1 /* drivers/rtc/rtc-s3c.c
3 * Copyright (c) 2004,2006 Simtec Electronics
4 * Ben Dooks, <ben@simtec.co.uk>
5 * http://armlinux.simtec.co.uk/
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * S3C2410/S3C2440/S3C24XX Internal RTC Driver
14 #include <linux/module.h>
16 #include <linux/string.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/interrupt.h>
20 #include <linux/rtc.h>
21 #include <linux/bcd.h>
22 #include <linux/clk.h>
24 #include <asm/hardware.h>
25 #include <asm/uaccess.h>
30 #include <asm/mach/time.h>
32 #include <asm/arch/regs-rtc.h>
34 /* I have yet to find an S3C implementation with more than one
35 * of these rtc blocks in */
37 static struct resource
*s3c_rtc_mem
;
39 static void __iomem
*s3c_rtc_base
;
40 static int s3c_rtc_alarmno
= NO_IRQ
;
41 static int s3c_rtc_tickno
= NO_IRQ
;
42 static int s3c_rtc_freq
= 1;
44 static DEFINE_SPINLOCK(s3c_rtc_pie_lock
);
45 static unsigned int tick_count
;
49 static irqreturn_t
s3c_rtc_alarmirq(int irq
, void *id
)
51 struct rtc_device
*rdev
= id
;
53 rtc_update_irq(&rdev
->class_dev
, 1, RTC_AF
| RTC_IRQF
);
57 static irqreturn_t
s3c_rtc_tickirq(int irq
, void *id
)
59 struct rtc_device
*rdev
= id
;
61 rtc_update_irq(&rdev
->class_dev
, tick_count
++, RTC_PF
| RTC_IRQF
);
65 /* Update control registers */
66 static void s3c_rtc_setaie(int to
)
70 pr_debug("%s: aie=%d\n", __FUNCTION__
, to
);
72 tmp
= readb(s3c_rtc_base
+ S3C2410_RTCALM
) & ~S3C2410_RTCALM_ALMEN
;
75 tmp
|= S3C2410_RTCALM_ALMEN
;
77 writeb(tmp
, s3c_rtc_base
+ S3C2410_RTCALM
);
80 static void s3c_rtc_setpie(int to
)
84 pr_debug("%s: pie=%d\n", __FUNCTION__
, to
);
86 spin_lock_irq(&s3c_rtc_pie_lock
);
87 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & ~S3C2410_TICNT_ENABLE
;
90 tmp
|= S3C2410_TICNT_ENABLE
;
92 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
93 spin_unlock_irq(&s3c_rtc_pie_lock
);
96 static void s3c_rtc_setfreq(int freq
)
100 spin_lock_irq(&s3c_rtc_pie_lock
);
101 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & S3C2410_TICNT_ENABLE
;
105 tmp
|= (128 / freq
)-1;
107 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
108 spin_unlock_irq(&s3c_rtc_pie_lock
);
111 /* Time read/write */
113 static int s3c_rtc_gettime(struct device
*dev
, struct rtc_time
*rtc_tm
)
115 unsigned int have_retried
= 0;
116 void __iomem
*base
= s3c_rtc_base
;
119 rtc_tm
->tm_min
= readb(base
+ S3C2410_RTCMIN
);
120 rtc_tm
->tm_hour
= readb(base
+ S3C2410_RTCHOUR
);
121 rtc_tm
->tm_mday
= readb(base
+ S3C2410_RTCDATE
);
122 rtc_tm
->tm_mon
= readb(base
+ S3C2410_RTCMON
);
123 rtc_tm
->tm_year
= readb(base
+ S3C2410_RTCYEAR
);
124 rtc_tm
->tm_sec
= readb(base
+ S3C2410_RTCSEC
);
126 /* the only way to work out wether the system was mid-update
127 * when we read it is to check the second counter, and if it
128 * is zero, then we re-try the entire read
131 if (rtc_tm
->tm_sec
== 0 && !have_retried
) {
136 pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
137 rtc_tm
->tm_year
, rtc_tm
->tm_mon
, rtc_tm
->tm_mday
,
138 rtc_tm
->tm_hour
, rtc_tm
->tm_min
, rtc_tm
->tm_sec
);
140 BCD_TO_BIN(rtc_tm
->tm_sec
);
141 BCD_TO_BIN(rtc_tm
->tm_min
);
142 BCD_TO_BIN(rtc_tm
