drivers/rtc/rtc-rv3032.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * RTC driver for the Micro Crystal RV3032
   4  *
   5  * Copyright (C) 2020 Micro Crystal SA
   6  *
   7  * Alexandre Belloni <alexandre.belloni@bootlin.com>
   8  *
   9  */
  10
  11 #include <linux/clk.h>
  12 #include <linux/clk-provider.h>
  13 #include <linux/bcd.h>
  14 #include <linux/bitfield.h>
  15 #include <linux/bitops.h>
  16 #include <linux/hwmon.h>
  17 #include <linux/i2c.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/kernel.h>
  20 #include <linux/log2.h>
  21 #include <linux/module.h>
  22 #include <linux/of_device.h>
  23 #include <linux/regmap.h>
  24 #include <linux/rtc.h>
  25
  26 #define RV3032_SEC                      0x01
  27 #define RV3032_MIN                      0x02
  28 #define RV3032_HOUR                     0x03
  29 #define RV3032_WDAY                     0x04
  30 #define RV3032_DAY                      0x05
  31 #define RV3032_MONTH                    0x06
  32 #define RV3032_YEAR                     0x07
  33 #define RV3032_ALARM_MIN                0x08
  34 #define RV3032_ALARM_HOUR               0x09
  35 #define RV3032_ALARM_DAY                0x0A
  36 #define RV3032_STATUS                   0x0D
  37 #define RV3032_TLSB                     0x0E
  38 #define RV3032_TMSB                     0x0F
  39 #define RV3032_CTRL1                    0x10
  40 #define RV3032_CTRL2                    0x11
  41 #define RV3032_CTRL3                    0x12
  42 #define RV3032_TS_CTRL                  0x13
  43 #define RV3032_CLK_IRQ                  0x14
  44 #define RV3032_EEPROM_ADDR              0x3D
  45 #define RV3032_EEPROM_DATA              0x3E
  46 #define RV3032_EEPROM_CMD               0x3F
  47 #define RV3032_RAM1                     0x40
  48 #define RV3032_PMU                      0xC0
  49 #define RV3032_OFFSET                   0xC1
  50 #define RV3032_CLKOUT1                  0xC2
  51 #define RV3032_CLKOUT2                  0xC3
  52 #define RV3032_TREF0                    0xC4
  53 #define RV3032_TREF1                    0xC5
  54
  55 #define RV3032_STATUS_VLF               BIT(0)
  56 #define RV3032_STATUS_PORF              BIT(1)
  57 #define RV3032_STATUS_EVF               BIT(2)
  58 #define RV3032_STATUS_AF                BIT(3)
  59 #define RV3032_STATUS_TF                BIT(4)
  60 #define RV3032_STATUS_UF                BIT(5)
  61 #define RV3032_STATUS_TLF               BIT(6)
  62 #define RV3032_STATUS_THF               BIT(7)
  63
  64 #define RV3032_TLSB_CLKF                BIT(1)
  65 #define RV3032_TLSB_EEBUSY              BIT(2)
  66 #define RV3032_TLSB_TEMP                GENMASK(7, 4)
  67
  68 #define RV3032_CLKOUT2_HFD_MSK          GENMASK(4, 0)
  69 #define RV3032_CLKOUT2_FD_MSK           GENMASK(6, 5)
  70 #define RV3032_CLKOUT2_OS               BIT(7)
  71
  72 #define RV3032_CTRL1_EERD               BIT(3)
  73 #define RV3032_CTRL1_WADA               BIT(5)
  74
  75 #define RV3032_CTRL2_STOP               BIT(0)
  76 #define RV3032_CTRL2_EIE                BIT(2)
  77 #define RV3032_CTRL2_AIE                BIT(3)
  78 #define RV3032_CTRL2_TIE                BIT(4)
  79 #define RV3032_CTRL2_UIE                BIT(5)
  80 #define RV3032_CTRL2_CLKIE              BIT(6)
  81 #define RV3032_CTRL2_TSE                BIT(7)
  82
  83 #define RV3032_PMU_TCM                  GENMASK(1, 0)
  84 #define RV3032_PMU_TCR                  GENMASK(3, 2)
  85 #define RV3032_PMU_BSM                  GENMASK(5, 4)
  86 #define RV3032_PMU_NCLKE                BIT(6)
  87
  88 #define RV3032_PMU_BSM_DSM              1
  89 #define RV3032_PMU_BSM_LSM              2
  90
  91 #define RV3032_OFFSET_MSK               GENMASK(5, 0)
  92
  93 #define RV3032_EVT_CTRL_TSR             BIT(2)
  94
  95 #define RV3032_EEPROM_CMD_UPDATE        0x11
  96 #define RV3032_EEPROM_CMD_WRITE         0x21
  97 #define RV3032_EEPROM_CMD_READ          0x22
  98
  99 #define RV3032_EEPROM_USER              0xCB
 100
 101 #define RV3032_EEBUSY_POLL              10000
 102 #define RV3032_EEBUSY_TIMEOUT           100000
 103
 104 #define OFFSET_STEP_PPT                 238419
 105
 106 struct rv3032_data {
 107         struct regmap *regmap;
