kernel/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 power_supply_desc        charger_desc;
  49         struct i2c_client               *client;
  50         struct bq24735_platform         *pdata;
  51 };
  52
  53 static inline struct bq24735 *to_bq24735(struct power_supply *psy)
  54 {
  55         return power_supply_get_drvdata(psy);
  56 }
  57
  58 static enum power_supply_property bq24735_charger_properties[] = {
  59         POWER_SUPPLY_PROP_ONLINE,
  60 };
  61
  62 static inline int bq24735_write_word(struct i2c_client *client, u8 reg,
  63                                      u16 value)
  64 {
  65         return i2c_smbus_write_word_data(client, reg, le16_to_cpu(value));
  66 }
  67
  68 static inline int bq24735_read_word(struct i2c_client *client, u8 reg)
  69 {
  70         s32 ret = i2c_smbus_read_word_data(client, reg);
  71
  72         return ret < 0 ? ret : le16_to_cpu(ret);
  73 }
  74
  75 static int bq24735_update_word(struct i2c_client *client, u8 reg,
  76                                u16 mask, u16 value)
  77 {
  78         unsigned int tmp;
  79         int ret;
  80
  81         ret = bq24735_read_word(client, reg);
  82         if (ret < 0)
  83                 return ret;
  84
  85         tmp = ret & ~mask;
  86         tmp |= value & mask;
  87
  88         return bq24735_write_word(client, reg, tmp);
  89 }
  90
  91 static inline int bq24735_enable_charging(struct bq24735 *charger)
  92 {
  93         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
  94                                    BQ24735_CHG_OPT_CHARGE_DISABLE,
  95                                    ~BQ24735_CHG_OPT_CHARGE_DISABLE);
  96 }
  97
  98 static inline int bq24735_disable_charging(struct bq24735 *charger)
  99 {
 100         return bq24735_update_word(charger->client, BQ24735_CHG_OPT,
 101                                    BQ24735_CHG_OPT_CHARGE_DISABLE,
 102                                    BQ24735_CHG_OPT_CHARGE_DISABLE);
 103 }
 104
 105 static int bq24735_config_charger(struct bq24735 *charger)
 106 {
 107         struct bq24735_platform *pdata = charger->pdata;
 108         int ret;
 109         u16 value;
 110
 111         if (pdata->charge_current) {
 112                 value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK;
 113
 114                 ret = bq24735_write_word(charger->client,
 115                                          BQ24735_CHARGE_CURRENT, value);
 116                 if (ret < 0) {
 117                         dev_err(&charger->client->dev,
 118                                 "Failed to write charger current : %d\n",
 119                                 ret);
 120                         return ret;
 121                 }
 122         }
 123
 124         if (pdata->charge_voltage) {
 125                 value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK;
 126
 127                 ret = bq24735_write_word(charger->client,
 128                                          BQ24735_CHARGE_VOLTAGE, value);
 129                 if (ret < 0) {
 130                         dev_err(&charger->client->dev,
 131                                 "Failed to write charger voltage : %d\n",
 132                                 ret);
 133                         return ret;
 134                 }
 135         }
 136
 137         if (pdata->input_current) {
 138                 value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK;
 139
 140                 ret = bq24735_write_word(charger->client,
 141                                          BQ24735_INPUT_CURRENT, value);
 142                 if (ret < 0) {
 143                         dev_err(&charger->client->dev,
 144                                 "Failed to write input current : %d\n",
 145                                 ret);
 146                         return ret;
 147                 }
 148         }
 149
 150         return 0;
 151 }
 152
 153 static bool bq24735_charger_is_present(struct bq24735 *charger)
 154 {
 155         struct bq24735_platform *pdata = charger->pdata;
 156         int ret;
 157
 158         if (pdata->status_gpio_valid) {
 159                 ret = gpio_get_value_cansleep(pdata->status_gpio);
 160                 return ret ^= pdata->status_gpio_active_low == 0;
 161         } else {
 162                 int ac = 0;
 163
 164                 ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT);
 165                 if (ac < 0) {
