drivers/rtc/rtc-s3c.c

   1 /* drivers/rtc/rtc-s3c.c
   2  *
   3  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com/
   5  *
   6  * Copyright (c) 2004,2006 Simtec Electronics
   7  *      Ben Dooks, <ben@simtec.co.uk>
   8  *      http://armlinux.simtec.co.uk/
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  * S3C2410/S3C2440/S3C24XX Internal RTC Driver
  15 */
  16
  17 #include <linux/module.h>
  18 #include <linux/fs.h>
  19 #include <linux/string.h>
  20 #include <linux/init.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/rtc.h>
  24 #include <linux/bcd.h>
  25 #include <linux/clk.h>
  26 #include <linux/log2.h>
  27 #include <linux/slab.h>
  28 #include <linux/of.h>
  29 #include <linux/uaccess.h>
  30 #include <linux/io.h>
  31
  32 #include <asm/irq.h>
  33 #include "rtc-s3c.h"
  34
  35 struct s3c_rtc {
  36         struct device *dev;
  37         struct rtc_device *rtc;
  38
  39         void __iomem *base;
  40         struct clk *rtc_clk;
  41         struct clk *rtc_src_clk;
  42         bool enabled;
  43
  44         struct s3c_rtc_data *data;
  45
  46         int irq_alarm;
  47         int irq_tick;
  48
  49         spinlock_t pie_lock;
  50         spinlock_t alarm_clk_lock;
  51
  52         int ticnt_save, ticnt_en_save;
  53         bool wake_en;
  54 };
  55
  56 struct s3c_rtc_data {
  57         int max_user_freq;
  58         bool needs_src_clk;
  59
  60         void (*irq_handler) (struct s3c_rtc *info, int mask);
  61         void (*set_freq) (struct s3c_rtc *info, int freq);
  62         void (*enable_tick) (struct s3c_rtc *info, struct seq_file *seq);
  63         void (*select_tick_clk) (struct s3c_rtc *info);
  64         void (*save_tick_cnt) (struct s3c_rtc *info);
  65         void (*restore_tick_cnt) (struct s3c_rtc *info);
  66         void (*enable) (struct s3c_rtc *info);
  67         void (*disable) (struct s3c_rtc *info);
  68 };
  69
  70 static void s3c_rtc_alarm_clk_enable(struct s3c_rtc *info, bool enable)
  71 {
  72         unsigned long irq_flags;
  73
  74         spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
  75         if (enable) {
  76                 if (!info->enabled) {
  77                         clk_enable(info->rtc_clk);
  78                         if (info->data->needs_src_clk)
  79                                 clk_enable(info->rtc_src_clk);
  80                         info->enabled = true;
  81                 }
  82         } else {
  83                 if (info->enabled) {
  84                         if (info->data->needs_src_clk)
  85                                 clk_disable(info->rtc_src_clk);
  86                         clk_disable(info->rtc_clk);
  87                         info->enabled = false;
  88                 }
  89         }
  90         spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
  91 }
  92
  93 /* IRQ Handlers */
  94 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
  95 {
  96         struct s3c_rtc *info = (struct s3c_rtc *)id;
  97
  98         if (info->data->irq_handler)
  99                 info->data->irq_handler(info, S3C2410_INTP_TIC);
 100
 101         return IRQ_HANDLED;
 102 }
 103
 104 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
 105 {
 106         struct s3c_rtc *info = (struct s3c_rtc *)id;
 107
 108         if (info->data->irq_handler)
 109                 info->data->irq_handler(info, S3C2410_INTP_ALM);
 110
 111         return IRQ_HANDLED;
 112 }
 113
 114 /* Update control registers */
 115 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
 116 {
 117         struct s3c_rtc *info = dev_get_drvdata(dev);
 118         unsigned int tmp;
 119
 120         dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
 121
 122         clk_enable(info->rtc_clk);
 123         if (info->data->needs_src_clk)
 124                 clk_enable(info->rtc_src_clk);
 125         tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
 126
 127         if (enabled)
 128                 tmp |= S3C2410_RTCALM_ALMEN;
 129
 130         writeb(tmp, info->base + S3C2410_RTCALM);
 131         if (info->data->needs_src_clk)
 132                 clk_disable(info->rtc_src_clk);
 133         clk_disable(info->rtc_clk);
 134
 135         s3c_rtc_alarm_clk_enable(info, enabled);
 136
 137         return 0;
 138 }
 139
 140 /* Set RTC frequency */
 141 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
 142 {
 143         if (!is_power_of_2(freq))
 144                 return -EINVAL;
 145
 146         clk_enable(info->rtc_clk);
 147         if (info->data->needs_src_clk)
 148                 clk_enable(info->rtc_src_clk);
