drivers/regulator/ab3100.c

   1 /*
   2  * drivers/regulator/ab3100.c
   3  *
   4  * Copyright (C) 2008-2009 ST-Ericsson AB
   5  * License terms: GNU General Public License (GPL) version 2
   6  * Low-level control of the AB3100 IC Low Dropout (LDO)
   7  * regulators, external regulator and buck converter
   8  * Author: Mattias Wallin <mattias.wallin@stericsson.com>
   9  * Author: Linus Walleij <linus.walleij@stericsson.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/err.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/regulator/driver.h>
  18 #include <linux/mfd/ab3100.h>
  19 #include <linux/mfd/abx500.h>
  20
  21 /* LDO registers and some handy masking definitions for AB3100 */
  22 #define AB3100_LDO_A            0x40
  23 #define AB3100_LDO_C            0x41
  24 #define AB3100_LDO_D            0x42
  25 #define AB3100_LDO_E            0x43
  26 #define AB3100_LDO_E_SLEEP      0x44
  27 #define AB3100_LDO_F            0x45
  28 #define AB3100_LDO_G            0x46
  29 #define AB3100_LDO_H            0x47
  30 #define AB3100_LDO_H_SLEEP_MODE 0
  31 #define AB3100_LDO_H_SLEEP_EN   2
  32 #define AB3100_LDO_ON           4
  33 #define AB3100_LDO_H_VSEL_AC    5
  34 #define AB3100_LDO_K            0x48
  35 #define AB3100_LDO_EXT          0x49
  36 #define AB3100_BUCK             0x4A
  37 #define AB3100_BUCK_SLEEP       0x4B
  38 #define AB3100_REG_ON_MASK      0x10
  39
  40 /**
  41  * struct ab3100_regulator
  42  * A struct passed around the individual regulator functions
  43  * @platform_device: platform device holding this regulator
  44  * @dev: handle to the device
  45  * @plfdata: AB3100 platform data passed in at probe time
  46  * @regreg: regulator register number in the AB3100
  47  */
  48 struct ab3100_regulator {
  49         struct regulator_dev *rdev;
  50         struct device *dev;
  51         struct ab3100_platform_data *plfdata;
  52         u8 regreg;
  53 };
  54
  55 /* The order in which registers are initialized */
  56 static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
  57         AB3100_LDO_A,
  58         AB3100_LDO_C,
  59         AB3100_LDO_E,
  60         AB3100_LDO_E_SLEEP,
  61         AB3100_LDO_F,
  62         AB3100_LDO_G,
  63         AB3100_LDO_H,
  64         AB3100_LDO_K,
  65         AB3100_LDO_EXT,
  66         AB3100_BUCK,
  67         AB3100_BUCK_SLEEP,
  68         AB3100_LDO_D,
  69 };
  70
  71 /* Preset (hardware defined) voltages for these regulators */
  72 #define LDO_A_VOLTAGE 2750000
  73 #define LDO_C_VOLTAGE 2650000
  74 #define LDO_D_VOLTAGE 2650000
  75
  76 static const unsigned int ldo_e_buck_typ_voltages[] = {
  77         1800000,
  78         1400000,
  79         1300000,
  80         1200000,
  81         1100000,
  82         1050000,
  83         900000,
  84 };
  85
  86 static const unsigned int ldo_f_typ_voltages[] = {
  87         1800000,
  88         1400000,
  89         1300000,
  90         1200000,
  91         1100000,
  92         1050000,
  93         2500000,
  94         2650000,
  95 };
  96
  97 static const unsigned int ldo_g_typ_voltages[] = {
  98         2850000,
  99         2750000,
 100         1800000,
 101         1500000,
 102 };
 103
 104 static const unsigned int ldo_h_typ_voltages[] = {
 105         2750000,
 106         1800000,
 107         1500000,
 108         1200000,
 109 };
 110
 111 static const unsigned int ldo_k_typ_voltages[] = {
 112         2750000,
 113         1800000,
 114 };
 115
 116
 117 /* The regulator devices */
 118 static struct ab3100_regulator
 119 ab3100_regulators[AB3100_NUM_REGULATORS] = {
 120         {
 121                 .regreg = AB3100_LDO_A,
 122         },
 123         {
 124                 .regreg = AB3100_LDO_C,
 125         },
 126         {
 127                 .regreg = AB3100_LDO_D,
 128         },
 129         {
 130                 .regreg = AB3100_LDO_E,
 131         },
 132         {
 133                 .regreg = AB3100_LDO_F,
