drivers/rtc/rtc-sh.c

   1 /*
   2  * SuperH On-Chip RTC Support
   3  *
   4  * Copyright (C) 2006 - 2009  Paul Mundt
   5  * Copyright (C) 2006  Jamie Lenehan
   6  * Copyright (C) 2008  Angelo Castello
   7  *
   8  * Based on the old arch/sh/kernel/cpu/rtc.c by:
   9  *
  10  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
  11  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
  12  *
  13  * This file is subject to the terms and conditions of the GNU General Public
  14  * License.  See the file "COPYING" in the main directory of this archive
  15  * for more details.
  16  */
  17 #include <linux/module.h>
  18 #include <linux/kernel.h>
  19 #include <linux/bcd.h>
  20 #include <linux/rtc.h>
  21 #include <linux/init.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/seq_file.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/io.h>
  27 #include <linux/log2.h>
  28 #include <linux/clk.h>
  29 #include <linux/slab.h>
  30 #include <asm/rtc.h>
  31
  32 #define DRV_NAME        "sh-rtc"
  33
  34 #define RTC_REG(r)      ((r) * rtc_reg_size)
  35
  36 #define R64CNT          RTC_REG(0)
  37
  38 #define RSECCNT         RTC_REG(1)      /* RTC sec */
  39 #define RMINCNT         RTC_REG(2)      /* RTC min */
  40 #define RHRCNT          RTC_REG(3)      /* RTC hour */
  41 #define RWKCNT          RTC_REG(4)      /* RTC week */
  42 #define RDAYCNT         RTC_REG(5)      /* RTC day */
  43 #define RMONCNT         RTC_REG(6)      /* RTC month */
  44 #define RYRCNT          RTC_REG(7)      /* RTC year */
  45 #define RSECAR          RTC_REG(8)      /* ALARM sec */
  46 #define RMINAR          RTC_REG(9)      /* ALARM min */
  47 #define RHRAR           RTC_REG(10)     /* ALARM hour */
  48 #define RWKAR           RTC_REG(11)     /* ALARM week */
  49 #define RDAYAR          RTC_REG(12)     /* ALARM day */
  50 #define RMONAR          RTC_REG(13)     /* ALARM month */
  51 #define RCR1            RTC_REG(14)     /* Control */
  52 #define RCR2            RTC_REG(15)     /* Control */
  53
  54 /*
  55  * Note on RYRAR and RCR3: Up until this point most of the register
  56  * definitions are consistent across all of the available parts. However,
  57  * the placement of the optional RYRAR and RCR3 (the RYRAR control
  58  * register used to control RYRCNT/RYRAR compare) varies considerably
  59  * across various parts, occasionally being mapped in to a completely
  60  * unrelated address space. For proper RYRAR support a separate resource
  61  * would have to be handed off, but as this is purely optional in
  62  * practice, we simply opt not to support it, thereby keeping the code
  63  * quite a bit more simplified.
  64  */
  65
  66 /* ALARM Bits - or with BCD encoded value */
  67 #define AR_ENB          0x80    /* Enable for alarm cmp   */
  68
  69 /* Period Bits */
  70 #define PF_HP           0x100   /* Enable Half Period to support 8,32,128Hz */
  71 #define PF_COUNT        0x200   /* Half periodic counter */
  72 #define PF_OXS          0x400   /* Periodic One x Second */
  73 #define PF_KOU          0x800   /* Kernel or User periodic request 1=kernel */
  74 #define PF_MASK         0xf00
  75
  76 /* RCR1 Bits */
  77 #define RCR1_CF         0x80    /* Carry Flag             */
  78 #define RCR1_CIE        0x10    /* Carry Interrupt Enable */
  79 #define RCR1_AIE        0x08    /* Alarm Interrupt Enable */
  80 #define RCR1_AF         0x01    /* Alarm Flag             */
  81
  82 /* RCR2 Bits */
  83 #define RCR2_PEF        0x80    /* PEriodic interrupt Flag */
  84 #define RCR2_PESMASK    0x70    /* Periodic interrupt Set  */
  85 #define RCR2_RTCEN      0x08    /* ENable RTC              */
  86 #define RCR2_ADJ        0x04    /* ADJustment (30-second)  */
  87 #define RCR2_RESET      0x02    /* Reset bit               */
  88 #define RCR2_START      0x01    /* Start bit               */
  89
  90 struct sh_rtc {
  91         void __iomem            *regbase;
