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1// SPDX-License-Identifier: GPL-2.02/*3 * RTC driver for the Micro Crystal RV30284 *5 * Copyright (C) 2019 Micro Crystal SA6 *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.h>21#include <linux/regmap.h>22#include <linux/rtc.h>23 24#define RV3028_SEC 0x0025#define RV3028_MIN 0x0126#define RV3028_HOUR 0x0227#define RV3028_WDAY 0x0328#define RV3028_DAY 0x0429#define RV3028_MONTH 0x0530#define RV3028_YEAR 0x0631#define RV3028_ALARM_MIN 0x0732#define RV3028_ALARM_HOUR 0x0833#define RV3028_ALARM_DAY 0x0934#define RV3028_STATUS 0x0E35#define RV3028_CTRL1 0x0F36#define RV3028_CTRL2 0x1037#define RV3028_EVT_CTRL 0x1338#define RV3028_TS_COUNT 0x1439#define RV3028_TS_SEC 0x1540#define RV3028_RAM1 0x1F41#define RV3028_EEPROM_ADDR 0x2542#define RV3028_EEPROM_DATA 0x2643#define RV3028_EEPROM_CMD 0x2744#define RV3028_CLKOUT 0x3545#define RV3028_OFFSET 0x3646#define RV3028_BACKUP 0x3747 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 0x1176#define RV3028_EEPROM_CMD_WRITE 0x2177#define RV3028_EEPROM_CMD_READ 0x2278 79#define RV3028_EEBUSY_POLL 1000080#define RV3028_EEBUSY_TIMEOUT 10000081 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 0x187#define RV3028_BACKUP_BSM_LSM 0x388 89#define OFFSET_STEP_PPT 95367490 91enum rv3028_type {92 rv_3028,93};94 95struct rv3028_data {96 struct regmap *regmap;97 struct rtc_device *rtc;98 enum rv3028_type type;99#ifdef CONFIG_COMMON_CLK100 struct clk_hw clkout_hw;101#endif102};103 104static u16 rv3028_trickle_resistors[] = {3000, 5000, 9000, 15000};105 106static 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 118static 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 153static DEVICE_ATTR_RW(timestamp0);154 155static 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 168static DEVICE_ATTR_RO(timestamp0_count);169 170static struct attribute *rv3028_attrs[] = {171 &dev_attr_timestamp0.attr,172 &dev_attr_timestamp0_count.attr,173 NULL174};175 176static const struct attribute_group rv3028_attr_group = {177 .attrs = rv3028_attrs,178};179 180static 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 188static 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 218static 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 237exit_eerd:238 rv3028_exit_eerd(rv3028, eerd);239 240 return ret;241}242 243static 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 262static 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 308static 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 336static 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 RESET352 * bit to 1353 */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 365static 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 395static 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 442static 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 467static 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 489static 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 513exit_eerd:514 rv3028_exit_eerd(rv3028, eerd);515 516 return ret;517 518}519 520static 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 553static 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 584static 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 603static 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 609static 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 615static 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 655restore_eerd:656 rv3028_exit_eerd(rv3028, eerd);657 658 return ret;659}660 661static 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 700restore_eerd:701 rv3028_exit_eerd(rv3028, eerd);702 703 return ret;704}705 706#ifdef CONFIG_COMMON_CLK707#define clkout_hw_to_rv3028(hw) container_of(hw, struct rv3028_data, clkout_hw)708 709static int clkout_rates[] = {710 32768,711 8192,712 1024,713 64,714 32,715 1,716};717 718static 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 732static 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 744static 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 769static 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 777static 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 786static 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 798static 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 807static 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#endif838 839static 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 852static const struct regmap_config regmap_config = {853 .reg_bits = 8,854 .val_bits = 8,855 .max_register = 0x37,856};857 858static u8 rv3028_set_trickle_charger(struct rv3028_data *rv3028,859 struct i2c_client *client)860{861 int ret, val_old, val;862 u32 ohms, chargeable;863 864 ret = regmap_read(rv3028->regmap, RV3028_BACKUP, &val_old);865 if (ret < 0)866 return ret;867 868 /* mask out only trickle charger bits */869 val_old = val_old & (RV3028_BACKUP_TCE | RV3028_BACKUP_TCR_MASK);870 val = val_old;871 872 /* setup trickle charger */873 if (!device_property_read_u32(&client->dev, "trickle-resistor-ohms",874 &ohms)) {875 int i;876 877 for (i = 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++)878 if (ohms == rv3028_trickle_resistors[i])879 break;880 881 if (i < ARRAY_SIZE(rv3028_trickle_resistors)) {882 /* enable trickle charger and its resistor */883 val = RV3028_BACKUP_TCE | i;884 } else {885 dev_warn(&client->dev, "invalid trickle resistor value\n");886 }887 }888 889 if (!device_property_read_u32(&client->dev, "aux-voltage-chargeable",890 &chargeable)) {891 switch (chargeable) {892 case 0:893 val &= ~RV3028_BACKUP_TCE;894 break;895 case 1:896 val |= RV3028_BACKUP_TCE;897 break;898 default:899 dev_warn(&client->dev,900 "unsupported aux-voltage-chargeable value\n");901 break;902 }903 }904 905 /* only update EEPROM if changes are necessary */906 if (val_old != val) {907 ret = rv3028_update_cfg(rv3028, RV3028_BACKUP, RV3028_BACKUP_TCE |908 RV3028_BACKUP_TCR_MASK, val);909 if (ret)910 return ret;911 }912 913 return ret;914}915 916static int rv3028_probe(struct i2c_client *client)917{918 struct rv3028_data *rv3028;919 int ret, status;920 struct nvmem_config nvmem_cfg = {921 .name = "rv3028_nvram",922 .word_size = 1,923 .stride = 1,924 .size = 2,925 .type = NVMEM_TYPE_BATTERY_BACKED,926 .reg_read = rv3028_nvram_read,927 .reg_write = rv3028_nvram_write,928 };929 struct nvmem_config eeprom_cfg = {930 .name = "rv3028_eeprom",931 .word_size = 1,932 .stride = 1,933 .size = 43,934 .type = NVMEM_TYPE_EEPROM,935 .reg_read = rv3028_eeprom_read,936 .reg_write = rv3028_eeprom_write,937 };938 939 rv3028 = devm_kzalloc(&client->dev, sizeof(struct rv3028_data),940 GFP_KERNEL);941 if (!rv3028)942 return -ENOMEM;943 944 rv3028->regmap = devm_regmap_init_i2c(client, ®map_config);945 if (IS_ERR(rv3028->regmap))946 return PTR_ERR(rv3028->regmap);947 948 i2c_set_clientdata(client, rv3028);949 950 ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status);951 if (ret < 0)952 return ret;953 954 if (status & RV3028_STATUS_AF)955 dev_warn(&client->dev, "An alarm may have been missed.\n");956 957 rv3028->rtc = devm_rtc_allocate_device(&client->dev);958 if (IS_ERR(rv3028->rtc))959 return PTR_ERR(rv3028->rtc);960 961 if (client->irq > 0) {962 unsigned long flags;963 964 /*965 * If flags = 0, devm_request_threaded_irq() will use IRQ flags966 * obtained from device tree.967 */968 if (dev_fwnode(&client->dev))969 flags = 0;970 else971 flags = IRQF_TRIGGER_LOW;972 973 ret = devm_request_threaded_irq(&client->dev, client->irq,974 NULL, rv3028_handle_irq,975 flags | IRQF_ONESHOT,976 "rv3028", rv3028);977 if (ret) {978 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");979 client->irq = 0;980 }981 }982 if (!client->irq)983 clear_bit(RTC_FEATURE_ALARM, rv3028->rtc->features);984 985 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL1,986 RV3028_CTRL1_WADA, RV3028_CTRL1_WADA);987 if (ret)988 return ret;989 990 /* setup timestamping */991 ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2,992 RV3028_CTRL2_EIE | RV3028_CTRL2_TSE,993 RV3028_CTRL2_EIE | RV3028_CTRL2_TSE);994 if (ret)995 return ret;996 997 ret = rv3028_set_trickle_charger(rv3028, client);998 if (ret)999 return ret;1000 1001 ret = rtc_add_group(rv3028->rtc, &rv3028_attr_group);1002 if (ret)1003 return ret;1004 1005 set_bit(RTC_FEATURE_BACKUP_SWITCH_MODE, rv3028->rtc->features);1006 1007 rv3028->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;1008 rv3028->rtc->range_max = RTC_TIMESTAMP_END_2099;1009 rv3028->rtc->ops = &rv3028_rtc_ops;1010 ret = devm_rtc_register_device(rv3028->rtc);1011 if (ret)1012 return ret;1013 1014 nvmem_cfg.priv = rv3028->regmap;1015 devm_rtc_nvmem_register(rv3028->rtc, &nvmem_cfg);1016 eeprom_cfg.priv = rv3028;1017 devm_rtc_nvmem_register(rv3028->rtc, &eeprom_cfg);1018 1019 rv3028->rtc->max_user_freq = 1;1020 1021#ifdef CONFIG_COMMON_CLK1022 rv3028_clkout_register_clk(rv3028, client);1023#endif1024 return 0;1025}1026 1027static const struct acpi_device_id rv3028_i2c_acpi_match[] = {1028 { "MCRY3028" },1029 { }1030};1031MODULE_DEVICE_TABLE(acpi, rv3028_i2c_acpi_match);1032 1033static const __maybe_unused struct of_device_id rv3028_of_match[] = {1034 { .compatible = "microcrystal,rv3028", },1035 { }1036};1037MODULE_DEVICE_TABLE(of, rv3028_of_match);1038 1039static const struct i2c_device_id rv3028_id_table[] = {1040 { .name = "rv3028", },1041 { }1042};1043MODULE_DEVICE_TABLE(i2c, rv3028_id_table);1044 1045static struct i2c_driver rv3028_driver = {1046 .driver = {1047 .name = "rtc-rv3028",1048 .acpi_match_table = rv3028_i2c_acpi_match,1049 .of_match_table = of_match_ptr(rv3028_of_match),1050 },1051 .id_table = rv3028_id_table,1052 .probe = rv3028_probe,1053};1054module_i2c_driver(rv3028_driver);1055 1056MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");1057MODULE_DESCRIPTION("Micro Crystal RV3028 RTC driver");1058MODULE_LICENSE("GPL v2");1059