kernel/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         int                             irq;
 123 };
 124
 125 static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
 126                                u32 val, u32 addr)
 127 {
 128         writel(val, davinci_rtc->base + addr);
 129 }
 130
 131 static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
 132 {
 133         return readl(davinci_rtc->base + addr);
 134 }
 135
 136 static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
 137 {
 138         while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
 139                 cpu_relax();
 140 }
 141
 142 static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
 143                                unsigned long val, u8 addr)
 144 {
 145         rtcif_wait(davinci_rtc);
 146
 147         rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
 148         rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
 149
 150         rtcif_wait(davinci_rtc);
 151 }
 152
 153 static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
 154 {
 155         rtcif_wait(davinci_rtc);
 156
 157         rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
 158                     PRTCIF_CTLR);
 159
 160         rtcif_wait(davinci_rtc);
 161
 162         return rtcif_read(davinci_rtc, PRTCIF_LDATA);
 163 }
 164
 165 static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
 166 {
 167         while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
 168                PRTCSS_RTC_CCTRL_CALBUSY)
 169                 cpu_relax();
 170 }
 171
 172 static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
 173 {
 174         struct davinci_rtc *davinci_rtc = class_dev;
 175         unsigned long events = 0;
 176         u32 irq_flg;
 177         u8 alm_irq, tmr_irq;
 178         u8 rtc_ctrl, rtc_cctrl;
 179         int ret = IRQ_NONE;
 180
 181         irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
 182                   PRTCIF_INTFLG_RTCSS;
 183
 184         alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
 185                   PRTCSS_RTC_CCTRL_ALMFLG;
 186
 187         tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
 188                   PRTCSS_RTC_CTRL_TMRFLG;
 189
 190         if (irq_flg) {
 191                 if (alm_irq) {
 192                         events |= RTC_IRQF | RTC_AF;
 193                         rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 194                         rtc_cctrl |=  PRTCSS_RTC_CCTRL_ALMFLG;
 195                         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 196                 } else if (tmr_irq) {
 197                         events |= RTC_IRQF | RTC_PF;
 198                         rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
 199                         rtc_ctrl |=  PRTCSS_RTC_CTRL_TMRFLG;
 200                         rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
 201                 }
 202
 203                 rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
 204                                     PRTCIF_INTFLG);
 205                 rtc_update_irq(davinci_rtc->rtc, 1, events);
 206
 207                 ret = IRQ_HANDLED;
 208         }
 209
 210         return ret;
 211 }
 212
 213 static int
 214 davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 215 {
 216         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 217         u8 rtc_ctrl;
 218         unsigned long flags;
 219         int ret = 0;
 220
 221         spin_lock_irqsave(&davinci_rtc_lock, flags);
 222
 223         rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
 224
 225         switch (cmd) {
 226         case RTC_WIE_ON:
 227                 rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
 228                 break;
 229         case RTC_WIE_OFF:
 230                 rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
 231                 break;
 232         default:
 233                 ret = -ENOIOCTLCMD;
 234         }
 235
 236         rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
 237
 238         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 239
 240         return ret;
 241 }
 242
 243 static int convertfromdays(u16 days, struct rtc_time *tm)
 244 {
 245         int tmp_days, year, mon;
 246
 247         for (year = 2000;; year++) {
 248                 tmp_days = rtc_year_days(1, 12, year);
 249                 if (days >= tmp_days)
 250                         days -= tmp_days;
 251                 else {
 252                         for (mon = 0;; mon++) {
 253                                 tmp_days = rtc_month_days(mon, year);
 254                                 if (days >= tmp_days) {
 255                                         days -= tmp_days;
 256                                 } else {
 257                                         tm->tm_year = year - 1900;
 258                                         tm->tm_mon = mon;
 259                                         tm->tm_mday = days + 1;
 260                                         break;
 261                                 }
 262                         }
 263                         break;
 264                 }
 265         }
 266         return 0;
 267 }
 268
 269 static int convert2days(u16 *days, struct rtc_time *tm)
 270 {
 271         int i;
