1 /* drivers/rtc/rtc-s3c.c 2 * 3 * Copyright (c) 2010 Samsung Electronics Co., Ltd. 4 * http://www.samsung.com/ 5 * 6 * Copyright (c) 2004,2006 Simtec Electronics 7 * Ben Dooks, <ben@simtec.co.uk> 8 * http://armlinux.simtec.co.uk/ 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 * 14 * S3C2410/S3C2440/S3C24XX Internal RTC Driver 15 */ 16 17 #include <linux/module.h> 18 #include <linux/fs.h> 19 #include <linux/string.h> 20 #include <linux/init.h> 21 #include <linux/platform_device.h> 22 #include <linux/interrupt.h> 23 #include <linux/rtc.h> 24 #include <linux/bcd.h> 25 #include <linux/clk.h> 26 #include <linux/log2.h> 27 #include <linux/slab.h> 28 29 #include <mach/hardware.h> 30 #include <asm/uaccess.h> 31 #include <asm/io.h> 32 #include <asm/irq.h> 33 #include <plat/regs-rtc.h> 34 35 enum s3c_cpu_type { 36 TYPE_S3C2410, 37 TYPE_S3C64XX, 38 }; 39 40 /* I have yet to find an S3C implementation with more than one 41 * of these rtc blocks in */ 42 43 static struct resource *s3c_rtc_mem; 44 45 static struct clk *rtc_clk; 46 static void __iomem *s3c_rtc_base; 47 static int s3c_rtc_alarmno = NO_IRQ; 48 static int s3c_rtc_tickno = NO_IRQ; 49 static enum s3c_cpu_type s3c_rtc_cpu_type; 50 51 static DEFINE_SPINLOCK(s3c_rtc_pie_lock); 52 53 /* IRQ Handlers */ 54 55 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id) 56 { 57 struct rtc_device *rdev = id; 58 59 rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF); 60 61 if (s3c_rtc_cpu_type == TYPE_S3C64XX) 62 writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP); 63 64 return IRQ_HANDLED; 65 } 66 67 static irqreturn_t s3c_rtc_tickirq(int irq, void *id) 68 { 69 struct rtc_device *rdev = id; 70 71 rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF); 72 73 if (s3c_rtc_cpu_type == TYPE_S3C64XX) 74 writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP); 75 76 return IRQ_HANDLED; 77 } 78 79 /* Update control registers */ 80 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled) 81 { 82 unsigned int tmp; 83 84 pr_debug("%s: aie=%d\n", __func__, enabled); 85 86 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN; 87 88 if (enabled) 89 tmp |= S3C2410_RTCALM_ALMEN; 90 91 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM); 92 93 return 0; 94 } 95 96 static int s3c_rtc_setfreq(struct device *dev, int freq) 97 { 98 struct platform_device *pdev = to_platform_device(dev); 99 struct rtc_device *rtc_dev = platform_get_drvdata(pdev); 100 unsigned int tmp = 0; 101 102 if (!is_power_of_2(freq)) 103 return -EINVAL; 104 105 spin_lock_irq(&s3c_rtc_pie_lock); 106 107 if (s3c_rtc_cpu_type == TYPE_S3C2410) { 108 tmp = readb(s3c_rtc_base + S3C2410_TICNT); 109 tmp &= S3C2410_TICNT_ENABLE; 110 } 111 112 tmp |= (rtc_dev->max_user_freq / freq)-1; 113 114 writel(tmp, s3c_rtc_base + S3C2410_TICNT); 115 spin_unlock_irq(&s3c_rtc_pie_lock); 116 117 return 0; 118 } 119 120 /* Time read/write */ 121 122 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) 123 { 124 unsigned int have_retried = 0; 125 void __iomem *base = s3c_rtc_base; 126 127 retry_get_time: 128 rtc_tm->tm_min = readb(base + S3C2410_RTCMIN); 129 rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR); 130 rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE); 131 rtc_tm->tm_mon = readb(base + S3C2410_RTCMON); 132 rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR); 133 rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC); 