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20#include <linux/err.h>
21#include <linux/gpio.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/of_gpio.h>
29#include <linux/power_supply.h>
30#include <linux/slab.h>
31
32#include <linux/power/bq24735-charger.h>
33
34#define BQ24735_CHG_OPT 0x12
35#define BQ24735_CHG_OPT_CHARGE_DISABLE (1 << 0)
36#define BQ24735_CHG_OPT_AC_PRESENT (1 << 4)
37#define BQ24735_CHARGE_CURRENT 0x14
38#define BQ24735_CHARGE_CURRENT_MASK 0x1fc0
39#define BQ24735_CHARGE_VOLTAGE 0x15
40#define BQ24735_CHARGE_VOLTAGE_MASK 0x7ff0
41#define BQ24735_INPUT_CURRENT 0x3f
42#define BQ24735_INPUT_CURRENT_MASK 0x1f80
43#define BQ24735_MANUFACTURER_ID 0xfe
44#define BQ24735_DEVICE_ID 0xff
45
46struct bq24735 {
47 struct power_supply *charger;
48 struct power_supply_desc charger_desc;
49 struct i2c_client *client;
50 struct bq24735_platform *pdata;
51};
52
53static inline struct bq24735 *to_bq24735(struct power_supply *psy)
54{
55 return power_supply_get_drvdata(psy);
56}
57
58static enum power_supply_property bq24735_charger_properties[] = {
59 POWER_SUPPLY_PROP_ONLINE,
60};
61
62static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
63 u16 value)
64{
65 return i2c_smbus_write_word_data(client, reg, le16_to_cpu(value));
66}
67
68static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
69{
70 s32 ret = i2c_smbus_read_word_data(client, reg);
71
72 return ret < 0 ? ret : le16_to_cpu(ret);
73}
74
75static int bq24735_update_word(struct i2c_client *client, u8 reg,
76 u16 mask, u16 value)
77{
78 unsigned int tmp;
79 int ret;
80
81 ret = bq24735_read_word(client, reg);
82 if (ret < 0)
83 return ret;
84
85 tmp = ret & ~mask;
86 tmp |= value & mask;
87
88 return bq24735_write_word(client, reg, tmp);
89}
90
91static inline int bq24735_enable_charging(struct bq24735 *charger)
92{
93 return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
94 BQ24735_CHG_OPT_CHARGE_DISABLE,
95 ~BQ24735_CHG_OPT_CHARGE_DISABLE);
96}
97
98static inline int bq24735_disable_charging(struct bq24735 *charger)
99{
100 return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
101 BQ24735_CHG_OPT_CHARGE_DISABLE,
102 BQ24735_CHG_OPT_CHARGE_DISABLE);
103}
104
105static int bq24735_config_charger(struct bq24735 *charger)
106{
107 struct bq24735_platform *pdata = charger->pdata;
108 int ret;
109 u16 value;
110
111 if (pdata->charge_current) {
112 value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;
113
114 ret = bq24735_write_word(charger->client,
115 BQ24735_CHARGE_CURRENT, value);
116 if (ret < 0) {
117 dev_err(&charger->client->dev,
118 "Failed to write charger current : %d\n",
119 ret);
120 return ret;
121 }
122 }
123
124 if (pdata->charge_voltage) {
125 value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;
126
127 ret = bq24735_write_word(charger->client,
128 BQ24735_CHARGE_VOLTAGE, value);
129 if (ret < 0) {
130 dev_err(&charger->client->dev,
131 "Failed to write charger voltage : %d\n",
132 ret);
133 return ret;
134 }
135 }
136
137 if (pdata->input_current) {
138 value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;
139
140 ret = bq24735_write_word(charger->client,
141 BQ24735_INPUT_CURRENT, value);
142 if (ret < 0) {
143 dev_err(&charger->client->dev,
144 "Failed to write input current : %d\n",
145 ret);
146 return ret;
147 }
148 }
149
150 return 0;
151}
152
153static bool bq24735_charger_is_present(struct bq24735 *charger)
154{
155 struct bq24735_platform *pdata = charger->pdata;
156 int ret;
157
158 if (pdata->status_gpio_valid) {
