drivers/regulator/tps65090-regulator.c

   1 /*
   2  * Regulator driver for tps65090 power management chip.
   3  *
   4  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
   5
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9
  10  * This program is distributed in the hope 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
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/delay.h>
  21 #include <linux/init.h>
  22 #include <linux/gpio.h>
  23 #include <linux/of_gpio.h>
  24 #include <linux/slab.h>
  25 #include <linux/err.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/regulator/driver.h>
  28 #include <linux/regulator/machine.h>
  29 #include <linux/regulator/of_regulator.h>
  30 #include <linux/mfd/tps65090.h>
  31
  32 #define MAX_CTRL_READ_TRIES     5
  33 #define MAX_FET_ENABLE_TRIES    1000
  34
  35 #define CTRL_EN_BIT             0 /* Regulator enable bit, active high */
  36 #define CTRL_WT_BIT             2 /* Regulator wait time 0 bit */
  37 #define CTRL_PG_BIT             4 /* Regulator power good bit, 1=good */
  38 #define CTRL_TO_BIT             7 /* Regulator timeout bit, 1=wait */
  39
  40 #define MAX_OVERCURRENT_WAIT    3 /* Overcurrent wait must be <= this */
  41
  42 /**
  43  * struct tps65090_regulator - Per-regulator data for a tps65090 regulator
  44  *
  45  * @dev: Pointer to our device.
  46  * @desc: The struct regulator_desc for the regulator.
  47  * @rdev: The struct regulator_dev for the regulator.
  48  * @overcurrent_wait_valid: True if overcurrent_wait is valid.
  49  * @overcurrent_wait: For FETs, the value to put in the WTFET bitfield.
  50  */
  51
  52 struct tps65090_regulator {
  53         struct device           *dev;
  54         struct regulator_desc   *desc;
  55         struct regulator_dev    *rdev;
  56         bool                    overcurrent_wait_valid;
  57         int                     overcurrent_wait;
  58 };
  59
  60 static struct regulator_ops tps65090_ext_control_ops = {
  61 };
  62
  63 /**
  64  * tps65090_reg_set_overcurrent_wait - Setup overcurrent wait
  65  *
  66  * This will set the overcurrent wait time based on what's in the regulator
  67  * info.
  68  *
  69  * @ri:         Overall regulator data
  70  * @rdev:       Regulator device
  71  *
  72  * Return: 0 if no error, non-zero if there was an error writing the register.
  73  */
  74 static int tps65090_reg_set_overcurrent_wait(struct tps65090_regulator *ri,
  75                                              struct regulator_dev *rdev)
  76 {
  77         int ret;
  78
  79         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  80                                  MAX_OVERCURRENT_WAIT << CTRL_WT_BIT,
  81                                  ri->overcurrent_wait << CTRL_WT_BIT);
  82         if (ret) {
  83                 dev_err(&rdev->dev, "Error updating overcurrent wait %#x\n",
  84                         rdev->desc->enable_reg);
  85         }
  86
  87         return ret;
  88 }
  89
  90 /**
  91  * tps65090_try_enable_fet - Try to enable a FET
  92  *
  93  * @rdev:       Regulator device
  94  *
  95  * Return: 0 if ok, -ENOTRECOVERABLE if the FET power good bit did not get
  96  * set, or some other -ve value if another error occurred (e.g. i2c error)
  97  */
  98 static int tps65090_try_enable_fet(struct regulator_dev *rdev)
  99 {
 100         unsigned int control;
 101         int ret, i;
 102
 103         ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 104                                  rdev->desc->enable_mask,
 105                                  rdev->desc->enable_mask);
 106         if (ret < 0) {
 107                 dev_err(&rdev->dev, "Error in updating reg %#x\n",
 108                         rdev->desc->enable_reg);
 109                 return ret;
 110         }
 111
 112         for (i = 0; i < MAX_CTRL_READ_TRIES; i++) {
 113                 ret = regmap_read(rdev->regmap, rdev->desc->enable_reg,
 114                                   &control);
 115                 if (ret < 0)
 116                         return ret;
 117
 118                 if (!(control & BIT(CTRL_TO_BIT)))
 119                         break;
 120
 121                 usleep_range(1000, 1500);
 122         }
 123         if (!(control & BIT(CTRL_PG_BIT)))
 124                 return -ENOTRECOVERABLE;
 125
 126         return 0;
 127 }
 128
 129 /**
 130  * tps65090_fet_enable - Enable a FET, trying a few times if it fails
 131  *
 132  * Some versions of the tps65090 have issues when turning on the FETs.
