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/regmap.h> 26 #include <linux/regulator/driver.h> 27 #include <linux/regulator/of_regulator.h> 28 29 #define DRIVER_NAME "ltc3589" 30 31 #define LTC3589_IRQSTAT 0x02 32 #define LTC3589_SCR1 0x07 33 #define LTC3589_OVEN 0x10 34 #define LTC3589_SCR2 0x12 35 #define LTC3589_PGSTAT 0x13 36 #define LTC3589_VCCR 0x20 37 #define LTC3589_CLIRQ 0x21 38 #define LTC3589_B1DTV1 0x23 39 #define LTC3589_B1DTV2 0x24 40 #define LTC3589_VRRCR 0x25 41 #define LTC3589_B2DTV1 0x26 42 #define LTC3589_B2DTV2 0x27 43 #define LTC3589_B3DTV1 0x29 44 #define LTC3589_B3DTV2 0x2a 45 #define LTC3589_L2DTV1 0x32 46 #define LTC3589_L2DTV2 0x33 47 48 #define LTC3589_IRQSTAT_PGOOD_TIMEOUT BIT(3) 49 #define LTC3589_IRQSTAT_UNDERVOLT_WARN BIT(4) 50 #define LTC3589_IRQSTAT_UNDERVOLT_FAULT BIT(5) 51 #define LTC3589_IRQSTAT_THERMAL_WARN BIT(6) 52 #define LTC3589_IRQSTAT_THERMAL_FAULT BIT(7) 53 54 #define LTC3589_OVEN_SW1 BIT(0) 55 #define LTC3589_OVEN_SW2 BIT(1) 56 #define LTC3589_OVEN_SW3 BIT(2) 57 #define LTC3589_OVEN_BB_OUT BIT(3) 58 #define LTC3589_OVEN_LDO2 BIT(4) 59 #define LTC3589_OVEN_LDO3 BIT(5) 60 #define LTC3589_OVEN_LDO4 BIT(6) 61 #define LTC3589_OVEN_SW_CTRL BIT(7) 62 63 #define LTC3589_VCCR_SW1_GO BIT(0) 64 #define LTC3589_VCCR_SW2_GO BIT(2) 65 #define LTC3589_VCCR_SW3_GO BIT(4) 66 #define LTC3589_VCCR_LDO2_GO BIT(6) 67 68 enum ltc3589_variant { 69 LTC3589, 70 LTC3589_1, 71 LTC3589_2, 72 }; 73 74 enum ltc3589_reg { 75 LTC3589_SW1, 76 LTC3589_SW2, 77 LTC3589_SW3, 78 LTC3589_BB_OUT, 79 LTC3589_LDO1, 80 LTC3589_LDO2, 81 LTC3589_LDO3, 82 LTC3589_LDO4, 83 LTC3589_NUM_REGULATORS, 84 }; 85 86 struct ltc3589_regulator { 87 struct regulator_desc desc; 88 89 /* External feedback voltage divider */ 90 unsigned int r1; 91 unsigned int r2; 92 }; 93 94 struct ltc3589 { 95 struct regmap *regmap; 96 struct device *dev; 97 enum ltc3589_variant variant; 98 struct ltc3589_regulator regulator_descs[LTC3589_NUM_REGULATORS]; 99 struct regulator_dev *regulators[LTC3589_NUM_REGULATORS]; 100 }; 101 102 static const int ltc3589_ldo4[] = { 103 2800000, 2500000, 1800000, 3300000, 104 }; 105 106 static const int ltc3589_12_ldo4[] = { 107 1200000, 1800000, 2500000, 3200000, 108 }; 109 110 static int ltc3589_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay) 111 { 112 struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); 113 int sel, shift; 114 115 if (unlikely(ramp_delay <= 0)) 116 return -EINVAL; 117 118 /* VRRCR slew rate offsets are the same as VCCR go bit offsets */ 119 shift = ffs(rdev->desc->apply_bit) - 1; 120 121 /* The slew rate can be set to 0.88, 1.75, 3.5, or 7 mV/uS */ 122 for (sel = 0; sel < 4; sel++) { 123 if ((880 << sel) >= ramp_delay) { 124 return regmap_update_bits(ltc3589->regmap, 125 LTC3589_VRRCR, 126 0x3 << shift, sel << shift); 127 } 128 } 129 return -EINVAL; 130 } 131 132 static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV) 133 { 134 struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); 135 int sel; 136 