1 /* drivers/rtc/rtc-s3c.c
3 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
4 * http://www.samsung.com/
6 * Copyright (c) 2004,2006 Simtec Electronics
7 * Ben Dooks, <ben@simtec.co.uk>
8 * http://armlinux.simtec.co.uk/
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.
14 * S3C2410/S3C2440/S3C24XX Internal RTC Driver
17 #include <linux/module.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>
29 #include <linux/uaccess.h>
32 #include <mach/hardware.h>
34 #include <plat/regs-rtc.h>
43 struct s3c_rtc_drv_data {
47 /* I have yet to find an S3C implementation with more than one
48 * of these rtc blocks in */
50 static struct clk *rtc_clk;
51 static void __iomem *s3c_rtc_base;
52 static int s3c_rtc_alarmno = NO_IRQ;
53 static int s3c_rtc_tickno = NO_IRQ;
55 static enum s3c_cpu_type s3c_rtc_cpu_type;
57 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
59 static void s3c_rtc_alarm_clk_enable(bool enable)
61 static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock);
62 static bool alarm_clk_enabled;
63 unsigned long irq_flags;
65 spin_lock_irqsave(&s3c_rtc_alarm_clk_lock, irq_flags);
67 if (!alarm_clk_enabled) {
69 alarm_clk_enabled = true;
72 if (alarm_clk_enabled) {
74 alarm_clk_enabled = false;
77 spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock, irq_flags);
82 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
84 struct rtc_device *rdev = id;
87 rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
89 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
90 writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
94 s3c_rtc_alarm_clk_enable(false);
99 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
101 struct rtc_device *rdev = id;
104 rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
106 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
107 writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
109 clk_disable(rtc_clk);
113 /* Update control registers */
114 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
118 pr_debug("%s: aie=%d\n", __func__, enabled);
121 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
124 tmp |= S3C2410_RTCALM_ALMEN;
126 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
127 clk_disable(rtc_clk);
129 s3c_rtc_alarm_clk_enable(enabled);
134 static int s3c_rtc_setfreq(struct device *dev, int freq)
136 struct platform_device *pdev = to_platform_device(dev);
137 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
138 unsigned int tmp = 0;
141 if (!is_power_of_2(freq))
145 spin_lock_irq(&s3c_rtc_pie_lock);
147 if (s3c_rtc_cpu_type != TYPE_S3C64XX) {
148 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
149 tmp &= S3C2410_TICNT_ENABLE;
152 val = (rtc_dev->max_user_freq / freq) - 1;
154 if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) {
155 tmp |= S3C2443_TICNT_PART(val);
156 writel(S3C2443_TICNT1_PART(val), s3c_rtc_base + S3C2443_TICNT1);
158 if (s3c_rtc_cpu_type == TYPE_S3C2416)
159 writel(S3C2416_TICNT2_PART(val), s3c_rtc_base + S3C2416_TICNT2);
164 writel(tmp, s3c_rtc_base + S3C2410_TICNT);
165 spin_unlock_irq(&s3c_rtc_pie_lock);
166 clk_disable(rtc_clk);
171 /* Time read/write */
173 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
175 unsigned int have_retried = 0;
176 void __iomem *base = s3c_rtc_base;
180 rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
181 rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
182 rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
183 rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
184 rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
185 rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
187 /* the only way to work out whether the system was mid-update
188 * when we read it is to check the second counter, and if it
189 * is zero, then we re-try the entire read
192 if (rtc_tm->tm_sec == 0 && !have_retried) {
197 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
198 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
199 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
200 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
201 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
202 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
204 rtc_tm->tm_year += 100;
206 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
207 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
208 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
212 clk_disable(rtc_clk);
213 return rtc_valid_tm(rtc_tm);
216 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
218 void __iomem *base = s3c_rtc_base;
219 int year = tm->tm_year - 100;
221 pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
222 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
223 tm->tm_hour, tm->tm_min, tm->tm_sec);
225 /* we get around y2k by simply not supporting it */
227 if (year < 0 || year >= 100) {
228 dev_err(dev, "rtc only supports 100 years\n");
233 writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC);
234 writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN);
235 writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR);
236 writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
237 writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
238 writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