 149         spin_lock_irq(&info->pie_lock);
 150
 151         if (info->data->set_freq)
 152                 info->data->set_freq(info, freq);
 153
 154         spin_unlock_irq(&info->pie_lock);
 155         if (info->data->needs_src_clk)
 156                 clk_disable(info->rtc_src_clk);
 157         clk_disable(info->rtc_clk);
 158
 159         return 0;
 160 }
 161
 162 /* Time read/write */
 163 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 164 {
 165         struct s3c_rtc *info = dev_get_drvdata(dev);
 166         unsigned int have_retried = 0;
 167
 168         clk_enable(info->rtc_clk);
 169         if (info->data->needs_src_clk)
 170                 clk_enable(info->rtc_src_clk);
 171
 172  retry_get_time:
 173         rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
 174         rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
 175         rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
 176         rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
 177         rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
 178         rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
 179
 180         /* the only way to work out whether the system was mid-update
 181          * when we read it is to check the second counter, and if it
 182          * is zero, then we re-try the entire read
 183          */
 184
 185         if (rtc_tm->tm_sec == 0 && !have_retried) {
 186                 have_retried = 1;
 187                 goto retry_get_time;
 188         }
 189
 190         rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
 191         rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
 192         rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
 193         rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
 194         rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
 195         rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
 196
 197         rtc_tm->tm_year += 100;
 198
 199         dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n",
 200                  1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
 201                  rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
 202
 203         rtc_tm->tm_mon -= 1;
 204
 205         if (info->data->needs_src_clk)
 206                 clk_disable(info->rtc_src_clk);
 207         clk_disable(info->rtc_clk);
 208
 209         return rtc_valid_tm(rtc_tm);
 210 }
 211
 212 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
 213 {
 214         struct s3c_rtc *info = dev_get_drvdata(dev);
 215         int year = tm->tm_year - 100;
 216
 217         dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n",
 218                  1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
 219                  tm->tm_hour, tm->tm_min, tm->tm_sec);
 220
 221         /* we get around y2k by simply not supporting it */
 222
 223         if (year < 0 || year >= 100) {
 224                 dev_err(dev, "rtc only supports 100 years\n");
 225                 return -EINVAL;
 226         }
 227
 228         clk_enable(info->rtc_clk);
 229         if (info->data->needs_src_clk)
 230                 clk_enable(info->rtc_src_clk);
 231
 232         writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
 233         writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
 234         writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
 235         writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
 236         writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
 237         writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
 238
 239         if (info->data->needs_src_clk)
 240                 clk_disable(info->rtc_src_clk);
 241         clk_disable(info->rtc_clk);
 242
 243         return 0;
 244 }
 245
 246 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
 247 {
 248         struct s3c_rtc *info = dev_get_drvdata(dev);
 249         struct rtc_time *alm_tm = &alrm->time;
 250         unsigned int alm_en;
 251
 252         clk_enable(info->rtc_clk);
 253         if (info->data->needs_src_clk)
 254                 clk_enable(info->rtc_src_clk);
 255
 256         alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
 257         alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
 258         alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
 259         alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
 260         alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
 261         alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
 262
 263         alm_en = readb(info->base + S3C2410_RTCALM);
 264
