1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * RTC driver for the Micro Crystal RV3028 4 * 5 * Copyright (C) 2019 Micro Crystal SA 6 * 7 * Alexandre Belloni <alexandre.belloni@bootlin.com> 8 * 9 */ 10 11 #include <linux/clk-provider.h> 12 #include <linux/bcd.h> 13 #include <linux/bitfield.h> 14 #include <linux/bitops.h> 15 #include <linux/i2c.h> 16 #include <linux/interrupt.h> 17 #include <linux/kernel.h> 18 #include <linux/log2.h> 19 #include <linux/module.h> 20 #include <linux/of_device.h> 21 #include <linux/regmap.h> 22 #include <linux/rtc.h> 23 24 #define RV3028_SEC 0x00 25 #define RV3028_MIN 0x01 26 #define RV3028_HOUR 0x02 27 #define RV3028_WDAY 0x03 28 #define RV3028_DAY 0x04 29 #define RV3028_MONTH 0x05 30 #define RV3028_YEAR 0x06 31 #define RV3028_ALARM_MIN 0x07 32 #define RV3028_ALARM_HOUR 0x08 33 #define RV3028_ALARM_DAY 0x09 34 #define RV3028_STATUS 0x0E 35 #define RV3028_CTRL1 0x0F 36 #define RV3028_CTRL2 0x10 37 #define RV3028_EVT_CTRL 0x13 38 #define RV3028_TS_COUNT 0x14 39 #define RV3028_TS_SEC 0x15 40 #define RV3028_RAM1 0x1F 41 #define RV3028_EEPROM_ADDR 0x25 42 #define RV3028_EEPROM_DATA 0x26 43 #define RV3028_EEPROM_CMD 0x27 44 #define RV3028_CLKOUT 0x35 45 #define RV3028_OFFSET 0x36 46 #define RV3028_BACKUP 0x37 47 48 #define RV3028_STATUS_PORF BIT(0) 49 #define RV3028_STATUS_EVF BIT(1) 50 #define RV3028_STATUS_AF BIT(2) 51 #define RV3028_STATUS_TF BIT(3) 52 #define RV3028_STATUS_UF BIT(4) 53 #define RV3028_STATUS_BSF BIT(5) 54 #define RV3028_STATUS_CLKF BIT(6) 55 #define RV3028_STATUS_EEBUSY BIT(7) 56 57 #define RV3028_CLKOUT_FD_MASK GENMASK(2, 0) 58 #define RV3028_CLKOUT_PORIE BIT(3) 59 #define RV3028_CLKOUT_CLKSY BIT(6) 60 #define RV3028_CLKOUT_CLKOE BIT(7) 61 62 #define RV3028_CTRL1_EERD BIT(3) 63 #define RV3028_CTRL1_WADA BIT(5) 64 65 #define RV3028_CTRL2_RESET BIT(0) 66 #define RV3028_CTRL2_12_24 BIT(1) 67 #define RV3028_CTRL2_EIE BIT(2) 68 #define RV3028_CTRL2_AIE BIT(3) 69 #define RV3028_CTRL2_TIE BIT(4) 70 #define RV3028_CTRL2_UIE BIT(5) 71 #define RV3028_CTRL2_TSE BIT(7) 72 73 #define RV3028_EVT_CTRL_TSR BIT(2) 74 75 #define RV3028_EEPROM_CMD_UPDATE 0x11 76 #define RV3028_EEPROM_CMD_WRITE 0x21 77 #define RV3028_EEPROM_CMD_READ 0x22 78 79 #define RV3028_EEBUSY_POLL 10000 80 #define RV3028_EEBUSY_TIMEOUT 100000 81 82 #define RV3028_BACKUP_TCE BIT(5) 83 #define RV3028_BACKUP_TCR_MASK GENMASK(1,0) 84 #define RV3028_BACKUP_BSM GENMASK(3,2) 85 86 #define RV3028_BACKUP_BSM_DSM 0x1 87 #define RV3028_BACKUP_BSM_LSM 0x3 88 89 #define OFFSET_STEP_PPT 953674 90 91 enum rv3028_type { 92 rv_3028, 93 }; 94 95 struct rv3028_data { 96 struct regmap *regmap; 97 struct rtc_device *rtc; 98 enum rv3028_type type; 99 #ifdef CONFIG_COMMON_CLK 100 struct clk_hw clkout_hw; 101 #endif 102 }; 103 104 static u16 rv3028_trickle_resistors[] = {3000, 5000, 9000, 15000}; 105 106 static ssize_t timestamp0_store(struct device *dev, 107 struct device_attribute *attr, 108 const char *buf, size_t count) 109 { 110 struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); 111 112 regmap_update_bits(rv3028->regmap, RV3028_EVT_CTRL, RV3028_EVT_CTRL_TSR, 113 RV3028_EVT_CTRL_TSR); 114 115 return count; 116 }; 117 118 static ssize_t timestamp0_show(struct device *dev, 119 struct device_attribute *attr, char *buf) 120 { 121 struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); 122 struct rtc_time tm; 123 int ret, count; 124 u8 date[6]; 125 126 ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count); 127 if (ret) 128 return ret; 129 130 if (!count) 131 return 0; 132 133 ret = regmap_bulk_read(rv3028->regmap, RV3028_TS_SEC, date, 134 sizeof(date)); 135 if (ret) 136 return ret; 137 138 tm.tm_sec = bcd2bin(date[0]); 139 tm.tm_min = bcd2bin(date[1]); 140 tm.tm_hour = bcd2bin(date[2]); 141 tm.tm_mday = bcd2bin(date[3]); 142 tm.tm_mon = bcd2bin(date[4]) - 1; 143 tm.tm_year = bcd2bin(date[5]) + 100; 144 145 ret = rtc_valid_tm(&tm); 146 if (ret) 147 return ret; 148 149 return sprintf(buf, "%llu\n", 150 (unsigned long long)rtc_tm_to_time64(&tm)); 151 }; 152 153 static DEVICE_ATTR_RW(timestamp0); 154 155 static ssize_t timestamp0_count_show(struct device *dev, 156 struct device_attribute *attr, char *buf) 157 { 158 struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent); 159 int ret, count; 160 161 ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count); 162 if (ret) 163 return ret; 164 165 return sprintf(buf, "%u\n", count); 166 }; 167 168 static DEVICE_ATTR_RO(timestamp0_count); 169 170 static struct attribute *rv3028_attrs[] = { 171 &dev_attr_timestamp0.attr, 172 &dev_attr_timestamp0_count.attr, 173 NULL 174 }; 175 176 static const struct attribute_group rv3028_attr_group = { 177 .attrs = rv3028_attrs, 178 }; 179 180 static int rv3028_exit_eerd(struct rv3028_data *rv3028, u32 eerd) 181 { 182 if (eerd) 183 return 0; 184 185 return regmap_update_bits(rv3028->regmap, RV3028_CTRL1, RV3028_CTRL1_EERD, 0); 186 } 187 188 static int rv3028_enter_eerd(struct rv3028_data *rv3028, u32 *eerd) 189 { 190 u32 ctrl1, status; 191 int ret; 192 193 ret = regmap_read(rv3028->regmap, RV3028_CTRL1, &ctrl1); 194 if (ret) 195 return ret; 196 197 *eerd = ctrl1 & RV3028_CTRL1_EERD; 198 if (*eerd) 199 return 0; 200 201 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL1, 202 RV3028_CTRL1_EERD, RV3028_CTRL1_EERD); 203 if (ret) 204 return ret; 205 206 ret = regmap_read_poll_timeout(rv3028->regmap, RV3028_STATUS, status, 207 !(status & RV3028_STATUS_EEBUSY), 208 RV3028_EEBUSY_POLL, RV3028_EEBUSY_TIMEOUT); 209 if (ret) { 210 rv3028_exit_eerd(rv3028, *eerd); 211 212 return ret; 213 } 214 215 return 0; 216 } 217 218 static int rv3028_update_eeprom(struct rv3028_data *rv3028, u32 eerd) 219 { 220 u32 status; 221 int ret; 222 223 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, 0x0); 224 if (ret) 225 goto exit_eerd; 226 227 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, RV3028_EEPROM_CMD_UPDATE); 228 if (ret) 229 goto exit_eerd; 230 231 usleep_range(63000, RV3028_EEBUSY_TIMEOUT); 232 233 ret = regmap_read_poll_timeout(rv3028->regmap, RV3028_STATUS, status, 234 !