1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Real Time Clock interface for Linux on Atmel AT91RM9200 4 * 5 * Copyright (C) 2002 Rick Bronson 6 * 7 * Converted to RTC class model by Andrew Victor 8 * 9 * Ported to Linux 2.6 by Steven Scholz 10 * Based on s3c2410-rtc.c Simtec Electronics 11 * 12 * Based on sa1100-rtc.c by Nils Faerber 13 * Based on rtc.c by Paul Gortmaker 14 */ 15 16 #include <linux/bcd.h> 17 #include <linux/bitfield.h> 18 #include <linux/clk.h> 19 #include <linux/completion.h> 20 #include <linux/interrupt.h> 21 #include <linux/ioctl.h> 22 #include <linux/io.h> 23 #include <linux/kernel.h> 24 #include <linux/module.h> 25 #include <linux/of_device.h> 26 #include <linux/of.h> 27 #include <linux/platform_device.h> 28 #include <linux/rtc.h> 29 #include <linux/spinlock.h> 30 #include <linux/suspend.h> 31 #include <linux/time.h> 32 #include <linux/uaccess.h> 33 34 #define AT91_RTC_CR 0x00 /* Control Register */ 35 #define AT91_RTC_UPDTIM BIT(0) /* Update Request Time Register */ 36 #define AT91_RTC_UPDCAL BIT(1) /* Update Request Calendar Register */ 37 38 #define AT91_RTC_MR 0x04 /* Mode Register */ 39 #define AT91_RTC_HRMOD BIT(0) /* 12/24 hour mode */ 40 #define AT91_RTC_NEGPPM BIT(4) /* Negative PPM correction */ 41 #define AT91_RTC_CORRECTION GENMASK(14, 8) /* Slow clock correction */ 42 #define AT91_RTC_HIGHPPM BIT(15) /* High PPM correction */ 43 44 #define AT91_RTC_TIMR 0x08 /* Time Register */ 45 #define AT91_RTC_SEC GENMASK(6, 0) /* Current Second */ 46 #define AT91_RTC_MIN GENMASK(14, 8) /* Current Minute */ 47 #define AT91_RTC_HOUR GENMASK(21, 16) /* Current Hour */ 48 #define AT91_RTC_AMPM BIT(22) /* Ante Meridiem Post Meridiem Indicator */ 49 50 #define AT91_RTC_CALR 0x0c /* Calendar Register */ 51 #define AT91_RTC_CENT GENMASK(6, 0) /* Current Century */ 52 #define AT91_RTC_YEAR GENMASK(15, 8) /* Current Year */ 53 #define AT91_RTC_MONTH GENMASK(20, 16) /* Current Month */ 54 #define AT91_RTC_DAY GENMASK(23, 21) /* Current Day */ 55 #define AT91_RTC_DATE GENMASK(29, 24) /* Current Date */ 56 57 #define AT91_RTC_TIMALR 0x10 /* Time Alarm Register */ 58 #define AT91_RTC_SECEN BIT(7) /* Second Alarm Enable */ 59 #define AT91_RTC_MINEN BIT(15) /* Minute Alarm Enable */ 60 #define AT91_RTC_HOUREN BIT(23) /* Hour Alarm Enable */ 61 62 #define AT91_RTC_CALALR 0x14 /* Calendar Alarm Register */ 63 #define AT91_RTC_MTHEN BIT(23) /* Month Alarm Enable */ 64 #define AT91_RTC_DATEEN BIT(31) /* Date Alarm Enable */ 65 66 #define AT91_RTC_SR 0x18 /* Status Register */ 67 #define AT91_RTC_ACKUPD BIT(0) /* Acknowledge for Update */ 68 #define AT91_RTC_ALARM BIT(1) /* Alarm Flag */ 69 #define AT91_RTC_SECEV BIT(2) /* Second Event */ 70 #define AT91_RTC_TIMEV BIT(3) /* Time Event */ 71 #define AT91_RTC_CALEV BIT(4) /* Calendar Event */ 72 73 #define AT91_RTC_SCCR 0x1c /* Status Clear Command Register */ 74 #define AT91_RTC_IER 0x20 /* Interrupt Enable Register */ 75 #define AT91_RTC_IDR 0x24 /* Interrupt Disable Register */ 76 #define AT91_RTC_IMR 0x28 /* Interrupt Mask Register */ 77 78 #define AT91_RTC_VER 0x2c /* Valid Entry Register */ 79 #define AT91_RTC_NVTIM BIT(0) /* Non valid Time */ 80 #define