drivers/rtc/rtc-rv3029c2.c

   1 /*
   2  * Micro Crystal RV-3029 / RV-3049 rtc class driver
   3  *
   4  * Author: Gregory Hermant <gregory.hermant@calao-systems.com>
   5  *         Michael Buesch <m@bues.ch>
   6  *
   7  * based on previously existing rtc class drivers
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/i2c.h>
  17 #include <linux/spi/spi.h>
  18 #include <linux/bcd.h>
  19 #include <linux/rtc.h>
  20 #include <linux/delay.h>
  21 #include <linux/of.h>
  22 #include <linux/hwmon.h>
  23 #include <linux/hwmon-sysfs.h>
  24 #include <linux/regmap.h>
  25
  26 /* Register map */
  27 /* control section */
  28 #define RV3029_ONOFF_CTRL               0x00
  29 #define RV3029_ONOFF_CTRL_WE            BIT(0)
  30 #define RV3029_ONOFF_CTRL_TE            BIT(1)
  31 #define RV3029_ONOFF_CTRL_TAR           BIT(2)
  32 #define RV3029_ONOFF_CTRL_EERE          BIT(3)
  33 #define RV3029_ONOFF_CTRL_SRON          BIT(4)
  34 #define RV3029_ONOFF_CTRL_TD0           BIT(5)
  35 #define RV3029_ONOFF_CTRL_TD1           BIT(6)
  36 #define RV3029_ONOFF_CTRL_CLKINT        BIT(7)
  37 #define RV3029_IRQ_CTRL                 0x01
  38 #define RV3029_IRQ_CTRL_AIE             BIT(0)
  39 #define RV3029_IRQ_CTRL_TIE             BIT(1)
  40 #define RV3029_IRQ_CTRL_V1IE            BIT(2)
  41 #define RV3029_IRQ_CTRL_V2IE            BIT(3)
  42 #define RV3029_IRQ_CTRL_SRIE            BIT(4)
  43 #define RV3029_IRQ_FLAGS                0x02
  44 #define RV3029_IRQ_FLAGS_AF             BIT(0)
  45 #define RV3029_IRQ_FLAGS_TF             BIT(1)
  46 #define RV3029_IRQ_FLAGS_V1IF           BIT(2)
  47 #define RV3029_IRQ_FLAGS_V2IF           BIT(3)
  48 #define RV3029_IRQ_FLAGS_SRF            BIT(4)
  49 #define RV3029_STATUS                   0x03
  50 #define RV3029_STATUS_VLOW1             BIT(2)
  51 #define RV3029_STATUS_VLOW2             BIT(3)
  52 #define RV3029_STATUS_SR                BIT(4)
  53 #define RV3029_STATUS_PON               BIT(5)
  54 #define RV3029_STATUS_EEBUSY            BIT(7)
  55 #define RV3029_RST_CTRL                 0x04
  56 #define RV3029_RST_CTRL_SYSR            BIT(4)
  57 #define RV3029_CONTROL_SECTION_LEN      0x05
  58
  59 /* watch section */
  60 #define RV3029_W_SEC                    0x08
  61 #define RV3029_W_MINUTES                0x09
  62 #define RV3029_W_HOURS                  0x0A
  63 #define RV3029_REG_HR_12_24             BIT(6) /* 24h/12h mode */
  64 #define RV3029_REG_HR_PM                BIT(5) /* PM/AM bit in 12h mode */
  65 #define RV3029_W_DATE                   0x0B
  66 #define RV3029_W_DAYS                   0x0C
  67 #define RV3029_W_MONTHS                 0x0D
  68 #define RV3029_W_YEARS                  0x0E
  69 #define RV3029_WATCH_SECTION_LEN        0x07
  70
  71 /* alarm section */
  72 #define RV3029_A_SC                     0x10
  73 #define RV3029_A_MN                     0x11
  74 #define RV3029_A_HR                     0x12
  75 #define RV3029_A_DT                     0x13
  76 #define RV3029_A_DW                     0x14
  77 #define RV3029_A_MO                     0x15
  78 #define RV3029_A_YR                     0x16
  79 #define RV3029_A_AE_X                   BIT(7)
  80 #define RV3029_ALARM_SECTION_LEN        0x07
  81
  82 /* timer section */
  83 #define RV3029_TIMER_LOW                0x18
  84 #define RV3029_TIMER_HIGH               0x19
  85
  86 /* temperature section */
  87 #define RV3029_TEMP_PAGE                0x20
  88
  89 /* eeprom data section */
  90 #define RV3029_E2P_EEDATA1              0x28
  91 #define RV3029_E2P_EEDATA2              0x29
  92 #define RV3029_E2PDATA_SECTION_LEN      0x02
  93
  94 /* eeprom control section */
  95 #define RV3029_CONTROL_E2P_EECTRL       0x30
  96 #define RV3029_EECTRL_THP               BIT(0) /* temp scan interval */
  97 #define RV3029_EECTRL_THE               BIT(1) /* thermometer enable */
  98 #define RV3029_EECTRL_FD0               BIT(2) /* CLKOUT */
  99 #define RV3029_EECTRL_FD1               BIT(3) /* CLKOUT */