(status & RV3028_STATUS_EEBUSY), 235 RV3028_EEBUSY_POLL, RV3028_EEBUSY_TIMEOUT); 236 237 exit_eerd: 238 rv3028_exit_eerd(rv3028, eerd); 239 240 return ret; 241 } 242 243 static int rv3028_update_cfg(struct rv3028_data *rv3028, unsigned int reg, 244 unsigned int mask, unsigned int val) 245 { 246 u32 eerd; 247 int ret; 248 249 ret = rv3028_enter_eerd(rv3028, &eerd); 250 if (ret) 251 return ret; 252 253 ret = regmap_update_bits(rv3028->regmap, reg, mask, val); 254 if (ret) { 255 rv3028_exit_eerd(rv3028, eerd); 256 return ret; 257 } 258 259 return rv3028_update_eeprom(rv3028, eerd); 260 } 261 262 static irqreturn_t rv3028_handle_irq(int irq, void *dev_id) 263 { 264 struct rv3028_data *rv3028 = dev_id; 265 unsigned long events = 0; 266 u32 status = 0, ctrl = 0; 267 268 if (regmap_read(rv3028->regmap, RV3028_STATUS, &status) < 0 || 269 status == 0) { 270 return IRQ_NONE; 271 } 272 273 status &= ~RV3028_STATUS_PORF; 274 275 if (status & RV3028_STATUS_TF) { 276 status |= RV3028_STATUS_TF; 277 ctrl |= RV3028_CTRL2_TIE; 278 events |= RTC_PF; 279 } 280 281 if (status & RV3028_STATUS_AF) { 282 status |= RV3028_STATUS_AF; 283 ctrl |= RV3028_CTRL2_AIE; 284 events |= RTC_AF; 285 } 286 287 if (status & RV3028_STATUS_UF) { 288 status |= RV3028_STATUS_UF; 289 ctrl |= RV3028_CTRL2_UIE; 290 events |= RTC_UF; 291 } 292 293 if (events) { 294 rtc_update_irq(rv3028->rtc, 1, events); 295 regmap_update_bits(rv3028->regmap, RV3028_STATUS, status, 0); 296 regmap_update_bits(rv3028->regmap, RV3028_CTRL2, ctrl, 0); 297 } 298 299 if (status & RV3028_STATUS_EVF) { 300 sysfs_notify(&rv3028->rtc->dev.kobj, NULL, 301 dev_attr_timestamp0.attr.name); 302 dev_warn(&rv3028->rtc->dev, "event detected"); 303 } 304 305 return IRQ_HANDLED; 306 } 307 308 static int rv3028_get_time(struct device *dev, struct rtc_time *tm) 309 { 310 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 311 u8 date[7]; 312 int ret, status; 313 314 ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); 315 if (ret < 0) 316 return ret; 317 318 if (status & RV3028_STATUS_PORF) 319 return -EINVAL; 320 321 ret = regmap_bulk_read(rv3028->regmap, RV3028_SEC, date, sizeof(date)); 322 if (ret) 323 return ret; 324 325 tm->tm_sec = bcd2bin(date[RV3028_SEC] & 0x7f); 326 tm->tm_min = bcd2bin(date[RV3028_MIN] & 0x7f); 327 tm->tm_hour = bcd2bin(date[RV3028_HOUR] & 0x3f); 328 tm->tm_wday = date[RV3028_WDAY] & 0x7f; 329 tm->tm_mday = bcd2bin(date[RV3028_DAY] & 0x3f); 330 tm->tm_mon = bcd2bin(date[RV3028_MONTH] & 0x1f) - 1; 331 tm->tm_year = bcd2bin(date[RV3028_YEAR]) + 100; 332 333 return 0; 334 } 335 336 static int rv3028_set_time(struct device *dev, struct rtc_time *tm) 337 { 338 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 339 u8 date[7]; 340 int ret; 341 342 date[RV3028_SEC] = bin2bcd(tm->tm_sec); 343 date[RV3028_MIN] = bin2bcd(tm->tm_min); 344 date[RV3028_HOUR] = bin2bcd(tm->tm_hour); 345 date[RV3028_WDAY] = tm->tm_wday; 346 date[RV3028_DAY] = bin2bcd(tm->tm_mday); 347 date[RV3028_MONTH] = bin2bcd(tm->tm_mon + 1); 348 date[RV3028_YEAR] = bin2bcd(tm->tm_year - 100); 349 350 /* 351 * Writing to the Seconds register has the same effect as setting RESET 352 * bit to 1 353 */ 354 ret = regmap_bulk_write(rv3028->regmap, RV3028_SEC, date, 355 sizeof(date)); 356 if (ret) 357 return ret; 358 359 ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, 360 RV3028_STATUS_PORF, 0); 361 362 return ret; 363 } 364 365 static int rv3028_get_alarm(struct device *dev, struct rtc_wkalrm *alrm) 366 { 367 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 368 u8 alarmvals[3]; 369 int status, ctrl, ret; 370 371 ret = regmap_bulk_read(rv3028->regmap, RV3028_ALARM_MIN, alarmvals, 372 sizeof(alarmvals)); 373 if (ret) 374 return ret; 375 376 ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); 377 if (ret < 0) 378 return ret; 379 380 ret = regmap_read(rv3028->regmap, RV3028_CTRL2, &ctrl); 381 if (ret < 0) 382 return ret; 383 384 alrm->time.tm_sec = 0; 385 alrm->time.tm_min = bcd2bin(alarmvals[0] & 0x7f); 386 alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); 387 alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f); 388 389 alrm->enabled = !!