159 ret = gpio_get_value_cansleep(pdata->status_gpio);
160 return ret ^= pdata->status_gpio_active_low == 0;
161 } else {
162 int ac = 0;
163
164 ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
165 if (ac < 0) {
166 dev_err(&charger->client->dev,
167 "Failed to read charger options : %d\n",
168 ac);
169 return false;
170 }
171 return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
172 }
173
174 return false;
175}
176
177static irqreturn_t bq24735_charger_isr(int irq, void *devid)
178{
179 struct power_supply *psy = devid;
180 struct bq24735 *charger = to_bq24735(psy);
181
182 if (bq24735_charger_is_present(charger))
183 bq24735_enable_charging(charger);
184 else
185 bq24735_disable_charging(charger);
186
187 power_supply_changed(psy);
188
189 return IRQ_HANDLED;
190}
191
192static int bq24735_charger_get_property(struct power_supply *psy,
193 enum power_supply_property psp,
194 union power_supply_propval *val)
195{
196 struct bq24735 *charger = to_bq24735(psy);
197
198 switch (psp) {
199 case POWER_SUPPLY_PROP_ONLINE:
200 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
201 break;
202 default:
203 return -EINVAL;
204 }
205
206 return 0;
207}
208
209static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
210{
211 struct bq24735_platform *pdata;
212 struct device_node *np = client->dev.of_node;
213 u32 val;
214 int ret;
215 enum of_gpio_flags flags;
216
217 pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
218 if (!pdata) {
219 dev_err(&client->dev,
220 "Memory alloc for bq24735 pdata failed\n");
221 return NULL;
222 }
223
224 pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-gpios",
225 0, &flags);
226
227 if (flags & OF_GPIO_ACTIVE_LOW)
228 pdata->status_gpio_active_low = 1;
229
230 ret = of_property_read_u32(np, "ti,charge-current", &val);
231 if (!ret)
232 pdata->charge_current = val;
233
234 ret = of_property_read_u32(np, "ti,charge-voltage", &val);
235 if (!ret)
236 pdata->charge_voltage = val;
237
238 ret = of_property_read_u32(np, "ti,input-current", &val);
239 if (!ret)
240 pdata->input_current = val;
241
242 return pdata;
243}
244
245static int bq24735_charger_probe(struct i2c_client *client,
246 const struct i2c_device_id *id)
247{
248 int ret;
249 struct bq24735 *charger;
250 struct power_supply_desc *supply_desc;
251 struct power_supply_config psy_cfg = {};
252 char *name;
253
254 charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
255 if (!charger)
256 return -ENOMEM;
257
258 charger->pdata = client->dev.platform_data;
259
260 if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
261 charger->pdata = bq24735_parse_dt_data(client);
262
263 if (!charger->pdata) {
264 dev_err(&client->dev, "no platform data provided\n");
265 return -EINVAL;
266 }
267
268 name = (char *)charger->pdata->name;
269 if (!name) {
270 name = kasprintf(GFP_KERNEL, "bq24735@%s",
271 dev_name(&client->dev));
272 if (!name) {
273 dev_err(&client->dev, "Failed to alloc device name\n");
274 return -ENOMEM;
275 }
276 }
277
278 charger->client = client;
279
280 supply_desc = &charger->charger_desc;
281
282 supply_desc->name = name;
283 supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
284 supply_desc->properties = bq24735_charger_properties;
285 supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
286 supply_desc->get_property = bq24735_charger_get_property;
287
288 psy_cfg.supplied_to = charger->pdata->supplied_to;
289 psy_cfg.num_supplicants = charger->pdata->num_supplicants;
290 psy_cfg.of_node = client->dev.of_node;
291 psy_cfg.drv_data = charger;
