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 clk_disabled;
  43
  44         const 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;
  53         int ticnt_en_save;
  54         bool wake_en;
  55 };
  56
  57 struct s3c_rtc_data {
  58         int max_user_freq;
  59         bool needs_src_clk;
  60
  61         void (*irq_handler) (struct s3c_rtc *info, int mask);
  62         void (*set_freq) (struct s3c_rtc *info, int freq);
  63         void (*enable_tick) (struct s3c_rtc *info, struct seq_file *seq);
  64         void (*select_tick_clk) (struct s3c_rtc *info);
  65         void (*save_tick_cnt) (struct s3c_rtc *info);
  66         void (*restore_tick_cnt) (struct s3c_rtc *info);
  67         void (*enable) (struct s3c_rtc *info);
  68         void (*disable) (struct s3c_rtc *info);
  69 };
  70
  71 static int s3c_rtc_enable_clk(struct s3c_rtc *info)
  72 {
  73         unsigned long irq_flags;
  74         int ret = 0;
  75
  76         spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
  77
  78         if (info->clk_disabled) {
  79                 ret = clk_enable(info->rtc_clk);
  80                 if (ret)
  81                         goto out;
  82
  83                 if (info->data->needs_src_clk) {
  84                         ret = clk_enable(info->rtc_src_clk);
  85                         if (ret) {
  86                                 clk_disable(info->rtc_clk);
  87                                 goto out;
  88                         }
  89                 }
  90                 info->clk_disabled = false;
  91         }
  92
  93 out:
  94         spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
  95
  96         return ret;
  97 }
  98
  99 static void s3c_rtc_disable_clk(struct s3c_rtc *info)
 100 {
 101         unsigned long irq_flags;
 102
 103         spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
 104         if (!info->clk_disabled) {
 105                 if (info->data->needs_src_clk)
 106                         clk_disable(info->rtc_src_clk);
 107                 clk_disable(info->rtc_clk);
 108                 info->clk_disabled = true;
 109         }
 110         spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
 111 }
 112
 113 /* IRQ Handlers */
 114 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
 115 {
 116         struct s3c_rtc *info = (struct s3c_rtc *)id;
 117
 118         if (info->data->irq_handler)
 119                 info->data->irq_handler(info, S3C2410_INTP_TIC);
 120
 121         return IRQ_HANDLED;
 122 }
 123
 124 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
 125 {
 126         struct s3c_rtc *info = (struct s3c_rtc *)id;
 127
 128         if (info->data->irq_handler)
 129                 info->data->irq_handler(info, S3C2410_INTP_ALM);
 130
 131         return IRQ_HANDLED;
 132 }
 133
 134 /* Update control registers */
 135 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
 136 {
 137         struct s3c_rtc *info = dev_get_drvdata(dev);
 138         unsigned int tmp;
 139         int ret;
 140
 141         dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
 142
 143         ret = s3c_rtc_enable_clk(info);
 144         if (ret)
 145                 return ret;
 146
 147         tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
 148
 149         if (enabled)
 150                 tmp |= S3C2410_RTCALM_ALMEN;
 151
 152         writeb(tmp, info->base + S3C2410_RTCALM);
 153
 154         s3c_rtc_disable_clk(info);
 155
 156         if (enabled) {
 157                 ret = s3c_rtc_enable_clk(info);
 158                 if (ret)
 159                         return ret;
 160         } else {
 161                 s3c_rtc_disable_clk(info);
 162         }
 163
 164         return 0;
 165 }
 166
 167 /* Set RTC frequency */
 168 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
 169 {
 170         int ret;
 171
 172         if (!is_power_of_2(freq))
 173                 return -EINVAL;
 174
 175         ret = s3c_rtc_enable_clk(info);
 176         if (ret)
 177                 return ret;
 178         spin_lock_irq(&info->pie_lock);
 179
 180         if (info->data->set_freq)
 181                 info->data->set_freq(info, freq);
 182
 183         spin_unlock_irq(&info->pie_lock);
 184         s3c_rtc_disable_clk(info);
 185
 186         return 0;
 187 }
 188
 189 /* Time read/write */
 190 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 191 {
 192         struct s3c_rtc *info = dev_get_drvdata(dev);
 193         unsigned int have_retried = 0;
 194         int ret;
 195
 196         ret = s3c_rtc_enable_clk(info);
 197         if (ret)
 198                 return ret;
 199
 200 retry_get_time:
 201         rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
 202         rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