(ctrl & RV3028_CTRL2_AIE); 390 alrm->pending = (status & RV3028_STATUS_AF) && alrm->enabled; 391 392 return 0; 393 } 394 395 static int rv3028_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 396 { 397 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 398 u8 alarmvals[3]; 399 u8 ctrl = 0; 400 int ret; 401 402 /* The alarm has no seconds, round up to nearest minute */ 403 if (alrm->time.tm_sec) { 404 time64_t alarm_time = rtc_tm_to_time64(&alrm->time); 405 406 alarm_time += 60 - alrm->time.tm_sec; 407 rtc_time64_to_tm(alarm_time, &alrm->time); 408 } 409 410 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, 411 RV3028_CTRL2_AIE | RV3028_CTRL2_UIE, 0); 412 if (ret) 413 return ret; 414 415 alarmvals[0] = bin2bcd(alrm->time.tm_min); 416 alarmvals[1] = bin2bcd(alrm->time.tm_hour); 417 alarmvals[2] = bin2bcd(alrm->time.tm_mday); 418 419 ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, 420 RV3028_STATUS_AF, 0); 421 if (ret) 422 return ret; 423 424 ret = regmap_bulk_write(rv3028->regmap, RV3028_ALARM_MIN, alarmvals, 425 sizeof(alarmvals)); 426 if (ret) 427 return ret; 428 429 if (alrm->enabled) { 430 if (rv3028->rtc->uie_rtctimer.enabled) 431 ctrl |= RV3028_CTRL2_UIE; 432 if (rv3028->rtc->aie_timer.enabled) 433 ctrl |= RV3028_CTRL2_AIE; 434 } 435 436 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, 437 RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl); 438 439 return ret; 440 } 441 442 static int rv3028_alarm_irq_enable(struct device *dev, unsigned int enabled) 443 { 444 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 445 int ctrl = 0, ret; 446 447 if (enabled) { 448 if (rv3028->rtc->uie_rtctimer.enabled) 449 ctrl |= RV3028_CTRL2_UIE; 450 if (rv3028->rtc->aie_timer.enabled) 451 ctrl |= RV3028_CTRL2_AIE; 452 } 453 454 ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, 455 RV3028_STATUS_AF | RV3028_STATUS_UF, 0); 456 if (ret) 457 return ret; 458 459 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, 460 RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl); 461 if (ret) 462 return ret; 463 464 return 0; 465 } 466 467 static int rv3028_read_offset(struct device *dev, long *offset) 468 { 469 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 470 int ret, value, steps; 471 472 ret = regmap_read(rv3028->regmap, RV3028_OFFSET, &value); 473 if (ret < 0) 474 return ret; 475 476 steps = sign_extend32(value << 1, 8); 477 478 ret = regmap_read(rv3028->regmap, RV3028_BACKUP, &value); 479 if (ret < 0) 480 return ret; 481 482 steps += value >> 7; 483 484 *offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000); 485 486 return 0; 487 } 488 489 static int rv3028_set_offset(struct device *dev, long offset) 490 { 491 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 492 u32 eerd; 493 int ret; 494 495 offset = clamp(offset, -244141L, 243187L) * 1000; 496 offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT); 497 498 ret = rv3028_enter_eerd(rv3028, &eerd); 499 if (ret) 500 return ret; 501 502 ret = regmap_write(rv3028->regmap, RV3028_OFFSET, offset >> 1); 503 if (ret < 0) 504 goto exit_eerd; 505 506 ret = regmap_update_bits(rv3028->regmap, RV3028_BACKUP, BIT(7), 507 offset << 7); 508 if (ret < 0) 509 goto exit_eerd; 510 511 return rv3028_update_eeprom(rv3028, eerd); 512 513 exit_eerd: 514 rv3028_exit_eerd(rv3028, eerd); 515 516 return ret; 517 518 } 519 520 static int rv3028_param_get(struct device *dev, struct rtc_param *param) 521 { 522 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 523 int ret; 524 u32 value; 525 526 switch(param->param) { 527 case RTC_PARAM_BACKUP_SWITCH_MODE: 528 ret = regmap_read(rv3028->regmap, RV3028_BACKUP, &value); 529 if (ret < 0) 530 return ret; 531 532 value = FIELD_GET(RV3028_BACKUP_BSM, value); 533 534 switch(value) { 535 case RV3028_BACKUP_BSM_DSM: 536 param->uvalue = RTC_BSM_DIRECT; 537 break; 538 case RV3028_BACKUP_BSM_LSM: 539 param->uvalue = RTC_BSM_LEVEL; 540 break; 541 default: 542 param->uvalue = RTC_BSM_DISABLED; 543 } 544 break; 545 546 default: 547 return -EINVAL; 548 } 549 550 return 0; 551 } 552 553 static int rv3028_param_set(struct device *dev, struct rtc_param *param) 554 { 555 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 556 u8 mode; 557 558 switch(param->param) { 559 case RTC_PARAM_BACKUP_SWITCH_MODE: 560 switch (param->uvalue) { 561 case RTC_BSM_DISABLED: 562 mode = 0; 563 break; 564 case RTC_BSM_DIRECT: 565 mode = RV3028_BACKUP_BSM_DSM; 566 break; 567 case RTC_BSM_LEVEL: 568 mode = RV3028_BACKUP_BSM_LSM; 569 break; 570 default: 571 return -EINVAL; 572 } 573 574 return rv3028_update_cfg(rv3028, RV3028_BACKUP, RV3028_BACKUP_BSM, 575 FIELD_PREP(RV3028_BACKUP_BSM, mode)); 576 577 default: 578 return -EINVAL; 579 } 580 581 return 0; 582 } 583 584 static int rv3028_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 585 { 586 struct rv3028_data *rv3028 = dev_get_drvdata(dev); 587 int status, ret = 0; 588 589 switch (cmd) { 590 case RTC_VL_READ: 591 ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); 592 if (ret < 0) 593 return ret; 594 595 status = status & RV3028_STATUS_PORF ? RTC_VL_DATA_INVALID : 0; 596 return put_user(status, (unsigned int __user *)arg); 597 598 default: 599 return -ENOIOCTLCMD; 600 } 601 } 602 603 static int rv3028_nvram_write(void *priv, unsigned int offset, void *val, 604 size_t bytes) 605 { 606 return regmap_bulk_write(priv, RV3028_RAM1 + offset, val, bytes); 607 } 608 609 static int rv3028_nvram_read(void *priv, unsigned int offset, void *val, 610 size_t bytes) 611 { 612 return regmap_bulk_read(priv, RV3028_RAM1 + offset, val, bytes); 613 } 614 615 static int rv3028_eeprom_write(void *priv, unsigned int offset, void *val, 616 size_t bytes) 617 { 618 struct rv3028_data *rv3028 = priv; 619 u32 status, eerd; 620 int i, ret; 621 u8 *buf = val; 622 623 ret = rv3028_enter_eerd(rv3028, &eerd); 624 if (ret) 625 return ret; 626 627 for (i = 0; i < bytes; i++) { 628 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_ADDR, offset + i); 629 if (ret) 630 goto restore_eerd; 631 632 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_DATA, buf[i]); 633 if (ret) 634 goto restore_eerd; 635 636 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, 0x0); 637 if (ret) 638 goto restore_eerd; 639 640 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, 641 RV3028_EEPROM_CMD_WRITE); 642 if (ret) 643 goto restore_eerd; 644 645 usleep_range(RV3028_EEBUSY_POLL, RV3028_EEBUSY_TIMEOUT); 646 647 ret = regmap_read_poll_timeout(rv3028->regmap, RV3028_STATUS, status, 648 !