 134         },
 135         {
 136                 .regreg = AB3100_LDO_G,
 137         },
 138         {
 139                 .regreg = AB3100_LDO_H,
 140         },
 141         {
 142                 .regreg = AB3100_LDO_K,
 143         },
 144         {
 145                 .regreg = AB3100_LDO_EXT,
 146                 /* No voltages for the external regulator */
 147         },
 148         {
 149                 .regreg = AB3100_BUCK,
 150         },
 151 };
 152
 153 /*
 154  * General functions for enable, disable and is_enabled used for
 155  * LDO: A,C,E,F,G,H,K,EXT and BUCK
 156  */
 157 static int ab3100_enable_regulator(struct regulator_dev *reg)
 158 {
 159         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 160         int err;
 161         u8 regval;
 162
 163         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 164                                                 &regval);
 165         if (err) {
 166                 dev_warn(&reg->dev, "failed to get regid %d value\n",
 167                          abreg->regreg);
 168                 return err;
 169         }
 170
 171         /* The regulator is already on, no reason to go further */
 172         if (regval & AB3100_REG_ON_MASK)
 173                 return 0;
 174
 175         regval |= AB3100_REG_ON_MASK;
 176
 177         err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
 178                                                 regval);
 179         if (err) {
 180                 dev_warn(&reg->dev, "failed to set regid %d value\n",
 181                          abreg->regreg);
 182                 return err;
 183         }
 184
 185         return 0;
 186 }
 187
 188 static int ab3100_disable_regulator(struct regulator_dev *reg)
 189 {
 190         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 191         int err;
 192         u8 regval;
 193
 194         /*
 195          * LDO D is a special regulator. When it is disabled, the entire
 196          * system is shut down. So this is handled specially.
 197          */
 198         pr_info("Called ab3100_disable_regulator\n");
 199         if (abreg->regreg == AB3100_LDO_D) {
 200                 dev_info(&reg->dev, "disabling LDO D - shut down system\n");
 201                 /* Setting LDO D to 0x00 cuts the power to the SoC */
 202                 return abx500_set_register_interruptible(abreg->dev, 0,
 203                                                          AB3100_LDO_D, 0x00U);
 204         }
 205
 206         /*
 207          * All other regulators are handled here
 208          */
 209         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 210                                                 &regval);
 211         if (err) {
 212                 dev_err(&reg->dev, "unable to get register 0x%x\n",
 213                         abreg->regreg);
 214                 return err;
 215         }
 216         regval &= ~AB3100_REG_ON_MASK;
 217         return abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
 218                                                  regval);
 219 }
 220
 221 static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
 222 {
 223         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 224         u8 regval;
 225         int err;
 226
 227         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 228                                                 &regval);
 229         if (err) {
 230                 dev_err(&reg->dev, "unable to get register 0x%x\n",
 231                         abreg->regreg);
 232                 return err;
 233         }
 234
 235         return regval & AB3100_REG_ON_MASK;
 236 }
 237
 238 static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
 239 {
 240         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 241         u8 regval;
 242         int err;
 243
 244         /*
 245          * For variable types, read out setting and index into
 246          * supplied voltage list.