 108         struct rtc_device *rtc;
 109 #ifdef CONFIG_COMMON_CLK
 110         struct clk_hw clkout_hw;
 111 #endif
 112 };
 113
 114 static u16 rv3032_trickle_resistors[] = {1000, 2000, 7000, 11000};
 115 static u16 rv3032_trickle_voltages[] = {0, 1750, 3000, 4400};
 116
 117 static int rv3032_exit_eerd(struct rv3032_data *rv3032, u32 eerd)
 118 {
 119         if (eerd)
 120                 return 0;
 121
 122         return regmap_update_bits(rv3032->regmap, RV3032_CTRL1, RV3032_CTRL1_EERD, 0);
 123 }
 124
 125 static int rv3032_enter_eerd(struct rv3032_data *rv3032, u32 *eerd)
 126 {
 127         u32 ctrl1, status;
 128         int ret;
 129
 130         ret = regmap_read(rv3032->regmap, RV3032_CTRL1, &ctrl1);
 131         if (ret)
 132                 return ret;
 133
 134         *eerd = ctrl1 & RV3032_CTRL1_EERD;
 135         if (*eerd)
 136                 return 0;
 137
 138         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL1,
 139                                  RV3032_CTRL1_EERD, RV3032_CTRL1_EERD);
 140         if (ret)
 141                 return ret;
 142
 143         ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
 144                                        !(status & RV3032_TLSB_EEBUSY),
 145                                        RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 146         if (ret) {
 147                 rv3032_exit_eerd(rv3032, *eerd);
 148
 149                 return ret;
 150         }
 151
 152         return 0;
 153 }
 154
 155 static int rv3032_update_cfg(struct rv3032_data *rv3032, unsigned int reg,
 156                              unsigned int mask, unsigned int val)
 157 {
 158         u32 status, eerd;
 159         int ret;
 160
 161         ret = rv3032_enter_eerd(rv3032, &eerd);
 162         if (ret)
 163                 return ret;
 164
 165         ret = regmap_update_bits(rv3032->regmap, reg, mask, val);
 166         if (ret)
 167                 goto exit_eerd;
 168
 169         ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD, RV3032_EEPROM_CMD_UPDATE);
 170         if (ret)
 171                 goto exit_eerd;
 172
 173         usleep_range(46000, RV3032_EEBUSY_TIMEOUT);
 174
 175         ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
 176                                        !(status & RV3032_TLSB_EEBUSY),
 177                                        RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 178
 179 exit_eerd:
 180         rv3032_exit_eerd(rv3032, eerd);
 181
 182         return ret;
 183 }
 184
 185 static irqreturn_t rv3032_handle_irq(int irq, void *dev_id)
 186 {
 187         struct rv3032_data *rv3032 = dev_id;
 188         unsigned long events = 0;
 189         u32 status = 0, ctrl = 0;
 190
 191         if (regmap_read(rv3032->regmap, RV3032_STATUS, &status) < 0 ||
 192             status == 0) {
 193                 return IRQ_NONE;
 194         }
 195
 196         if (status & RV3032_STATUS_TF) {
 197                 status |= RV3032_STATUS_TF;
 198                 ctrl |= RV3032_CTRL2_TIE;
 199                 events |= RTC_PF;
 200         }
 201
 202         if (status & RV3032_STATUS_AF) {
 203                 status |= RV3032_STATUS_AF;
 204                 ctrl |= RV3032_CTRL2_AIE;
 205                 events |= RTC_AF;
 206         }
 207
 208         if (status & RV3032_STATUS_UF) {
 209                 status |= RV3032_STATUS_UF;
 210                 ctrl |= RV3032_CTRL2_UIE;
 211                 events |= RTC_UF;
 212         }
 213
 214         if (events) {
 215                 rtc_update_irq(rv3032->rtc, 1, events);
 216                 regmap_update_bits(rv3032->regmap, RV3032_STATUS, status, 0);
 217                 regmap_update_bits(rv3032->regmap, RV3032_CTRL2, ctrl, 0);
 218         }
 219
 220         return IRQ_HANDLED;
 221 }
 222
 223 static int rv3032_get_time(struct device *dev, struct rtc_time *tm)
 224 {
 225         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 226         u8 date[7];
 227         int ret, status;
 228
 229         ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
 230         if (ret < 0)
 231                 return ret;
 232
 233         if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