137 sel = regulator_map_voltage_linear(rdev, uV, uV); 138 if (sel < 0) 139 return sel; 140 141 /* DTV2 register follows right after the corresponding DTV1 register */ 142 return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1, 143 rdev->desc->vsel_mask, sel); 144 } 145 146 static int ltc3589_set_suspend_mode(struct regulator_dev *rdev, 147 unsigned int mode) 148 { 149 struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); 150 int mask, bit = 0; 151 152 /* VCCR reference selects are right next to the VCCR go bits */ 153 mask = rdev->desc->apply_bit << 1; 154 155 if (mode == REGULATOR_MODE_STANDBY) 156 bit = mask; /* Select DTV2 */ 157 158 mask |= rdev->desc->apply_bit; 159 bit |= rdev->desc->apply_bit; 160 return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit); 161 } 162 163 /* SW1, SW2, SW3, LDO2 */ 164 static struct regulator_ops ltc3589_linear_regulator_ops = { 165 .enable = regulator_enable_regmap, 166 .disable = regulator_disable_regmap, 167 .is_enabled = regulator_is_enabled_regmap, 168 .list_voltage = regulator_list_voltage_linear, 169 .set_voltage_sel = regulator_set_voltage_sel_regmap, 170 .get_voltage_sel = regulator_get_voltage_sel_regmap, 171 .set_ramp_delay = ltc3589_set_ramp_delay, 172 .set_voltage_time_sel = regulator_set_voltage_time_sel, 173 .set_suspend_voltage = ltc3589_set_suspend_voltage, 174 .set_suspend_mode = ltc3589_set_suspend_mode, 175 }; 176 177 /* BB_OUT, LDO3 */ 178 static struct regulator_ops ltc3589_fixed_regulator_ops = { 179 .enable = regulator_enable_regmap, 180 .disable = regulator_disable_regmap, 181 .is_enabled = regulator_is_enabled_regmap, 182 }; 183 184 /* LDO1 */ 185 static struct regulator_ops ltc3589_fixed_standby_regulator_ops = { 186 }; 187 188 /* LDO4 */ 189 static struct regulator_ops ltc3589_table_regulator_ops = { 190 .enable = regulator_enable_regmap, 191 .disable = regulator_disable_regmap, 192 .is_enabled = regulator_is_enabled_regmap, 193 .list_voltage = regulator_list_voltage_table, 194 .set_voltage_sel = regulator_set_voltage_sel_regmap, 195 .get_voltage_sel = regulator_get_voltage_sel_regmap, 196 }; 197 198 199 #define LTC3589_REG(_name, _ops, en_bit, dtv1_reg, dtv_mask, go_bit) \ 200 [LTC3589_ ## _name] = { \ 201 .desc = { \ 202 .name = #_name, \ 203 .n_voltages = (dtv_mask) + 1, \ 204 .min_uV = (go_bit) ? 362500 : 0, \ 205 .uV_step = (go_bit) ? 12500 : 0, \ 206 .ramp_delay = (go_bit) ? 1750 : 0, \ 207 .fixed_uV = (dtv_mask) ? 0 : 800000, \ 208 .ops = <c3589_ ## _ops ## _regulator_ops, \ 209 .type = REGULATOR_VOLTAGE, \ 210 .id = LTC3589_ ## _name, \ 211 .owner = THIS_MODULE, \ 212 .vsel_reg = (dtv1_reg), \ 213 .vsel_mask = (dtv_mask), \ 214 .apply_reg = (go_bit) ? LTC3589_VCCR : 0, \ 215 .apply_bit = (go_bit), \ 216 .enable_reg = (en_bit) ? LTC3589_OVEN : 0, \ 217 .enable_mask = (en_bit), \ 218 }, \ 219 } 220 221 #define LTC3589_LINEAR_REG(_name, _dtv1) \ 222 LTC3589_REG(_name, linear, LTC3589_OVEN_ ## _name, \ 223 LTC3589_ ## _dtv1, 0x1f, \ 224 LTC3589_VCCR_ ## _name ## _GO) 225 