Merge branches 'sh-fixes-for-linus' and 'rmobile-fixes-for-linus' of git://git.kernel...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / rtc / rtc-s3c.c
blobcf953ecbfca934e8b9c7058f976610ff092016ae
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>
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>
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>
35 enum s3c_cpu_type {
36 TYPE_S3C2410,
37 TYPE_S3C64XX,
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);
53 /* IRQ Handlers */
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);
64 return IRQ_HANDLED;
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);
76 return IRQ_HANDLED;
79 /* Update control registers */
80 static void s3c_rtc_setaie(int to)
82 unsigned int tmp;
84 pr_debug("%s: aie=%d\n", __func__, to);
86 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
88 if (to)
89 tmp |= S3C2410_RTCALM_ALMEN;
91 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
94 static int s3c_rtc_setpie(struct device *dev, int enabled)
96 unsigned int tmp;
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 = readw(s3c_rtc_base + S3C2410_RTCCON);
104 tmp &= ~S3C64XX_RTCCON_TICEN;
106 if (enabled)
107 tmp |= S3C64XX_RTCCON_TICEN;
109 writew(tmp, s3c_rtc_base + S3C2410_RTCCON);
110 } else {
111 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
112 tmp &= ~S3C2410_TICNT_ENABLE;
114 if (enabled)
115 tmp |= S3C2410_TICNT_ENABLE;
117 writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
120 spin_unlock_irq(&s3c_rtc_pie_lock);
122 return 0;
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))
132 return -EINVAL;
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);
146 return 0;
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;
156 retry_get_time:
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) {
170 have_retried = 1;
171 goto retry_get_time;
174 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
175 1900 + 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;
186 rtc_tm->tm_mon -= 1;
188 return rtc_valid_tm(rtc_tm);
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 %04d.%02d.%02d %02d:%02d:%02d\n",
197 1900 + 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");
204 return -EINVAL;
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);
214 return 0;
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;
221 unsigned int alm_en;
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 %d, %04d.%02d.%02d %02d:%02d:%02d\n",
235 alm_en,
236 1900 + 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);
244 else
245 alm_tm->tm_sec = -1;
247 if (alm_en & S3C2410_RTCALM_MINEN)
248 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
249 else
250 alm_tm->tm_min = -1;
252 if (alm_en & S3C2410_RTCALM_HOUREN)
253 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
254 else
255 alm_tm->tm_hour = -1;
257 if (alm_en & S3C2410_RTCALM_DAYEN)
258 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
259 else
260 alm_tm->tm_mday = -1;
262 if (alm_en & S3C2410_RTCALM_MONEN) {
263 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
264 alm_tm->tm_mon -= 1;
265 } else {
266 alm_tm->tm_mon = -1;
269 if (alm_en & S3C2410_RTCALM_YEAREN)
270 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
271 else
272 alm_tm->tm_year = -1;
274 return 0;
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, %04d.%02d.%02d %02d:%02d:%02d\n",
284 alrm->enabled,
285 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
286 tm->tm_hour, tm->tm_min, 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);
313 return 0;
316 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
318 unsigned int ticnt;
320 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
321 ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
322 ticnt &= S3C64XX_RTCCON_TICEN;
323 } else {
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");
329 return 0;
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);
336 int ret;
338 ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
339 IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
341 if (ret) {
342 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
343 return ret;
346 ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
347 IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
349 if (ret) {
350 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
351 goto tick_err;
354 return ret;
356 tick_err:
357 free_irq(s3c_rtc_alarmno, rtc_dev);
358 return ret;
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,
383 .alarm_irq_enable = s3c_rtc_setaie,
386 static void s3c_rtc_enable(struct platform_device *pdev, int en)
388 void __iomem *base = s3c_rtc_base;
389 unsigned int tmp;
391 if (s3c_rtc_base == NULL)
392 return;
394 if (!en) {
395 tmp = readw(base + S3C2410_RTCCON);
396 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
397 tmp &= ~S3C64XX_RTCCON_TICEN;
398 tmp &= ~S3C2410_RTCCON_RTCEN;
399 writew(tmp, base + S3C2410_RTCCON);
401 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
402 tmp = readb(base + S3C2410_TICNT);
403 tmp &= ~S3C2410_TICNT_ENABLE;
404 writeb(tmp, base + S3C2410_TICNT);
406 } else {
407 /* re-enable the device, and check it is ok */
409 if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) {
410 dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
412 tmp = readw(base + S3C2410_RTCCON);
413 writew(tmp | S3C2410_RTCCON_RTCEN,
414 base + S3C2410_RTCCON);
417 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) {
418 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
420 tmp = readw(base + S3C2410_RTCCON);