 203         rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
 204         rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
 205         rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
 206         rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
 207
 208         /* the only way to work out whether the system was mid-update
 209          * when we read it is to check the second counter, and if it
 210          * is zero, then we re-try the entire read
 211          */
 212
 213         if (rtc_tm->tm_sec == 0 && !have_retried) {
 214                 have_retried = 1;
 215                 goto retry_get_time;
 216         }
 217
 218         rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
 219         rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
 220         rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
 221         rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
 222         rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
 223         rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
 224
 225         s3c_rtc_disable_clk(info);
 226
 227         rtc_tm->tm_year += 100;
 228
 229         dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n",
 230                 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
 231                 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
 232
 233         rtc_tm->tm_mon -= 1;
 234
 235         return 0;
 236 }
 237
 238 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
 239 {
 240         struct s3c_rtc *info = dev_get_drvdata(dev);
 241         int year = tm->tm_year - 100;
 242         int ret;
 243
 244         dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n",
 245                 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
 246                 tm->tm_hour, tm->tm_min, tm->tm_sec);
 247
 248         /* we get around y2k by simply not supporting it */
 249
 250         if (year < 0 || year >= 100) {
 251                 dev_err(dev, "rtc only supports 100 years\n");
 252                 return -EINVAL;
 253         }
 254
 255         ret = s3c_rtc_enable_clk(info);
 256         if (ret)
 257                 return ret;
 258
 259         writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
 260         writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
 261         writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
 262         writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
 263         writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
 264         writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
 265
 266         s3c_rtc_disable_clk(info);
 267
 268         return 0;
 269 }
 270
 271 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
 272 {
 273         struct s3c_rtc *info = dev_get_drvdata(dev);
 274         struct rtc_time *alm_tm = &alrm->time;
 275         unsigned int alm_en;
 276         int ret;
 277
 278         ret = s3c_rtc_enable_clk(info);
 279         if (ret)
 280                 return ret;
 281
 282         alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
 283         alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
 284         alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
 285         alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
 286         alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
 287         alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
 288
 289         alm_en = readb(info->base + S3C2410_RTCALM);
 290
 291         s3c_rtc_disable_clk(info);
 292
 293         alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
 294
 295         dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 296                 alm_en,
 297                 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
 298                 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
 299
 300         /* decode the alarm enable field */
 301         if (alm_en & S3C2410_RTCALM_SECEN)
 302                 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
 303
 304         if (alm_en & S3C2410_RTCALM_MINEN)
 305                 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
 306
 307         if (alm_en & S3C2410_RTCALM_HOUREN)
 308                 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
 309
 310         if (alm_en & S3C2410_RTCALM_DAYEN)
 311                 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
 312
 313         if (alm_en & S3C2410_RTCALM_MONEN) {
 314                 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
 315                 alm_tm->tm_mon -= 1;
 316         }
 317
 318         if (alm_en & S3C2410_RTCALM_YEAREN)
 319                 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
 320
 321         return 0;
 322 }
 323
 324 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