  92         unsigned long           regsize;
  93         struct resource         *res;
  94         int                     alarm_irq;
  95         int                     periodic_irq;
  96         int                     carry_irq;
  97         struct clk              *clk;
  98         struct rtc_device       *rtc_dev;
  99         spinlock_t              lock;
 100         unsigned long           capabilities;   /* See asm/rtc.h for cap bits */
 101         unsigned short          periodic_freq;
 102 };
 103
 104 static int __sh_rtc_interrupt(struct sh_rtc *rtc)
 105 {
 106         unsigned int tmp, pending;
 107
 108         tmp = readb(rtc->regbase + RCR1);
 109         pending = tmp & RCR1_CF;
 110         tmp &= ~RCR1_CF;
 111         writeb(tmp, rtc->regbase + RCR1);
 112
 113         /* Users have requested One x Second IRQ */
 114         if (pending && rtc->periodic_freq & PF_OXS)
 115                 rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
 116
 117         return pending;
 118 }
 119
 120 static int __sh_rtc_alarm(struct sh_rtc *rtc)
 121 {
 122         unsigned int tmp, pending;
 123
 124         tmp = readb(rtc->regbase + RCR1);
 125         pending = tmp & RCR1_AF;
 126         tmp &= ~(RCR1_AF | RCR1_AIE);
 127         writeb(tmp, rtc->regbase + RCR1);
 128
 129         if (pending)
 130                 rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
 131
 132         return pending;
 133 }
 134
 135 static int __sh_rtc_periodic(struct sh_rtc *rtc)
 136 {
 137         struct rtc_device *rtc_dev = rtc->rtc_dev;
 138         struct rtc_task *irq_task;
 139         unsigned int tmp, pending;
 140
 141         tmp = readb(rtc->regbase + RCR2);
 142         pending = tmp & RCR2_PEF;
 143         tmp &= ~RCR2_PEF;
 144         writeb(tmp, rtc->regbase + RCR2);
 145
 146         if (!pending)
 147                 return 0;
 148
 149         /* Half period enabled than one skipped and the next notified */
 150         if ((rtc->periodic_freq & PF_HP) && (rtc->periodic_freq & PF_COUNT))
 151                 rtc->periodic_freq &= ~PF_COUNT;
 152         else {
 153                 if (rtc->periodic_freq & PF_HP)
 154                         rtc->periodic_freq |= PF_COUNT;
 155                 if (rtc->periodic_freq & PF_KOU) {
 156                         spin_lock(&rtc_dev->irq_task_lock);
 157                         irq_task = rtc_dev->irq_task;
 158                         if (irq_task)
 159                                 irq_task->func(irq_task->private_data);
 160                         spin_unlock(&rtc_dev->irq_task_lock);
 161                 } else
 162                         rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
 163         }
 164
 165         return pending;
 166 }
 167
 168 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
 169 {
 170         struct sh_rtc *rtc = dev_id;
 171         int ret;
 172
 173         spin_lock(&rtc->lock);
 174         ret = __sh_rtc_interrupt(rtc);
 175         spin_unlock(&rtc->lock);
 176
 177         return IRQ_RETVAL(ret);
 178 }
 179
 180 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
 181 {
 182         struct sh_rtc *rtc = dev_id;
 183         int ret;
 184
 185         spin_lock(&rtc->lock);
 186         ret = __sh_rtc_alarm(rtc);
 187         spin_unlock(&rtc->lock);
 188
 189         return IRQ_RETVAL(ret);
 190 }
 191
 192 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
 193 {
 194         struct sh_rtc *rtc = dev_id;
 195         int ret;
 196
 197         spin_lock(&rtc->lock);
 198         ret = __sh_rtc_periodic(rtc);
 199         spin_unlock(&rtc->lock);
 200
 201         return IRQ_RETVAL(ret);
 202 }
 203
 204 static irqreturn_t sh_rtc_shared(int irq, void *dev_id)
 205 {
 206         struct sh_rtc *rtc = dev_id;
 207         int ret;
 208
 209         spin_lock(&rtc->lock);
 210         ret = __sh_rtc_interrupt(rtc);
 211         ret |= __sh_rtc_alarm(rtc);
 212         ret |= __sh_rtc_periodic(rtc);