 166                         dev_err(&charger->client->dev,
 167                                 "Failed to read charger options : %d\n",
 168                                 ac);
 169                         return false;
 170                 }
 171                 return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false;
 172         }
 173
 174         return false;
 175 }
 176
 177 static irqreturn_t bq24735_charger_isr(int irq, void *devid)
 178 {
 179         struct power_supply *psy = devid;
 180         struct bq24735 *charger = to_bq24735(psy);
 181
 182         if (bq24735_charger_is_present(charger))
 183                 bq24735_enable_charging(charger);
 184         else
 185                 bq24735_disable_charging(charger);
 186
 187         power_supply_changed(psy);
 188
 189         return IRQ_HANDLED;
 190 }
 191
 192 static int bq24735_charger_get_property(struct power_supply *psy,
 193                                         enum power_supply_property psp,
 194                                         union power_supply_propval *val)
 195 {
 196         struct bq24735 *charger = to_bq24735(psy);
 197
 198         switch (psp) {
 199         case POWER_SUPPLY_PROP_ONLINE:
 200                 val->intval = bq24735_charger_is_present(charger) ? 1 : 0;
 201                 break;
 202         default:
 203                 return -EINVAL;
 204         }
 205
 206         return 0;
 207 }
 208
 209 static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 210 {
 211         struct bq24735_platform *pdata;
 212         struct device_node *np = client->dev.of_node;
 213         u32 val;
 214         int ret;
 215         enum of_gpio_flags flags;
 216
 217         pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
 218         if (!pdata) {
 219                 dev_err(&client->dev,
 220                         "Memory alloc for bq24735 pdata failed\n");
 221                 return NULL;
 222         }
 223
 224         pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-gpios",
 225                                                      0, &flags);
 226
 227         if (flags & OF_GPIO_ACTIVE_LOW)
 228                 pdata->status_gpio_active_low = 1;
 229
 230         ret = of_property_read_u32(np, "ti,charge-current", &val);
 231         if (!ret)
 232                 pdata->charge_current = val;
 233
 234         ret = of_property_read_u32(np, "ti,charge-voltage", &val);
 235         if (!ret)
 236                 pdata->charge_voltage = val;
 237
 238         ret = of_property_read_u32(np, "ti,input-current", &val);
 239         if (!ret)
 240                 pdata->input_current = val;
 241
 242         return pdata;
 243 }
 244
 245 static int bq24735_charger_probe(struct i2c_client *client,
 246                                  const struct i2c_device_id *id)
 247 {
 248         int ret;
 249         struct bq24735 *charger;
 250         struct power_supply_desc *supply_desc;
 251         struct power_supply_config psy_cfg = {};
 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_desc = &charger->charger_desc;
 281
 282         supply_desc->name = name;
 283         supply_desc->type = POWER_SUPPLY_TYPE_MAINS;
 284         supply_desc->properties = bq24735_charger_properties;
 285         supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties);
 286         supply_desc->get_property = bq24735_charger_get_property;
 287
 288         psy_cfg.supplied_to = charger->pdata->supplied_to;
 289         psy_cfg.num_supplicants = charger->pdata->num_supplicants;
 290         psy_cfg.of_node = client->dev.of_node;
 291         psy_cfg.drv_data = charger;
 292
 293         i2c_set_clientdata(client, charger);
 294
 295         ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
 296         if (ret < 0) {
 297                 dev_err(&client->dev, "Failed to read manufacturer id : %d\n",
 298                         ret);
 299                 goto err_free_name;
 300         } else if (ret != 0x0040) {
 301                 dev_err(&client->dev,
 302                         "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret);
 303                 ret = -ENODEV;
 304                 goto err_free_name;
 305         }
 306
 307         ret = bq24735_read_word(client, BQ24735_DEVICE_ID);
 308         if (ret < 0) {
 309                 dev_err(&client->dev, "Failed to read device id : %d\n", ret);
 310                 goto err_free_name;
 311         } else if (ret != 0x000B) {
