drivers/rtc/rtc-davinci.c

   1 /*
   2  * DaVinci Power Management and Real Time Clock Driver for TI platforms
   3  *
   4  * Copyright (C) 2009 Texas Instruments, Inc
   5  *
   6  * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22 #include <linux/kernel.h>
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/ioport.h>
  26 #include <linux/delay.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/rtc.h>
  29 #include <linux/bcd.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/io.h>
  32 #include <linux/slab.h>
  33
  34 /*
  35  * The DaVinci RTC is a simple RTC with the following
  36  * Sec: 0 - 59 : BCD count
  37  * Min: 0 - 59 : BCD count
  38  * Hour: 0 - 23 : BCD count
  39  * Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
  40  */
  41
  42 /* PRTC interface registers */
  43 #define DAVINCI_PRTCIF_PID              0x00
  44 #define PRTCIF_CTLR                     0x04
  45 #define PRTCIF_LDATA                    0x08
  46 #define PRTCIF_UDATA                    0x0C
  47 #define PRTCIF_INTEN                    0x10
  48 #define PRTCIF_INTFLG                   0x14
  49
  50 /* PRTCIF_CTLR bit fields */
  51 #define PRTCIF_CTLR_BUSY                BIT(31)
  52 #define PRTCIF_CTLR_SIZE                BIT(25)
  53 #define PRTCIF_CTLR_DIR                 BIT(24)
  54 #define PRTCIF_CTLR_BENU_MSB            BIT(23)
  55 #define PRTCIF_CTLR_BENU_3RD_BYTE       BIT(22)
  56 #define PRTCIF_CTLR_BENU_2ND_BYTE       BIT(21)
  57 #define PRTCIF_CTLR_BENU_LSB            BIT(20)
  58 #define PRTCIF_CTLR_BENU_MASK           (0x00F00000)
  59 #define PRTCIF_CTLR_BENL_MSB            BIT(19)
  60 #define PRTCIF_CTLR_BENL_3RD_BYTE       BIT(18)
  61 #define PRTCIF_CTLR_BENL_2ND_BYTE       BIT(17)
  62 #define PRTCIF_CTLR_BENL_LSB            BIT(16)
  63 #define PRTCIF_CTLR_BENL_MASK           (0x000F0000)
  64
  65 /* PRTCIF_INTEN bit fields */
  66 #define PRTCIF_INTEN_RTCSS              BIT(1)
  67 #define PRTCIF_INTEN_RTCIF              BIT(0)
  68 #define PRTCIF_INTEN_MASK               (PRTCIF_INTEN_RTCSS \
  69                                         | PRTCIF_INTEN_RTCIF)
  70
  71 /* PRTCIF_INTFLG bit fields */
  72 #define PRTCIF_INTFLG_RTCSS             BIT(1)
  73 #define PRTCIF_INTFLG_RTCIF             BIT(0)
  74 #define PRTCIF_INTFLG_MASK              (PRTCIF_INTFLG_RTCSS \
  75                                         | PRTCIF_INTFLG_RTCIF)
  76
  77 /* PRTC subsystem registers */
  78 #define PRTCSS_RTC_INTC_EXTENA1         (0x0C)
  79 #define PRTCSS_RTC_CTRL                 (0x10)
  80 #define PRTCSS_RTC_WDT                  (0x11)
  81 #define PRTCSS_RTC_TMR0                 (0x12)
  82 #define PRTCSS_RTC_TMR1                 (0x13)
  83 #define PRTCSS_RTC_CCTRL                (0x14)
  84 #define PRTCSS_RTC_SEC                  (0x15)
  85 #define PRTCSS_RTC_MIN                  (0x16)
  86 #define PRTCSS_RTC_HOUR                 (0x17)
  87 #define PRTCSS_RTC_DAY0                 (0x18)
  88 #define PRTCSS_RTC_DAY1                 (0x19)
  89 #define PRTCSS_RTC_AMIN                 (0x1A)
  90 #define PRTCSS_RTC_AHOUR                (0x1B)
  91 #define PRTCSS_RTC_ADAY0                (0x1C)
  92 #define PRTCSS_RTC_ADAY1                (0x1D)
  93 #define PRTCSS_RTC_CLKC_CNT             (0x20)
  94
  95 /* PRTCSS_RTC_INTC_EXTENA1 */
  96 #define PRTCSS_RTC_INTC_EXTENA1_MASK    (0x07)
  97
  98 /* PRTCSS_RTC_CTRL bit fields */
  99 #define PRTCSS_RTC_CTRL_WDTBUS          BIT(7)
 100 #define PRTCSS_RTC_CTRL_WEN             BIT(6)
 101 #define PRTCSS_RTC_CTRL_WDRT            BIT(5)
 102 #define PRTCSS_RTC_CTRL_WDTFLG          BIT(4)
 103 #define PRTCSS_RTC_CTRL_TE              BIT(3)
 104 #define PRTCSS_RTC_CTRL_TIEN            BIT(2)
 105 #define PRTCSS_RTC_CTRL_TMRFLG          BIT(1)
 106 #define PRTCSS_RTC_CTRL_TMMD            BIT(0)
 107
 108 /* PRTCSS_RTC_CCTRL bit fields */
 109 #define PRTCSS_RTC_CCTRL_CALBUSY        BIT(7)
 110 #define PRTCSS_RTC_CCTRL_DAEN           BIT(5)
 111 #define PRTCSS_RTC_CCTRL_HAEN           BIT(4)
 112 #define PRTCSS_RTC_CCTRL_MAEN           BIT(3)
 113 #define PRTCSS_RTC_CCTRL_ALMFLG         BIT(2)
 114 #define PRTCSS_RTC_CCTRL_AIEN           BIT(1)
 115 #define PRTCSS_RTC_CCTRL_CAEN           BIT(0)
 116
 117 static DEFINE_SPINLOCK(davinci_rtc_lock);
