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 gpio_desc *lpm;
 123 };
 124
 125 /*
 126  * mcp16502_gpio_set_mode() - set the GPIO corresponding value
 127  *
 128  * Used to prepare transitioning into hibernate or resuming from it.
 129  */
 130 static void mcp16502_gpio_set_mode(struct mcp16502 *mcp, int mode)
 131 {
 132         switch (mode) {
 133         case MCP16502_OPMODE_ACTIVE:
 134                 gpiod_set_value(mcp->lpm, 0);
 135                 break;
 136         case MCP16502_OPMODE_LPM:
 137         case MCP16502_OPMODE_HIB:
 138                 gpiod_set_value(mcp->lpm, 1);
 139                 break;
 140         default:
 141                 pr_err("%s: %d invalid\n", __func__, mode);
 142         }
 143 }
 144
 145 /*
 146  * mcp16502_get_reg() - get the PMIC's configuration register for opmode
 147  *
 148  * @rdev: the regulator whose register we are searching
 149  * @opmode: the PMIC's operating mode ACTIVE, Low-power, Hibernate
 150  */
 151 static int mcp16502_get_reg(struct regulator_dev *rdev, int opmode)
 152 {
 153         int reg = MCP16502_BASE(rdev_get_id(rdev));
 154
 155         switch (opmode) {
 156         case MCP16502_OPMODE_ACTIVE:
 157                 return reg + MCP16502_OFFSET_MODE_A;
 158         case MCP16502_OPMODE_LPM:
 159                 return reg + MCP16502_OFFSET_MODE_LPM;
 160         case MCP16502_OPMODE_HIB:
 161                 return reg + MCP16502_OFFSET_MODE_HIB;
 162         default:
 163                 return -EINVAL;
 164         }
 165 }
 166
 167 /*
 168  * mcp16502_get_mode() - return the current operating mode of a regulator
 169  *
 170  * Note: all functions that are not part of entering/exiting standby/suspend
 171  *       use the Active mode registers.
 172  *
 173  * Note: this is different from the PMIC's operatig mode, it is the
 174  *       MODE bit from the regulator's register.
 175  */
 176 static unsigned int mcp16502_get_mode(struct regulator_dev *rdev)
 177 {
 178         unsigned int val;
 179         int ret, reg;
 180
 181         reg = mcp16502_get_reg(rdev, MCP16502_OPMODE_ACTIVE);
 182         if (reg < 0)
 183                 return reg;
 184
 185         ret = regmap_read(rdev->regmap, reg, &val);
 186         if (ret)
 187                 return ret;
 188
 189         switch (val & MCP16502_MODE) {
 190         case MCP16502_MODE_FPWM:
 191                 return REGULATOR_MODE_NORMAL;
 192         case MCP16502_MODE_AUTO_PFM:
 193                 return REGULATOR_MODE_IDLE;
 194         default:
 195                 return REGULATOR_MODE_INVALID;
 196         }
 197 }
 198
 199 /*
 200  * _mcp16502_set_mode() - helper for set_mode and set_suspend_mode
 201  *
 202  * @rdev: the regulator for which we are setting the mode
 203  * @mode: the regulator's mode (the one from MODE bit)
 204  * @opmode: the PMIC's operating mode: Active/Low-power/Hibernate
 205  */
 206 static int _mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode,
 207                               unsigned int op_mode)
 208 {
 209         int val;
 210         int reg;
 211
 212         reg = mcp16502_get_reg(rdev, op_mode);
 213         if (reg < 0)
 214                 return reg;
 215
 216         switch (mode) {
 217         case REGULATOR_MODE_NORMAL:
 218                 val = MCP16502_MODE_FPWM;
 219                 break;
 220         case REGULATOR_MODE_IDLE:
 221                 val = MCP16502_MODE_AUTO_PFM;
 222                 break;
 223         default:
 224                 return -EINVAL;
 225         }
 226
 227         reg = regmap_update_bits(rdev->regmap, reg, MCP16502_MODE, val);
 228         return reg;
 229 }
 230
 231 /*
 232  * mcp16502_set_mode() - regulator_ops set_mode
 233  */
 234 static int mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode)
 235 {
 236         return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_ACTIVE);
 237 }
 238
 239 /*
 240  * mcp16502_get_status() - regulator_ops get_status
 241  */
 242 static int mcp16502_get_status(struct regulator_dev *rdev)
 243 {
 244         int ret;
 245         unsigned int val;
 246
 247         ret = regmap_read(rdev->regmap, MCP16502_STAT_BASE(rdev_get_id(rdev)),
 248                           &val);
 249         if (ret)
 250                 return ret;
 251
 252         if (val & MCP16502_FLT)
 253                 return REGULATOR_STATUS_ERROR;