 247          */
 248         err = abx500_get_register_interruptible(abreg->dev, 0,
 249                                                 abreg->regreg, &regval);
 250         if (err) {
 251                 dev_warn(&reg->dev,
 252                          "failed to get regulator value in register %02x\n",
 253                          abreg->regreg);
 254                 return err;
 255         }
 256
 257         /* The 3 highest bits index voltages */
 258         regval &= 0xE0;
 259         regval >>= 5;
 260
 261         if (regval >= reg->desc->n_voltages) {
 262                 dev_err(&reg->dev,
 263                         "regulator register %02x contains an illegal voltage setting\n",
 264                         abreg->regreg);
 265                 return -EINVAL;
 266         }
 267
 268         return reg->desc->volt_table[regval];
 269 }
 270
 271 static int ab3100_set_voltage_regulator_sel(struct regulator_dev *reg,
 272                                             unsigned selector)
 273 {
 274         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 275         u8 regval;
 276         int err;
 277
 278         err = abx500_get_register_interruptible(abreg->dev, 0,
 279                                                 abreg->regreg, &regval);
 280         if (err) {
 281                 dev_warn(&reg->dev,
 282                          "failed to get regulator register %02x\n",
 283                          abreg->regreg);
 284                 return err;
 285         }
 286
 287         /* The highest three bits control the variable regulators */
 288         regval &= ~0xE0;
 289         regval |= (selector << 5);
 290
 291         err = abx500_set_register_interruptible(abreg->dev, 0,
 292                                                 abreg->regreg, regval);
 293         if (err)
 294                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
 295                         abreg->regreg);
 296
 297         return err;
 298 }
 299
 300 static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
 301                                                 int uV)
 302 {
 303         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 304         u8 regval;
 305         int err;
 306         int bestindex;
 307         u8 targetreg;
 308
 309         if (abreg->regreg == AB3100_LDO_E)
 310                 targetreg = AB3100_LDO_E_SLEEP;
 311         else if (abreg->regreg == AB3100_BUCK)
 312                 targetreg = AB3100_BUCK_SLEEP;
 313         else
 314                 return -EINVAL;
 315
 316         /* LDO E and BUCK have special suspend voltages you can set */
 317         bestindex = regulator_map_voltage_iterate(reg, uV, uV);
 318
 319         err = abx500_get_register_interruptible(abreg->dev, 0,
 320                                                 targetreg, &regval);
 321         if (err) {
 322                 dev_warn(&reg->dev,
 323                          "failed to get regulator register %02x\n",
 324                          targetreg);
 325                 return err;
 326         }
 327
 328         /* The highest three bits control the variable regulators */
 329         regval &= ~0xE0;
 330         regval |= (bestindex << 5);
 331
 332         err = abx500_set_register_interruptible(abreg->dev, 0,
 333                                                 targetreg, regval);
 334         if (err)
 335                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
 336                         abreg->regreg);
 337
 338         return err;
 339 }
 340
 341 /*
 342  * The external regulator can just define a fixed voltage.
 343  */
 344 static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
 345 {
 346         struct ab3100_regulator *abreg = rdev_get_drvdata(reg);
 347
 348         return abreg->plfdata->external_voltage;
 349 }
 350
 351 static struct regulator_ops regulator_ops_fixed = {
 352         .list_voltage = regulator_list_voltage_linear,
 353         .enable      = ab3100_enable_regulator,
 354         .disable     = ab3100_disable_regulator,
 355         .is_enabled  = ab3100_is_enabled_regulator,
 356 };
 357
 358 static struct regulator_ops regulator_ops_variable = {
 359         .enable      = ab3100_enable_regulator,
 360         .disable     = ab3100_disable_regulator,
 361         .is_enabled  = ab3100_is_enabled_regulator,
 362         .get_voltage = ab3100_get_voltage_regulator,
 363         .set_voltage_sel = ab3100_set_voltage_regulator_sel,
 364         .list_voltage = regulator_list_voltage_table,
 365 };
 366
 367 static struct regulator_ops regulator_ops_variable_sleepable = {
 368         .enable      = ab3100_enable_regulator,
 369         .disable     = ab3100_disable_regulator,
 370         .is_enabled  = ab3100_is_enabled_regulator,
 371         .get_voltage = ab3100_get_voltage_regulator,
 372         .set_voltage_sel = ab3100_set_voltage_regulator_sel,
 373         .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
 374         .list_voltage = regulator_list_voltage_table,
 375 };
 376
 377 /*
 378  * LDO EXT is an external regulator so it is really
 379  * not possible to set any voltage locally here, AB3100
 380  * is an on/off switch plain an simple. The external
 381  * voltage is defined in the board set-up if any.