 118
 119 struct davinci_rtc {
 120         struct rtc_device               *rtc;
 121         void __iomem                    *base;
 122         resource_size_t                 pbase;
 123         size_t                          base_size;
 124         int                             irq;
 125 };
 126
 127 static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
 128                                u32 val, u32 addr)
 129 {
 130         writel(val, davinci_rtc->base + addr);
 131 }
 132
 133 static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
 134 {
 135         return readl(davinci_rtc->base + addr);
 136 }
 137
 138 static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
 139 {
 140         while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
 141                 cpu_relax();
 142 }
 143
 144 static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
 145                                unsigned long val, u8 addr)
 146 {
 147         rtcif_wait(davinci_rtc);
 148
 149         rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
 150         rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
 151
 152         rtcif_wait(davinci_rtc);
 153 }
 154
 155 static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
 156 {
 157         rtcif_wait(davinci_rtc);
 158
 159         rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
 160                     PRTCIF_CTLR);
 161
 162         rtcif_wait(davinci_rtc);
 163
 164         return rtcif_read(davinci_rtc, PRTCIF_LDATA);
 165 }
 166
 167 static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
 168 {
 169         while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
 170                PRTCSS_RTC_CCTRL_CALBUSY)
 171                 cpu_relax();
 172 }
 173
 174 static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
 175 {
 176         struct davinci_rtc *davinci_rtc = class_dev;
 177         unsigned long events = 0;
 178         u32 irq_flg;
 179         u8 alm_irq, tmr_irq;
 180         u8 rtc_ctrl, rtc_cctrl;
 181         int ret = IRQ_NONE;
 182
 183         irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
 184                   PRTCIF_INTFLG_RTCSS;
 185
 186         alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
 187                   PRTCSS_RTC_CCTRL_ALMFLG;
 188
 189         tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
 190                   PRTCSS_RTC_CTRL_TMRFLG;
 191
 192         if (irq_flg) {
 193                 if (alm_irq) {
 194                         events |= RTC_IRQF | RTC_AF;
 195                         rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 196                         rtc_cctrl |=  PRTCSS_RTC_CCTRL_ALMFLG;
 197                         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 198                 } else if (tmr_irq) {
 199                         events |= RTC_IRQF | RTC_PF;
 200                         rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
 201                         rtc_ctrl |=  PRTCSS_RTC_CTRL_TMRFLG;
 202                         rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
 203                 }
 204
 205                 rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
 206                                     PRTCIF_INTFLG);
 207                 rtc_update_irq(davinci_rtc->rtc, 1, events);
 208
 209                 ret = IRQ_HANDLED;
 210         }
 211
 212         return ret;
 213 }
 214
 215 static int
 216 davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 217 {
 218         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 219         u8 rtc_ctrl;
 220         unsigned long flags;
 221         int ret = 0;
 222
 223         spin_lock_irqsave(&davinci_rtc_lock, flags);
 224
 225         rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
 226
 227         switch (cmd) {
 228         case RTC_WIE_ON:
 229                 rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
 230                 break;
 231         case RTC_WIE_OFF:
 232                 rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
 233                 break;
 234         default:
 235                 ret = -ENOIOCTLCMD;
 236         }
 237
 238         rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
