drivers/rtc/rtc-rv3029c2.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Micro Crystal RV-3029 / RV-3049 rtc class driver
   4  *
   5  * Author: Gregory Hermant <gregory.hermant@calao-systems.com>
   6  *         Michael Buesch <m@bues.ch>
   7  *
   8  * based on previously existing rtc class drivers
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/i2c.h>
  13 #include <linux/spi/spi.h>
  14 #include <linux/bcd.h>
  15 #include <linux/rtc.h>
  16 #include <linux/delay.h>
  17 #include <linux/of.h>
  18 #include <linux/hwmon.h>
  19 #include <linux/hwmon-sysfs.h>
  20 #include <linux/kstrtox.h>
  21 #include <linux/regmap.h>
  22
  23 /* Register map */
  24 /* control section */
  25 #define RV3029_ONOFF_CTRL               0x00
  26 #define RV3029_ONOFF_CTRL_WE            BIT(0)
  27 #define RV3029_ONOFF_CTRL_TE            BIT(1)
  28 #define RV3029_ONOFF_CTRL_TAR           BIT(2)
  29 #define RV3029_ONOFF_CTRL_EERE          BIT(3)
  30 #define RV3029_ONOFF_CTRL_SRON          BIT(4)
  31 #define RV3029_ONOFF_CTRL_TD0           BIT(5)
  32 #define RV3029_ONOFF_CTRL_TD1           BIT(6)
  33 #define RV3029_ONOFF_CTRL_CLKINT        BIT(7)
  34 #define RV3029_IRQ_CTRL                 0x01
  35 #define RV3029_IRQ_CTRL_AIE             BIT(0)
  36 #define RV3029_IRQ_CTRL_TIE             BIT(1)
  37 #define RV3029_IRQ_CTRL_V1IE            BIT(2)
  38 #define RV3029_IRQ_CTRL_V2IE            BIT(3)
  39 #define RV3029_IRQ_CTRL_SRIE            BIT(4)
  40 #define RV3029_IRQ_FLAGS                0x02
  41 #define RV3029_IRQ_FLAGS_AF             BIT(0)
  42 #define RV3029_IRQ_FLAGS_TF             BIT(1)
  43 #define RV3029_IRQ_FLAGS_V1IF           BIT(2)
  44 #define RV3029_IRQ_FLAGS_V2IF           BIT(3)
  45 #define RV3029_IRQ_FLAGS_SRF            BIT(4)
  46 #define RV3029_STATUS                   0x03
  47 #define RV3029_STATUS_VLOW1             BIT(2)
  48 #define RV3029_STATUS_VLOW2             BIT(3)
  49 #define RV3029_STATUS_SR                BIT(4)
  50 #define RV3029_STATUS_PON               BIT(5)
  51 #define RV3029_STATUS_EEBUSY            BIT(7)
  52 #define RV3029_RST_CTRL                 0x04
  53 #define RV3029_RST_CTRL_SYSR            BIT(4)
  54 #define RV3029_CONTROL_SECTION_LEN      0x05
  55
  56 /* watch section */
  57 #define RV3029_W_SEC                    0x08
  58 #define RV3029_W_MINUTES                0x09
  59 #define RV3029_W_HOURS                  0x0A
  60 #define RV3029_REG_HR_12_24             BIT(6) /* 24h/12h mode */
  61 #define RV3029_REG_HR_PM                BIT(5) /* PM/AM bit in 12h mode */
  62 #define RV3029_W_DATE                   0x0B
  63 #define RV3029_W_DAYS                   0x0C
  64 #define RV3029_W_MONTHS                 0x0D
  65 #define RV3029_W_YEARS                  0x0E
  66 #define RV3029_WATCH_SECTION_LEN        0x07
  67
  68 /* alarm section */
  69 #define RV3029_A_SC                     0x10
  70 #define RV3029_A_MN                     0x11
  71 #define RV3029_A_HR                     0x12
  72 #define RV3029_A_DT                     0x13
  73 #define RV3029_A_DW                     0x14
  74 #define RV3029_A_MO                     0x15
  75 #define RV3029_A_YR                     0x16
  76 #define RV3029_A_AE_X                   BIT(7)
  77 #define RV3029_ALARM_SECTION_LEN        0x07
  78
  79 /* timer section */
  80 #define RV3029_TIMER_LOW                0x18
  81 #define RV3029_TIMER_HIGH               0x19
  82
  83 /* temperature section */
