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
  30 #include <mach/hardware.h>
  31 #include <asm/uaccess.h>
  32 #include <asm/io.h>
  33 #include <asm/irq.h>
  34 #include <plat/regs-rtc.h>
  35
  36 enum s3c_cpu_type {
  37         TYPE_S3C2410,
  38         TYPE_S3C64XX,
  39 };
  40
  41 /* I have yet to find an S3C implementation with more than one
  42  * of these rtc blocks in */
  43
  44 static struct resource *s3c_rtc_mem;
  45
  46 static struct clk *rtc_clk;
  47 static void __iomem *s3c_rtc_base;
  48 static int s3c_rtc_alarmno = NO_IRQ;
  49 static int s3c_rtc_tickno  = NO_IRQ;
  50 static bool wake_en;
  51 static enum s3c_cpu_type s3c_rtc_cpu_type;
  52
  53 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
  54
  55 static void s3c_rtc_alarm_clk_enable(bool enable)
  56 {
  57         static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock);
  58         static bool alarm_clk_enabled;
  59         unsigned long irq_flags;
  60
  61         spin_lock_irqsave(&s3c_rtc_alarm_clk_lock, irq_flags);
  62         if (enable) {
  63                 if (!alarm_clk_enabled) {
  64                         clk_enable(rtc_clk);
  65                         alarm_clk_enabled = true;
  66                 }
  67         } else {
  68                 if (alarm_clk_enabled) {
  69                         clk_disable(rtc_clk);
  70                         alarm_clk_enabled = false;
  71                 }
  72         }
  73         spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock, irq_flags);
  74 }
  75
  76 /* IRQ Handlers */
  77
  78 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
  79 {
  80         struct rtc_device *rdev = id;
  81
  82         clk_enable(rtc_clk);
  83         rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
  84
  85         if (s3c_rtc_cpu_type == TYPE_S3C64XX)
  86                 writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
  87
  88         clk_disable(rtc_clk);
  89
  90         s3c_rtc_alarm_clk_enable(false);
  91
  92         return IRQ_HANDLED;
  93 }
  94
  95 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
  96 {
  97         struct rtc_device *rdev = id;
  98
  99         clk_enable(rtc_clk);
 100         rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
 101
 102         if (s3c_rtc_cpu_type == TYPE_S3C64XX)
 103                 writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
 104
 105         clk_disable(rtc_clk);
 106         return IRQ_HANDLED;
 107 }
 108
 109 /* Update control registers */
 110 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
 111 {
 112         unsigned int tmp;
 113
 114         pr_debug("%s: aie=%d\n", __func__, enabled);
 115
 116         clk_enable(rtc_clk);
 117         tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
 118
 119         if (enabled)
 120                 tmp |= S3C2410_RTCALM_ALMEN;
 121
 122         writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
 123         clk_disable(rtc_clk);
 124
 125         s3c_rtc_alarm_clk_enable(enabled);
 126
 127         return 0;
 128 }
 129
 130 static int s3c_rtc_setfreq(struct device *dev, int freq)
 131 {
 132         struct platform_device *pdev = to_platform_device(dev);
 133         struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
 134         unsigned int tmp = 0;
 135
 136         if (!is_power_of_2(freq))
 137                 return -EINVAL;
 138
 139         clk_enable(rtc_clk);
 140         spin_lock_irq(&s3c_rtc_pie_lock);
 141
 142         if (s3c_rtc_cpu_type == TYPE_S3C2410) {
 143                 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
 144                 tmp &= S3C2410_TICNT_ENABLE;
 145         }
 146
 147         tmp |= (rtc_dev->max_user_freq / freq)-1;
 148
 149         writel(tmp, s3c_rtc_base + S3C2410_TICNT);
 150         spin_unlock_irq(&s3c_rtc_pie_lock);
 151         clk_disable(rtc_clk);
 152
 153         return 0;
 154 }
 155
 156 /* Time read/write */
 157
 158 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 159 {
 160         unsigned int have_retried = 0;
 161         void __iomem *base = s3c_rtc_base;
 162
 163         clk_enable(rtc_clk);
 164  retry_get_time:
 165         rtc_tm->tm_min  = readb(base + S3C2410_RTCMIN);
 166         rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
 167         rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
 168         rtc_tm->tm_mon  = readb(base + S3C2410_RTCMON);
 169         rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
 170         rtc_tm->tm_sec  = readb(base + S3C2410_RTCSEC);
 171
