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
;
50 static enum s3c_cpu_type s3c_rtc_cpu_type
;
52 static DEFINE_SPINLOCK(s3c_rtc_pie_lock
);
56 static irqreturn_t
s3c_rtc_alarmirq(int irq
, void *id
)
58 struct rtc_device
*rdev
= id
;
60 rtc_update_irq(rdev
, 1, RTC_AF
| RTC_IRQF
);
62 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
63 writeb(S3C2410_INTP_ALM
, s3c_rtc_base
+ S3C2410_INTP
);
68 static irqreturn_t
s3c_rtc_tickirq(int irq
, void *id
)
70 struct rtc_device
*rdev
= id
;
72 rtc_update_irq(rdev
, 1, RTC_PF
| RTC_IRQF
);
74 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
75 writeb(S3C2410_INTP_TIC
, s3c_rtc_base
+ S3C2410_INTP
);
80 /* Update control registers */
81 static int s3c_rtc_setaie(struct device
*dev
, unsigned int enabled
)
85 pr_debug("%s: aie=%d\n", __func__
, enabled
);
87 tmp
= readb(s3c_rtc_base
+ S3C2410_RTCALM
) & ~S3C2410_RTCALM_ALMEN
;
90 tmp
|= S3C2410_RTCALM_ALMEN
;
92 writeb(tmp
, s3c_rtc_base
+ S3C2410_RTCALM
);
97 static int s3c_rtc_setfreq(struct device
*dev
, int freq
)
99 struct platform_device
*pdev
= to_platform_device(dev
);
100 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
101 unsigned int tmp
= 0;
103 if (!is_power_of_2(freq
))
106 spin_lock_irq(&s3c_rtc_pie_lock
);
108 if (s3c_rtc_cpu_type
== TYPE_S3C2410
) {
109 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
110 tmp
&= S3C2410_TICNT_ENABLE
;
113 tmp
|= (rtc_dev
->max_user_freq
/ freq
)-1;
115 writel(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
116 spin_unlock_irq(&s3c_rtc_pie_lock
);
121 /* Time read/write */
123 static int s3c_rtc_gettime(struct device
*dev
, struct rtc_time
*rtc_tm
)
125 unsigned int have_retried
= 0;
126 void __iomem
*base
= s3c_rtc_base
;
129 rtc_tm
->tm_min
= readb(base
+ S3C2410_RTCMIN
);
130 rtc_tm
->tm_hour
= readb(base
+ S3C2410_RTCHOUR
);
131 rtc_tm
->tm_mday
= readb(base
+ S3C2410_RTCDATE
);
132 rtc_tm
->tm_mon
= readb(base
+ S3C2410_RTCMON
);
133 rtc_tm
->tm_year
= readb(base
+ S3C2410_RTCYEAR
);
134 rtc_tm
->tm_sec
= readb(base
+ S3C2410_RTCSEC
);
136 /* the only way to work out wether the system was mid-update
137 * when we read it is to check the second counter, and if it
138 * is zero, then we re-try the entire read
141 if (rtc_tm
->tm_sec
== 0 && !have_retried
) {
146 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
147 1900 + rtc_tm
->tm_year
, rtc_tm
->tm_mon
, rtc_tm
->tm_mday
,
148 rtc_tm
->tm_hour
, rtc_tm
->tm_min
, rtc_tm
->tm_sec
);
150 rtc_tm
->tm_sec
= bcd2bin(rtc_tm
->tm_sec
);
151 rtc_tm
->tm_min
= bcd2bin(rtc_tm
->tm_min
);
152 rtc_tm
->tm_hour
= bcd2bin(rtc_tm
->tm_hour
);
153 rtc_tm
->tm_mday
= bcd2bin(rtc_tm
->tm_mday
);
154 rtc_tm
->tm_mon
= bcd2bin(rtc_tm
->tm_mon
);
155 rtc_tm
->tm_year
= bcd2bin(rtc_tm
->tm_year
);
157 rtc_tm
->tm_year
+= 100;
160 return rtc_valid_tm(rtc_tm
);
163 static int s3c_rtc_settime(struct device
*dev
, struct rtc_time
*tm
)
165 void __iomem
*base
= s3c_rtc_base
;
166 int year
= tm
->tm_year
- 100;
168 pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
169 1900 + tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
