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         if (charger->pdata->ext_control)
 164                 return 0;
 165
 166         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 167                                    BQ24735_CHG_OPT_CHARGE_DISABLE, 0);
 168 }
 169
 170 static inline int bq24735_disable_charging(struct bq24735 *charger)
 171 {
 172         if (charger->pdata->ext_control)
 173                 return 0;
 174
 175         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 176                                    BQ24735_CHG_OPT_CHARGE_DISABLE,
 177                                    BQ24735_CHG_OPT_CHARGE_DISABLE);
 178 }
 179
 180 static bool bq24735_charger_is_present(struct bq24735 *charger)
 181 {
 182         if (charger->status_gpio) {
 183                 return !gpiod_get_value_cansleep(charger->status_gpio);
 184         } else {
 185                 int ac = 0;
 186
 187                 ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 188                 if (ac < 0) {
 189                         dev_err(&charger->client->dev,
 190                                 "Failed to read charger options : %d\n",
 191                                 ac);
 192                         return false;
 193                 }
 194                 return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
 195         }
 196
 197         return false;
 198 }
 199
 200 static int bq24735_charger_is_charging(struct bq24735 *charger)
 201 {
 202         int ret;
 203
 204         if (!bq24735_charger_is_present(charger))
 205                 return 0;
 206
 207         ret  = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 208         if (ret < 0)
 209                 return ret;
 210
 211         return !(ret & BQ24735_CHG_OPT_CHARGE_DISABLE);
 212 }
 213
 214 static void bq24735_update(struct bq24735 *charger)
 215 {
 216         mutex_lock(&charger->lock);
 217
 218         if (charger->charging && bq24735_charger_is_present(charger))
 219                 bq24735_enable_charging(charger);
 220         else
 221                 bq24735_disable_charging(charger);
 222
 223         mutex_unlock(&charger->lock);
 224
 225         power_supply_changed(charger->charger);
 226 }
 227
 228 static irqreturn_t bq24735_charger_isr(int irq, void *devid)
 229 {
 230         struct power_supply *psy = devid;
 231         struct bq24735 *charger = to_bq24735(psy);
 232
 233         bq24735_update(charger);
 234
 235         return IRQ_HANDLED;
 236 }
 237
 238 static void bq24735_poll(struct work_struct *work)
 239 {
 240         struct bq24735 *charger = container_of(work, struct bq24735, poll.work);
 241
 242         bq24735_update(charger);
 243
 244         schedule_delayed_work(&charger->poll,
 245                               msecs_to_jiffies(charger->poll_interval));
 246 }
 247
 248 static int bq24735_charger_get_property(struct power_supply *psy,
 249                                         enum power_supply_property psp,
 250                                         union power_supply_propval *val)
 251 {
 252         struct bq24735 *charger = to_bq24735(psy);
 253
 254         switch (psp) {
 255         case POWER_SUPPLY_PROP_ONLINE:
 256                 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
 257                 break;
 258         case POWER_SUPPLY_PROP_STATUS:
 259                 switch (bq24735_charger_is_charging(charger)) {
 260                 case 1:
 261                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 262                         break;
 263                 case 0:
 264                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 265                         break;
 266                 default:
 267                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 268                         break;
 269                 }
 270                 break;
 271         default:
 272                 return -EINVAL;
 273         }
 274
 275         return 0;
 276 }
 277
 278 static int bq24735_charger_set_property(struct power_supply *psy,
 279                                         enum power_supply_property psp,
 280                                         const union power_supply_propval *val)
 281 {
 282         struct bq24735 *charger = to_bq24735(psy);
 283         int ret;
 284
 285         switch (psp) {
 286         case POWER_SUPPLY_PROP_STATUS:
 287                 switch (val->intval) {
 288                 case POWER_SUPPLY_STATUS_CHARGING:
 289                         mutex_lock(&charger->lock);
 290                         charger->charging = true;
 291                         ret = bq24735_enable_charging(charger);
 292                         mutex_unlock(&charger->lock);
 293                         if (ret)