 325 {
 326         struct s3c_rtc *info = dev_get_drvdata(dev);
 327         struct rtc_time *tm = &alrm->time;
 328         unsigned int alrm_en;
 329         int ret;
 330
 331         dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 332                 alrm->enabled,
 333                 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
 334                 tm->tm_hour, tm->tm_min, tm->tm_sec);
 335
 336         ret = s3c_rtc_enable_clk(info);
 337         if (ret)
 338                 return ret;
 339
 340         alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
 341         writeb(0x00, info->base + S3C2410_RTCALM);
 342
 343         if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
 344                 alrm_en |= S3C2410_RTCALM_SECEN;
 345                 writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
 346         }
 347
 348         if (tm->tm_min < 60 && tm->tm_min >= 0) {
 349                 alrm_en |= S3C2410_RTCALM_MINEN;
 350                 writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
 351         }
 352
 353         if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
 354                 alrm_en |= S3C2410_RTCALM_HOUREN;
 355                 writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
 356         }
 357
 358         if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
 359                 alrm_en |= S3C2410_RTCALM_MONEN;
 360                 writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
 361         }
 362
 363         if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
 364                 alrm_en |= S3C2410_RTCALM_DAYEN;
 365                 writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
 366         }
 367
 368         dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
 369
 370         writeb(alrm_en, info->base + S3C2410_RTCALM);
 371
 372         s3c_rtc_disable_clk(info);
 373
 374         s3c_rtc_setaie(dev, alrm->enabled);
 375
 376         return 0;
 377 }
 378
 379 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
 380 {
 381         struct s3c_rtc *info = dev_get_drvdata(dev);
 382         int ret;
 383
 384         ret = s3c_rtc_enable_clk(info);
 385         if (ret)
 386                 return ret;
 387
 388         if (info->data->enable_tick)
 389                 info->data->enable_tick(info, seq);
 390
 391         s3c_rtc_disable_clk(info);
 392
 393         return 0;
 394 }
 395
 396 static const struct rtc_class_ops s3c_rtcops = {
 397         .read_time      = s3c_rtc_gettime,
 398         .set_time       = s3c_rtc_settime,
 399         .read_alarm     = s3c_rtc_getalarm,
 400         .set_alarm      = s3c_rtc_setalarm,
 401         .proc           = s3c_rtc_proc,
 402         .alarm_irq_enable = s3c_rtc_setaie,
 403 };
 404
 405 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
 406 {
 407         unsigned int con, tmp;
 408
 409         con = readw(info->base + S3C2410_RTCCON);
 410         /* re-enable the device, and check it is ok */
 411         if ((con & S3C2410_RTCCON_RTCEN) == 0) {
 412                 dev_info(info->dev, "rtc disabled, re-enabling\n");
 413
 414                 tmp = readw(info->base + S3C2410_RTCCON);
 415                 writew(tmp | S3C2410_RTCCON_RTCEN, info->base + S3C2410_RTCCON);
 416         }
 417
 418         if (con & S3C2410_RTCCON_CNTSEL) {
 419                 dev_info(info->dev, "removing RTCCON_CNTSEL\n");
 420
 421                 tmp = readw(info->base + S3C2410_RTCCON);
 422                 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
 423                        info->base + S3C2410_RTCCON);
 424         }
 425
 426         if (con & S3C2410_RTCCON_CLKRST) {
 427                 dev_info(info->dev, "removing RTCCON_CLKRST\n");
 428
 429                 tmp = readw(info->base + S3C2410_RTCCON);
 430                 writew(tmp & ~S3C2410_RTCCON_CLKRST,
 431                        info->base + S3C2410_RTCCON);
 432         }
 433 }
 434
 435 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
 436 {
 437         unsigned int con;
 438
 439         con = readw(info->base + S3C2410_RTCCON);
 440         con &= ~S3C2410_RTCCON_RTCEN;
 441         writew(con, info->base + S3C2410_RTCCON);
 442
 443         con = readb(info->base + S3C2410_TICNT);
 444         con &= ~S3C2410_TICNT_ENABLE;
 445         writeb(con, info->base + S3C2410_TICNT);
 446 }
 447
 448 static void s3c6410_rtc_disable(struct s3c_rtc *info)
 449 {
 450         unsigned int con;
 451
 452         con = readw(info->base + S3C2410_RTCCON);
 453         con &= ~S3C64XX_RTCCON_TICEN;
 454         con &= ~S3C2410_RTCCON_RTCEN;
 455         writew(con, info->base + S3C2410_RTCCON);
 456 }
 457
 458 static int s3c_rtc_remove(struct platform_device *pdev)
 459 {
