drivers/regulator/mcp16502.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // MCP16502 PMIC driver
   4 //
   5 // Copyright (C) 2018 Microchip Technology Inc. and its subsidiaries
   6 //
   7 // Author: Andrei Stefanescu <andrei.stefanescu@microchip.com>
   8 //
   9 // Inspired from tps65086-regulator.c
  10
  11 #include <linux/gpio.h>
  12 #include <linux/i2c.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/of.h>
  17 #include <linux/regmap.h>
  18 #include <linux/regulator/driver.h>
  19 #include <linux/suspend.h>
  20 #include <linux/gpio/consumer.h>
  21
  22 #define VDD_LOW_SEL 0x0D
  23 #define VDD_HIGH_SEL 0x3F
  24
  25 #define MCP16502_FLT BIT(7)
  26 #define MCP16502_ENS BIT(0)
  27
  28 /*
  29  * The PMIC has four sets of registers corresponding to four power modes:
  30  * Performance, Active, Low-power, Hibernate.
  31  *
  32  * Registers:
  33  * Each regulator has a register for each power mode. To access a register
  34  * for a specific regulator and mode BASE_* and OFFSET_* need to be added.
  35  *
  36  * Operating modes:
  37  * In order for the PMIC to transition to operating modes it has to be
  38  * controlled via GPIO lines called LPM and HPM.
  39  *
  40  * The registers are fully configurable such that you can put all regulators in
  41  * a low-power state while the PMIC is in Active mode. They are supposed to be
  42  * configured at startup and then simply transition to/from a global low-power
  43  * state by setting the GPIO lpm pin high/low.
  44  *
  45  * This driver keeps the PMIC in Active mode, Low-power state is set for the
  46  * regulators by enabling/disabling operating mode (FPWM or Auto PFM).
  47  *
  48  * The PMIC's Low-power and Hibernate modes are used during standby/suspend.
  49  * To enter standby/suspend the PMIC will go to Low-power mode. From there, it
  50  * will transition to Hibernate when the PWRHLD line is set to low by the MPU.
  51  */
  52
  53 /*
  54  * This function is useful for iterating over all regulators and accessing their
  55  * registers in a generic way or accessing a regulator device by its id.
  56  */
  57 #define MCP16502_BASE(i) (((i) + 1) << 4)
  58 #define MCP16502_STAT_BASE(i) ((i) + 5)
  59
  60 #define MCP16502_OFFSET_MODE_A 0
  61 #define MCP16502_OFFSET_MODE_LPM 1
  62 #define MCP16502_OFFSET_MODE_HIB 2
  63
  64 #define MCP16502_OPMODE_ACTIVE REGULATOR_MODE_NORMAL
  65 #define MCP16502_OPMODE_LPM REGULATOR_MODE_IDLE
  66 #define MCP16502_OPMODE_HIB REGULATOR_MODE_STANDBY
  67
  68 #define MCP16502_MODE_AUTO_PFM 0
  69 #define MCP16502_MODE_FPWM BIT(6)
  70
  71 #define MCP16502_VSEL 0x3F
  72 #define MCP16502_EN BIT(7)
  73 #define MCP16502_MODE BIT(6)
  74
  75 #define MCP16502_MIN_REG 0x0
  76 #define MCP16502_MAX_REG 0x65
  77
  78 static unsigned int mcp16502_of_map_mode(unsigned int mode)
  79 {
  80         if (mode == REGULATOR_MODE_NORMAL || mode == REGULATOR_MODE_IDLE)
  81                 return mode;
  82
  83         return REGULATOR_MODE_INVALID;
  84 }
  85
  86 #define MCP16502_REGULATOR(_name, _id, _ranges, _ops)                   \
  87         [_id] = {                                                       \
  88                 .name                   = _name,                        \
  89                 .regulators_node        = of_match_ptr("regulators"),   \
  90                 .id                     = _id,                          \
  91                 .ops                    = &(_ops),                      \
  92                 .type                   = REGULATOR_VOLTAGE,            \
  93                 .owner                  = THIS_MODULE,                  \
  94                 .n_voltages             = MCP16502_VSEL + 1,            \
  95                 .linear_ranges          = _ranges,                      \
  96                 .n_linear_ranges        = ARRAY_SIZE(_ranges),          \
  97                 .of_match               = of_match_ptr(_name),          \
  98                 .of_map_mode            = mcp16502_of_map_mode,         \
  99                 .vsel_reg               = (((_id) + 1) << 4),           \
 100                 .vsel_mask              = MCP16502_VSEL,                \
 101                 .enable_reg             = (((_id) + 1) << 4),           \
 102                 .enable_mask            = MCP16502_EN,                  \
 103         }
 104
 105 enum {
 106         BUCK1 = 0,
 107         BUCK2,
 108         BUCK3,
 109         BUCK4,
 110         LDO1,
 111         LDO2,
 112         NUM_REGULATORS
 113 };
 114
 115 /*
 116  * struct mcp16502 - PMIC representation
 117  * @rdev: the regulators belonging to this chip
 118  * @rmap: regmap to be used for I2C communication
 119  * @lpm: LPM GPIO descriptor
 120  */
 121 struct mcp16502 {
 122         struct regulator_dev *rdev[NUM_REGULATORS];
 123         struct regmap *rmap;
 124         struct gpio_desc *lpm;
 125 };
 126
 127 /*
 128  * mcp16502_gpio_set_mode() - set the GPIO corresponding value
 129  *
 130  * Used to prepare transitioning into hibernate or resuming from it.