 265         alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
 266
 267         dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 268                  alm_en,
 269                  1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
 270                  alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
 271
 272
 273         /* decode the alarm enable field */
 274
 275         if (alm_en & S3C2410_RTCALM_SECEN)
 276                 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
 277         else
 278                 alm_tm->tm_sec = -1;
 279
 280         if (alm_en & S3C2410_RTCALM_MINEN)
 281                 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
 282         else
 283                 alm_tm->tm_min = -1;
 284
 285         if (alm_en & S3C2410_RTCALM_HOUREN)
 286                 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
 287         else
 288                 alm_tm->tm_hour = -1;
 289
 290         if (alm_en & S3C2410_RTCALM_DAYEN)
 291                 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
 292         else
 293                 alm_tm->tm_mday = -1;
 294
 295         if (alm_en & S3C2410_RTCALM_MONEN) {
 296                 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
 297                 alm_tm->tm_mon -= 1;
 298         } else {
 299                 alm_tm->tm_mon = -1;
 300         }
 301
 302         if (alm_en & S3C2410_RTCALM_YEAREN)
 303                 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
 304         else
 305                 alm_tm->tm_year = -1;
 306
 307         if (info->data->needs_src_clk)
 308                 clk_disable(info->rtc_src_clk);
 309         clk_disable(info->rtc_clk);
 310
 311         return 0;
 312 }
 313
 314 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
 315 {
 316         struct s3c_rtc *info = dev_get_drvdata(dev);
 317         struct rtc_time *tm = &alrm->time;
 318         unsigned int alrm_en;
 319
 320         clk_enable(info->rtc_clk);
 321         if (info->data->needs_src_clk)
 322                 clk_enable(info->rtc_src_clk);
 323
 324         dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 325                  alrm->enabled,
 326                  1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
 327                  tm->tm_hour, tm->tm_min, tm->tm_sec);
 328
 329         alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
 330         writeb(0x00, info->base + S3C2410_RTCALM);
 331
 332         if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
 333                 alrm_en |= S3C2410_RTCALM_SECEN;
 334                 writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
 335         }
 336
 337         if (tm->tm_min < 60 && tm->tm_min >= 0) {
 338                 alrm_en |= S3C2410_RTCALM_MINEN;
 339                 writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
 340         }
 341
 342         if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
 343                 alrm_en |= S3C2410_RTCALM_HOUREN;
 344                 writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
 345         }
 346
 347         dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
 348
 349         writeb(alrm_en, info->base + S3C2410_RTCALM);
 350
 351         s3c_rtc_setaie(dev, alrm->enabled);
 352
 353         if (info->data->needs_src_clk)
 354                 clk_disable(info->rtc_src_clk);
 355         clk_disable(info->rtc_clk);
 356
 357         return 0;
 358 }
 359
 360 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
 361 {
 362         struct s3c_rtc *info = dev_get_drvdata(dev);
 363
 364         clk_enable(info->rtc_clk);
 365         if (info->data->needs_src_clk)
 366                 clk_enable(info->rtc_src_clk);
 367
 368         if (info->data->enable_tick)
 369                 info->data->enable_tick(info, seq);
 370
 371         if (info->data->needs_src_clk)
 372                 clk_disable(info->rtc_src_clk);
 373         clk_disable(info->rtc_clk);
 374
 375         return 0;
 376 }
 377
 378 static const struct rtc_class_ops s3c_rtcops = {
 379         .read_time      = s3c_rtc_gettime,
 380         .set_time       = s3c_rtc_settime,
 381         .read_alarm     = s3c_rtc_getalarm,
 382         .set_alarm      = s3c_rtc_setalarm,
 383         .proc           = s3c_rtc_proc,
 384         .alarm_irq_enable = s3c_rtc_setaie,
 385 };
 386
 387 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
 388 {
 389         unsigned int con, tmp;
 390
 391         clk_enable(info->rtc_clk);
 392         if (info->data->needs_src_clk)
 393                 clk_enable(info->rtc_src_clk);
