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
  21 #define VDD_LOW_SEL 0x0D
  22 #define VDD_HIGH_SEL 0x3F
  23
  24 #define MCP16502_FLT BIT(7)
  25 #define MCP16502_ENS BIT(0)
  26
  27 /*
  28  * The PMIC has four sets of registers corresponding to four power modes:
  29  * Performance, Active, Low-power, Hibernate.
  30  *
  31  * Registers:
  32  * Each regulator has a register for each power mode. To access a register
  33  * for a specific regulator and mode BASE_* and OFFSET_* need to be added.
  34  *
  35  * Operating modes:
  36  * In order for the PMIC to transition to operating modes it has to be
  37  * controlled via GPIO lines called LPM and HPM.
  38  *
  39  * The registers are fully configurable such that you can put all regulators in
  40  * a low-power state while the PMIC is in Active mode. They are supposed to be
  41  * configured at startup and then simply transition to/from a global low-power
  42  * state by setting the GPIO lpm pin high/low.
  43  *
  44  * This driver keeps the PMIC in Active mode, Low-power state is set for the
  45  * regulators by enabling/disabling operating mode (FPWM or Auto PFM).
  46  *
  47  * The PMIC's Low-power and Hibernate modes are used during standby/suspend.
  48  * To enter standby/suspend the PMIC will go to Low-power mode. From there, it
  49  * will transition to Hibernate when the PWRHLD line is set to low by the MPU.
  50  */
  51
  52 /*
  53  * This function is useful for iterating over all regulators and accessing their
  54  * registers in a generic way or accessing a regulator device by its id.
  55  */
  56 #define MCP16502_BASE(i) (((i) + 1) << 4)
  57 #define MCP16502_STAT_BASE(i) ((i) + 5)
  58
  59 #define MCP16502_OFFSET_MODE_A 0
  60 #define MCP16502_OFFSET_MODE_LPM 1
  61 #define MCP16502_OFFSET_MODE_HIB 2
  62
  63 #define MCP16502_OPMODE_ACTIVE REGULATOR_MODE_NORMAL
  64 #define MCP16502_OPMODE_LPM REGULATOR_MODE_IDLE
  65 #define MCP16502_OPMODE_HIB REGULATOR_MODE_STANDBY
  66
  67 #define MCP16502_MODE_AUTO_PFM 0
  68 #define MCP16502_MODE_FPWM BIT(6)
  69
  70 #define MCP16502_VSEL 0x3F
  71 #define MCP16502_EN BIT(7)
  72 #define MCP16502_MODE BIT(6)
  73
  74 #define MCP16502_MIN_REG 0x0
  75 #define MCP16502_MAX_REG 0x65
  76
  77 static unsigned int mcp16502_of_map_mode(unsigned int mode)
  78 {
  79         if (mode == REGULATOR_MODE_NORMAL || mode == REGULATOR_MODE_IDLE)
  80                 return mode;
  81
  82         return REGULATOR_MODE_INVALID;
  83 }
  84
  85 #define MCP16502_REGULATOR(_name, _id, _ranges, _ops)                   \
  86         [_id] = {                                                       \
  87                 .name                   = _name,                        \
  88                 .regulators_node        = of_match_ptr("regulators"),   \
  89                 .id                     = _id,                          \
  90                 .ops                    = &(_ops),                      \
  91                 .type                   = REGULATOR_VOLTAGE,            \
  92                 .owner                  = THIS_MODULE,                  \
  93                 .n_voltages             = MCP16502_VSEL + 1,            \
  94                 .linear_ranges          = _ranges,                      \
  95                 .n_linear_ranges        = ARRAY_SIZE(_ranges),          \
  96                 .of_match               = of_match_ptr(_name),          \
  97                 .of_map_mode            = mcp16502_of_map_mode,         \
  98                 .vsel_reg               = (((_id) + 1) << 4),           \
  99                 .vsel_mask              = MCP16502_VSEL,                \
 100                 .enable_reg             = (((_id) + 1) << 4),           \
 101                 .enable_mask            = MCP16502_EN,                  \
 102         }
 103
 104 enum {
 105         BUCK1 = 0,
 106         BUCK2,
 107         BUCK3,
 108         BUCK4,
 109         LDO1,
 110         LDO2,
 111         NUM_REGULATORS
 112 };
 113
 114 /*
 115  * struct mcp16502 - PMIC representation
 116  * @rdev: the regulators belonging to this chip
 117  * @rmap: regmap to be used for I2C communication
 118  * @lpm: LPM GPIO descriptor
 119  */
 120 struct mcp16502 {
 121         struct regulator_dev *rdev[NUM_REGULATORS];
 122         struct regmap *rmap;
 123         struct gpio_desc *lpm;
 124 };
 125
 126 /*
 127  * mcp16502_gpio_set_mode() - set the GPIO corresponding value
 128  *
 129  * Used to prepare transitioning into hibernate or resuming from it.