 133  * This function goes through several steps to ensure the best chance of the
 134  * FET going on.  Specifically:
 135  * - We'll make sure that we bump the "overcurrent wait" to the maximum, which
 136  *   increases the chances that we'll turn on properly.
 137  * - We'll retry turning the FET on multiple times (turning off in between).
 138  *
 139  * @rdev:       Regulator device
 140  *
 141  * Return: 0 if ok, non-zero if it fails.
 142  */
 143 static int tps65090_fet_enable(struct regulator_dev *rdev)
 144 {
 145         int ret, tries;
 146
 147         /*
 148          * Try enabling multiple times until we succeed since sometimes the
 149          * first try times out.
 150          */
 151         tries = 0;
 152         while (true) {
 153                 ret = tps65090_try_enable_fet(rdev);
 154                 if (!ret)
 155                         break;
 156                 if (ret != -ENOTRECOVERABLE || tries == MAX_FET_ENABLE_TRIES)
 157                         goto err;
 158
 159                 /* Try turning the FET off (and then on again) */
 160                 ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 161                                          rdev->desc->enable_mask, 0);
 162                 if (ret)
 163                         goto err;
 164
 165                 tries++;
 166         }
 167
 168         if (tries)
 169                 dev_warn(&rdev->dev, "reg %#x enable ok after %d tries\n",
 170                          rdev->desc->enable_reg, tries);
 171
 172         return 0;
 173 err:
 174         dev_warn(&rdev->dev, "reg %#x enable failed\n", rdev->desc->enable_reg);
 175         WARN_ON(1);
 176
 177         return ret;
 178 }
 179
 180 static struct regulator_ops tps65090_reg_control_ops = {
 181         .enable         = regulator_enable_regmap,
 182         .disable        = regulator_disable_regmap,
 183         .is_enabled     = regulator_is_enabled_regmap,
 184 };
 185
 186 static struct regulator_ops tps65090_fet_control_ops = {
 187         .enable         = tps65090_fet_enable,
 188         .disable        = regulator_disable_regmap,
 189         .is_enabled     = regulator_is_enabled_regmap,
 190 };
 191
 192 static struct regulator_ops tps65090_ldo_ops = {
 193 };
 194
 195 #define tps65090_REG_DESC(_id, _sname, _en_reg, _en_bits, _ops) \
 196 {                                                       \
 197         .name = "TPS65090_RAILS"#_id,                   \
 198         .supply_name = _sname,                          \
 199         .id = TPS65090_REGULATOR_##_id,                 \
 200         .ops = &_ops,                                   \
 201         .enable_reg = _en_reg,                          \
 202         .enable_val = _en_bits,                         \
 203         .enable_mask = _en_bits,                        \
 204         .type = REGULATOR_VOLTAGE,                      \
 205         .owner = THIS_MODULE,                           \
 206 }
 207
 208 static struct regulator_desc tps65090_regulator_desc[] = {
 209         tps65090_REG_DESC(DCDC1, "vsys1",   0x0C, BIT(CTRL_EN_BIT),
 210                           tps65090_reg_control_ops),
 211         tps65090_REG_DESC(DCDC2, "vsys2",   0x0D, BIT(CTRL_EN_BIT),
 212                           tps65090_reg_control_ops),
 213         tps65090_REG_DESC(DCDC3, "vsys3",   0x0E, BIT(CTRL_EN_BIT),
 214                           tps65090_reg_control_ops),
 215
 216         tps65090_REG_DESC(FET1,  "infet1",  0x0F,
 217                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 218                           tps65090_fet_control_ops),
 219         tps65090_REG_DESC(FET2,  "infet2",  0x10,
 220                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 221                           tps65090_fet_control_ops),
 222         tps65090_REG_DESC(FET3,  "infet3",  0x11,
 223                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 224                           tps65090_fet_control_ops),
 225         tps65090_REG_DESC(FET4,  "infet4",  0x12,
 226                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 227                           tps65090_fet_control_ops),
 228         tps65090_REG_DESC(FET5,  "infet5",  0x13,
 229                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 230                           tps65090_fet_control_ops),