292
293 i2c_set_clientdata(client, charger);
294
295 ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
296 if (ret < 0) {
297 dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
298 ret);
299 goto err_free_name;
300 } else if (ret != 0x0040) {
301 dev_err(&client->dev,
302 "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
303 ret = -ENODEV;
304 goto err_free_name;
305 }
306
307 ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
308 if (ret < 0) {
309 dev_err(&client->dev, "Failed to read device id : %d\n", ret);
310 goto err_free_name;
311 } else if (ret != 0x000B) {
312 dev_err(&client->dev,
313 "device id mismatch. 0x000b != 0x%04x\n", ret);
314 ret = -ENODEV;
315 goto err_free_name;
316 }
317
318 if (gpio_is_valid(charger->pdata->status_gpio)) {
319 ret = devm_gpio_request(&client->dev,
320 charger->pdata->status_gpio,
321 name);
322 if (ret) {
323 dev_err(&client->dev,
324 "Failed GPIO request for GPIO %d: %d\n",
325 charger->pdata->status_gpio, ret);
326 }
327
328 charger->pdata->status_gpio_valid = !ret;
329 }
330
331 ret = bq24735_config_charger(charger);
332 if (ret < 0) {
333 dev_err(&client->dev, "failed in configuring charger");
334 goto err_free_name;
335 }
336
337
338 if (bq24735_charger_is_present(charger)) {
339 ret = bq24735_enable_charging(charger);
340 if (ret < 0) {
341 dev_err(&client->dev, "Failed to enable charging\n");
342 goto err_free_name;
343 }
344 }
345
346 charger->charger = power_supply_register(&client->dev, supply_desc,
347 &psy_cfg);
348 if (IS_ERR(charger->charger)) {
349 ret = PTR_ERR(charger->charger);
350 dev_err(&client->dev, "Failed to register power supply: %d\n",
351 ret);
352 goto err_free_name;
353 }
354
355 if (client->irq) {
356 ret = devm_request_threaded_irq(&client->dev, client->irq,
357 NULL, bq24735_charger_isr,
358 IRQF_TRIGGER_RISING |
359 IRQF_TRIGGER_FALLING |
360 IRQF_ONESHOT,
361 supply_desc->name,
362 charger->charger);
363 if (ret) {
364 dev_err(&client->dev,
365 "Unable to register IRQ %d err %d\n",
366 client->irq, ret);
367 goto err_unregister_supply;
368 }
369 }
370
371 return 0;
372err_unregister_supply:
373 power_supply_unregister(charger->charger);
374err_free_name:
375 if (name != charger->pdata->name)
376 kfree(name);
377
378 return ret;
379}
380
381static int bq24735_charger_remove(struct i2c_client *client)
382{
383 struct bq24735 *charger = i2c_get_clientdata(client);
384
385 if (charger->client->irq)
386 devm_free_irq(&charger->client->dev, charger->client->irq,
387 &charger->charger);
388
389 power_supply_unregister(charger->charger);
390
391 if (charger->charger_desc.name != charger->pdata->name)
392 kfree(charger->charger_desc.name);
393
394 return 0;
395}
396
397static const struct i2c_device_id bq24735_charger_id[] = {
398 { "bq24735-charger", 0 },
399 {}
400};
401MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
402
403static const struct of_device_id bq24735_match_ids[] = {
404 { .compatible = "ti,bq24735", },
405 { }
406};
407MODULE_DEVICE_TABLE(of, bq24735_match_ids);
408
409static struct i2c_driver bq24735_charger_driver = {
410 .driver = {
411 .name = "bq24735-charger",
412 .owner = THIS_MODULE,
413 .of_match_table = bq24735_match_ids,
414 },
415 .probe = bq24735_charger_probe,
416 .remove = bq24735_charger_remove,
417 .id_table = bq24735_charger_id,
418};
419
420module_i2c_driver(bq24735_charger_driver);
421
422MODULE_DESCRIPTION("bq24735 battery charging driver");
423MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
424MODULE_LICENSE("GPL v2");
425