 239
 240         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 241
 242         return ret;
 243 }
 244
 245 static int convertfromdays(u16 days, struct rtc_time *tm)
 246 {
 247         int tmp_days, year, mon;
 248
 249         for (year = 2000;; year++) {
 250                 tmp_days = rtc_year_days(1, 12, year);
 251                 if (days >= tmp_days)
 252                         days -= tmp_days;
 253                 else {
 254                         for (mon = 0;; mon++) {
 255                                 tmp_days = rtc_month_days(mon, year);
 256                                 if (days >= tmp_days) {
 257                                         days -= tmp_days;
 258                                 } else {
 259                                         tm->tm_year = year - 1900;
 260                                         tm->tm_mon = mon;
 261                                         tm->tm_mday = days + 1;
 262                                         break;
 263                                 }
 264                         }
 265                         break;
 266                 }
 267         }
 268         return 0;
 269 }
 270
 271 static int convert2days(u16 *days, struct rtc_time *tm)
 272 {
 273         int i;
 274         *days = 0;
 275
 276         /* epoch == 1900 */
 277         if (tm->tm_year < 100 || tm->tm_year > 199)
 278                 return -EINVAL;
 279
 280         for (i = 2000; i < 1900 + tm->tm_year; i++)
 281                 *days += rtc_year_days(1, 12, i);
 282
 283         *days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
 284
 285         return 0;
 286 }
 287
 288 static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
 289 {
 290         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 291         u16 days = 0;
 292         u8 day0, day1;
 293         unsigned long flags;
 294
 295         spin_lock_irqsave(&davinci_rtc_lock, flags);
 296
 297         davinci_rtcss_calendar_wait(davinci_rtc);
 298         tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
 299
 300         davinci_rtcss_calendar_wait(davinci_rtc);
 301         tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
 302
 303         davinci_rtcss_calendar_wait(davinci_rtc);
 304         tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
 305
 306         davinci_rtcss_calendar_wait(davinci_rtc);
 307         day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
 308
 309         davinci_rtcss_calendar_wait(davinci_rtc);
 310         day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
 311
 312         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 313
 314         days |= day1;
 315         days <<= 8;
 316         days |= day0;
 317
 318         if (convertfromdays(days, tm) < 0)
 319                 return -EINVAL;
 320
 321         return 0;
 322 }
 323
 324 static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
 325 {
 326         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 327         u16 days;
 328         u8 rtc_cctrl;
 329         unsigned long flags;
 330
 331         if (convert2days(&days, tm) < 0)
 332                 return -EINVAL;
 333
 334         spin_lock_irqsave(&davinci_rtc_lock, flags);
 335
 336         davinci_rtcss_calendar_wait(davinci_rtc);
 337         rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
 338
 339         davinci_rtcss_calendar_wait(davinci_rtc);
 340         rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
 341
 342         davinci_rtcss_calendar_wait(davinci_rtc);
 343         rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
 344
 345         davinci_rtcss_calendar_wait(davinci_rtc);
 346         rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
 347
 348         davinci_rtcss_calendar_wait(davinci_rtc);
 349         rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
 350
 351         rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 352         rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
 353         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 354
 355         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 356
 357         return 0;
 358 }
 359
 360 static int davinci_rtc_alarm_irq_enable(struct device *dev,