AT91_RTC_NVCAL BIT(1) /* Non valid Calendar */ 81 #define AT91_RTC_NVTIMALR BIT(2) /* Non valid Time Alarm */ 82 #define AT91_RTC_NVCALALR BIT(3) /* Non valid Calendar Alarm */ 83 84 #define AT91_RTC_CORR_DIVIDEND 3906000 85 #define AT91_RTC_CORR_LOW_RATIO 20 86 87 #define at91_rtc_read(field) \ 88 readl_relaxed(at91_rtc_regs + field) 89 #define at91_rtc_write(field, val) \ 90 writel_relaxed((val), at91_rtc_regs + field) 91 92 struct at91_rtc_config { 93 bool use_shadow_imr; 94 bool has_correction; 95 }; 96 97 static const struct at91_rtc_config *at91_rtc_config; 98 static DECLARE_COMPLETION(at91_rtc_updated); 99 static DECLARE_COMPLETION(at91_rtc_upd_rdy); 100 static void __iomem *at91_rtc_regs; 101 static int irq; 102 static DEFINE_SPINLOCK(at91_rtc_lock); 103 static u32 at91_rtc_shadow_imr; 104 static bool suspended; 105 static DEFINE_SPINLOCK(suspended_lock); 106 static unsigned long cached_events; 107 static u32 at91_rtc_imr; 108 static struct clk *sclk; 109 110 static void at91_rtc_write_ier(u32 mask) 111 { 112 unsigned long flags; 113 114 spin_lock_irqsave(&at91_rtc_lock, flags); 115 at91_rtc_shadow_imr |= mask; 116 at91_rtc_write(AT91_RTC_IER, mask); 117 spin_unlock_irqrestore(&at91_rtc_lock, flags); 118 } 119 120 static void at91_rtc_write_idr(u32 mask) 121 { 122 unsigned long flags; 123 124 spin_lock_irqsave(&at91_rtc_lock, flags); 125 at91_rtc_write(AT91_RTC_IDR, mask); 126 /* 127 * Register read back (of any RTC-register) needed to make sure 128 * IDR-register write has reached the peripheral before updating 129 * shadow mask. 130 * 131 * Note that there is still a possibility that the mask is updated 132 * before interrupts have actually been disabled in hardware. The only 133 * way to be certain would be to poll the IMR-register, which is 134 * the very register we are trying to emulate. The register read back 135 * is a reasonable heuristic. 136 */ 137 at91_rtc_read(AT91_RTC_SR); 138 at91_rtc_shadow_imr &= ~mask; 139 spin_unlock_irqrestore(&at91_rtc_lock, flags); 140 } 141 142 static u32 at91_rtc_read_imr(void) 143 { 144 unsigned long flags; 145 u32 mask; 146 147 if (at91_rtc_config->use_shadow_imr) { 148 spin_lock_irqsave(&at91_rtc_lock, flags); 149 mask = at91_rtc_shadow_imr; 150 spin_unlock_irqrestore(&at91_rtc_lock, flags); 151 } else { 152 mask = at91_rtc_read(AT91_RTC_IMR); 153 } 154 155 return mask; 156 } 157 158 /* 159 * Decode time/date into rtc_time structure 160 */ 161 static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg, 162 struct rtc_time *tm) 163 { 164 unsigned int time, date; 165 166 /* must read twice in case it changes */ 167 do { 168 time = at91_rtc_read(timereg); 169 date = at91_rtc_read(calreg); 170 } while ((time != at91_rtc_read(timereg)) || 171 (date != at91_rtc_read(calreg))); 172 173 tm->tm_sec = bcd2bin(FIELD_GET(AT91_RTC_SEC, time)); 174 tm->tm_min = bcd2bin(FIELD_GET(AT91_RTC_MIN, time)); 175 tm->tm_hour = bcd2bin(FIELD_GET(AT91_RTC_HOUR, time)); 176 177 /* 178 * The Calendar Alarm register does not have a field for 179 * the year - so these will return an invalid value. 