 100 #define RV3029_TRICKLE_1K               BIT(4) /* 1.5K resistance */
 101 #define RV3029_TRICKLE_5K               BIT(5) /* 5K   resistance */
 102 #define RV3029_TRICKLE_20K              BIT(6) /* 20K  resistance */
 103 #define RV3029_TRICKLE_80K              BIT(7) /* 80K  resistance */
 104 #define RV3029_TRICKLE_MASK             (RV3029_TRICKLE_1K |\
 105                                          RV3029_TRICKLE_5K |\
 106                                          RV3029_TRICKLE_20K |\
 107                                          RV3029_TRICKLE_80K)
 108 #define RV3029_TRICKLE_SHIFT            4
 109 #define RV3029_CONTROL_E2P_XOFFS        0x31 /* XTAL offset */
 110 #define RV3029_CONTROL_E2P_XOFFS_SIGN   BIT(7) /* Sign: 1->pos, 0->neg */
 111 #define RV3029_CONTROL_E2P_QCOEF        0x32 /* XTAL temp drift coef */
 112 #define RV3029_CONTROL_E2P_TURNOVER     0x33 /* XTAL turnover temp (in *C) */
 113 #define RV3029_CONTROL_E2P_TOV_MASK     0x3F /* XTAL turnover temp mask */
 114
 115 /* user ram section */
 116 #define RV3029_USR1_RAM_PAGE            0x38
 117 #define RV3029_USR1_SECTION_LEN         0x04
 118 #define RV3029_USR2_RAM_PAGE            0x3C
 119 #define RV3029_USR2_SECTION_LEN         0x04
 120
 121 struct rv3029_data {
 122         struct device           *dev;
 123         struct rtc_device       *rtc;
 124         struct regmap           *regmap;
 125         int irq;
 126 };
 127
 128 static int rv3029_read_regs(struct device *dev, u8 reg, u8 *buf,
 129                             unsigned int len)
 130 {
 131         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 132
 133         if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
 134             (reg + len > RV3029_USR1_RAM_PAGE + 8))
 135                 return -EINVAL;
 136
 137         return regmap_bulk_read(rv3029->regmap, reg, buf, len);
 138 }
 139
 140 static int rv3029_write_regs(struct device *dev, u8 reg, u8 const buf[],
 141                              unsigned int len)
 142 {
 143         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 144
 145         if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
 146             (reg + len > RV3029_USR1_RAM_PAGE + 8))
 147                 return -EINVAL;
 148
 149         return regmap_bulk_write(rv3029->regmap, reg, buf, len);
 150 }
 151
 152 static int rv3029_update_bits(struct device *dev, u8 reg, u8 mask, u8 set)
 153 {
 154         u8 buf;
 155         int ret;
 156
 157         ret = rv3029_read_regs(dev, reg, &buf, 1);
 158         if (ret < 0)
 159                 return ret;
 160         buf &= ~mask;
 161         buf |= set & mask;
 162         ret = rv3029_write_regs(dev, reg, &buf, 1);
 163         if (ret < 0)
 164                 return ret;
 165
 166         return 0;
 167 }
 168
 169 static int rv3029_get_sr(struct device *dev, u8 *buf)
 170 {
 171         int ret = rv3029_read_regs(dev, RV3029_STATUS, buf, 1);
 172
 173         if (ret < 0)
 174                 return -EIO;
 175         dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
 176         return 0;
 177 }
 178
 179 static int rv3029_set_sr(struct device *dev, u8 val)
 180 {
 181         u8 buf[1];
 182         int sr;
 183
 184         buf[0] = val;
 185         sr = rv3029_write_regs(dev, RV3029_STATUS, buf, 1);
 186         dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
 187         if (sr < 0)
 188                 return -EIO;
 189         return 0;
 190 }
 191
 192 static int rv3029_eeprom_busywait(struct device *dev)
 193 {
 194         int i, ret;
 195         u8 sr;
 196
 197         for (i = 100; i > 0; i--) {
 198                 ret = rv3029_get_sr(dev, &sr);
 199                 if (ret < 0)
 200                         break;
 201                 if (!(sr & RV3029_STATUS_EEBUSY))
 202                         break;
 203                 usleep_range(1000, 10000);
 204         }
 205         if (i <= 0) {
 206                 dev_err(dev, "EEPROM busy wait timeout.\n");
