drivers/power/supply/bq24735-charger.c

   1 /*
   2  * Battery charger driver for TI BQ24735
   3  *
   4  * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation;
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  18  */
  19
  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/gpio/consumer.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
  46 struct bq24735 {
  47         struct power_supply             *charger;
  48         struct power_supply_desc        charger_desc;
  49         struct i2c_client               *client;
  50         struct bq24735_platform         *pdata;
  51         struct mutex                    lock;
  52         struct gpio_desc                *status_gpio;
  53         struct delayed_work             poll;
  54         u32                             poll_interval;
  55         bool                            charging;
  56 };
  57
  58 static inline struct bq24735 *to_bq24735(struct power_supply *psy)
  59 {
  60         return power_supply_get_drvdata(psy);
  61 }
  62
  63 static enum power_supply_property bq24735_charger_properties[] = {
  64         POWER_SUPPLY_PROP_STATUS,
  65         POWER_SUPPLY_PROP_ONLINE,
  66 };
  67
  68 static int bq24735_charger_property_is_writeable(struct power_supply *psy,
  69                                                  enum power_supply_property psp)
  70 {
  71         switch (psp) {
  72         case POWER_SUPPLY_PROP_STATUS:
  73                 return 1;
  74         default:
  75                 break;
  76         }
  77
  78         return 0;
  79 }
  80
  81 static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
  82                                      u16 value)
  83 {
  84         return i2c_smbus_write_word_data(client, reg, le16_to_cpu(value));
  85 }
  86
  87 static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
  88 {
  89         s32 ret = i2c_smbus_read_word_data(client, reg);
  90
  91         return ret < 0 ? ret : le16_to_cpu(ret);
  92 }
  93
  94 static int bq24735_update_word(struct i2c_client *client, u8 reg,
  95                                u16 mask, u16 value)
  96 {
  97         unsigned int tmp;
  98         int ret;
  99
 100         ret = bq24735_read_word(client, reg);
 101         if (ret < 0)
 102                 return ret;
 103
 104         tmp = ret & ~mask;
 105         tmp |= value & mask;
 106
 107         return bq24735_write_word(client, reg, tmp);
 108 }
 109
 110 static int bq24735_config_charger(struct bq24735 *charger)
 111 {
 112         struct bq24735_platform *pdata = charger->pdata;
 113         int ret;
 114         u16 value;
 115
 116         if (pdata->ext_control)
 117                 return 0;
 118
 119         if (pdata->charge_current) {
 120                 value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;
 121
 122                 ret = bq24735_write_word(charger->client,
 123                                          BQ24735_CHARGE_CURRENT, value);
 124                 if (ret < 0) {
 125                         dev_err(&charger->client->dev,
 126                                 "Failed to write charger current : %d\n",
 127                                 ret);
 128                         return ret;
 129                 }
 130         }
 131
 132         if (pdata->charge_voltage) {
 133                 value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;
 134
 135                 ret = bq24735_write_word(charger->client,
 136                                          BQ24735_CHARGE_VOLTAGE, value);
 137                 if (ret < 0) {
 138                         dev_err(&charger->client->dev,
 139                                 "Failed to write charger voltage : %d\n",
 140                                 ret);
 141                         return ret;
 142                 }
 143         }
 144
 145         if (pdata->input_current) {
 146                 value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;
 147
 148                 ret = bq24735_write_word(charger->client,
 149                                          BQ24735_INPUT_CURRENT, value);
 150                 if (ret < 0) {
 151                         dev_err(&charger->client->dev,
 152                                 "Failed to write input current : %d\n",
 153                                 ret);
 154                         return ret;
 155                 }
 156         }
 157
 158         return 0;
 159 }
 160
 161 static inline int bq24735_enable_charging(struct bq24735 *charger)
 162 {
 163         int ret;
 164
 165         if (charger->pdata->ext_control)
 166                 return 0;
 167
