drivers/regulator/tps62360-regulator.c

   1 /*
   2  * tps62360.c -- TI tps62360
   3  *
   4  * Driver for processor core supply tps62360 and tps62361B
   5  *
   6  * Copyright (c) 2012, NVIDIA Corporation.
   7  *
   8  * Author: Laxman Dewangan <ldewangan@nvidia.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation version 2.
  13  *
  14  * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
  15  * whether express or implied; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  22  * 02111-1307, USA
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/module.h>
  27 #include <linux/init.h>
  28 #include <linux/err.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/regulator/driver.h>
  31 #include <linux/regulator/machine.h>
  32 #include <linux/regulator/tps62360.h>
  33 #include <linux/gpio.h>
  34 #include <linux/i2c.h>
  35 #include <linux/delay.h>
  36 #include <linux/slab.h>
  37 #include <linux/regmap.h>
  38
  39 /* Register definitions */
  40 #define REG_VSET0               0
  41 #define REG_VSET1               1
  42 #define REG_VSET2               2
  43 #define REG_VSET3               3
  44 #define REG_CONTROL             4
  45 #define REG_TEMP                5
  46 #define REG_RAMPCTRL            6
  47 #define REG_CHIPID              8
  48
  49 enum chips {TPS62360, TPS62361};
  50
  51 #define TPS62360_BASE_VOLTAGE   770
  52 #define TPS62360_N_VOLTAGES     64
  53
  54 #define TPS62361_BASE_VOLTAGE   500
  55 #define TPS62361_N_VOLTAGES     128
  56
  57 /* tps 62360 chip information */
  58 struct tps62360_chip {
  59         const char *name;
  60         struct device *dev;
  61         struct regulator_desc desc;
  62         struct i2c_client *client;
  63         struct regulator_dev *rdev;
  64         struct regmap *regmap;
  65         int chip_id;
  66         int vsel0_gpio;
  67         int vsel1_gpio;
  68         int voltage_base;
  69         u8 voltage_reg_mask;
  70         bool en_internal_pulldn;
  71         bool en_force_pwm;
  72         bool en_discharge;
  73         bool valid_gpios;
  74         int lru_index[4];
  75         int curr_vset_vsel[4];
  76         int curr_vset_id;
  77 };
  78
  79 /*
  80  * find_voltage_set_register: Find new voltage configuration register
  81  * (VSET) id.
  82  * The finding of the new VSET register will be based on the LRU mechanism.
  83  * Each VSET register will have different voltage configured . This
  84  * Function will look if any of the VSET register have requested voltage set
  85  * or not.
  86  *     - If it is already there then it will make that register as most
  87  *       recently used and return as found so that caller need not to set
  88  *       the VSET register but need to set the proper gpios to select this
  89  *       VSET register.
  90  *     - If requested voltage is not found then it will use the least
  91  *       recently mechanism to get new VSET register for new configuration
  92  *       and will return not_found so that caller need to set new VSET
  93  *       register and then gpios (both).
  94  */
  95 static bool find_voltage_set_register(struct tps62360_chip *tps,
  96                 int req_vsel, int *vset_reg_id)
  97 {
  98         int i;
  99         bool found = false;
 100         int new_vset_reg = tps->lru_index[3];
 101         int found_index = 3;
 102         for (i = 0; i < 4; ++i) {
 103                 if (tps->curr_vset_vsel[tps->lru_index[i]] == req_vsel) {
 104                         new_vset_reg = tps->lru_index[i];
 105                         found_index = i;
 106                         found = true;
 107                         goto update_lru_index;
 108                 }
 109         }
 110
 111 update_lru_index:
 112         for (i = found_index; i > 0; i--)
 113                 tps->lru_index[i] = tps->lru_index[i - 1];
 114
 115         tps->lru_index[0] = new_vset_reg;
 116         *vset_reg_id = new_vset_reg;
 117         return found;
 118 }
 119
 120 static int tps62360_dcdc_get_voltage(struct regulator_dev *dev)
 121 {
 122         struct tps62360_chip *tps = rdev_get_drvdata(dev);
 123         int vsel;
 124         unsigned int data;
 125         int ret;
 126
 127         ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
 128         if (ret < 0) {
 129                 dev_err(tps->dev, "%s: Error in reading register %d\n",
 130                         __func__, REG_VSET0 + tps->curr_vset_id);
 131                 return ret;
 132         }
 133         vsel = (int)data & tps->voltage_reg_mask;
 134         return (tps->voltage_base + vsel * 10) * 1000;
 135 }
 136
 137 static int tps62360_dcdc_set_voltage(struct regulator_dev *dev,
 138              int min_uV, int max_uV, unsigned *selector)
 139 {
 140         struct tps62360_chip *tps = rdev_get_drvdata(dev);
 141         int vsel;
 142         int ret;
 143         bool found = false;
 144         int new_vset_id = tps->curr_vset_id;
 145
 146         if (max_uV < min_uV)
 147                 return -EINVAL;
 148
 149         if (min_uV >
 150                 ((tps->voltage_base + (tps->desc.n_voltages - 1) * 10) * 1000))
 151                 return -EINVAL;
 152
 153         if (max_uV < tps->voltage_base * 1000)
 154                 return -EINVAL;
 155
 156         vsel = DIV_ROUND_UP(min_uV - (tps->voltage_base * 1000), 10000);
 157         if (selector)
 158                 *selector = (vsel & tps->voltage_reg_mask);
 159
 160         /*
 161          * If gpios are available to select the VSET register then least
 162          * recently used register for new configuration.