->tm_hour
);
143 BCD_TO_BIN(rtc_tm
->tm_mday
);
144 BCD_TO_BIN(rtc_tm
->tm_mon
);
145 BCD_TO_BIN(rtc_tm
->tm_year
);
147 rtc_tm
->tm_year
+= 100;
153 static int s3c_rtc_settime(struct device
*dev
, struct rtc_time
*tm
)
155 void __iomem
*base
= s3c_rtc_base
;
156 int year
= tm
->tm_year
- 100;
158 pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
159 tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
160 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
162 /* we get around y2k by simply not supporting it */
164 if (year
< 0 || year
>= 100) {
165 dev_err(dev
, "rtc only supports 100 years\n");
169 writeb(BIN2BCD(tm
->tm_sec
), base
+ S3C2410_RTCSEC
);
170 writeb(BIN2BCD(tm
->tm_min
), base
+ S3C2410_RTCMIN
);
171 writeb(BIN2BCD(tm
->tm_hour
), base
+ S3C2410_RTCHOUR
);
172 writeb(BIN2BCD(tm
->tm_mday
), base
+ S3C2410_RTCDATE
);
173 writeb(BIN2BCD(tm
->tm_mon
+ 1), base
+ S3C2410_RTCMON
);
174 writeb(BIN2BCD(year
), base
+ S3C2410_RTCYEAR
);
179 static int s3c_rtc_getalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
181 struct rtc_time
*alm_tm
= &alrm
->time
;
182 void __iomem
*base
= s3c_rtc_base
;
185 alm_tm
->tm_sec
= readb(base
+ S3C2410_ALMSEC
);
186 alm_tm
->tm_min
= readb(base
+ S3C2410_ALMMIN
);
187 alm_tm
->tm_hour
= readb(base
+ S3C2410_ALMHOUR
);
188 alm_tm
->tm_mon
= readb(base
+ S3C2410_ALMMON
);
189 alm_tm
->tm_mday
= readb(base
+ S3C2410_ALMDATE
);
190 alm_tm
->tm_year
= readb(base
+ S3C2410_ALMYEAR
);
192 alm_en
= readb(base
+ S3C2410_RTCALM
);
194 pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
196 alm_tm
->tm_year
, alm_tm
->tm_mon
, alm_tm
->tm_mday
,
197 alm_tm
->tm_hour
, alm_tm
->tm_min
, alm_tm
->tm_sec
);
200 /* decode the alarm enable field */
202 if (alm_en
& S3C2410_RTCALM_SECEN
)
203 BCD_TO_BIN(alm_tm
->tm_sec
);
205 alm_tm
->tm_sec
= 0xff;
207 if (alm_en
& S3C2410_RTCALM_MINEN
)
208 BCD_TO_BIN(alm_tm
->tm_min
);
210 alm_tm
->tm_min
= 0xff;
212 if (alm_en
& S3C2410_RTCALM_HOUREN
)
213 BCD_TO_BIN(alm_tm
->tm_hour
);
215 alm_tm
->tm_hour
= 0xff;
217 if (alm_en
& S3C2410_RTCALM_DAYEN
)
218 BCD_TO_BIN(alm_tm
->tm_mday
);
220 alm_tm
->tm_mday
= 0xff;
222 if (alm_en
& S3C2410_RTCALM_MONEN
) {
223 BCD_TO_BIN(alm_tm
->tm_mon
);
226 alm_tm
->tm_mon
= 0xff;
229 if (alm_en
& S3C2410_RTCALM_YEAREN
)
230 BCD_TO_BIN(alm_tm
->tm_year
);
232 alm_tm
->tm_year
= 0xffff;
237 static int s3c_rtc_setalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
239 struct rtc_time
*tm
= &alrm
->time
;
240 void __iomem
*base
= s3c_rtc_base
;
241 unsigned int alrm_en
;
243 pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
245 tm
->tm_mday
& 0xff, tm
->tm_mon
& 0xff, tm
->tm_year
& 0xff,
246 tm
->tm_hour
& 0xff, tm
->tm_min
& 0xff, tm
->tm_sec
);
249 alrm_en
= readb(base
+ S3C2410_RTCALM
) & S3C2410_RTCALM_ALMEN
;
250 writeb(0x00, base
+ S3C2410_RTCALM
);
252 if (tm
->tm_sec
< 60 && tm
->tm_sec
>= 0) {
253 alrm_en
|= S3C2410_RTCALM_SECEN
;
254 writeb(BIN2BCD(tm
->tm_sec
), base
+ S3C2410_ALMSEC
);
257 if (tm
->tm_min
< 60 && tm
->tm_min
>= 0) {
258 alrm_en
|= S3C2410_RTCALM_MINEN
;
259 writeb(BIN2BCD(tm
->tm_min
), base
+ S3C2410_ALMMIN
);
262 if (tm
->tm_hour
< 24 && tm
->tm_hour
