drivers/regulator/ltc3589.c

   1 /*
   2  * Linear Technology LTC3589,LTC3589-1 regulator support
   3  *
   4  * Copyright (c) 2014 Philipp Zabel <p.zabel@pengutronix.de>, Pengutronix
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2
  11  * as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  */
  19 #include <linux/i2c.h>
  20 #include <linux/init.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/of.h>
  25 #include <linux/of_device.h>
  26 #include <linux/regmap.h>
  27 #include <linux/regulator/driver.h>
  28 #include <linux/regulator/of_regulator.h>
  29
  30 #define DRIVER_NAME             "ltc3589"
  31
  32 #define LTC3589_IRQSTAT         0x02
  33 #define LTC3589_SCR1            0x07
  34 #define LTC3589_OVEN            0x10
  35 #define LTC3589_SCR2            0x12
  36 #define LTC3589_PGSTAT          0x13
  37 #define LTC3589_VCCR            0x20
  38 #define LTC3589_CLIRQ           0x21
  39 #define LTC3589_B1DTV1          0x23
  40 #define LTC3589_B1DTV2          0x24
  41 #define LTC3589_VRRCR           0x25
  42 #define LTC3589_B2DTV1          0x26
  43 #define LTC3589_B2DTV2          0x27
  44 #define LTC3589_B3DTV1          0x29
  45 #define LTC3589_B3DTV2          0x2a
  46 #define LTC3589_L2DTV1          0x32
  47 #define LTC3589_L2DTV2          0x33
  48
  49 #define LTC3589_IRQSTAT_PGOOD_TIMEOUT   BIT(3)
  50 #define LTC3589_IRQSTAT_UNDERVOLT_WARN  BIT(4)
  51 #define LTC3589_IRQSTAT_UNDERVOLT_FAULT BIT(5)
  52 #define LTC3589_IRQSTAT_THERMAL_WARN    BIT(6)
  53 #define LTC3589_IRQSTAT_THERMAL_FAULT   BIT(7)
  54
  55 #define LTC3589_OVEN_SW1                BIT(0)
  56 #define LTC3589_OVEN_SW2                BIT(1)
  57 #define LTC3589_OVEN_SW3                BIT(2)
  58 #define LTC3589_OVEN_BB_OUT             BIT(3)
  59 #define LTC3589_OVEN_LDO2               BIT(4)
  60 #define LTC3589_OVEN_LDO3               BIT(5)
  61 #define LTC3589_OVEN_LDO4               BIT(6)
  62 #define LTC3589_OVEN_SW_CTRL            BIT(7)
  63
  64 #define LTC3589_VCCR_SW1_GO             BIT(0)
  65 #define LTC3589_VCCR_SW2_GO             BIT(2)
  66 #define LTC3589_VCCR_SW3_GO             BIT(4)
  67 #define LTC3589_VCCR_LDO2_GO            BIT(6)
  68
  69 enum ltc3589_variant {
  70         LTC3589,
  71         LTC3589_1,
  72         LTC3589_2,
  73 };
  74
  75 enum ltc3589_reg {
  76         LTC3589_SW1,
  77         LTC3589_SW2,
  78         LTC3589_SW3,
  79         LTC3589_BB_OUT,
  80         LTC3589_LDO1,
  81         LTC3589_LDO2,
  82         LTC3589_LDO3,
  83         LTC3589_LDO4,
  84         LTC3589_NUM_REGULATORS,
  85 };
  86
  87 struct ltc3589_regulator {
  88         struct regulator_desc desc;
  89
  90         /* External feedback voltage divider */
  91         unsigned int r1;
  92         unsigned int r2;
  93 };
  94
  95 struct ltc3589 {
  96         struct regmap *regmap;
  97         struct device *dev;
  98         enum ltc3589_variant variant;
  99         struct ltc3589_regulator regulator_descs[LTC3589_NUM_REGULATORS];
 100         struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];
 101 };
 102
 103 static const int ltc3589_ldo4[] = {
 104         2800000, 2500000, 1800000, 3300000,
 105 };
 106
 107 static const int ltc3589_12_ldo4[] = {
 108         1200000, 1800000, 2500000, 3200000,
 109 };
 110
 111 static int ltc3589_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
 112 {
 113         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
 114         int sel, shift;
 115
 116         if (unlikely(ramp_delay <= 0))
 117                 return -EINVAL;
 118
 119         /* VRRCR slew rate offsets are the same as VCCR go bit offsets */
 120         shift = ffs(rdev->desc->apply_bit) - 1;
 121
 122         /* The slew rate can be set to 0.88, 1.75, 3.5, or 7 mV/uS */
 123         for (sel = 0; sel < 4; sel++) {
 124                 if ((880 << sel) >= ramp_delay) {
 125                         return regmap_update_bits(ltc3589->regmap,
 126                                                   LTC3589_VRRCR,
 127                                                   0x3 << shift, sel << shift);
 128                 }
 129         }
 130         return -EINVAL;
 131 }
 132
 133 static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)
 134 {
 135         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
