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