 361                                         unsigned int enabled)
 362 {
 363         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 364         unsigned long flags;
 365         u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 366
 367         spin_lock_irqsave(&davinci_rtc_lock, flags);
 368
 369         if (enabled)
 370                 rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
 371                              PRTCSS_RTC_CCTRL_HAEN |
 372                              PRTCSS_RTC_CCTRL_MAEN |
 373                              PRTCSS_RTC_CCTRL_ALMFLG |
 374                              PRTCSS_RTC_CCTRL_AIEN;
 375         else
 376                 rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
 377
 378         davinci_rtcss_calendar_wait(davinci_rtc);
 379         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 380
 381         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 382
 383         return 0;
 384 }
 385
 386 static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 387 {
 388         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 389         u16 days = 0;
 390         u8 day0, day1;
 391         unsigned long flags;
 392
 393         spin_lock_irqsave(&davinci_rtc_lock, flags);
 394
 395         davinci_rtcss_calendar_wait(davinci_rtc);
 396         alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
 397
 398         davinci_rtcss_calendar_wait(davinci_rtc);
 399         alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
 400
 401         davinci_rtcss_calendar_wait(davinci_rtc);
 402         day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
 403
 404         davinci_rtcss_calendar_wait(davinci_rtc);
 405         day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
 406
 407         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 408         days |= day1;
 409         days <<= 8;
 410         days |= day0;
 411
 412         if (convertfromdays(days, &alm->time) < 0)
 413                 return -EINVAL;
 414
 415         alm->pending = !!(rtcss_read(davinci_rtc,
 416                           PRTCSS_RTC_CCTRL) &
 417                         PRTCSS_RTC_CCTRL_AIEN);
 418         alm->enabled = alm->pending && device_may_wakeup(dev);
 419
 420         return 0;
 421 }
 422
 423 static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 424 {
 425         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 426         unsigned long flags;
 427         u16 days;
 428
 429         if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
 430             && alm->time.tm_year < 0) {
 431                 struct rtc_time tm;
 432                 unsigned long now, then;
 433
 434                 davinci_rtc_read_time(dev, &tm);
 435                 rtc_tm_to_time(&tm, &now);
 436
 437                 alm->time.tm_mday = tm.tm_mday;
 438                 alm->time.tm_mon = tm.tm_mon;
 439                 alm->time.tm_year = tm.tm_year;
 440                 rtc_tm_to_time(&alm->time, &then);
 441
 442                 if (then < now) {
 443                         rtc_time_to_tm(now + 24 * 60 * 60, &tm);
 444                         alm->time.tm_mday = tm.tm_mday;
 445                         alm->time.tm_mon = tm.tm_mon;
 446                         alm->time.tm_year = tm.tm_year;
 447                 }
 448         }
 449
 450         if (convert2days(&days, &alm->time) < 0)
 451                 return -EINVAL;
 452
 453         spin_lock_irqsave(&davinci_rtc_lock, flags);
 454
 455         davinci_rtcss_calendar_wait(davinci_rtc);
 456         rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
 457
 458         davinci_rtcss_calendar_wait(davinci_rtc);
 459         rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
 460
 461         davinci_rtcss_calendar_wait(davinci_rtc);
 462         rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
 463
 464         davinci_rtcss_calendar_wait(davinci_rtc);
 465         rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
 466
 467         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 468
 469         return 0;
 470 }
 471
 472 static struct rtc_class_ops davinci_rtc_ops = {
 473         .ioctl                  = davinci_rtc_ioctl,
 474         .read_time              = davinci_rtc_read_time,