226 #define LTC3589_FIXED_REG(_name) \ 227 LTC3589_REG(_name, fixed, LTC3589_OVEN_ ## _name, 0, 0, 0) 228 229 static struct ltc3589_regulator ltc3589_regulators[LTC3589_NUM_REGULATORS] = { 230 LTC3589_LINEAR_REG(SW1, B1DTV1), 231 LTC3589_LINEAR_REG(SW2, B2DTV1), 232 LTC3589_LINEAR_REG(SW3, B3DTV1), 233 LTC3589_FIXED_REG(BB_OUT), 234 LTC3589_REG(LDO1, fixed_standby, 0, 0, 0, 0), 235 LTC3589_LINEAR_REG(LDO2, L2DTV1), 236 LTC3589_FIXED_REG(LDO3), 237 LTC3589_REG(LDO4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60, 0), 238 }; 239 240 #ifdef CONFIG_OF 241 static struct of_regulator_match ltc3589_matches[LTC3589_NUM_REGULATORS] = { 242 { .name = "sw1", }, 243 { .name = "sw2", }, 244 { .name = "sw3", }, 245 { .name = "bb-out", }, 246 { .name = "ldo1", }, /* standby */ 247 { .name = "ldo2", }, 248 { .name = "ldo3", }, 249 { .name = "ldo4", }, 250 }; 251 252 static int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589) 253 { 254 struct device *dev = ltc3589->dev; 255 struct device_node *node; 256 int i, ret; 257 258 node = of_get_child_by_name(dev->of_node, "regulators"); 259 if (!node) { 260 dev_err(dev, "regulators node not found\n"); 261 return -EINVAL; 262 } 263 264 ret = of_regulator_match(dev, node, ltc3589_matches, 265 ARRAY_SIZE(ltc3589_matches)); 266 of_node_put(node); 267 if (ret < 0) { 268 dev_err(dev, "Error parsing regulator init data: %d\n", ret); 269 return ret; 270 } 271 if (ret != LTC3589_NUM_REGULATORS) { 272 dev_err(dev, "Only %d regulators described in device tree\n", 273 ret); 274 return -EINVAL; 275 } 276 277 /* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */ 278 for (i = 0; i < LTC3589_LDO3; i++) { 279 struct ltc3589_regulator *desc = <c3589->regulator_descs[i]; 280 struct device_node *np = ltc3589_matches[i].of_node; 281 u32 vdiv[2]; 282 283 ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", 284 vdiv, 2); 285 if (ret) { 286 dev_err(dev, "Failed to parse voltage divider: %d\n", 287 ret); 288 return ret; 289 } 290 291 desc->r1 = vdiv[0]; 292 desc->r2 = vdiv[1]; 293 } 294 295 return 0; 296 } 297 298 static inline struct regulator_init_data *match_init_data(int index) 299 { 300 return ltc3589_matches[index].init_data; 301 } 302 303 static inline struct device_node *match_of_node(int index) 304 { 305 return ltc3589_matches[index].of_node; 306 } 307 #else 308 static inline int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589) 309 { 310 return 0; 311 } 312 313 static inline struct regulator_init_data *match_init_data(int index) 314 { 315 return NULL; 316 } 317 318 static inline struct device_node *match_of_node(int index) 319 { 320 return NULL; 321 } 322 #endif 323 324 static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg) 325 { 326 switch (reg) { 327 case LTC3589_IRQSTAT: 328 case LTC3589_SCR1: 329 case LTC3589_OVEN: 330 case LTC3589_SCR2: 331 case LTC3589_VCCR: 332 case LTC3589_CLIRQ: 333 case LTC3589_B1DTV1: 334 case LTC3589_B1DTV2: 335 case LTC3589_VRRCR: 336 case LTC3589_B2DTV1: 337 case LTC3589_B2DTV2: 