134 135 /* the only way to work out wether the system was mid-update 136 * when we read it is to check the second counter, and if it 137 * is zero, then we re-try the entire read 138 */ 139 140 if (rtc_tm->tm_sec == 0 && !have_retried) { 141 have_retried = 1; 142 goto retry_get_time; 143 } 144 145 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n", 146 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday, 147 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec); 148 149 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec); 150 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min); 151 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour); 152 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday); 153 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon); 154 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year); 155 156 rtc_tm->tm_year += 100; 157 rtc_tm->tm_mon -= 1; 158 159 return rtc_valid_tm(rtc_tm); 160 } 161 162 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm) 163 { 164 void __iomem *base = s3c_rtc_base; 165 int year = tm->tm_year - 100; 166 167 pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n", 168 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, 169 tm->tm_hour, tm->tm_min, tm->tm_sec); 170 171 /* we get around y2k by simply not supporting it */ 172 173 if (year < 0 || year >= 100) { 174 dev_err(dev, "rtc only supports 100 years\n"); 175 return -EINVAL; 176 } 177 178 writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC); 179 writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN); 180 writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR); 181 writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE); 182 writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON); 183 writeb(bin2bcd(year), base + S3C2410_RTCYEAR); 184 185 return 0; 186 } 187 188 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm) 189 { 190 struct rtc_time *alm_tm = &alrm->time; 191 void __iomem *base = s3c_rtc_base; 192 unsigned int alm_en; 193 194 alm_tm->tm_sec = readb(base + S3C2410_ALMSEC); 195 alm_tm->tm_min = readb(base + S3C2410_ALMMIN); 196 alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR); 197 alm_tm->tm_mon = readb(base + S3C2410_ALMMON); 198 alm_tm->tm_mday = readb(base + S3C2410_ALMDATE); 199 alm_tm->tm_year = readb(base + S3C2410_ALMYEAR); 200 201 alm_en = readb(base + S3C2410_RTCALM); 202 203 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0; 204 205 pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n", 206 alm_en, 207 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday, 208 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec); 209 210 211 /* decode the alarm enable field */ 212 213 if (alm_en & S3C2410_RTCALM_SECEN) 214 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec); 215 else 216 alm_tm->tm_sec = -1; 217 218 if (alm_en & S3C2410_RTCALM_MINEN) 219 alm_tm->tm_min = bcd2bin(alm_tm->tm_min); 220 else 221 alm_tm->tm_min = -1; 222 223 if (alm_en & S3C2410_RTCALM_HOUREN) 224 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour); 225 else 226 alm_tm->tm_hour = -1; 227 228 if (alm_en & S3C2410_RTCALM_DAYEN) 229 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday); 230 else 231 alm_tm->tm_mday = -1; 232 233 if (alm_en & S3C2410_RTCALM_MONEN) { 234 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon); 235 alm_tm->tm_mon -= 1; 236 } else { 237 alm_tm->tm_mon = -1; 238 } 239 240 if (alm_en & S3C2410_RTCALM_YEAREN) 241 alm_tm->tm_year = bcd2bin(alm_tm->tm_year); 242 else 243 alm_tm->tm_year = -1; 244 245 return 0; 246 } 247 248 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) 249 { 250 struct rtc_time *tm = &alrm->time; 251 void __iomem *base = s3c_rtc_base; 252 unsigned int alrm_en; 253 254 pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n", 255 alrm->enabled, 256 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, 257 tm->tm_hour, tm->tm_min, tm->tm_sec); 258 259 260 alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN; 261 writeb(0x00, base + S3C2410_RTCALM); 262 263 if (tm->tm_sec < 60 && tm->tm_sec >= 0) { 264 alrm_en |= S3C2410_RTCALM_SECEN; 265 writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC); 266 } 267 268 if (tm->tm_min < 60 && tm->tm_min >= 0) { 269 alrm_en |= S3C2410_RTCALM_MINEN; 270 writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN); 271 } 272 273 if (tm->tm_hour < 24 && tm->tm_hour >= 0) { 274 alrm_en |= S3C2410_RTCALM_HOUREN; 275 writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR); 276 } 277 278 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en); 279 280 writeb(alrm_en, base + S3C2410_RTCALM); 281 282 s3c_rtc_setaie(dev, alrm->enabled); 283 284 return 0; 285 } 286 287 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq) 288 { 289 unsigned int ticnt; 290 291 if (s3c_rtc_cpu_type == TYPE_S3C64XX) { 292 ticnt = readw(s3c_rtc_base + S3C2410_RTCCON); 293 ticnt &= S3C64XX_RTCCON_TICEN; 294 } else { 295 ticnt = readb(s3c_rtc_base + S3C2410_TICNT); 296 ticnt &= S3C2410_TICNT_ENABLE; 297 } 298 299 seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no"); 300 return 0; 301 } 302 303 static int s3c_rtc_open(struct device *dev) 304 { 305 struct platform_device *pdev = to_platform_device(dev); 306 struct rtc_device *rtc_dev = platform_get_drvdata(pdev); 307 int ret; 308 309 ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq, 310 IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev); 311 312 if (ret) { 313 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret); 314 return ret; 315 } 316 317 ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq, 318 IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev); 319 320 if (ret) { 321 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret); 322 goto tick_err; 323 } 324 325 return ret; 326 327 tick_err: 328 free_irq(s3c_rtc_alarmno, rtc_dev); 329 return ret; 330 } 331 332 static void s3c_rtc_release(struct device *dev) 333 { 334 struct platform_device *pdev = to_platform_device(dev); 335 struct rtc_device *rtc_dev = platform_get_drvdata(pdev); 336 337 /* do not clear AIE here, it may be needed for wake */ 338 339 free_irq(s3c_rtc_alarmno, rtc_dev); 340 free_irq(s3c_rtc_tickno, rtc_dev); 341 } 342 343 static const struct rtc_class_ops s3c_rtcops = { 344 .open = s3c_rtc_open, 345 .release = s3c_rtc_release, 346 .read_time = s3c_rtc_gettime, 347 .set_time = s3c_rtc_settime, 348 .read_alarm = s3c_rtc_getalarm, 349 .set_alarm = s3c_rtc_setalarm, 350 .proc = s3c_rtc_proc, 351 .alarm_irq_enable = s3c_rtc_setaie, 352 }; 353 354 static void s3c_rtc_enable(struct platform_device *pdev, int en) 355 { 356 void __iomem *base = s3c_rtc_base; 357 unsigned int tmp; 358 359 if (s3c_rtc_base == NULL) 360 return; 361 362 if (!en) { 363 tmp = readw(base + S3C2410_RTCCON); 364 if (s3c_rtc_cpu_type == TYPE_S3C64XX) 365 tmp &= ~S3C64XX_RTCCON_TICEN; 366 tmp &= ~S3C2410_RTCCON_RTCEN; 367 writew(tmp, base + S3C2410_RTCCON); 368 369 if (s3c_rtc_cpu_type == TYPE_S3C2410) { 370 tmp = readb(base + S3C2410_TICNT); 371 tmp &= ~S3C2410_TICNT_ENABLE; 372 writeb(tmp, base + S3C2410_TICNT); 373 } 374 } else { 375 /* re-enable the device, and check it is ok */ 376 377 if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) { 378 dev_info(&pdev->dev, "rtc disabled, re-enabling\n"); 379 380 tmp = readw(base + S3C2410_RTCCON); 381 writew(tmp | S3C2410_RTCCON_RTCEN, 382 base + S3C2410_RTCCON); 383 } 384 385 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) { 386 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n"); 387 388 tmp = readw(base + S3C2410_RTCCON); 389 writew(tmp & ~S3C2410_RTCCON_CNTSEL, 390 base + S3C2410_RTCCON); 391 } 392 393 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) { 394 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n"); 395 396 tmp = readw(base + S3C2410_RTCCON); 397 writew(tmp & ~S3C2410_RTCCON_CLKRST, 398 base + S3C2410_RTCCON); 399 } 400 } 401 } 402 403 static int __devexit s3c_rtc_remove(struct platform_device *dev) 404 { 405 struct rtc_device *rtc = platform_get_drvdata(dev); 406 407 platform_set_drvdata(dev, NULL); 408 rtc_device_unregister(rtc); 409 410 s3c_rtc_setaie(&dev->dev, 0); 411 412 clk_disable(rtc_clk); 413 clk_put(rtc_clk); 414 rtc_clk = NULL; 415 416 iounmap(s3c_rtc_base); 417 release_resource(s3c_rtc_mem); 418 kfree(s3c_rtc_mem); 419 420 return 0; 421 } 422 423 static int __devinit s3c_rtc_probe(struct platform_device *pdev) 424 { 425 struct rtc_device *rtc; 426 struct rtc_time rtc_tm; 427 struct resource *res; 428 int ret; 429 430 pr_debug("%s: probe=%p\n", __func__, pdev); 431 432 /* find the IRQs */ 433 434 s3c_rtc_tickno = platform_get_irq(pdev, 1); 435 if (s3c_rtc_tickno < 0) { 436 dev_err(&pdev->dev, "no irq for rtc tick\n"); 437 return -ENOENT; 438 } 439 440 s3c_rtc_alarmno = platform_get_irq(pdev, 0); 441 if (s3c_rtc_alarmno < 0) { 442 dev_err(&pdev->dev, "no irq for alarm\n"); 443 return -ENOENT; 444 } 445 446 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n", 447 s3c_rtc_tickno, s3c_rtc_alarmno); 448 449 /* get the memory region */ 450 451 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 452 if (res == NULL) { 453 dev_err(&pdev->dev, "failed to get memory region resource\n"); 454 return -ENOENT; 455 } 456 457 s3c_rtc_mem = request_mem_region(res->start, 458 res->end-res->start+1, 459 pdev->name); 460 461 if (s3c_rtc_mem == NULL) { 462 dev_err(&pdev->dev, "failed to reserve memory region\n"); 463 ret = -ENOENT; 464 goto err_nores; 465 } 466 467 s3c_rtc_base = ioremap(res->start, res->end - res->start + 1); 468 if (s3c_rtc_base == NULL) { 469 dev_err(&pdev->dev, "failed ioremap()\n"); 470 ret = -EINVAL; 471 goto err_nomap; 472 } 473 474 rtc_clk = clk_get(&pdev->dev, "rtc"); 475 if (IS_ERR(rtc_clk)) { 476 dev_err(&pdev->dev, "failed to find rtc clock source\n"); 477 ret = PTR_ERR(rtc_clk); 478 rtc_clk = NULL; 479 goto err_clk; 480 } 481 482 clk_enable(rtc_clk); 483 484 /* check to see if everything is setup correctly */ 485 486 s3c_rtc_enable(pdev, 1); 487 488 pr_debug("s3c2410_rtc: RTCCON=%02x\n", 489 readw(s3c_rtc_base + S3C2410_RTCCON)); 490 491 device_init_wakeup(&pdev->dev, 1); 492 493 /* register RTC and exit */ 