421 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
422 base + S3C2410_RTCCON);
425 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) {
426 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
428 tmp = readw(base + S3C2410_RTCCON);
429 writew(tmp & ~S3C2410_RTCCON_CLKRST,
430 base + S3C2410_RTCCON);
435 static int __devexit s3c_rtc_remove(struct platform_device *dev)
437 struct rtc_device *rtc = platform_get_drvdata(dev);
439 platform_set_drvdata(dev, NULL);
440 rtc_device_unregister(rtc);
442 s3c_rtc_setpie(&dev->dev, 0);
443 s3c_rtc_setaie(0);
445 clk_disable(rtc_clk);
446 clk_put(rtc_clk);
447 rtc_clk = NULL;
449 iounmap(s3c_rtc_base);
450 release_resource(s3c_rtc_mem);
451 kfree(s3c_rtc_mem);
453 return 0;
456 static int __devinit s3c_rtc_probe(struct platform_device *pdev)
458 struct rtc_device *rtc;
459 struct rtc_time rtc_tm;
460 struct resource *res;
461 int ret;
463 pr_debug("%s: probe=%p\n", __func__, pdev);
465 /* find the IRQs */
467 s3c_rtc_tickno = platform_get_irq(pdev, 1);
468 if (s3c_rtc_tickno < 0) {
469 dev_err(&pdev->dev, "no irq for rtc tick\n");
470 return -ENOENT;
473 s3c_rtc_alarmno = platform_get_irq(pdev, 0);
474 if (s3c_rtc_alarmno < 0) {
475 dev_err(&pdev->dev, "no irq for alarm\n");
476 return -ENOENT;
479 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
480 s3c_rtc_tickno, s3c_rtc_alarmno);
482 /* get the memory region */
484 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
485 if (res == NULL) {
486 dev_err(&pdev->dev, "failed to get memory region resource\n");
487 return -ENOENT;
490 s3c_rtc_mem = request_mem_region(res->start,
491 res->end-res->start+1,
492 pdev->name);
494 if (s3c_rtc_mem == NULL) {
495 dev_err(&pdev->dev, "failed to reserve memory region\n");
496 ret = -ENOENT;
497 goto err_nores;
500 s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
501 if (s3c_rtc_base == NULL) {
502 dev_err(&pdev->dev, "failed ioremap()\n");
503 ret = -EINVAL;
504 goto err_nomap;
507 rtc_clk = clk_get(&pdev->dev, "rtc");
508 if (IS_ERR(rtc_clk)) {
509 dev_err(&pdev->dev, "failed to find rtc clock source\n");
510 ret = PTR_ERR(rtc_clk);
511 rtc_clk = NULL;
512 goto err_clk;
515 clk_enable(rtc_clk);
517 /* check to see if everything is setup correctly */
519 s3c_rtc_enable(pdev, 1);
521 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
522 readw(s3c_rtc_base + S3C2410_RTCCON));
524 device_init_wakeup(&pdev->dev, 1);
526 /* register RTC and exit */
528 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
529 THIS_MODULE);
531 if (IS_ERR(rtc)) {
532 dev_err(&pdev->dev, "cannot attach rtc\n");
533 ret = PTR_ERR(rtc);
534 goto err_nortc;
537 s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;
539 /* Check RTC Time */
541 s3c_rtc_gettime(NULL, &rtc_tm);
543 if (rtc_valid_tm(&rtc_tm)) {
544 rtc_tm.tm_year = 100;
545 rtc_tm.tm_mon = 0;
546 rtc_tm.tm_mday = 1;
547 rtc_tm.tm_hour = 0;
548 rtc_tm.tm_min = 0;
549 rtc_tm.tm_sec = 0;
551 s3c_rtc_settime(NULL, &rtc_tm);
553 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
556 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
557 rtc->max_user_freq = 32768;
558 else
559 rtc->max_user_freq = 128;
561 platform_set_drvdata(pdev, rtc);
563 s3c_rtc_setfreq(&pdev->dev, 1);
565 return 0;
567 err_nortc:
568 s3c_rtc_enable(pdev, 0);
569 clk_disable(rtc_clk);
570 clk_put(rtc_clk);
572 err_clk:
573 iounmap(s3c_rtc_base);
575 err_nomap:
576 release_resource(s3c_rtc_mem);
578 err_nores:
579 return ret;
582 #ifdef CONFIG_PM
584 /* RTC Power management control */
586 static int ticnt_save, ticnt_en_save;
588 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
590 /* save TICNT for anyone using periodic interrupts */
591 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
592 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
593 ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
594 ticnt_en_save &= S3C64XX_RTCCON_TICEN;
596 s3c_rtc_enable(pdev, 0);
598 if (device_may_wakeup(&pdev->dev))
599 enable_irq_wake(s3c_rtc_alarmno);
601 return 0;
604 static int s3c_rtc_resume(struct platform_device *pdev)
606 unsigned int tmp;
608 s3c_rtc_enable(pdev, 1);
609 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
610 if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
611 tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
612 writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
615 if (device_may_wakeup(&pdev->dev))
616 disable_irq_wake(s3c_rtc_alarmno);
618 return 0;
620 #else
621 #define s3c_rtc_suspend NULL
622 #define s3c_rtc_resume NULL
623 #endif
625 static struct platform_device_id s3c_rtc_driver_ids[] = {
627 .name = "s3c2410-rtc",
628 .driver_data = TYPE_S3C2410,
629 }, {
630 .name = "s3c64xx-rtc",
631 .driver_data = TYPE_S3C64XX,
636 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
638 static struct platform_driver s3c_rtc_driver = {
639 .probe = s3c_rtc_probe,
640 .remove = __devexit_p(s3c_rtc_remove),
641 .suspend = s3c_rtc_suspend,
642 .resume = s3c_rtc_resume,
643 .id_table = s3c_rtc_driver_ids,
644 .driver = {
645 .name = "s3c-rtc",
646 .owner = THIS_MODULE,
650 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
652 static int __init s3c_rtc_init(void)
654 printk(banner);
655 return platform_driver_register(&s3c_rtc_driver);
658 static void __exit s3c_rtc_exit(void)
660 platform_driver_unregister(&s3c_rtc_driver);
663 module_init(s3c_rtc_init);
664 module_exit(s3c_rtc_exit);
666 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
667 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
668 MODULE_LICENSE("GPL");
669 MODULE_ALIAS("platform:s3c2410-rtc");