  84 #define RV3029_TEMP_PAGE                0x20
  85
  86 /* eeprom data section */
  87 #define RV3029_E2P_EEDATA1              0x28
  88 #define RV3029_E2P_EEDATA2              0x29
  89 #define RV3029_E2PDATA_SECTION_LEN      0x02
  90
  91 /* eeprom control section */
  92 #define RV3029_CONTROL_E2P_EECTRL       0x30
  93 #define RV3029_EECTRL_THP               BIT(0) /* temp scan interval */
  94 #define RV3029_EECTRL_THE               BIT(1) /* thermometer enable */
  95 #define RV3029_EECTRL_FD0               BIT(2) /* CLKOUT */
  96 #define RV3029_EECTRL_FD1               BIT(3) /* CLKOUT */
  97 #define RV3029_TRICKLE_1K               BIT(4) /* 1.5K resistance */
  98 #define RV3029_TRICKLE_5K               BIT(5) /* 5K   resistance */
  99 #define RV3029_TRICKLE_20K              BIT(6) /* 20K  resistance */
 100 #define RV3029_TRICKLE_80K              BIT(7) /* 80K  resistance */
 101 #define RV3029_TRICKLE_MASK             (RV3029_TRICKLE_1K |\
 102                                          RV3029_TRICKLE_5K |\
 103                                          RV3029_TRICKLE_20K |\
 104                                          RV3029_TRICKLE_80K)
 105 #define RV3029_TRICKLE_SHIFT            4
 106 #define RV3029_CONTROL_E2P_XOFFS        0x31 /* XTAL offset */
 107 #define RV3029_CONTROL_E2P_XOFFS_SIGN   BIT(7) /* Sign: 1->pos, 0->neg */
 108 #define RV3029_CONTROL_E2P_QCOEF        0x32 /* XTAL temp drift coef */
 109 #define RV3029_CONTROL_E2P_TURNOVER     0x33 /* XTAL turnover temp (in *C) */
 110 #define RV3029_CONTROL_E2P_TOV_MASK     0x3F /* XTAL turnover temp mask */
 111
 112 /* user ram section */
 113 #define RV3029_RAM_PAGE                 0x38
 114 #define RV3029_RAM_SECTION_LEN          8
 115
 116 struct rv3029_data {
 117         struct device           *dev;
 118         struct rtc_device       *rtc;
 119         struct regmap           *regmap;
 120         int irq;
 121 };
 122
 123 static int rv3029_eeprom_busywait(struct rv3029_data *rv3029)
 124 {
 125         unsigned int sr;
 126         int i, ret;
 127
 128         for (i = 100; i > 0; i--) {
 129                 ret = regmap_read(rv3029->regmap, RV3029_STATUS, &sr);
 130                 if (ret < 0)
 131                         break;
 132                 if (!(sr & RV3029_STATUS_EEBUSY))
 133                         break;
 134                 usleep_range(1000, 10000);
 135         }
 136         if (i <= 0) {
 137                 dev_err(rv3029->dev, "EEPROM busy wait timeout.\n");
 138                 return -ETIMEDOUT;
 139         }
 140
 141         return ret;
 142 }
 143
 144 static int rv3029_eeprom_exit(struct rv3029_data *rv3029)
 145 {
 146         /* Re-enable eeprom refresh */
 147         return regmap_update_bits(rv3029->regmap, RV3029_ONOFF_CTRL,
 148                                   RV3029_ONOFF_CTRL_EERE,
 149                                   RV3029_ONOFF_CTRL_EERE);
 150 }
 151
 152 static int rv3029_eeprom_enter(struct rv3029_data *rv3029)
 153 {
 154         unsigned int sr;
 155         int ret;
 156
 157         /* Check whether we are in the allowed voltage range. */
 158         ret = regmap_read(rv3029->regmap, RV3029_STATUS, &sr);
 159         if (ret < 0)
 160                 return ret;
 161         if (sr & RV3029_STATUS_VLOW2)
 162                 return -ENODEV;
 163         if (sr & RV3029_STATUS_VLOW1) {
 164                 /* We clear the bits and retry once just in case
 165                  * we had a brown out in early startup.
