drivers/regulator/tps62360-regulator.c

   1 /*
   2  * tps62360.c -- TI tps62360
   3  *
   4  * Driver for processor core supply tps62360, tps62361B, tps62362 and tps62363.
   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/of.h>
  30 #include <linux/of_device.h>
  31 #include <linux/of_gpio.h>
  32 #include <linux/regulator/of_regulator.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/regulator/driver.h>
  35 #include <linux/regulator/machine.h>
  36 #include <linux/regulator/tps62360.h>
  37 #include <linux/gpio.h>
  38 #include <linux/i2c.h>
  39 #include <linux/slab.h>
  40 #include <linux/regmap.h>
  41
  42 /* Register definitions */
  43 #define REG_VSET0               0
  44 #define REG_VSET1               1
  45 #define REG_VSET2               2
  46 #define REG_VSET3               3
  47 #define REG_CONTROL             4
  48 #define REG_TEMP                5
  49 #define REG_RAMPCTRL            6
  50 #define REG_CHIPID              8
  51
  52 enum chips {TPS62360, TPS62361, TPS62362, TPS62363};
  53
  54 #define TPS62360_BASE_VOLTAGE   770000
  55 #define TPS62360_N_VOLTAGES     64
  56
  57 #define TPS62361_BASE_VOLTAGE   500000
  58 #define TPS62361_N_VOLTAGES     128
  59
  60 /* tps 62360 chip information */
  61 struct tps62360_chip {
  62         struct device *dev;
  63         struct regulator_desc desc;
  64         struct regulator_dev *rdev;
  65         struct regmap *regmap;
  66         int chip_id;
  67         int vsel0_gpio;
  68         int vsel1_gpio;
  69         int voltage_base;
  70         u8 voltage_reg_mask;
  71         bool en_internal_pulldn;
  72         bool en_force_pwm;
  73         bool en_discharge;
  74         bool valid_gpios;
  75         int lru_index[4];
  76         int curr_vset_vsel[4];
  77         int curr_vset_id;
  78         int change_uv_per_us;
  79 };
  80
  81 /*
  82  * find_voltage_set_register: Find new voltage configuration register
  83  * (VSET) id.
  84  * The finding of the new VSET register will be based on the LRU mechanism.
  85  * Each VSET register will have different voltage configured . This
  86  * Function will look if any of the VSET register have requested voltage set
  87  * or not.
  88  *     - If it is already there then it will make that register as most
  89  *       recently used and return as found so that caller need not to set
  90  *       the VSET register but need to set the proper gpios to select this
  91  *       VSET register.
  92  *     - If requested voltage is not found then it will use the least
  93  *       recently mechanism to get new VSET register for new configuration
  94  *       and will return not_found so that caller need to set new VSET
  95  *       register and then gpios (both).
  96  */
  97 static bool find_voltage_set_register(struct tps62360_chip *tps,
  98                 int req_vsel, int *vset_reg_id)
  99 {
 100         int i;
 101         bool found = false;
 102         int new_vset_reg = tps->lru_index[3];
 103         int found_index = 3;
 104
 105         for (i = 0; i < 4; ++i) {
 106                 if (tps->curr_vset_vsel[tps->lru_index[i]] == req_vsel) {
 107                         new_vset_reg = tps->lru_index[i];
 108                         found_index = i;
 109                         found = true;
 110                         goto update_lru_index;
 111                 }
 112         }
 113
 114 update_lru_index:
 115         for (i = found_index; i > 0; i--)
 116                 tps->lru_index[i] = tps->lru_index[i - 1];
 117
 118         tps->lru_index[0] = new_vset_reg;
 119         *vset_reg_id = new_vset_reg;
 120         return found;
 121 }
 122
 123 static int tps62360_dcdc_get_voltage_sel(struct regulator_dev *dev)
 124 {
 125         struct tps62360_chip *tps = rdev_get_drvdata(dev);
 126         int vsel;
 127         unsigned int data;
 128         int ret;
 129
 130         ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
 131         if (ret < 0) {
 132                 dev_err(tps->dev, "%s(): register %d read failed with err %d\n",
 133                         __func__, REG_VSET0 + tps->curr_vset_id, ret);
 134                 return ret;
 135         }
 136         vsel = (int)data & tps->voltage_reg_mask;
 137         return vsel;
 138 }
 139
 140 static int tps62360_dcdc_set_voltage(struct regulator_dev *dev,
 141              int min_uV, int max_uV, unsigned *selector)
 142 {
 143         struct tps62360_chip *tps = rdev_get_drvdata(dev);
 144         int vsel;
 145         int ret;
 146         bool found = false;
 147         int new_vset_id = tps->curr_vset_id;
 148
 149         if ((max_uV < min_uV) || (max_uV < tps->voltage_base))
 150                 return -EINVAL;
 151
 152         if (min_uV > (tps->voltage_base + (tps->desc.n_voltages - 1) * 10000))
 153                 return -EINVAL;
 154
 155         vsel = DIV_ROUND_UP(min_uV - tps->voltage_base, 10000);
 156         if (selector)
 157                 *selector = (vsel & tps->voltage_reg_mask);
 158
 159         /*
 160          * If gpios are available to select the VSET register then least
 161          * recently used register for new configuration.