 254         else if (val & MCP16502_ENS)
 255                 return REGULATOR_STATUS_ON;
 256         else if (!(val & MCP16502_ENS))
 257                 return REGULATOR_STATUS_OFF;
 258
 259         return REGULATOR_STATUS_UNDEFINED;
 260 }
 261
 262 #ifdef CONFIG_SUSPEND
 263 /*
 264  * mcp16502_suspend_get_target_reg() - get the reg of the target suspend PMIC
 265  *                                     mode
 266  */
 267 static int mcp16502_suspend_get_target_reg(struct regulator_dev *rdev)
 268 {
 269         switch (pm_suspend_target_state) {
 270         case PM_SUSPEND_STANDBY:
 271                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_LPM);
 272         case PM_SUSPEND_ON:
 273         case PM_SUSPEND_MEM:
 274                 return mcp16502_get_reg(rdev, MCP16502_OPMODE_HIB);
 275         default:
 276                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 277                         pm_suspend_target_state);
 278         }
 279
 280         return -EINVAL;
 281 }
 282
 283 /*
 284  * mcp16502_set_suspend_voltage() - regulator_ops set_suspend_voltage
 285  */
 286 static int mcp16502_set_suspend_voltage(struct regulator_dev *rdev, int uV)
 287 {
 288         int sel = regulator_map_voltage_linear_range(rdev, uV, uV);
 289         int reg = mcp16502_suspend_get_target_reg(rdev);
 290
 291         if (sel < 0)
 292                 return sel;
 293
 294         if (reg < 0)
 295                 return reg;
 296
 297         return regmap_update_bits(rdev->regmap, reg, MCP16502_VSEL, sel);
 298 }
 299
 300 /*
 301  * mcp16502_set_suspend_mode() - regulator_ops set_suspend_mode
 302  */
 303 static int mcp16502_set_suspend_mode(struct regulator_dev *rdev,
 304                                      unsigned int mode)
 305 {
 306         switch (pm_suspend_target_state) {
 307         case PM_SUSPEND_STANDBY:
 308                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_LPM);
 309         case PM_SUSPEND_ON:
 310         case PM_SUSPEND_MEM:
 311                 return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_HIB);
 312         default:
 313                 dev_err(&rdev->dev, "invalid suspend target: %d\n",
 314                         pm_suspend_target_state);
 315         }
 316
 317         return -EINVAL;
 318 }
 319
 320 /*
 321  * mcp16502_set_suspend_enable() - regulator_ops set_suspend_enable
 322  */
 323 static int mcp16502_set_suspend_enable(struct regulator_dev *rdev)
 324 {
 325         int reg = mcp16502_suspend_get_target_reg(rdev);
 326
 327         if (reg < 0)
 328                 return reg;
 329
 330         return regmap_update_bits(rdev->regmap, reg, MCP16502_EN, MCP16502_EN);
 331 }
 332
 333 /*
 334  * mcp16502_set_suspend_disable() - regulator_ops set_suspend_disable
 335  */
 336 static int mcp16502_set_suspend_disable(struct regulator_dev *rdev)
 337 {
 338         int reg = mcp16502_suspend_get_target_reg(rdev);
 339
 340         if (reg < 0)
 341                 return reg;
 342
 343         return regmap_update_bits(rdev->regmap, reg, MCP16502_EN, 0);
 344 }
 345 #endif /* CONFIG_SUSPEND */
 346
 347 static const struct regulator_ops mcp16502_buck_ops = {
 348         .list_voltage                   = regulator_list_voltage_linear_range,
 349         .map_voltage                    = regulator_map_voltage_linear_range,
 350         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 351         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 352         .enable                         = regulator_enable_regmap,
 353         .disable                        = regulator_disable_regmap,
 354         .is_enabled                     = regulator_is_enabled_regmap,
 355         .get_status                     = mcp16502_get_status,
 356
 357         .set_mode                       = mcp16502_set_mode,
 358         .get_mode                       = mcp16502_get_mode,
 359
 360 #ifdef CONFIG_SUSPEND
 361         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 362         .set_suspend_mode               = mcp16502_set_suspend_mode,
 363         .set_suspend_enable             = mcp16502_set_suspend_enable,
 364         .set_suspend_disable            = mcp16502_set_suspend_disable,
 365 #endif /* CONFIG_SUSPEND */
 366 };
 367
 368 /*
 369  * LDOs cannot change operating modes.