 166                  */
 167                 ret = regmap_update_bits(rv3029->regmap, RV3029_STATUS,
 168                                          RV3029_STATUS_VLOW1, 0);
 169                 if (ret < 0)
 170                         return ret;
 171                 usleep_range(1000, 10000);
 172                 ret = regmap_read(rv3029->regmap, RV3029_STATUS, &sr);
 173                 if (ret < 0)
 174                         return ret;
 175                 if (sr & RV3029_STATUS_VLOW1) {
 176                         dev_err(rv3029->dev,
 177                                 "Supply voltage is too low to safely access the EEPROM.\n");
 178                         return -ENODEV;
 179                 }
 180         }
 181
 182         /* Disable eeprom refresh. */
 183         ret = regmap_update_bits(rv3029->regmap, RV3029_ONOFF_CTRL,
 184                                  RV3029_ONOFF_CTRL_EERE, 0);
 185         if (ret < 0)
 186                 return ret;
 187
 188         /* Wait for any previous eeprom accesses to finish. */
 189         ret = rv3029_eeprom_busywait(rv3029);
 190         if (ret < 0)
 191                 rv3029_eeprom_exit(rv3029);
 192
 193         return ret;
 194 }
 195
 196 static int rv3029_eeprom_read(struct rv3029_data *rv3029, u8 reg,
 197                               u8 buf[], size_t len)
 198 {
 199         int ret, err;
 200
 201         err = rv3029_eeprom_enter(rv3029);
 202         if (err < 0)
 203                 return err;
 204
 205         ret = regmap_bulk_read(rv3029->regmap, reg, buf, len);
 206
 207         err = rv3029_eeprom_exit(rv3029);
 208         if (err < 0)
 209                 return err;
 210
 211         return ret;
 212 }
 213
 214 static int rv3029_eeprom_write(struct rv3029_data *rv3029, u8 reg,
 215                                u8 const buf[], size_t len)
 216 {
 217         unsigned int tmp;
 218         int ret, err;
 219         size_t i;
 220
 221         err = rv3029_eeprom_enter(rv3029);
 222         if (err < 0)
 223                 return err;
 224
 225         for (i = 0; i < len; i++, reg++) {
 226                 ret = regmap_read(rv3029->regmap, reg, &tmp);
 227                 if (ret < 0)
 228                         break;
 229                 if (tmp != buf[i]) {
 230                         tmp = buf[i];
 231                         ret = regmap_write(rv3029->regmap, reg, tmp);
 232                         if (ret < 0)
 233                                 break;
 234                 }
 235                 ret = rv3029_eeprom_busywait(rv3029);
 236                 if (ret < 0)
 237                         break;
 238         }
 239
 240         err = rv3029_eeprom_exit(rv3029);
 241         if (err < 0)
 242                 return err;
 243
 244         return ret;
 245 }
 246
 247 static int rv3029_eeprom_update_bits(struct rv3029_data *rv3029,
 248                                      u8 reg, u8 mask, u8 set)
 249 {
 250         u8 buf;
 251         int ret;
 252
 253         ret = rv3029_eeprom_read(rv3029, reg, &buf, 1);
 254         if (ret < 0)
 255                 return ret;
 256         buf &= ~mask;
 257         buf |= set & mask;
 258         ret = rv3029_eeprom_write(rv3029, reg, &buf, 1);
 259         if (ret < 0)
 260                 return ret;
 261
 262         return 0;
 263 }
 264
 265 static irqreturn_t rv3029_handle_irq(int irq, void *dev_id)
 266 {
 267         struct device *dev = dev_id;
 268         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 269         unsigned int flags, controls;
 270         unsigned long events = 0;
 271         int ret;
 272
 273         rtc_lock(rv3029->rtc);
 274
 275         ret = regmap_read(rv3029->regmap, RV3029_IRQ_CTRL, &controls);
 276         if (ret) {
 277                 dev_warn(dev, "Read IRQ Control Register error %d\n", ret);
 278                 rtc_unlock(rv3029->rtc);
 279                 return IRQ_NONE;
 280         }
 281
 282         ret = regmap_read(rv3029->regmap, RV3029_IRQ_FLAGS, &flags);
 283         if (ret) {
 284                 dev_warn(dev, "Read IRQ Flags Register error %d\n", ret);
 285                 rtc_unlock(rv3029->rtc);
 286                 return IRQ_NONE;
 287         }
 288
 289         if (flags & RV3029_IRQ_FLAGS_AF) {
 290                 flags &= ~RV3029_IRQ_FLAGS_AF;
 291                 controls &= ~RV3029_IRQ_CTRL_AIE;
 292                 events |= RTC_AF;
 293         }
 294
 295         if (events) {
 296                 rtc_update_irq(rv3029->rtc, 1, events);
 297                 regmap_write(rv3029->regmap, RV3029_IRQ_FLAGS, flags);