(status & RV3028_STATUS_EEBUSY), 649 RV3028_EEBUSY_POLL, 650 RV3028_EEBUSY_TIMEOUT); 651 if (ret) 652 goto restore_eerd; 653 } 654 655 restore_eerd: 656 rv3028_exit_eerd(rv3028, eerd); 657 658 return ret; 659 } 660 661 static int rv3028_eeprom_read(void *priv, unsigned int offset, void *val, 662 size_t bytes) 663 { 664 struct rv3028_data *rv3028 = priv; 665 u32 status, eerd, data; 666 int i, ret; 667 u8 *buf = val; 668 669 ret = rv3028_enter_eerd(rv3028, &eerd); 670 if (ret) 671 return ret; 672 673 for (i = 0; i < bytes; i++) { 674 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_ADDR, offset + i); 675 if (ret) 676 goto restore_eerd; 677 678 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, 0x0); 679 if (ret) 680 goto restore_eerd; 681 682 ret = regmap_write(rv3028->regmap, RV3028_EEPROM_CMD, 683 RV3028_EEPROM_CMD_READ); 684 if (ret) 685 goto restore_eerd; 686 687 ret = regmap_read_poll_timeout(rv3028->regmap, RV3028_STATUS, status, 688 !(status & RV3028_STATUS_EEBUSY), 689 RV3028_EEBUSY_POLL, 690 RV3028_EEBUSY_TIMEOUT); 691 if (ret) 692 goto restore_eerd; 693 694 ret = regmap_read(rv3028->regmap, RV3028_EEPROM_DATA, &data); 695 if (ret) 696 goto restore_eerd; 697 buf[i] = data; 698 } 699 700 restore_eerd: 701 rv3028_exit_eerd(rv3028, eerd); 702 703 return ret; 704 } 705 706 #ifdef CONFIG_COMMON_CLK 707 #define clkout_hw_to_rv3028(hw) container_of(hw, struct rv3028_data, clkout_hw) 708 709 static int clkout_rates[] = { 710 32768, 711 8192, 712 1024, 713 64, 714 32, 715 1, 716 }; 717 718 static unsigned long rv3028_clkout_recalc_rate(struct clk_hw *hw, 719 unsigned long parent_rate) 720 { 721 int clkout, ret; 722 struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw); 723 724 ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout); 725 if (ret < 0) 726 return 0; 727 728 clkout &= RV3028_CLKOUT_FD_MASK; 729 return clkout_rates[clkout]; 730 } 731 732 static long rv3028_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 733 unsigned long *prate) 734 { 735 int i; 736 737 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 738 if (clkout_rates[i] <= rate) 739 return clkout_rates[i]; 740 741 return 0; 742 } 743 744 static int rv3028_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 745 unsigned long parent_rate) 746 { 747 int i, ret; 748 u32 enabled; 749 struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw); 750 751 ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &enabled); 752 if (ret < 0) 753 return ret; 754 755 ret = regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0); 756 if (ret < 0) 757 return ret; 758 759 enabled &= RV3028_CLKOUT_CLKOE; 760 761 for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) 762 if (clkout_rates[i] == rate) 763 return rv3028_update_cfg(rv3028, RV3028_CLKOUT, 0xff, 764 