drivers/regulator/tps65023-regulator.c

   1 /*
   2  * tps65023-regulator.c
   3  *
   4  * Supports TPS65023 Regulator
   5  *
   6  * Copyright (C) 2009 Texas Instrument Incorporated - http://www.ti.com/
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation version 2.
  11  *
  12  * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
  13  * whether express or implied; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/err.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/regulator/driver.h>
  24 #include <linux/regulator/machine.h>
  25 #include <linux/i2c.h>
  26 #include <linux/delay.h>
  27 #include <linux/slab.h>
  28
  29 /* Register definitions */
  30 #define TPS65023_REG_VERSION            0
  31 #define TPS65023_REG_PGOODZ             1
  32 #define TPS65023_REG_MASK               2
  33 #define TPS65023_REG_REG_CTRL           3
  34 #define TPS65023_REG_CON_CTRL           4
  35 #define TPS65023_REG_CON_CTRL2          5
  36 #define TPS65023_REG_DEF_CORE           6
  37 #define TPS65023_REG_DEFSLEW            7
  38 #define TPS65023_REG_LDO_CTRL           8
  39
  40 /* PGOODZ bitfields */
  41 #define TPS65023_PGOODZ_PWRFAILZ        BIT(7)
  42 #define TPS65023_PGOODZ_LOWBATTZ        BIT(6)
  43 #define TPS65023_PGOODZ_VDCDC1          BIT(5)
  44 #define TPS65023_PGOODZ_VDCDC2          BIT(4)
  45 #define TPS65023_PGOODZ_VDCDC3          BIT(3)
  46 #define TPS65023_PGOODZ_LDO2            BIT(2)
  47 #define TPS65023_PGOODZ_LDO1            BIT(1)
  48
  49 /* MASK bitfields */
  50 #define TPS65023_MASK_PWRFAILZ          BIT(7)
  51 #define TPS65023_MASK_LOWBATTZ          BIT(6)
  52 #define TPS65023_MASK_VDCDC1            BIT(5)
  53 #define TPS65023_MASK_VDCDC2            BIT(4)
  54 #define TPS65023_MASK_VDCDC3            BIT(3)
  55 #define TPS65023_MASK_LDO2              BIT(2)
  56 #define TPS65023_MASK_LDO1              BIT(1)
  57
  58 /* REG_CTRL bitfields */
  59 #define TPS65023_REG_CTRL_VDCDC1_EN     BIT(5)
  60 #define TPS65023_REG_CTRL_VDCDC2_EN     BIT(4)
  61 #define TPS65023_REG_CTRL_VDCDC3_EN     BIT(3)
  62 #define TPS65023_REG_CTRL_LDO2_EN       BIT(2)
  63 #define TPS65023_REG_CTRL_LDO1_EN       BIT(1)
  64
  65 /* LDO_CTRL bitfields */
  66 #define TPS65023_LDO_CTRL_LDOx_SHIFT(ldo_id)    ((ldo_id)*4)
  67 #define TPS65023_LDO_CTRL_LDOx_MASK(ldo_id)     (0xF0 >> ((ldo_id)*4))
  68
  69 /* Number of step-down converters available */
  70 #define TPS65023_NUM_DCDC               3
  71 /* Number of LDO voltage regulators  available */
  72 #define TPS65023_NUM_LDO                2
  73 /* Number of total regulators available */
  74 #define TPS65023_NUM_REGULATOR  (TPS65023_NUM_DCDC + TPS65023_NUM_LDO)
  75
  76 /* DCDCs */
  77 #define TPS65023_DCDC_1                 0
  78 #define TPS65023_DCDC_2                 1
  79 #define TPS65023_DCDC_3                 2
  80 /* LDOs */
  81 #define TPS65023_LDO_1                  3
  82 #define TPS65023_LDO_2                  4
  83
  84 #define TPS65023_MAX_REG_ID             TPS65023_LDO_2
  85
  86 /* Supported voltage values for regulators */
  87 static const u16 VDCDC1_VSEL_table[] = {
  88         800, 825, 850, 875,
  89         900, 925, 950, 975,
  90         1000, 1025, 1050, 1075,
  91         1100, 1125, 1150, 1175,
  92         1200, 1225, 1250, 1275,
  93         1300, 1325, 1350, 1375,
  94         1400, 1425, 1450, 1475,
  95         1500, 1525, 1550, 1600,
  96 };
  97
  98 static const u16 LDO1_VSEL_table[] = {
  99         1000, 1100, 1300, 1800,