 298                 regmap_write(rv3029->regmap, RV3029_IRQ_CTRL, controls);
 299         }
 300         rtc_unlock(rv3029->rtc);
 301
 302         return IRQ_HANDLED;
 303 }
 304
 305 static int rv3029_read_time(struct device *dev, struct rtc_time *tm)
 306 {
 307         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 308         unsigned int sr;
 309         int ret;
 310         u8 regs[RV3029_WATCH_SECTION_LEN] = { 0, };
 311
 312         ret = regmap_read(rv3029->regmap, RV3029_STATUS, &sr);
 313         if (ret < 0)
 314                 return ret;
 315
 316         if (sr & (RV3029_STATUS_VLOW2 | RV3029_STATUS_PON))
 317                 return -EINVAL;
 318
 319         ret = regmap_bulk_read(rv3029->regmap, RV3029_W_SEC, regs,
 320                                RV3029_WATCH_SECTION_LEN);
 321         if (ret < 0)
 322                 return ret;
 323
 324         tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
 325         tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
 326
 327         /* HR field has a more complex interpretation */
 328         {
 329                 const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
 330
 331                 if (_hr & RV3029_REG_HR_12_24) {
 332                         /* 12h format */
 333                         tm->tm_hour = bcd2bin(_hr & 0x1f);
 334                         if (_hr & RV3029_REG_HR_PM)     /* PM flag set */
 335                                 tm->tm_hour += 12;
 336                 } else /* 24h format */
 337                         tm->tm_hour = bcd2bin(_hr & 0x3f);
 338         }
 339
 340         tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
 341         tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
 342         tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 100;
 343         tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
 344
 345         return 0;
 346 }
 347
 348 static int rv3029_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 349 {
 350         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 351         struct rtc_time *const tm = &alarm->time;
 352         unsigned int controls, flags;
 353         int ret;
 354         u8 regs[8];
 355
 356         ret = regmap_bulk_read(rv3029->regmap, RV3029_A_SC, regs,
 357                                RV3029_ALARM_SECTION_LEN);
 358         if (ret < 0)
 359                 return ret;
 360
 361         ret = regmap_read(rv3029->regmap, RV3029_IRQ_CTRL, &controls);
 362         if (ret)
 363                 return ret;
 364
 365         ret = regmap_read(rv3029->regmap, RV3029_IRQ_FLAGS, &flags);
 366         if (ret < 0)
 367                 return ret;
 368
 369         tm->tm_sec = bcd2bin(regs[RV3029_A_SC - RV3029_A_SC] & 0x7f);
 370         tm->tm_min = bcd2bin(regs[RV3029_A_MN - RV3029_A_SC] & 0x7f);
 371         tm->tm_hour = bcd2bin(regs[RV3029_A_HR - RV3029_A_SC] & 0x3f);
 372         tm->tm_mday = bcd2bin(regs[RV3029_A_DT - RV3029_A_SC] & 0x3f);
 373         tm->tm_mon = bcd2bin(regs[RV3029_A_MO - RV3029_A_SC] & 0x1f) - 1;
 374         tm->tm_year = bcd2bin(regs[RV3029_A_YR - RV3029_A_SC] & 0x7f) + 100;
 375         tm->tm_wday = bcd2bin(regs[RV3029_A_DW - RV3029_A_SC] & 0x07) - 1;
 376
 377         alarm->enabled = !!(controls & RV3029_IRQ_CTRL_AIE);
 378         alarm->pending = (flags & RV3029_IRQ_FLAGS_AF) && alarm->enabled;
 379
 380         return 0;
 381 }
 382
 383 static int rv3029_alarm_irq_enable(struct device *dev, unsigned int enable)
 384 {
 385         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 386
 387         return regmap_update_bits(rv3029->regmap, RV3029_IRQ_CTRL,
 388                                   RV3029_IRQ_CTRL_AIE,
 389                                   enable ? RV3029_IRQ_CTRL_AIE : 0);
 390 }
 391
 392 static int rv3029_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 393 {
 394         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 395         struct rtc_time *const tm = &alarm->time;
 396         int ret;
 397         u8 regs[8];
 398
 399         /* Activate all the alarms with AE_x bit */
 400         regs[RV3029_A_SC - RV3029_A_SC] = bin2bcd(tm->tm_sec) | RV3029_A_AE_X;
 401         regs[RV3029_A_MN - RV3029_A_SC] = bin2bcd(tm->tm_min) | RV3029_A_AE_X;
 402         regs[RV3029_A_HR - RV3029_A_SC] = (bin2bcd(tm->tm_hour) & 0x3f)
 403                 | RV3029_A_AE_X;
 404         regs[RV3029_A_DT - RV3029_A_SC] = (bin2bcd(tm->tm_mday) & 0x3f)
 405                 | RV3029_A_AE_X;
 406         regs[RV3029_A_MO - RV3029_A_SC] = (bin2bcd(tm->tm_mon + 1) & 0x1f)