239 clk_disable(rtc_clk);
244 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
246 struct rtc_time *alm_tm = &alrm->time;
247 void __iomem *base = s3c_rtc_base;
251 alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
252 alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
253 alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
254 alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
255 alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
256 alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
258 alm_en = readb(base + S3C2410_RTCALM);
260 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
262 pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
264 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
265 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
268 /* decode the alarm enable field */
270 if (alm_en & S3C2410_RTCALM_SECEN)
271 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
275 if (alm_en & S3C2410_RTCALM_MINEN)
276 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
280 if (alm_en & S3C2410_RTCALM_HOUREN)
281 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
283 alm_tm->tm_hour = -1;
285 if (alm_en & S3C2410_RTCALM_DAYEN)
286 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
288 alm_tm->tm_mday = -1;
290 if (alm_en & S3C2410_RTCALM_MONEN) {
291 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
297 if (alm_en & S3C2410_RTCALM_YEAREN)
298 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
300 alm_tm->tm_year = -1;
302 clk_disable(rtc_clk);
306 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
308 struct rtc_time *tm = &alrm->time;
309 void __iomem *base = s3c_rtc_base;
310 unsigned int alrm_en;
313 pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
315 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
316 tm->tm_hour, tm->tm_min, tm->tm_sec);
318 alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
319 writeb(0x00, base + S3C2410_RTCALM);
321 if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
322 alrm_en |= S3C2410_RTCALM_SECEN;
323 writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
326 if (tm->tm_min < 60 && tm->tm_min >= 0) {
327 alrm_en |= S3C2410_RTCALM_MINEN;
328 writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
331 if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
332 alrm_en |= S3C2410_RTCALM_HOUREN;
333 writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
336 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
338 writeb(alrm_en, base + S3C2410_RTCALM);
340 s3c_rtc_setaie(dev, alrm->enabled);
342 clk_disable(rtc_clk);
346 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
351 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
352 ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
353 ticnt &= S3C64XX_RTCCON_TICEN;
355 ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
356 ticnt &= S3C2410_TICNT_ENABLE;
359 seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no");
360 clk_disable(rtc_clk);
364 static const struct rtc_class_ops s3c_rtcops = {
365 .read_time = s3c_rtc_gettime,
366 .set_time = s3c_rtc_settime,
367 .read_alarm = s3c_rtc_getalarm,
368 .set_alarm = s3c_rtc_setalarm,
369 .proc = s3c_rtc_proc,
370 .alarm_irq_enable = s3c_rtc_setaie,
373 static void s3c_rtc_enable(struct platform_device *pdev, int en)
375 void __iomem *base = s3c_rtc_base;
378 if (s3c_rtc_base == NULL)
383 tmp = readw(base + S3C2410_RTCCON);
384 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
385 tmp &= ~S3C64XX_RTCCON_TICEN;
386 tmp &= ~S3C2410_RTCCON_RTCEN;
387 writew(tmp, base + S3C2410_RTCCON);
389 if (s3c_rtc_cpu_type != TYPE_S3C64XX) {
390 tmp = readb(base + S3C2410_TICNT);
391 tmp &= ~S3C2410_TICNT_ENABLE;
392 writeb(tmp, base + S3C2410_TICNT);
395 /* re-enable the device, and check it is ok */
397 if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) {
398 dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
400 tmp = readw(base + S3C2410_RTCCON);
401 writew(tmp | S3C2410_RTCCON_RTCEN,
402 base + S3C2410_RTCCON);
405 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) {
406 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
408 tmp = readw(base + S3C2410_RTCCON);
409 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
410 base + S3C2410_RTCCON);
413 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) {
414 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
416 tmp = readw(base + S3C2410_RTCCON);
417 writew(tmp & ~S3C2410_RTCCON_CLKRST,
418 base + S3C2410_RTCCON);
421 clk_disable(rtc_clk);
424 static int __devexit s3c_rtc_remove(struct platform_device *dev)
426 struct rtc_device *rtc = platform_get_drvdata(dev);
428 platform_set_drvdata(dev, NULL);
429 rtc_device_unregister(rtc);
431 s3c_rtc_setaie(&dev->dev, 0);
438 static const struct of_device_id s3c_rtc_dt_match[];
440 static inline int s3c_rtc_get_driver_data(struct platform_device *pdev)
443 struct s3c_rtc_drv_data *data;
444 if (pdev->dev.of_node) {
445 const struct of_device_id *match;
446 match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
447 data = (struct s3c_rtc_drv_data *) match->data;
448 return data->cpu_type;
451 return platform_get_device_id(pdev)->driver_data;
454 static int __devinit s3c_rtc_probe(struct platform_device *pdev)
