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 <mach/hardware.h>
30 #include <asm/uaccess.h>
33 #include <plat/regs-rtc.h>
40 /* I have yet to find an S3C implementation with more than one
41 * of these rtc blocks in */
43 static struct resource *s3c_rtc_mem;
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;
51 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
55 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
57 struct rtc_device *rdev = id;
59 rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
61 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
62 writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
67 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
69 struct rtc_device *rdev = id;
71 rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
73 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
74 writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
79 /* Update control registers */
80 static void s3c_rtc_setaie(int to)
84 pr_debug("%s: aie=%d\n", __func__, to);
86 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
89 tmp |= S3C2410_RTCALM_ALMEN;
91 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
94 static int s3c_rtc_setpie(struct device *dev, int enabled)
98 pr_debug("%s: pie=%d\n", __func__, enabled);
100 spin_lock_irq(&s3c_rtc_pie_lock);
102 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
103 tmp = readb(s3c_rtc_base + S3C2410_RTCCON);
104 tmp &= ~S3C64XX_RTCCON_TICEN;
107 tmp |= S3C64XX_RTCCON_TICEN;
109 writew(tmp, s3c_rtc_base + S3C2410_RTCCON);
111 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
112 tmp &= ~S3C2410_TICNT_ENABLE;
115 tmp |= S3C2410_TICNT_ENABLE;
117 writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
120 spin_unlock_irq(&s3c_rtc_pie_lock);
125 static int s3c_rtc_setfreq(struct device *dev, int freq)
127 struct platform_device *pdev = to_platform_device(dev);
128 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
129 unsigned int tmp = 0;
131 if (!is_power_of_2(freq))
134 spin_lock_irq(&s3c_rtc_pie_lock);
136 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
137 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
138 tmp &= S3C2410_TICNT_ENABLE;
141 tmp |= (rtc_dev->max_user_freq / freq)-1;
143 writel(tmp, s3c_rtc_base + S3C2410_TICNT);
144 spin_unlock_irq(&s3c_rtc_pie_lock);
149 /* Time read/write */
151 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
153 unsigned int have_retried = 0;
154 void __iomem *base = s3c_rtc_base;
157 rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
158 rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
159 rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
160 rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
161 rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
162 rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
164 /* the only way to work out wether the system was mid-update
165 * when we read it is to check the second counter, and if it
166 * is zero, then we re-try the entire read
169 if (rtc_tm->tm_sec == 0 && !have_retried) {
174 pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
175 rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
176 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
178 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
179 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
180 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
181 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
182 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
183 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
185 rtc_tm->tm_year += 100;
191 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
193 void __iomem *base = s3c_rtc_base;
194 int year = tm->tm_year - 100;
196 pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
197 tm->tm_year, tm->tm_mon, tm->tm_mday,
198 tm->tm_hour, tm->tm_min, tm->tm_sec);
200 /* we get around y2k by simply not supporting it */
202 if (year < 0 || year >= 100) {
203 dev_err(dev, "rtc only supports 100 years\n");
207 writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC);
208 writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN);
209 writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR);
210 writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
211 writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
212 writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
217 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
219 struct rtc_time *alm_tm = &alrm->time;
220 void __iomem *base = s3c_rtc_base;
223 alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
224 alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
225 alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