 172         /* the only way to work out wether the system was mid-update
 173          * when we read it is to check the second counter, and if it
 174          * is zero, then we re-try the entire read
 175          */
 176
 177         if (rtc_tm->tm_sec == 0 && !have_retried) {
 178                 have_retried = 1;
 179                 goto retry_get_time;
 180         }
 181
 182         rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
 183         rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
 184         rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
 185         rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
 186         rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
 187         rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
 188
 189         rtc_tm->tm_year += 100;
 190
 191         pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
 192                  1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
 193                  rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
 194
 195         rtc_tm->tm_mon -= 1;
 196
 197         clk_disable(rtc_clk);
 198         return rtc_valid_tm(rtc_tm);
 199 }
 200
 201 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
 202 {
 203         void __iomem *base = s3c_rtc_base;
 204         int year = tm->tm_year - 100;
 205
 206         pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
 207                  1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
 208                  tm->tm_hour, tm->tm_min, tm->tm_sec);
 209
 210         /* we get around y2k by simply not supporting it */
 211
 212         if (year < 0 || year >= 100) {
 213                 dev_err(dev, "rtc only supports 100 years\n");
 214                 return -EINVAL;
 215         }
 216
 217         clk_enable(rtc_clk);
 218         writeb(bin2bcd(tm->tm_sec),  base + S3C2410_RTCSEC);
 219         writeb(bin2bcd(tm->tm_min),  base + S3C2410_RTCMIN);
 220         writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR);
 221         writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
 222         writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
 223         writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
 224         clk_disable(rtc_clk);
 225
 226         return 0;
 227 }
 228
 229 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
 230 {
 231         struct rtc_time *alm_tm = &alrm->time;
 232         void __iomem *base = s3c_rtc_base;
 233         unsigned int alm_en;
 234
 235         clk_enable(rtc_clk);
 236         alm_tm->tm_sec  = readb(base + S3C2410_ALMSEC);
 237         alm_tm->tm_min  = readb(base + S3C2410_ALMMIN);
 238         alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
 239         alm_tm->tm_mon  = readb(base + S3C2410_ALMMON);
 240         alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
 241         alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
 242
 243         alm_en = readb(base + S3C2410_RTCALM);
 244
 245         alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
 246
 247         pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 248                  alm_en,
 249                  1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
 250                  alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
 251
 252
 253         /* decode the alarm enable field */
 254
 255         if (alm_en & S3C2410_RTCALM_SECEN)
 256                 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
 257         else
 258                 alm_tm->tm_sec = -1;
 259
 260         if (alm_en & S3C2410_RTCALM_MINEN)
 261                 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
 262         else
 263                 alm_tm->tm_min = -1;
 264
 265         if (alm_en & S3C2410_RTCALM_HOUREN)
 266                 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
 267         else
 268                 alm_tm->tm_hour = -1;
 269
 270         if (alm_en & S3C2410_RTCALM_DAYEN)
 271                 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
 272         else
 273                 alm_tm->tm_mday = -1;
 274
 275         if (alm_en & S3C2410_RTCALM_MONEN) {
 276                 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
 277                 alm_tm->tm_mon -= 1;
 278         } else {
 279                 alm_tm->tm_mon = -1;
 280         }
 281
 282         if (alm_en & S3C2410_RTCALM_YEAREN)
 283                 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
 284         else
 285                 alm_tm->tm_year = -1;