 163          */
 164         if (tps->valid_gpios)
 165                 found = find_voltage_set_register(tps, vsel, &new_vset_id);
 166
 167         if (!found) {
 168                 ret = regmap_update_bits(tps->regmap, REG_VSET0 + new_vset_id,
 169                                 tps->voltage_reg_mask, vsel);
 170                 if (ret < 0) {
 171                         dev_err(tps->dev, "%s: Error in updating register %d\n",
 172                                  __func__, REG_VSET0 + new_vset_id);
 173                         return ret;
 174                 }
 175                 tps->curr_vset_id = new_vset_id;
 176                 tps->curr_vset_vsel[new_vset_id] = vsel;
 177         }
 178
 179         /* Select proper VSET register vio gpios */
 180         if (tps->valid_gpios) {
 181                 gpio_set_value_cansleep(tps->vsel0_gpio,
 182                                         new_vset_id & 0x1);
 183                 gpio_set_value_cansleep(tps->vsel1_gpio,
 184                                         (new_vset_id >> 1) & 0x1);
 185         }
 186         return 0;
 187 }
 188
 189 static int tps62360_dcdc_list_voltage(struct regulator_dev *dev,
 190                                         unsigned selector)
 191 {
 192         struct tps62360_chip *tps = rdev_get_drvdata(dev);
 193
 194         if (selector >= tps->desc.n_voltages)
 195                 return -EINVAL;
 196         return (tps->voltage_base + selector * 10) * 1000;
 197 }
 198
 199 static struct regulator_ops tps62360_dcdc_ops = {
 200         .get_voltage = tps62360_dcdc_get_voltage,
 201         .set_voltage = tps62360_dcdc_set_voltage,
 202         .list_voltage = tps62360_dcdc_list_voltage,
 203 };
 204
 205 static int tps62360_init_force_pwm(struct tps62360_chip *tps,
 206         struct tps62360_regulator_platform_data *pdata,
 207         int vset_id)
 208 {
 209         unsigned int data;
 210         int ret;
 211         ret = regmap_read(tps->regmap, REG_VSET0 + vset_id, &data);
 212         if (ret < 0) {
 213                 dev_err(tps->dev, "%s() fails in writing reg %d\n",
 214                         __func__, REG_VSET0 + vset_id);
 215                 return ret;
 216         }
 217         tps->curr_vset_vsel[vset_id] = data & tps->voltage_reg_mask;
 218         if (pdata->en_force_pwm)
 219                 data |= BIT(7);
 220         else
 221                 data &= ~BIT(7);
 222         ret = regmap_write(tps->regmap, REG_VSET0 + vset_id, data);
 223         if (ret < 0)
 224                 dev_err(tps->dev, "%s() fails in writing reg %d\n",
 225                                 __func__, REG_VSET0 + vset_id);
 226         return ret;
 227 }
 228
 229 static int tps62360_init_dcdc(struct tps62360_chip *tps,
 230                 struct tps62360_regulator_platform_data *pdata)
 231 {
 232         int ret;
 233         int i;
 234
 235         /* Initailize internal pull up/down control */
 236         if (tps->en_internal_pulldn)
 237                 ret = regmap_write(tps->regmap, REG_CONTROL, 0xE0);
 238         else
 239                 ret = regmap_write(tps->regmap, REG_CONTROL, 0x0);
 240         if (ret < 0) {
 241                 dev_err(tps->dev, "%s() fails in writing reg %d\n",
 242                         __func__, REG_CONTROL);
 243                 return ret;
 244         }
 245
 246         /* Initailize force PWM mode */
 247         if (tps->valid_gpios) {
 248                 for (i = 0; i < 4; ++i) {
 249                         ret = tps62360_init_force_pwm(tps, pdata, i);
 250                         if (ret < 0)
 251                                 return ret;
 252                 }
 253         } else {
 254                 ret = tps62360_init_force_pwm(tps, pdata, tps->curr_vset_id);
 255                 if (ret < 0)
 256                         return ret;
 257         }
 258
 259         /* Reset output discharge path to reduce power consumption */
 260         ret = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), 0);
 261         if (ret < 0)
 262                 dev_err(tps->dev, "%s() fails in updating reg %d\n",
 263                         __func__, REG_RAMPCTRL);