 162          */
 163         if (tps->valid_gpios)
 164                 found = find_voltage_set_register(tps, vsel, &new_vset_id);
 165
 166         if (!found) {
 167                 ret = regmap_update_bits(tps->regmap, REG_VSET0 + new_vset_id,
 168                                 tps->voltage_reg_mask, vsel);
 169                 if (ret < 0) {
 170                         dev_err(tps->dev,
 171                                 "%s(): register %d update failed with err %d\n",
 172                                  __func__, REG_VSET0 + new_vset_id, ret);
 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, new_vset_id & 0x1);
 182                 gpio_set_value_cansleep(tps->vsel1_gpio,
 183                                         (new_vset_id >> 1) & 0x1);
 184         }
 185         return 0;
 186 }
 187
 188 static int tps62360_set_voltage_time_sel(struct regulator_dev *rdev,
 189                 unsigned int old_selector, unsigned int new_selector)
 190 {
 191         struct tps62360_chip *tps = rdev_get_drvdata(rdev);
 192         int old_uV, new_uV;
 193
 194         old_uV = regulator_list_voltage_linear(rdev, old_selector);
 195         if (old_uV < 0)
 196                 return old_uV;
 197
 198         new_uV = regulator_list_voltage_linear(rdev, new_selector);
 199         if (new_uV < 0)
 200                 return new_uV;
 201
 202         return DIV_ROUND_UP(abs(old_uV - new_uV), tps->change_uv_per_us);
 203 }
 204
 205 static struct regulator_ops tps62360_dcdc_ops = {
 206         .get_voltage_sel        = tps62360_dcdc_get_voltage_sel,
 207         .set_voltage            = tps62360_dcdc_set_voltage,
 208         .list_voltage           = regulator_list_voltage_linear,
 209         .set_voltage_time_sel   = tps62360_set_voltage_time_sel,
 210 };
 211
 212 static int __devinit tps62360_init_force_pwm(struct tps62360_chip *tps,
 213         struct tps62360_regulator_platform_data *pdata,
 214         int vset_id)
 215 {
 216         int ret;
 217         int bit = 0;
 218
 219         if (pdata->en_force_pwm)
 220                 bit = BIT(7);
 221
 222         ret = regmap_update_bits(tps->regmap, REG_VSET0 + vset_id, BIT(7), bit);
 223         if (ret < 0)
 224                 dev_err(tps->dev,
 225                         "%s(): register %d update failed with err %d\n",
 226                         __func__, REG_VSET0 + vset_id, ret);
 227         return ret;
 228 }
 229
 230 static int __devinit tps62360_init_dcdc(struct tps62360_chip *tps,
 231                 struct tps62360_regulator_platform_data *pdata)
 232 {
 233         int ret;
 234         int i;
 235         unsigned int ramp_ctrl;
 236
 237         /* Initialize internal pull up/down control */
 238         if (tps->en_internal_pulldn)
 239                 ret = regmap_write(tps->regmap, REG_CONTROL, 0xE0);
 240         else
 241                 ret = regmap_write(tps->regmap, REG_CONTROL, 0x0);
 242         if (ret < 0) {
 243                 dev_err(tps->dev,
 244                         "%s(): register %d write failed with err %d\n",
 245                         __func__, REG_CONTROL, ret);
 246                 return ret;
 247         }
 248
 249         /* Initialize force PWM mode */
 250         if (tps->valid_gpios) {
 251                 for (i = 0; i < 4; ++i) {
 252                         ret = tps62360_init_force_pwm(tps, pdata, i);
 253                         if (ret < 0)
 254                                 return ret;
 255                 }
 256         } else {
 257                 ret = tps62360_init_force_pwm(tps, pdata, tps->curr_vset_id);
 258                 if (ret < 0)
 259                         return ret;
 260         }
 261
 262         /* Reset output discharge path to reduce power consumption */