 286
 287         clk_disable(rtc_clk);
 288         return 0;
 289 }
 290
 291 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
 292 {
 293         struct rtc_time *tm = &alrm->time;
 294         void __iomem *base = s3c_rtc_base;
 295         unsigned int alrm_en;
 296
 297         clk_enable(rtc_clk);
 298         pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 299                  alrm->enabled,
 300                  1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
 301                  tm->tm_hour, tm->tm_min, tm->tm_sec);
 302
 303         alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
 304         writeb(0x00, base + S3C2410_RTCALM);
 305
 306         if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
 307                 alrm_en |= S3C2410_RTCALM_SECEN;
 308                 writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
 309         }
 310
 311         if (tm->tm_min < 60 && tm->tm_min >= 0) {
 312                 alrm_en |= S3C2410_RTCALM_MINEN;
 313                 writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
 314         }
 315
 316         if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
 317                 alrm_en |= S3C2410_RTCALM_HOUREN;
 318                 writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
 319         }
 320
 321         pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
 322
 323         writeb(alrm_en, base + S3C2410_RTCALM);
 324
 325         s3c_rtc_setaie(dev, alrm->enabled);
 326
 327         clk_disable(rtc_clk);
 328         return 0;
 329 }
 330
 331 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
 332 {
 333         unsigned int ticnt;
 334
 335         clk_enable(rtc_clk);
 336         if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
 337                 ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
 338                 ticnt &= S3C64XX_RTCCON_TICEN;
 339         } else {
 340                 ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
 341                 ticnt &= S3C2410_TICNT_ENABLE;
 342         }
 343
 344         seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
 345         clk_disable(rtc_clk);
 346         return 0;
 347 }
 348
 349 static const struct rtc_class_ops s3c_rtcops = {
 350         .read_time      = s3c_rtc_gettime,
 351         .set_time       = s3c_rtc_settime,
 352         .read_alarm     = s3c_rtc_getalarm,
 353         .set_alarm      = s3c_rtc_setalarm,
 354         .proc           = s3c_rtc_proc,
 355         .alarm_irq_enable = s3c_rtc_setaie,
 356 };
 357
 358 static void s3c_rtc_enable(struct platform_device *pdev, int en)
 359 {
 360         void __iomem *base = s3c_rtc_base;
 361         unsigned int tmp;
 362
 363         if (s3c_rtc_base == NULL)
 364                 return;
 365
 366         clk_enable(rtc_clk);
 367         if (!en) {
 368                 tmp = readw(base + S3C2410_RTCCON);
 369                 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
 370                         tmp &= ~S3C64XX_RTCCON_TICEN;
 371                 tmp &= ~S3C2410_RTCCON_RTCEN;
 372                 writew(tmp, base + S3C2410_RTCCON);
 373
 374                 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
 375                         tmp = readb(base + S3C2410_TICNT);
 376                         tmp &= ~S3C2410_TICNT_ENABLE;
 377                         writeb(tmp, base + S3C2410_TICNT);
 378                 }
 379         } else {
 380                 /* re-enable the device, and check it is ok */
 381
 382                 if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) {
 383                         dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
 384
 385                         tmp = readw(base + S3C2410_RTCCON);
 386                         writew(tmp | S3C2410_RTCCON_RTCEN,
 387                                 base + S3C2410_RTCCON);
 388                 }
 389
 390                 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) {
 391                         dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
 392
 393                         tmp = readw(base + S3C2410_RTCCON);
 394                         writew(tmp & ~S3C2410_RTCCON_CNTSEL,
 395                                 base + S3C2410_RTCCON);
 396                 }
 397
 398                 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) {
 399                         dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
 400
 401                         tmp = readw(base + S3C2410_RTCCON);
 402                         writew(tmp & ~S3C2410_RTCCON_CLKRST,