 136         int sel;
 137
 138         sel = regulator_map_voltage_linear(rdev, uV, uV);
 139         if (sel < 0)
 140                 return sel;
 141
 142         /* DTV2 register follows right after the corresponding DTV1 register */
 143         return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,
 144                                   rdev->desc->vsel_mask, sel);
 145 }
 146
 147 static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,
 148                                     unsigned int mode)
 149 {
 150         struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);
 151         int mask, bit = 0;
 152
 153         /* VCCR reference selects are right next to the VCCR go bits */
 154         mask = rdev->desc->apply_bit << 1;
 155
 156         if (mode == REGULATOR_MODE_STANDBY)
 157                 bit = mask;     /* Select DTV2 */
 158
 159         mask |= rdev->desc->apply_bit;
 160         bit |= rdev->desc->apply_bit;
 161         return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);
 162 }
 163
 164 /* SW1, SW2, SW3, LDO2 */
 165 static const struct regulator_ops ltc3589_linear_regulator_ops = {
 166         .enable = regulator_enable_regmap,
 167         .disable = regulator_disable_regmap,
 168         .is_enabled = regulator_is_enabled_regmap,
 169         .list_voltage = regulator_list_voltage_linear,
 170         .set_voltage_sel = regulator_set_voltage_sel_regmap,
 171         .get_voltage_sel = regulator_get_voltage_sel_regmap,
 172         .set_ramp_delay = ltc3589_set_ramp_delay,
 173         .set_voltage_time_sel = regulator_set_voltage_time_sel,
 174         .set_suspend_voltage = ltc3589_set_suspend_voltage,
 175         .set_suspend_mode = ltc3589_set_suspend_mode,
 176 };
 177
 178 /* BB_OUT, LDO3 */
 179 static const struct regulator_ops ltc3589_fixed_regulator_ops = {
 180         .enable = regulator_enable_regmap,
 181         .disable = regulator_disable_regmap,
 182         .is_enabled = regulator_is_enabled_regmap,
 183 };
 184
 185 /* LDO1 */
 186 static const struct regulator_ops ltc3589_fixed_standby_regulator_ops = {
 187 };
 188
 189 /* LDO4 */
 190 static const struct regulator_ops ltc3589_table_regulator_ops = {
 191         .enable = regulator_enable_regmap,
 192         .disable = regulator_disable_regmap,
 193         .is_enabled = regulator_is_enabled_regmap,
 194         .list_voltage = regulator_list_voltage_table,
 195         .set_voltage_sel = regulator_set_voltage_sel_regmap,
 196         .get_voltage_sel = regulator_get_voltage_sel_regmap,
 197 };
 198
 199
 200 #define LTC3589_REG(_name, _ops, en_bit, dtv1_reg, dtv_mask, go_bit)    \
 201         [LTC3589_ ## _name] = {                                         \
 202                 .desc = {                                               \
 203                         .name = #_name,                                 \
 204                         .n_voltages = (dtv_mask) + 1,                   \
 205                         .min_uV = (go_bit) ? 362500 : 0,                \
 206                         .uV_step = (go_bit) ? 12500 : 0,                \
 207                         .ramp_delay = (go_bit) ? 1750 : 0,              \
 208                         .fixed_uV = (dtv_mask) ? 0 : 800000,            \
 209                         .ops = &ltc3589_ ## _ops ## _regulator_ops,     \
 210                         .type = REGULATOR_VOLTAGE,                      \
 211                         .id = LTC3589_ ## _name,                        \
 212                         .owner = THIS_MODULE,                           \
 213                         .vsel_reg = (dtv1_reg),                 \
 214                         .vsel_mask = (dtv_mask),                        \
 215                         .apply_reg = (go_bit) ? LTC3589_VCCR : 0,       \
 216                         .apply_bit = (go_bit),                          \
 217                         .enable_reg = (en_bit) ? LTC3589_OVEN : 0,      \
 218                         .enable_mask = (en_bit),                        \
 219                 },                                                      \
 220         }
 221
 222 #define LTC3589_LINEAR_REG(_name, _dtv1)                                \
 223         LTC3589_REG(_name, linear, LTC3589_OVEN_ ## _name,              \