180 */ 181 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */ 182 tm->tm_year += bcd2bin(FIELD_GET(AT91_RTC_YEAR, date)); /* year */ 183 184 tm->tm_wday = bcd2bin(FIELD_GET(AT91_RTC_DAY, date)) - 1; /* day of the week [0-6], Sunday=0 */ 185 tm->tm_mon = bcd2bin(FIELD_GET(AT91_RTC_MONTH, date)) - 1; 186 tm->tm_mday = bcd2bin(FIELD_GET(AT91_RTC_DATE, date)); 187 } 188 189 /* 190 * Read current time and date in RTC 191 */ 192 static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm) 193 { 194 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm); 195 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); 196 tm->tm_year = tm->tm_year - 1900; 197 198 dev_dbg(dev, "%s(): %ptR\n", __func__, tm); 199 200 return 0; 201 } 202 203 /* 204 * Set current time and date in RTC 205 */ 206 static int at91_rtc_settime(struct device *dev, struct rtc_time *tm) 207 { 208 unsigned long cr; 209 210 dev_dbg(dev, "%s(): %ptR\n", __func__, tm); 211 212 wait_for_completion(&at91_rtc_upd_rdy); 213 214 /* Stop Time/Calendar from counting */ 215 cr = at91_rtc_read(AT91_RTC_CR); 216 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); 217 218 at91_rtc_write_ier(AT91_RTC_ACKUPD); 219 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ 220 at91_rtc_write_idr(AT91_RTC_ACKUPD); 221 222 at91_rtc_write(AT91_RTC_TIMR, 223 FIELD_PREP(AT91_RTC_SEC, bin2bcd(tm->tm_sec)) 224 | FIELD_PREP(AT91_RTC_MIN, bin2bcd(tm->tm_min)) 225 | FIELD_PREP(AT91_RTC_HOUR, bin2bcd(tm->tm_hour))); 226 227 at91_rtc_write(AT91_RTC_CALR, 228 FIELD_PREP(AT91_RTC_CENT, 229 bin2bcd((tm->tm_year + 1900) / 100)) 230 | FIELD_PREP(AT91_RTC_YEAR, bin2bcd(tm->tm_year % 100)) 231 | FIELD_PREP(AT91_RTC_MONTH, bin2bcd(tm->tm_mon + 1)) 232 | FIELD_PREP(AT91_RTC_DAY, bin2bcd(tm->tm_wday + 1)) 233 | FIELD_PREP(AT91_RTC_DATE, bin2bcd(tm->tm_mday))); 234 235 /* Restart Time/Calendar */ 236 cr = at91_rtc_read(AT91_RTC_CR); 237 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_SECEV); 238 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM)); 239 at91_rtc_write_ier(AT91_RTC_SECEV); 240 241 return 0; 242 } 243 244 /* 245 * Read alarm time and date in RTC 246 */ 247 static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm) 248 { 249 struct rtc_time *tm = &alrm->time; 250 251 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm); 252 tm->tm_year = -1; 253 254 alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM) 255 ? 1 : 0; 256 257 dev_dbg(dev, "%s(): %ptR %sabled\n", __func__, tm, 258 alrm->enabled ? "en" : "dis"); 259 260 return 0; 261 } 262 263 /* 264 * Set alarm time and date in RTC 265 */ 266 static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) 267 { 268 struct rtc_time tm = alrm->time; 269 270 at91_rtc_write_idr(AT91_RTC_ALARM); 271 at91_rtc_write(AT91_RTC_TIMALR, 272 FIELD_PREP(AT91_RTC_SEC, bin2bcd(alrm->time.tm_sec)) 273 | FIELD_PREP(AT91_RTC_MIN, bin2bcd(alrm->time.tm_min)) 274 | FIELD_PREP(AT91_RTC_HOUR, bin2bcd(alrm->time.tm_hour)) 275 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN); 276 at91_rtc_write(AT91_RTC_CALALR, 277 FIELD_PREP(AT91_RTC_MONTH, bin2bcd(alrm->time.tm_mon + 1)) 278 | FIELD_PREP(AT91_RTC_DATE, bin2bcd(alrm->time.tm_mday)) 279 | AT91_RTC_DATEEN | AT91_RTC_MTHEN); 280 281 if (alrm->enabled) { 282 