 382  */
 383 static struct regulator_ops regulator_ops_external = {
 384         .enable      = ab3100_enable_regulator,
 385         .disable     = ab3100_disable_regulator,
 386         .is_enabled  = ab3100_is_enabled_regulator,
 387         .get_voltage = ab3100_get_voltage_regulator_external,
 388 };
 389
 390 static struct regulator_desc
 391 ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
 392         {
 393                 .name = "LDO_A",
 394                 .id   = AB3100_LDO_A,
 395                 .ops  = &regulator_ops_fixed,
 396                 .n_voltages = 1,
 397                 .type = REGULATOR_VOLTAGE,
 398                 .owner = THIS_MODULE,
 399                 .min_uV = LDO_A_VOLTAGE,
 400                 .enable_time = 200,
 401         },
 402         {
 403                 .name = "LDO_C",
 404                 .id   = AB3100_LDO_C,
 405                 .ops  = &regulator_ops_fixed,
 406                 .n_voltages = 1,
 407                 .type = REGULATOR_VOLTAGE,
 408                 .owner = THIS_MODULE,
 409                 .min_uV = LDO_C_VOLTAGE,
 410                 .enable_time = 200,
 411         },
 412         {
 413                 .name = "LDO_D",
 414                 .id   = AB3100_LDO_D,
 415                 .ops  = &regulator_ops_fixed,
 416                 .n_voltages = 1,
 417                 .type = REGULATOR_VOLTAGE,
 418                 .owner = THIS_MODULE,
 419                 .min_uV = LDO_D_VOLTAGE,
 420                 .enable_time = 200,
 421         },
 422         {
 423                 .name = "LDO_E",
 424                 .id   = AB3100_LDO_E,
 425                 .ops  = &regulator_ops_variable_sleepable,
 426                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 427                 .volt_table = ldo_e_buck_typ_voltages,
 428                 .type = REGULATOR_VOLTAGE,
 429                 .owner = THIS_MODULE,
 430                 .enable_time = 200,
 431         },
 432         {
 433                 .name = "LDO_F",
 434                 .id   = AB3100_LDO_F,
 435                 .ops  = &regulator_ops_variable,
 436                 .n_voltages = ARRAY_SIZE(ldo_f_typ_voltages),
 437                 .volt_table = ldo_f_typ_voltages,
 438                 .type = REGULATOR_VOLTAGE,
 439                 .owner = THIS_MODULE,
 440                 .enable_time = 600,
 441         },
 442         {
 443                 .name = "LDO_G",
 444                 .id   = AB3100_LDO_G,
 445                 .ops  = &regulator_ops_variable,
 446                 .n_voltages = ARRAY_SIZE(ldo_g_typ_voltages),
 447                 .volt_table = ldo_g_typ_voltages,
 448                 .type = REGULATOR_VOLTAGE,
 449                 .owner = THIS_MODULE,
 450                 .enable_time = 400,
 451         },
 452         {
 453                 .name = "LDO_H",
 454                 .id   = AB3100_LDO_H,
 455                 .ops  = &regulator_ops_variable,
 456                 .n_voltages = ARRAY_SIZE(ldo_h_typ_voltages),
 457                 .volt_table = ldo_h_typ_voltages,
 458                 .type = REGULATOR_VOLTAGE,
 459                 .owner = THIS_MODULE,
 460                 .enable_time = 200,
 461         },
 462         {
 463                 .name = "LDO_K",
 464                 .id   = AB3100_LDO_K,
 465                 .ops  = &regulator_ops_variable,
 466                 .n_voltages = ARRAY_SIZE(ldo_k_typ_voltages),
 467                 .volt_table = ldo_k_typ_voltages,
 468                 .type = REGULATOR_VOLTAGE,
 469                 .owner = THIS_MODULE,
 470                 .enable_time = 200,
 471         },
 472         {
 473                 .name = "LDO_EXT",
 474                 .id   = AB3100_LDO_EXT,
 475                 .ops  = &regulator_ops_external,
 476                 .type = REGULATOR_VOLTAGE,
 477                 .owner = THIS_MODULE,
 478         },
 479         {
 480                 .name = "BUCK",
 481                 .id   = AB3100_BUCK,
 482                 .ops  = &regulator_ops_variable_sleepable,
 483                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 484                 .volt_table = ldo_e_buck_typ_voltages,
 485                 .type = REGULATOR_VOLTAGE,
 486                 .owner = THIS_MODULE,
 487                 .enable_time = 1000,
 488         },
 489 };
 490
 491 /*
 492  * NOTE: the following functions are regulators pluralis - it is the
 493  * binding to the AB3100 core driver and the parent platform device
 494  * for all the different regulators.