 394
 395         con = readw(info->base + S3C2410_RTCCON);
 396         /* re-enable the device, and check it is ok */
 397         if ((con & S3C2410_RTCCON_RTCEN) == 0) {
 398                 dev_info(info->dev, "rtc disabled, re-enabling\n");
 399
 400                 tmp = readw(info->base + S3C2410_RTCCON);
 401                 writew(tmp | S3C2410_RTCCON_RTCEN,
 402                         info->base + S3C2410_RTCCON);
 403         }
 404
 405         if (con & S3C2410_RTCCON_CNTSEL) {
 406                 dev_info(info->dev, "removing RTCCON_CNTSEL\n");
 407
 408                 tmp = readw(info->base + S3C2410_RTCCON);
 409                 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
 410                         info->base + S3C2410_RTCCON);
 411         }
 412
 413         if (con & S3C2410_RTCCON_CLKRST) {
 414                 dev_info(info->dev, "removing RTCCON_CLKRST\n");
 415
 416                 tmp = readw(info->base + S3C2410_RTCCON);
 417                 writew(tmp & ~S3C2410_RTCCON_CLKRST,
 418                         info->base + S3C2410_RTCCON);
 419         }
 420
 421         if (info->data->needs_src_clk)
 422                 clk_disable(info->rtc_src_clk);
 423         clk_disable(info->rtc_clk);
 424 }
 425
 426 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
 427 {
 428         unsigned int con;
 429
 430         clk_enable(info->rtc_clk);
 431         if (info->data->needs_src_clk)
 432                 clk_enable(info->rtc_src_clk);
 433
 434         con = readw(info->base + S3C2410_RTCCON);
 435         con &= ~S3C2410_RTCCON_RTCEN;
 436         writew(con, info->base + S3C2410_RTCCON);
 437
 438         con = readb(info->base + S3C2410_TICNT);
 439         con &= ~S3C2410_TICNT_ENABLE;
 440         writeb(con, info->base + S3C2410_TICNT);
 441
 442         if (info->data->needs_src_clk)
 443                 clk_disable(info->rtc_src_clk);
 444         clk_disable(info->rtc_clk);
 445 }
 446
 447 static void s3c6410_rtc_disable(struct s3c_rtc *info)
 448 {
 449         unsigned int con;
 450
 451         clk_enable(info->rtc_clk);
 452         if (info->data->needs_src_clk)
 453                 clk_enable(info->rtc_src_clk);
 454
 455         con = readw(info->base + S3C2410_RTCCON);
 456         con &= ~S3C64XX_RTCCON_TICEN;
 457         con &= ~S3C2410_RTCCON_RTCEN;
 458         writew(con, info->base + S3C2410_RTCCON);
 459
 460         if (info->data->needs_src_clk)
 461                 clk_disable(info->rtc_src_clk);
 462         clk_disable(info->rtc_clk);
 463 }
 464
 465 static int s3c_rtc_remove(struct platform_device *pdev)
 466 {
 467         struct s3c_rtc *info = platform_get_drvdata(pdev);
 468
 469         s3c_rtc_setaie(info->dev, 0);
 470
 471         clk_unprepare(info->rtc_clk);
 472         info->rtc_clk = NULL;
 473
 474         return 0;
 475 }
 476
 477 static const struct of_device_id s3c_rtc_dt_match[];
 478
 479 static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
 480 {
 481         const struct of_device_id *match;
 482
 483         match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
 484         return (struct s3c_rtc_data *)match->data;
 485 }
 486
 487 static int s3c_rtc_probe(struct platform_device *pdev)
 488 {
 489         struct s3c_rtc *info = NULL;
 490         struct rtc_time rtc_tm;
 491         struct resource *res;
 492         int ret;
 493
 494         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 495         if (!info)
 496                 return -ENOMEM;
 497
 498         /* find the IRQs */
 499         info->irq_tick = platform_get_irq(pdev, 1);
 500         if (info->irq_tick < 0) {
 501                 dev_err(&pdev->dev, "no irq for rtc tick\n");
 502                 return info->irq_tick;
 503         }
 504
 505         info->dev = &pdev->dev;
 506         info->data = s3c_rtc_get_data(pdev);
 507         if (!info->data) {
 508                 dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
 509                 return -EINVAL;
 510         }
 511         spin_lock_init(&info->pie_lock);
 512         spin_lock_init(&info->alarm_clk_lock);
 513
 514         platform_set_drvdata(pdev, info);
 515
 516         info->irq_alarm = platform_get_irq(pdev, 0);
 517         if (info->irq_alarm < 0) {
 518                 dev_err(&pdev->dev, "no irq for alarm\n");
 519                 return info->irq_alarm;
 520         }
 521
 522         dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
 523                  info->irq_tick, info->irq_alarm);
 524
 525         /* get the memory region */
