drivers/rtc/rtc-da9063.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Real time clock device driver for DA9063
   4  * Copyright (C) 2013-2015  Dialog Semiconductor Ltd.
   5  */
   6
   7 #include <linux/delay.h>
   8 #include <linux/init.h>
   9 #include <linux/interrupt.h>
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/regmap.h>
  15 #include <linux/rtc.h>
  16 #include <linux/slab.h>
  17
  18 #include <linux/mfd/da9062/registers.h>
  19 #include <linux/mfd/da9063/registers.h>
  20 #include <linux/mfd/da9063/core.h>
  21
  22 #define YEARS_TO_DA9063(year)           ((year) - 100)
  23 #define MONTHS_TO_DA9063(month)         ((month) + 1)
  24 #define YEARS_FROM_DA9063(year)         ((year) + 100)
  25 #define MONTHS_FROM_DA9063(month)       ((month) - 1)
  26
  27 enum {
  28         RTC_SEC = 0,
  29         RTC_MIN = 1,
  30         RTC_HOUR = 2,
  31         RTC_DAY = 3,
  32         RTC_MONTH = 4,
  33         RTC_YEAR = 5,
  34         RTC_DATA_LEN
  35 };
  36
  37 struct da9063_compatible_rtc_regmap {
  38         /* REGS */
  39         int rtc_enable_reg;
  40         int rtc_enable_32k_crystal_reg;
  41         int rtc_alarm_secs_reg;
  42         int rtc_alarm_year_reg;
  43         int rtc_count_secs_reg;
  44         int rtc_count_year_reg;
  45         int rtc_event_reg;
  46         /* MASKS */
  47         int rtc_enable_mask;
  48         int rtc_crystal_mask;
  49         int rtc_event_alarm_mask;
  50         int rtc_alarm_on_mask;
  51         int rtc_alarm_status_mask;
  52         int rtc_tick_on_mask;
  53         int rtc_ready_to_read_mask;
  54         int rtc_count_sec_mask;
  55         int rtc_count_min_mask;
  56         int rtc_count_hour_mask;
  57         int rtc_count_day_mask;
  58         int rtc_count_month_mask;
  59         int rtc_count_year_mask;
  60         /* ALARM CONFIG */
  61         int rtc_data_start;
  62         int rtc_alarm_len;
  63 };
  64
  65 struct da9063_compatible_rtc {
  66         struct rtc_device *rtc_dev;
  67         struct rtc_time alarm_time;
  68         struct regmap *regmap;
  69         const struct da9063_compatible_rtc_regmap *config;
  70         bool rtc_sync;
  71 };
  72
  73 static const struct da9063_compatible_rtc_regmap da9063_ad_regs = {
  74         /* REGS */
  75         .rtc_enable_reg             = DA9063_REG_CONTROL_E,
  76         .rtc_alarm_secs_reg         = DA9063_AD_REG_ALARM_MI,
  77         .rtc_alarm_year_reg         = DA9063_AD_REG_ALARM_Y,
  78         .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
  79         .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
  80         .rtc_event_reg              = DA9063_REG_EVENT_A,
  81         /* MASKS */
  82         .rtc_enable_mask            = DA9063_RTC_EN,
  83         .rtc_crystal_mask           = DA9063_CRYSTAL,
  84         .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
  85         .rtc_event_alarm_mask       = DA9063_E_ALARM,
  86         .rtc_alarm_on_mask          = DA9063_ALARM_ON,
  87         .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
  88                                       DA9063_ALARM_STATUS_TICK,
  89         .rtc_tick_on_mask           = DA9063_TICK_ON,
  90         .rtc_ready_to_read_mask     = DA9063_RTC_READ,
  91         .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
  92         .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
  93         .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
  94         .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
  95         .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
  96         .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
  97         /* ALARM CONFIG */
  98         .rtc_data_start             = RTC_MIN,
  99         .rtc_alarm_len              = RTC_DATA_LEN - 1,
 100 };
 101
 102 static const struct da9063_compatible_rtc_regmap da9063_bb_regs = {
 103         /* REGS */
 104         .rtc_enable_reg             = DA9063_REG_CONTROL_E,
 105         .rtc_alarm_secs_reg         = DA9063_BB_REG_ALARM_S,
 106         .rtc_alarm_year_reg         = DA9063_BB_REG_ALARM_Y,
 107         .rtc_count_secs_reg         = DA9063_REG_COUNT_S,