 264         return ret;
 265 }
 266
 267 static const struct regmap_config tps62360_regmap_config = {
 268         .reg_bits = 8,
 269         .val_bits = 8,
 270 };
 271
 272 static int __devinit tps62360_probe(struct i2c_client *client,
 273                                      const struct i2c_device_id *id)
 274 {
 275         struct tps62360_regulator_platform_data *pdata;
 276         struct regulator_dev *rdev;
 277         struct tps62360_chip *tps;
 278         int ret;
 279         int i;
 280
 281         pdata = client->dev.platform_data;
 282         if (!pdata) {
 283                 dev_err(&client->dev, "%s() Err: Platform data not found\n",
 284                                                 __func__);
 285                 return -EIO;
 286         }
 287
 288         tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
 289         if (!tps) {
 290                 dev_err(&client->dev, "%s() Err: Memory allocation fails\n",
 291                                                 __func__);
 292                 return -ENOMEM;
 293         }
 294
 295         tps->en_force_pwm = pdata->en_force_pwm;
 296         tps->en_discharge = pdata->en_discharge;
 297         tps->en_internal_pulldn = pdata->en_internal_pulldn;
 298         tps->vsel0_gpio = pdata->vsel0_gpio;
 299         tps->vsel1_gpio = pdata->vsel1_gpio;
 300         tps->client = client;
 301         tps->dev = &client->dev;
 302         tps->name = id->name;
 303         tps->voltage_base = (id->driver_data == TPS62360) ?
 304                                 TPS62360_BASE_VOLTAGE : TPS62361_BASE_VOLTAGE;
 305         tps->voltage_reg_mask = (id->driver_data == TPS62360) ? 0x3F : 0x7F;
 306
 307         tps->desc.name = id->name;
 308         tps->desc.id = 0;
 309         tps->desc.n_voltages = (id->driver_data == TPS62360) ?
 310                                 TPS62360_N_VOLTAGES : TPS62361_N_VOLTAGES;
 311         tps->desc.ops = &tps62360_dcdc_ops;
 312         tps->desc.type = REGULATOR_VOLTAGE;
 313         tps->desc.owner = THIS_MODULE;
 314         tps->regmap = regmap_init_i2c(client, &tps62360_regmap_config);
 315         if (IS_ERR(tps->regmap)) {
 316                 ret = PTR_ERR(tps->regmap);
 317                 dev_err(&client->dev, "%s() Err: Failed to allocate register"
 318                         "map: %d\n", __func__, ret);
 319                 return ret;
 320         }
 321         i2c_set_clientdata(client, tps);
 322
 323         tps->curr_vset_id = (pdata->vsel1_def_state & 1) * 2 +
 324                                 (pdata->vsel0_def_state & 1);
 325         tps->lru_index[0] = tps->curr_vset_id;
 326         tps->valid_gpios = false;
 327
 328         if (gpio_is_valid(tps->vsel0_gpio) && gpio_is_valid(tps->vsel1_gpio)) {
 329                 ret = gpio_request(tps->vsel0_gpio, "tps62360-vsel0");
 330                 if (ret) {
 331                         dev_err(&client->dev,
 332                                 "Err: Could not obtain vsel0 GPIO %d: %d\n",
 333                                                 tps->vsel0_gpio, ret);
 334                         goto err_gpio0;
 335                 }
 336                 ret = gpio_direction_output(tps->vsel0_gpio,
 337                                         pdata->vsel0_def_state);
 338                 if (ret) {
 339                         dev_err(&client->dev, "Err: Could not set direction of"
 340                                 "vsel0 GPIO %d: %d\n", tps->vsel0_gpio, ret);
 341                         gpio_free(tps->vsel0_gpio);
 342                         goto err_gpio0;
 343                 }
 344
 345                 ret = gpio_request(tps->vsel1_gpio, "tps62360-vsel1");
 346                 if (ret) {
 347                         dev_err(&client->dev,
 348                                 "Err: Could not obtain vsel1 GPIO %d: %d\n",
 349                                                 tps->vsel1_gpio, ret);
 350                         goto err_gpio1;
 351                 }
 352                 ret = gpio_direction_output(tps->vsel1_gpio,
 353                                         pdata->vsel1_def_state);
 354                 if (ret) {