 526         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 527         info->base = devm_ioremap_resource(&pdev->dev, res);
 528         if (IS_ERR(info->base))
 529                 return PTR_ERR(info->base);
 530
 531         info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
 532         if (IS_ERR(info->rtc_clk)) {
 533                 dev_err(&pdev->dev, "failed to find rtc clock\n");
 534                 return PTR_ERR(info->rtc_clk);
 535         }
 536         clk_prepare_enable(info->rtc_clk);
 537
 538         info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
 539         if (IS_ERR(info->rtc_src_clk)) {
 540                 dev_err(&pdev->dev, "failed to find rtc source clock\n");
 541                 return PTR_ERR(info->rtc_src_clk);
 542         }
 543         clk_prepare_enable(info->rtc_src_clk);
 544
 545
 546         /* check to see if everything is setup correctly */
 547         if (info->data->enable)
 548                 info->data->enable(info);
 549
 550         dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
 551                  readw(info->base + S3C2410_RTCCON));
 552
 553         device_init_wakeup(&pdev->dev, 1);
 554
 555         /* register RTC and exit */
 556         info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
 557                                   THIS_MODULE);
 558         if (IS_ERR(info->rtc)) {
 559                 dev_err(&pdev->dev, "cannot attach rtc\n");
 560                 ret = PTR_ERR(info->rtc);
 561                 goto err_nortc;
 562         }
 563
 564         ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
 565                           0,  "s3c2410-rtc alarm", info);
 566         if (ret) {
 567                 dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
 568                 goto err_nortc;
 569         }
 570
 571         ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
 572                           0,  "s3c2410-rtc tick", info);
 573         if (ret) {
 574                 dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
 575                 goto err_nortc;
 576         }
 577
 578         /* Check RTC Time */
 579         s3c_rtc_gettime(&pdev->dev, &rtc_tm);
 580
 581         if (rtc_valid_tm(&rtc_tm)) {
 582                 rtc_tm.tm_year  = 100;
 583                 rtc_tm.tm_mon   = 0;
 584                 rtc_tm.tm_mday  = 1;
 585                 rtc_tm.tm_hour  = 0;
 586                 rtc_tm.tm_min   = 0;
 587                 rtc_tm.tm_sec   = 0;
 588
 589                 s3c_rtc_settime(&pdev->dev, &rtc_tm);
 590
 591                 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
 592         }
 593
 594         if (info->data->select_tick_clk)
 595                 info->data->select_tick_clk(info);
 596
 597         s3c_rtc_setfreq(info, 1);
 598
 599         if (info->data->needs_src_clk)
 600                 clk_disable(info->rtc_src_clk);
 601         clk_disable(info->rtc_clk);
 602
 603         return 0;
 604
 605  err_nortc:
 606         if (info->data->disable)
 607                 info->data->disable(info);
 608         clk_disable_unprepare(info->rtc_clk);
 609
 610         return ret;
 611 }
 612
 613 #ifdef CONFIG_PM_SLEEP
 614
 615 static int s3c_rtc_suspend(struct device *dev)
 616 {
 617         struct s3c_rtc *info = dev_get_drvdata(dev);
 618
 619         clk_enable(info->rtc_clk);
 620         if (info->data->needs_src_clk)
 621                 clk_enable(info->rtc_src_clk);
 622
 623         /* save TICNT for anyone using periodic interrupts */
 624         if (info->data->save_tick_cnt)
 625                 info->data->save_tick_cnt(info);
 626
 627         if (info->data->disable)
 628                 info->data->disable(info);
 629
 630         if (device_may_wakeup(dev) && !info->wake_en) {
 631                 if (enable_irq_wake(info->irq_alarm) == 0)
 632                         info->wake_en = true;
 633                 else
 634                         dev_err(dev, "enable_irq_wake failed\n");
 635         }
 636
 637         if (info->data->needs_src_clk)
 638                 clk_disable(info->rtc_src_clk);
 639         clk_disable(info->rtc_clk);
 640
 641         return 0;
 642 }
 643
 644 static int s3c_rtc_resume(struct device *dev)
 645 {
 646         struct s3c_rtc *info = dev_get_drvdata(dev);
 647
 648         clk_enable(info->rtc_clk);
 649         if (info->data->needs_src_clk)
 650                 clk_enable(info->rtc_src_clk);
 651
 652         if (info->data->enable)
 653                 info->data->enable(info);
 654
 655         if (info->data->restore_tick_cnt)
 656                 info->data->restore_tick_cnt(info);
 657