 403                                 base + S3C2410_RTCCON);
 404                 }
 405         }
 406         clk_disable(rtc_clk);
 407 }
 408
 409 static int __devexit s3c_rtc_remove(struct platform_device *dev)
 410 {
 411         struct rtc_device *rtc = platform_get_drvdata(dev);
 412
 413         free_irq(s3c_rtc_alarmno, rtc);
 414         free_irq(s3c_rtc_tickno, rtc);
 415
 416         platform_set_drvdata(dev, NULL);
 417         rtc_device_unregister(rtc);
 418
 419         s3c_rtc_setaie(&dev->dev, 0);
 420
 421         clk_put(rtc_clk);
 422         rtc_clk = NULL;
 423
 424         iounmap(s3c_rtc_base);
 425         release_resource(s3c_rtc_mem);
 426         kfree(s3c_rtc_mem);
 427
 428         return 0;
 429 }
 430
 431 static int __devinit s3c_rtc_probe(struct platform_device *pdev)
 432 {
 433         struct rtc_device *rtc;
 434         struct rtc_time rtc_tm;
 435         struct resource *res;
 436         int ret;
 437
 438         pr_debug("%s: probe=%p\n", __func__, pdev);
 439
 440         /* find the IRQs */
 441
 442         s3c_rtc_tickno = platform_get_irq(pdev, 1);
 443         if (s3c_rtc_tickno < 0) {
 444                 dev_err(&pdev->dev, "no irq for rtc tick\n");
 445                 return -ENOENT;
 446         }
 447
 448         s3c_rtc_alarmno = platform_get_irq(pdev, 0);
 449         if (s3c_rtc_alarmno < 0) {
 450                 dev_err(&pdev->dev, "no irq for alarm\n");
 451                 return -ENOENT;
 452         }
 453
 454         pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
 455                  s3c_rtc_tickno, s3c_rtc_alarmno);
 456
 457         /* get the memory region */
 458
 459         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 460         if (res == NULL) {
 461                 dev_err(&pdev->dev, "failed to get memory region resource\n");
 462                 return -ENOENT;
 463         }
 464
 465         s3c_rtc_mem = request_mem_region(res->start, resource_size(res),
 466                                          pdev->name);
 467
 468         if (s3c_rtc_mem == NULL) {
 469                 dev_err(&pdev->dev, "failed to reserve memory region\n");
 470                 ret = -ENOENT;
 471                 goto err_nores;
 472         }
 473
 474         s3c_rtc_base = ioremap(res->start, resource_size(res));
 475         if (s3c_rtc_base == NULL) {
 476                 dev_err(&pdev->dev, "failed ioremap()\n");
 477                 ret = -EINVAL;
 478                 goto err_nomap;
 479         }
 480
 481         rtc_clk = clk_get(&pdev->dev, "rtc");
 482         if (IS_ERR(rtc_clk)) {
 483                 dev_err(&pdev->dev, "failed to find rtc clock source\n");
 484                 ret = PTR_ERR(rtc_clk);
 485                 rtc_clk = NULL;
 486                 goto err_clk;
 487         }
 488
 489         clk_enable(rtc_clk);
 490
 491         /* check to see if everything is setup correctly */
 492
 493         s3c_rtc_enable(pdev, 1);
 494
 495         pr_debug("s3c2410_rtc: RTCCON=%02x\n",
 496                  readw(s3c_rtc_base + S3C2410_RTCCON));
 497
 498         device_init_wakeup(&pdev->dev, 1);
 499
 500         /* register RTC and exit */
 501
 502         rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
 503                                   THIS_MODULE);
 504
 505         if (IS_ERR(rtc)) {
 506                 dev_err(&pdev->dev, "cannot attach rtc\n");
 507                 ret = PTR_ERR(rtc);
 508                 goto err_nortc;
 509         }
 510
 511 #ifdef CONFIG_OF
 512         if (pdev->dev.of_node)
 513                 s3c_rtc_cpu_type = of_device_is_compatible(pdev->dev.of_node,
 514                         "samsung,s3c6410-rtc") ? TYPE_S3C64XX : TYPE_S3C2410;
 515         else
 516 #endif
 517                 s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;
 518
 519         /* Check RTC Time */
 520
 521         s3c_rtc_gettime(NULL, &rtc_tm);
 522
 523         if (rtc_valid_tm(&rtc_tm)) {
 524                 rtc_tm.tm_year  = 100;
 525                 rtc_tm.tm_mon   = 0;
 526                 rtc_tm.tm_mday  = 1;
 527                 rtc_tm.tm_hour  = 0;
 528                 rtc_tm.tm_min   = 0;
 529                 rtc_tm.tm_sec   = 0;
 530
 531                 s3c_rtc_settime(NULL, &rtc_tm);
 532
 533                 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
 534         }
 535
 536         if (s3c_rtc_cpu_type == TYPE_S3C64XX)
 537                 rtc->max_user_freq = 32768;
 538         else
 539                 rtc->max_user_freq = 128;
 540