 108         .rtc_count_year_reg         = DA9063_REG_COUNT_Y,
 109         .rtc_event_reg              = DA9063_REG_EVENT_A,
 110         /* MASKS */
 111         .rtc_enable_mask            = DA9063_RTC_EN,
 112         .rtc_crystal_mask           = DA9063_CRYSTAL,
 113         .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
 114         .rtc_event_alarm_mask       = DA9063_E_ALARM,
 115         .rtc_alarm_on_mask          = DA9063_ALARM_ON,
 116         .rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
 117                                       DA9063_ALARM_STATUS_TICK,
 118         .rtc_tick_on_mask           = DA9063_TICK_ON,
 119         .rtc_ready_to_read_mask     = DA9063_RTC_READ,
 120         .rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
 121         .rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
 122         .rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
 123         .rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
 124         .rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
 125         .rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
 126         /* ALARM CONFIG */
 127         .rtc_data_start             = RTC_SEC,
 128         .rtc_alarm_len              = RTC_DATA_LEN,
 129 };
 130
 131 static const struct da9063_compatible_rtc_regmap da9062_aa_regs = {
 132         /* REGS */
 133         .rtc_enable_reg             = DA9062AA_CONTROL_E,
 134         .rtc_alarm_secs_reg         = DA9062AA_ALARM_S,
 135         .rtc_alarm_year_reg         = DA9062AA_ALARM_Y,
 136         .rtc_count_secs_reg         = DA9062AA_COUNT_S,
 137         .rtc_count_year_reg         = DA9062AA_COUNT_Y,
 138         .rtc_event_reg              = DA9062AA_EVENT_A,
 139         /* MASKS */
 140         .rtc_enable_mask            = DA9062AA_RTC_EN_MASK,
 141         .rtc_crystal_mask           = DA9062AA_CRYSTAL_MASK,
 142         .rtc_enable_32k_crystal_reg = DA9062AA_EN_32K,
 143         .rtc_event_alarm_mask       = DA9062AA_M_ALARM_MASK,
 144         .rtc_alarm_on_mask          = DA9062AA_ALARM_ON_MASK,
 145         .rtc_alarm_status_mask      = (0x02 << 6),
 146         .rtc_tick_on_mask           = DA9062AA_TICK_ON_MASK,
 147         .rtc_ready_to_read_mask     = DA9062AA_RTC_READ_MASK,
 148         .rtc_count_sec_mask         = DA9062AA_COUNT_SEC_MASK,
 149         .rtc_count_min_mask         = DA9062AA_COUNT_MIN_MASK,
 150         .rtc_count_hour_mask        = DA9062AA_COUNT_HOUR_MASK,
 151         .rtc_count_day_mask         = DA9062AA_COUNT_DAY_MASK,
 152         .rtc_count_month_mask       = DA9062AA_COUNT_MONTH_MASK,
 153         .rtc_count_year_mask        = DA9062AA_COUNT_YEAR_MASK,
 154         /* ALARM CONFIG */
 155         .rtc_data_start             = RTC_SEC,
 156         .rtc_alarm_len              = RTC_DATA_LEN,
 157 };
 158
 159 static const struct of_device_id da9063_compatible_reg_id_table[] = {
 160         { .compatible = "dlg,da9063-rtc", .data = &da9063_bb_regs },
 161         { .compatible = "dlg,da9062-rtc", .data = &da9062_aa_regs },
 162         { },
 163 };
 164 MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);
 165
 166 static void da9063_data_to_tm(u8 *data, struct rtc_time *tm,
 167                               struct da9063_compatible_rtc *rtc)
 168 {
 169         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 170
 171         tm->tm_sec  = data[RTC_SEC]  & config->rtc_count_sec_mask;
 172         tm->tm_min  = data[RTC_MIN]  & config->rtc_count_min_mask;
 173         tm->tm_hour = data[RTC_HOUR] & config->rtc_count_hour_mask;
 174         tm->tm_mday = data[RTC_DAY]  & config->rtc_count_day_mask;
 175         tm->tm_mon  = MONTHS_FROM_DA9063(data[RTC_MONTH] &
 176                                          config->rtc_count_month_mask);
 177         tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
 178                                         config->rtc_count_year_mask);
 179 }
 180
 181 static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
 182                               struct da9063_compatible_rtc *rtc)
 183 {
 184         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 185
 186         data[RTC_SEC]   = tm->tm_sec & config->rtc_count_sec_mask;