 658         if (device_may_wakeup(dev) && info->wake_en) {
 659                 disable_irq_wake(info->irq_alarm);
 660                 info->wake_en = false;
 661         }
 662
 663         if (info->data->needs_src_clk)
 664                 clk_disable(info->rtc_src_clk);
 665         clk_disable(info->rtc_clk);
 666
 667         return 0;
 668 }
 669 #endif
 670 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
 671
 672 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
 673 {
 674         clk_enable(info->rtc_clk);
 675         if (info->data->needs_src_clk)
 676                 clk_enable(info->rtc_src_clk);
 677         rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
 678         if (info->data->needs_src_clk)
 679                 clk_disable(info->rtc_src_clk);
 680         clk_disable(info->rtc_clk);
 681
 682         s3c_rtc_alarm_clk_enable(info, false);
 683 }
 684
 685 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
 686 {
 687         clk_enable(info->rtc_clk);
 688         if (info->data->needs_src_clk)
 689                 clk_enable(info->rtc_src_clk);
 690         rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
 691         writeb(mask, info->base + S3C2410_INTP);
 692         if (info->data->needs_src_clk)
 693                 clk_disable(info->rtc_src_clk);
 694         clk_disable(info->rtc_clk);
 695
 696         s3c_rtc_alarm_clk_enable(info, false);
 697 }
 698
 699 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
 700 {
 701         unsigned int tmp = 0;
 702         int val;
 703
 704         tmp = readb(info->base + S3C2410_TICNT);
 705         tmp &= S3C2410_TICNT_ENABLE;
 706
 707         val = (info->rtc->max_user_freq / freq) - 1;
 708         tmp |= val;
 709
 710         writel(tmp, info->base + S3C2410_TICNT);
 711 }
 712
 713 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
 714 {
 715         unsigned int tmp = 0;
 716         int val;
 717
 718         tmp = readb(info->base + S3C2410_TICNT);
 719         tmp &= S3C2410_TICNT_ENABLE;
 720
 721         val = (info->rtc->max_user_freq / freq) - 1;
 722
 723         tmp |= S3C2443_TICNT_PART(val);
 724         writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
 725
 726         writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
 727
 728         writel(tmp, info->base + S3C2410_TICNT);
 729 }
 730
 731 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
 732 {
 733         unsigned int tmp = 0;
 734         int val;
 735
 736         tmp = readb(info->base + S3C2410_TICNT);
 737         tmp &= S3C2410_TICNT_ENABLE;
 738
 739         val = (info->rtc->max_user_freq / freq) - 1;
 740
 741         tmp |= S3C2443_TICNT_PART(val);
 742         writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
 743
 744         writel(tmp, info->base + S3C2410_TICNT);
 745 }
 746
 747 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
 748 {
 749         int val;
 750
 751         val = (info->rtc->max_user_freq / freq) - 1;
 752         writel(val, info->base + S3C2410_TICNT);
 753 }
 754
 755 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
 756 {
 757         unsigned int ticnt;
 758
 759         ticnt = readb(info->base + S3C2410_TICNT);
 760         ticnt &= S3C2410_TICNT_ENABLE;
 761
 762         seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
 763 }
 764
 765 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
 766 {
 767         unsigned int con;
 768
 769         con = readw(info->base + S3C2410_RTCCON);
 770         con |= S3C2443_RTCCON_TICSEL;
 771         writew(con, info->base + S3C2410_RTCCON);
 772 }
 773
 774 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
 775 {
 776         unsigned int ticnt;
 777
 778         ticnt = readw(info->base + S3C2410_RTCCON);
 779         ticnt &= S3C64XX_RTCCON_TICEN;
 780
 781         seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
 782 }
 783
 784 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
 785 {
 786         info->ticnt_save = readb(info->base + S3C2410_TICNT);
 787 }
 788
 789 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
 790 {
 791         writeb(info->ticnt_save, info->base + S3C2410_TICNT);
 792 }
 793
 794 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
 795 {
 796         info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
 797         info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
 798         info->ticnt_save = readl(info->base + S3C2410_TICNT);
 799 }
 800
 801 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
 802 {
 803         unsigned int con;
 804
 805         writel(info->ticnt_save, info->base + S3C2410_TICNT);