 460         struct s3c_rtc *info = platform_get_drvdata(pdev);
 461
 462         s3c_rtc_setaie(info->dev, 0);
 463
 464         if (info->data->needs_src_clk)
 465                 clk_unprepare(info->rtc_src_clk);
 466         clk_unprepare(info->rtc_clk);
 467
 468         return 0;
 469 }
 470
 471 static const struct of_device_id s3c_rtc_dt_match[];
 472
 473 static const struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
 474 {
 475         const struct of_device_id *match;
 476
 477         match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
 478         return match->data;
 479 }
 480
 481 static int s3c_rtc_probe(struct platform_device *pdev)
 482 {
 483         struct s3c_rtc *info = NULL;
 484         struct rtc_time rtc_tm;
 485         struct resource *res;
 486         int ret;
 487
 488         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 489         if (!info)
 490                 return -ENOMEM;
 491
 492         /* find the IRQs */
 493         info->irq_tick = platform_get_irq(pdev, 1);
 494         if (info->irq_tick < 0) {
 495                 dev_err(&pdev->dev, "no irq for rtc tick\n");
 496                 return info->irq_tick;
 497         }
 498
 499         info->dev = &pdev->dev;
 500         info->data = s3c_rtc_get_data(pdev);
 501         if (!info->data) {
 502                 dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
 503                 return -EINVAL;
 504         }
 505         spin_lock_init(&info->pie_lock);
 506         spin_lock_init(&info->alarm_clk_lock);
 507
 508         platform_set_drvdata(pdev, info);
 509
 510         info->irq_alarm = platform_get_irq(pdev, 0);
 511         if (info->irq_alarm < 0) {
 512                 dev_err(&pdev->dev, "no irq for alarm\n");
 513                 return info->irq_alarm;
 514         }
 515
 516         dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
 517                 info->irq_tick, info->irq_alarm);
 518
 519         /* get the memory region */
 520         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 521         info->base = devm_ioremap_resource(&pdev->dev, res);
 522         if (IS_ERR(info->base))
 523                 return PTR_ERR(info->base);
 524
 525         info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
 526         if (IS_ERR(info->rtc_clk)) {
 527                 ret = PTR_ERR(info->rtc_clk);
 528                 if (ret != -EPROBE_DEFER)
 529                         dev_err(&pdev->dev, "failed to find rtc clock\n");
 530                 else
 531                         dev_dbg(&pdev->dev, "probe deferred due to missing rtc clk\n");
 532                 return ret;
 533         }
 534         ret = clk_prepare_enable(info->rtc_clk);
 535         if (ret)
 536                 return ret;
 537
 538         if (info->data->needs_src_clk) {
 539                 info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
 540                 if (IS_ERR(info->rtc_src_clk)) {
 541                         ret = PTR_ERR(info->rtc_src_clk);
 542                         if (ret != -EPROBE_DEFER)
 543                                 dev_err(&pdev->dev,
 544                                         "failed to find rtc source clock\n");
 545                         else
 546                                 dev_dbg(&pdev->dev,
 547                                         "probe deferred due to missing rtc src clk\n");
 548                         goto err_src_clk;
 549                 }
 550                 ret = clk_prepare_enable(info->rtc_src_clk);
 551                 if (ret)
 552                         goto err_src_clk;
 553         }
 554
 555         /* check to see if everything is setup correctly */
 556         if (info->data->enable)
 557                 info->data->enable(info);
 558
 559         dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
 560                 readw(info->base + S3C2410_RTCCON));
 561
 562         device_init_wakeup(&pdev->dev, 1);
 563
 564         /* Check RTC Time */
 565         if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
 566                 rtc_tm.tm_year  = 100;
 567                 rtc_tm.tm_mon   = 0;
 568                 rtc_tm.tm_mday  = 1;
 569                 rtc_tm.tm_hour  = 0;
 570                 rtc_tm.tm_min   = 0;
 571                 rtc_tm.tm_sec   = 0;
 572
 573                 s3c_rtc_settime(&pdev->dev, &rtc_tm);
 574
 575                 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
 576         }
 577
 578         /* register RTC and exit */
 579         info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
 580                                              THIS_MODULE);
 581         if (IS_ERR(info->rtc)) {
 582                 dev_err(&pdev->dev, "cannot attach rtc\n");
 583                 ret = PTR_ERR(info->rtc);
 584                 goto err_nortc;
