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/i2c.h>
  22 #include <linux/init.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/of.h>
  27 #include <linux/gpio/consumer.h>
  28 #include <linux/power_supply.h>
  29 #include <linux/slab.h>
  30
  31 #include <linux/power/bq24735-charger.h>
  32
  33 #define BQ24735_CHG_OPT                 0x12
  34 #define BQ24735_CHG_OPT_CHARGE_DISABLE  (1 << 0)
  35 #define BQ24735_CHG_OPT_AC_PRESENT      (1 << 4)
  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 struct bq24735 {
  46         struct power_supply             *charger;
  47         struct power_supply_desc        charger_desc;
  48         struct i2c_client               *client;
  49         struct bq24735_platform         *pdata;
  50         struct mutex                    lock;
  51         struct gpio_desc                *status_gpio;
  52         struct delayed_work             poll;
  53         u32                             poll_interval;
  54         bool                            charging;
  55 };
  56
  57 static inline struct bq24735 *to_bq24735(struct power_supply *psy)
  58 {
  59         return power_supply_get_drvdata(psy);
  60 }
  61
  62 static enum power_supply_property bq24735_charger_properties[] = {
  63         POWER_SUPPLY_PROP_STATUS,
  64         POWER_SUPPLY_PROP_ONLINE,
  65 };
  66
  67 static int bq24735_charger_property_is_writeable(struct power_supply *psy,
  68                                                  enum power_supply_property psp)
  69 {
  70         switch (psp) {
  71         case POWER_SUPPLY_PROP_STATUS:
  72                 return 1;
  73         default:
  74                 break;
  75         }
  76
  77         return 0;
  78 }
  79
  80 static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
  81                                      u16 value)
  82 {
  83         return i2c_smbus_write_word_data(client, reg, value);
  84 }
  85
  86 static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
  87 {
  88         return i2c_smbus_read_word_data(client, reg);
  89 }
  90
  91 static int bq24735_update_word(struct i2c_client *client, u8 reg,
  92                                u16 mask, u16 value)
  93 {
  94         unsigned int tmp;
  95         int ret;
  96
  97         ret = bq24735_read_word(client, reg);
  98         if (ret < 0)
  99                 return ret;
 100
 101         tmp = ret & ~mask;
 102         tmp |= value & mask;
 103
 104         return bq24735_write_word(client, reg, tmp);
 105 }
 106
 107 static int bq24735_config_charger(struct bq24735 *charger)
 108 {
 109         struct bq24735_platform *pdata = charger->pdata;
 110         int ret;
 111         u16 value;
 112
 113         if (pdata->ext_control)
 114                 return 0;
 115
 116         if (pdata->charge_current) {
 117                 value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;
 118
 119                 ret = bq24735_write_word(charger->client,
 120                                          BQ24735_CHARGE_CURRENT, value);
 121                 if (ret < 0) {
 122                         dev_err(&charger->client->dev,
 123                                 "Failed to write charger current : %d\n",
 124                                 ret);
 125                         return ret;
 126                 }
 127         }
 128
 129         if (pdata->charge_voltage) {
 130                 value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;
 131
 132                 ret = bq24735_write_word(charger->client,
 133                                          BQ24735_CHARGE_VOLTAGE, value);
 134                 if (ret < 0) {
 135                         dev_err(&charger->client->dev,
 136                                 "Failed to write charger voltage : %d\n",
 137                                 ret);
 138                         return ret;
 139                 }
 140         }
 141
 142         if (pdata->input_current) {
 143                 value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;
 144
 145                 ret = bq24735_write_word(charger->client,
 146                                          BQ24735_INPUT_CURRENT, value);
 147                 if (ret < 0) {
 148                         dev_err(&charger->client->dev,
 149                                 "Failed to write input current : %d\n",
 150                                 ret);
 151                         return ret;
 152                 }
 153         }
 154
 155         return 0;
 156 }
 157
 158 static inline int bq24735_enable_charging(struct bq24735 *charger)
 159 {
 160         int ret;
 161
 162         if (charger->pdata->ext_control)