 213         spin_unlock(&rtc->lock);
 214
 215         return IRQ_RETVAL(ret);
 216 }
 217
 218 static int sh_rtc_irq_set_state(struct device *dev, int enable)
 219 {
 220         struct sh_rtc *rtc = dev_get_drvdata(dev);
 221         unsigned int tmp;
 222
 223         spin_lock_irq(&rtc->lock);
 224
 225         tmp = readb(rtc->regbase + RCR2);
 226
 227         if (enable) {
 228                 rtc->periodic_freq |= PF_KOU;
 229                 tmp &= ~RCR2_PEF;       /* Clear PES bit */
 230                 tmp |= (rtc->periodic_freq & ~PF_HP);   /* Set PES2-0 */
 231         } else {
 232                 rtc->periodic_freq &= ~PF_KOU;
 233                 tmp &= ~(RCR2_PESMASK | RCR2_PEF);
 234         }
 235
 236         writeb(tmp, rtc->regbase + RCR2);
 237
 238         spin_unlock_irq(&rtc->lock);
 239
 240         return 0;
 241 }
 242
 243 static int sh_rtc_irq_set_freq(struct device *dev, int freq)
 244 {
 245         struct sh_rtc *rtc = dev_get_drvdata(dev);
 246         int tmp, ret = 0;
 247
 248         spin_lock_irq(&rtc->lock);
 249         tmp = rtc->periodic_freq & PF_MASK;
 250
 251         switch (freq) {
 252         case 0:
 253                 rtc->periodic_freq = 0x00;
 254                 break;
 255         case 1:
 256                 rtc->periodic_freq = 0x60;
 257                 break;
 258         case 2:
 259                 rtc->periodic_freq = 0x50;
 260                 break;
 261         case 4:
 262                 rtc->periodic_freq = 0x40;
 263                 break;
 264         case 8:
 265                 rtc->periodic_freq = 0x30 | PF_HP;
 266                 break;
 267         case 16:
 268                 rtc->periodic_freq = 0x30;
 269                 break;
 270         case 32:
 271                 rtc->periodic_freq = 0x20 | PF_HP;
 272                 break;
 273         case 64:
 274                 rtc->periodic_freq = 0x20;
 275                 break;
 276         case 128:
 277                 rtc->periodic_freq = 0x10 | PF_HP;
 278                 break;
 279         case 256:
 280                 rtc->periodic_freq = 0x10;
 281                 break;
 282         default:
 283                 ret = -ENOTSUPP;
 284         }
 285
 286         if (ret == 0)
 287                 rtc->periodic_freq |= tmp;
 288
 289         spin_unlock_irq(&rtc->lock);
 290         return ret;
 291 }
 292
 293 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
 294 {
 295         struct sh_rtc *rtc = dev_get_drvdata(dev);
 296         unsigned int tmp;
 297
 298         spin_lock_irq(&rtc->lock);
 299
 300         tmp = readb(rtc->regbase + RCR1);
 301
 302         if (enable)
 303                 tmp |= RCR1_AIE;
 304         else
 305                 tmp &= ~RCR1_AIE;
 306
 307         writeb(tmp, rtc->regbase + RCR1);
 308
 309         spin_unlock_irq(&rtc->lock);
 310 }
 311
 312 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
 313 {
 314         struct sh_rtc *rtc = dev_get_drvdata(dev);
 315         unsigned int tmp;
 316
 317         tmp = readb(rtc->regbase + RCR1);
 318         seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no");
 319
 320         tmp = readb(rtc->regbase + RCR2);
 321         seq_printf(seq, "periodic_IRQ\t: %s\n",
 322                    (tmp & RCR2_PESMASK) ? "yes" : "no");
 323
 324         return 0;
 325 }
 326
 327 static inline void sh_rtc_setcie(struct device *dev, unsigned int enable)
 328 {
 329         struct sh_rtc *rtc = dev_get_drvdata(dev);
 330         unsigned int tmp;
 331
 332         spin_lock_irq(&rtc->lock);
 333
 334         tmp = readb(rtc->regbase + RCR1);
 335
 336         if (!enable)
 337                 tmp &= ~RCR1_CIE;
 338         else
 339                 tmp |= RCR1_CIE;
 340
 341         writeb(tmp, rtc->regbase + RCR1);
 342
 343         spin_unlock_irq(&rtc->lock);
 344 }
 345
 346 static int sh_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 347 {