 130  */
 131 static void mcp16502_gpio_set_mode(struct mcp16502 *mcp, int mode)
 132 {
 133         switch (mode) {
 134         case MCP16502_OPMODE_ACTIVE:
 135                 gpiod_set_value(mcp->lpm, 0);
 136                 break;
 137         case MCP16502_OPMODE_LPM:
 138         case MCP16502_OPMODE_HIB:
 139                 gpiod_set_value(mcp->lpm, 1);
 140                 break;
 141         default:
 142                 pr_err("%s: %d invalid\n", __func__, mode);
 143         }
 144 }
 145
 146 /*
 147  * mcp16502_get_reg() - get the PMIC's configuration register for opmode
 148  *
 149  * @rdev: the regulator whose register we are searching
 150  * @opmode: the PMIC's operating mode ACTIVE, Low-power, Hibernate
 151  */
 152 static int mcp16502_get_reg(struct regulator_dev *rdev, int opmode)
 153 {
 154         int reg = MCP16502_BASE(rdev_get_id(rdev));
 155
 156         switch (opmode) {
 157         case MCP16502_OPMODE_ACTIVE:
 158                 return reg + MCP16502_OFFSET_MODE_A;
 159         case MCP16502_OPMODE_LPM:
 160                 return reg + MCP16502_OFFSET_MODE_LPM;
 161         case MCP16502_OPMODE_HIB:
 162                 return reg + MCP16502_OFFSET_MODE_HIB;
 163         default:
 164                 return -EINVAL;
 165         }
 166 }
 167
 168 /*
 169  * mcp16502_get_mode() - return the current operating mode of a regulator
 170  *
 171  * Note: all functions that are not part of entering/exiting standby/suspend
 172  *       use the Active mode registers.
 173  *
 174  * Note: this is different from the PMIC's operatig mode, it is the
 175  *       MODE bit from the regulator's register.
 176  */
 177 static unsigned int mcp16502_get_mode(struct regulator_dev *rdev)
 178 {
 179         unsigned int val;
 180         int ret, reg;
 181         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 182
 183         reg = mcp16502_get_reg(rdev, MCP16502_OPMODE_ACTIVE);
 184         if (reg < 0)
 185                 return reg;
 186
 187         ret = regmap_read(mcp->rmap, reg, &val);
 188         if (ret)
 189                 return ret;
 190
 191         switch (val & MCP16502_MODE) {
 192         case MCP16502_MODE_FPWM:
 193                 return REGULATOR_MODE_NORMAL;
 194         case MCP16502_MODE_AUTO_PFM:
 195                 return REGULATOR_MODE_IDLE;
 196         default:
 197                 return REGULATOR_MODE_INVALID;
 198         }
 199 }
 200
 201 /*
 202  * _mcp16502_set_mode() - helper for set_mode and set_suspend_mode
 203  *
 204  * @rdev: the regulator for which we are setting the mode
 205  * @mode: the regulator's mode (the one from MODE bit)
 206  * @opmode: the PMIC's operating mode: Active/Low-power/Hibernate
 207  */
 208 static int _mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode,
 209                               unsigned int op_mode)
 210 {
 211         int val;
 212         int reg;
 213         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 214
 215         reg = mcp16502_get_reg(rdev, op_mode);
 216         if (reg < 0)
 217                 return reg;
 218
 219         switch (mode) {
 220         case REGULATOR_MODE_NORMAL:
 221                 val = MCP16502_MODE_FPWM;
 222                 break;
 223         case REGULATOR_MODE_IDLE:
 224                 val = MCP16502_MODE_AUTO_PFM;
 225                 break;
 226         default:
 227                 return -EINVAL;
 228         }
 229
 230         reg = regmap_update_bits(mcp->rmap, reg, MCP16502_MODE, val);
 231         return reg;
 232 }
 233
 234 /*
 235  * mcp16502_set_mode() - regulator_ops set_mode
 236  */
 237 static int mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode)
 238 {
 239         return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_ACTIVE);
 240 }
 241
 242 /*
 243  * mcp16502_get_status() - regulator_ops get_status
 244  */
 245 static int mcp16502_get_status(struct regulator_dev *rdev)
 246 {
 247         int ret;
 248         unsigned int val;
 249         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 250
 251         ret = regmap_read(mcp->rmap, MCP16502_STAT_BASE(rdev_get_id(rdev)),
 252                           &val);
 253         if (ret)
 254                 return ret;
 255
 256         if (val & MCP16502_FLT)
 257                 return REGULATOR_STATUS_ERROR;
 258         else if (val & MCP16502_ENS)
 259                 return REGULATOR_STATUS_ON;