 231         tps65090_REG_DESC(FET6,  "infet6",  0x14,
 232                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 233                           tps65090_fet_control_ops),
 234         tps65090_REG_DESC(FET7,  "infet7",  0x15,
 235                           BIT(CTRL_EN_BIT) | BIT(CTRL_PG_BIT),
 236                           tps65090_fet_control_ops),
 237
 238         tps65090_REG_DESC(LDO1,  "vsys-l1", 0, 0,
 239                           tps65090_ldo_ops),
 240         tps65090_REG_DESC(LDO2,  "vsys-l2", 0, 0,
 241                           tps65090_ldo_ops),
 242 };
 243
 244 static inline bool is_dcdc(int id)
 245 {
 246         switch (id) {
 247         case TPS65090_REGULATOR_DCDC1:
 248         case TPS65090_REGULATOR_DCDC2:
 249         case TPS65090_REGULATOR_DCDC3:
 250                 return true;
 251         default:
 252                 return false;
 253         }
 254 }
 255
 256 static int tps65090_config_ext_control(
 257         struct tps65090_regulator *ri, bool enable)
 258 {
 259         int ret;
 260         struct device *parent = ri->dev->parent;
 261         unsigned int reg_en_reg = ri->desc->enable_reg;
 262
 263         if (enable)
 264                 ret = tps65090_set_bits(parent, reg_en_reg, 1);
 265         else
 266                 ret =  tps65090_clr_bits(parent, reg_en_reg, 1);
 267         if (ret < 0)
 268                 dev_err(ri->dev, "Error in updating reg 0x%x\n", reg_en_reg);
 269         return ret;
 270 }
 271
 272 static int tps65090_regulator_disable_ext_control(
 273                 struct tps65090_regulator *ri,
 274                 struct tps65090_regulator_plat_data *tps_pdata)
 275 {
 276         int ret = 0;
 277         struct device *parent = ri->dev->parent;
 278         unsigned int reg_en_reg = ri->desc->enable_reg;
 279
 280         /*
 281          * First enable output for internal control if require.
 282          * And then disable external control.
 283          */
 284         if (tps_pdata->reg_init_data->constraints.always_on ||
 285                         tps_pdata->reg_init_data->constraints.boot_on) {
 286                 ret =  tps65090_set_bits(parent, reg_en_reg, 0);
 287                 if (ret < 0) {
 288                         dev_err(ri->dev, "Error in set reg 0x%x\n", reg_en_reg);
 289                         return ret;
 290                 }
 291         }
 292         return tps65090_config_ext_control(ri, false);
 293 }
 294
 295 static void tps65090_configure_regulator_config(
 296                 struct tps65090_regulator_plat_data *tps_pdata,
 297                 struct regulator_config *config)
 298 {
 299         if (gpio_is_valid(tps_pdata->gpio)) {
 300                 int gpio_flag = GPIOF_OUT_INIT_LOW;
 301
 302                 if (tps_pdata->reg_init_data->constraints.always_on ||
 303                                 tps_pdata->reg_init_data->constraints.boot_on)
 304                         gpio_flag = GPIOF_OUT_INIT_HIGH;
 305
 306                 config->ena_gpio = tps_pdata->gpio;
 307                 config->ena_gpio_flags = gpio_flag;
 308         }
 309 }
 310
 311 #ifdef CONFIG_OF
 312 static struct of_regulator_match tps65090_matches[] = {
 313         { .name = "dcdc1", },
 314         { .name = "dcdc2", },
 315         { .name = "dcdc3", },
 316         { .name = "fet1",  },
 317         { .name = "fet2",  },
 318         { .name = "fet3",  },
 319         { .name = "fet4",  },
 320         { .name = "fet5",  },
 321         { .name = "fet6",  },
 322         { .name = "fet7",  },
 323         { .name = "ldo1",  },
 324         { .name = "ldo2",  },
 325 };
 326
 327 static struct tps65090_platform_data *tps65090_parse_dt_reg_data(
 328                 struct platform_device *pdev,
 329                 struct of_regulator_match **tps65090_reg_matches)
 330 {
 331         struct tps65090_platform_data *tps65090_pdata;
 332         struct device_node *np = pdev->dev.parent->of_node;
 333         struct device_node *regulators;
 334         int idx = 0, ret;
 335         struct tps65090_regulator_plat_data *reg_pdata;
 336
 337         tps65090_pdata = devm_kzalloc(&pdev->dev, sizeof(*tps65090_pdata),
 338                                 GFP_KERNEL);
 339         if (!tps65090_pdata)
 340                 return ERR_PTR(-ENOMEM);
 341
 342         reg_pdata = devm_kzalloc(&pdev->dev, TPS65090_REGULATOR_MAX *