 224                     LTC3589_ ## _dtv1, 0x1f,                            \
 225                     LTC3589_VCCR_ ## _name ## _GO)
 226
 227 #define LTC3589_FIXED_REG(_name) \
 228         LTC3589_REG(_name, fixed, LTC3589_OVEN_ ## _name, 0, 0, 0)
 229
 230 static struct ltc3589_regulator ltc3589_regulators[LTC3589_NUM_REGULATORS] = {
 231         LTC3589_LINEAR_REG(SW1, B1DTV1),
 232         LTC3589_LINEAR_REG(SW2, B2DTV1),
 233         LTC3589_LINEAR_REG(SW3, B3DTV1),
 234         LTC3589_FIXED_REG(BB_OUT),
 235         LTC3589_REG(LDO1, fixed_standby, 0, 0, 0, 0),
 236         LTC3589_LINEAR_REG(LDO2, L2DTV1),
 237         LTC3589_FIXED_REG(LDO3),
 238         LTC3589_REG(LDO4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60, 0),
 239 };
 240
 241 #ifdef CONFIG_OF
 242 static struct of_regulator_match ltc3589_matches[LTC3589_NUM_REGULATORS] = {
 243         { .name = "sw1",    },
 244         { .name = "sw2",    },
 245         { .name = "sw3",    },
 246         { .name = "bb-out", },
 247         { .name = "ldo1",   }, /* standby */
 248         { .name = "ldo2",   },
 249         { .name = "ldo3",   },
 250         { .name = "ldo4",   },
 251 };
 252
 253 static int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)
 254 {
 255         struct device *dev = ltc3589->dev;
 256         struct device_node *node;
 257         int i, ret;
 258
 259         node = of_get_child_by_name(dev->of_node, "regulators");
 260         if (!node) {
 261                 dev_err(dev, "regulators node not found\n");
 262                 return -EINVAL;
 263         }
 264
 265         ret = of_regulator_match(dev, node, ltc3589_matches,
 266                                  ARRAY_SIZE(ltc3589_matches));
 267         of_node_put(node);
 268         if (ret < 0) {
 269                 dev_err(dev, "Error parsing regulator init data: %d\n", ret);
 270                 return ret;
 271         }
 272         if (ret != LTC3589_NUM_REGULATORS) {
 273                 dev_err(dev, "Only %d regulators described in device tree\n",
 274                         ret);
 275                 return -EINVAL;
 276         }
 277
 278         /* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */
 279         for (i = 0; i < LTC3589_LDO3; i++) {
 280                 struct ltc3589_regulator *desc = &ltc3589->regulator_descs[i];
 281                 struct device_node *np = ltc3589_matches[i].of_node;
 282                 u32 vdiv[2];
 283
 284                 ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider",
 285                                                  vdiv, 2);
 286                 if (ret) {
 287                         dev_err(dev, "Failed to parse voltage divider: %d\n",
 288                                 ret);
 289                         return ret;
 290                 }
 291
 292                 desc->r1 = vdiv[0];
 293                 desc->r2 = vdiv[1];
 294         }
 295
 296         return 0;
 297 }
 298
 299 static inline struct regulator_init_data *match_init_data(int index)
 300 {
 301         return ltc3589_matches[index].init_data;
 302 }
 303
 304 static inline struct device_node *match_of_node(int index)
 305 {
 306         return ltc3589_matches[index].of_node;
 307 }
 308 #else
 309 static inline int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)
 310 {
 311         return 0;
 312 }
 313
 314 static inline struct regulator_init_data *match_init_data(int index)
 315 {
 316         return NULL;
 317 }
 318
 319 static inline struct device_node *match_of_node(int index)
 320 {
 321         return NULL;
 322 }
 323 #endif
 324
 325 static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)
 326 {
 327         switch (reg) {
 328         case LTC3589_IRQSTAT:
 329         case LTC3589_SCR1:
 330         case LTC3589_OVEN:
 331         case LTC3589_SCR2:
 332         case LTC3589_VCCR:
 333         case LTC3589_CLIRQ:
 334         case LTC3589_B1DTV1:
 335         case LTC3589_B1DTV2:
 336         case LTC3589_VRRCR:
 337         case LTC3589_B2DTV1:
 338         case LTC3589_B2DTV2:
 339         case LTC3589_B3DTV1:
 340         case LTC3589_B3DTV2:
 341         case LTC3589_L2DTV1:
 342         case LTC3589_L2DTV2:
 343                 return true;
 344         }
 345         return false;
 346 }
 347
 348 static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)
 349 {