 168         ret = bq24735_config_charger(charger);
 169         if (ret)
 170                 return ret;
 171
 172         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 173                                    BQ24735_CHG_OPT_CHARGE_DISABLE, 0);
 174 }
 175
 176 static inline int bq24735_disable_charging(struct bq24735 *charger)
 177 {
 178         if (charger->pdata->ext_control)
 179                 return 0;
 180
 181         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 182                                    BQ24735_CHG_OPT_CHARGE_DISABLE,
 183                                    BQ24735_CHG_OPT_CHARGE_DISABLE);
 184 }
 185
 186 static bool bq24735_charger_is_present(struct bq24735 *charger)
 187 {
 188         if (charger->status_gpio) {
 189                 return !gpiod_get_value_cansleep(charger->status_gpio);
 190         } else {
 191                 int ac = 0;
 192
 193                 ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 194                 if (ac < 0) {
 195                         dev_dbg(&charger->client->dev,
 196                                 "Failed to read charger options : %d\n",
 197                                 ac);
 198                         return false;
 199                 }
 200                 return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
 201         }
 202
 203         return false;
 204 }
 205
 206 static int bq24735_charger_is_charging(struct bq24735 *charger)
 207 {
 208         int ret;
 209
 210         if (!bq24735_charger_is_present(charger))
 211                 return 0;
 212
 213         ret  = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 214         if (ret < 0)
 215                 return ret;
 216
 217         return !(ret & BQ24735_CHG_OPT_CHARGE_DISABLE);
 218 }
 219
 220 static void bq24735_update(struct bq24735 *charger)
 221 {
 222         mutex_lock(&charger->lock);
 223
 224         if (charger->charging && bq24735_charger_is_present(charger))
 225                 bq24735_enable_charging(charger);
 226         else
 227                 bq24735_disable_charging(charger);
 228
 229         mutex_unlock(&charger->lock);
 230
 231         power_supply_changed(charger->charger);
 232 }
 233
 234 static irqreturn_t bq24735_charger_isr(int irq, void *devid)
 235 {
 236         struct power_supply *psy = devid;
 237         struct bq24735 *charger = to_bq24735(psy);
 238
 239         bq24735_update(charger);
 240
 241         return IRQ_HANDLED;
 242 }
 243
 244 static void bq24735_poll(struct work_struct *work)
 245 {
 246         struct bq24735 *charger = container_of(work, struct bq24735, poll.work);
 247
 248         bq24735_update(charger);
 249
 250         schedule_delayed_work(&charger->poll,
 251                               msecs_to_jiffies(charger->poll_interval));
 252 }
 253
 254 static int bq24735_charger_get_property(struct power_supply *psy,
 255                                         enum power_supply_property psp,
 256                                         union power_supply_propval *val)
 257 {
 258         struct bq24735 *charger = to_bq24735(psy);
 259
 260         switch (psp) {
 261         case POWER_SUPPLY_PROP_ONLINE:
 262                 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
 263                 break;
 264         case POWER_SUPPLY_PROP_STATUS:
 265                 switch (bq24735_charger_is_charging(charger)) {
 266                 case 1:
 267                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 268                         break;
 269                 case 0:
 270                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 271                         break;
 272                 default:
 273                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 274                         break;
 275                 }
 276                 break;
 277         default:
 278                 return -EINVAL;
 279         }
 280
 281         return 0;
 282 }
 283
 284 static int bq24735_charger_set_property(struct power_supply *psy,
 285                                         enum power_supply_property psp,
 286                                         const union power_supply_propval *val)
 287 {
 288         struct bq24735 *charger = to_bq24735(psy);
 289         int ret;
 290
 291         switch (psp) {
 292         case POWER_SUPPLY_PROP_STATUS:
 293                 switch (val->intval) {
 294                 case POWER_SUPPLY_STATUS_CHARGING:
 295                         mutex_lock(&charger->lock);
 296                         charger->charging = true;
 297                         ret = bq24735_enable_charging(charger);