 131  */
 132 static void mcp16502_gpio_set_mode(struct mcp16502 *mcp, int mode)
 133 {
 134         switch (mode) {
 135         case MCP16502_OPMODE_ACTIVE:
 136                 gpiod_set_value(mcp->lpm, 0);
 137                 break;
 138         case MCP16502_OPMODE_LPM:
 139         case MCP16502_OPMODE_HIB:
 140                 gpiod_set_value(mcp->lpm, 1);
 141                 break;
 142         default:
 143                 pr_err("%s: %d invalid\n", __func__, mode);
 144         }
 145 }
 146
 147 /*
 148  * mcp16502_get_reg() - get the PMIC's configuration register for opmode
 149  *
 150  * @rdev: the regulator whose register we are searching
 151  * @opmode: the PMIC's operating mode ACTIVE, Low-power, Hibernate
 152  */
 153 static int mcp16502_get_reg(struct regulator_dev *rdev, int opmode)
 154 {
 155         int reg = MCP16502_BASE(rdev_get_id(rdev));
 156
 157         switch (opmode) {
 158         case MCP16502_OPMODE_ACTIVE:
 159                 return reg + MCP16502_OFFSET_MODE_A;
 160         case MCP16502_OPMODE_LPM:
 161                 return reg + MCP16502_OFFSET_MODE_LPM;
 162         case MCP16502_OPMODE_HIB:
 163                 return reg + MCP16502_OFFSET_MODE_HIB;
 164         default:
 165                 return -EINVAL;
 166         }
 167 }
 168
 169 /*
 170  * mcp16502_get_mode() - return the current operating mode of a regulator
 171  *
 172  * Note: all functions that are not part of entering/exiting standby/suspend
 173  *       use the Active mode registers.
 174  *
 175  * Note: this is different from the PMIC's operatig mode, it is the
 176  *       MODE bit from the regulator's register.