 100         2200, 2600, 2800, 3150,
 101 };
 102
 103 static const u16 LDO2_VSEL_table[] = {
 104         1050, 1200, 1300, 1800,
 105         2500, 2800, 3000, 3300,
 106 };
 107
 108 static unsigned int num_voltages[] = {ARRAY_SIZE(VDCDC1_VSEL_table),
 109                                 0, 0, ARRAY_SIZE(LDO1_VSEL_table),
 110                                 ARRAY_SIZE(LDO2_VSEL_table)};
 111
 112 /* Regulator specific details */
 113 struct tps_info {
 114         const char *name;
 115         unsigned min_uV;
 116         unsigned max_uV;
 117         bool fixed;
 118         u8 table_len;
 119         const u16 *table;
 120 };
 121
 122 /* PMIC details */
 123 struct tps_pmic {
 124         struct regulator_desc desc[TPS65023_NUM_REGULATOR];
 125         struct i2c_client *client;
 126         struct regulator_dev *rdev[TPS65023_NUM_REGULATOR];
 127         const struct tps_info *info[TPS65023_NUM_REGULATOR];
 128         struct mutex io_lock;
 129 };
 130
 131 static inline int tps_65023_read(struct tps_pmic *tps, u8 reg)
 132 {
 133         return i2c_smbus_read_byte_data(tps->client, reg);
 134 }
 135
 136 static inline int tps_65023_write(struct tps_pmic *tps, u8 reg, u8 val)
 137 {
 138         return i2c_smbus_write_byte_data(tps->client, reg, val);
 139 }
 140
 141 static int tps_65023_set_bits(struct tps_pmic *tps, u8 reg, u8 mask)
 142 {
 143         int err, data;
 144
 145         mutex_lock(&tps->io_lock);
 146
 147         data = tps_65023_read(tps, reg);
 148         if (data < 0) {
 149                 dev_err(&tps->client->dev, "Read from reg 0x%x failed\n", reg);
 150                 err = data;
 151                 goto out;
 152         }
 153
 154         data |= mask;
 155         err = tps_65023_write(tps, reg, data);
 156         if (err)
 157                 dev_err(&tps->client->dev, "Write for reg 0x%x failed\n", reg);
 158
 159 out:
 160         mutex_unlock(&tps->io_lock);
 161         return err;
 162 }
 163
 164 static int tps_65023_clear_bits(struct tps_pmic *tps, u8 reg, u8 mask)
 165 {
 166         int err, data;
 167
 168         mutex_lock(&tps->io_lock);
 169
 170         data = tps_65023_read(tps, reg);
 171         if (data < 0) {
 172                 dev_err(&tps->client->dev, "Read from reg 0x%x failed\n", reg);
 173                 err = data;
 174                 goto out;
 175         }
 176
 177         data &= ~mask;
 178
 179         err = tps_65023_write(tps, reg, data);
 180         if (err)
 181                 dev_err(&tps->client->dev, "Write for reg 0x%x failed\n", reg);
 182
 183 out:
 184         mutex_unlock(&tps->io_lock);
 185         return err;
 186
 187 }
 188
 189 static int tps_65023_reg_read(struct tps_pmic *tps, u8 reg)
 190 {
 191         int data;
 192
 193         mutex_lock(&tps->io_lock);
 194
 195         data = tps_65023_read(tps, reg);
 196         if (data < 0)
 197                 dev_err(&tps->client->dev, "Read from reg 0x%x failed\n", reg);
 198
 199         mutex_unlock(&tps->io_lock);
 200         return data;
 201 }
 202
 203 static int tps_65023_reg_write(struct tps_pmic *tps, u8 reg, u8 val)
 204 {
 205         int err;
 206
 207         mutex_lock(&tps->io_lock);
 208
 209         err = tps_65023_write(tps, reg, val);
 210         if (err < 0)
 211                 dev_err(&tps->client->dev, "Write for reg 0x%x failed\n", reg);
 212
 213         mutex_unlock(&tps->io_lock);
 214         return err;
 215 }
 216
 217 static int tps65023_dcdc_is_enabled(struct regulator_dev *dev)