 260         else if (!(val & MCP16502_ENS))
 261                 return REGULATOR_STATUS_OFF;
 262
 263         return REGULATOR_STATUS_UNDEFINED;
 264 }
 265
 266 #ifdef CONFIG_SUSPEND
 267 /*
 268  * mcp16502_suspend_get_target_reg() - get the reg of the target suspend PMIC
 269  *                                     mode
 270  */
 271 static int mcp16502_suspend_get_target_reg(struct regulator_dev *rdev)
 272 {
 273         switch (pm_suspend_target_state) {
 274         case PM_SUSPEND_STANDBY:
 275                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_LPM);
 276         case PM_SUSPEND_ON:
 277         case PM_SUSPEND_MEM:
 278                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_HIB);
 279         default:
 280                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 281                         pm_suspend_target_state);
 282         }
 283
 284         return -EINVAL;
 285 }
 286
 287 /*
 288  * mcp16502_set_suspend_voltage() - regulator_ops set_suspend_voltage
 289  */
 290 static int mcp16502_set_suspend_voltage(struct regulator_dev *rdev, int uV)
 291 {
 292         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 293         int sel = regulator_map_voltage_linear_range(rdev, uV, uV);
 294         int reg = mcp16502_suspend_get_target_reg(rdev);
 295
 296         if (sel < 0)
 297                 return sel;
 298
 299         if (reg < 0)
 300                 return reg;
 301
 302         return regmap_update_bits(mcp->rmap, reg, MCP16502_VSEL, sel);
 303 }
 304
 305 /*
 306  * mcp16502_set_suspend_mode() - regulator_ops set_suspend_mode
 307  */
 308 static int mcp16502_set_suspend_mode(struct regulator_dev *rdev,
 309                                      unsigned int mode)
 310 {
 311         switch (pm_suspend_target_state) {
 312         case PM_SUSPEND_STANDBY:
 313                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_LPM);
 314         case PM_SUSPEND_ON:
 315         case PM_SUSPEND_MEM:
 316                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_HIB);
 317         default:
 318                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 319                         pm_suspend_target_state);
 320         }
 321
 322         return -EINVAL;
 323 }
 324
 325 /*
 326  * mcp16502_set_suspend_enable() - regulator_ops set_suspend_enable
 327  */
 328 static int mcp16502_set_suspend_enable(struct regulator_dev *rdev)
 329 {
 330         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 331         int reg = mcp16502_suspend_get_target_reg(rdev);
 332
 333         if (reg < 0)
 334                 return reg;
 335
 336         return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, MCP16502_EN);
 337 }
 338
 339 /*
 340  * mcp16502_set_suspend_disable() - regulator_ops set_suspend_disable
 341  */
 342 static int mcp16502_set_suspend_disable(struct regulator_dev *rdev)
 343 {
 344         struct mcp16502 *mcp = rdev_get_drvdata(rdev);
 345         int reg = mcp16502_suspend_get_target_reg(rdev);
 346
 347         if (reg < 0)
 348                 return reg;
 349
 350         return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, 0);
 351 }
 352 #endif /* CONFIG_SUSPEND */
 353
 354 static const struct regulator_ops mcp16502_buck_ops = {
 355         .list_voltage                   = regulator_list_voltage_linear_range,
 356         .map_voltage                    = regulator_map_voltage_linear_range,
 357         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 358         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 359         .enable                         = regulator_enable_regmap,
 360         .disable                        = regulator_disable_regmap,
 361         .is_enabled                     = regulator_is_enabled_regmap,
 362         .get_status                     = mcp16502_get_status,
 363
 364         .set_mode                       = mcp16502_set_mode,
 365         .get_mode                       = mcp16502_get_mode,
 366
 367 #ifdef CONFIG_SUSPEND
 368         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 369         .set_suspend_mode               = mcp16502_set_suspend_mode,
 370         .set_suspend_enable             = mcp16502_set_suspend_enable,
 371         .set_suspend_disable            = mcp16502_set_suspend_disable,
 372 #endif /* CONFIG_SUSPEND */
 373 };
 374
 375 /*
 376  * LDOs cannot change operating modes.
