drivers/rtc/rtc-sh.c

   1 /*
   2  * SuperH On-Chip RTC Support
   3  *
   4  * Copyright (C) 2006  Paul Mundt
   5  *
   6  * Based on the old arch/sh/kernel/cpu/rtc.c by:
   7  *
   8  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
   9  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/bcd.h>
  18 #include <linux/rtc.h>
  19 #include <linux/init.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/spinlock.h>
  24 #include <asm/io.h>
  25
  26 #ifdef CONFIG_CPU_SH3
  27 #define rtc_reg_size            sizeof(u16)
  28 #define RTC_BIT_INVERTED        0       /* No bug on SH7708, SH7709A */
  29 #elif defined(CONFIG_CPU_SH4)
  30 #define rtc_reg_size            sizeof(u32)
  31 #define RTC_BIT_INVERTED        0x40    /* bug on SH7750, SH7750S */
  32 #endif
  33
  34 #define RTC_REG(r)      ((r) * rtc_reg_size)
  35
  36 #define R64CNT          RTC_REG(0)
  37 #define RSECCNT         RTC_REG(1)
  38 #define RMINCNT         RTC_REG(2)
  39 #define RHRCNT          RTC_REG(3)
  40 #define RWKCNT          RTC_REG(4)
  41 #define RDAYCNT         RTC_REG(5)
  42 #define RMONCNT         RTC_REG(6)
  43 #define RYRCNT          RTC_REG(7)
  44 #define RSECAR          RTC_REG(8)
  45 #define RMINAR          RTC_REG(9)
  46 #define RHRAR           RTC_REG(10)
  47 #define RWKAR           RTC_REG(11)
  48 #define RDAYAR          RTC_REG(12)
  49 #define RMONAR          RTC_REG(13)
  50 #define RCR1            RTC_REG(14)
  51 #define RCR2            RTC_REG(15)
  52
  53 /* RCR1 Bits */
  54 #define RCR1_CF         0x80    /* Carry Flag             */
  55 #define RCR1_CIE        0x10    /* Carry Interrupt Enable */
  56 #define RCR1_AIE        0x08    /* Alarm Interrupt Enable */
  57 #define RCR1_AF         0x01    /* Alarm Flag             */
  58
  59 /* RCR2 Bits */
  60 #define RCR2_PEF        0x80    /* PEriodic interrupt Flag */
  61 #define RCR2_PESMASK    0x70    /* Periodic interrupt Set  */
  62 #define RCR2_RTCEN      0x08    /* ENable RTC              */
  63 #define RCR2_ADJ        0x04    /* ADJustment (30-second)  */
  64 #define RCR2_RESET      0x02    /* Reset bit               */
  65 #define RCR2_START      0x01    /* Start bit               */
  66
  67 struct sh_rtc {
  68         void __iomem *regbase;
  69         unsigned long regsize;
  70         struct resource *res;
  71         unsigned int alarm_irq, periodic_irq, carry_irq;
  72         struct rtc_device *rtc_dev;
  73         spinlock_t lock;
  74 };
  75
  76 static irqreturn_t sh_rtc_interrupt(int irq, void *id)
  77 {
  78         struct platform_device *pdev = id;
  79         struct sh_rtc *rtc = platform_get_drvdata(pdev);
  80         unsigned int tmp, events = 0;
  81
  82         spin_lock(&rtc->lock);
  83
  84         tmp = readb(rtc->regbase + RCR1);
  85
  86         if (tmp & RCR1_AF)
  87                 events |= RTC_AF | RTC_IRQF;
  88
  89         tmp &= ~(RCR1_CF | RCR1_AF);
  90
  91         writeb(tmp, rtc->regbase + RCR1);
  92
  93         rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);
  94
  95         spin_unlock(&rtc->lock);
  96
  97         return IRQ_HANDLED;
  98 }
  99
 100 static irqreturn_t sh_rtc_periodic(int irq, void *id)
 101 {
 102         struct sh_rtc *rtc = dev_get_drvdata(id);
 103
 104         spin_lock(&rtc->lock);
 105
 106         rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF | RTC_IRQF);
 107
 108         spin_unlock(&rtc->lock);
 109
 110         return IRQ_HANDLED;
 111 }
 112
 113 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
 114 {
 115         struct sh_rtc *rtc = dev_get_drvdata(dev);
 116         unsigned int tmp;
 117
 118         spin_lock_irq(&rtc->lock);
 119
 120         tmp = readb(rtc->regbase + RCR2);
 121
 122         if (enable) {
 123                 tmp &= ~RCR2_PESMASK;
 124                 tmp |= RCR2_PEF | (2 << 4);