 218 {
 219         struct tps_pmic *tps = rdev_get_drvdata(dev);
 220         int data, dcdc = rdev_get_id(dev);
 221         u8 shift;
 222
 223         if (dcdc < TPS65023_DCDC_1 || dcdc > TPS65023_DCDC_3)
 224                 return -EINVAL;
 225
 226         shift = TPS65023_NUM_REGULATOR - dcdc;
 227         data = tps_65023_reg_read(tps, TPS65023_REG_REG_CTRL);
 228
 229         if (data < 0)
 230                 return data;
 231         else
 232                 return (data & 1<<shift) ? 1 : 0;
 233 }
 234
 235 static int tps65023_ldo_is_enabled(struct regulator_dev *dev)
 236 {
 237         struct tps_pmic *tps = rdev_get_drvdata(dev);
 238         int data, ldo = rdev_get_id(dev);
 239         u8 shift;
 240
 241         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 242                 return -EINVAL;
 243
 244         shift = (ldo == TPS65023_LDO_1 ? 1 : 2);
 245         data = tps_65023_reg_read(tps, TPS65023_REG_REG_CTRL);
 246
 247         if (data < 0)
 248                 return data;
 249         else
 250                 return (data & 1<<shift) ? 1 : 0;
 251 }
 252
 253 static int tps65023_dcdc_enable(struct regulator_dev *dev)
 254 {
 255         struct tps_pmic *tps = rdev_get_drvdata(dev);
 256         int dcdc = rdev_get_id(dev);
 257         u8 shift;
 258
 259         if (dcdc < TPS65023_DCDC_1 || dcdc > TPS65023_DCDC_3)
 260                 return -EINVAL;
 261
 262         shift = TPS65023_NUM_REGULATOR - dcdc;
 263         return tps_65023_set_bits(tps, TPS65023_REG_REG_CTRL, 1 << shift);
 264 }
 265
 266 static int tps65023_dcdc_disable(struct regulator_dev *dev)
 267 {
 268         struct tps_pmic *tps = rdev_get_drvdata(dev);
 269         int dcdc = rdev_get_id(dev);
 270         u8 shift;
 271
 272         if (dcdc < TPS65023_DCDC_1 || dcdc > TPS65023_DCDC_3)
 273                 return -EINVAL;
 274
 275         shift = TPS65023_NUM_REGULATOR - dcdc;
 276         return tps_65023_clear_bits(tps, TPS65023_REG_REG_CTRL, 1 << shift);
 277 }
 278
 279 static int tps65023_ldo_enable(struct regulator_dev *dev)
 280 {
 281         struct tps_pmic *tps = rdev_get_drvdata(dev);
 282         int ldo = rdev_get_id(dev);
 283         u8 shift;
 284
 285         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 286                 return -EINVAL;
 287
 288         shift = (ldo == TPS65023_LDO_1 ? 1 : 2);
 289         return tps_65023_set_bits(tps, TPS65023_REG_REG_CTRL, 1 << shift);
 290 }
 291
 292 static int tps65023_ldo_disable(struct regulator_dev *dev)
 293 {
 294         struct tps_pmic *tps = rdev_get_drvdata(dev);
 295         int ldo = rdev_get_id(dev);
 296         u8 shift;
 297
 298         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 299                 return -EINVAL;
 300
 301         shift = (ldo == TPS65023_LDO_1 ? 1 : 2);
 302         return tps_65023_clear_bits(tps, TPS65023_REG_REG_CTRL, 1 << shift);
 303 }
 304
 305 static int tps65023_dcdc_get_voltage(struct regulator_dev *dev)
 306 {
 307         struct tps_pmic *tps = rdev_get_drvdata(dev);
 308         int data, dcdc = rdev_get_id(dev);
 309
 310         if (dcdc < TPS65023_DCDC_1 || dcdc > TPS65023_DCDC_3)
 311                 return -EINVAL;
 312
 313         if (dcdc == TPS65023_DCDC_1) {
 314                 data = tps_65023_reg_read(tps, TPS65023_REG_DEF_CORE);
 315                 if (data < 0)
 316                         return data;
 317                 data &= (tps->info[dcdc]->table_len - 1);