 234                 return -EINVAL;
 235
 236         ret = regmap_bulk_read(rv3032->regmap, RV3032_SEC, date, sizeof(date));
 237         if (ret)
 238                 return ret;
 239
 240         tm->tm_sec  = bcd2bin(date[0] & 0x7f);
 241         tm->tm_min  = bcd2bin(date[1] & 0x7f);
 242         tm->tm_hour = bcd2bin(date[2] & 0x3f);
 243         tm->tm_wday = date[3] & 0x7;
 244         tm->tm_mday = bcd2bin(date[4] & 0x3f);
 245         tm->tm_mon  = bcd2bin(date[5] & 0x1f) - 1;
 246         tm->tm_year = bcd2bin(date[6]) + 100;
 247
 248         return 0;
 249 }
 250
 251 static int rv3032_set_time(struct device *dev, struct rtc_time *tm)
 252 {
 253         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 254         u8 date[7];
 255         int ret;
 256
 257         date[0] = bin2bcd(tm->tm_sec);
 258         date[1] = bin2bcd(tm->tm_min);
 259         date[2] = bin2bcd(tm->tm_hour);
 260         date[3] = tm->tm_wday;
 261         date[4] = bin2bcd(tm->tm_mday);
 262         date[5] = bin2bcd(tm->tm_mon + 1);
 263         date[6] = bin2bcd(tm->tm_year - 100);
 264
 265         ret = regmap_bulk_write(rv3032->regmap, RV3032_SEC, date,
 266                                 sizeof(date));
 267         if (ret)
 268                 return ret;
 269
 270         ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
 271                                  RV3032_STATUS_PORF | RV3032_STATUS_VLF, 0);
 272
 273         return ret;
 274 }
 275
 276 static int rv3032_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 277 {
 278         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 279         u8 alarmvals[3];
 280         int status, ctrl, ret;
 281
 282         ret = regmap_bulk_read(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
 283                                sizeof(alarmvals));
 284         if (ret)
 285                 return ret;
 286
 287         ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
 288         if (ret < 0)
 289                 return ret;
 290
 291         ret = regmap_read(rv3032->regmap, RV3032_CTRL2, &ctrl);
 292         if (ret < 0)
 293                 return ret;
 294
 295         alrm->time.tm_sec  = 0;
 296         alrm->time.tm_min  = bcd2bin(alarmvals[0] & 0x7f);
 297         alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
 298         alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f);
 299
 300         alrm->enabled = !!(ctrl & RV3032_CTRL2_AIE);
 301         alrm->pending = (status & RV3032_STATUS_AF) && alrm->enabled;
 302
 303         return 0;
 304 }
 305
 306 static int rv3032_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 307 {
 308         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 309         u8 alarmvals[3];
 310         u8 ctrl = 0;
 311         int ret;
 312
 313         /* The alarm has no seconds, round up to nearest minute */
 314         if (alrm->time.tm_sec) {
 315                 time64_t alarm_time = rtc_tm_to_time64(&alrm->time);
 316
 317                 alarm_time += 60 - alrm->time.tm_sec;
 318                 rtc_time64_to_tm(alarm_time, &alrm->time);
 319         }
 320
 321         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
 322                                  RV3032_CTRL2_AIE | RV3032_CTRL2_UIE, 0);
 323         if (ret)
 324                 return ret;
 325
 326         alarmvals[0] = bin2bcd(alrm->time.tm_min);
 327         alarmvals[1] = bin2bcd(alrm->time.tm_hour);
 328         alarmvals[2] = bin2bcd(alrm->time.tm_mday);
 329
 330         ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
 331                                  RV3032_STATUS_AF, 0);
 332         if (ret)
 333                 return ret;
 334
 335         ret = regmap_bulk_write(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
 336                                 sizeof(alarmvals));
 337         if (ret)
 338                 return ret;
 339
 340         if (alrm->enabled) {
 341                 if (rv3032->rtc->uie_rtctimer.enabled)
 342                         ctrl |= RV3032_CTRL2_UIE;
 343                 if (rv3032->rtc->aie_timer.enabled)
 344                         ctrl |= RV3032_CTRL2_AIE;
 345         }
 346
 347         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