 177  */
 178 static unsigned int mcp16502_get_mode(struct regulator_dev *rdev)
 179 {
 180         unsigned int val;
 181         int ret, reg;
 182         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 183
 184         reg = mcp16502_get_reg(rdev, MCP16502_OPMODE_ACTIVE);
 185         if (reg < 0)
 186                 return reg;
 187
 188         ret = regmap_read(mcp->rmap, reg, &val);
 189         if (ret)
 190                 return ret;
 191
 192         switch (val & MCP16502_MODE) {
 193         case MCP16502_MODE_FPWM:
 194                 return REGULATOR_MODE_NORMAL;
 195         case MCP16502_MODE_AUTO_PFM:
 196                 return REGULATOR_MODE_IDLE;
 197         default:
 198                 return REGULATOR_MODE_INVALID;
 199         }
 200 }
 201
 202 /*
 203  * _mcp16502_set_mode() - helper for set_mode and set_suspend_mode
 204  *
 205  * @rdev: the regulator for which we are setting the mode
 206  * @mode: the regulator's mode (the one from MODE bit)
 207  * @opmode: the PMIC's operating mode: Active/Low-power/Hibernate
 208  */
 209 static int _mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode,
 210                               unsigned int op_mode)
 211 {
 212         int val;
 213         int reg;
 214         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 215
 216         reg = mcp16502_get_reg(rdev, op_mode);
 217         if (reg < 0)
 218                 return reg;
 219
 220         switch (mode) {
 221         case REGULATOR_MODE_NORMAL:
 222                 val = MCP16502_MODE_FPWM;
 223                 break;
 224         case REGULATOR_MODE_IDLE:
 225                 val = MCP16502_MODE_AUTO_PFM;
 226                 break;
 227         default:
 228                 return -EINVAL;
 229         }
 230
 231         reg = regmap_update_bits(mcp->rmap, reg, MCP16502_MODE, val);
 232         return reg;
 233 }
 234
 235 /*
 236  * mcp16502_set_mode() - regulator_ops set_mode
 237  */
 238 static int mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode)
 239 {
 240         return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_ACTIVE);
 241 }
 242
 243 /*
 244  * mcp16502_get_status() - regulator_ops get_status
 245  */
 246 static int mcp16502_get_status(struct regulator_dev *rdev)
 247 {
 248         int ret;
 249         unsigned int val;
 250         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 251
 252         ret = regmap_read(mcp->rmap, MCP16502_STAT_BASE(rdev_get_id(rdev)),
 253                           &val);
 254         if (ret)
 255                 return ret;
 256
 257         if (val & MCP16502_FLT)
 258                 return REGULATOR_STATUS_ERROR;
 259         else if (val & MCP16502_ENS)
 260                 return REGULATOR_STATUS_ON;
 261         else if (!(val & MCP16502_ENS))
 262                 return REGULATOR_STATUS_OFF;
 263
 264         return REGULATOR_STATUS_UNDEFINED;
 265 }
 266
 267 #ifdef CONFIG_SUSPEND
 268 /*
 269  * mcp16502_suspend_get_target_reg() - get the reg of the target suspend PMIC
 270  *                                     mode
 271  */
 272 static int mcp16502_suspend_get_target_reg(struct regulator_dev *rdev)
 273 {
 274         switch (pm_suspend_target_state) {
 275         case PM_SUSPEND_STANDBY:
 276                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_LPM);
 277         case PM_SUSPEND_ON:
 278         case PM_SUSPEND_MEM:
 279                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_HIB);
 280         default:
 281                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 282                         pm_suspend_target_state);
 283         }
 284
 285         return -EINVAL;
 286 }
 287
 288 /*
 289  * mcp16502_set_suspend_voltage() - regulator_ops set_suspend_voltage
 290  */
 291 static int mcp16502_set_suspend_voltage(struct regulator_dev *rdev, int uV)
 292 {
 293         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 294         int sel = regulator_map_voltage_linear_range(rdev, uV, uV);
 295         int reg = mcp16502_suspend_get_target_reg(rdev);
 296
 297         if (sel < 0)
 298                 return sel;
 299
 300         if (reg < 0)
 301                 return reg;
 302
 303         return regmap_update_bits(mcp->rmap, reg, MCP16502_VSEL, sel);
 304 }
 305
 306 /*
 307  * mcp16502_set_suspend_mode() - regulator_ops set_suspend_mode
 308  */
 309 static int mcp16502_set_suspend_mode(struct regulator_dev *rdev,
 310                                      unsigned int mode)
 311 {
 312         switch (pm_suspend_target_state) {
 313         case PM_SUSPEND_STANDBY:
 314                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_LPM);
 315         case PM_SUSPEND_ON:
 316         case PM_SUSPEND_MEM:
 317                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_HIB);
 318         default:
 319                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 320                         pm_suspend_target_state);
 321         }
 322
 323         return -EINVAL;
 324 }
 325
 326 /*
 327  * mcp16502_set_suspend_enable() - regulator_ops set_suspend_enable
 328  */
 329 static int mcp16502_set_suspend_enable(struct regulator_dev *rdev)
 330 {
 331         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 332         int reg = mcp16502_suspend_get_target_reg(rdev);
 333
 334         if (reg < 0)
 335                 return reg;
 336
 337         return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, MCP16502_EN);
 338 }
 339
 340 /*
 341  * mcp16502_set_suspend_disable() - regulator_ops set_suspend_disable
 342  */
 343 static int mcp16502_set_suspend_disable(struct regulator_dev *rdev)
 344 {
 345         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 346         int reg = mcp16502_suspend_get_target_reg(rdev);
 347
 348         if (reg < 0)
 349                 return reg;
 350
 351         return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, 0);
 352 }
 353 #endif /* CONFIG_SUSPEND */
 354
 355 static const struct regulator_ops mcp16502_buck_ops = {
 356         .list_voltage                   = regulator_list_voltage_linear_range,
 357         .map_voltage                    = regulator_map_voltage_linear_range,
 358         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 359         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 360         .enable                         = regulator_enable_regmap,
 361         .disable                        = regulator_disable_regmap,
 362         .is_enabled                     = regulator_is_enabled_regmap,
 363         .get_status                     = mcp16502_get_status,
 364
 365         .set_mode                       = mcp16502_set_mode,
 366         .get_mode                       = mcp16502_get_mode,
 367
 368 #ifdef CONFIG_SUSPEND
 369         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 370         .set_suspend_mode               = mcp16502_set_suspend_mode,
 371         .set_suspend_enable             = mcp16502_set_suspend_enable,
 372         .set_suspend_disable            = mcp16502_set_suspend_disable,
 373 #endif /* CONFIG_SUSPEND */
 374 };
 375
 376 /*
 377  * LDOs cannot change operating modes.