 348         sh_rtc_setaie(dev, enabled);
 349         return 0;
 350 }
 351
 352 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
 353 {
 354         struct platform_device *pdev = to_platform_device(dev);
 355         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 356         unsigned int sec128, sec2, yr, yr100, cf_bit;
 357
 358         do {
 359                 unsigned int tmp;
 360
 361                 spin_lock_irq(&rtc->lock);
 362
 363                 tmp = readb(rtc->regbase + RCR1);
 364                 tmp &= ~RCR1_CF; /* Clear CF-bit */
 365                 tmp |= RCR1_CIE;
 366                 writeb(tmp, rtc->regbase + RCR1);
 367
 368                 sec128 = readb(rtc->regbase + R64CNT);
 369
 370                 tm->tm_sec      = bcd2bin(readb(rtc->regbase + RSECCNT));
 371                 tm->tm_min      = bcd2bin(readb(rtc->regbase + RMINCNT));
 372                 tm->tm_hour     = bcd2bin(readb(rtc->regbase + RHRCNT));
 373                 tm->tm_wday     = bcd2bin(readb(rtc->regbase + RWKCNT));
 374                 tm->tm_mday     = bcd2bin(readb(rtc->regbase + RDAYCNT));
 375                 tm->tm_mon      = bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
 376
 377                 if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
 378                         yr  = readw(rtc->regbase + RYRCNT);
 379                         yr100 = bcd2bin(yr >> 8);
 380                         yr &= 0xff;
 381                 } else {
 382                         yr  = readb(rtc->regbase + RYRCNT);
 383                         yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
 384                 }
 385
 386                 tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
 387
 388                 sec2 = readb(rtc->regbase + R64CNT);
 389                 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
 390
 391                 spin_unlock_irq(&rtc->lock);
 392         } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
 393
 394 #if RTC_BIT_INVERTED != 0
 395         if ((sec128 & RTC_BIT_INVERTED))
 396                 tm->tm_sec--;
 397 #endif
 398
 399         /* only keep the carry interrupt enabled if UIE is on */
 400         if (!(rtc->periodic_freq & PF_OXS))
 401                 sh_rtc_setcie(dev, 0);
 402
 403         dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 404                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 405                 __func__,
 406                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 407                 tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
 408
 409         return rtc_valid_tm(tm);
 410 }
 411
 412 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
 413 {
 414         struct platform_device *pdev = to_platform_device(dev);
 415         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 416         unsigned int tmp;
 417         int year;
 418
 419         spin_lock_irq(&rtc->lock);
 420
 421         /* Reset pre-scaler & stop RTC */
 422         tmp = readb(rtc->regbase + RCR2);
 423         tmp |= RCR2_RESET;
 424         tmp &= ~RCR2_START;
 425         writeb(tmp, rtc->regbase + RCR2);
 426
 427         writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
 428         writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
 429         writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
 430         writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
 431         writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
 432         writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
 433
 434         if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
 435                 year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
 436                         bin2bcd(tm->tm_year % 100);
 437                 writew(year, rtc->regbase + RYRCNT);
 438         } else {
 439                 year = tm->tm_year % 100;
 440                 writeb(bin2bcd(year), rtc->regbase + RYRCNT);