 343                                 sizeof(*reg_pdata), GFP_KERNEL);
 344         if (!reg_pdata)
 345                 return ERR_PTR(-ENOMEM);
 346
 347         regulators = of_get_child_by_name(np, "regulators");
 348         if (!regulators) {
 349                 dev_err(&pdev->dev, "regulator node not found\n");
 350                 return ERR_PTR(-ENODEV);
 351         }
 352
 353         ret = of_regulator_match(&pdev->dev, regulators, tps65090_matches,
 354                         ARRAY_SIZE(tps65090_matches));
 355         of_node_put(regulators);
 356         if (ret < 0) {
 357                 dev_err(&pdev->dev,
 358                         "Error parsing regulator init data: %d\n", ret);
 359                 return ERR_PTR(ret);
 360         }
 361
 362         *tps65090_reg_matches = tps65090_matches;
 363         for (idx = 0; idx < ARRAY_SIZE(tps65090_matches); idx++) {
 364                 struct regulator_init_data *ri_data;
 365                 struct tps65090_regulator_plat_data *rpdata;
 366
 367                 rpdata = &reg_pdata[idx];
 368                 ri_data = tps65090_matches[idx].init_data;
 369                 if (!ri_data || !tps65090_matches[idx].of_node)
 370                         continue;
 371
 372                 rpdata->reg_init_data = ri_data;
 373                 rpdata->enable_ext_control = of_property_read_bool(
 374                                         tps65090_matches[idx].of_node,
 375                                         "ti,enable-ext-control");
 376                 if (rpdata->enable_ext_control)
 377                         rpdata->gpio = of_get_named_gpio(np,
 378                                         "dcdc-ext-control-gpios", 0);
 379
 380                 if (of_property_read_u32(tps65090_matches[idx].of_node,
 381                                          "ti,overcurrent-wait",
 382                                          &rpdata->overcurrent_wait) == 0)
 383                         rpdata->overcurrent_wait_valid = true;
 384
 385                 tps65090_pdata->reg_pdata[idx] = rpdata;
 386         }
 387         return tps65090_pdata;
 388 }
 389 #else
 390 static inline struct tps65090_platform_data *tps65090_parse_dt_reg_data(
 391                         struct platform_device *pdev,
 392                         struct of_regulator_match **tps65090_reg_matches)
 393 {
 394         *tps65090_reg_matches = NULL;
 395         return NULL;
 396 }
 397 #endif
 398
 399 static int tps65090_regulator_probe(struct platform_device *pdev)
 400 {
 401         struct tps65090 *tps65090_mfd = dev_get_drvdata(pdev->dev.parent);
 402         struct tps65090_regulator *ri = NULL;
 403         struct regulator_config config = { };
 404         struct regulator_dev *rdev;
 405         struct tps65090_regulator_plat_data *tps_pdata;
 406         struct tps65090_regulator *pmic;
 407         struct tps65090_platform_data *tps65090_pdata;
 408         struct of_regulator_match *tps65090_reg_matches = NULL;
 409         int num;
 410         int ret;
 411
 412         dev_dbg(&pdev->dev, "Probing regulator\n");
 413
 414         tps65090_pdata = dev_get_platdata(pdev->dev.parent);
 415         if (!tps65090_pdata && tps65090_mfd->dev->of_node)
 416                 tps65090_pdata = tps65090_parse_dt_reg_data(pdev,
 417                                         &tps65090_reg_matches);
 418         if (IS_ERR_OR_NULL(tps65090_pdata)) {
 419                 dev_err(&pdev->dev, "Platform data missing\n");
 420                 return tps65090_pdata ? PTR_ERR(tps65090_pdata) : -EINVAL;
 421         }
 422
 423         pmic = devm_kzalloc(&pdev->dev, TPS65090_REGULATOR_MAX * sizeof(*pmic),
 424                         GFP_KERNEL);
 425         if (!pmic)
 426                 return -ENOMEM;
 427
 428         for (num = 0; num < TPS65090_REGULATOR_MAX; num++) {
 429                 tps_pdata = tps65090_pdata->reg_pdata[num];
 430
 431                 ri = &pmic[num];
 432                 ri->dev = &pdev->dev;
 433                 ri->desc = &tps65090_regulator_desc[num];
 434                 ri->overcurrent_wait_valid = tps_pdata->overcurrent_wait_valid;
 435                 ri->overcurrent_wait = tps_pdata->overcurrent_wait;
 436
 437                 /*
 438                  * TPS5090 DCDC support the control from external digital input.