 272         *days = 0;
 273
 274         /* epoch == 1900 */
 275         if (tm->tm_year < 100 || tm->tm_year > 199)
 276                 return -EINVAL;
 277
 278         for (i = 2000; i < 1900 + tm->tm_year; i++)
 279                 *days += rtc_year_days(1, 12, i);
 280
 281         *days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
 282
 283         return 0;
 284 }
 285
 286 static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
 287 {
 288         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 289         u16 days = 0;
 290         u8 day0, day1;
 291         unsigned long flags;
 292
 293         spin_lock_irqsave(&davinci_rtc_lock, flags);
 294
 295         davinci_rtcss_calendar_wait(davinci_rtc);
 296         tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
 297
 298         davinci_rtcss_calendar_wait(davinci_rtc);
 299         tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
 300
 301         davinci_rtcss_calendar_wait(davinci_rtc);
 302         tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
 303
 304         davinci_rtcss_calendar_wait(davinci_rtc);
 305         day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
 306
 307         davinci_rtcss_calendar_wait(davinci_rtc);
 308         day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
 309
 310         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 311
 312         days |= day1;
 313         days <<= 8;
 314         days |= day0;
 315
 316         if (convertfromdays(days, tm) < 0)
 317                 return -EINVAL;
 318
 319         return 0;
 320 }
 321
 322 static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
 323 {
 324         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 325         u16 days;
 326         u8 rtc_cctrl;
 327         unsigned long flags;
 328
 329         if (convert2days(&days, tm) < 0)
 330                 return -EINVAL;
 331
 332         spin_lock_irqsave(&davinci_rtc_lock, flags);
 333
 334         davinci_rtcss_calendar_wait(davinci_rtc);
 335         rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
 336
 337         davinci_rtcss_calendar_wait(davinci_rtc);
 338         rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
 339
 340         davinci_rtcss_calendar_wait(davinci_rtc);
 341         rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
 342
 343         davinci_rtcss_calendar_wait(davinci_rtc);
 344         rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
 345
 346         davinci_rtcss_calendar_wait(davinci_rtc);
 347         rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
 348
 349         rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 350         rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
 351         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 352
 353         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 354
 355         return 0;
 356 }
 357
 358 static int davinci_rtc_alarm_irq_enable(struct device *dev,
 359                                         unsigned int enabled)
 360 {
 361         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 362         unsigned long flags;
 363         u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
 364
 365         spin_lock_irqsave(&davinci_rtc_lock, flags);
 366
 367         if (enabled)
 368                 rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
 369                              PRTCSS_RTC_CCTRL_HAEN |
 370                              PRTCSS_RTC_CCTRL_MAEN |
 371                              PRTCSS_RTC_CCTRL_ALMFLG |
 372                              PRTCSS_RTC_CCTRL_AIEN;
 373         else
 374                 rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
 375
 376         davinci_rtcss_calendar_wait(davinci_rtc);
 377         rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
 378
 379         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 380
 381         return 0;
 382 }
 383
 384 static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 385 {
 386         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 387         u16 days = 0;
 388         u8 day0, day1;
 389         unsigned long flags;
 390
 391         spin_lock_irqsave(&davinci_rtc_lock, flags);
 392
 393         davinci_rtcss_calendar_wait(davinci_rtc);
 394         alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
 395
 396         davinci_rtcss_calendar_wait(davinci_rtc);
 397         alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
 398
 399         davinci_rtcss_calendar_wait(davinci_rtc);
 400         day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
 401
 402         davinci_rtcss_calendar_wait(davinci_rtc);
 403         day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
 404
 405         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 406         days |= day1;
 407         days <<= 8;
 408         days |= day0;
 409
 410         if (convertfromdays(days, &alm->time) < 0)
 411                 return -EINVAL;
 412
 413         alm->pending = !!(rtcss_read(davinci_rtc,
 414                           PRTCSS_RTC_CCTRL) &
 415                         PRTCSS_RTC_CCTRL_AIEN);
 416         alm->enabled = alm->pending && device_may_wakeup(dev);
 417
 418         return 0;
 419 }
 420
 421 static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 422 {