 298                         mutex_unlock(&charger->lock);
 299                         if (ret)
 300                                 return ret;
 301                         break;
 302                 case POWER_SUPPLY_STATUS_DISCHARGING:
 303                 case POWER_SUPPLY_STATUS_NOT_CHARGING:
 304                         mutex_lock(&charger->lock);
 305                         charger->charging = false;
 306                         ret = bq24735_disable_charging(charger);
 307                         mutex_unlock(&charger->lock);
 308                         if (ret)
 309                                 return ret;
 310                         break;
 311                 default:
 312                         return -EINVAL;
 313                 }
 314                 power_supply_changed(psy);
 315                 break;
 316         default:
 317                 return -EPERM;
 318         }
 319
 320         return 0;
 321 }
 322
 323 static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 324 {
 325         struct bq24735_platform *pdata;
 326         struct device_node *np = client->dev.of_node;
 327         u32 val;
 328         int ret;
 329
 330         pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
 331         if (!pdata) {
 332                 dev_err(&client->dev,
 333                         "Memory alloc for bq24735 pdata failed\n");
 334                 return NULL;
 335         }
 336
 337         ret = of_property_read_u32(np, "ti,charge-current", &val);
 338         if (!ret)
 339                 pdata->charge_current = val;
 340
 341         ret = of_property_read_u32(np, "ti,charge-voltage", &val);
 342         if (!ret)
 343                 pdata->charge_voltage = val;
 344
 345         ret = of_property_read_u32(np, "ti,input-current", &val);
 346         if (!ret)
 347                 pdata->input_current = val;
 348
 349         pdata->ext_control = of_property_read_bool(np, "ti,external-control");
 350
 351         return pdata;
 352 }
 353
 354 static int bq24735_charger_probe(struct i2c_client *client,
 355                                  const struct i2c_device_id *id)
 356 {
 357         int ret;
 358         struct bq24735 *charger;
 359         struct power_supply_desc *supply_desc;
 360         struct power_supply_config psy_cfg = {};
 361         char *name;
 362
 363         charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
 364         if (!charger)
 365                 return -ENOMEM;
 366
 367         mutex_init(&charger->lock);
 368         charger->charging = true;
 369         charger->pdata = client->dev.platform_data;
 370
 371         if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
 372                 charger->pdata = bq24735_parse_dt_data(client);
 373
 374         if (!charger->pdata) {
 375                 dev_err(&client->dev, "no platform data provided\n");
 376                 return -EINVAL;
 377         }
 378
 379         name = (char *)charger->pdata->name;
 380         if (!name) {
 381                 name = devm_kasprintf(&client->dev, GFP_KERNEL,
 382                                       "bq24735@%s",
 383                                       dev_name(&client->dev));
 384                 if (!name) {
 385                         dev_err(&client->dev, "Failed to alloc device name\n");
 386                         return -ENOMEM;
 387                 }
 388         }
 389
 390         charger->client = client;
 391
 392         supply_desc = &charger->charger_desc;
 393
 394         supply_desc->name = name;
 395         supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
 396         supply_desc->properties = bq24735_charger_properties;
 397         supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
 398         supply_desc->get_property = bq24735_charger_get_property;
 399         supply_desc->set_property = bq24735_charger_set_property;
 400         supply_desc->property_is_writeable =
 401                                 bq24735_charger_property_is_writeable;
 402
 403         psy_cfg.supplied_to = charger->pdata->supplied_to;
 404         psy_cfg.num_supplicants = charger->pdata->num_supplicants;
 405         psy_cfg.of_node = client->dev.of_node;
 406         psy_cfg.drv_data = charger;
 407
 408         i2c_set_clientdata(client, charger);
 409
 410         charger->status_gpio = devm_gpiod_get_optional(&client->dev,
 411                                                        "ti,ac-detect",
 412                                                        GPIOD_IN);
 413         if (IS_ERR(charger->status_gpio)) {