 370  */
 371 static const struct regulator_ops mcp16502_ldo_ops = {
 372         .list_voltage                   = regulator_list_voltage_linear_range,
 373         .map_voltage                    = regulator_map_voltage_linear_range,
 374         .get_voltage_sel                = regulator_get_voltage_sel_regmap,
 375         .set_voltage_sel                = regulator_set_voltage_sel_regmap,
 376         .enable                         = regulator_enable_regmap,
 377         .disable                        = regulator_disable_regmap,
 378         .is_enabled                     = regulator_is_enabled_regmap,
 379         .get_status                     = mcp16502_get_status,
 380
 381 #ifdef CONFIG_SUSPEND
 382         .set_suspend_voltage            = mcp16502_set_suspend_voltage,
 383         .set_suspend_enable             = mcp16502_set_suspend_enable,
 384         .set_suspend_disable            = mcp16502_set_suspend_disable,
 385 #endif /* CONFIG_SUSPEND */
 386 };
 387
 388 static const struct of_device_id mcp16502_ids[] = {
 389         { .compatible = "microchip,mcp16502", },
 390         {}
 391 };
 392 MODULE_DEVICE_TABLE(of, mcp16502_ids);
 393
 394 static const struct linear_range b1l12_ranges[] = {
 395         REGULATOR_LINEAR_RANGE(1200000, VDD_LOW_SEL, VDD_HIGH_SEL, 50000),
 396 };
 397
 398 static const struct linear_range b234_ranges[] = {
 399         REGULATOR_LINEAR_RANGE(600000, VDD_LOW_SEL, VDD_HIGH_SEL, 25000),
 400 };
 401
 402 static const struct regulator_desc mcp16502_desc[] = {
 403         /* MCP16502_REGULATOR(_name, _id, ranges, regulator_ops) */
 404         MCP16502_REGULATOR("VDD_IO", BUCK1, b1l12_ranges, mcp16502_buck_ops),
 405         MCP16502_REGULATOR("VDD_DDR", BUCK2, b234_ranges, mcp16502_buck_ops),
 406         MCP16502_REGULATOR("VDD_CORE", BUCK3, b234_ranges, mcp16502_buck_ops),
 407         MCP16502_REGULATOR("VDD_OTHER", BUCK4, b234_ranges, mcp16502_buck_ops),
 408         MCP16502_REGULATOR("LDO1", LDO1, b1l12_ranges, mcp16502_ldo_ops),
 409         MCP16502_REGULATOR("LDO2", LDO2, b1l12_ranges, mcp16502_ldo_ops)
 410 };
 411
 412 static const struct regmap_range mcp16502_ranges[] = {
 413         regmap_reg_range(MCP16502_MIN_REG, MCP16502_MAX_REG)
 414 };
 415
 416 static const struct regmap_access_table mcp16502_yes_reg_table = {
 417         .yes_ranges = mcp16502_ranges,
 418         .n_yes_ranges = ARRAY_SIZE(mcp16502_ranges),
 419 };
 420
 421 static const struct regmap_config mcp16502_regmap_config = {
 422         .reg_bits       = 8,
 423         .val_bits       = 8,
 424         .max_register   = MCP16502_MAX_REG,
 425         .cache_type     = REGCACHE_NONE,
 426         .rd_table       = &mcp16502_yes_reg_table,
 427         .wr_table       = &mcp16502_yes_reg_table,
 428 };
 429
 430 static int mcp16502_probe(struct i2c_client *client,
 431                           const struct i2c_device_id *id)
 432 {
 433         struct regulator_config config = { };
 434         struct regulator_dev *rdev;
 435         struct device *dev;
 436         struct mcp16502 *mcp;
 437         struct regmap *rmap;
