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
= readw(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 %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;
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");
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 %d, %04d.%02d.%02d %02d:%02d:%02d\n",
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
);
247 if (alm_en
& S3C2410_RTCALM_MINEN
)
248 alm_tm
->tm_min
= bcd2bin(alm_tm
->tm_min
);
252 if (alm_en
& S3C2410_RTCALM_HOUREN
)
253 alm_tm
->tm_hour
= bcd2bin(alm_tm
->tm_hour
);
255 alm_tm
->tm_hour
= -1;
257 if (alm_en
& S3C2410_RTCALM_DAYEN
)
258 alm_tm
->tm_mday
= bcd2bin(alm_tm
->tm_mday
);
260 alm_tm
->tm_mday
= -1;
262 if (alm_en
& S3C2410_RTCALM_MONEN
) {
263 alm_tm
->tm_mon
= bcd2bin(alm_tm
->tm_mon
);
269 if (alm_en
& S3C2410_RTCALM_YEAREN
)
270 alm_tm
->tm_year
= bcd2bin(alm_tm
->tm_year
);
272 alm_tm
->tm_year
= -1;
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",
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
);
316 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
320 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
) {
321 ticnt
= readw(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
,
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
;
391 if (s3c_rtc_base
== NULL
)
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
);
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);
445 clk_disable(rtc_clk
);
449 iounmap(s3c_rtc_base
);
450 release_resource(s3c_rtc_mem
);
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
;
463 pr_debug("%s: probe=%p\n", __func__
, pdev
);
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");
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");
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);
486 dev_err(&pdev
->dev
, "failed to get memory region resource\n");
490 s3c_rtc_mem
= request_mem_region(res
->start
,
491 res
->end
-res
->start
+1,
494 if (s3c_rtc_mem
== NULL
) {
495 dev_err(&pdev
->dev
, "failed to reserve memory region\n");
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");
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
);
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
,
532 dev_err(&pdev
->dev
, "cannot attach rtc\n");
537 s3c_rtc_cpu_type
= platform_get_device_id(pdev
)->driver_data
;
541 s3c_rtc_gettime(NULL
, &rtc_tm
);
543 if (rtc_valid_tm(&rtc_tm
)) {
544 rtc_tm
.tm_year
= 100;
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;
559 rtc
->max_user_freq
= 128;
561 platform_set_drvdata(pdev
, rtc
);
563 s3c_rtc_setfreq(&pdev
->dev
, 1);
568 s3c_rtc_enable(pdev
, 0);
569 clk_disable(rtc_clk
);
573 iounmap(s3c_rtc_base
);
576 release_resource(s3c_rtc_mem
);
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
);
604 static int s3c_rtc_resume(struct platform_device
*pdev
)
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
);
621 #define s3c_rtc_suspend NULL
622 #define s3c_rtc_resume NULL
625 static struct platform_device_id s3c_rtc_driver_ids
[] = {
627 .name
= "s3c2410-rtc",
628 .driver_data
= TYPE_S3C2410
,
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
,
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)
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");