 355                         dev_err(&client->dev, "Err: Could not set direction of"
 356                                 "vsel1 GPIO %d: %d\n", tps->vsel1_gpio, ret);
 357                         gpio_free(tps->vsel1_gpio);
 358                         goto err_gpio1;
 359                 }
 360                 tps->valid_gpios = true;
 361
 362                 /*
 363                  * Initialize the lru index with vset_reg id
 364                  * The index 0 will be most recently used and
 365                  * set with the tps->curr_vset_id */
 366                 for (i = 0; i < 4; ++i)
 367                         tps->lru_index[i] = i;
 368                 tps->lru_index[0] = tps->curr_vset_id;
 369                 tps->lru_index[tps->curr_vset_id] = 0;
 370         }
 371
 372         ret = tps62360_init_dcdc(tps, pdata);
 373         if (ret < 0) {
 374                 dev_err(tps->dev, "%s() Err: Init fails with = %d\n",
 375                                 __func__, ret);
 376                 goto err_init;
 377         }
 378
 379         /* Register the regulators */
 380         rdev = regulator_register(&tps->desc, &client->dev,
 381                                 &pdata->reg_init_data, tps, NULL);
 382         if (IS_ERR(rdev)) {
 383                 dev_err(tps->dev, "%s() Err: Failed to register %s\n",
 384                                 __func__, id->name);
 385                 ret = PTR_ERR(rdev);
 386                 goto err_init;
 387         }
 388
 389         tps->rdev = rdev;
 390         return 0;
 391
 392 err_init:
 393         if (gpio_is_valid(tps->vsel1_gpio))
 394                 gpio_free(tps->vsel1_gpio);
 395 err_gpio1:
 396         if (gpio_is_valid(tps->vsel0_gpio))
 397                 gpio_free(tps->vsel0_gpio);
 398 err_gpio0:
 399         regmap_exit(tps->regmap);
 400         return ret;
 401 }
 402
 403 /**
 404  * tps62360_remove - tps62360 driver i2c remove handler
 405  * @client: i2c driver client device structure
 406  *
 407  * Unregister TPS driver as an i2c client device driver
 408  */
 409 static int __devexit tps62360_remove(struct i2c_client *client)
 410 {
 411         struct tps62360_chip *tps = i2c_get_clientdata(client);
 412
 413         if (gpio_is_valid(tps->vsel1_gpio))
 414                 gpio_free(tps->vsel1_gpio);
 415
 416         if (gpio_is_valid(tps->vsel0_gpio))
 417                 gpio_free(tps->vsel0_gpio);
 418
 419         regulator_unregister(tps->rdev);
 420         regmap_exit(tps->regmap);
 421         return 0;
 422 }
 423
 424 static void tps62360_shutdown(struct i2c_client *client)
 425 {
 426         struct tps62360_chip *tps = i2c_get_clientdata(client);
 427         int st;
 428
 429         if (!tps->en_discharge)
 430                 return;
 431
 432         /* Configure the output discharge path */
 433         st = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), BIT(2));
 434         if (st < 0)
 435                 dev_err(tps->dev, "%s() fails in updating reg %d\n",
 436                         __func__, REG_RAMPCTRL);
 437 }
 438
 439 static const struct i2c_device_id tps62360_id[] = {
 440         {.name = "tps62360", .driver_data = TPS62360},
 441         {.name = "tps62361", .driver_data = TPS62361},
 442         {},
 443 };
 444
 445 MODULE_DEVICE_TABLE(i2c, tps62360_id);
 446
 447 static struct i2c_driver tps62360_i2c_driver = {
 448         .driver = {
 449                 .name = "tps62360",
 450                 .owner = THIS_MODULE,
 451         },
 452         .probe = tps62360_probe,
 453         .remove = __devexit_p(tps62360_remove),
 454         .shutdown = tps62360_shutdown,
 455         .id_table = tps62360_id,
 456 };
 457
 458 static int __init tps62360_init(void)
 459 {
 460         return i2c_add_driver(&tps62360_i2c_driver);
 461 }
 462 subsys_initcall(tps62360_init);
 463
 464 static void __exit tps62360_cleanup(void)
 465 {
 466         i2c_del_driver(&tps62360_i2c_driver);
 467 }
 468 module_exit(tps62360_cleanup);
 469
 470 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 471 MODULE_DESCRIPTION("TPS62360 voltage regulator driver");
 472 MODULE_LICENSE("GPL v2");