 125         } else
 126                 tmp &= ~(RCR2_PESMASK | RCR2_PEF);
 127
 128         writeb(tmp, rtc->regbase + RCR2);
 129
 130         spin_unlock_irq(&rtc->lock);
 131 }
 132
 133 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
 134 {
 135         struct sh_rtc *rtc = dev_get_drvdata(dev);
 136         unsigned int tmp;
 137
 138         spin_lock_irq(&rtc->lock);
 139
 140         tmp = readb(rtc->regbase + RCR1);
 141
 142         if (enable)
 143                 tmp |= RCR1_AIE;
 144         else
 145                 tmp &= ~RCR1_AIE;
 146
 147         writeb(tmp, rtc->regbase + RCR1);
 148
 149         spin_unlock_irq(&rtc->lock);
 150 }
 151
 152 static int sh_rtc_open(struct device *dev)
 153 {
 154         struct sh_rtc *rtc = dev_get_drvdata(dev);
 155         unsigned int tmp;
 156         int ret;
 157
 158         tmp = readb(rtc->regbase + RCR1);
 159         tmp &= ~RCR1_CF;
 160         tmp |= RCR1_CIE;
 161         writeb(tmp, rtc->regbase + RCR1);
 162
 163         ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, SA_INTERRUPT,
 164                           "sh-rtc period", dev);
 165         if (unlikely(ret)) {
 166                 dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
 167                         ret, rtc->periodic_irq);
 168                 return ret;
 169         }
 170
 171         ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, SA_INTERRUPT,
 172                           "sh-rtc carry", dev);
 173         if (unlikely(ret)) {
 174                 dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
 175                         ret, rtc->carry_irq);
 176                 free_irq(rtc->periodic_irq, dev);
 177                 goto err_bad_carry;
 178         }
 179
 180         ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, SA_INTERRUPT,
 181                           "sh-rtc alarm", dev);
 182         if (unlikely(ret)) {
 183                 dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
 184                         ret, rtc->alarm_irq);
 185                 goto err_bad_alarm;
 186         }
 187
 188         return 0;
 189
 190 err_bad_alarm:
 191         free_irq(rtc->carry_irq, dev);
 192 err_bad_carry:
 193         free_irq(rtc->periodic_irq, dev);
 194
 195         return ret;
 196 }
 197
 198 static void sh_rtc_release(struct device *dev)
 199 {
 200         struct sh_rtc *rtc = dev_get_drvdata(dev);
 201
 202         sh_rtc_setpie(dev, 0);
 203
 204         free_irq(rtc->periodic_irq, dev);
 205         free_irq(rtc->carry_irq, dev);
 206         free_irq(rtc->alarm_irq, dev);
 207 }
 208
 209 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
 210 {
 211         struct sh_rtc *rtc = dev_get_drvdata(dev);
 212         unsigned int tmp;
 213
 214         tmp = readb(rtc->regbase + RCR1);
 215         seq_printf(seq, "alarm_IRQ\t: %s\n",
 216                    (tmp & RCR1_AIE) ? "yes" : "no");
 217         seq_printf(seq, "carry_IRQ\t: %s\n",
 218                    (tmp & RCR1_CIE) ? "yes" : "no");
 219
 220         tmp = readb(rtc->regbase + RCR2);
 221         seq_printf(seq, "periodic_IRQ\t: %s\n",
 222                    (tmp & RCR2_PEF) ? "yes" : "no");
 223
 224         return 0;
 225 }
 226
 227 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 228 {
 229         unsigned int ret = -ENOIOCTLCMD;
 230
 231         switch (cmd) {
 232         case RTC_PIE_OFF:
 233         case RTC_PIE_ON:
 234                 sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
 235                 ret = 0;
 236                 break;
 237         case RTC_AIE_OFF:
 238         case RTC_AIE_ON:
 239                 sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
 240                 ret = 0;
 241                 break;
 242         }
 243
 244         return ret;
 245 }
 246
 247 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