 475         .set_time               = davinci_rtc_set_time,
 476         .alarm_irq_enable       = davinci_rtc_alarm_irq_enable,
 477         .read_alarm             = davinci_rtc_read_alarm,
 478         .set_alarm              = davinci_rtc_set_alarm,
 479 };
 480
 481 static int __init davinci_rtc_probe(struct platform_device *pdev)
 482 {
 483         struct device *dev = &pdev->dev;
 484         struct davinci_rtc *davinci_rtc;
 485         struct resource *res, *mem;
 486         int ret = 0;
 487
 488         davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
 489         if (!davinci_rtc) {
 490                 dev_dbg(dev, "could not allocate memory for private data\n");
 491                 return -ENOMEM;
 492         }
 493
 494         davinci_rtc->irq = platform_get_irq(pdev, 0);
 495         if (davinci_rtc->irq < 0) {
 496                 dev_err(dev, "no RTC irq\n");
 497                 return davinci_rtc->irq;
 498         }
 499
 500         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 501         if (!res) {
 502                 dev_err(dev, "no mem resource\n");
 503                 return -EINVAL;
 504         }
 505
 506         davinci_rtc->pbase = res->start;
 507         davinci_rtc->base_size = resource_size(res);
 508
 509         mem = devm_request_mem_region(dev, davinci_rtc->pbase,
 510                                 davinci_rtc->base_size, pdev->name);
 511         if (!mem) {
 512                 dev_err(dev, "RTC registers at %08x are not free\n",
 513                         davinci_rtc->pbase);
 514                 return -EBUSY;
 515         }
 516
 517         davinci_rtc->base = devm_ioremap(dev, davinci_rtc->pbase,
 518                                         davinci_rtc->base_size);
 519         if (!davinci_rtc->base) {
 520                 dev_err(dev, "unable to ioremap MEM resource\n");
 521                 return -ENOMEM;
 522         }
 523
 524         platform_set_drvdata(pdev, davinci_rtc);
 525
 526         davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
 527                                     &davinci_rtc_ops, THIS_MODULE);
 528         if (IS_ERR(davinci_rtc->rtc)) {
 529                 dev_err(dev, "unable to register RTC device, err %d\n",
 530                                 ret);
 531                 return PTR_ERR(davinci_rtc->rtc);
 532         }
 533
 534         rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
 535         rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
 536         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
 537
 538         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
 539         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
 540
 541         ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
 542                           0, "davinci_rtc", davinci_rtc);
 543         if (ret < 0) {
 544                 dev_err(dev, "unable to register davinci RTC interrupt\n");
 545                 return ret;
 546         }
 547
 548         /* Enable interrupts */
 549         rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
 550         rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
 551                             PRTCSS_RTC_INTC_EXTENA1);
 552
 553         rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
 554
 555         device_init_wakeup(&pdev->dev, 0);
 556
 557         return 0;
 558 }
 559
 560 static int __exit davinci_rtc_remove(struct platform_device *pdev)
 561 {
 562         struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
 563
 564         device_init_wakeup(&pdev->dev, 0);
 565
 566         rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
 567
 568         return 0;
 569 }
 570
 571 static struct platform_driver davinci_rtc_driver = {
 572         .probe          = davinci_rtc_probe,
 573         .remove         = __exit_p(davinci_rtc_remove),
 574         .driver         = {
 575                 .name = "rtc_davinci",
 576                 .owner = THIS_MODULE,
 577         },
 578 };
 579
 580 module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
 581
 582 MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
 583 MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
 584 MODULE_LICENSE("GPL");