 294                                 return ret;
 295                         bq24735_config_charger(charger);
 296                         break;
 297                 case POWER_SUPPLY_STATUS_DISCHARGING:
 298                 case POWER_SUPPLY_STATUS_NOT_CHARGING:
 299                         mutex_lock(&charger->lock);
 300                         charger->charging = false;
 301                         ret = bq24735_disable_charging(charger);
 302                         mutex_unlock(&charger->lock);
 303                         if (ret)
 304                                 return ret;
 305                         break;
 306                 default:
 307                         return -EINVAL;
 308                 }
 309                 power_supply_changed(psy);
 310                 break;
 311         default:
 312                 return -EPERM;
 313         }
 314
 315         return 0;
 316 }
 317
 318 static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 319 {
 320         struct bq24735_platform *pdata;
 321         struct device_node *np = client->dev.of_node;
 322         u32 val;
 323         int ret;
 324
 325         pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
 326         if (!pdata) {
 327                 dev_err(&client->dev,
 328                         "Memory alloc for bq24735 pdata failed\n");
 329                 return NULL;
 330         }
 331
 332         ret = of_property_read_u32(np, "ti,charge-current", &val);
 333         if (!ret)
 334                 pdata->charge_current = val;
 335
 336         ret = of_property_read_u32(np, "ti,charge-voltage", &val);
 337         if (!ret)
 338                 pdata->charge_voltage = val;
 339
 340         ret = of_property_read_u32(np, "ti,input-current", &val);
 341         if (!ret)
 342                 pdata->input_current = val;
 343
 344         pdata->ext_control = of_property_read_bool(np, "ti,external-control");
 345
 346         return pdata;
 347 }
 348
 349 static int bq24735_charger_probe(struct i2c_client *client,
 350                                  const struct i2c_device_id *id)
 351 {
 352         int ret;
 353         struct bq24735 *charger;
 354         struct power_supply_desc *supply_desc;
 355         struct power_supply_config psy_cfg = {};
 356         char *name;
 357
 358         charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
 359         if (!charger)
 360                 return -ENOMEM;
 361
 362         mutex_init(&charger->lock);
 363         charger->charging = true;
 364         charger->pdata = client->dev.platform_data;
 365
 366         if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
 367                 charger->pdata = bq24735_parse_dt_data(client);
 368
 369         if (!charger->pdata) {
 370                 dev_err(&client->dev, "no platform data provided\n");
 371                 return -EINVAL;
 372         }
 373
 374         name = (char *)charger->pdata->name;
 375         if (!name) {
 376                 name = devm_kasprintf(&client->dev, GFP_KERNEL,
 377                                       "bq24735@%s",
 378                                       dev_name(&client->dev));
 379                 if (!name) {
 380                         dev_err(&client->dev, "Failed to alloc device name\n");
 381                         return -ENOMEM;
 382                 }
 383         }
 384
 385         charger->client = client;
 386
 387         supply_desc = &charger->charger_desc;
 388
 389         supply_desc->name = name;
 390         supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
 391         supply_desc->properties = bq24735_charger_properties;
 392         supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
 393         supply_desc->get_property = bq24735_charger_get_property;
 394         supply_desc->set_property = bq24735_charger_set_property;
 395         supply_desc->property_is_writeable =
 396                                 bq24735_charger_property_is_writeable;
 397
 398         psy_cfg.supplied_to = charger->pdata->supplied_to;
 399         psy_cfg.num_supplicants = charger->pdata->num_supplicants;
 400         psy_cfg.of_node = client->dev.of_node;
 401         psy_cfg.drv_data = charger;
 402
 403         i2c_set_clientdata(client, charger);
 404
 405         charger->status_gpio = devm_gpiod_get_optional(&client->dev,
 406                                                        "ti,ac-detect",
 407                                                        GPIOD_IN);
 408         if (IS_ERR(charger->status_gpio)) {
 409                 ret = PTR_ERR(charger->status_gpio);
 410                 dev_err(&client->dev, "Getting gpio failed: %d\n", ret);
 411                 return ret;
 412         }
 413
 414         if (!charger->status_gpio || bq24735_charger_is_present(charger)) {