>= 0) {
263 alrm_en
|= S3C2410_RTCALM_HOUREN
;
264 writeb(BIN2BCD(tm
->tm_hour
), base
+ S3C2410_ALMHOUR
);
267 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en
);
269 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
272 alrm_en
= readb(base
+ S3C2410_RTCALM
);
273 alrm_en
&= ~S3C2410_RTCALM_ALMEN
;
274 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
275 disable_irq_wake(s3c_rtc_alarmno
);
279 enable_irq_wake(s3c_rtc_alarmno
);
281 disable_irq_wake(s3c_rtc_alarmno
);
286 static int s3c_rtc_ioctl(struct device
*dev
,
287 unsigned int cmd
, unsigned long arg
)
289 unsigned int ret
= -ENOIOCTLCMD
;
294 s3c_rtc_setaie((cmd
== RTC_AIE_ON
) ? 1 : 0);
301 s3c_rtc_setpie((cmd
== RTC_PIE_ON
) ? 1 : 0);
306 ret
= put_user(s3c_rtc_freq
, (unsigned long __user
*)arg
);
310 /* check for power of 2 */
312 if ((arg
& (arg
-1)) != 0 || arg
< 1) {
317 pr_debug("s3c2410_rtc: setting frequency %ld\n", arg
);
319 s3c_rtc_setfreq(arg
);
332 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
334 unsigned int rtcalm
= readb(s3c_rtc_base
+ S3C2410_RTCALM
);
335 unsigned int ticnt
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
337 seq_printf(seq
, "alarm_IRQ\t: %s\n",
338 (rtcalm
& S3C2410_RTCALM_ALMEN
) ? "yes" : "no" );
340 seq_printf(seq
, "periodic_IRQ\t: %s\n",
341 (ticnt
& S3C2410_TICNT_ENABLE
) ? "yes" : "no" );
343 seq_printf(seq
, "periodic_freq\t: %d\n", s3c_rtc_freq
);
348 static int s3c_rtc_open(struct device
*dev
)
350 struct platform_device
*pdev
= to_platform_device(dev
);
351 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
354 ret
= request_irq(s3c_rtc_alarmno
, s3c_rtc_alarmirq
,
355 SA_INTERRUPT
, "s3c2410-rtc alarm", rtc_dev
);
358 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_alarmno
, ret
);
362 ret
= request_irq(s3c_rtc_tickno
, s3c_rtc_tickirq
,
363 SA_INTERRUPT
, "s3c2410-rtc tick", rtc_dev
);
366 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_tickno
, ret
);
373 free_irq(s3c_rtc_alarmno
, rtc_dev
);
377 static void s3c_rtc_release(struct device
*dev
)
379 struct platform_device
*pdev
= to_platform_device(dev
);
380 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
382 /* do not clear AIE here, it may be needed for wake */
385 free_irq(s3c_rtc_alarmno
, rtc_dev
);
386 free_irq(s3c_rtc_tickno
, rtc_dev
);
389 static const struct rtc_class_ops s3c_rtcops
= {
390 .open
= s3c_rtc_open
,
391 .release
= s3c_rtc_release
,
392 .ioctl
= s3c_rtc_ioctl
,
393 .read_time
= s3c_rtc_gettime
,
394 .set_time
= s3c_rtc_settime
,
395 .read_alarm
= s3c_rtc_getalarm
,
396 .set_alarm
= s3c_rtc_setalarm
,
397 .proc
= s3c_rtc_proc
,
400 static void s3c_rtc_enable(struct platform_device
*pdev
, int en
)
402 void __iomem
*base
= s3c_rtc_base
;
405 if (s3c_rtc_base
== NULL
)
409 tmp
= readb(base
+ S3C2410_RTCCON
);
410 writeb(tmp
& ~S3C2410_RTCCON_RTCEN
, base
+ S3C2410_RTCCON
);
412 tmp
= readb(base
+ S3C2410_TICNT
);
413 writeb(tmp
& ~S3C2410_TICNT_ENABLE
, base
+ S3C2410_TICNT
);
415 /* re-enable the device, and check it is ok */
417 if ((readb(base
+S3C2410_RTCCON
) & S3C2410_RTCCON_RTCEN
) == 0){
418 dev_info(&pdev
->dev
, "rtc disabled, re-enabling\n");
420 tmp
= readb(base