 187         data[RTC_MIN]   = tm->tm_min & config->rtc_count_min_mask;
 188         data[RTC_HOUR]  = tm->tm_hour & config->rtc_count_hour_mask;
 189         data[RTC_DAY]   = tm->tm_mday & config->rtc_count_day_mask;
 190         data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
 191                                 config->rtc_count_month_mask;
 192         data[RTC_YEAR]  = YEARS_TO_DA9063(tm->tm_year) &
 193                                 config->rtc_count_year_mask;
 194 }
 195
 196 static int da9063_rtc_stop_alarm(struct device *dev)
 197 {
 198         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 199         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 200
 201         return regmap_update_bits(rtc->regmap,
 202                                   config->rtc_alarm_year_reg,
 203                                   config->rtc_alarm_on_mask,
 204                                   0);
 205 }
 206
 207 static int da9063_rtc_start_alarm(struct device *dev)
 208 {
 209         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 210         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 211
 212         return regmap_update_bits(rtc->regmap,
 213                                   config->rtc_alarm_year_reg,
 214                                   config->rtc_alarm_on_mask,
 215                                   config->rtc_alarm_on_mask);
 216 }
 217
 218 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
 219 {
 220         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 221         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 222         unsigned long tm_secs;
 223         unsigned long al_secs;
 224         u8 data[RTC_DATA_LEN];
 225         int ret;
 226
 227         ret = regmap_bulk_read(rtc->regmap,
 228                                config->rtc_count_secs_reg,
 229                                data, RTC_DATA_LEN);
 230         if (ret < 0) {
 231                 dev_err(dev, "Failed to read RTC time data: %d\n", ret);
 232                 return ret;
 233         }
 234
 235         if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
 236                 dev_dbg(dev, "RTC not yet ready to be read by the host\n");
 237                 return -EINVAL;
 238         }
 239
 240         da9063_data_to_tm(data, tm, rtc);
 241
 242         tm_secs = rtc_tm_to_time64(tm);
 243         al_secs = rtc_tm_to_time64(&rtc->alarm_time);
 244
 245         /* handle the rtc synchronisation delay */
 246         if (rtc->rtc_sync && al_secs - tm_secs == 1)
 247                 memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
 248         else
 249                 rtc->rtc_sync = false;
 250
 251         return 0;
 252 }
 253
 254 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
 255 {
 256         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 257         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 258         u8 data[RTC_DATA_LEN];
 259         int ret;
 260
 261         da9063_tm_to_data(tm, data, rtc);
 262         ret = regmap_bulk_write(rtc->regmap,
 263                                 config->rtc_count_secs_reg,
 264                                 data, RTC_DATA_LEN);
 265         if (ret < 0)
 266                 dev_err(dev, "Failed to set RTC time data: %d\n", ret);
 267
 268         return ret;
 269 }
 270
 271 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 272 {
 273         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 274         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 275         u8 data[RTC_DATA_LEN];
 276         int ret;
 277         unsigned int val;
 278
 279         data[RTC_SEC] = 0;
 280         ret = regmap_bulk_read(rtc->regmap,
 281                                config->rtc_alarm_secs_reg,
 282                                &data[config->rtc_data_start],
 283                                config->rtc_alarm_len);
 284         if (ret < 0)
 285                 return ret;
 286
 287         da9063_data_to_tm(data, &alrm->time, rtc);
 288
 289         alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);
 290
 291         ret = regmap_read(rtc->regmap,
 292                           config->rtc_event_reg,
 293                           &val);