 438         int i, ret;
 439
 440         dev = &client->dev;
 441         config.dev = dev;
 442
 443         mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
 444         if (!mcp)
 445                 return -ENOMEM;
 446
 447         rmap = devm_regmap_init_i2c(client, &mcp16502_regmap_config);
 448         if (IS_ERR(rmap)) {
 449                 ret = PTR_ERR(rmap);
 450                 dev_err(dev, "regmap init failed: %d\n", ret);
 451                 return ret;
 452         }
 453
 454         i2c_set_clientdata(client, mcp);
 455         config.regmap = rmap;
 456         config.driver_data = mcp;
 457
 458         mcp->lpm = devm_gpiod_get(dev, "lpm", GPIOD_OUT_LOW);
 459         if (IS_ERR(mcp->lpm)) {
 460                 dev_err(dev, "failed to get lpm pin: %ld\n", PTR_ERR(mcp->lpm));
 461                 return PTR_ERR(mcp->lpm);
 462         }
 463
 464         for (i = 0; i < NUM_REGULATORS; i++) {
 465                 rdev = devm_regulator_register(dev, &mcp16502_desc[i], &config);
 466                 if (IS_ERR(rdev)) {
 467                         dev_err(dev,
 468                                 "failed to register %s regulator %ld\n",
 469                                 mcp16502_desc[i].name, PTR_ERR(rdev));
 470                         return PTR_ERR(rdev);
 471                 }
 472         }
 473
 474         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 475
 476         return 0;
 477 }
 478
 479 #ifdef CONFIG_PM_SLEEP
 480 static int mcp16502_suspend_noirq(struct device *dev)
 481 {
 482         struct i2c_client *client = to_i2c_client(dev);
 483         struct mcp16502 *mcp = i2c_get_clientdata(client);
 484
 485         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_LPM);
 486
 487         return 0;
 488 }
 489
 490 static int mcp16502_resume_noirq(struct device *dev)
 491 {
 492         struct i2c_client *client = to_i2c_client(dev);
 493         struct mcp16502 *mcp = i2c_get_clientdata(client);
 494
 495         mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE);
 496
 497         return 0;
 498 }
 499 #endif
 500
 501 #ifdef CONFIG_PM
 502 static const struct dev_pm_ops mcp16502_pm_ops = {
 503         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mcp16502_suspend_noirq,
 504                                       mcp16502_resume_noirq)
 505 };
 506 #endif
 507 static const struct i2c_device_id mcp16502_i2c_id[] = {
 508         { "mcp16502", 0 },
 509         { }
 510 };
 511 MODULE_DEVICE_TABLE(i2c, mcp16502_i2c_id);
 512
 513 static struct i2c_driver mcp16502_drv = {
 514         .probe          = mcp16502_probe,
 515         .driver         = {
 516                 .name   = "mcp16502-regulator",
 517                 .of_match_table = of_match_ptr(mcp16502_ids),
 518 #ifdef CONFIG_PM
 519                 .pm = &mcp16502_pm_ops,
 520 #endif
 521         },
 522         .id_table       = mcp16502_i2c_id,
 523 };
 524
 525 module_i2c_driver(mcp16502_drv);
 526
 527 MODULE_LICENSE("GPL v2");
 528 MODULE_DESCRIPTION("MCP16502 PMIC driver");
 529 MODULE_AUTHOR("Andrei Stefanescu andrei.stefanescu@microchip.com");