 207                 return -ETIMEDOUT;
 208         }
 209
 210         return ret;
 211 }
 212
 213 static int rv3029_eeprom_exit(struct device *dev)
 214 {
 215         /* Re-enable eeprom refresh */
 216         return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
 217                                   RV3029_ONOFF_CTRL_EERE,
 218                                   RV3029_ONOFF_CTRL_EERE);
 219 }
 220
 221 static int rv3029_eeprom_enter(struct device *dev)
 222 {
 223         int ret;
 224         u8 sr;
 225
 226         /* Check whether we are in the allowed voltage range. */
 227         ret = rv3029_get_sr(dev, &sr);
 228         if (ret < 0)
 229                 return ret;
 230         if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
 231                 /* We clear the bits and retry once just in case
 232                  * we had a brown out in early startup.
 233                  */
 234                 sr &= ~RV3029_STATUS_VLOW1;
 235                 sr &= ~RV3029_STATUS_VLOW2;
 236                 ret = rv3029_set_sr(dev, sr);
 237                 if (ret < 0)
 238                         return ret;
 239                 usleep_range(1000, 10000);
 240                 ret = rv3029_get_sr(dev, &sr);
 241                 if (ret < 0)
 242                         return ret;
 243                 if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
 244                         dev_err(dev,
 245                                 "Supply voltage is too low to safely access the EEPROM.\n");
 246                         return -ENODEV;
 247                 }
 248         }
 249
 250         /* Disable eeprom refresh. */
 251         ret = rv3029_update_bits(dev, RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE,
 252                                  0);
 253         if (ret < 0)
 254                 return ret;
 255
 256         /* Wait for any previous eeprom accesses to finish. */
 257         ret = rv3029_eeprom_busywait(dev);
 258         if (ret < 0)
 259                 rv3029_eeprom_exit(dev);
 260
 261         return ret;
 262 }
 263
 264 static int rv3029_eeprom_read(struct device *dev, u8 reg,
 265                               u8 buf[], size_t len)
 266 {
 267         int ret, err;
 268
 269         err = rv3029_eeprom_enter(dev);
 270         if (err < 0)
 271                 return err;
 272
 273         ret = rv3029_read_regs(dev, reg, buf, len);
 274
 275         err = rv3029_eeprom_exit(dev);
 276         if (err < 0)
 277                 return err;
 278
 279         return ret;
 280 }
 281
 282 static int rv3029_eeprom_write(struct device *dev, u8 reg,
 283                                u8 const buf[], size_t len)
 284 {
 285         int ret, err;
 286         size_t i;
 287         u8 tmp;
 288
 289         err = rv3029_eeprom_enter(dev);
 290         if (err < 0)
 291                 return err;
 292
 293         for (i = 0; i < len; i++, reg++) {
 294                 ret = rv3029_read_regs(dev, reg, &tmp, 1);
 295                 if (ret < 0)
 296                         break;
 297                 if (tmp != buf[i]) {
 298                         ret = rv3029_write_regs(dev, reg, &buf[i], 1);
 299                         if (ret < 0)
 300                                 break;
 301                 }
 302                 ret = rv3029_eeprom_busywait(dev);
 303                 if (ret < 0)
 304                         break;
 305         }
 306
 307         err = rv3029_eeprom_exit(dev);
 308         if (err < 0)
 309                 return err;
 310
 311         return ret;
 312 }
 313
 314 static int rv3029_eeprom_update_bits(struct device *dev,
 315                                      u8 reg, u8 mask, u8 set)
 316 {
 317         u8 buf;
 318         int ret;
 319
 320         ret = rv3029_eeprom_read(dev, reg, &buf, 1);
 321         if (ret < 0)
 322                 return ret;
 323         buf &= ~mask;
 324         buf |= set & mask;
 325         ret = rv3029_eeprom_write(dev, reg, &buf, 1);