 378  */
 379 static const struct regulator_ops mcp16502_ldo_ops = {
 380         .list_voltage                   = regulator_list_voltage_linear_range,
 381         .map_voltage                    = regulator_map_voltage_linear_range,
 382         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 383         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 384         .enable                         = regulator_enable_regmap,
 385         .disable                        = regulator_disable_regmap,
 386         .is_enabled                     = regulator_is_enabled_regmap,
 387         .get_status                     = mcp16502_get_status,
 388
 389 #ifdef CONFIG_SUSPEND
 390         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 391         .set_suspend_enable             = mcp16502_set_suspend_enable,
 392         .set_suspend_disable            = mcp16502_set_suspend_disable,
 393 #endif /* CONFIG_SUSPEND */
 394 };
 395
 396 static const struct of_device_id mcp16502_ids[] = {
 397         { .compatible = "microchip,mcp16502", },
 398         {}
 399 };
 400 MODULE_DEVICE_TABLE(of, mcp16502_ids);
 401
 402 static const struct regulator_linear_range b1l12_ranges[] = {
 403         REGULATOR_LINEAR_RANGE(1200000, VDD_LOW_SEL, VDD_HIGH_SEL, 50000),
 404 };
 405
 406 static const struct regulator_linear_range b234_ranges[] = {
 407         REGULATOR_LINEAR_RANGE(600000, VDD_LOW_SEL, VDD_HIGH_SEL, 25000),
 408 };
 409
 410 static const struct regulator_desc mcp16502_desc[] = {
 411         /* MCP16502_REGULATOR(_name, _id, ranges, regulator_ops) */
 412         MCP16502_REGULATOR("VDD_IO", BUCK1, b1l12_ranges, mcp16502_buck_ops),
 413         MCP16502_REGULATOR("VDD_DDR", BUCK2, b234_ranges, mcp16502_buck_ops),
 414         MCP16502_REGULATOR("VDD_CORE", BUCK3, b234_ranges, mcp16502_buck_ops),
 415         MCP16502_REGULATOR("VDD_OTHER", BUCK4, b234_ranges, mcp16502_buck_ops),
 416         MCP16502_REGULATOR("LDO1", LDO1, b1l12_ranges, mcp16502_ldo_ops),
 417         MCP16502_REGULATOR("LDO2", LDO2, b1l12_ranges, mcp16502_ldo_ops)
 418 };
 419
 420 static const struct regmap_range mcp16502_ranges[] = {
 421         regmap_reg_range(MCP16502_MIN_REG, MCP16502_MAX_REG)
 422 };
 423
 424 static const struct regmap_access_table mcp16502_yes_reg_table = {
 425         .yes_ranges = mcp16502_ranges,
 426         .n_yes_ranges = ARRAY_SIZE(mcp16502_ranges),
 427 };
 428
 429 static const struct regmap_config mcp16502_regmap_config = {
 430         .reg_bits       = 8,
 431         .val_bits       = 8,
 432         .max_register   = MCP16502_MAX_REG,
 433         .cache_type     = REGCACHE_NONE,
 434         .rd_table       = &mcp16502_yes_reg_table,
 435         .wr_table       = &mcp16502_yes_reg_table,
 436 };
 437
 438 /*
 439  * set_up_regulators() - initialize all regulators
 440  */
 441 static int setup_regulators(struct mcp16502 *mcp, struct device *dev,
 442                             struct regulator_config config)
 443 {
 444         int i;
 445
 446         for (i = 0; i < NUM_REGULATORS; i++) {
 447                 mcp->rdev[i] = devm_regulator_register(dev,
 448                                                        &mcp16502_desc[i],
 449                                                        &config);
 450                 if (IS_ERR(mcp->rdev[i])) {
 451                         dev_err(dev,
