dev, "Failed to alloc device name\n");
387 return -ENOMEM;
388 }
389 }
390
391 charger->client = client;
392
393 supply_desc = &charger->charger_desc;
394
395 supply_desc->name = name;
396 supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
397 supply_desc->properties = bq24735_charger_properties;
398 supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
399 supply_desc->get_property = bq24735_charger_get_property;
400 supply_desc->set_property = bq24735_charger_set_property;
401 supply_desc->property_is_writeable =
402 bq24735_charger_property_is_writeable;
403
404 psy_cfg.supplied_to = charger->pdata->supplied_to;
405 psy_cfg.num_supplicants = charger->pdata->num_supplicants;
406 psy_cfg.of_node = client->dev.of_node;
407 psy_cfg.drv_data = charger;
408
409 i2c_set_clientdata(client, charger);
410
411 charger->status_gpio = devm_gpiod_get_optional(&client->dev,
412 "ti,ac-detect",
413 GPIOD_IN);
414 if (IS_ERR(charger->status_gpio)) {
415 ret = PTR_ERR(charger->status_gpio);
416 dev_err(&client->dev, "Getting gpio failed: %d\n", ret);
417 return ret;
418 }
419
420 if (bq24735_charger_is_present(charger)) {
421 ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
422 if (ret < 0) {
423 dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
424 ret);
425 return ret;
426 } else if (ret != 0x0040) {
427 dev_err(&client->dev,
428 "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
429 return -ENODEV;
430 }
431
432 ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
433 if (ret < 0) {
434 dev_err(&client->dev, "Failed to read device id : %d\n", ret);
435 return ret;
436 } else if (ret != 0x000B) {
437 dev_err(&client->dev,
438 "device id mismatch. 0x000b != 0x%04x\n", ret);
439 return -ENODEV;
440 }
441
442 ret = bq24735_enable_charging(charger);
443 if (ret < 0) {
444 dev_err(&client->dev, "Failed to enable charging\n");
445 return ret;
446 }
447 }
448
449 charger->charger = devm_power_supply_register(&client->dev, supply_desc,
450 &psy_cfg);
451 if (IS_ERR(charger->charger)) {
452 ret = PTR_ERR(charger->charger);
453 dev_err(&client->dev, "Failed to register power supply: %d\n",
454 ret);
455 return ret;
456 }
457
458 if (client->irq) {
459 ret = devm_request_threaded_irq(&client->dev, client->irq,
460 NULL, bq24735_charger_isr,
461 IRQF_TRIGGER_RISING |
462 IRQF_TRIGGER_FALLING |
463 IRQF_ONESHOT,
464 supply_desc->name,
465 charger->charger);
466 if (ret) {
467 dev_err(&client->dev,
468 "Unable to register IRQ %d err %d\n",
469 client->irq, ret);
470 return ret;
471 }
472 } else {
473 ret = device_property_read_u32(&client->dev, "poll-interval",
474 &charger->poll_interval);
475 if (ret)
476 return 0;
477 if (!charger->poll_interval)
478 return 0;
479
480 ret = devm_delayed_work_autocancel(&client->dev, &charger->poll,
481 bq24735_poll);
482 if (ret)
483 return ret;
484
485 schedule_delayed_work(&charger->poll,
486 msecs_to_jiffies(charger->poll_interval));
487 }
488
489 return 0;
490}
491
492static const struct i2c_device_id bq24735_charger_id[] = {
493 { "bq24735-charger", 0 },
494 {}
495};
496MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
497
498static const struct of_device_id bq24735_match_ids[] = {
499 { .compatible = "ti,bq24735", },
500 { }
501};
502MODULE_DEVICE_TABLE(of, bq24735_match_ids);
503
504static struct i2c_driver bq24735_charger_driver = {
505 .driver = {
506 .name = "bq24735-charger",
507 .of_match_table = bq24735_match_ids,
508 },
509 .probe = bq24735_charger_probe,
510 .id_table = bq24735_charger_id,
511};
512
513module_i2c_driver(bq24735_charger_driver);
514
515MODULE_DESCRIPTION("bq24735 battery charging driver");
516MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
517MODULE_LICENSE("GPL v2");
518