 248 {
 249         struct platform_device *pdev = to_platform_device(dev);
 250         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 251         unsigned int sec128, sec2, yr, yr100, cf_bit;
 252
 253         do {
 254                 unsigned int tmp;
 255
 256                 spin_lock_irq(&rtc->lock);
 257
 258                 tmp = readb(rtc->regbase + RCR1);
 259                 tmp &= ~RCR1_CF; /* Clear CF-bit */
 260                 tmp |= RCR1_CIE;
 261                 writeb(tmp, rtc->regbase + RCR1);
 262
 263                 sec128 = readb(rtc->regbase + R64CNT);
 264
 265                 tm->tm_sec      = BCD2BIN(readb(rtc->regbase + RSECCNT));
 266                 tm->tm_min      = BCD2BIN(readb(rtc->regbase + RMINCNT));
 267                 tm->tm_hour     = BCD2BIN(readb(rtc->regbase + RHRCNT));
 268                 tm->tm_wday     = BCD2BIN(readb(rtc->regbase + RWKCNT));
 269                 tm->tm_mday     = BCD2BIN(readb(rtc->regbase + RDAYCNT));
 270                 tm->tm_mon      = BCD2BIN(readb(rtc->regbase + RMONCNT));
 271
 272 #if defined(CONFIG_CPU_SH4)
 273                 yr  = readw(rtc->regbase + RYRCNT);
 274                 yr100 = BCD2BIN(yr >> 8);
 275                 yr &= 0xff;
 276 #else
 277                 yr  = readb(rtc->regbase + RYRCNT);
 278                 yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
 279 #endif
 280
 281                 tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
 282
 283                 sec2 = readb(rtc->regbase + R64CNT);
 284                 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
 285
 286                 spin_unlock_irq(&rtc->lock);
 287         } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
 288
 289 #if RTC_BIT_INVERTED != 0
 290         if ((sec128 & RTC_BIT_INVERTED))
 291                 tm->tm_sec--;
 292 #endif
 293
 294         dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 295                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 296                 __FUNCTION__,
 297                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 298                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 299
 300         if (rtc_valid_tm(tm) < 0)
 301                 dev_err(dev, "invalid date\n");
 302
 303         return 0;
 304 }
 305
 306 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
 307 {
 308         struct platform_device *pdev = to_platform_device(dev);
 309         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 310         unsigned int tmp;
 311         int year;
 312
 313         spin_lock_irq(&rtc->lock);
 314
 315         /* Reset pre-scaler & stop RTC */
 316         tmp = readb(rtc->regbase + RCR2);
 317         tmp |= RCR2_RESET;
 318         writeb(tmp, rtc->regbase + RCR2);
 319
 320         writeb(BIN2BCD(tm->tm_sec),  rtc->regbase + RSECCNT);
 321         writeb(BIN2BCD(tm->tm_min),  rtc->regbase + RMINCNT);
 322         writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
 323         writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
 324         writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
 325         writeb(BIN2BCD(tm->tm_mon),  rtc->regbase + RMONCNT);
 326
 327 #ifdef CONFIG_CPU_SH3
 328         year = tm->tm_year % 100;
 329         writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
 330 #else
 331         year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
 332                 BIN2BCD(tm->tm_year % 100);
 333         writew(year, rtc->regbase + RYRCNT);
 334 #endif
 335
 336         /* Start RTC */
 337         tmp = readb(rtc->regbase + RCR2);
 338         tmp &= ~RCR2_RESET;
 339         tmp |= RCR2_RTCEN | RCR2_START;
 340         writeb(tmp, rtc->regbase + RCR2);
 341
 342         spin_unlock_irq(&rtc->lock);
 343
 344         return 0;
 345 }