 294         if (ret < 0)
 295                 return ret;
 296
 297         if (val & config->rtc_event_alarm_mask)
 298                 alrm->pending = 1;
 299         else
 300                 alrm->pending = 0;
 301
 302         return 0;
 303 }
 304
 305 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 306 {
 307         struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
 308         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 309         u8 data[RTC_DATA_LEN];
 310         int ret;
 311
 312         da9063_tm_to_data(&alrm->time, data, rtc);
 313
 314         ret = da9063_rtc_stop_alarm(dev);
 315         if (ret < 0) {
 316                 dev_err(dev, "Failed to stop alarm: %d\n", ret);
 317                 return ret;
 318         }
 319
 320         ret = regmap_bulk_write(rtc->regmap,
 321                                 config->rtc_alarm_secs_reg,
 322                                 &data[config->rtc_data_start],
 323                                 config->rtc_alarm_len);
 324         if (ret < 0) {
 325                 dev_err(dev, "Failed to write alarm: %d\n", ret);
 326                 return ret;
 327         }
 328
 329         da9063_data_to_tm(data, &rtc->alarm_time, rtc);
 330
 331         if (alrm->enabled) {
 332                 ret = da9063_rtc_start_alarm(dev);
 333                 if (ret < 0) {
 334                         dev_err(dev, "Failed to start alarm: %d\n", ret);
 335                         return ret;
 336                 }
 337         }
 338
 339         return ret;
 340 }
 341
 342 static int da9063_rtc_alarm_irq_enable(struct device *dev,
 343                                        unsigned int enabled)
 344 {
 345         if (enabled)
 346                 return da9063_rtc_start_alarm(dev);
 347         else
 348                 return da9063_rtc_stop_alarm(dev);
 349 }
 350
 351 static irqreturn_t da9063_alarm_event(int irq, void *data)
 352 {
 353         struct da9063_compatible_rtc *rtc = data;
 354         const struct da9063_compatible_rtc_regmap *config = rtc->config;
 355
 356         regmap_update_bits(rtc->regmap,
 357                            config->rtc_alarm_year_reg,
 358                            config->rtc_alarm_on_mask,
 359                            0);
 360
 361         rtc->rtc_sync = true;
 362         rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
 363
 364         return IRQ_HANDLED;
 365 }
 366
 367 static const struct rtc_class_ops da9063_rtc_ops = {
 368         .read_time = da9063_rtc_read_time,
 369         .set_time = da9063_rtc_set_time,
 370         .read_alarm = da9063_rtc_read_alarm,
 371         .set_alarm = da9063_rtc_set_alarm,
 372         .alarm_irq_enable = da9063_rtc_alarm_irq_enable,
 373 };
 374
 375 static int da9063_rtc_probe(struct platform_device *pdev)
 376 {
 377         struct da9063_compatible_rtc *rtc;
 378         const struct da9063_compatible_rtc_regmap *config;
 379         const struct of_device_id *match;
 380         int irq_alarm;
 381         u8 data[RTC_DATA_LEN];
 382         int ret;
 383
 384         if (!pdev->dev.of_node)
 385                 return -ENXIO;
 386
 387         match = of_match_node(da9063_compatible_reg_id_table,
 388                               pdev->dev.of_node);
 389
 390         rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 391         if (!rtc)
 392                 return -ENOMEM;
 393
 394         rtc->config = match->data;
 395         if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
 396                 struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
 397
 398                 if (chip->variant_code == PMIC_DA9063_AD)
 399                         rtc->config = &da9063_ad_regs;
 400         }
 401
 402         rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
 403         if (!rtc->regmap) {
 404                 dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
 405                 return -ENXIO;
 406         }
 407
 408         config = rtc->config;
 409         ret = regmap_update_bits(rtc->regmap,
 410                                  config->rtc_enable_reg,
 411                                  config->rtc_enable_mask,