 318                 return tps->info[dcdc]->table[data] * 1000;
 319         } else
 320                 return tps->info[dcdc]->min_uV;
 321 }
 322
 323 static int tps65023_dcdc_set_voltage(struct regulator_dev *dev,
 324                                 int min_uV, int max_uV)
 325 {
 326         struct tps_pmic *tps = rdev_get_drvdata(dev);
 327         int dcdc = rdev_get_id(dev);
 328         int vsel;
 329
 330         if (dcdc != TPS65023_DCDC_1)
 331                 return -EINVAL;
 332
 333         if (min_uV < tps->info[dcdc]->min_uV
 334                         || min_uV > tps->info[dcdc]->max_uV)
 335                 return -EINVAL;
 336         if (max_uV < tps->info[dcdc]->min_uV
 337                         || max_uV > tps->info[dcdc]->max_uV)
 338                 return -EINVAL;
 339
 340         for (vsel = 0; vsel < tps->info[dcdc]->table_len; vsel++) {
 341                 int mV = tps->info[dcdc]->table[vsel];
 342                 int uV = mV * 1000;
 343
 344                 /* Break at the first in-range value */
 345                 if (min_uV <= uV && uV <= max_uV)
 346                         break;
 347         }
 348
 349         /* write to the register in case we found a match */
 350         if (vsel == tps->info[dcdc]->table_len)
 351                 return -EINVAL;
 352         else
 353                 return tps_65023_reg_write(tps, TPS65023_REG_DEF_CORE, vsel);
 354 }
 355
 356 static int tps65023_ldo_get_voltage(struct regulator_dev *dev)
 357 {
 358         struct tps_pmic *tps = rdev_get_drvdata(dev);
 359         int data, ldo = rdev_get_id(dev);
 360
 361         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 362                 return -EINVAL;
 363
 364         data = tps_65023_reg_read(tps, TPS65023_REG_LDO_CTRL);
 365         if (data < 0)
 366                 return data;
 367
 368         data >>= (TPS65023_LDO_CTRL_LDOx_SHIFT(ldo - TPS65023_LDO_1));
 369         data &= (tps->info[ldo]->table_len - 1);
 370         return tps->info[ldo]->table[data] * 1000;
 371 }
 372
 373 static int tps65023_ldo_set_voltage(struct regulator_dev *dev,
 374                                 int min_uV, int max_uV)
 375 {
 376         struct tps_pmic *tps = rdev_get_drvdata(dev);
 377         int data, vsel, ldo = rdev_get_id(dev);
 378
 379         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 380                 return -EINVAL;
 381
 382         if (min_uV < tps->info[ldo]->min_uV || min_uV > tps->info[ldo]->max_uV)
 383                 return -EINVAL;
 384         if (max_uV < tps->info[ldo]->min_uV || max_uV > tps->info[ldo]->max_uV)
 385                 return -EINVAL;
 386
 387         for (vsel = 0; vsel < tps->info[ldo]->table_len; vsel++) {
 388                 int mV = tps->info[ldo]->table[vsel];
 389                 int uV = mV * 1000;
 390
 391                 /* Break at the first in-range value */
 392                 if (min_uV <= uV && uV <= max_uV)
 393                         break;
 394         }
 395
 396         if (vsel == tps->info[ldo]->table_len)
 397                 return -EINVAL;
 398
 399         data = tps_65023_reg_read(tps, TPS65023_REG_LDO_CTRL);
 400         if (data < 0)
 401                 return data;
 402
 403         data &= TPS65023_LDO_CTRL_LDOx_MASK(ldo - TPS65023_LDO_1);
 404         data |= (vsel << (TPS65023_LDO_CTRL_LDOx_SHIFT(ldo - TPS65023_LDO_1)));
 405         return tps_65023_reg_write(tps, TPS65023_REG_LDO_CTRL, data);
 406 }
 407
 408 static int tps65023_dcdc_list_voltage(struct regulator_dev *dev,