494 495 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops, 496 THIS_MODULE); 497 498 if (IS_ERR(rtc)) { 499 dev_err(&pdev->dev, "cannot attach rtc\n"); 500 ret = PTR_ERR(rtc); 501 goto err_nortc; 502 } 503 504 s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data; 505 506 /* Check RTC Time */ 507 508 s3c_rtc_gettime(NULL, &rtc_tm); 509 510 if (rtc_valid_tm(&rtc_tm)) { 511 rtc_tm.tm_year = 100; 512 rtc_tm.tm_mon = 0; 513 rtc_tm.tm_mday = 1; 514 rtc_tm.tm_hour = 0; 515 rtc_tm.tm_min = 0; 516 rtc_tm.tm_sec = 0; 517 518 s3c_rtc_settime(NULL, &rtc_tm); 519 520 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n"); 521 } 522 523 if (s3c_rtc_cpu_type == TYPE_S3C64XX) 524 rtc->max_user_freq = 32768; 525 else 526 rtc->max_user_freq = 128; 527 528 platform_set_drvdata(pdev, rtc); 529 530 s3c_rtc_setfreq(&pdev->dev, 1); 531 532 return 0; 533 534 err_nortc: 535 s3c_rtc_enable(pdev, 0); 536 clk_disable(rtc_clk); 537 clk_put(rtc_clk); 538 539 err_clk: 540 iounmap(s3c_rtc_base); 541 542 err_nomap: 543 release_resource(s3c_rtc_mem); 544 545 err_nores: 546 return ret; 547 } 548 549 #ifdef CONFIG_PM 550 551 /* RTC Power management control */ 552 553 static int ticnt_save, ticnt_en_save; 554 555 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state) 556 { 557 /* save TICNT for anyone using periodic interrupts */ 558 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT); 559 if (s3c_rtc_cpu_type == TYPE_S3C64XX) { 560 ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON); 561 ticnt_en_save &= S3C64XX_RTCCON_TICEN; 562 } 563 s3c_rtc_enable(pdev, 0); 564 565 if (device_may_wakeup(&pdev->dev)) 566 enable_irq_wake(s3c_rtc_alarmno); 567 568 return 0; 569 } 570 571 static int s3c_rtc_resume(struct platform_device *pdev) 572 { 573 unsigned int tmp; 574 575 s3c_rtc_enable(pdev, 1); 576 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT); 577 if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) { 578 tmp = readw(s3c_rtc_base + S3C2410_RTCCON); 579 writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON); 580 } 581 582 if (device_may_wakeup(&pdev->dev)) 583 disable_irq_wake(s3c_rtc_alarmno); 584 585 return 0; 586 } 587 #else 588 #define s3c_rtc_suspend NULL 589 #define s3c_rtc_resume NULL 590 #endif 591 592 static struct platform_device_id s3c_rtc_driver_ids[] = { 593 { 594 .name = "s3c2410-rtc", 595 .driver_data = TYPE_S3C2410, 596 }, { 597 .name = "s3c64xx-rtc", 598 .driver_data = TYPE_S3C64XX, 599 }, 600 { } 601 }; 602 603 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids); 604 605 static struct platform_driver s3c_rtc_driver = { 606 .probe = s3c_rtc_probe, 607 .remove = __devexit_p(s3c_rtc_remove), 608 .suspend = s3c_rtc_suspend, 609 .resume = s3c_rtc_resume, 610 .id_table = s3c_rtc_driver_ids, 611 .driver = { 612 .name = "s3c-rtc", 613 .owner = THIS_MODULE, 614 }, 615 }; 616 617 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n"; 618 619 static int __init s3c_rtc_init(void) 620 { 621 printk(banner); 622 return platform_driver_register(&s3c_rtc_driver); 623 } 624 625 static void __exit s3c_rtc_exit(void) 626 { 627 platform_driver_unregister(&s3c_rtc_driver); 628 } 629 630 module_init(s3c_rtc_init); 631 module_exit(s3c_rtc_exit); 632 633 MODULE_DESCRIPTION("Samsung S3C RTC Driver"); 634 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); 635 MODULE_LICENSE("GPL"); 636 MODULE_ALIAS("platform:s3c2410-rtc"); 637