 163                 return 0;
 164
 165         ret = bq24735_config_charger(charger);
 166         if (ret)
 167                 return ret;
 168
 169         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 170                                    BQ24735_CHG_OPT_CHARGE_DISABLE, 0);
 171 }
 172
 173 static inline int bq24735_disable_charging(struct bq24735 *charger)
 174 {
 175         if (charger->pdata->ext_control)
 176                 return 0;
 177
 178         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 179                                    BQ24735_CHG_OPT_CHARGE_DISABLE,
 180                                    BQ24735_CHG_OPT_CHARGE_DISABLE);
 181 }
 182
 183 static bool bq24735_charger_is_present(struct bq24735 *charger)
 184 {
 185         if (charger->status_gpio) {
 186                 return !gpiod_get_value_cansleep(charger->status_gpio);
 187         } else {
 188                 int ac = 0;
 189
 190                 ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 191                 if (ac < 0) {
 192                         dev_dbg(&charger->client->dev,
 193                                 "Failed to read charger options : %d\n",
 194                                 ac);
 195                         return false;
 196                 }
 197                 return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
 198         }
 199
 200         return false;
 201 }
 202
 203 static int bq24735_charger_is_charging(struct bq24735 *charger)
 204 {
 205         int ret;
 206
 207         if (!bq24735_charger_is_present(charger))
 208                 return 0;
 209
 210         ret  = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 211         if (ret < 0)
 212                 return ret;
 213
 214         return !(ret & BQ24735_CHG_OPT_CHARGE_DISABLE);
 215 }
 216
 217 static void bq24735_update(struct bq24735 *charger)
 218 {
 219         mutex_lock(&charger->lock);
 220
 221         if (charger->charging && bq24735_charger_is_present(charger))
 222                 bq24735_enable_charging(charger);
 223         else
 224                 bq24735_disable_charging(charger);
 225
 226         mutex_unlock(&charger->lock);
 227
 228         power_supply_changed(charger->charger);
 229 }
 230
 231 static irqreturn_t bq24735_charger_isr(int irq, void *devid)
 232 {
 233         struct power_supply *psy = devid;
 234         struct bq24735 *charger = to_bq24735(psy);
 235
 236         bq24735_update(charger);
 237
 238         return IRQ_HANDLED;
 239 }
 240
 241 static void bq24735_poll(struct work_struct *work)
 242 {
 243         struct bq24735 *charger = container_of(work, struct bq24735, poll.work);
 244
 245         bq24735_update(charger);
 246
 247         schedule_delayed_work(&charger->poll,
 248                               msecs_to_jiffies(charger->poll_interval));
 249 }
 250
 251 static int bq24735_charger_get_property(struct power_supply *psy,
 252                                         enum power_supply_property psp,
 253                                         union power_supply_propval *val)
 254 {
 255         struct bq24735 *charger = to_bq24735(psy);
 256
 257         switch (psp) {
 258         case POWER_SUPPLY_PROP_ONLINE:
 259                 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
 260                 break;
 261         case POWER_SUPPLY_PROP_STATUS:
 262                 switch (bq24735_charger_is_charging(charger)) {
 263                 case 1:
 264                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 265                         break;
 266                 case 0:
 267                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 268                         break;
 269                 default:
 270                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 271                         break;
 272                 }
 273                 break;
 274         default:
 275                 return -EINVAL;
 276         }
 277
 278         return 0;
 279 }
 280
 281 static int bq24735_charger_set_property(struct power_supply *psy,
 282                                         enum power_supply_property psp,
 283                                         const union power_supply_propval *val)
 284 {
 285         struct bq24735 *charger = to_bq24735(psy);
 286         int ret;
 287
 288         switch (psp) {
 289         case POWER_SUPPLY_PROP_STATUS:
 290                 switch (val->intval) {
 291                 case POWER_SUPPLY_STATUS_CHARGING:
 292                         mutex_lock(&charger->lock);
 293                         charger->charging = true;