 326         if (ret < 0)
 327                 return ret;
 328
 329         return 0;
 330 }
 331
 332 static int rv3029_read_time(struct device *dev, struct rtc_time *tm)
 333 {
 334         u8 buf[1];
 335         int ret;
 336         u8 regs[RV3029_WATCH_SECTION_LEN] = { 0, };
 337
 338         ret = rv3029_get_sr(dev, buf);
 339         if (ret < 0) {
 340                 dev_err(dev, "%s: reading SR failed\n", __func__);
 341                 return -EIO;
 342         }
 343
 344         ret = rv3029_read_regs(dev, RV3029_W_SEC, regs,
 345                                RV3029_WATCH_SECTION_LEN);
 346         if (ret < 0) {
 347                 dev_err(dev, "%s: reading RTC section failed\n", __func__);
 348                 return ret;
 349         }
 350
 351         tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
 352         tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
 353
 354         /* HR field has a more complex interpretation */
 355         {
 356                 const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
 357
 358                 if (_hr & RV3029_REG_HR_12_24) {
 359                         /* 12h format */
 360                         tm->tm_hour = bcd2bin(_hr & 0x1f);
 361                         if (_hr & RV3029_REG_HR_PM)     /* PM flag set */
 362                                 tm->tm_hour += 12;
 363                 } else /* 24h format */
 364                         tm->tm_hour = bcd2bin(_hr & 0x3f);
 365         }
 366
 367         tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
 368         tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
 369         tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 100;
 370         tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
 371
 372         return 0;
 373 }
 374
 375 static int rv3029_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 376 {
 377         struct rtc_time *const tm = &alarm->time;
 378         int ret;
 379         u8 regs[8];
 380
 381         ret = rv3029_get_sr(dev, regs);
 382         if (ret < 0) {
 383                 dev_err(dev, "%s: reading SR failed\n", __func__);
 384                 return -EIO;
 385         }
 386
 387         ret = rv3029_read_regs(dev, RV3029_A_SC, regs,
 388                                RV3029_ALARM_SECTION_LEN);
 389
 390         if (ret < 0) {
 391                 dev_err(dev, "%s: reading alarm section failed\n", __func__);
 392                 return ret;
 393         }
 394
 395         tm->tm_sec = bcd2bin(regs[RV3029_A_SC - RV3029_A_SC] & 0x7f);
 396         tm->tm_min = bcd2bin(regs[RV3029_A_MN - RV3029_A_SC] & 0x7f);
 397         tm->tm_hour = bcd2bin(regs[RV3029_A_HR - RV3029_A_SC] & 0x3f);
 398         tm->tm_mday = bcd2bin(regs[RV3029_A_DT - RV3029_A_SC] & 0x3f);
 399         tm->tm_mon = bcd2bin(regs[RV3029_A_MO - RV3029_A_SC] & 0x1f) - 1;
 400         tm->tm_year = bcd2bin(regs[RV3029_A_YR - RV3029_A_SC] & 0x7f) + 100;
 401         tm->tm_wday = bcd2bin(regs[RV3029_A_DW - RV3029_A_SC] & 0x07) - 1;
 402
 403         return 0;
 404 }
 405
 406 static int rv3029_rtc_alarm_set_irq(struct device *dev, int enable)
 407 {
 408         int ret;
 409
 410         /* enable/disable AIE irq */
 411         ret = rv3029_update_bits(dev, RV3029_IRQ_CTRL, RV3029_IRQ_CTRL_AIE,
 412                                  (enable ? RV3029_IRQ_CTRL_AIE : 0));
 413         if (ret < 0) {
 414                 dev_err(dev, "can't update INT reg\n");
 415                 return ret;
 416         }
 417
 418         return 0;
 419 }
 420
 421 static int rv3029_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 422 {
 423         struct rtc_time *const tm = &alarm->time;
 424         int ret;
 425         u8 regs[8];
 426
 427         /*
 428          * The clock has an 8 bit wide bcd-coded register (they never learn)
 429          * for the year. tm_year is an offset from 1900 and we are interested
 430          * in the 2000-2099 range, so any value less than 100 is invalid.