 414                 ret = PTR_ERR(charger->status_gpio);
 415                 dev_err(&client->dev, "Getting gpio failed: %d\n", ret);
 416                 return ret;
 417         }
 418
 419         if (bq24735_charger_is_present(charger)) {
 420                 ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
 421                 if (ret < 0) {
 422                         dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
 423                                 ret);
 424                         return ret;
 425                 } else if (ret != 0x0040) {
 426                         dev_err(&client->dev,
 427                                 "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
 428                         return -ENODEV;
 429                 }
 430
 431                 ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
 432                 if (ret < 0) {
 433                         dev_err(&client->dev, "Failed to read device id : %d\n", ret);
 434                         return ret;
 435                 } else if (ret != 0x000B) {
 436                         dev_err(&client->dev,
 437                                 "device id mismatch. 0x000b != 0x%04x\n", ret);
 438                         return -ENODEV;
 439                 }
 440
 441                 ret = bq24735_enable_charging(charger);
 442                 if (ret < 0) {
 443                         dev_err(&client->dev, "Failed to enable charging\n");
 444                         return ret;
 445                 }
 446         }
 447
 448         charger->charger = devm_power_supply_register(&client->dev, supply_desc,
 449                                                       &psy_cfg);
 450         if (IS_ERR(charger->charger)) {
 451                 ret = PTR_ERR(charger->charger);
 452                 dev_err(&client->dev, "Failed to register power supply: %d\n",
 453                         ret);
 454                 return ret;
 455         }
 456
 457         if (client->irq) {
 458                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 459                                                 NULL, bq24735_charger_isr,
 460                                                 IRQF_TRIGGER_RISING |
 461                                                 IRQF_TRIGGER_FALLING |
 462                                                 IRQF_ONESHOT,
 463                                                 supply_desc->name,
 464                                                 charger->charger);
 465                 if (ret) {
 466                         dev_err(&client->dev,
 467                                 "Unable to register IRQ %d err %d\n",
 468                                 client->irq, ret);
 469                         return ret;
 470                 }
 471         } else {
 472                 ret = device_property_read_u32(&client->dev, "poll-interval",
 473                                                &charger->poll_interval);
 474                 if (ret)
 475                         return 0;
 476                 if (!charger->poll_interval)
 477                         return 0;
 478
 479                 INIT_DELAYED_WORK(&charger->poll, bq24735_poll);
 480                 schedule_delayed_work(&charger->poll,
 481                                       msecs_to_jiffies(charger->poll_interval));
 482         }
 483
 484         return 0;
 485 }
 486
 487 static int bq24735_charger_remove(struct i2c_client *client)
 488 {
 489         struct bq24735 *charger = i2c_get_clientdata(client);
 490
 491         if (charger->poll_interval)
 492                 cancel_delayed_work_sync(&charger->poll);
 493
 494         return 0;
 495 }
 496
 497 static const struct i2c_device_id bq24735_charger_id[] = {
 498         { "bq24735-charger", 0 },
 499         {}
 500 };
 501 MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
 502
 503 static const struct of_device_id bq24735_match_ids[] = {
 504         { .compatible = "ti,bq24735", },
 505         { /* end */ }
 506 };
 507 MODULE_DEVICE_TABLE(of, bq24735_match_ids);
 508
 509 static struct i2c_driver bq24735_charger_driver = {
 510         .driver = {
 511                 .name = "bq24735-charger",
 512                 .of_match_table = bq24735_match_ids,
 513         },
 514         .probe = bq24735_charger_probe,
 515         .remove = bq24735_charger_remove,
 516         .id_table = bq24735_charger_id,
 517 };
 518
 519 module_i2c_driver(bq24735_charger_driver);
 520
 521 MODULE_DESCRIPTION("bq24735 battery charging driver");
 522 MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
 523 MODULE_LICENSE("GPL v2");