 294                         ret = bq24735_enable_charging(charger);
 295                         mutex_unlock(&charger->lock);
 296                         if (ret)
 297                                 return ret;
 298                         break;
 299                 case POWER_SUPPLY_STATUS_DISCHARGING:
 300                 case POWER_SUPPLY_STATUS_NOT_CHARGING:
 301                         mutex_lock(&charger->lock);
 302                         charger->charging = false;
 303                         ret = bq24735_disable_charging(charger);
 304                         mutex_unlock(&charger->lock);
 305                         if (ret)
 306                                 return ret;
 307                         break;
 308                 default:
 309                         return -EINVAL;
 310                 }
 311                 power_supply_changed(psy);
 312                 break;
 313         default:
 314                 return -EPERM;
 315         }
 316
 317         return 0;
 318 }
 319
 320 static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 321 {
 322         struct bq24735_platform *pdata;
 323         struct device_node *np = client->dev.of_node;
 324         u32 val;
 325         int ret;
 326
 327         pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
 328         if (!pdata) {
 329                 dev_err(&client->dev,
 330                         "Memory alloc for bq24735 pdata failed\n");
 331                 return NULL;
 332         }
 333
 334         ret = of_property_read_u32(np, "ti,charge-current", &val);
 335         if (!ret)
 336                 pdata->charge_current = val;
 337
 338         ret = of_property_read_u32(np, "ti,charge-voltage", &val);
 339         if (!ret)
 340                 pdata->charge_voltage = val;
 341
 342         ret = of_property_read_u32(np, "ti,input-current", &val);
 343         if (!ret)
 344                 pdata->input_current = val;
 345
 346         pdata->ext_control = of_property_read_bool(np, "ti,external-control");
 347
 348         return pdata;
 349 }
 350
 351 static int bq24735_charger_probe(struct i2c_client *client,
 352                                  const struct i2c_device_id *id)
 353 {
 354         int ret;
 355         struct bq24735 *charger;
 356         struct power_supply_desc *supply_desc;
 357         struct power_supply_config psy_cfg = {};
 358         char *name;
 359
 360         charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL);
 361         if (!charger)
 362                 return -ENOMEM;
 363
 364         mutex_init(&charger->lock);
 365         charger->charging = true;
 366         charger->pdata = client->dev.platform_data;
 367
 368         if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node)
 369                 charger->pdata = bq24735_parse_dt_data(client);
 370
 371         if (!charger->pdata) {
 372                 dev_err(&client->dev, "no platform data provided\n");
 373                 return -EINVAL;
 374         }
 375
 376         name = (char *)charger->pdata->name;
 377         if (!name) {
 378                 name = devm_kasprintf(&client->dev, GFP_KERNEL,
 379                                       "bq24735@%s",
 380                                       dev_name(&client->dev));
 381                 if (!name) {
 382                         dev_err(&client->dev, "Failed to alloc device name\n");
 383                         return -ENOMEM;
 384                 }
 385         }
 386
 387         charger->client = client;
 388
 389         supply_desc = &charger->charger_desc;
 390
 391         supply_desc->name = name;
 392         supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
 393         supply_desc->properties = bq24735_charger_properties;
 394         supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
 395         supply_desc->get_property = bq24735_charger_get_property;
 396         supply_desc->set_property = bq24735_charger_set_property;
 397         supply_desc->property_is_writeable =
 398                                 bq24735_charger_property_is_writeable;
 399
 400         psy_cfg.supplied_to = charger->pdata->supplied_to;
 401         psy_cfg.num_supplicants = charger->pdata->num_supplicants;
 402         psy_cfg.of_node = client->dev.of_node;
 403         psy_cfg.drv_data = charger;
 404
 405         i2c_set_clientdata(client, charger);
 406
 407         charger->status_gpio = devm_gpiod_get_optional(&client->dev,
 408                                                        "ti,ac-detect",
 409                                                        GPIOD_IN);
 410         if (IS_ERR(charger->status_gpio)) {