 431         */
 432         if (tm->tm_year < 100)
 433                 return -EINVAL;
 434
 435         ret = rv3029_get_sr(dev, regs);
 436         if (ret < 0) {
 437                 dev_err(dev, "%s: reading SR failed\n", __func__);
 438                 return -EIO;
 439         }
 440
 441         /* Activate all the alarms with AE_x bit */
 442         regs[RV3029_A_SC - RV3029_A_SC] = bin2bcd(tm->tm_sec) | RV3029_A_AE_X;
 443         regs[RV3029_A_MN - RV3029_A_SC] = bin2bcd(tm->tm_min) | RV3029_A_AE_X;
 444         regs[RV3029_A_HR - RV3029_A_SC] = (bin2bcd(tm->tm_hour) & 0x3f)
 445                 | RV3029_A_AE_X;
 446         regs[RV3029_A_DT - RV3029_A_SC] = (bin2bcd(tm->tm_mday) & 0x3f)
 447                 | RV3029_A_AE_X;
 448         regs[RV3029_A_MO - RV3029_A_SC] = (bin2bcd(tm->tm_mon + 1) & 0x1f)
 449                 | RV3029_A_AE_X;
 450         regs[RV3029_A_DW - RV3029_A_SC] = (bin2bcd(tm->tm_wday + 1) & 0x7)
 451                 | RV3029_A_AE_X;
 452         regs[RV3029_A_YR - RV3029_A_SC] = (bin2bcd(tm->tm_year - 100))
 453                 | RV3029_A_AE_X;
 454
 455         /* Write the alarm */
 456         ret = rv3029_write_regs(dev, RV3029_A_SC, regs,
 457                                 RV3029_ALARM_SECTION_LEN);
 458         if (ret < 0)
 459                 return ret;
 460
 461         if (alarm->enabled) {
 462                 /* clear AF flag */
 463                 ret = rv3029_update_bits(dev, RV3029_IRQ_FLAGS,
 464                                          RV3029_IRQ_FLAGS_AF, 0);
 465                 if (ret < 0) {
 466                         dev_err(dev, "can't clear alarm flag\n");
 467                         return ret;
 468                 }
 469                 /* enable AIE irq */
 470                 ret = rv3029_rtc_alarm_set_irq(dev, 1);
 471                 if (ret)
 472                         return ret;
 473
 474                 dev_dbg(dev, "alarm IRQ armed\n");
 475         } else {
 476                 /* disable AIE irq */
 477                 ret = rv3029_rtc_alarm_set_irq(dev, 0);
 478                 if (ret)
 479                         return ret;
 480
 481                 dev_dbg(dev, "alarm IRQ disabled\n");
 482         }
 483
 484         return 0;
 485 }
 486
 487 static int rv3029_set_time(struct device *dev, struct rtc_time *tm)
 488 {
 489         u8 regs[8];
 490         int ret;
 491
 492         /*
 493          * The clock has an 8 bit wide bcd-coded register (they never learn)
 494          * for the year. tm_year is an offset from 1900 and we are interested
 495          * in the 2000-2099 range, so any value less than 100 is invalid.