 409                                         unsigned selector)
 410 {
 411         struct tps_pmic *tps = rdev_get_drvdata(dev);
 412         int dcdc = rdev_get_id(dev);
 413
 414         if (dcdc < TPS65023_DCDC_1 || dcdc > TPS65023_DCDC_3)
 415                 return -EINVAL;
 416
 417         if (dcdc == TPS65023_DCDC_1) {
 418                 if (selector >= tps->info[dcdc]->table_len)
 419                         return -EINVAL;
 420                 else
 421                         return tps->info[dcdc]->table[selector] * 1000;
 422         } else
 423                 return tps->info[dcdc]->min_uV;
 424 }
 425
 426 static int tps65023_ldo_list_voltage(struct regulator_dev *dev,
 427                                         unsigned selector)
 428 {
 429         struct tps_pmic *tps = rdev_get_drvdata(dev);
 430         int ldo = rdev_get_id(dev);
 431
 432         if (ldo < TPS65023_LDO_1 || ldo > TPS65023_LDO_2)
 433                 return -EINVAL;
 434
 435         if (selector >= tps->info[ldo]->table_len)
 436                 return -EINVAL;
 437         else
 438                 return tps->info[ldo]->table[selector] * 1000;
 439 }
 440
 441 /* Operations permitted on VDCDCx */
 442 static struct regulator_ops tps65023_dcdc_ops = {
 443         .is_enabled = tps65023_dcdc_is_enabled,
 444         .enable = tps65023_dcdc_enable,
 445         .disable = tps65023_dcdc_disable,
 446         .get_voltage = tps65023_dcdc_get_voltage,
 447         .set_voltage = tps65023_dcdc_set_voltage,
 448         .list_voltage = tps65023_dcdc_list_voltage,
 449 };
 450
 451 /* Operations permitted on LDOx */
 452 static struct regulator_ops tps65023_ldo_ops = {
 453         .is_enabled = tps65023_ldo_is_enabled,
 454         .enable = tps65023_ldo_enable,
 455         .disable = tps65023_ldo_disable,
 456         .get_voltage = tps65023_ldo_get_voltage,
 457         .set_voltage = tps65023_ldo_set_voltage,
 458         .list_voltage = tps65023_ldo_list_voltage,
 459 };
 460
 461 static int __devinit tps_65023_probe(struct i2c_client *client,
 462                                      const struct i2c_device_id *id)
 463 {
 464         static int desc_id;
 465         const struct tps_info *info = (void *)id->driver_data;
 466         struct regulator_init_data *init_data;
 467         struct regulator_dev *rdev;
 468         struct tps_pmic *tps;
 469         int i;
 470         int error;
 471
 472         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 473                 return -EIO;
 474
 475         /**
 476          * init_data points to array of regulator_init structures
 477          * coming from the board-evm file.
 478          */
 479         init_data = client->dev.platform_data;
 480         if (!init_data)
 481                 return -EIO;
 482
 483         tps = kzalloc(sizeof(*tps), GFP_KERNEL);
 484         if (!tps)
 485                 return -ENOMEM;
 486
 487         mutex_init(&tps->io_lock);
 488
 489         /* common for all regulators */
 490         tps->client = client;
 491
 492         for (i = 0; i < TPS65023_NUM_REGULATOR; i++, info++, init_data++) {
 493                 /* Store regulator specific information */
 494                 tps->info[i] = info;
 495
 496                 tps->desc[i].name = info->name;
 497                 tps->desc[i].id = desc_id++;
 498                 tps->desc[i].n_voltages = num_voltages[i];
 499                 tps->desc[i].ops = (i > TPS65023_DCDC_3 ?