 348                                  RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
 349
 350         return ret;
 351 }
 352
 353 static int rv3032_alarm_irq_enable(struct device *dev, unsigned int enabled)
 354 {
 355         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 356         int ctrl = 0, ret;
 357
 358         if (enabled) {
 359                 if (rv3032->rtc->uie_rtctimer.enabled)
 360                         ctrl |= RV3032_CTRL2_UIE;
 361                 if (rv3032->rtc->aie_timer.enabled)
 362                         ctrl |= RV3032_CTRL2_AIE;
 363         }
 364
 365         ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
 366                                  RV3032_STATUS_AF | RV3032_STATUS_UF, 0);
 367         if (ret)
 368                 return ret;
 369
 370         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
 371                                  RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
 372         if (ret)
 373                 return ret;
 374
 375         return 0;
 376 }
 377
 378 static int rv3032_read_offset(struct device *dev, long *offset)
 379 {
 380         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 381         int ret, value, steps;
 382
 383         ret = regmap_read(rv3032->regmap, RV3032_OFFSET, &value);
 384         if (ret < 0)
 385                 return ret;
 386
 387         steps = sign_extend32(FIELD_GET(RV3032_OFFSET_MSK, value), 5);
 388
 389         *offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000);
 390
 391         return 0;
 392 }
 393
 394 static int rv3032_set_offset(struct device *dev, long offset)
 395 {
 396         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 397
 398         offset = clamp(offset, -7629L, 7391L) * 1000;
 399         offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT);
 400
 401         return rv3032_update_cfg(rv3032, RV3032_OFFSET, RV3032_OFFSET_MSK,
 402                                  FIELD_PREP(RV3032_OFFSET_MSK, offset));
 403 }
 404
 405 static int rv3032_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 406 {
 407         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 408         int status, val = 0, ret = 0;
 409
 410         switch (cmd) {
 411         case RTC_VL_READ:
 412                 ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
 413                 if (ret < 0)
 414                         return ret;
 415
 416                 if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
 417                         val = RTC_VL_DATA_INVALID;
 418                 return put_user(val, (unsigned int __user *)arg);
 419
 420         default:
 421                 return -ENOIOCTLCMD;
 422         }
 423 }
 424
 425 static int rv3032_nvram_write(void *priv, unsigned int offset, void *val, size_t bytes)
 426 {
 427         return regmap_bulk_write(priv, RV3032_RAM1 + offset, val, bytes);
 428 }
 429
 430 static int rv3032_nvram_read(void *priv, unsigned int offset, void *val, size_t bytes)
 431 {
 432         return regmap_bulk_read(priv, RV3032_RAM1 + offset, val, bytes);
 433 }
 434
 435 static int rv3032_eeprom_write(void *priv, unsigned int offset, void *val, size_t bytes)
 436 {
 437         struct rv3032_data *rv3032 = priv;
 438         u32 status, eerd;
 439         int i, ret;
 440         u8 *buf = val;
 441
 442         ret = rv3032_enter_eerd(rv3032, &eerd);
 443         if (ret)
 444                 return ret;
 445
 446         for (i = 0; i < bytes; i++) {
 447                 ret = regmap_write(rv3032->regmap, RV3032_EEPROM_ADDR,
 448                                    RV3032_EEPROM_USER + offset + i);
 449                 if (ret)
 450                         goto exit_eerd;
 451
 452                 ret = regmap_write(rv3032->regmap, RV3032_EEPROM_DATA, buf[i]);
 453                 if (ret)
 454                         goto exit_eerd;
 455
 456                 ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD,
 457                                    RV3032_EEPROM_CMD_WRITE);
 458                 if (ret)
 459                         goto exit_eerd;
 460
 461                 usleep_range(RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 462