 423         struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
 424         unsigned long flags;
 425         u16 days;
 426
 427         if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
 428             && alm->time.tm_year < 0) {
 429                 struct rtc_time tm;
 430                 unsigned long now, then;
 431
 432                 davinci_rtc_read_time(dev, &tm);
 433                 rtc_tm_to_time(&tm, &now);
 434
 435                 alm->time.tm_mday = tm.tm_mday;
 436                 alm->time.tm_mon = tm.tm_mon;
 437                 alm->time.tm_year = tm.tm_year;
 438                 rtc_tm_to_time(&alm->time, &then);
 439
 440                 if (then < now) {
 441                         rtc_time_to_tm(now + 24 * 60 * 60, &tm);
 442                         alm->time.tm_mday = tm.tm_mday;
 443                         alm->time.tm_mon = tm.tm_mon;
 444                         alm->time.tm_year = tm.tm_year;
 445                 }
 446         }
 447
 448         if (convert2days(&days, &alm->time) < 0)
 449                 return -EINVAL;
 450
 451         spin_lock_irqsave(&davinci_rtc_lock, flags);
 452
 453         davinci_rtcss_calendar_wait(davinci_rtc);
 454         rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
 455
 456         davinci_rtcss_calendar_wait(davinci_rtc);
 457         rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
 458
 459         davinci_rtcss_calendar_wait(davinci_rtc);
 460         rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
 461
 462         davinci_rtcss_calendar_wait(davinci_rtc);
 463         rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
 464
 465         spin_unlock_irqrestore(&davinci_rtc_lock, flags);
 466
 467         return 0;
 468 }
 469
 470 static struct rtc_class_ops davinci_rtc_ops = {
 471         .ioctl                  = davinci_rtc_ioctl,
 472         .read_time              = davinci_rtc_read_time,
 473         .set_time               = davinci_rtc_set_time,
 474         .alarm_irq_enable       = davinci_rtc_alarm_irq_enable,
 475         .read_alarm             = davinci_rtc_read_alarm,
 476         .set_alarm              = davinci_rtc_set_alarm,
 477 };
 478
 479 static int __init davinci_rtc_probe(struct platform_device *pdev)
 480 {
 481         struct device *dev = &pdev->dev;
 482         struct davinci_rtc *davinci_rtc;
 483         struct resource *res;
 484         int ret = 0;
 485
 486         davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
 487         if (!davinci_rtc)
 488                 return -ENOMEM;
 489
 490         davinci_rtc->irq = platform_get_irq(pdev, 0);
 491         if (davinci_rtc->irq < 0) {
 492                 dev_err(dev, "no RTC irq\n");
 493                 return davinci_rtc->irq;
 494         }
 495
 496         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 497         davinci_rtc->base = devm_ioremap_resource(dev, res);
 498         if (IS_ERR(davinci_rtc->base))
 499                 return PTR_ERR(davinci_rtc->base);
 500
 501         platform_set_drvdata(pdev, davinci_rtc);
 502
 503         davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
 504                                     &davinci_rtc_ops, THIS_MODULE);
 505         if (IS_ERR(davinci_rtc->rtc)) {
 506                 dev_err(dev, "unable to register RTC device, err %d\n",
 507                                 ret);
 508                 return PTR_ERR(davinci_rtc->rtc);
 509         }
 510
 511         rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
 512         rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
 513         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
 514
 515         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
 516         rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
 517
 518         ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
 519                           0, "davinci_rtc", davinci_rtc);
 520         if (ret < 0) {
 521                 dev_err(dev, "unable to register davinci RTC interrupt\n");
 522                 return ret;
 523         }
 524
 525         /* Enable interrupts */
 526         rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
 527         rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
 528                             PRTCSS_RTC_INTC_EXTENA1);
 529
 530         rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
 531
 532         device_init_wakeup(&pdev->dev, 0);
 533
 534         return 0;
 535 }
 536
 537 static int __exit davinci_rtc_remove(struct platform_device *pdev)
 538 {
 539         struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
 540
 541         device_init_wakeup(&pdev->dev, 0);
 542
 543         rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
 544
 545         return 0;
 546 }
 547
 548 static struct platform_driver davinci_rtc_driver = {
 549         .probe          = davinci_rtc_probe,
 550         .remove         = __exit_p(davinci_rtc_remove),
 551         .driver         = {
 552                 .name = "rtc_davinci",
 553         },
 554 };
 555
 556 module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
 557
 558 MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
 559 MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
 560 MODULE_LICENSE("GPL");