 411                 ret = PTR_ERR(charger->status_gpio);
 412                 dev_err(&client->dev, "Getting gpio failed: %d\n", ret);
 413                 return ret;
 414         }
 415
 416         if (bq24735_charger_is_present(charger)) {
 417                 ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
 418                 if (ret < 0) {
 419                         dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
 420                                 ret);
 421                         return ret;
 422                 } else if (ret != 0x0040) {
 423                         dev_err(&client->dev,
 424                                 "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
 425                         return -ENODEV;
 426                 }
 427
 428                 ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
 429                 if (ret < 0) {
 430                         dev_err(&client->dev, "Failed to read device id : %d\n", ret);
 431                         return ret;
 432                 } else if (ret != 0x000B) {
 433                         dev_err(&client->dev,
 434                                 "device id mismatch. 0x000b != 0x%04x\n", ret);
 435                         return -ENODEV;
 436                 }
 437
 438                 ret = bq24735_enable_charging(charger);
 439                 if (ret < 0) {
 440                         dev_err(&client->dev, "Failed to enable charging\n");
 441                         return ret;
 442                 }
 443         }
 444
 445         charger->charger = devm_power_supply_register(&client->dev, supply_desc,
 446                                                       &psy_cfg);
 447         if (IS_ERR(charger->charger)) {
 448                 ret = PTR_ERR(charger->charger);
 449                 dev_err(&client->dev, "Failed to register power supply: %d\n",
 450                         ret);
 451                 return ret;
 452         }
 453
 454         if (client->irq) {
 455                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 456                                                 NULL, bq24735_charger_isr,
 457                                                 IRQF_TRIGGER_RISING |
 458                                                 IRQF_TRIGGER_FALLING |
 459                                                 IRQF_ONESHOT,
 460                                                 supply_desc->name,
 461                                                 charger->charger);
 462                 if (ret) {
 463                         dev_err(&client->dev,
 464                                 "Unable to register IRQ %d err %d\n",
 465                                 client->irq, ret);
 466                         return ret;
 467                 }
 468         } else {
 469                 ret = device_property_read_u32(&client->dev, "poll-interval",
 470                                                &charger->poll_interval);
 471                 if (ret)
 472                         return 0;
 473                 if (!charger->poll_interval)
 474                         return 0;
 475
 476                 INIT_DELAYED_WORK(&charger->poll, bq24735_poll);
 477                 schedule_delayed_work(&charger->poll,
 478                                       msecs_to_jiffies(charger->poll_interval));
 479         }
 480
 481         return 0;
 482 }
 483
 484 static int bq24735_charger_remove(struct i2c_client *client)
 485 {
 486         struct bq24735 *charger = i2c_get_clientdata(client);
 487
 488         if (charger->poll_interval)
 489                 cancel_delayed_work_sync(&charger->poll);
 490
 491         return 0;
 492 }
 493
 494 static const struct i2c_device_id bq24735_charger_id[] = {
 495         { "bq24735-charger", 0 },
 496         {}
 497 };
 498 MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
 499
 500 static const struct of_device_id bq24735_match_ids[] = {
 501         { .compatible = "ti,bq24735", },
 502         { /* end */ }
 503 };
 504 MODULE_DEVICE_TABLE(of, bq24735_match_ids);
 505
 506 static struct i2c_driver bq24735_charger_driver = {
 507         .driver = {
 508                 .name = "bq24735-charger",
 509                 .of_match_table = bq24735_match_ids,
 510         },
 511         .probe = bq24735_charger_probe,
 512         .remove = bq24735_charger_remove,
 513         .id_table = bq24735_charger_id,
 514 };
 515
 516 module_i2c_driver(bq24735_charger_driver);
 517
 518 MODULE_DESCRIPTION("bq24735 battery charging driver");
 519 MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
 520 MODULE_LICENSE("GPL v2");