 452                                 "failed to register %s regulator %ld\n",
 453                                 mcp16502_desc[i].name, PTR_ERR(mcp->rdev[i]));
 454                         return PTR_ERR(mcp->rdev[i]);
 455                 }
 456         }
 457
 458         return 0;
 459 }
 460
 461 static int mcp16502_probe(struct i2c_client *client,
 462                           const struct i2c_device_id *id)
 463 {
 464         struct regulator_config config = { };
 465         struct device *dev;
 466         struct mcp16502 *mcp;
 467         int ret = 0;
 468
 469         dev = &client->dev;
 470         config.dev = dev;
 471
 472         mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
 473         if (!mcp)
 474                 return -ENOMEM;
 475
 476         mcp->rmap = devm_regmap_init_i2c(client, &mcp16502_regmap_config);
 477         if (IS_ERR(mcp->rmap)) {
 478                 ret = PTR_ERR(mcp->rmap);
 479                 dev_err(dev, "regmap init failed: %d\n", ret);
 480                 return ret;
 481         }
 482
 483         i2c_set_clientdata(client, mcp);
 484         config.regmap = mcp->rmap;
 485         config.driver_data = mcp;
 486
 487         mcp->lpm = devm_gpiod_get(dev, "lpm", GPIOD_OUT_LOW);
 488         if (IS_ERR(mcp->lpm)) {
 489                 dev_err(dev, "failed to get lpm pin: %ld\n", PTR_ERR(mcp->lpm));
 490                 return PTR_ERR(mcp->lpm);
 491         }
 492
 493         ret = setup_regulators(mcp, dev, config);
 494         if (ret != 0)
 495                 return ret;
 496
 497         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 498
 499         return 0;
 500 }
 501
 502 #ifdef CONFIG_PM_SLEEP
 503 static int mcp16502_suspend_noirq(struct device *dev)
 504 {
 505         struct i2c_client *client = to_i2c_client(dev);
 506         struct mcp16502 *mcp = i2c_get_clientdata(client);
 507
 508         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_LPM);
 509
 510         return 0;
 511 }
 512
 513 static int mcp16502_resume_noirq(struct device *dev)
 514 {
 515         struct i2c_client *client = to_i2c_client(dev);
 516         struct mcp16502 *mcp = i2c_get_clientdata(client);
 517
 518         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 519
 520         return 0;
 521 }
 522 #endif
 523
 524 #ifdef CONFIG_PM
 525 static const struct dev_pm_ops mcp16502_pm_ops = {
 526         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mcp16502_suspend_noirq,
 527                                       mcp16502_resume_noirq)
 528 };
 529 #endif
 530 static const struct i2c_device_id mcp16502_i2c_id[] = {
 531         { "mcp16502", 0 },
 532         { }
 533 };
 534 MODULE_DEVICE_TABLE(i2c, mcp16502_i2c_id);
 535
 536 static struct i2c_driver mcp16502_drv = {
 537         .probe          = mcp16502_probe,
 538         .driver         = {
 539                 .name   = "mcp16502-regulator",
 540                 .of_match_table = of_match_ptr(mcp16502_ids),
 541 #ifdef CONFIG_PM
 542                 .pm = &mcp16502_pm_ops,
 543 #endif
 544         },
 545         .id_table       = mcp16502_i2c_id,
 546 };
 547
 548 module_i2c_driver(mcp16502_drv);
 549
 550 MODULE_LICENSE("GPL v2");
 551 MODULE_DESCRIPTION("MCP16502 PMIC driver");
 552 MODULE_AUTHOR("Andrei Stefanescu andrei.stefanescu@microchip.com");