 407                 | RV3029_A_AE_X;
 408         regs[RV3029_A_DW - RV3029_A_SC] = (bin2bcd(tm->tm_wday + 1) & 0x7)
 409                 | RV3029_A_AE_X;
 410         regs[RV3029_A_YR - RV3029_A_SC] = (bin2bcd(tm->tm_year - 100))
 411                 | RV3029_A_AE_X;
 412
 413         /* Write the alarm */
 414         ret = regmap_bulk_write(rv3029->regmap, RV3029_A_SC, regs,
 415                                 RV3029_ALARM_SECTION_LEN);
 416         if (ret < 0)
 417                 return ret;
 418
 419         return rv3029_alarm_irq_enable(dev, alarm->enabled);
 420 }
 421
 422 static int rv3029_set_time(struct device *dev, struct rtc_time *tm)
 423 {
 424         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 425         u8 regs[8];
 426         int ret;
 427
 428         regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
 429         regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
 430         regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
 431         regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
 432         regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
 433         regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
 434         regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 100);
 435
 436         ret = regmap_bulk_write(rv3029->regmap, RV3029_W_SEC, regs,
 437                                 RV3029_WATCH_SECTION_LEN);
 438         if (ret < 0)
 439                 return ret;
 440
 441         /* clear PON and VLOW2 bits */
 442         return regmap_update_bits(rv3029->regmap, RV3029_STATUS,
 443                                   RV3029_STATUS_PON | RV3029_STATUS_VLOW2, 0);
 444 }
 445
 446 static int rv3029_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 447 {
 448         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 449         unsigned long vl = 0;
 450         int sr, ret = 0;
 451
 452         switch (cmd) {
 453         case RTC_VL_READ:
 454                 ret = regmap_read(rv3029->regmap, RV3029_STATUS, &sr);
 455                 if (ret < 0)
 456                         return ret;
 457
 458                 if (sr & RV3029_STATUS_VLOW1)
 459                         vl = RTC_VL_ACCURACY_LOW;
 460
 461                 if (sr & (RV3029_STATUS_VLOW2 | RV3029_STATUS_PON))
 462                         vl |= RTC_VL_DATA_INVALID;
 463
 464                 return put_user(vl, (unsigned int __user *)arg);
 465
 466         case RTC_VL_CLR:
 467                 return regmap_update_bits(rv3029->regmap, RV3029_STATUS,
 468                                           RV3029_STATUS_VLOW1, 0);
 469
 470         default:
 471                 return -ENOIOCTLCMD;
 472         }
 473 }
 474
 475 static int rv3029_nvram_write(void *priv, unsigned int offset, void *val,
 476                               size_t bytes)
 477 {
 478         return regmap_bulk_write(priv, RV3029_RAM_PAGE + offset, val, bytes);
 479 }
 480
 481 static int rv3029_nvram_read(void *priv, unsigned int offset, void *val,
 482                              size_t bytes)
 483 {
 484         return regmap_bulk_read(priv, RV3029_RAM_PAGE + offset, val, bytes);
 485 }
 486
 487 static const struct rv3029_trickle_tab_elem {
 488         u32 r;          /* resistance in ohms */
 489         u8 conf;        /* trickle config bits */
 490 } rv3029_trickle_tab[] = {
 491         {
 492                 .r      = 1076,
 493                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 494                           RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
 495         }, {
 496                 .r      = 1091,
 497                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 498                           RV3029_TRICKLE_20K,
 499         }, {
 500                 .r      = 1137,
 501                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 502                           RV3029_TRICKLE_80K,
 503         }, {
 504                 .r      = 1154,
 505                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,
 506         }, {
 507                 .r      = 1371,
 508                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |
 509                           RV3029_TRICKLE_80K,
 510         }, {
 511                 .r      = 1395,
 512                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,
 513         }, {
 514                 .r      = 1472,
 515                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,
 516         }, {
 517                 .r      = 1500,
 518                 .conf   = RV3029_TRICKLE_1K,