 585         }
 586
 587         ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
 588                                0, "s3c2410-rtc alarm", info);
 589         if (ret) {
 590                 dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
 591                 goto err_nortc;
 592         }
 593
 594         ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
 595                                0, "s3c2410-rtc tick", info);
 596         if (ret) {
 597                 dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
 598                 goto err_nortc;
 599         }
 600
 601         if (info->data->select_tick_clk)
 602                 info->data->select_tick_clk(info);
 603
 604         s3c_rtc_setfreq(info, 1);
 605
 606         return 0;
 607
 608 err_nortc:
 609         if (info->data->disable)
 610                 info->data->disable(info);
 611
 612         if (info->data->needs_src_clk)
 613                 clk_disable_unprepare(info->rtc_src_clk);
 614 err_src_clk:
 615         clk_disable_unprepare(info->rtc_clk);
 616
 617         return ret;
 618 }
 619
 620 #ifdef CONFIG_PM_SLEEP
 621
 622 static int s3c_rtc_suspend(struct device *dev)
 623 {
 624         struct s3c_rtc *info = dev_get_drvdata(dev);
 625         int ret;
 626
 627         ret = s3c_rtc_enable_clk(info);
 628         if (ret)
 629                 return ret;
 630
 631         /* save TICNT for anyone using periodic interrupts */
 632         if (info->data->save_tick_cnt)
 633                 info->data->save_tick_cnt(info);
 634
 635         if (info->data->disable)
 636                 info->data->disable(info);
 637
 638         if (device_may_wakeup(dev) && !info->wake_en) {
 639                 if (enable_irq_wake(info->irq_alarm) == 0)
 640                         info->wake_en = true;
 641                 else
 642                         dev_err(dev, "enable_irq_wake failed\n");
 643         }
 644
 645         return 0;
 646 }
 647
 648 static int s3c_rtc_resume(struct device *dev)
 649 {
 650         struct s3c_rtc *info = dev_get_drvdata(dev);
 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         s3c_rtc_disable_clk(info);
 659
 660         if (device_may_wakeup(dev) && info->wake_en) {
 661                 disable_irq_wake(info->irq_alarm);
 662                 info->wake_en = false;
 663         }
 664
 665         return 0;
 666 }
 667 #endif
 668 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
 669
 670 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
 671 {
 672         rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
 673 }
 674
 675 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
 676 {
 677         rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
 678         writeb(mask, info->base + S3C2410_INTP);
 679 }
 680
 681 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
 682 {
 683         unsigned int tmp = 0;
 684         int val;
 685
 686         tmp = readb(info->base + S3C2410_TICNT);
 687         tmp &= S3C2410_TICNT_ENABLE;
 688
 689         val = (info->rtc->max_user_freq / freq) - 1;
 690         tmp |= val;
 691
 692         writel(tmp, info->base + S3C2410_TICNT);
 693 }
 694
 695 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
 696 {
 697         unsigned int tmp = 0;
 698         int val;
 699
 700         tmp = readb(info->base + S3C2410_TICNT);
 701         tmp &= S3C2410_TICNT_ENABLE;
 702
 703         val = (info->rtc->max_user_freq / freq) - 1;
 704
 705         tmp |= S3C2443_TICNT_PART(val);
 706         writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
 707
 708         writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
 709
 710         writel(tmp, info->base + S3C2410_TICNT);
 711 }
 712
 713 static void s3c2443_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(tmp, info->base + S3C2410_TICNT);
 727 }
 728
 729 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
 730 {
 731         int val;
 732
 733         val = (info->rtc->max_user_freq / freq) - 1;
 734         writel(val, info->base + S3C2410_TICNT);
 735 }
 736
 737 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
 738 {
 739         unsigned int ticnt;
 740
 741         ticnt = readb(info->base + S3C2410_TICNT);
 742         ticnt &= S3C2410_TICNT_ENABLE;
 743
 744         seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
 745 }
 746
 747 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
 748 {
 749         unsigned int con;
 750
 751         con = readw(info->base + S3C2410_RTCCON);
 752         con |= S3C2443_RTCCON_TICSEL;
 753         writew(con, info->base + S3C2410_RTCCON);
 754 }
 755
 756 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
 757 {
 758         unsigned int ticnt;
 759
 760         ticnt = readw(info->base + S3C2410_RTCCON);
 761         ticnt &= S3C64XX_RTCCON_TICEN;