 441         }
 442
 443         /* Start RTC */
 444         tmp = readb(rtc->regbase + RCR2);
 445         tmp &= ~RCR2_RESET;
 446         tmp |= RCR2_RTCEN | RCR2_START;
 447         writeb(tmp, rtc->regbase + RCR2);
 448
 449         spin_unlock_irq(&rtc->lock);
 450
 451         return 0;
 452 }
 453
 454 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
 455 {
 456         unsigned int byte;
 457         int value = 0xff;       /* return 0xff for ignored values */
 458
 459         byte = readb(rtc->regbase + reg_off);
 460         if (byte & AR_ENB) {
 461                 byte &= ~AR_ENB;        /* strip the enable bit */
 462                 value = bcd2bin(byte);
 463         }
 464
 465         return value;
 466 }
 467
 468 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
 469 {
 470         struct platform_device *pdev = to_platform_device(dev);
 471         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 472         struct rtc_time *tm = &wkalrm->time;
 473
 474         spin_lock_irq(&rtc->lock);
 475
 476         tm->tm_sec      = sh_rtc_read_alarm_value(rtc, RSECAR);
 477         tm->tm_min      = sh_rtc_read_alarm_value(rtc, RMINAR);
 478         tm->tm_hour     = sh_rtc_read_alarm_value(rtc, RHRAR);
 479         tm->tm_wday     = sh_rtc_read_alarm_value(rtc, RWKAR);
 480         tm->tm_mday     = sh_rtc_read_alarm_value(rtc, RDAYAR);
 481         tm->tm_mon      = sh_rtc_read_alarm_value(rtc, RMONAR);
 482         if (tm->tm_mon > 0)
 483                 tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
 484
 485         wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
 486
 487         spin_unlock_irq(&rtc->lock);
 488
 489         return 0;
 490 }
 491
 492 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
 493                                             int value, int reg_off)
 494 {
 495         /* < 0 for a value that is ignored */
 496         if (value < 0)
 497                 writeb(0, rtc->regbase + reg_off);
 498         else
 499                 writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
 500 }
 501
 502 static int sh_rtc_check_alarm(struct rtc_time *tm)
 503 {
 504         /*
 505          * The original rtc says anything > 0xc0 is "don't care" or "match
 506          * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
 507          * The original rtc doesn't support years - some things use -1 and
 508          * some 0xffff. We use -1 to make out tests easier.
 509          */
 510         if (tm->tm_year == 0xffff)
 511                 tm->tm_year = -1;
 512         if (tm->tm_mon >= 0xff)
 513                 tm->tm_mon = -1;
 514         if (tm->tm_mday >= 0xff)
 515                 tm->tm_mday = -1;
 516         if (tm->tm_wday >= 0xff)
 517                 tm->tm_wday = -1;
 518         if (tm->tm_hour >= 0xff)
 519                 tm->tm_hour = -1;
 520         if (tm->tm_min >= 0xff)
 521                 tm->tm_min = -1;
 522         if (tm->tm_sec >= 0xff)
 523                 tm->tm_sec = -1;
 524
 525         if (tm->tm_year > 9999 ||
 526                 tm->tm_mon >= 12 ||
 527                 tm->tm_mday == 0 || tm->tm_mday >= 32 ||
 528                 tm->tm_wday >= 7 ||
 529                 tm->tm_hour >= 24 ||
 530                 tm->tm_min >= 60 ||
 531                 tm->tm_sec >= 60)
 532                 return -EINVAL;
 533
 534         return 0;
 535 }
 536
 537 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
 538 {
 539         struct platform_device *pdev = to_platform_device(dev);
 540         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 541         unsigned int rcr1;
 542         struct rtc_time *tm = &wkalrm->time;
 543         int mon, err;
 544
 545         err = sh_rtc_check_alarm(tm);
 546         if (unlikely(err < 0))
 547                 return err;
 548
 549         spin_lock_irq(&rtc->lock);
 550
 551         /* disable alarm interrupt and clear the alarm flag */