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); 283 at91_rtc_write_ier(AT91_RTC_ALARM); 284 } 285 286 dev_dbg(dev, "%s(): %ptR\n", __func__, &tm); 287 288 return 0; 289 } 290 291 static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 292 { 293 dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled); 294 295 if (enabled) { 296 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); 297 at91_rtc_write_ier(AT91_RTC_ALARM); 298 } else 299 at91_rtc_write_idr(AT91_RTC_ALARM); 300 301 return 0; 302 } 303 304 static int at91_rtc_readoffset(struct device *dev, long *offset) 305 { 306 u32 mr = at91_rtc_read(AT91_RTC_MR); 307 long val = FIELD_GET(AT91_RTC_CORRECTION, mr); 308 309 if (!val) { 310 *offset = 0; 311 return 0; 312 } 313 314 val++; 315 316 if (!(mr & AT91_RTC_NEGPPM)) 317 val = -val; 318 319 if (!(mr & AT91_RTC_HIGHPPM)) 320 val *= AT91_RTC_CORR_LOW_RATIO; 321 322 *offset = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, val); 323 324 return 0; 325 } 326 327 static int at91_rtc_setoffset(struct device *dev, long offset) 328 { 329 long corr; 330 u32 mr; 331 332 if (offset > AT91_RTC_CORR_DIVIDEND / 2) 333 return -ERANGE; 334 if (offset < -AT91_RTC_CORR_DIVIDEND / 2) 335 return -ERANGE; 336 337 mr = at91_rtc_read(AT91_RTC_MR); 338 mr &= ~(AT91_RTC_NEGPPM | AT91_RTC_CORRECTION | AT91_RTC_HIGHPPM); 339 340 if (offset > 0) 341 mr |= AT91_RTC_NEGPPM; 342 else 343 offset = -offset; 344 345 /* offset less than 764 ppb, disable correction*/ 346 if (offset < 764) { 347 at91_rtc_write(AT91_RTC_MR, mr & ~AT91_RTC_NEGPPM); 348 349 return 0; 350 } 351 352 /* 353 * 29208 ppb is the perfect cutoff between low range and high range 354 * low range values are never better than high range value after that. 355 */ 356 if (offset < 29208) { 357 corr = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, offset * AT91_RTC_CORR_LOW_RATIO); 358 } else { 359 corr = DIV_ROUND_CLOSEST(AT91_RTC_CORR_DIVIDEND, offset); 360 mr |= AT91_RTC_HIGHPPM; 361 } 362 363 if (corr > 128) 364 corr = 128; 365 366 mr |= FIELD_PREP(AT91_RTC_CORRECTION, corr - 1); 367 368 at91_rtc_write(AT91_RTC_MR, mr); 369 370 return 0; 371 } 372 373 /* 374 * IRQ handler for the RTC 375 */ 376 static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id) 377 { 378 struct platform_device *pdev = dev_id; 379 struct rtc_device *rtc = platform_get_drvdata(pdev); 380 unsigned int rtsr; 381 unsigned long events = 0; 382 int ret = IRQ_NONE; 383 384 spin_lock(&suspended_lock); 385 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr(); 386 if (rtsr) { /* this interrupt is shared! Is it ours? */ 387 if (rtsr & AT91_RTC_ALARM) 388 events |= (RTC_AF | RTC_IRQF); 389 if (rtsr & AT91_RTC_SECEV) { 390 complete(&at91_rtc_upd_rdy); 391 at91_rtc_write_idr(AT91_RTC_SECEV); 392 } 393 if (rtsr & AT91_RTC_ACKUPD) 394 complete(&at91_rtc_updated); 395 396 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */ 397 398 if (!suspended) { 399 rtc_update_irq(rtc, 1, events); 400 401 dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", 402 __func__, events >> 8, events & 0x000000FF); 403 } else { 404 cached_events |= events; 405 at91_rtc_write_idr(at91_rtc_imr); 406 pm_system_wakeup(); 407 } 408 409 ret = IRQ_HANDLED; 410 } 411 spin_unlock(&suspended_lock); 412 413 return ret; 414 } 415 416 static const struct at91_rtc_config at91rm9200_config = { 417 }; 418 419 static const struct at91_rtc_config at91sam9x5_config = { 420 .use_shadow_imr = true, 421 }; 422 423 static const struct at91_rtc_config sama5d4_config = { 424 .has_correction = true, 425 }; 426 427 static const struct of_device_id at91_rtc_dt_ids[] = { 428 { 429 .compatible = "atmel,at91rm9200-rtc", 430 .data = &at91rm9200_config, 431 }, { 432 .compatible = "atmel,at91sam9x5-rtc", 433 .data = &at91sam9x5_config, 434 }, { 435 .compatible = "atmel,sama5d4-rtc", 436 .data = &sama5d4_config, 437 }, { 438 .compatible = "atmel,sama5d2-rtc", 439 .data = &sama5d4_config, 440 }, { 441 .compatible = "microchip,sam9x60-rtc", 442 .data = &sama5d4_config, 443 }, { 444 /* sentinel */ 445 } 446 }; 447 MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids); 448 449 static const struct rtc_class_ops at91_rtc_ops = { 450 .read_time = at91_rtc_readtime, 451 .set_time = at91_rtc_settime, 452 .read_alarm = at91_rtc_readalarm, 453 .set_alarm = at91_rtc_setalarm, 454 .alarm_irq_enable = at91_rtc_alarm_irq_enable, 455 }; 456 457 static const struct rtc_class_ops sama5d4_rtc_ops = { 458 .read_time = at91_rtc_readtime, 459 .set_time = at91_rtc_settime, 460 .read_alarm = at91_rtc_readalarm, 461 .set_alarm = at91_rtc_setalarm, 462 .alarm_irq_enable = at91_rtc_alarm_irq_enable, 463 .set_offset = at91_rtc_setoffset, 464 .read_offset = at91_rtc_readoffset, 465 }; 466 467 /* 468 * Initialize and install RTC driver 469 */ 470 static int __init at91_rtc_probe(struct platform_device *pdev) 471 { 472 struct rtc_device *rtc; 473 struct resource *regs; 474 int ret = 0; 475 476 at91_rtc_config = of_device_get_match_data(&pdev->dev); 477 if (!at91_rtc_config) 478 return -ENODEV; 479 480 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 481 if (!regs) { 482 dev_err(&pdev->dev, "no mmio resource defined\n"); 483 return -ENXIO; 484 } 485 486 irq = platform_get_irq(pdev, 0); 487 if (irq < 0) 488 return -ENXIO; 489 490 at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start, 491 resource_size(regs)); 492 if (!at91_rtc_regs) { 493 dev_err(&pdev->dev, "failed to map registers, aborting.\n"); 494 return -ENOMEM; 495 } 496 497 rtc = devm_rtc_allocate_device(&pdev->dev); 498 if (IS_ERR(rtc)) 499 return PTR_ERR(rtc); 500 platform_set_drvdata(pdev, rtc); 501 502 sclk = devm_clk_get(&pdev->dev, NULL); 503 if (IS_ERR(sclk)) 504 return PTR_ERR(sclk); 505 506 ret = clk_prepare_enable(sclk); 507 if (ret) { 508 dev_err(&pdev->dev, "Could not enable slow clock\n"); 509 return ret; 510 } 511 512 at91_rtc_write(AT91_RTC_CR, 0); 513 at91_rtc_write(AT91_RTC_MR, at91_rtc_read(AT91_RTC_MR) & ~AT91_RTC_HRMOD); 514 515 /* Disable all interrupts */ 516 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | 517 AT91_RTC_SECEV | AT91_RTC_TIMEV | 518 AT91_RTC_CALEV); 519 520 ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt, 521 IRQF_SHARED | IRQF_COND_SUSPEND, 522 "at91_rtc", pdev); 523 if (ret) { 524 dev_err(&pdev->dev, "IRQ %d already in use.