RV3028_CLKOUT_CLKSY | enabled | i); 765 766 return -EINVAL; 767 } 768 769 static int rv3028_clkout_prepare(struct clk_hw *hw) 770 { 771 struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw); 772 773 return regmap_write(rv3028->regmap, RV3028_CLKOUT, 774 RV3028_CLKOUT_CLKSY | RV3028_CLKOUT_CLKOE); 775 } 776 777 static void rv3028_clkout_unprepare(struct clk_hw *hw) 778 { 779 struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw); 780 781 regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0); 782 regmap_update_bits(rv3028->regmap, RV3028_STATUS, 783 RV3028_STATUS_CLKF, 0); 784 } 785 786 static int rv3028_clkout_is_prepared(struct clk_hw *hw) 787 { 788 int clkout, ret; 789 struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw); 790 791 ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout); 792 if (ret < 0) 793 return ret; 794 795 return !!(clkout & RV3028_CLKOUT_CLKOE); 796 } 797 798 static const struct clk_ops rv3028_clkout_ops = { 799 .prepare = rv3028_clkout_prepare, 800 .unprepare = rv3028_clkout_unprepare, 801 .is_prepared = rv3028_clkout_is_prepared, 802 .recalc_rate = rv3028_clkout_recalc_rate, 803 .round_rate = rv3028_clkout_round_rate, 804 .set_rate = rv3028_clkout_set_rate, 805 }; 806 807 static int rv3028_clkout_register_clk(struct rv3028_data *rv3028, 808 struct i2c_client *client) 809 { 810 int ret; 811 struct clk *clk; 812 struct clk_init_data init; 813 struct device_node *node = client->dev.of_node; 814 815 ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS, 816 RV3028_STATUS_CLKF, 0); 817 if (ret < 0) 818 return ret; 819 820 init.name = "rv3028-clkout"; 821 init.ops = &rv3028_clkout_ops; 822 init.flags = 0; 823 init.parent_names = NULL; 824 init.num_parents = 0; 825 rv3028->clkout_hw.init = &init; 826 827 /* optional override of the clockname */ 828 of_property_read_string(node, "clock-output-names", &init.name); 829 830 /* register the clock */ 831 clk = devm_clk_register(&client->dev, &rv3028->clkout_hw); 832 if (!IS_ERR(clk)) 833 of_clk_add_provider(node, of_clk_src_simple_get, clk); 834 835 return 0; 836 } 837 #endif 838 839 static const struct rtc_class_ops rv3028_rtc_ops = { 840 .read_time = rv3028_get_time, 841 .set_time = rv3028_set_time, 842 .read_alarm = rv3028_get_alarm, 843 .set_alarm = rv3028_set_alarm, 844 .alarm_irq_enable = rv3028_alarm_irq_enable, 845 .read_offset = rv3028_read_offset, 846 .set_offset = rv3028_set_offset, 847 .ioctl = rv3028_ioctl, 848 .param_get = rv3028_param_get, 849 .param_set = rv3028_param_set, 850 }; 851 852 static const struct regmap_config regmap_config = { 853 .reg_bits = 8, 854 .val_bits = 8, 855 .max_register = 0x37, 856 }; 857 858 static int rv3028_probe(struct i2c_client *client) 859 { 860 struct rv3028_data *rv3028; 861 int ret, status; 862 u32 ohms; 863 struct nvmem_config nvmem_cfg = { 864 .name = "rv3028_nvram", 865 .word_size = 1, 866 .stride = 1, 867 .size = 2, 868 .type = NVMEM_TYPE_BATTERY_BACKED, 869 .reg_read = rv3028_nvram_read, 870 .reg_write = rv3028_nvram_write, 871 }; 872 struct nvmem_config eeprom_cfg = { 873 .name = "rv3028_eeprom", 874 .word_size = 1, 875 .stride = 1, 876 .size = 43, 877 .type = NVMEM_TYPE_EEPROM, 878 .reg_read = rv3028_eeprom_read, 879 .reg_write = rv3028_eeprom_write, 