 496         */
 497         if (tm->tm_year < 100)
 498                 return -EINVAL;
 499
 500         regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
 501         regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
 502         regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
 503         regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
 504         regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
 505         regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd((tm->tm_wday & 7) + 1);
 506         regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 100);
 507
 508         ret = rv3029_write_regs(dev, RV3029_W_SEC, regs,
 509                                 RV3029_WATCH_SECTION_LEN);
 510         if (ret < 0)
 511                 return ret;
 512
 513         ret = rv3029_get_sr(dev, regs);
 514         if (ret < 0) {
 515                 dev_err(dev, "%s: reading SR failed\n", __func__);
 516                 return ret;
 517         }
 518         /* clear PON bit */
 519         ret = rv3029_set_sr(dev, (regs[0] & ~RV3029_STATUS_PON));
 520         if (ret < 0) {
 521                 dev_err(dev, "%s: reading SR failed\n", __func__);
 522                 return ret;
 523         }
 524
 525         return 0;
 526 }
 527
 528 static const struct rv3029_trickle_tab_elem {
 529         u32 r;          /* resistance in ohms */
 530         u8 conf;        /* trickle config bits */
 531 } rv3029_trickle_tab[] = {
 532         {
 533                 .r      = 1076,
 534                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 535                           RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
 536         }, {
 537                 .r      = 1091,
 538                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 539                           RV3029_TRICKLE_20K,
 540         }, {
 541                 .r      = 1137,
 542                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
 543                           RV3029_TRICKLE_80K,
 544         }, {
 545                 .r      = 1154,
 546                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,
 547         }, {
 548                 .r      = 1371,
 549                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |
 550                           RV3029_TRICKLE_80K,
 551         }, {
 552                 .r      = 1395,
 553                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,
 554         }, {
 555                 .r      = 1472,
 556                 .conf   = RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,
 557         }, {
 558                 .r      = 1500,
 559                 .conf   = RV3029_TRICKLE_1K,
 560         }, {
 561                 .r      = 3810,
 562                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |
 563                           RV3029_TRICKLE_80K,
 564         }, {
 565                 .r      = 4000,
 566                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,
 567         }, {
 568                 .r      = 4706,
 569                 .conf   = RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,
 570         }, {
 571                 .r      = 5000,
 572                 .conf   = RV3029_TRICKLE_5K,
 573         }, {
 574                 .r      = 16000,
 575                 .conf   = RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
 576         }, {
 577                 .r      = 20000,
 578                 .conf   = RV3029_TRICKLE_20K,
 579         }, {
 580                 .r      = 80000,
 581                 .conf   = RV3029_TRICKLE_80K,
 582         },
 583 };
 584
 585 static void rv3029_trickle_config(struct device *dev)
 586 {
 587         struct device_node *of_node = dev->of_node;
 588         const struct rv3029_trickle_tab_elem *elem;
 589         int i, err;
 590         u32 ohms;
 591         u8 trickle_set_bits;
 592
 593         if (!of_node)
 594                 return;
 595
 596         /* Configure the trickle charger. */
 597         err = of_property_read_u32(of_node, "trickle-resistor-ohms", &ohms);
 598         if (err) {
 599                 /* Disable trickle charger. */
 600                 trickle_set_bits = 0;
 601         } else {
 602                 /* Enable trickle charger. */
 603                 for (i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++) {
 604                         elem = &rv3029_trickle_tab[i];
 605                         if (elem->r >= ohms)
 606                                 break;
 607                 }
 608                 trickle_set_bits = elem->conf;
 609                 dev_info(dev,
 610                          "Trickle charger enabled at %d ohms resistance.\n",
 611                          elem->r);
 612         }