 463                 ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
 464                                                !(status & RV3032_TLSB_EEBUSY),
 465                                                RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 466                 if (ret)
 467                         goto exit_eerd;
 468         }
 469
 470 exit_eerd:
 471         rv3032_exit_eerd(rv3032, eerd);
 472
 473         return ret;
 474 }
 475
 476 static int rv3032_eeprom_read(void *priv, unsigned int offset, void *val, size_t bytes)
 477 {
 478         struct rv3032_data *rv3032 = priv;
 479         u32 status, eerd, data;
 480         int i, ret;
 481         u8 *buf = val;
 482
 483         ret = rv3032_enter_eerd(rv3032, &eerd);
 484         if (ret)
 485                 return ret;
 486
 487         for (i = 0; i < bytes; i++) {
 488                 ret = regmap_write(rv3032->regmap, RV3032_EEPROM_ADDR,
 489                                    RV3032_EEPROM_USER + offset + i);
 490                 if (ret)
 491                         goto exit_eerd;
 492
 493                 ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD,
 494                                    RV3032_EEPROM_CMD_READ);
 495                 if (ret)
 496                         goto exit_eerd;
 497
 498                 ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
 499                                                !(status & RV3032_TLSB_EEBUSY),
 500                                                RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 501                 if (ret)
 502                         goto exit_eerd;
 503
 504                 ret = regmap_read(rv3032->regmap, RV3032_EEPROM_DATA, &data);
 505                 if (ret)
 506                         goto exit_eerd;
 507                 buf[i] = data;
 508         }
 509
 510 exit_eerd:
 511         rv3032_exit_eerd(rv3032, eerd);
 512
 513         return ret;
 514 }
 515
 516 static int rv3032_trickle_charger_setup(struct device *dev, struct rv3032_data *rv3032)
 517 {
 518         u32 val, ohms, voltage;
 519         int i;
 520
 521         val = FIELD_PREP(RV3032_PMU_TCM, 1) | FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_DSM);
 522         if (!device_property_read_u32(dev, "trickle-voltage-millivolt", &voltage)) {
 523                 for (i = 0; i < ARRAY_SIZE(rv3032_trickle_voltages); i++)
 524                         if (voltage == rv3032_trickle_voltages[i])
 525                                 break;
 526                 if (i < ARRAY_SIZE(rv3032_trickle_voltages))
 527                         val = FIELD_PREP(RV3032_PMU_TCM, i) |
 528                               FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_LSM);
 529         }
 530
 531         if (device_property_read_u32(dev, "trickle-resistor-ohms", &ohms))
 532                 return 0;
 533
 534         for (i = 0; i < ARRAY_SIZE(rv3032_trickle_resistors); i++)
 535                 if (ohms == rv3032_trickle_resistors[i])
 536                         break;
 537
 538         if (i >= ARRAY_SIZE(rv3032_trickle_resistors)) {
 539                 dev_warn(dev, "invalid trickle resistor value\n");
 540
 541                 return 0;
 542         }
 543
 544         return rv3032_update_cfg(rv3032, RV3032_PMU,
 545                                  RV3032_PMU_TCR | RV3032_PMU_TCM | RV3032_PMU_BSM,
 546                                  val | FIELD_PREP(RV3032_PMU_TCR, i));
 547 }
 548
 549 #ifdef CONFIG_COMMON_CLK
 550 #define clkout_hw_to_rv3032(hw) container_of(hw, struct rv3032_data, clkout_hw)
 551
 552 static int clkout_xtal_rates[] = {
 553         32768,
 554         1024,
 555         64,
 556         1,
 557 };
 558
 559 #define RV3032_HFD_STEP 8192
 560
 561 static unsigned long rv3032_clkout_recalc_rate(struct clk_hw *hw,
 562                                                unsigned long parent_rate)
 563 {
 564         int clkout, ret;
 565         struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
 566
 567         ret = regmap_read(rv3032->regmap, RV3032_CLKOUT2, &clkout);
 568         if (ret < 0)
 569                 return 0;
 570
 571         if (clkout & RV3032_CLKOUT2_OS) {