 412                                  config->rtc_enable_mask);
 413         if (ret < 0) {
 414                 dev_err(&pdev->dev, "Failed to enable RTC\n");
 415                 return ret;
 416         }
 417
 418         ret = regmap_update_bits(rtc->regmap,
 419                                  config->rtc_enable_32k_crystal_reg,
 420                                  config->rtc_crystal_mask,
 421                                  config->rtc_crystal_mask);
 422         if (ret < 0) {
 423                 dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
 424                 return ret;
 425         }
 426
 427         ret = regmap_update_bits(rtc->regmap,
 428                                  config->rtc_alarm_secs_reg,
 429                                  config->rtc_alarm_status_mask,
 430                                  0);
 431         if (ret < 0) {
 432                 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
 433                 return ret;
 434         }
 435
 436         ret = regmap_update_bits(rtc->regmap,
 437                                  config->rtc_alarm_secs_reg,
 438                                  DA9063_ALARM_STATUS_ALARM,
 439                                  DA9063_ALARM_STATUS_ALARM);
 440         if (ret < 0) {
 441                 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
 442                 return ret;
 443         }
 444
 445         ret = regmap_update_bits(rtc->regmap,
 446                                  config->rtc_alarm_year_reg,
 447                                  config->rtc_tick_on_mask,
 448                                  0);
 449         if (ret < 0) {
 450                 dev_err(&pdev->dev, "Failed to disable TICKs\n");
 451                 return ret;
 452         }
 453
 454         data[RTC_SEC] = 0;
 455         ret = regmap_bulk_read(rtc->regmap,
 456                                config->rtc_alarm_secs_reg,
 457                                &data[config->rtc_data_start],
 458                                config->rtc_alarm_len);
 459         if (ret < 0) {
 460                 dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
 461                         ret);
 462                 return ret;
 463         }
 464
 465         platform_set_drvdata(pdev, rtc);
 466
 467         rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
 468         if (IS_ERR(rtc->rtc_dev))
 469                 return PTR_ERR(rtc->rtc_dev);
 470
 471         rtc->rtc_dev->ops = &da9063_rtc_ops;
 472         rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
 473         rtc->rtc_dev->range_max = RTC_TIMESTAMP_END_2063;
 474
 475         da9063_data_to_tm(data, &rtc->alarm_time, rtc);
 476         rtc->rtc_sync = false;
 477
 478         /*
 479          * TODO: some models have alarms on a minute boundary but still support
 480          * real hardware interrupts. Add this once the core supports it.
 481          */
 482         if (config->rtc_data_start != RTC_SEC)
 483                 rtc->rtc_dev->uie_unsupported = 1;
 484
 485         irq_alarm = platform_get_irq_byname(pdev, "ALARM");
 486         if (irq_alarm < 0)
 487                 return irq_alarm;
 488
 489         ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
 490                                         da9063_alarm_event,
 491                                         IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 492                                         "ALARM", rtc);
 493         if (ret)
 494                 dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
 495                         irq_alarm, ret);
 496
 497         return devm_rtc_register_device(rtc->rtc_dev);
 498 }
 499
 500 static struct platform_driver da9063_rtc_driver = {
 501         .probe          = da9063_rtc_probe,
 502         .driver         = {
 503                 .name   = DA9063_DRVNAME_RTC,
 504                 .of_match_table = da9063_compatible_reg_id_table,
 505         },
 506 };
 507
 508 module_platform_driver(da9063_rtc_driver);
 509
 510 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
 511 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
 512 MODULE_LICENSE("GPL");
 513 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);