338 case LTC3589_B3DTV1: 339 case LTC3589_B3DTV2: 340 case LTC3589_L2DTV1: 341 case LTC3589_L2DTV2: 342 return true; 343 } 344 return false; 345 } 346 347 static bool ltc3589_readable_reg(struct device *dev, unsigned int reg) 348 { 349 switch (reg) { 350 case LTC3589_IRQSTAT: 351 case LTC3589_SCR1: 352 case LTC3589_OVEN: 353 case LTC3589_SCR2: 354 case LTC3589_PGSTAT: 355 case LTC3589_VCCR: 356 case LTC3589_B1DTV1: 357 case LTC3589_B1DTV2: 358 case LTC3589_VRRCR: 359 case LTC3589_B2DTV1: 360 case LTC3589_B2DTV2: 361 case LTC3589_B3DTV1: 362 case LTC3589_B3DTV2: 363 case LTC3589_L2DTV1: 364 case LTC3589_L2DTV2: 365 return true; 366 } 367 return false; 368 } 369 370 static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg) 371 { 372 switch (reg) { 373 case LTC3589_IRQSTAT: 374 case LTC3589_PGSTAT: 375 case LTC3589_VCCR: 376 return true; 377 } 378 return false; 379 } 380 381 static const struct reg_default ltc3589_reg_defaults[] = { 382 { LTC3589_SCR1, 0x00 }, 383 { LTC3589_OVEN, 0x00 }, 384 { LTC3589_SCR2, 0x00 }, 385 { LTC3589_VCCR, 0x00 }, 386 { LTC3589_B1DTV1, 0x19 }, 387 { LTC3589_B1DTV2, 0x19 }, 388 { LTC3589_VRRCR, 0xff }, 389 { LTC3589_B2DTV1, 0x19 }, 390 { LTC3589_B2DTV2, 0x19 }, 391 { LTC3589_B3DTV1, 0x19 }, 392 { LTC3589_B3DTV2, 0x19 }, 393 { LTC3589_L2DTV1, 0x19 }, 394 { LTC3589_L2DTV2, 0x19 }, 395 }; 396 397 static const struct regmap_config ltc3589_regmap_config = { 398 .reg_bits = 8, 399 .val_bits = 8, 400 .writeable_reg = ltc3589_writeable_reg, 401 .readable_reg = ltc3589_readable_reg, 402 .volatile_reg = ltc3589_volatile_reg, 403 .max_register = LTC3589_L2DTV2, 404 .reg_defaults = ltc3589_reg_defaults, 405 .num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults), 406 .use_single_rw = true, 407 .cache_type = REGCACHE_RBTREE, 408 }; 409 410 411 static irqreturn_t ltc3589_isr(int irq, void *dev_id) 412 { 413 struct ltc3589 *ltc3589 = dev_id; 414 unsigned int i, irqstat, event; 415 416 regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat); 417 418 if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) { 419 event = REGULATOR_EVENT_OVER_TEMP; 420 for (i = 0; i < LTC3589_NUM_REGULATORS; i++) 421 regulator_notifier_call_chain(ltc3589->regulators[i], 422 event, NULL); 423 } 424 425 if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) { 426 event = REGULATOR_EVENT_UNDER_VOLTAGE; 427 for (i = 0; i < LTC3589_NUM_REGULATORS; i++) 428 regulator_notifier_call_chain(ltc3589->regulators[i], 429 event, NULL); 430 } 431 432 /* Clear warning condition */ 433 regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0); 434 435 return IRQ_HANDLED; 436 } 437 438 static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2) 439 { 440 uint64_t tmp; 441 if (uV == 0) 442 return 0; 443 tmp = (uint64_t)uV * r1; 444 do_div(tmp, r2); 445 return uV + (unsigned int)tmp; 446 } 447 448 static void ltc3589_apply_fb_voltage_divider(struct ltc3589_regulator *rdesc) 449 { 450 struct regulator_desc *desc = &rdesc->desc; 451 452 if (!rdesc->r1 || !rdesc->r2) 