 552         rcr1 = readb(rtc->regbase + RCR1);
 553         rcr1 &= ~(RCR1_AF | RCR1_AIE);
 554         writeb(rcr1, rtc->regbase + RCR1);
 555
 556         /* set alarm time */
 557         sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
 558         sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
 559         sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
 560         sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
 561         sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
 562         mon = tm->tm_mon;
 563         if (mon >= 0)
 564                 mon += 1;
 565         sh_rtc_write_alarm_value(rtc, mon, RMONAR);
 566
 567         if (wkalrm->enabled) {
 568                 rcr1 |= RCR1_AIE;
 569                 writeb(rcr1, rtc->regbase + RCR1);
 570         }
 571
 572         spin_unlock_irq(&rtc->lock);
 573
 574         return 0;
 575 }
 576
 577 static struct rtc_class_ops sh_rtc_ops = {
 578         .read_time      = sh_rtc_read_time,
 579         .set_time       = sh_rtc_set_time,
 580         .read_alarm     = sh_rtc_read_alarm,
 581         .set_alarm      = sh_rtc_set_alarm,
 582         .proc           = sh_rtc_proc,
 583         .alarm_irq_enable = sh_rtc_alarm_irq_enable,
 584 };
 585
 586 static int __init sh_rtc_probe(struct platform_device *pdev)
 587 {
 588         struct sh_rtc *rtc;
 589         struct resource *res;
 590         struct rtc_time r;
 591         char clk_name[6];
 592         int clk_id, ret;
 593
 594         rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 595         if (unlikely(!rtc))
 596                 return -ENOMEM;
 597
 598         spin_lock_init(&rtc->lock);
 599
 600         /* get periodic/carry/alarm irqs */
 601         ret = platform_get_irq(pdev, 0);
 602         if (unlikely(ret <= 0)) {
 603                 dev_err(&pdev->dev, "No IRQ resource\n");
 604                 return -ENOENT;
 605         }
 606
 607         rtc->periodic_irq = ret;
 608         rtc->carry_irq = platform_get_irq(pdev, 1);
 609         rtc->alarm_irq = platform_get_irq(pdev, 2);
 610
 611         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 612         if (unlikely(res == NULL)) {
 613                 dev_err(&pdev->dev, "No IO resource\n");
 614                 return -ENOENT;
 615         }
 616
 617         rtc->regsize = resource_size(res);
 618
 619         rtc->res = devm_request_mem_region(&pdev->dev, res->start,
 620                                         rtc->regsize, pdev->name);
 621         if (unlikely(!rtc->res))
 622                 return -EBUSY;
 623
 624         rtc->regbase = devm_ioremap_nocache(&pdev->dev, rtc->res->start,
 625                                         rtc->regsize);
 626         if (unlikely(!rtc->regbase))
 627                 return -EINVAL;
 628
 629         clk_id = pdev->id;
 630         /* With a single device, the clock id is still "rtc0" */
 631         if (clk_id < 0)
 632                 clk_id = 0;
 633
 634         snprintf(clk_name, sizeof(clk_name), "rtc%d", clk_id);
 635
 636         rtc->clk = devm_clk_get(&pdev->dev, clk_name);
 637         if (IS_ERR(rtc->clk)) {
 638                 /*
 639                  * No error handling for rtc->clk intentionally, not all
 640                  * platforms will have a unique clock for the RTC, and
 641                  * the clk API can handle the struct clk pointer being
 642                  * NULL.
 643                  */
 644                 rtc->clk = NULL;
 645         }
 646
 647         clk_enable(rtc->clk);
 648
 649         rtc->capabilities = RTC_DEF_CAPABILITIES;
 650         if (dev_get_platdata(&pdev->dev)) {
 651                 struct sh_rtc_platform_info *pinfo =
 652                         dev_get_platdata(&pdev->dev);
 653
 654                 /*
 655                  * Some CPUs have special capabilities in addition to the
 656                  * default set. Add those in here.