 519         }, {
 520                 .r      = 3810,
 521                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |
 522                           RV3029_TRICKLE_80K,
 523         }, {
 524                 .r      = 4000,
 525                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,
 526         }, {
 527                 .r      = 4706,
 528                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,
 529         }, {
 530                 .r      = 5000,
 531                 .conf   = RV3029_TRICKLE_5K,
 532         }, {
 533                 .r      = 16000,
 534                 .conf   = RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
 535         }, {
 536                 .r      = 20000,
 537                 .conf   = RV3029_TRICKLE_20K,
 538         }, {
 539                 .r      = 80000,
 540                 .conf   = RV3029_TRICKLE_80K,
 541         },
 542 };
 543
 544 static void rv3029_trickle_config(struct device *dev)
 545 {
 546         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 547         struct device_node *of_node = dev->of_node;
 548         const struct rv3029_trickle_tab_elem *elem;
 549         int i, err;
 550         u32 ohms;
 551         u8 trickle_set_bits;
 552
 553         if (!of_node)
 554                 return;
 555
 556         /* Configure the trickle charger. */
 557         err = of_property_read_u32(of_node, "trickle-resistor-ohms", &ohms);
 558         if (err) {
 559                 /* Disable trickle charger. */
 560                 trickle_set_bits = 0;
 561         } else {
 562                 /* Enable trickle charger. */
 563                 for (i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++) {
 564                         elem = &rv3029_trickle_tab[i];
 565                         if (elem->r >= ohms)
 566                                 break;
 567                 }
 568                 trickle_set_bits = elem->conf;
 569                 dev_info(dev,
 570                          "Trickle charger enabled at %d ohms resistance.\n",
 571                          elem->r);
 572         }
 573         err = rv3029_eeprom_update_bits(rv3029, RV3029_CONTROL_E2P_EECTRL,
 574                                         RV3029_TRICKLE_MASK,
 575                                         trickle_set_bits);
 576         if (err < 0)
 577                 dev_err(dev, "Failed to update trickle charger config\n");
 578 }
 579
 580 #ifdef CONFIG_RTC_DRV_RV3029_HWMON
 581
 582 static int rv3029_read_temp(struct rv3029_data *rv3029, int *temp_mC)
 583 {
 584         unsigned int temp;
 585         int ret;
 586
 587         ret = regmap_read(rv3029->regmap, RV3029_TEMP_PAGE, &temp);
 588         if (ret < 0)
 589                 return ret;
 590
 591         *temp_mC = ((int)temp - 60) * 1000;
 592
 593         return 0;
 594 }
 595
 596 static ssize_t rv3029_hwmon_show_temp(struct device *dev,
 597                                       struct device_attribute *attr,
 598                                       char *buf)
 599 {
 600         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 601         int ret, temp_mC;
 602
 603         ret = rv3029_read_temp(rv3029, &temp_mC);
 604         if (ret < 0)
 605                 return ret;
 606
 607         return sprintf(buf, "%d\n", temp_mC);
 608 }
 609
 610 static ssize_t rv3029_hwmon_set_update_interval(struct device *dev,
 611                                                 struct device_attribute *attr,
 612                                                 const char *buf,
 613                                                 size_t count)
 614 {
 615         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 616         unsigned int th_set_bits = 0;
 617         unsigned long interval_ms;
 618         int ret;
 619
 620         ret = kstrtoul(buf, 10, &interval_ms);
 621         if (ret < 0)
 622                 return ret;
 623
 624         if (interval_ms != 0) {
 625                 th_set_bits |= RV3029_EECTRL_THE;
 626                 if (interval_ms >= 16000)
 627                         th_set_bits |= RV3029_EECTRL_THP;
 628         }
 629         ret = rv3029_eeprom_update_bits(rv3029, RV3029_CONTROL_E2P_EECTRL,
 630                                         RV3029_EECTRL_THE | RV3029_EECTRL_THP,
 631                                         th_set_bits);
 632         if (ret < 0)
 633                 return ret;
 634
 635         return count;
 636 }
 637
 638 static ssize_t rv3029_hwmon_show_update_interval(struct device *dev,