 377  */
 378 static const struct regulator_ops mcp16502_ldo_ops = {
 379         .list_voltage                   = regulator_list_voltage_linear_range,
 380         .map_voltage                    = regulator_map_voltage_linear_range,
 381         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 382         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 383         .enable                         = regulator_enable_regmap,
 384         .disable                        = regulator_disable_regmap,
 385         .is_enabled                     = regulator_is_enabled_regmap,
 386         .get_status                     = mcp16502_get_status,
 387
 388 #ifdef CONFIG_SUSPEND
 389         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 390         .set_suspend_enable             = mcp16502_set_suspend_enable,
 391         .set_suspend_disable            = mcp16502_set_suspend_disable,
 392 #endif /* CONFIG_SUSPEND */
 393 };
 394
 395 static const struct of_device_id mcp16502_ids[] = {
 396         { .compatible = "microchip,mcp16502", },
 397         {}
 398 };
 399 MODULE_DEVICE_TABLE(of, mcp16502_ids);
 400
 401 static const struct regulator_linear_range b1l12_ranges[] = {
 402         REGULATOR_LINEAR_RANGE(1200000, VDD_LOW_SEL, VDD_HIGH_SEL, 50000),
 403 };
 404
 405 static const struct regulator_linear_range b234_ranges[] = {
 406         REGULATOR_LINEAR_RANGE(600000, VDD_LOW_SEL, VDD_HIGH_SEL, 25000),
 407 };
 408
 409 static const struct regulator_desc mcp16502_desc[] = {
 410         /* MCP16502_REGULATOR(_name, _id, ranges, regulator_ops) */
 411         MCP16502_REGULATOR("VDD_IO", BUCK1, b1l12_ranges, mcp16502_buck_ops),
 412         MCP16502_REGULATOR("VDD_DDR", BUCK2, b234_ranges, mcp16502_buck_ops),
 413         MCP16502_REGULATOR("VDD_CORE", BUCK3, b234_ranges, mcp16502_buck_ops),
 414         MCP16502_REGULATOR("VDD_OTHER", BUCK4, b234_ranges, mcp16502_buck_ops),
 415         MCP16502_REGULATOR("LDO1", LDO1, b1l12_ranges, mcp16502_ldo_ops),
 416         MCP16502_REGULATOR("LDO2", LDO2, b1l12_ranges, mcp16502_ldo_ops)
 417 };
 418
 419 static const struct regmap_range mcp16502_ranges[] = {
 420         regmap_reg_range(MCP16502_MIN_REG, MCP16502_MAX_REG)
 421 };
 422
 423 static const struct regmap_access_table mcp16502_yes_reg_table = {
 424         .yes_ranges = mcp16502_ranges,
 425         .n_yes_ranges = ARRAY_SIZE(mcp16502_ranges),
 426 };
 427
 428 static const struct regmap_config mcp16502_regmap_config = {
 429         .reg_bits       = 8,
 430         .val_bits       = 8,
 431         .max_register   = MCP16502_MAX_REG,
 432         .cache_type     = REGCACHE_NONE,
 433         .rd_table       = &mcp16502_yes_reg_table,
 434         .wr_table       = &mcp16502_yes_reg_table,
 435 };
 436
 437 /*
 438  * set_up_regulators() - initialize all regulators
 439  */
 440 static int setup_regulators(struct mcp16502 *mcp, struct device *dev,
 441                             struct regulator_config config)
 442 {
 443         int i;
 444
 445         for (i = 0; i < NUM_REGULATORS; i++) {
 446                 mcp->rdev[i] = devm_regulator_register(dev,
 447                                                        &mcp16502_desc[i],
 448                                                        &config);
 449                 if (IS_ERR(mcp->rdev[i])) {
 450                         dev_err(dev,