 346
 347 static struct rtc_class_ops sh_rtc_ops = {
 348         .open           = sh_rtc_open,
 349         .release        = sh_rtc_release,
 350         .ioctl          = sh_rtc_ioctl,
 351         .read_time      = sh_rtc_read_time,
 352         .set_time       = sh_rtc_set_time,
 353         .proc           = sh_rtc_proc,
 354 };
 355
 356 static int __devinit sh_rtc_probe(struct platform_device *pdev)
 357 {
 358         struct sh_rtc *rtc;
 359         struct resource *res;
 360         int ret = -ENOENT;
 361
 362         rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
 363         if (unlikely(!rtc))
 364                 return -ENOMEM;
 365
 366         spin_lock_init(&rtc->lock);
 367
 368         rtc->periodic_irq = platform_get_irq(pdev, 0);
 369         if (unlikely(rtc->periodic_irq < 0)) {
 370                 dev_err(&pdev->dev, "No IRQ for period\n");
 371                 goto err_badres;
 372         }
 373
 374         rtc->carry_irq = platform_get_irq(pdev, 1);
 375         if (unlikely(rtc->carry_irq < 0)) {
 376                 dev_err(&pdev->dev, "No IRQ for carry\n");
 377                 goto err_badres;
 378         }
 379
 380         rtc->alarm_irq = platform_get_irq(pdev, 2);
 381         if (unlikely(rtc->alarm_irq < 0)) {
 382                 dev_err(&pdev->dev, "No IRQ for alarm\n");
 383                 goto err_badres;
 384         }
 385
 386         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 387         if (unlikely(res == NULL)) {
 388                 dev_err(&pdev->dev, "No IO resource\n");
 389                 goto err_badres;
 390         }
 391
 392         rtc->regsize = res->end - res->start + 1;
 393
 394         rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
 395         if (unlikely(!rtc->res)) {
 396                 ret = -EBUSY;
 397                 goto err_badres;
 398         }
 399
 400         rtc->regbase = (void __iomem *)rtc->res->start;
 401         if (unlikely(!rtc->regbase)) {
 402                 ret = -EINVAL;
 403                 goto err_badmap;
 404         }
 405
 406         rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
 407                                            &sh_rtc_ops, THIS_MODULE);
 408         if (IS_ERR(rtc)) {
 409                 ret = PTR_ERR(rtc->rtc_dev);
 410                 goto err_badmap;
 411         }
 412
 413         platform_set_drvdata(pdev, rtc);
 414
 415         return 0;
 416
 417 err_badmap:
 418         release_resource(rtc->res);
 419 err_badres:
 420         kfree(rtc);
 421
 422         return ret;
 423 }
 424
 425 static int __devexit sh_rtc_remove(struct platform_device *pdev)
 426 {
 427         struct sh_rtc *rtc = platform_get_drvdata(pdev);
 428
 429         if (likely(rtc->rtc_dev))
 430                 rtc_device_unregister(rtc->rtc_dev);
 431
 432         sh_rtc_setpie(&pdev->dev, 0);
 433         sh_rtc_setaie(&pdev->dev, 0);
 434
 435         release_resource(rtc->res);
 436
 437         platform_set_drvdata(pdev, NULL);
 438
 439         kfree(rtc);
 440
 441         return 0;
 442 }
 443 static struct platform_driver sh_rtc_platform_driver = {
 444         .driver         = {
 445                 .name   = "sh-rtc",
 446                 .owner  = THIS_MODULE,
 447         },
 448         .probe          = sh_rtc_probe,
 449         .remove         = __devexit_p(sh_rtc_remove),
 450 };
 451
 452 static int __init sh_rtc_init(void)
 453 {
 454         return platform_driver_register(&sh_rtc_platform_driver);
 455 }
 456
 457 static void __exit sh_rtc_exit(void)
 458 {
 459         platform_driver_unregister(&sh_rtc_platform_driver);
 460 }
 461
 462 module_init(sh_rtc_init);
 463 module_exit(sh_rtc_exit);
 464
 465 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
 466 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
 467 MODULE_LICENSE("GPL");