456 struct rtc_device *rtc;
457 struct rtc_time rtc_tm;
458 struct resource *res;
462 pr_debug("%s: probe=%p\n", __func__, pdev);
466 s3c_rtc_tickno = platform_get_irq(pdev, 1);
467 if (s3c_rtc_tickno < 0) {
468 dev_err(&pdev->dev, "no irq for rtc tick\n");
469 return s3c_rtc_tickno;
472 s3c_rtc_alarmno = platform_get_irq(pdev, 0);
473 if (s3c_rtc_alarmno < 0) {
474 dev_err(&pdev->dev, "no irq for alarm\n");
475 return s3c_rtc_alarmno;
478 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
479 s3c_rtc_tickno, s3c_rtc_alarmno);
481 /* get the memory region */
483 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
485 dev_err(&pdev->dev, "failed to get memory region resource\n");
489 s3c_rtc_base = devm_request_and_ioremap(&pdev->dev, res);
490 if (s3c_rtc_base == NULL) {
491 dev_err(&pdev->dev, "failed to ioremap memory region\n");
495 rtc_clk = devm_clk_get(&pdev->dev, "rtc");
496 if (IS_ERR(rtc_clk)) {
497 dev_err(&pdev->dev, "failed to find rtc clock source\n");
498 ret = PTR_ERR(rtc_clk);
505 /* check to see if everything is setup correctly */
507 s3c_rtc_enable(pdev, 1);
509 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
510 readw(s3c_rtc_base + S3C2410_RTCCON));
512 device_init_wakeup(&pdev->dev, 1);
514 /* register RTC and exit */
516 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
520 dev_err(&pdev->dev, "cannot attach rtc\n");
525 s3c_rtc_cpu_type = s3c_rtc_get_driver_data(pdev);
529 s3c_rtc_gettime(NULL, &rtc_tm);
531 if (rtc_valid_tm(&rtc_tm)) {
532 rtc_tm.tm_year = 100;
539 s3c_rtc_settime(NULL, &rtc_tm);
541 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
544 if (s3c_rtc_cpu_type != TYPE_S3C2410)
545 rtc->max_user_freq = 32768;
547 rtc->max_user_freq = 128;
549 if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) {
550 tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
551 tmp |= S3C2443_RTCCON_TICSEL;
552 writew(tmp, s3c_rtc_base + S3C2410_RTCCON);
555 platform_set_drvdata(pdev, rtc);
557 s3c_rtc_setfreq(&pdev->dev, 1);
559 ret = devm_request_irq(&pdev->dev, s3c_rtc_alarmno, s3c_rtc_alarmirq,
560 0, "s3c2410-rtc alarm", rtc);
562 dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
566 ret = devm_request_irq(&pdev->dev, s3c_rtc_tickno, s3c_rtc_tickirq,
567 0, "s3c2410-rtc tick", rtc);
569 dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
573 clk_disable(rtc_clk);
578 platform_set_drvdata(pdev, NULL);
579 rtc_device_unregister(rtc);
582 s3c_rtc_enable(pdev, 0);
583 clk_disable(rtc_clk);
590 /* RTC Power management control */
592 static int ticnt_save, ticnt_en_save;
594 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
597 /* save TICNT for anyone using periodic interrupts */
598 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
599 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
600 ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
601 ticnt_en_save &= S3C64XX_RTCCON_TICEN;
603 s3c_rtc_enable(pdev, 0);
605 if (device_may_wakeup(&pdev->dev) && !wake_en) {
606 if (enable_irq_wake(s3c_rtc_alarmno) == 0)
609 dev_err(&pdev->dev, "enable_irq_wake failed\n");
611 clk_disable(rtc_clk);
616 static int s3c_rtc_resume(struct platform_device *pdev)
621 s3c_rtc_enable(pdev, 1);
622 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
623 if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
624 tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
625 writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
628 if (device_may_wakeup(&pdev->dev) && wake_en) {
629 disable_irq_wake(s3c_rtc_alarmno);
632 clk_disable(rtc_clk);
637 #define s3c_rtc_suspend NULL
638 #define s3c_rtc_resume NULL
642 static struct s3c_rtc_drv_data s3c_rtc_drv_data_array[] = {
643 [TYPE_S3C2410] = { TYPE_S3C2410 },
644 [TYPE_S3C2416] = { TYPE_S3C2416 },
645 [TYPE_S3C2443] = { TYPE_S3C2443 },
646 [TYPE_S3C64XX] = { TYPE_S3C64XX },
649 static const struct of_device_id s3c_rtc_dt_match[] = {
651 .compatible = "samsung,s3c2410-rtc",
652 .data = &s3c_rtc_drv_data_array[TYPE_S3C2410],
654 .compatible = "samsung,s3c2416-rtc",
655 .data = &s3c_rtc_drv_data_array[TYPE_S3C2416],
657 .compatible = "samsung,s3c2443-rtc",
658 .data = &s3c_rtc_drv_data_array[TYPE_S3C2443],
660 .compatible = "samsung,s3c6410-rtc",
661 .data = &s3c_rtc_drv_data_array[TYPE_S3C64XX],
665 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
668 static struct platform_device_id s3c_rtc_driver_ids[] = {
670 .name = "s3c2410-rtc",
671 .driver_data = TYPE_S3C2410,
673 .name = "s3c2416-rtc",
674 .driver_data = TYPE_S3C2416,
676 .name = "s3c2443-rtc",
677 .driver_data = TYPE_S3C2443,
679 .name = "s3c64xx-rtc",
680 .driver_data = TYPE_S3C64XX,
685 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
687 static struct platform_driver s3c_rtc_driver = {
688 .probe = s3c_rtc_probe,
689 .remove = __devexit_p(s3c_rtc_remove),
690 .suspend = s3c_rtc_suspend,
691 .resume = s3c_rtc_resume,
692 .id_table = s3c_rtc_driver_ids,
695 .owner = THIS_MODULE,
696 .of_match_table = of_match_ptr(s3c_rtc_dt_match),
700 module_platform_driver(s3c_rtc_driver);
702 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
703 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
704 MODULE_LICENSE("GPL");
705 MODULE_ALIAS("platform:s3c2410-rtc");