 639                                                  struct device_attribute *attr,
 640                                                  char *buf)
 641 {
 642         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 643         int ret, interval_ms;
 644         u8 eectrl;
 645
 646         ret = rv3029_eeprom_read(rv3029, RV3029_CONTROL_E2P_EECTRL,
 647                                  &eectrl, 1);
 648         if (ret < 0)
 649                 return ret;
 650
 651         if (eectrl & RV3029_EECTRL_THE) {
 652                 if (eectrl & RV3029_EECTRL_THP)
 653                         interval_ms = 16000;
 654                 else
 655                         interval_ms = 1000;
 656         } else {
 657                 interval_ms = 0;
 658         }
 659
 660         return sprintf(buf, "%d\n", interval_ms);
 661 }
 662
 663 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, rv3029_hwmon_show_temp,
 664                           NULL, 0);
 665 static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
 666                           rv3029_hwmon_show_update_interval,
 667                           rv3029_hwmon_set_update_interval, 0);
 668
 669 static struct attribute *rv3029_hwmon_attrs[] = {
 670         &sensor_dev_attr_temp1_input.dev_attr.attr,
 671         &sensor_dev_attr_update_interval.dev_attr.attr,
 672         NULL,
 673 };
 674 ATTRIBUTE_GROUPS(rv3029_hwmon);
 675
 676 static void rv3029_hwmon_register(struct device *dev, const char *name)
 677 {
 678         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 679         struct device *hwmon_dev;
 680
 681         hwmon_dev = devm_hwmon_device_register_with_groups(dev, name, rv3029,
 682                                                            rv3029_hwmon_groups);
 683         if (IS_ERR(hwmon_dev)) {
 684                 dev_warn(dev, "unable to register hwmon device %ld\n",
 685                          PTR_ERR(hwmon_dev));
 686         }
 687 }
 688
 689 #else /* CONFIG_RTC_DRV_RV3029_HWMON */
 690
 691 static void rv3029_hwmon_register(struct device *dev, const char *name)
 692 {
 693 }
 694
 695 #endif /* CONFIG_RTC_DRV_RV3029_HWMON */
 696
 697 static const struct rtc_class_ops rv3029_rtc_ops = {
 698         .read_time      = rv3029_read_time,
 699         .set_time       = rv3029_set_time,
 700         .ioctl          = rv3029_ioctl,
 701         .read_alarm     = rv3029_read_alarm,
 702         .set_alarm      = rv3029_set_alarm,
 703         .alarm_irq_enable = rv3029_alarm_irq_enable,
 704 };
 705
 706 static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
 707                         const char *name)
 708 {
 709         struct rv3029_data *rv3029;
 710         struct nvmem_config nvmem_cfg = {
 711                 .name = "rv3029_nvram",
 712                 .word_size = 1,
 713                 .stride = 1,
 714                 .size = RV3029_RAM_SECTION_LEN,
 715                 .type = NVMEM_TYPE_BATTERY_BACKED,
 716                 .reg_read = rv3029_nvram_read,
 717                 .reg_write = rv3029_nvram_write,
 718         };
 719         int rc = 0;
 720
 721         rv3029 = devm_kzalloc(dev, sizeof(*rv3029), GFP_KERNEL);
 722         if (!rv3029)
 723                 return -ENOMEM;
 724
 725         rv3029->regmap = regmap;
 726         rv3029->irq = irq;
 727         rv3029->dev = dev;
 728         dev_set_drvdata(dev, rv3029);
 729
 730         rv3029_trickle_config(dev);
 731         rv3029_hwmon_register(dev, name);
 732
 733         rv3029->rtc = devm_rtc_allocate_device(dev);
 734         if (IS_ERR(rv3029->rtc))
 735                 return PTR_ERR(rv3029->rtc);
 736
 737         if (rv3029->irq > 0) {
 738                 unsigned long irqflags = IRQF_TRIGGER_LOW;
 739
 740                 if (dev_fwnode(dev))
 741                         irqflags = 0;
 742
 743                 rc = devm_request_threaded_irq(dev, rv3029->irq,
 744                                                NULL, rv3029_handle_irq,
 745                                                irqflags | IRQF_ONESHOT,
 746                                                "rv3029", dev);
 747                 if (rc) {
 748                         dev_warn(dev, "unable to request IRQ, alarms disabled\n");
 749                         rv3029->irq = 0;
 750                 }
 751         }
 752         if (!rv3029->irq)
 753                 clear_bit(RTC_FEATURE_ALARM, rv3029->rtc->features);
 754
 755         rv3029->rtc->ops = &rv3029_rtc_ops;
 756         rv3029->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 757         rv3029->rtc->range_max = RTC_TIMESTAMP_END_2079;
 758