 439                  * Configure it as per platform data.
 440                  */
 441                 if (tps_pdata && is_dcdc(num) && tps_pdata->reg_init_data) {
 442                         if (tps_pdata->enable_ext_control) {
 443                                 tps65090_configure_regulator_config(
 444                                                 tps_pdata, &config);
 445                                 ri->desc->ops = &tps65090_ext_control_ops;
 446                         } else {
 447                                 ret = tps65090_regulator_disable_ext_control(
 448                                                 ri, tps_pdata);
 449                                 if (ret < 0) {
 450                                         dev_err(&pdev->dev,
 451                                                 "failed disable ext control\n");
 452                                         return ret;
 453                                 }
 454                         }
 455                 }
 456
 457                 config.dev = pdev->dev.parent;
 458                 config.driver_data = ri;
 459                 config.regmap = tps65090_mfd->rmap;
 460                 if (tps_pdata)
 461                         config.init_data = tps_pdata->reg_init_data;
 462                 else
 463                         config.init_data = NULL;
 464                 if (tps65090_reg_matches)
 465                         config.of_node = tps65090_reg_matches[num].of_node;
 466                 else
 467                         config.of_node = NULL;
 468
 469                 rdev = devm_regulator_register(&pdev->dev, ri->desc, &config);
 470                 if (IS_ERR(rdev)) {
 471                         dev_err(&pdev->dev, "failed to register regulator %s\n",
 472                                 ri->desc->name);
 473                         return PTR_ERR(rdev);
 474                 }
 475                 ri->rdev = rdev;
 476
 477                 if (ri->overcurrent_wait_valid) {
 478                         ret = tps65090_reg_set_overcurrent_wait(ri, rdev);
 479                         if (ret < 0)
 480                                 return ret;
 481                 }
 482
 483                 /* Enable external control if it is require */
 484                 if (tps_pdata && is_dcdc(num) && tps_pdata->reg_init_data &&
 485                                 tps_pdata->enable_ext_control) {
 486                         ret = tps65090_config_ext_control(ri, true);
 487                         if (ret < 0)
 488                                 return ret;
 489                 }
 490         }
 491
 492         platform_set_drvdata(pdev, pmic);
 493         return 0;
 494 }
 495
 496 static struct platform_driver tps65090_regulator_driver = {
 497         .driver = {
 498                 .name   = "tps65090-pmic",
 499                 .owner  = THIS_MODULE,
 500         },
 501         .probe          = tps65090_regulator_probe,
 502 };
 503
 504 static int __init tps65090_regulator_init(void)
 505 {
 506         return platform_driver_register(&tps65090_regulator_driver);
 507 }
 508 subsys_initcall(tps65090_regulator_init);
 509
 510 static void __exit tps65090_regulator_exit(void)
 511 {
 512         platform_driver_unregister(&tps65090_regulator_driver);
 513 }
 514 module_exit(tps65090_regulator_exit);
 515
 516 MODULE_DESCRIPTION("tps65090 regulator driver");
 517 MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
 518 MODULE_LICENSE("GPL v2");
 519 MODULE_ALIAS("platform:tps65090-pmic");