\n", irq); 525 goto err_clk; 526 } 527 528 /* cpu init code should really have flagged this device as 529 * being wake-capable; if it didn't, do that here. 530 */ 531 if (!device_can_wakeup(&pdev->dev)) 532 device_init_wakeup(&pdev->dev, 1); 533 534 if (at91_rtc_config->has_correction) 535 rtc->ops = &sama5d4_rtc_ops; 536 else 537 rtc->ops = &at91_rtc_ops; 538 539 rtc->range_min = RTC_TIMESTAMP_BEGIN_1900; 540 rtc->range_max = RTC_TIMESTAMP_END_2099; 541 ret = devm_rtc_register_device(rtc); 542 if (ret) 543 goto err_clk; 544 545 /* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy 546 * completion. 547 */ 548 at91_rtc_write_ier(AT91_RTC_SECEV); 549 550 dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n"); 551 return 0; 552 553 err_clk: 554 clk_disable_unprepare(sclk); 555 556 return ret; 557 } 558 559 /* 560 * Disable and remove the RTC driver 561 */ 562 static int __exit at91_rtc_remove(struct platform_device *pdev) 563 { 564 /* Disable all interrupts */ 565 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | 566 AT91_RTC_SECEV | AT91_RTC_TIMEV | 567 AT91_RTC_CALEV); 568 569 clk_disable_unprepare(sclk); 570 571 return 0; 572 } 573 574 static void at91_rtc_shutdown(struct platform_device *pdev) 575 { 576 /* Disable all interrupts */ 577 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | 578 AT91_RTC_SECEV | AT91_RTC_TIMEV | 579 AT91_RTC_CALEV); 580 } 581 582 #ifdef CONFIG_PM_SLEEP 583 584 /* AT91RM9200 RTC Power management control */ 585 586 static int at91_rtc_suspend(struct device *dev) 587 { 588 /* this IRQ is shared with DBGU and other hardware which isn't 589 * necessarily doing PM like we are... 590 */ 591 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); 592 593 at91_rtc_imr = at91_rtc_read_imr() 594 & (AT91_RTC_ALARM|AT91_RTC_SECEV); 595 if (at91_rtc_imr) { 596 if (device_may_wakeup(dev)) { 597 unsigned long flags; 598 599 enable_irq_wake(irq); 600 601 spin_lock_irqsave(&suspended_lock, flags); 602 suspended = true; 603 spin_unlock_irqrestore(&suspended_lock, flags); 604 } else { 605 at91_rtc_write_idr(at91_rtc_imr); 606 } 607 } 608 return 0; 609 } 610 611 static int at91_rtc_resume(struct device *dev) 612 { 613 struct rtc_device *rtc = dev_get_drvdata(dev); 614 615 if (at91_rtc_imr) { 616 if (device_may_wakeup(dev)) { 617 unsigned long flags; 618 619 spin_lock_irqsave(&suspended_lock, flags); 620 621 if (cached_events) { 622 rtc_update_irq(rtc, 1, cached_events); 623 cached_events = 0; 624 } 625 626 suspended = false; 627 spin_unlock_irqrestore(&suspended_lock, flags); 628 629 disable_irq_wake(irq); 630 } 631 at91_rtc_write_ier(at91_rtc_imr); 632 } 633 return 0; 634 } 635 #endif 636 637 static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume); 638 639 static struct platform_driver at91_rtc_driver = { 640 .remove = __exit_p(at91_rtc_remove), 641 .shutdown = at91_rtc_shutdown, 642 .driver = { 643 .name = "at91_rtc", 644 .pm = &at91_rtc_pm_ops, 645 .of_match_table = of_match_ptr(at91_rtc_dt_ids), 646 }, 647 }; 648 649 module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe); 650 651 MODULE_AUTHOR("Rick Bronson"); 652 MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200"); 653 MODULE_LICENSE("GPL"); 654 MODULE_ALIAS("platform:at91_rtc"); 655