 263         ret = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), 0);
 264         if (ret < 0) {
 265                 dev_err(tps->dev,
 266                         "%s(): register %d update failed with err %d\n",
 267                         __func__, REG_RAMPCTRL, ret);
 268                 return ret;
 269         }
 270
 271         /* Get ramp value from ramp control register */
 272         ret = regmap_read(tps->regmap, REG_RAMPCTRL, &ramp_ctrl);
 273         if (ret < 0) {
 274                 dev_err(tps->dev,
 275                         "%s(): register %d read failed with err %d\n",
 276                         __func__, REG_RAMPCTRL, ret);
 277                 return ret;
 278         }
 279         ramp_ctrl = (ramp_ctrl >> 4) & 0x7;
 280
 281         /* ramp mV/us = 32/(2^ramp_ctrl) */
 282         tps->change_uv_per_us = DIV_ROUND_UP(32000, BIT(ramp_ctrl));
 283         return ret;
 284 }
 285
 286 static const struct regmap_config tps62360_regmap_config = {
 287         .reg_bits               = 8,
 288         .val_bits               = 8,
 289         .max_register           = REG_CHIPID,
 290         .cache_type             = REGCACHE_RBTREE,
 291 };
 292
 293 static struct tps62360_regulator_platform_data *
 294         of_get_tps62360_platform_data(struct device *dev)
 295 {
 296         struct tps62360_regulator_platform_data *pdata;
 297         struct device_node *np = dev->of_node;
 298
 299         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 300         if (!pdata) {
 301                 dev_err(dev, "Memory alloc failed for platform data\n");
 302                 return NULL;
 303         }
 304
 305         pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node);
 306         if (!pdata->reg_init_data) {
 307                 dev_err(dev, "Not able to get OF regulator init data\n");
 308                 return NULL;
 309         }
 310
 311         pdata->vsel0_gpio = of_get_named_gpio(np, "vsel0-gpio", 0);
 312         pdata->vsel1_gpio = of_get_named_gpio(np, "vsel1-gpio", 0);
 313
 314         if (of_find_property(np, "ti,vsel0-state-high", NULL))
 315                 pdata->vsel0_def_state = 1;
 316
 317         if (of_find_property(np, "ti,vsel1-state-high", NULL))
 318                 pdata->vsel1_def_state = 1;
 319
 320         if (of_find_property(np, "ti,enable-pull-down", NULL))
 321                 pdata->en_internal_pulldn = true;
 322
 323         if (of_find_property(np, "ti,enable-force-pwm", NULL))
 324                 pdata->en_force_pwm = true;
 325
 326         if (of_find_property(np, "ti,enable-vout-discharge", NULL))
 327                 pdata->en_discharge = true;
 328
 329         return pdata;
 330 }
 331
 332 #if defined(CONFIG_OF)
 333 static const struct of_device_id tps62360_of_match[] = {
 334          { .compatible = "ti,tps62360", .data = (void *)TPS62360},
 335          { .compatible = "ti,tps62361", .data = (void *)TPS62361},
 336          { .compatible = "ti,tps62362", .data = (void *)TPS62362},
 337          { .compatible = "ti,tps62363", .data = (void *)TPS62363},
 338         {},
 339 }
 340 MODULE_DEVICE_TABLE(of, tps62360_of_match);
 341 #endif
 342
 343 static int __devinit tps62360_probe(struct i2c_client *client,
 344                                      const struct i2c_device_id *id)
 345 {
 346         struct regulator_config config = { };
 347         struct tps62360_regulator_platform_data *pdata;
 348         struct regulator_dev *rdev;
 349         struct tps62360_chip *tps;
 350         int ret;
 351         int i;
 352         int chip_id;
 353
 354         pdata = client->dev.platform_data;
 355         chip_id = id->driver_data;
 356
 357         if (client->dev.of_node) {