226 alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
227 alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
228 alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
230 alm_en = readb(base + S3C2410_RTCALM);
232 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
234 pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
236 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
237 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
240 /* decode the alarm enable field */
242 if (alm_en & S3C2410_RTCALM_SECEN)
243 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
245 alm_tm->tm_sec = 0xff;
247 if (alm_en & S3C2410_RTCALM_MINEN)
248 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
250 alm_tm->tm_min = 0xff;
252 if (alm_en & S3C2410_RTCALM_HOUREN)
253 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
255 alm_tm->tm_hour = 0xff;
257 if (alm_en & S3C2410_RTCALM_DAYEN)
258 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
260 alm_tm->tm_mday = 0xff;
262 if (alm_en & S3C2410_RTCALM_MONEN) {
263 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
266 alm_tm->tm_mon = 0xff;
269 if (alm_en & S3C2410_RTCALM_YEAREN)
270 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
272 alm_tm->tm_year = 0xffff;
277 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
279 struct rtc_time *tm = &alrm->time;
280 void __iomem *base = s3c_rtc_base;
281 unsigned int alrm_en;
283 pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
285 tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
286 tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
289 alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
290 writeb(0x00, base + S3C2410_RTCALM);
292 if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
293 alrm_en |= S3C2410_RTCALM_SECEN;
294 writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
297 if (tm->tm_min < 60 && tm->tm_min >= 0) {
298 alrm_en |= S3C2410_RTCALM_MINEN;
299 writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
302 if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
303 alrm_en |= S3C2410_RTCALM_HOUREN;
304 writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
307 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
309 writeb(alrm_en, base + S3C2410_RTCALM);
311 s3c_rtc_setaie(alrm->enabled);
316 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
320 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
321 ticnt = readb(s3c_rtc_base + S3C2410_RTCCON);
322 ticnt &= S3C64XX_RTCCON_TICEN;
324 ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
325 ticnt &= S3C2410_TICNT_ENABLE;
328 seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no");
332 static int s3c_rtc_open(struct device *dev)
334 struct platform_device *pdev = to_platform_device(dev);
335 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
338 ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
339 IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
342 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
346 ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
347 IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
350 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
357 free_irq(s3c_rtc_alarmno, rtc_dev);
361 static void s3c_rtc_release(struct device *dev)
363 struct platform_device *pdev = to_platform_device(dev);
364 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
366 /* do not clear AIE here, it may be needed for wake */
368 s3c_rtc_setpie(dev, 0);
369 free_irq(s3c_rtc_alarmno, rtc_dev);
370 free_irq(s3c_rtc_tickno, rtc_dev);
373 static const struct rtc_class_ops s3c_rtcops = {
374 .open = s3c_rtc_open,
375 .release = s3c_rtc_release,
376 .read_time = s3c_rtc_gettime,
377 .set_time = s3c_rtc_settime,
378 .read_alarm = s3c_rtc_getalarm,
379 .set_alarm = s3c_rtc_setalarm,
380 .irq_set_freq = s3c_rtc_setfreq,
381 .irq_set_state = s3c_rtc_setpie,
382 .proc = s3c_rtc_proc,
385 static void s3c_rtc_enable(struct platform_device *pdev, int en)
387 void __iomem *base = s3c_rtc_base;
390 if (s3c_rtc_base == NULL)
394 tmp = readb(base + S3C2410_RTCCON);
395 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
396 tmp &= ~S3C64XX_RTCCON_TICEN;
397 tmp &= ~S3C2410_RTCCON_RTCEN;
398 writeb(tmp, base + S3C2410_RTCCON);
400 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
401 tmp = readb(base + S3C2410_TICNT);
402 tmp &= ~S3C2410_TICNT_ENABLE;
403 writeb(tmp, base + S3C2410_TICNT);
406 /* re-enable the device, and check it is ok */
408 if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
409 dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
411 tmp = readb(base + S3C2410_RTCCON);
412 writeb(tmp|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
415 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