 312                 dev_err(&client->dev,
 313                         "device id mismatch. 0x000b != 0x%04x\n", ret);
 314                 ret = -ENODEV;
 315                 goto err_free_name;
 316         }
 317
 318         if (gpio_is_valid(charger->pdata->status_gpio)) {
 319                 ret = devm_gpio_request(&client->dev,
 320                                         charger->pdata->status_gpio,
 321                                         name);
 322                 if (ret) {
 323                         dev_err(&client->dev,
 324                                 "Failed GPIO request for GPIO %d: %d\n",
 325                                 charger->pdata->status_gpio, ret);
 326                 }
 327
 328                 charger->pdata->status_gpio_valid = !ret;
 329         }
 330
 331         ret = bq24735_config_charger(charger);
 332         if (ret < 0) {
 333                 dev_err(&client->dev, "failed in configuring charger");
 334                 goto err_free_name;
 335         }
 336
 337         /* check for AC adapter presence */
 338         if (bq24735_charger_is_present(charger)) {
 339                 ret = bq24735_enable_charging(charger);
 340                 if (ret < 0) {
 341                         dev_err(&client->dev, "Failed to enable charging\n");
 342                         goto err_free_name;
 343                 }
 344         }
 345
 346         charger->charger = power_supply_register(&client->dev, supply_desc,
 347                                                  &psy_cfg);
 348         if (IS_ERR(charger->charger)) {
 349                 ret = PTR_ERR(charger->charger);
 350                 dev_err(&client->dev, "Failed to register power supply: %d\n",
 351                         ret);
 352                 goto err_free_name;
 353         }
 354
 355         if (client->irq) {
 356                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 357                                                 NULL, bq24735_charger_isr,
 358                                                 IRQF_TRIGGER_RISING |
 359                                                 IRQF_TRIGGER_FALLING |
 360                                                 IRQF_ONESHOT,
 361                                                 supply_desc->name,
 362                                                 charger->charger);
 363                 if (ret) {
 364                         dev_err(&client->dev,
 365                                 "Unable to register IRQ %d err %d\n",
 366                                 client->irq, ret);
 367                         goto err_unregister_supply;
 368                 }
 369         }
 370
 371         return 0;
 372 err_unregister_supply:
 373         power_supply_unregister(charger->charger);
 374 err_free_name:
 375         if (name != charger->pdata->name)
 376                 kfree(name);
 377
 378         return ret;
 379 }
 380
 381 static int bq24735_charger_remove(struct i2c_client *client)
 382 {
 383         struct bq24735 *charger = i2c_get_clientdata(client);
 384
 385         if (charger->client->irq)
 386                 devm_free_irq(&charger->client->dev, charger->client->irq,
 387                               &charger->charger);
 388
 389         power_supply_unregister(charger->charger);
 390
 391         if (charger->charger_desc.name != charger->pdata->name)
 392                 kfree(charger->charger_desc.name);
 393
 394         return 0;
 395 }
 396
 397 static const struct i2c_device_id bq24735_charger_id[] = {
 398         { "bq24735-charger", 0 },
 399         {}
 400 };
 401 MODULE_DEVICE_TABLE(i2c, bq24735_charger_id);
 402
 403 static const struct of_device_id bq24735_match_ids[] = {
 404         { .compatible = "ti,bq24735", },
 405         { /* end */ }
 406 };
 407 MODULE_DEVICE_TABLE(of, bq24735_match_ids);
 408
 409 static struct i2c_driver bq24735_charger_driver = {
 410         .driver = {
 411                 .name = "bq24735-charger",
 412                 .owner = THIS_MODULE,
 413                 .of_match_table = bq24735_match_ids,
 414         },
 415         .probe = bq24735_charger_probe,
 416         .remove = bq24735_charger_remove,
 417         .id_table = bq24735_charger_id,
 418 };
 419
 420 module_i2c_driver(bq24735_charger_driver);
 421
 422 MODULE_DESCRIPTION("bq24735 battery charging driver");
 423 MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>");
 424 MODULE_LICENSE("GPL v2");