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