 806         if (info->ticnt_en_save) {
 807                 con = readw(info->base + S3C2410_RTCCON);
 808                 writew(con | info->ticnt_en_save,
 809                                 info->base + S3C2410_RTCCON);
 810         }
 811 }
 812
 813 static struct s3c_rtc_data const s3c2410_rtc_data = {
 814         .max_user_freq          = 128,
 815         .irq_handler            = s3c24xx_rtc_irq,
 816         .set_freq               = s3c2410_rtc_setfreq,
 817         .enable_tick            = s3c24xx_rtc_enable_tick,
 818         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 819         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 820         .enable                 = s3c24xx_rtc_enable,
 821         .disable                = s3c24xx_rtc_disable,
 822 };
 823
 824 static struct s3c_rtc_data const s3c2416_rtc_data = {
 825         .max_user_freq          = 32768,
 826         .irq_handler            = s3c24xx_rtc_irq,
 827         .set_freq               = s3c2416_rtc_setfreq,
 828         .enable_tick            = s3c24xx_rtc_enable_tick,
 829         .select_tick_clk        = s3c2416_rtc_select_tick_clk,
 830         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 831         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 832         .enable                 = s3c24xx_rtc_enable,
 833         .disable                = s3c24xx_rtc_disable,
 834 };
 835
 836 static struct s3c_rtc_data const s3c2443_rtc_data = {
 837         .max_user_freq          = 32768,
 838         .irq_handler            = s3c24xx_rtc_irq,
 839         .set_freq               = s3c2443_rtc_setfreq,
 840         .enable_tick            = s3c24xx_rtc_enable_tick,
 841         .select_tick_clk        = s3c2416_rtc_select_tick_clk,
 842         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 843         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 844         .enable                 = s3c24xx_rtc_enable,
 845         .disable                = s3c24xx_rtc_disable,
 846 };
 847
 848 static struct s3c_rtc_data const s3c6410_rtc_data = {
 849         .max_user_freq          = 32768,
 850         .irq_handler            = s3c6410_rtc_irq,
 851         .set_freq               = s3c6410_rtc_setfreq,
 852         .enable_tick            = s3c6410_rtc_enable_tick,
 853         .save_tick_cnt          = s3c6410_rtc_save_tick_cnt,
 854         .restore_tick_cnt       = s3c6410_rtc_restore_tick_cnt,
 855         .enable                 = s3c24xx_rtc_enable,
 856         .disable                = s3c6410_rtc_disable,
 857 };
 858
 859 static struct s3c_rtc_data const exynos3250_rtc_data = {
 860         .max_user_freq          = 32768,
 861         .needs_src_clk          = true,
 862         .irq_handler            = s3c6410_rtc_irq,
 863         .set_freq               = s3c6410_rtc_setfreq,
 864         .enable_tick            = s3c6410_rtc_enable_tick,
 865         .save_tick_cnt          = s3c6410_rtc_save_tick_cnt,
 866         .restore_tick_cnt       = s3c6410_rtc_restore_tick_cnt,
 867         .enable                 = s3c24xx_rtc_enable,
 868         .disable                = s3c6410_rtc_disable,
 869 };
 870
 871 static const struct of_device_id s3c_rtc_dt_match[] = {
 872         {
 873                 .compatible = "samsung,s3c2410-rtc",
 874                 .data = (void *)&s3c2410_rtc_data,
 875         }, {
 876                 .compatible = "samsung,s3c2416-rtc",
 877                 .data = (void *)&s3c2416_rtc_data,
 878         }, {
 879                 .compatible = "samsung,s3c2443-rtc",
 880                 .data = (void *)&s3c2443_rtc_data,
 881         }, {
 882                 .compatible = "samsung,s3c6410-rtc",
 883                 .data = (void *)&s3c6410_rtc_data,
 884         }, {
 885                 .compatible = "samsung,exynos3250-rtc",
 886                 .data = (void *)&exynos3250_rtc_data,
 887         },
 888         { /* sentinel */ },
 889 };
 890 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
 891
 892 static struct platform_driver s3c_rtc_driver = {
 893         .probe          = s3c_rtc_probe,
 894         .remove         = s3c_rtc_remove,
 895         .driver         = {
 896                 .name   = "s3c-rtc",
 897                 .owner  = THIS_MODULE,
 898                 .pm     = &s3c_rtc_pm_ops,
 899                 .of_match_table = of_match_ptr(s3c_rtc_dt_match),
 900         },
 901 };
 902 module_platform_driver(s3c_rtc_driver);
 903
 904 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
 905 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 906 MODULE_LICENSE("GPL");
 907 MODULE_ALIAS("platform:s3c2410-rtc");