 572                 unsigned long rate = FIELD_GET(RV3032_CLKOUT2_HFD_MSK, clkout) << 8;
 573
 574                 ret = regmap_read(rv3032->regmap, RV3032_CLKOUT1, &clkout);
 575                 if (ret < 0)
 576                         return 0;
 577
 578                 rate += clkout + 1;
 579
 580                 return rate * RV3032_HFD_STEP;
 581         }
 582
 583         return clkout_xtal_rates[FIELD_GET(RV3032_CLKOUT2_FD_MSK, clkout)];
 584 }
 585
 586 static long rv3032_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
 587                                      unsigned long *prate)
 588 {
 589         int i, hfd;
 590
 591         if (rate < RV3032_HFD_STEP)
 592                 for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++)
 593                         if (clkout_xtal_rates[i] <= rate)
 594                                 return clkout_xtal_rates[i];
 595
 596         hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
 597
 598         return RV3032_HFD_STEP * clamp(hfd, 0, 8192);
 599 }
 600
 601 static int rv3032_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
 602                                   unsigned long parent_rate)
 603 {
 604         struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
 605         u32 status, eerd;
 606         int i, hfd, ret;
 607
 608         for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++) {
 609                 if (clkout_xtal_rates[i] == rate) {
 610                         return rv3032_update_cfg(rv3032, RV3032_CLKOUT2, 0xff,
 611                                                  FIELD_PREP(RV3032_CLKOUT2_FD_MSK, i));
 612                 }
 613         }
 614
 615         hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
 616         hfd = clamp(hfd, 1, 8192) - 1;
 617
 618         ret = rv3032_enter_eerd(rv3032, &eerd);
 619         if (ret)
 620                 goto exit_eerd;
 621
 622         ret = regmap_write(rv3032->regmap, RV3032_CLKOUT1, hfd & 0xff);
 623         if (ret)
 624                 return ret;
 625
 626         ret = regmap_write(rv3032->regmap, RV3032_CLKOUT2, RV3032_CLKOUT2_OS |
 627                             FIELD_PREP(RV3032_CLKOUT2_HFD_MSK, hfd >> 8));
 628         if (ret)
 629                 goto exit_eerd;
 630
 631         ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD, RV3032_EEPROM_CMD_UPDATE);
 632         if (ret)
 633                 goto exit_eerd;
 634
 635         usleep_range(46000, RV3032_EEBUSY_TIMEOUT);
 636
 637         ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
 638                                        !(status & RV3032_TLSB_EEBUSY),
 639                                        RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
 640
 641 exit_eerd:
 642         rv3032_exit_eerd(rv3032, eerd);
 643
 644         return ret;
 645 }
 646
 647 static int rv3032_clkout_prepare(struct clk_hw *hw)
 648 {
 649         struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
 650
 651         return rv3032_update_cfg(rv3032, RV3032_PMU, RV3032_PMU_NCLKE, 0);
 652 }
 653
 654 static void rv3032_clkout_unprepare(struct clk_hw *hw)
 655 {
 656         struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
 657
 658         rv3032_update_cfg(rv3032, RV3032_PMU, RV3032_PMU_NCLKE, RV3032_PMU_NCLKE);
 659 }
 660
 661 static int rv3032_clkout_is_prepared(struct clk_hw *hw)
 662 {
 663         int val, ret;
 664         struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
 665
 666         ret = regmap_read(rv3032->regmap, RV3032_PMU, &val);
 667         if (ret < 0)
 668                 return ret;
 669
 670         return !(val & RV3032_PMU_NCLKE);
 671 }
 672
 673 static const struct clk_ops rv3032_clkout_ops = {
 674         .prepare = rv3032_clkout_prepare,
 675         .unprepare = rv3032_clkout_unprepare,
 676         .is_prepared = rv3032_clkout_is_prepared,
 677         .recalc_rate = rv3032_clkout_recalc_rate,
 678         .round_rate = rv3032_clkout_round_rate,
 679         .set_rate = rv3032_clkout_set_rate,
 680 };
 681
 682 static int rv3032_clkout_register_clk(struct rv3032_data *rv3032,
 683                                       struct i2c_client *client)
 684 {
 685         int ret;
 686         struct clk *clk;