 500                                         &tps65023_ldo_ops : &tps65023_dcdc_ops);
 501                 tps->desc[i].type = REGULATOR_VOLTAGE;
 502                 tps->desc[i].owner = THIS_MODULE;
 503
 504                 /* Register the regulators */
 505                 rdev = regulator_register(&tps->desc[i], &client->dev,
 506                                           init_data, tps);
 507                 if (IS_ERR(rdev)) {
 508                         dev_err(&client->dev, "failed to register %s\n",
 509                                 id->name);
 510                         error = PTR_ERR(rdev);
 511                         goto fail;
 512                 }
 513
 514                 /* Save regulator for cleanup */
 515                 tps->rdev[i] = rdev;
 516         }
 517
 518         i2c_set_clientdata(client, tps);
 519
 520         return 0;
 521
 522  fail:
 523         while (--i >= 0)
 524                 regulator_unregister(tps->rdev[i]);
 525
 526         kfree(tps);
 527         return error;
 528 }
 529
 530 /**
 531  * tps_65023_remove - TPS65023 driver i2c remove handler
 532  * @client: i2c driver client device structure
 533  *
 534  * Unregister TPS driver as an i2c client device driver
 535  */
 536 static int __devexit tps_65023_remove(struct i2c_client *client)
 537 {
 538         struct tps_pmic *tps = i2c_get_clientdata(client);
 539         int i;
 540
 541         for (i = 0; i < TPS65023_NUM_REGULATOR; i++)
 542                 regulator_unregister(tps->rdev[i]);
 543
 544         kfree(tps);
 545
 546         return 0;
 547 }
 548
 549 static const struct tps_info tps65023_regs[] = {
 550         {
 551                 .name = "VDCDC1",
 552                 .min_uV =  800000,
 553                 .max_uV = 1600000,
 554                 .table_len = ARRAY_SIZE(VDCDC1_VSEL_table),
 555                 .table = VDCDC1_VSEL_table,
 556         },
 557         {
 558                 .name = "VDCDC2",
 559                 .min_uV =  3300000,
 560                 .max_uV = 3300000,
 561                 .fixed = 1,
 562         },
 563         {
 564                 .name = "VDCDC3",
 565                 .min_uV =  1800000,
 566                 .max_uV = 1800000,
 567                 .fixed = 1,
 568         },
 569         {
 570                 .name = "LDO1",
 571                 .min_uV = 1000000,
 572                 .max_uV = 3150000,
 573                 .table_len = ARRAY_SIZE(LDO1_VSEL_table),
 574                 .table = LDO1_VSEL_table,
 575         },
 576         {
 577                 .name = "LDO2",
 578                 .min_uV = 1050000,
 579                 .max_uV = 3300000,
 580                 .table_len = ARRAY_SIZE(LDO2_VSEL_table),
 581                 .table = LDO2_VSEL_table,
 582         },
 583 };
 584
 585 static const struct i2c_device_id tps_65023_id[] = {
 586         {.name = "tps65023",
 587         .driver_data = (unsigned long) tps65023_regs,},
 588         { },
 589 };
 590
 591 MODULE_DEVICE_TABLE(i2c, tps_65023_id);
 592
 593 static struct i2c_driver tps_65023_i2c_driver = {
 594         .driver = {
 595                 .name = "tps65023",
 596                 .owner = THIS_MODULE,
 597         },
 598         .probe = tps_65023_probe,
 599         .remove = __devexit_p(tps_65023_remove),
 600         .id_table = tps_65023_id,
 601 };
 602
 603 /**
 604  * tps_65023_init
 605  *
 606  * Module init function
 607  */
 608 static int __init tps_65023_init(void)
 609 {
 610         return i2c_add_driver(&tps_65023_i2c_driver);
 611 }
 612 subsys_initcall(tps_65023_init);
 613
 614 /**
 615  * tps_65023_cleanup
 616  *
 617  * Module exit function
 618  */
 619 static void __exit tps_65023_cleanup(void)
 620 {
 621         i2c_del_driver(&tps_65023_i2c_driver);
 622 }
 623 module_exit(tps_65023_cleanup);
 624
 625 MODULE_AUTHOR("Texas Instruments");
 626 MODULE_DESCRIPTION("TPS65023 voltage regulator driver");
 627 MODULE_LICENSE("GPL v2");