 451                                 "failed to register %s regulator %ld\n",
 452                                 mcp16502_desc[i].name, PTR_ERR(mcp->rdev[i]));
 453                         return PTR_ERR(mcp->rdev[i]);
 454                 }
 455         }
 456
 457         return 0;
 458 }
 459
 460 static int mcp16502_probe(struct i2c_client *client,
 461                           const struct i2c_device_id *id)
 462 {
 463         struct regulator_config config = { };
 464         struct device *dev;
 465         struct mcp16502 *mcp;
 466         int ret = 0;
 467
 468         dev = &client->dev;
 469         config.dev = dev;
 470
 471         mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
 472         if (!mcp)
 473                 return -ENOMEM;
 474
 475         mcp->rmap = devm_regmap_init_i2c(client, &mcp16502_regmap_config);
 476         if (IS_ERR(mcp->rmap)) {
 477                 ret = PTR_ERR(mcp->rmap);
 478                 dev_err(dev, "regmap init failed: %d\n", ret);
 479                 return ret;
 480         }
 481
 482         i2c_set_clientdata(client, mcp);
 483         config.regmap = mcp->rmap;
 484         config.driver_data = mcp;
 485
 486         mcp->lpm = devm_gpiod_get(dev, "lpm", GPIOD_OUT_LOW);
 487         if (IS_ERR(mcp->lpm)) {
 488                 dev_err(dev, "failed to get lpm pin: %ld\n", PTR_ERR(mcp->lpm));
 489                 return PTR_ERR(mcp->lpm);
 490         }
 491
 492         ret = setup_regulators(mcp, dev, config);
 493         if (ret != 0)
 494                 return ret;
 495
 496         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 497
 498         return 0;
 499 }
 500
 501 #ifdef CONFIG_PM_SLEEP
 502 static int mcp16502_suspend_noirq(struct device *dev)
 503 {
 504         struct i2c_client *client = to_i2c_client(dev);
 505         struct mcp16502 *mcp = i2c_get_clientdata(client);
 506
 507         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_LPM);
 508
 509         return 0;
 510 }
 511
 512 static int mcp16502_resume_noirq(struct device *dev)
 513 {
 514         struct i2c_client *client = to_i2c_client(dev);
 515         struct mcp16502 *mcp = i2c_get_clientdata(client);
 516
 517         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 518
 519         return 0;
 520 }
 521 #endif
 522
 523 #ifdef CONFIG_PM
 524 static const struct dev_pm_ops mcp16502_pm_ops = {
 525         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mcp16502_suspend_noirq,
 526                                       mcp16502_resume_noirq)
 527 };
 528 #endif
 529 static const struct i2c_device_id mcp16502_i2c_id[] = {
 530         { "mcp16502", 0 },
 531         { }
 532 };
 533 MODULE_DEVICE_TABLE(i2c, mcp16502_i2c_id);
 534
 535 static struct i2c_driver mcp16502_drv = {
 536         .probe          = mcp16502_probe,
 537         .driver         = {
 538                 .name   = "mcp16502-regulator",
 539                 .of_match_table = of_match_ptr(mcp16502_ids),
 540 #ifdef CONFIG_PM
 541                 .pm = &mcp16502_pm_ops,
 542 #endif
 543         },
 544         .id_table       = mcp16502_i2c_id,
 545 };
 546
 547 module_i2c_driver(mcp16502_drv);
 548
 549 MODULE_VERSION("1.0");
 550 MODULE_LICENSE("GPL v2");
 551 MODULE_DESCRIPTION("MCP16502 PMIC driver");
 552 MODULE_AUTHOR("Andrei Stefanescu andrei.stefanescu@microchip.com");