880 }; 881 882 rv3028 = devm_kzalloc(&client->dev, sizeof(struct rv3028_data), 883 GFP_KERNEL); 884 if (!rv3028) 885 return -ENOMEM; 886 887 rv3028->regmap = devm_regmap_init_i2c(client, ®map_config); 888 if (IS_ERR(rv3028->regmap)) 889 return PTR_ERR(rv3028->regmap); 890 891 i2c_set_clientdata(client, rv3028); 892 893 ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status); 894 if (ret < 0) 895 return ret; 896 897 if (status & RV3028_STATUS_AF) 898 dev_warn(&client->dev, "An alarm may have been missed.\n"); 899 900 rv3028->rtc = devm_rtc_allocate_device(&client->dev); 901 if (IS_ERR(rv3028->rtc)) 902 return PTR_ERR(rv3028->rtc); 903 904 if (client->irq > 0) { 905 ret = devm_request_threaded_irq(&client->dev, client->irq, 906 NULL, rv3028_handle_irq, 907 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 908 "rv3028", rv3028); 909 if (ret) { 910 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n"); 911 client->irq = 0; 912 } 913 } 914 if (!client->irq) 915 clear_bit(RTC_FEATURE_ALARM, rv3028->rtc->features); 916 917 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL1, 918 RV3028_CTRL1_WADA, RV3028_CTRL1_WADA); 919 if (ret) 920 return ret; 921 922 /* setup timestamping */ 923 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2, 924 RV3028_CTRL2_EIE | RV3028_CTRL2_TSE, 925 RV3028_CTRL2_EIE | RV3028_CTRL2_TSE); 926 if (ret) 927 return ret; 928 929 /* setup trickle charger */ 930 if (!device_property_read_u32(&client->dev, "trickle-resistor-ohms", 931 &ohms)) { 932 int i; 933 934 for (i = 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++) 935 if (ohms == rv3028_trickle_resistors[i]) 936 break; 937 938 if (i < ARRAY_SIZE(rv3028_trickle_resistors)) { 939 ret = rv3028_update_cfg(rv3028, RV3028_BACKUP, RV3028_BACKUP_TCE | 940 RV3028_BACKUP_TCR_MASK, RV3028_BACKUP_TCE | i); 941 if (ret) 942 return ret; 943 } else { 944 dev_warn(&client->dev, "invalid trickle resistor value\n"); 945 } 946 } 947 948 ret = rtc_add_group(rv3028->rtc, &rv3028_attr_group); 949 if (ret) 950 return ret; 951 952 set_bit(RTC_FEATURE_BACKUP_SWITCH_MODE, rv3028->rtc->features); 953 954 rv3028->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; 955 rv3028->rtc->range_max = RTC_TIMESTAMP_END_2099; 956 rv3028->rtc->ops = &rv3028_rtc_ops; 957 ret = devm_rtc_register_device(rv3028->rtc); 958 if (ret) 959 return ret; 960 961 nvmem_cfg.priv = rv3028->regmap; 962 devm_rtc_nvmem_register(rv3028->rtc, &nvmem_cfg); 963 eeprom_cfg.priv = rv3028; 964 devm_rtc_nvmem_register(rv3028->rtc, &eeprom_cfg); 965 966 rv3028->rtc->max_user_freq = 1; 967 968 #ifdef CONFIG_COMMON_CLK 969 rv3028_clkout_register_clk(rv3028, client); 970 #endif 971 return 0; 972 } 973 974 static const __maybe_unused struct of_device_id rv3028_of_match[] = { 975 { .compatible = "microcrystal,rv3028", }, 976 { } 977 }; 978 MODULE_DEVICE_TABLE(of, rv3028_of_match); 979 980 static struct i2c_driver rv3028_driver = { 981 .driver = { 982 .name = "rtc-rv3028", 983 .of_match_table = of_match_ptr(rv3028_of_match), 984 }, 985 .probe_new = rv3028_probe, 986 }; 987 module_i2c_driver(rv3028_driver); 988 989 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>"); 990 MODULE_DESCRIPTION("Micro Crystal RV3028 RTC driver"); 991 MODULE_LICENSE("GPL v2"); 992