 350         switch (reg) {
 351         case LTC3589_IRQSTAT:
 352         case LTC3589_SCR1:
 353         case LTC3589_OVEN:
 354         case LTC3589_SCR2:
 355         case LTC3589_PGSTAT:
 356         case LTC3589_VCCR:
 357         case LTC3589_B1DTV1:
 358         case LTC3589_B1DTV2:
 359         case LTC3589_VRRCR:
 360         case LTC3589_B2DTV1:
 361         case LTC3589_B2DTV2:
 362         case LTC3589_B3DTV1:
 363         case LTC3589_B3DTV2:
 364         case LTC3589_L2DTV1:
 365         case LTC3589_L2DTV2:
 366                 return true;
 367         }
 368         return false;
 369 }
 370
 371 static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)
 372 {
 373         switch (reg) {
 374         case LTC3589_IRQSTAT:
 375         case LTC3589_PGSTAT:
 376         case LTC3589_VCCR:
 377                 return true;
 378         }
 379         return false;
 380 }
 381
 382 static const struct reg_default ltc3589_reg_defaults[] = {
 383         { LTC3589_SCR1,   0x00 },
 384         { LTC3589_OVEN,   0x00 },
 385         { LTC3589_SCR2,   0x00 },
 386         { LTC3589_VCCR,   0x00 },
 387         { LTC3589_B1DTV1, 0x19 },
 388         { LTC3589_B1DTV2, 0x19 },
 389         { LTC3589_VRRCR,  0xff },
 390         { LTC3589_B2DTV1, 0x19 },
 391         { LTC3589_B2DTV2, 0x19 },
 392         { LTC3589_B3DTV1, 0x19 },
 393         { LTC3589_B3DTV2, 0x19 },
 394         { LTC3589_L2DTV1, 0x19 },
 395         { LTC3589_L2DTV2, 0x19 },
 396 };
 397
 398 static const struct regmap_config ltc3589_regmap_config = {
 399         .reg_bits = 8,
 400         .val_bits = 8,
 401         .writeable_reg = ltc3589_writeable_reg,
 402         .readable_reg = ltc3589_readable_reg,
 403         .volatile_reg = ltc3589_volatile_reg,
 404         .max_register = LTC3589_L2DTV2,
 405         .reg_defaults = ltc3589_reg_defaults,
 406         .num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),
 407         .use_single_rw = true,
 408         .cache_type = REGCACHE_RBTREE,
 409 };
 410
 411
 412 static irqreturn_t ltc3589_isr(int irq, void *dev_id)
 413 {
 414         struct ltc3589 *ltc3589 = dev_id;
 415         unsigned int i, irqstat, event;
 416
 417         regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);
 418
 419         if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {
 420                 event = REGULATOR_EVENT_OVER_TEMP;
 421                 for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
 422                         regulator_notifier_call_chain(ltc3589->regulators[i],
 423                                                       event, NULL);
 424         }
 425
 426         if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {
 427                 event = REGULATOR_EVENT_UNDER_VOLTAGE;
 428                 for (i = 0; i < LTC3589_NUM_REGULATORS; i++)
 429                         regulator_notifier_call_chain(ltc3589->regulators[i],
 430                                                       event, NULL);
 431         }
 432
 433         /* Clear warning condition */
 434         regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);
 435
 436         return IRQ_HANDLED;
 437 }
 438
 439 static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)
 440 {
 441         uint64_t tmp;
 442         if (uV == 0)
 443                 return 0;
 444         tmp = (uint64_t)uV * r1;
 445         do_div(tmp, r2);
 446         return uV + (unsigned int)tmp;
 447 }
 448
 449 static void ltc3589_apply_fb_voltage_divider(struct ltc3589_regulator *rdesc)
 450 {
 451         struct regulator_desc *desc = &rdesc->desc;
 452
 453         if (!rdesc->r1 || !rdesc->r2)
 454                 return;
 455
 456         desc->min_uV = ltc3589_scale(desc->min_uV, rdesc->r1, rdesc->r2);
 457         desc->uV_step = ltc3589_scale(desc->uV_step, rdesc->r1, rdesc->r2);
 458         desc->fixed_uV = ltc3589_scale(desc->fixed_uV, rdesc->r1, rdesc->r2);
 459 }
 460
 461 static int ltc3589_probe(struct i2c_client *client,
 462                          const struct i2c_device_id *id)
 463 {
 464         struct device *dev = &client->dev;
 465         struct ltc3589_regulator *descs;
 466         struct ltc3589 *ltc3589;
 467         int i, ret;
 468
 469         ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);
 470         if (!ltc3589)
 471                 return -ENOMEM;