 495  */
 496
 497 static int ab3100_regulators_probe(struct platform_device *pdev)
 498 {
 499         struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
 500         struct regulator_config config = { };
 501         int err = 0;
 502         u8 data;
 503         int i;
 504
 505         /* Check chip state */
 506         err = abx500_get_register_interruptible(&pdev->dev, 0,
 507                                                 AB3100_LDO_D, &data);
 508         if (err) {
 509                 dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
 510                 return err;
 511         }
 512         if (data & 0x10)
 513                 dev_notice(&pdev->dev,
 514                            "chip is already in active mode (Warm start)\n");
 515         else
 516                 dev_notice(&pdev->dev,
 517                            "chip is in inactive mode (Cold start)\n");
 518
 519         /* Set up regulators */
 520         for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
 521                 err = abx500_set_register_interruptible(&pdev->dev, 0,
 522                                         ab3100_reg_init_order[i],
 523                                         plfdata->reg_initvals[i]);
 524                 if (err) {
 525                         dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
 526                                 err);
 527                         return err;
 528                 }
 529         }
 530
 531         /* Register the regulators */
 532         for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
 533                 struct ab3100_regulator *reg = &ab3100_regulators[i];
 534                 struct regulator_dev *rdev;
 535
 536                 /*
 537                  * Initialize per-regulator struct.
 538                  * Inherit platform data, this comes down from the
 539                  * i2c boarddata, from the machine. So if you want to
 540                  * see what it looks like for a certain machine, go
 541                  * into the machine I2C setup.
 542                  */
 543                 reg->dev = &pdev->dev;
 544                 reg->plfdata = plfdata;
 545
 546                 config.dev = &pdev->dev;
 547                 config.driver_data = reg;
 548                 config.init_data = &plfdata->reg_constraints[i];
 549
 550                 /*
 551                  * Register the regulator, pass around
 552                  * the ab3100_regulator struct
 553                  */
 554                 rdev = regulator_register(&ab3100_regulator_desc[i], &config);
 555                 if (IS_ERR(rdev)) {
 556                         err = PTR_ERR(rdev);
 557                         dev_err(&pdev->dev,
 558                                 "%s: failed to register regulator %s err %d\n",
 559                                 __func__, ab3100_regulator_desc[i].name,
 560                                 err);
 561                         /* remove the already registered regulators */
 562                         while (--i >= 0)
 563                                 regulator_unregister(ab3100_regulators[i].rdev);
 564                         return err;
 565                 }
 566
 567                 /* Then set a pointer back to the registered regulator */
 568                 reg->rdev = rdev;
 569         }
 570
 571         return 0;
 572 }
 573
 574 static int ab3100_regulators_remove(struct platform_device *pdev)
 575 {
 576         int i;
 577
 578         for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
 579                 struct ab3100_regulator *reg = &ab3100_regulators[i];
 580
 581                 regulator_unregister(reg->rdev);
 582         }
 583         return 0;
 584 }
 585
 586 static struct platform_driver ab3100_regulators_driver = {
 587         .driver = {
 588                 .name  = "ab3100-regulators",
 589                 .owner = THIS_MODULE,
 590         },
 591         .probe = ab3100_regulators_probe,
 592         .remove = ab3100_regulators_remove,
 593 };
 594
 595 static __init int ab3100_regulators_init(void)
 596 {
 597         return platform_driver_register(&ab3100_regulators_driver);
 598 }
 599
 600 static __exit void ab3100_regulators_exit(void)
 601 {
 602         platform_driver_unregister(&ab3100_regulators_driver);
 603 }
 604
 605 subsys_initcall(ab3100_regulators_init);
 606 module_exit(ab3100_regulators_exit);
 607
 608 MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
 609 MODULE_DESCRIPTION("AB3100 Regulator driver");
 610 MODULE_LICENSE("GPL");
 611 MODULE_ALIAS("platform:ab3100-regulators");