 687         struct clk_init_data init;
 688         struct device_node *node = client->dev.of_node;
 689
 690         ret = regmap_update_bits(rv3032->regmap, RV3032_TLSB, RV3032_TLSB_CLKF, 0);
 691         if (ret < 0)
 692                 return ret;
 693
 694         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2, RV3032_CTRL2_CLKIE, 0);
 695         if (ret < 0)
 696                 return ret;
 697
 698         ret = regmap_write(rv3032->regmap, RV3032_CLK_IRQ, 0);
 699         if (ret < 0)
 700                 return ret;
 701
 702         init.name = "rv3032-clkout";
 703         init.ops = &rv3032_clkout_ops;
 704         init.flags = 0;
 705         init.parent_names = NULL;
 706         init.num_parents = 0;
 707         rv3032->clkout_hw.init = &init;
 708
 709         of_property_read_string(node, "clock-output-names", &init.name);
 710
 711         clk = devm_clk_register(&client->dev, &rv3032->clkout_hw);
 712         if (!IS_ERR(clk))
 713                 of_clk_add_provider(node, of_clk_src_simple_get, clk);
 714
 715         return 0;
 716 }
 717 #endif
 718
 719 static int rv3032_hwmon_read_temp(struct device *dev, long *mC)
 720 {
 721         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 722         u8 buf[2];
 723         int temp, prev = 0;
 724         int ret;
 725
 726         ret = regmap_bulk_read(rv3032->regmap, RV3032_TLSB, buf, sizeof(buf));
 727         if (ret)
 728                 return ret;
 729
 730         temp = sign_extend32(buf[1], 7) << 4;
 731         temp |= FIELD_GET(RV3032_TLSB_TEMP, buf[0]);
 732
 733         /* No blocking or shadowing on RV3032_TLSB and RV3032_TMSB */
 734         do {
 735                 prev = temp;
 736
 737                 ret = regmap_bulk_read(rv3032->regmap, RV3032_TLSB, buf, sizeof(buf));
 738                 if (ret)
 739                         return ret;
 740
 741                 temp = sign_extend32(buf[1], 7) << 4;
 742                 temp |= FIELD_GET(RV3032_TLSB_TEMP, buf[0]);
 743         } while (temp != prev);
 744
 745         *mC = (temp * 1000) / 16;
 746
 747         return 0;
 748 }
 749
 750 static umode_t rv3032_hwmon_is_visible(const void *data, enum hwmon_sensor_types type,
 751                                        u32 attr, int channel)
 752 {
 753         if (type != hwmon_temp)
 754                 return 0;
 755
 756         switch (attr) {
 757         case hwmon_temp_input:
 758                 return 0444;
 759         default:
 760                 return 0;
 761         }
 762 }
 763
 764 static int rv3032_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
 765                              u32 attr, int channel, long *temp)
 766 {
 767         int err;
 768
 769         switch (attr) {
 770         case hwmon_temp_input:
 771                 err = rv3032_hwmon_read_temp(dev, temp);
 772                 break;
 773         default:
 774                 err = -EOPNOTSUPP;
 775                 break;
 776         }
 777
 778         return err;
 779 }
 780
 781 static const struct hwmon_channel_info *rv3032_hwmon_info[] = {
 782         HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
 783         HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
 784         NULL
 785 };
 786
 787 static const struct hwmon_ops rv3032_hwmon_hwmon_ops = {
 788         .is_visible = rv3032_hwmon_is_visible,
 789         .read = rv3032_hwmon_read,
 790 };
 791
 792 static const struct hwmon_chip_info rv3032_hwmon_chip_info = {
 793         .ops = &rv3032_hwmon_hwmon_ops,
 794         .info = rv3032_hwmon_info,
 795 };
 796
 797 static void rv3032_hwmon_register(struct device *dev)
 798 {
 799         struct rv3032_data *rv3032 = dev_get_drvdata(dev);
 800
 801         if (!IS_REACHABLE(CONFIG_HWMON))
 802                 return;
 803
 804         devm_hwmon_device_register_with_info(dev, "rv3032", rv3032, &rv3032_hwmon_chip_info, NULL);
 805 }
 806
 807 static struct rtc_class_ops rv3032_rtc_ops = {
 808         .read_time = rv3032_get_time,
 809         .set_time = rv3032_set_time,
 810         .read_offset = rv3032_read_offset,
 811         .set_offset = rv3032_set_offset,
 812         .ioctl = rv3032_ioctl,
 813 };
 814
 815 static const struct regmap_config regmap_config = {