 472
 473         i2c_set_clientdata(client, ltc3589);
 474         if (client->dev.of_node)
 475                 ltc3589->variant = (enum ltc3589_variant)
 476                         of_device_get_match_data(&client->dev);
 477         else
 478                 ltc3589->variant = id->driver_data;
 479         ltc3589->dev = dev;
 480
 481         descs = ltc3589->regulator_descs;
 482         memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));
 483         if (ltc3589->variant == LTC3589) {
 484                 descs[LTC3589_LDO3].desc.fixed_uV = 1800000;
 485                 descs[LTC3589_LDO4].desc.volt_table = ltc3589_ldo4;
 486         } else {
 487                 descs[LTC3589_LDO3].desc.fixed_uV = 2800000;
 488                 descs[LTC3589_LDO4].desc.volt_table = ltc3589_12_ldo4;
 489         }
 490
 491         ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);
 492         if (IS_ERR(ltc3589->regmap)) {
 493                 ret = PTR_ERR(ltc3589->regmap);
 494                 dev_err(dev, "failed to initialize regmap: %d\n", ret);
 495                 return ret;
 496         }
 497
 498         ret = ltc3589_parse_regulators_dt(ltc3589);
 499         if (ret)
 500                 return ret;
 501
 502         for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {
 503                 struct ltc3589_regulator *rdesc = &ltc3589->regulator_descs[i];
 504                 struct regulator_desc *desc = &rdesc->desc;
 505                 struct regulator_init_data *init_data;
 506                 struct regulator_config config = { };
 507
 508                 init_data = match_init_data(i);
 509
 510                 if (i < LTC3589_LDO3)
 511                         ltc3589_apply_fb_voltage_divider(rdesc);
 512
 513                 config.dev = dev;
 514                 config.init_data = init_data;
 515                 config.driver_data = ltc3589;
 516                 config.of_node = match_of_node(i);
 517
 518                 ltc3589->regulators[i] = devm_regulator_register(dev, desc,
 519                                                                  &config);
 520                 if (IS_ERR(ltc3589->regulators[i])) {
 521                         ret = PTR_ERR(ltc3589->regulators[i]);
 522                         dev_err(dev, "failed to register regulator %s: %d\n",
 523                                 desc->name, ret);
 524                         return ret;
 525                 }
 526         }
 527
 528         if (client->irq) {
 529                 ret = devm_request_threaded_irq(dev, client->irq, NULL,
 530                                                 ltc3589_isr,
 531                                                 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 532                                                 client->name, ltc3589);
 533                 if (ret) {
 534                         dev_err(dev, "Failed to request IRQ: %d\n", ret);
 535                         return ret;
 536                 }
 537         }
 538
 539         return 0;
 540 }
 541
 542 static struct i2c_device_id ltc3589_i2c_id[] = {
 543         { "ltc3589",   LTC3589   },
 544         { "ltc3589-1", LTC3589_1 },
 545         { "ltc3589-2", LTC3589_2 },
 546         { }
 547 };
 548 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);
 549
 550 static const struct of_device_id ltc3589_of_match[] = {
 551         {
 552                 .compatible = "lltc,ltc3589",
 553                 .data = (void *)LTC3589,
 554         },
 555         {
 556                 .compatible = "lltc,ltc3589-1",
 557                 .data = (void *)LTC3589_1,
 558         },
 559         {
 560                 .compatible = "lltc,ltc3589-2",
 561                 .data = (void *)LTC3589_2,
 562         },
 563         { },
 564 };
 565 MODULE_DEVICE_TABLE(of, ltc3589_of_match);
 566
 567 static struct i2c_driver ltc3589_driver = {
 568         .driver = {
 569                 .name = DRIVER_NAME,
 570                 .of_match_table = of_match_ptr(ltc3589_of_match),
 571         },
 572         .probe = ltc3589_probe,
 573         .id_table = ltc3589_i2c_id,
 574 };
 575 module_i2c_driver(ltc3589_driver);
 576
 577 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
 578 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");
 579 MODULE_LICENSE("GPL v2");