 415                 ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
 416                 if (ret < 0) {
 417                         dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
 418                                 ret);
 419                         return ret;
 420                 } else if (ret != 0x0040) {
 421                         dev_err(&client->dev,
 422                                 "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
 423                         return -ENODEV;
 424                 }
 425
 426                 ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
 427                 if (ret < 0) {
 428                         dev_err(&client->dev, "Failed to read device id : %d\n", ret);
 429                         return ret;
 430                 } else if (ret != 0x000B) {
 431                         dev_err(&client->dev,
 432                                 "device id mismatch. 0x000b != 0x%04x\n", ret);
 433                         return -ENODEV;
 434                 }
 435         }
 436
 437         ret = bq24735_config_charger(charger);
 438         if (ret < 0) {
 439                 dev_err(&client->dev, "failed in configuring charger");
 440                 return ret;
 441         }
 442
 443         /* check for AC adapter presence */
 444         if (bq24735_charger_is_present(charger)) {
 445                 ret = bq24735_enable_charging(charger);
 446                 if (ret < 0) {
 447                         dev_err(&client->dev, "Failed to enable charging\n");
 448                         return ret;
 449                 }
 450         }
 451
 452         charger->charger = devm_power_supply_register(&client->dev, supply_desc,
 453                                                       &psy_cfg);
 454         if (IS_ERR(charger->charger)) {
 455                 ret = PTR_ERR(charger->charger);
 456                 dev_err(&client->dev, "Failed to register power supply: %d\n",
 457                         ret);
 458                 return ret;
 459         }
 460
 461         if (client->irq) {
 462                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 463                                                 NULL, bq24735_charger_isr,
 464                                                 IRQF_TRIGGER_RISING |
 465                                                 IRQF_TRIGGER_FALLING |
 466                                                 IRQF_ONESHOT,
 467                                                 supply_desc->name,
 468                                                 charger->charger);
 469                 if (ret) {
 470                         dev_err(&client->dev,
 471                                 "Unable to register IRQ %d err %d\n",
 472                                 client->irq, ret);
 473                         return ret;
 474                 }
 475         } else if (charger->status_gpio) {
 476                 ret = device_property_read_u32(&client->dev, "poll-interval",
 477                                                &charger->poll_interval);
 478                 if (ret)
 479                         return 0;
 480                 if (!charger->poll_interval)
 481                         return 0;
 482
 483                 INIT_DELAYED_WORK(&charger->poll, bq24735_poll);
 484                 schedule_delayed_work(&charger->poll,
 485                                       msecs_to_jiffies(charger->poll_interval));
 486         }
 487
 488         return 0;
 489 }
 490
 491 static int bq24735_charger_remove(struct i2c_client *client)
 492 {
 493         struct bq24735 *charger = i2c_get_clientdata(client);
 494
 495         if (charger->poll_interval)
 496                 cancel_delayed_work_sync(&charger->poll);
 497
 498         return 0;
 499 }
 500
 501 static const struct i2c_device_id bq24735_charger_id[] = {
 502         { "bq24735-charger", 0 },
 503         {}
 504 };
 505 MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
 506
 507 static const struct of_device_id bq24735_match_ids[] = {
 508         { .compatible = "ti,bq24735", },
 509         { /* end */ }
 510 };
 511 MODULE_DEVICE_TABLE(of, bq24735_match_ids);
 512
 513 static struct i2c_driver bq24735_charger_driver = {
 514         .driver = {
 515                 .name = "bq24735-charger",
 516                 .of_match_table = bq24735_match_ids,
 517         },
 518         .probe = bq24735_charger_probe,
 519         .remove = bq24735_charger_remove,
 520         .id_table = bq24735_charger_id,
 521 };
 522
 523 module_i2c_driver(bq24735_charger_driver);
 524
 525 MODULE_DESCRIPTION("bq24735 battery charging driver");
 526 MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
 527 MODULE_LICENSE("GPL v2");