 762
 763         seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
 764 }
 765
 766 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
 767 {
 768         info->ticnt_save = readb(info->base + S3C2410_TICNT);
 769 }
 770
 771 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
 772 {
 773         writeb(info->ticnt_save, info->base + S3C2410_TICNT);
 774 }
 775
 776 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
 777 {
 778         info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
 779         info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
 780         info->ticnt_save = readl(info->base + S3C2410_TICNT);
 781 }
 782
 783 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
 784 {
 785         unsigned int con;
 786
 787         writel(info->ticnt_save, info->base + S3C2410_TICNT);
 788         if (info->ticnt_en_save) {
 789                 con = readw(info->base + S3C2410_RTCCON);
 790                 writew(con | info->ticnt_en_save, info->base + S3C2410_RTCCON);
 791         }
 792 }
 793
 794 static struct s3c_rtc_data const s3c2410_rtc_data = {
 795         .max_user_freq          = 128,
 796         .irq_handler            = s3c24xx_rtc_irq,
 797         .set_freq               = s3c2410_rtc_setfreq,
 798         .enable_tick            = s3c24xx_rtc_enable_tick,
 799         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 800         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 801         .enable                 = s3c24xx_rtc_enable,
 802         .disable                = s3c24xx_rtc_disable,
 803 };
 804
 805 static struct s3c_rtc_data const s3c2416_rtc_data = {
 806         .max_user_freq          = 32768,
 807         .irq_handler            = s3c24xx_rtc_irq,
 808         .set_freq               = s3c2416_rtc_setfreq,
 809         .enable_tick            = s3c24xx_rtc_enable_tick,
 810         .select_tick_clk        = s3c2416_rtc_select_tick_clk,
 811         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 812         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 813         .enable                 = s3c24xx_rtc_enable,
 814         .disable                = s3c24xx_rtc_disable,
 815 };
 816
 817 static struct s3c_rtc_data const s3c2443_rtc_data = {
 818         .max_user_freq          = 32768,
 819         .irq_handler            = s3c24xx_rtc_irq,
 820         .set_freq               = s3c2443_rtc_setfreq,
 821         .enable_tick            = s3c24xx_rtc_enable_tick,
 822         .select_tick_clk        = s3c2416_rtc_select_tick_clk,
 823         .save_tick_cnt          = s3c24xx_rtc_save_tick_cnt,
 824         .restore_tick_cnt       = s3c24xx_rtc_restore_tick_cnt,
 825         .enable                 = s3c24xx_rtc_enable,
 826         .disable                = s3c24xx_rtc_disable,
 827 };
 828
 829 static struct s3c_rtc_data const s3c6410_rtc_data = {
 830         .max_user_freq          = 32768,
 831         .needs_src_clk          = true,
 832         .irq_handler            = s3c6410_rtc_irq,
 833         .set_freq               = s3c6410_rtc_setfreq,
 834         .enable_tick            = s3c6410_rtc_enable_tick,
 835         .save_tick_cnt          = s3c6410_rtc_save_tick_cnt,
 836         .restore_tick_cnt       = s3c6410_rtc_restore_tick_cnt,
 837         .enable                 = s3c24xx_rtc_enable,
 838         .disable                = s3c6410_rtc_disable,
 839 };
 840
 841 static const struct of_device_id s3c_rtc_dt_match[] = {
 842         {
 843                 .compatible = "samsung,s3c2410-rtc",
 844                 .data = &s3c2410_rtc_data,
 845         }, {
 846                 .compatible = "samsung,s3c2416-rtc",
 847                 .data = &s3c2416_rtc_data,
 848         }, {
 849                 .compatible = "samsung,s3c2443-rtc",
 850                 .data = &s3c2443_rtc_data,
 851         }, {
 852                 .compatible = "samsung,s3c6410-rtc",
 853                 .data = &s3c6410_rtc_data,
 854         }, {
 855                 .compatible = "samsung,exynos3250-rtc",
 856                 .data = &s3c6410_rtc_data,
 857         },
 858         { /* sentinel */ },
 859 };
 860 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
 861
 862 static struct platform_driver s3c_rtc_driver = {
 863         .probe          = s3c_rtc_probe,
 864         .remove         = s3c_rtc_remove,
 865         .driver         = {
 866                 .name   = "s3c-rtc",
 867                 .pm     = &s3c_rtc_pm_ops,
 868                 .of_match_table = of_match_ptr(s3c_rtc_dt_match),
 869         },
 870 };
 871 module_platform_driver(s3c_rtc_driver);
 872
 873 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
 874 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 875 MODULE_LICENSE("GPL");
 876 MODULE_ALIAS("platform:s3c2410-rtc");