 541         platform_set_drvdata(pdev, rtc);
 542
 543         s3c_rtc_setfreq(&pdev->dev, 1);
 544
 545         ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
 546                           0,  "s3c2410-rtc alarm", rtc);
 547         if (ret) {
 548                 dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
 549                 goto err_alarm_irq;
 550         }
 551
 552         ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
 553                           0,  "s3c2410-rtc tick", rtc);
 554         if (ret) {
 555                 dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
 556                 free_irq(s3c_rtc_alarmno, rtc);
 557                 goto err_tick_irq;
 558         }
 559
 560         clk_disable(rtc_clk);
 561
 562         return 0;
 563
 564  err_tick_irq:
 565         free_irq(s3c_rtc_alarmno, rtc);
 566
 567  err_alarm_irq:
 568         platform_set_drvdata(pdev, NULL);
 569         rtc_device_unregister(rtc);
 570
 571  err_nortc:
 572         s3c_rtc_enable(pdev, 0);
 573         clk_disable(rtc_clk);
 574         clk_put(rtc_clk);
 575
 576  err_clk:
 577         iounmap(s3c_rtc_base);
 578
 579  err_nomap:
 580         release_resource(s3c_rtc_mem);
 581
 582  err_nores:
 583         return ret;
 584 }
 585
 586 #ifdef CONFIG_PM
 587
 588 /* RTC Power management control */
 589
 590 static int ticnt_save, ticnt_en_save;
 591
 592 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
 593 {
 594         clk_enable(rtc_clk);
 595         /* save TICNT for anyone using periodic interrupts */
 596         ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
 597         if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
 598                 ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
 599                 ticnt_en_save &= S3C64XX_RTCCON_TICEN;
 600         }
 601         s3c_rtc_enable(pdev, 0);
 602
 603         if (device_may_wakeup(&pdev->dev) && !wake_en) {
 604                 if (enable_irq_wake(s3c_rtc_alarmno) == 0)
 605                         wake_en = true;
 606                 else
 607                         dev_err(&pdev->dev, "enable_irq_wake failed\n");
 608         }
 609         clk_disable(rtc_clk);
 610
 611         return 0;
 612 }
 613
 614 static int s3c_rtc_resume(struct platform_device *pdev)
 615 {
 616         unsigned int tmp;
 617
 618         clk_enable(rtc_clk);
 619         s3c_rtc_enable(pdev, 1);
 620         writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
 621         if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
 622                 tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
 623                 writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
 624         }
 625
 626         if (device_may_wakeup(&pdev->dev) && wake_en) {
 627                 disable_irq_wake(s3c_rtc_alarmno);
 628                 wake_en = false;
 629         }
 630         clk_disable(rtc_clk);
 631
 632         return 0;
 633 }
 634 #else
 635 #define s3c_rtc_suspend NULL
 636 #define s3c_rtc_resume  NULL
 637 #endif
 638
 639 #ifdef CONFIG_OF
 640 static const struct of_device_id s3c_rtc_dt_match[] = {
 641         { .compatible = "samsung,s3c2410-rtc" },
 642         { .compatible = "samsung,s3c6410-rtc" },
 643         {},
 644 };
 645 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
 646 #else
 647 #define s3c_rtc_dt_match NULL
 648 #endif
 649
 650 static struct platform_device_id s3c_rtc_driver_ids[] = {
 651         {
 652                 .name           = "s3c2410-rtc",
 653                 .driver_data    = TYPE_S3C2410,
 654         }, {
 655                 .name           = "s3c64xx-rtc",
 656                 .driver_data    = TYPE_S3C64XX,
 657         },
 658         { }
 659 };
 660
 661 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
 662
 663 static struct platform_driver s3c_rtc_driver = {
 664         .probe          = s3c_rtc_probe,
 665         .remove         = __devexit_p(s3c_rtc_remove),
 666         .suspend        = s3c_rtc_suspend,
 667         .resume         = s3c_rtc_resume,
 668         .id_table       = s3c_rtc_driver_ids,
 669         .driver         = {
 670                 .name   = "s3c-rtc",
 671                 .owner  = THIS_MODULE,
 672                 .of_match_table = s3c_rtc_dt_match,
 673         },
 674 };
 675
 676 module_platform_driver(s3c_rtc_driver);
 677
 678 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
 679 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 680 MODULE_LICENSE("GPL");
 681 MODULE_ALIAS("platform:s3c2410-rtc");