 816         .reg_bits = 8,
 817         .val_bits = 8,
 818         .max_register = 0xCA,
 819 };
 820
 821 static int rv3032_probe(struct i2c_client *client)
 822 {
 823         struct rv3032_data *rv3032;
 824         int ret, status;
 825         struct nvmem_config nvmem_cfg = {
 826                 .name = "rv3032_nvram",
 827                 .word_size = 1,
 828                 .stride = 1,
 829                 .size = 16,
 830                 .type = NVMEM_TYPE_BATTERY_BACKED,
 831                 .reg_read = rv3032_nvram_read,
 832                 .reg_write = rv3032_nvram_write,
 833         };
 834         struct nvmem_config eeprom_cfg = {
 835                 .name = "rv3032_eeprom",
 836                 .word_size = 1,
 837                 .stride = 1,
 838                 .size = 32,
 839                 .type = NVMEM_TYPE_EEPROM,
 840                 .reg_read = rv3032_eeprom_read,
 841                 .reg_write = rv3032_eeprom_write,
 842         };
 843
 844         rv3032 = devm_kzalloc(&client->dev, sizeof(struct rv3032_data),
 845                               GFP_KERNEL);
 846         if (!rv3032)
 847                 return -ENOMEM;
 848
 849         rv3032->regmap = devm_regmap_init_i2c(client, &regmap_config);
 850         if (IS_ERR(rv3032->regmap))
 851                 return PTR_ERR(rv3032->regmap);
 852
 853         i2c_set_clientdata(client, rv3032);
 854
 855         ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
 856         if (ret < 0)
 857                 return ret;
 858
 859         rv3032->rtc = devm_rtc_allocate_device(&client->dev);
 860         if (IS_ERR(rv3032->rtc))
 861                 return PTR_ERR(rv3032->rtc);
 862
 863         if (client->irq > 0) {
 864                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 865                                                 NULL, rv3032_handle_irq,
 866                                                 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 867                                                 "rv3032", rv3032);
 868                 if (ret) {
 869                         dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
 870                         client->irq = 0;
 871                 } else {
 872                         rv3032_rtc_ops.read_alarm = rv3032_get_alarm;
 873                         rv3032_rtc_ops.set_alarm = rv3032_set_alarm;
 874                         rv3032_rtc_ops.alarm_irq_enable = rv3032_alarm_irq_enable;
 875                 }
 876         }
 877
 878         ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL1,
 879                                  RV3032_CTRL1_WADA, RV3032_CTRL1_WADA);
 880         if (ret)
 881                 return ret;
 882
 883         rv3032_trickle_charger_setup(&client->dev, rv3032);
 884
 885         rv3032->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 886         rv3032->rtc->range_max = RTC_TIMESTAMP_END_2099;
 887         rv3032->rtc->ops = &rv3032_rtc_ops;
 888         ret = devm_rtc_register_device(rv3032->rtc);
 889         if (ret)
 890                 return ret;
 891
 892         nvmem_cfg.priv = rv3032->regmap;
 893         devm_rtc_nvmem_register(rv3032->rtc, &nvmem_cfg);
 894         eeprom_cfg.priv = rv3032;
 895         devm_rtc_nvmem_register(rv3032->rtc, &eeprom_cfg);
 896
 897         rv3032->rtc->max_user_freq = 1;
 898
 899 #ifdef CONFIG_COMMON_CLK
 900         rv3032_clkout_register_clk(rv3032, client);
 901 #endif
 902
 903         rv3032_hwmon_register(&client->dev);
 904
 905         return 0;
 906 }
 907
 908 static const struct of_device_id rv3032_of_match[] = {
 909         { .compatible = "microcrystal,rv3032", },
 910         { }
 911 };
 912 MODULE_DEVICE_TABLE(of, rv3032_of_match);
 913
 914 static struct i2c_driver rv3032_driver = {
 915         .driver = {
 916                 .name = "rtc-rv3032",
 917                 .of_match_table = of_match_ptr(rv3032_of_match),
 918         },
 919         .probe_new      = rv3032_probe,
 920 };
 921 module_i2c_driver(rv3032_driver);
 922
 923 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
 924 MODULE_DESCRIPTION("Micro Crystal RV3032 RTC driver");
 925 MODULE_LICENSE("GPL v2");