 358                 const struct of_device_id *match;
 359                 match = of_match_device(of_match_ptr(tps62360_of_match),
 360                                 &client->dev);
 361                 if (!match) {
 362                         dev_err(&client->dev, "Error: No device match found\n");
 363                         return -ENODEV;
 364                 }
 365                 chip_id = (int)match->data;
 366                 if (!pdata)
 367                         pdata = of_get_tps62360_platform_data(&client->dev);
 368         }
 369
 370         if (!pdata) {
 371                 dev_err(&client->dev, "%s(): Platform data not found\n",
 372                                                 __func__);
 373                 return -EIO;
 374         }
 375
 376         tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
 377         if (!tps) {
 378                 dev_err(&client->dev, "%s(): Memory allocation failed\n",
 379                                                 __func__);
 380                 return -ENOMEM;
 381         }
 382
 383         tps->en_force_pwm = pdata->en_force_pwm;
 384         tps->en_discharge = pdata->en_discharge;
 385         tps->en_internal_pulldn = pdata->en_internal_pulldn;
 386         tps->vsel0_gpio = pdata->vsel0_gpio;
 387         tps->vsel1_gpio = pdata->vsel1_gpio;
 388         tps->dev = &client->dev;
 389
 390         switch (chip_id) {
 391         case TPS62360:
 392         case TPS62362:
 393                 tps->voltage_base = TPS62360_BASE_VOLTAGE;
 394                 tps->voltage_reg_mask = 0x3F;
 395                 tps->desc.n_voltages = TPS62360_N_VOLTAGES;
 396                 break;
 397         case TPS62361:
 398         case TPS62363:
 399                 tps->voltage_base = TPS62361_BASE_VOLTAGE;
 400                 tps->voltage_reg_mask = 0x7F;
 401                 tps->desc.n_voltages = TPS62361_N_VOLTAGES;
 402                 break;
 403         default:
 404                 return -ENODEV;
 405         }
 406
 407         tps->desc.name = id->name;
 408         tps->desc.id = 0;
 409         tps->desc.ops = &tps62360_dcdc_ops;
 410         tps->desc.type = REGULATOR_VOLTAGE;
 411         tps->desc.owner = THIS_MODULE;
 412         tps->desc.min_uV = tps->voltage_base;
 413         tps->desc.uV_step = 10000;
 414
 415         tps->regmap = devm_regmap_init_i2c(client, &tps62360_regmap_config);
 416         if (IS_ERR(tps->regmap)) {
 417                 ret = PTR_ERR(tps->regmap);
 418                 dev_err(&client->dev,
 419                         "%s(): regmap allocation failed with err %d\n",
 420                         __func__, ret);
 421                 return ret;
 422         }
 423         i2c_set_clientdata(client, tps);
 424
 425         tps->curr_vset_id = (pdata->vsel1_def_state & 1) * 2 +
 426                                 (pdata->vsel0_def_state & 1);
 427         tps->lru_index[0] = tps->curr_vset_id;
 428         tps->valid_gpios = false;
 429
 430         if (gpio_is_valid(tps->vsel0_gpio) && gpio_is_valid(tps->vsel1_gpio)) {
 431                 int gpio_flags;
 432                 gpio_flags = (pdata->vsel0_def_state) ?
 433                                 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
 434                 ret = gpio_request_one(tps->vsel0_gpio,
 435                                 gpio_flags, "tps62360-vsel0");
 436                 if (ret) {
 437                         dev_err(&client->dev,
 438                                 "%s(): Could not obtain vsel0 GPIO %d: %d\n",
 439                                 __func__, tps->vsel0_gpio, ret);
 440                         goto err_gpio0;
 441                 }
 442
 443                 gpio_flags = (pdata->vsel1_def_state) ?