 613         err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
 614                                         RV3029_TRICKLE_MASK,
 615                                         trickle_set_bits);
 616         if (err < 0)
 617                 dev_err(dev, "Failed to update trickle charger config\n");
 618 }
 619
 620 #ifdef CONFIG_RTC_DRV_RV3029_HWMON
 621
 622 static int rv3029_read_temp(struct device *dev, int *temp_mC)
 623 {
 624         int ret;
 625         u8 temp;
 626
 627         ret = rv3029_read_regs(dev, RV3029_TEMP_PAGE, &temp, 1);
 628         if (ret < 0)
 629                 return ret;
 630
 631         *temp_mC = ((int)temp - 60) * 1000;
 632
 633         return 0;
 634 }
 635
 636 static ssize_t rv3029_hwmon_show_temp(struct device *dev,
 637                                       struct device_attribute *attr,
 638                                       char *buf)
 639 {
 640         int ret, temp_mC;
 641
 642         ret = rv3029_read_temp(dev, &temp_mC);
 643         if (ret < 0)
 644                 return ret;
 645
 646         return sprintf(buf, "%d\n", temp_mC);
 647 }
 648
 649 static ssize_t rv3029_hwmon_set_update_interval(struct device *dev,
 650                                                 struct device_attribute *attr,
 651                                                 const char *buf,
 652                                                 size_t count)
 653 {
 654         unsigned long interval_ms;
 655         int ret;
 656         u8 th_set_bits = 0;
 657
 658         ret = kstrtoul(buf, 10, &interval_ms);
 659         if (ret < 0)
 660                 return ret;
 661
 662         if (interval_ms != 0) {
 663                 th_set_bits |= RV3029_EECTRL_THE;
 664                 if (interval_ms >= 16000)
 665                         th_set_bits |= RV3029_EECTRL_THP;
 666         }
 667         ret = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
 668                                         RV3029_EECTRL_THE | RV3029_EECTRL_THP,
 669                                         th_set_bits);
 670         if (ret < 0)
 671                 return ret;
 672
 673         return count;
 674 }
 675
 676 static ssize_t rv3029_hwmon_show_update_interval(struct device *dev,
 677                                                  struct device_attribute *attr,
 678                                                  char *buf)
 679 {
 680         int ret, interval_ms;
 681         u8 eectrl;
 682
 683         ret = rv3029_eeprom_read(dev, RV3029_CONTROL_E2P_EECTRL,
 684                                  &eectrl, 1);
 685         if (ret < 0)
 686                 return ret;
 687
 688         if (eectrl & RV3029_EECTRL_THE) {
 689                 if (eectrl & RV3029_EECTRL_THP)
 690                         interval_ms = 16000;
 691                 else
 692                         interval_ms = 1000;
 693         } else {
 694                 interval_ms = 0;
 695         }
 696
 697         return sprintf(buf, "%d\n", interval_ms);
 698 }
 699
 700 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, rv3029_hwmon_show_temp,
 701                           NULL, 0);
 702 static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
 703                           rv3029_hwmon_show_update_interval,
 704                           rv3029_hwmon_set_update_interval, 0);
 705
 706 static struct attribute *rv3029_hwmon_attrs[] = {
 707         &sensor_dev_attr_temp1_input.dev_attr.attr,
 708         &sensor_dev_attr_update_interval.dev_attr.attr,
 709         NULL,
 710 };
 711 ATTRIBUTE_GROUPS(rv3029_hwmon);
 712
 713 static void rv3029_hwmon_register(struct device *dev, const char *name)
 714 {
 715         struct rv3029_data *rv3029 = dev_get_drvdata(dev);
 716         struct device *hwmon_dev;
 717
 718         hwmon_dev = devm_hwmon_device_register_with_groups(dev, name, rv3029,
 719                                                            rv3029_hwmon_groups);
 720         if (IS_ERR(hwmon_dev)) {
 721                 dev_warn(dev, "unable to register hwmon device %ld\n",
 722                          PTR_ERR(hwmon_dev));
 723         }
 724 }
 725
 726 #else /* CONFIG_RTC_DRV_RV3029_HWMON */
 727
 728 static void rv3029_hwmon_register(struct device *dev, const char *name)
 729 {
 730 }
 731
 732 #endif /* CONFIG_RTC_DRV_RV3029_HWMON */
 733
 734 static const struct rtc_class_ops rv3029_rtc_ops = {
 735         .read_time      = rv3029_read_time,
 736         .set_time       = rv3029_set_time,
 737         .read_alarm     = rv3029_read_alarm,
 738         .set_alarm      = rv3029_set_alarm,
 739 };
 740
 741 static struct i2c_device_id rv3029_id[] = {
 742         { "rv3029", 0 },
 743         { "rv3029c2", 0 },
 744         { }
 745 };
 746 MODULE_DEVICE_TABLE(i2c, rv3029_id);
 747
 748 static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