+ S3C2410_RTCCON
);
421 writeb(tmp
|S3C2410_RTCCON_RTCEN
, base
+S3C2410_RTCCON
);
424 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CNTSEL
)){
425 dev_info(&pdev
->dev
, "removing RTCCON_CNTSEL\n");
427 tmp
= readb(base
+ S3C2410_RTCCON
);
428 writeb(tmp
& ~S3C2410_RTCCON_CNTSEL
, base
+S3C2410_RTCCON
);
431 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CLKRST
)){
432 dev_info(&pdev
->dev
, "removing RTCCON_CLKRST\n");
434 tmp
= readb(base
+ S3C2410_RTCCON
);
435 writeb(tmp
& ~S3C2410_RTCCON_CLKRST
, base
+S3C2410_RTCCON
);
440 static int s3c_rtc_remove(struct platform_device
*dev
)
442 struct rtc_device
*rtc
= platform_get_drvdata(dev
);
444 platform_set_drvdata(dev
, NULL
);
445 rtc_device_unregister(rtc
);
450 iounmap(s3c_rtc_base
);
451 release_resource(s3c_rtc_mem
);
457 static int s3c_rtc_probe(struct platform_device
*pdev
)
459 struct rtc_device
*rtc
;
460 struct resource
*res
;
463 pr_debug("%s: probe=%p\n", __FUNCTION__
, 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 /* check to see if everything is setup correctly */
509 s3c_rtc_enable(pdev
, 1);
511 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
512 readb(s3c_rtc_base
+ S3C2410_RTCCON
));
514 s3c_rtc_setfreq(s3c_rtc_freq
);
516 /* register RTC and exit */
518 rtc
= rtc_device_register("s3c", &pdev
->dev
, &s3c_rtcops
,
522 dev_err(&pdev
->dev
, "cannot attach rtc\n");
527 rtc
->max_user_freq
= 128;
529 platform_set_drvdata(pdev
, rtc
);
533 s3c_rtc_enable(pdev
, 0);
534 iounmap(s3c_rtc_base
);
537 release_resource(s3c_rtc_mem
);
545 /* RTC Power management control */
547 static struct timespec s3c_rtc_delta
;
549 static int ticnt_save
;
551 static int s3c_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
554 struct timespec time
;
558 /* save TICNT for anyone using periodic interrupts */
560 ticnt_save
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
562 /* calculate time delta for suspend */
564 s3c_rtc_gettime(&pdev
->dev
, &tm
);
565 rtc_tm_to_time(&tm
, &time
.tv_sec
);
566 save_time_delta(&s3c_rtc_delta
, &time
);
567 s3c_rtc_enable(pdev
, 0);
572 static int s3c_rtc_resume(struct platform_device
*pdev
)
575 struct timespec time
;
579 s3c_rtc_enable(pdev
, 1);
580 s3c_rtc_gettime(&pdev
->dev
, &tm
);
581 rtc_tm_to_time(&tm
, &time
.tv_sec
);
582 restore_time_delta(&s3c_rtc_delta
, &time
);
584 writeb(ticnt_save
, s3c_rtc_base
+ S3C2410_TICNT
);
588 #define s3c_rtc_suspend NULL
589 #define s3c_rtc_resume NULL
592 static struct platform_driver s3c2410_rtcdrv
= {
593 .probe
= s3c_rtc_probe
,
594 .remove
= s3c_rtc_remove
,
595 .suspend
= s3c_rtc_suspend
,
596 .resume
= s3c_rtc_resume
,
598 .name
= "s3c2410-rtc",
599 .owner
= THIS_MODULE
,
603 static char __initdata banner
[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
605 static int __init
s3c_rtc_init(void)
608 return platform_driver_register(&s3c2410_rtcdrv
);
611 static void __exit
s3c_rtc_exit(void)
613 platform_driver_unregister(&s3c2410_rtcdrv
);
616 module_init(s3c_rtc_init
);
617 module_exit(s3c_rtc_exit
);
619 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
620 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
621 MODULE_LICENSE("GPL");