 444                                 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
 445                 ret = gpio_request_one(tps->vsel1_gpio,
 446                                 gpio_flags, "tps62360-vsel1");
 447                 if (ret) {
 448                         dev_err(&client->dev,
 449                                 "%s(): Could not obtain vsel1 GPIO %d: %d\n",
 450                                 __func__, tps->vsel1_gpio, ret);
 451                         goto err_gpio1;
 452                 }
 453                 tps->valid_gpios = true;
 454
 455                 /*
 456                  * Initialize the lru index with vset_reg id
 457                  * The index 0 will be most recently used and
 458                  * set with the tps->curr_vset_id */
 459                 for (i = 0; i < 4; ++i)
 460                         tps->lru_index[i] = i;
 461                 tps->lru_index[0] = tps->curr_vset_id;
 462                 tps->lru_index[tps->curr_vset_id] = 0;
 463         }
 464
 465         ret = tps62360_init_dcdc(tps, pdata);
 466         if (ret < 0) {
 467                 dev_err(tps->dev, "%s(): Init failed with err = %d\n",
 468                                 __func__, ret);
 469                 goto err_init;
 470         }
 471
 472         config.dev = &client->dev;
 473         config.init_data = pdata->reg_init_data;
 474         config.driver_data = tps;
 475
 476         /* Register the regulators */
 477         rdev = regulator_register(&tps->desc, &config);
 478         if (IS_ERR(rdev)) {
 479                 dev_err(tps->dev,
 480                         "%s(): regulator register failed with err %s\n",
 481                         __func__, id->name);
 482                 ret = PTR_ERR(rdev);
 483                 goto err_init;
 484         }
 485
 486         tps->rdev = rdev;
 487         return 0;
 488
 489 err_init:
 490         if (gpio_is_valid(tps->vsel1_gpio))
 491                 gpio_free(tps->vsel1_gpio);
 492 err_gpio1:
 493         if (gpio_is_valid(tps->vsel0_gpio))
 494                 gpio_free(tps->vsel0_gpio);
 495 err_gpio0:
 496         return ret;
 497 }
 498
 499 /**
 500  * tps62360_remove - tps62360 driver i2c remove handler
 501  * @client: i2c driver client device structure
 502  *
 503  * Unregister TPS driver as an i2c client device driver
 504  */
 505 static int __devexit tps62360_remove(struct i2c_client *client)
 506 {
 507         struct tps62360_chip *tps = i2c_get_clientdata(client);
 508
 509         if (gpio_is_valid(tps->vsel1_gpio))
 510                 gpio_free(tps->vsel1_gpio);
 511
 512         if (gpio_is_valid(tps->vsel0_gpio))
 513                 gpio_free(tps->vsel0_gpio);
 514
 515         regulator_unregister(tps->rdev);
 516         return 0;
 517 }
 518
 519 static void tps62360_shutdown(struct i2c_client *client)
 520 {
 521         struct tps62360_chip *tps = i2c_get_clientdata(client);
 522         int st;
 523
 524         if (!tps->en_discharge)
 525                 return;
 526
 527         /* Configure the output discharge path */
 528         st = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), BIT(2));
 529         if (st < 0)
 530                 dev_err(tps->dev,
 531                         "%s(): register %d update failed with err %d\n",
 532                         __func__, REG_RAMPCTRL, st);
 533 }
 534
 535 static const struct i2c_device_id tps62360_id[] = {
 536         {.name = "tps62360", .driver_data = TPS62360},
 537         {.name = "tps62361", .driver_data = TPS62361},
 538         {.name = "tps62362", .driver_data = TPS62362},
 539         {.name = "tps62363", .driver_data = TPS62363},
 540         {},
 541 };
 542
 543 MODULE_DEVICE_TABLE(i2c, tps62360_id);
 544
 545 static struct i2c_driver tps62360_i2c_driver = {
 546         .driver = {
 547                 .name = "tps62360",
 548                 .owner = THIS_MODULE,
 549                 .of_match_table = of_match_ptr(tps62360_of_match),
 550         },
 551         .probe = tps62360_probe,
 552         .remove = __devexit_p(tps62360_remove),
 553         .shutdown = tps62360_shutdown,
 554         .id_table = tps62360_id,
 555 };
 556
 557 static int __init tps62360_init(void)
 558 {
 559         return i2c_add_driver(&tps62360_i2c_driver);
 560 }
 561 subsys_initcall(tps62360_init);
 562
 563 static void __exit tps62360_cleanup(void)
 564 {
 565         i2c_del_driver(&tps62360_i2c_driver);
 566 }
 567 module_exit(tps62360_cleanup);
 568
 569 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 570 MODULE_DESCRIPTION("TPS6236x voltage regulator driver");
 571 MODULE_LICENSE("GPL v2");