 749                         const char *name)
 750 {
 751         struct rv3029_data *rv3029;
 752         int rc = 0;
 753         u8 buf[1];
 754
 755         rv3029 = devm_kzalloc(dev, sizeof(*rv3029), GFP_KERNEL);
 756         if (!rv3029)
 757                 return -ENOMEM;
 758
 759         rv3029->regmap = regmap;
 760         rv3029->irq = irq;
 761         rv3029->dev = dev;
 762         dev_set_drvdata(dev, rv3029);
 763
 764         rc = rv3029_get_sr(dev, buf);
 765         if (rc < 0) {
 766                 dev_err(dev, "reading status failed\n");
 767                 return rc;
 768         }
 769
 770         rv3029_trickle_config(dev);
 771         rv3029_hwmon_register(dev, name);
 772
 773         rv3029->rtc = devm_rtc_device_register(dev, name, &rv3029_rtc_ops,
 774                                                THIS_MODULE);
 775
 776         return PTR_ERR_OR_ZERO(rv3029->rtc);
 777 }
 778
 779 #if IS_ENABLED(CONFIG_I2C)
 780
 781 static int rv3029_i2c_probe(struct i2c_client *client,
 782                             const struct i2c_device_id *id)
 783 {
 784         struct regmap *regmap;
 785         static const struct regmap_config config = {
 786                 .reg_bits = 8,
 787                 .val_bits = 8,
 788         };
 789
 790         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
 791                                      I2C_FUNC_SMBUS_BYTE)) {
 792                 dev_err(&client->dev, "Adapter does not support SMBUS_I2C_BLOCK or SMBUS_I2C_BYTE\n");
 793                 return -ENODEV;
 794         }
 795
 796         regmap = devm_regmap_init_i2c(client, &config);
 797         if (IS_ERR(regmap)) {
 798                 dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
 799                         __func__, PTR_ERR(regmap));
 800                 return PTR_ERR(regmap);
 801         }
 802
 803         return rv3029_probe(&client->dev, regmap, client->irq, client->name);
 804 }
 805
 806 static struct i2c_driver rv3029_driver = {
 807         .driver = {
 808                 .name = "rtc-rv3029c2",
 809         },
 810         .probe          = rv3029_i2c_probe,
 811         .id_table       = rv3029_id,
 812 };
 813
 814 static int rv3029_register_driver(void)
 815 {
 816         return i2c_add_driver(&rv3029_driver);
 817 }
 818
 819 static void rv3029_unregister_driver(void)
 820 {
 821         i2c_del_driver(&rv3029_driver);
 822 }
 823
 824 #else
 825
 826 static int rv3029_register_driver(void)
 827 {
 828         return 0;
 829 }
 830
 831 static void rv3029_unregister_driver(void)
 832 {
 833 }
 834
 835 #endif
 836
 837 #if IS_ENABLED(CONFIG_SPI_MASTER)
 838
 839 static int rv3049_probe(struct spi_device *spi)
 840 {
 841         static const struct regmap_config config = {
 842                 .reg_bits = 8,
 843                 .val_bits = 8,
 844         };
 845         struct regmap *regmap;
 846
 847         regmap = devm_regmap_init_spi(spi, &config);
 848         if (IS_ERR(regmap)) {
 849                 dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
 850                         __func__, PTR_ERR(regmap));
 851                 return PTR_ERR(regmap);
 852         }
 853
 854         return rv3029_probe(&spi->dev, regmap, spi->irq, "rv3049");
 855 }
 856
 857 static struct spi_driver rv3049_driver = {
 858         .driver = {
 859                 .name    = "rv3049",
 860         },
 861         .probe   = rv3049_probe,
 862 };
 863
 864 static int rv3049_register_driver(void)
 865 {
 866         return spi_register_driver(&rv3049_driver);
 867 }
 868
 869 static void rv3049_unregister_driver(void)
 870 {
 871         spi_unregister_driver(&rv3049_driver);
 872 }
 873
 874 #else
 875
 876 static int rv3049_register_driver(void)
 877 {
 878         return 0;
 879 }
 880
 881 static void rv3049_unregister_driver(void)
 882 {
 883 }
 884
 885 #endif
 886
 887 static int __init rv30x9_init(void)
 888 {
 889         int ret;
 890
 891         ret = rv3029_register_driver();
 892         if (ret) {
 893                 pr_err("Failed to register rv3029 driver: %d\n", ret);
 894                 return ret;
 895         }
 896
 897         ret = rv3049_register_driver();
 898         if (ret) {
 899                 pr_err("Failed to register rv3049 driver: %d\n", ret);
 900                 rv3029_unregister_driver();
 901         }
 902
 903         return ret;
 904 }
 905 module_init(rv30x9_init)
 906
 907 static void __exit rv30x9_exit(void)
 908 {
 909         rv3049_unregister_driver();
 910         rv3029_unregister_driver();
 911 }
 912 module_exit(rv30x9_exit)
 913
 914 MODULE_AUTHOR("Gregory Hermant <gregory.hermant@calao-systems.com>");
 915 MODULE_AUTHOR("Michael Buesch <m@bues.ch>");
 916 MODULE_DESCRIPTION("Micro Crystal RV3029/RV3049 RTC driver");
 917 MODULE_LICENSE("GPL");
 918 MODULE_ALIAS("spi:rv3049");