 657                  */
 658                 rtc->capabilities |= pinfo->capabilities;
 659         }
 660
 661         if (rtc->carry_irq <= 0) {
 662                 /* register shared periodic/carry/alarm irq */
 663                 ret = devm_request_irq(&pdev->dev, rtc->periodic_irq,
 664                                 sh_rtc_shared, 0, "sh-rtc", rtc);
 665                 if (unlikely(ret)) {
 666                         dev_err(&pdev->dev,
 667                                 "request IRQ failed with %d, IRQ %d\n", ret,
 668                                 rtc->periodic_irq);
 669                         goto err_unmap;
 670                 }
 671         } else {
 672                 /* register periodic/carry/alarm irqs */
 673                 ret = devm_request_irq(&pdev->dev, rtc->periodic_irq,
 674                                 sh_rtc_periodic, 0, "sh-rtc period", rtc);
 675                 if (unlikely(ret)) {
 676                         dev_err(&pdev->dev,
 677                                 "request period IRQ failed with %d, IRQ %d\n",
 678                                 ret, rtc->periodic_irq);
 679                         goto err_unmap;
 680                 }
 681
 682                 ret = devm_request_irq(&pdev->dev, rtc->carry_irq,
 683                                 sh_rtc_interrupt, 0, "sh-rtc carry", rtc);
 684                 if (unlikely(ret)) {
 685                         dev_err(&pdev->dev,
 686                                 "request carry IRQ failed with %d, IRQ %d\n",
 687                                 ret, rtc->carry_irq);
 688                         goto err_unmap;
 689                 }
 690
 691                 ret = devm_request_irq(&pdev->dev, rtc->alarm_irq,
 692                                 sh_rtc_alarm, 0, "sh-rtc alarm", rtc);
 693                 if (unlikely(ret)) {
 694                         dev_err(&pdev->dev,
 695                                 "request alarm IRQ failed with %d, IRQ %d\n",
 696                                 ret, rtc->alarm_irq);
 697                         goto err_unmap;
 698                 }
 699         }
 700
 701         platform_set_drvdata(pdev, rtc);
 702
 703         /* everything disabled by default */
 704         sh_rtc_irq_set_freq(&pdev->dev, 0);
 705         sh_rtc_irq_set_state(&pdev->dev, 0);
 706         sh_rtc_setaie(&pdev->dev, 0);
 707         sh_rtc_setcie(&pdev->dev, 0);
 708
 709         rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "sh",
 710                                            &sh_rtc_ops, THIS_MODULE);
 711         if (IS_ERR(rtc->rtc_dev)) {
 712                 ret = PTR_ERR(rtc->rtc_dev);
 713                 goto err_unmap;
 714         }
 715
 716         rtc->rtc_dev->max_user_freq = 256;
 717
 718         /* reset rtc to epoch 0 if time is invalid */
 719         if (rtc_read_time(rtc->rtc_dev, &r) < 0) {
 720                 rtc_time_to_tm(0, &r);
 721                 rtc_set_time(rtc->rtc_dev, &r);
 722         }
 723
 724         device_init_wakeup(&pdev->dev, 1);
 725         return 0;
 726
 727 err_unmap:
 728         clk_disable(rtc->clk);
 729
 730         return ret;
 731 }
 732
 733 static int __exit sh_rtc_remove(struct platform_device *pdev)
 734 {
 735         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 736
 737         sh_rtc_irq_set_state(&pdev->dev, 0);
 738
 739         sh_rtc_setaie(&pdev->dev, 0);
 740         sh_rtc_setcie(&pdev->dev, 0);
 741
 742         clk_disable(rtc->clk);
 743
 744         return 0;
 745 }
 746
 747 static void sh_rtc_set_irq_wake(struct device *dev, int enabled)
 748 {
 749         struct platform_device *pdev = to_platform_device(dev);
 750         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 751
 752         irq_set_irq_wake(rtc->periodic_irq, enabled);
 753
 754         if (rtc->carry_irq > 0) {
 755                 irq_set_irq_wake(rtc->carry_irq, enabled);
 756                 irq_set_irq_wake(rtc->alarm_irq, enabled);
 757         }
 758 }
 759
 760 #ifdef CONFIG_PM_SLEEP
 761 static int sh_rtc_suspend(struct device *dev)
 762 {
 763         if (device_may_wakeup(dev))
 764                 sh_rtc_set_irq_wake(dev, 1);
 765
 766         return 0;
 767 }
 768
 769 static int sh_rtc_resume(struct device *dev)
 770 {
 771         if (device_may_wakeup(dev))
 772                 sh_rtc_set_irq_wake(dev, 0);
 773
 774         return 0;
 775 }
 776 #endif
 777
 778 static SIMPLE_DEV_PM_OPS(sh_rtc_pm_ops, sh_rtc_suspend, sh_rtc_resume);
 779
 780 static struct platform_driver sh_rtc_platform_driver = {
 781         .driver         = {
 782                 .name   = DRV_NAME,
 783                 .pm     = &sh_rtc_pm_ops,
 784         },
 785         .remove         = __exit_p(sh_rtc_remove),
 786 };
 787
 788 module_platform_driver_probe(sh_rtc_platform_driver, sh_rtc_probe);
 789
 790 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
 791 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
 792               "Jamie Lenehan <lenehan@twibble.org>, "
 793               "Angelo Castello <angelo.castello@st.com>");
 794 MODULE_LICENSE("GPL");
 795 MODULE_ALIAS("platform:" DRV_NAME);