 759         rc = devm_rtc_register_device(rv3029->rtc);
 760         if (rc)
 761                 return rc;
 762
 763         nvmem_cfg.priv = rv3029->regmap;
 764         devm_rtc_nvmem_register(rv3029->rtc, &nvmem_cfg);
 765
 766         return 0;
 767 }
 768
 769 static const struct regmap_range rv3029_holes_range[] = {
 770         regmap_reg_range(0x05, 0x07),
 771         regmap_reg_range(0x0f, 0x0f),
 772         regmap_reg_range(0x17, 0x17),
 773         regmap_reg_range(0x1a, 0x1f),
 774         regmap_reg_range(0x21, 0x27),
 775         regmap_reg_range(0x34, 0x37),
 776 };
 777
 778 static const struct regmap_access_table rv3029_regs = {
 779         .no_ranges =    rv3029_holes_range,
 780         .n_no_ranges =  ARRAY_SIZE(rv3029_holes_range),
 781 };
 782
 783 static const struct regmap_config config = {
 784         .reg_bits = 8,
 785         .val_bits = 8,
 786         .rd_table = &rv3029_regs,
 787         .wr_table = &rv3029_regs,
 788         .max_register = 0x3f,
 789 };
 790
 791 #if IS_ENABLED(CONFIG_I2C)
 792
 793 static int rv3029_i2c_probe(struct i2c_client *client)
 794 {
 795         struct regmap *regmap;
 796         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
 797                                      I2C_FUNC_SMBUS_BYTE)) {
 798                 dev_err(&client->dev, "Adapter does not support SMBUS_I2C_BLOCK or SMBUS_I2C_BYTE\n");
 799                 return -ENODEV;
 800         }
 801
 802         regmap = devm_regmap_init_i2c(client, &config);
 803         if (IS_ERR(regmap))
 804                 return PTR_ERR(regmap);
 805
 806         return rv3029_probe(&client->dev, regmap, client->irq, client->name);
 807 }
 808
 809 static const struct i2c_device_id rv3029_id[] = {
 810         { "rv3029", 0 },
 811         { "rv3029c2", 0 },
 812         { }
 813 };
 814 MODULE_DEVICE_TABLE(i2c, rv3029_id);
 815
 816 static const __maybe_unused struct of_device_id rv3029_of_match[] = {
 817         { .compatible = "microcrystal,rv3029" },
 818         { }
 819 };
 820 MODULE_DEVICE_TABLE(of, rv3029_of_match);
 821
 822 static struct i2c_driver rv3029_driver = {
 823         .driver = {
 824                 .name = "rv3029",
 825                 .of_match_table = of_match_ptr(rv3029_of_match),
 826         },
 827         .probe          = rv3029_i2c_probe,
 828         .id_table       = rv3029_id,
 829 };
 830
 831 static int __init rv3029_register_driver(void)
 832 {
 833         return i2c_add_driver(&rv3029_driver);
 834 }
 835
 836 static void rv3029_unregister_driver(void)
 837 {
 838         i2c_del_driver(&rv3029_driver);
 839 }
 840
 841 #else
 842
 843 static int __init rv3029_register_driver(void)
 844 {
 845         return 0;
 846 }
 847
 848 static void rv3029_unregister_driver(void)
 849 {
 850 }
 851
 852 #endif
 853
 854 #if IS_ENABLED(CONFIG_SPI_MASTER)
 855
 856 static int rv3049_probe(struct spi_device *spi)
 857 {
 858         struct regmap *regmap;
 859
 860         regmap = devm_regmap_init_spi(spi, &config);
 861         if (IS_ERR(regmap))
 862                 return PTR_ERR(regmap);
 863
 864         return rv3029_probe(&spi->dev, regmap, spi->irq, "rv3049");
 865 }
 866
 867 static struct spi_driver rv3049_driver = {
 868         .driver = {
 869                 .name    = "rv3049",
 870         },
 871         .probe   = rv3049_probe,
 872 };
 873
 874 static int __init rv3049_register_driver(void)
 875 {
 876         return spi_register_driver(&rv3049_driver);
 877 }
 878
 879 static void __exit rv3049_unregister_driver(void)
 880 {
 881         spi_unregister_driver(&rv3049_driver);
 882 }
 883
 884 #else
 885
 886 static int __init rv3049_register_driver(void)
 887 {
 888         return 0;
 889 }
 890
 891 static void __exit rv3049_unregister_driver(void)
 892 {
 893 }
 894
 895 #endif
 896
 897 static int __init rv30x9_init(void)
 898 {
 899         int ret;
 900
 901         ret = rv3029_register_driver();
 902         if (ret)
 903                 return ret;
 904
 905         ret = rv3049_register_driver();
 906         if (ret)
 907                 rv3029_unregister_driver();
 908
 909         return ret;
 910 }
 911 module_init(rv30x9_init)
 912
 913 static void __exit rv30x9_exit(void)
 914 {
 915         rv3049_unregister_driver();
 916         rv3029_unregister_driver();
 917 }
 918 module_exit(rv30x9_exit)
 919
 920 MODULE_AUTHOR("Gregory Hermant <gregory.hermant@calao-systems.com>");
 921 MODULE_AUTHOR("Michael Buesch <m@bues.ch>");
 922 MODULE_DESCRIPTION("Micro Crystal RV3029/RV3049 RTC driver");
 923 MODULE_LICENSE("GPL");
 924 MODULE_ALIAS("spi:rv3049");