416 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
418 tmp = readb(base + S3C2410_RTCCON);
419 writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
422 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
423 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
425 tmp = readb(base + S3C2410_RTCCON);
426 writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
431 static int __devexit s3c_rtc_remove(struct platform_device *dev)
433 struct rtc_device *rtc = platform_get_drvdata(dev);
435 platform_set_drvdata(dev, NULL);
436 rtc_device_unregister(rtc);
438 s3c_rtc_setpie(&dev->dev, 0);
441 clk_disable(rtc_clk);
445 iounmap(s3c_rtc_base);
446 release_resource(s3c_rtc_mem);
452 static int __devinit s3c_rtc_probe(struct platform_device *pdev)
454 struct rtc_device *rtc;
455 struct resource *res;
459 pr_debug("%s: probe=%p\n", __func__, pdev);
463 s3c_rtc_tickno = platform_get_irq(pdev, 1);
464 if (s3c_rtc_tickno < 0) {
465 dev_err(&pdev->dev, "no irq for rtc tick\n");
469 s3c_rtc_alarmno = platform_get_irq(pdev, 0);
470 if (s3c_rtc_alarmno < 0) {
471 dev_err(&pdev->dev, "no irq for alarm\n");
475 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
476 s3c_rtc_tickno, s3c_rtc_alarmno);
478 /* get the memory region */
480 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
482 dev_err(&pdev->dev, "failed to get memory region resource\n");
486 s3c_rtc_mem = request_mem_region(res->start,
487 res->end-res->start+1,
490 if (s3c_rtc_mem == NULL) {
491 dev_err(&pdev->dev, "failed to reserve memory region\n");
496 s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
497 if (s3c_rtc_base == NULL) {
498 dev_err(&pdev->dev, "failed ioremap()\n");
503 rtc_clk = clk_get(&pdev->dev, "rtc");
504 if (IS_ERR(rtc_clk)) {
505 dev_err(&pdev->dev, "failed to find rtc clock source\n");
506 ret = PTR_ERR(rtc_clk);
513 /* check to see if everything is setup correctly */
515 s3c_rtc_enable(pdev, 1);
517 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
518 readb(s3c_rtc_base + S3C2410_RTCCON));
520 device_init_wakeup(&pdev->dev, 1);
522 /* register RTC and exit */
524 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
528 dev_err(&pdev->dev, "cannot attach rtc\n");
533 s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;
537 for (i = S3C2410_RTCSEC; i <= S3C2410_RTCYEAR; i += 0x4) {
538 tmp = readb(s3c_rtc_base + i);
540 if ((tmp & 0xf) > 0x9 || ((tmp >> 4) & 0xf) > 0x9)
541 writeb(0, s3c_rtc_base + i);
544 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
545 rtc->max_user_freq = 32768;
547 rtc->max_user_freq = 128;
549 platform_set_drvdata(pdev, rtc);
551 s3c_rtc_setfreq(&pdev->dev, 1);
556 s3c_rtc_enable(pdev, 0);
557 clk_disable(rtc_clk);
561 iounmap(s3c_rtc_base);
564 release_resource(s3c_rtc_mem);
572 /* RTC Power management control */
574 static int ticnt_save, ticnt_en_save;
576 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
578 /* save TICNT for anyone using periodic interrupts */
579 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
580 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
581 ticnt_en_save = readb(s3c_rtc_base + S3C2410_RTCCON);
582 ticnt_en_save &= S3C64XX_RTCCON_TICEN;
584 s3c_rtc_enable(pdev, 0);
586 if (device_may_wakeup(&pdev->dev))
587 enable_irq_wake(s3c_rtc_alarmno);
592 static int s3c_rtc_resume(struct platform_device *pdev)
596 s3c_rtc_enable(pdev, 1);
597 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
598 if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
599 tmp = readb(s3c_rtc_base + S3C2410_RTCCON);
600 writeb(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
603 if (device_may_wakeup(&pdev->dev))
604 disable_irq_wake(s3c_rtc_alarmno);
609 #define s3c_rtc_suspend NULL
610 #define s3c_rtc_resume NULL
613 static struct platform_device_id s3c_rtc_driver_ids[] = {
615 .name = "s3c2410-rtc",
616 .driver_data = TYPE_S3C2410,
618 .name = "s3c64xx-rtc",
619 .driver_data = TYPE_S3C64XX,
624 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
626 static struct platform_driver s3c_rtc_driver = {
627 .probe = s3c_rtc_probe,
628 .remove = __devexit_p(s3c_rtc_remove),
629 .suspend = s3c_rtc_suspend,
630 .resume = s3c_rtc_resume,
631 .id_table = s3c_rtc_driver_ids,
634 .owner = THIS_MODULE,
638 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
640 static int __init s3c_rtc_init(void)
643 return platform_driver_register(&s3c_rtc_driver);
646 static void __exit s3c_rtc_exit(void)
648 platform_driver_unregister(&s3c_rtc_driver);
651 module_init(s3c_rtc_init);
652 module_exit(s3c_rtc_exit);
654 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
655 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
656 MODULE_LICENSE("GPL");
657 MODULE_ALIAS("platform:s3c2410-rtc");