453 return; 454 455 desc->min_uV = ltc3589_scale(desc->min_uV, rdesc->r1, rdesc->r2); 456 desc->uV_step = ltc3589_scale(desc->uV_step, rdesc->r1, rdesc->r2); 457 desc->fixed_uV = ltc3589_scale(desc->fixed_uV, rdesc->r1, rdesc->r2); 458 } 459 460 static int ltc3589_probe(struct i2c_client *client, 461 const struct i2c_device_id *id) 462 { 463 struct device *dev = &client->dev; 464 struct ltc3589_regulator *descs; 465 struct ltc3589 *ltc3589; 466 int i, ret; 467 468 ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL); 469 if (!ltc3589) 470 return -ENOMEM; 471 472 i2c_set_clientdata(client, ltc3589); 473 ltc3589->variant = id->driver_data; 474 ltc3589->dev = dev; 475 476 descs = ltc3589->regulator_descs; 477 memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators)); 478 if (ltc3589->variant == LTC3589) { 479 descs[LTC3589_LDO3].desc.fixed_uV = 1800000; 480 descs[LTC3589_LDO4].desc.volt_table = ltc3589_ldo4; 481 } else { 482 descs[LTC3589_LDO3].desc.fixed_uV = 2800000; 483 descs[LTC3589_LDO4].desc.volt_table = ltc3589_12_ldo4; 484 } 485 486 ltc3589->regmap = devm_regmap_init_i2c(client, <c3589_regmap_config); 487 if (IS_ERR(ltc3589->regmap)) { 488 ret = PTR_ERR(ltc3589->regmap); 489 dev_err(dev, "failed to initialize regmap: %d\n", ret); 490 return ret; 491 } 492 493 ret = ltc3589_parse_regulators_dt(ltc3589); 494 if (ret) 495 return ret; 496 497 for (i = 0; i < LTC3589_NUM_REGULATORS; i++) { 498 struct ltc3589_regulator *rdesc = <c3589->regulator_descs[i]; 499 struct regulator_desc *desc = &rdesc->desc; 500 struct regulator_init_data *init_data; 501 struct regulator_config config = { }; 502 503 init_data = match_init_data(i); 504 505 if (i < LTC3589_LDO3) 506 ltc3589_apply_fb_voltage_divider(rdesc); 507 508 config.dev = dev; 509 config.init_data = init_data; 510 config.driver_data = ltc3589; 511 config.of_node = match_of_node(i); 512 513 ltc3589->regulators[i] = devm_regulator_register(dev, desc, 514 &config); 515 if (IS_ERR(ltc3589->regulators[i])) { 516 ret = PTR_ERR(ltc3589->regulators[i]); 517 dev_err(dev, "failed to register regulator %s: %d\n", 518 desc->name, ret); 519 return ret; 520 } 521 } 522 523 ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3589_isr, 524 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 525 client->name, ltc3589); 526 if (ret) { 527 dev_err(dev, "Failed to request IRQ: %d\n", ret); 528 return ret; 529 } 530 531 return 0; 532 } 533 534 static struct i2c_device_id ltc3589_i2c_id[] = { 535 { "ltc3589", LTC3589 }, 536 { "ltc3589-1", LTC3589_1 }, 537 { "ltc3589-2", LTC3589_2 }, 538 { } 539 }; 540 MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id); 541 542 static struct i2c_driver ltc3589_driver = { 543 .driver = { 544 .name = DRIVER_NAME, 545 }, 546 .probe = ltc3589_probe, 547 .id_table = ltc3589_i2c_id, 548 }; 549 module_i2c_driver(ltc3589_driver); 550 551 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>"); 552 MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)"); 553 MODULE_LICENSE("GPL v2"); 554