170 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
172 /* we get around y2k by simply not supporting it */
174 if (year
< 0 || year
>= 100) {
175 dev_err(dev
, "rtc only supports 100 years\n");
179 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_RTCSEC
);
180 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_RTCMIN
);
181 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_RTCHOUR
);
182 writeb(bin2bcd(tm
->tm_mday
), base
+ S3C2410_RTCDATE
);
183 writeb(bin2bcd(tm
->tm_mon
+ 1), base
+ S3C2410_RTCMON
);
184 writeb(bin2bcd(year
), base
+ S3C2410_RTCYEAR
);
189 static int s3c_rtc_getalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
191 struct rtc_time
*alm_tm
= &alrm
->time
;
192 void __iomem
*base
= s3c_rtc_base
;
195 alm_tm
->tm_sec
= readb(base
+ S3C2410_ALMSEC
);
196 alm_tm
->tm_min
= readb(base
+ S3C2410_ALMMIN
);
197 alm_tm
->tm_hour
= readb(base
+ S3C2410_ALMHOUR
);
198 alm_tm
->tm_mon
= readb(base
+ S3C2410_ALMMON
);
199 alm_tm
->tm_mday
= readb(base
+ S3C2410_ALMDATE
);
200 alm_tm
->tm_year
= readb(base
+ S3C2410_ALMYEAR
);
202 alm_en
= readb(base
+ S3C2410_RTCALM
);
204 alrm
->enabled
= (alm_en
& S3C2410_RTCALM_ALMEN
) ? 1 : 0;
206 pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
208 1900 + alm_tm
->tm_year
, alm_tm
->tm_mon
, alm_tm
->tm_mday
,
209 alm_tm
->tm_hour
, alm_tm
->tm_min
, alm_tm
->tm_sec
);
212 /* decode the alarm enable field */
214 if (alm_en
& S3C2410_RTCALM_SECEN
)
215 alm_tm
->tm_sec
= bcd2bin(alm_tm
->tm_sec
);
219 if (alm_en
& S3C2410_RTCALM_MINEN
)
220 alm_tm
->tm_min
= bcd2bin(alm_tm
->tm_min
);
224 if (alm_en
& S3C2410_RTCALM_HOUREN
)
225 alm_tm
->tm_hour
= bcd2bin(alm_tm
->tm_hour
);
227 alm_tm
->tm_hour
= -1;
229 if (alm_en
& S3C2410_RTCALM_DAYEN
)
230 alm_tm
->tm_mday
= bcd2bin(alm_tm
->tm_mday
);
232 alm_tm
->tm_mday
= -1;
234 if (alm_en
& S3C2410_RTCALM_MONEN
) {
235 alm_tm
->tm_mon
= bcd2bin(alm_tm
->tm_mon
);
241 if (alm_en
& S3C2410_RTCALM_YEAREN
)
242 alm_tm
->tm_year
= bcd2bin(alm_tm
->tm_year
);
244 alm_tm
->tm_year
= -1;
249 static int s3c_rtc_setalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
251 struct rtc_time
*tm
= &alrm
->time
;
252 void __iomem
*base
= s3c_rtc_base
;
253 unsigned int alrm_en
;
255 pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
257 1900 + tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
258 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
261 alrm_en
= readb(base
+ S3C2410_RTCALM
) & S3C2410_RTCALM_ALMEN
;
262 writeb(0x00, base
+ S3C2410_RTCALM
);
264 if (tm
->tm_sec
< 60 && tm
->tm_sec
>= 0) {
265 alrm_en
|= S3C2410_RTCALM_SECEN
;
266 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_ALMSEC
);
269 if (tm
->tm_min
< 60 && tm
->tm_min
>= 0) {
270 alrm_en
|= S3C2410_RTCALM_MINEN
;
271 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_ALMMIN
);
274 if (tm
->tm_hour
< 24 && tm
->tm_hour
>= 0) {
275 alrm_en
|= S3C2410_RTCALM_HOUREN
;
276 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_ALMHOUR
);
279 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en
);
281 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
283 s3c_rtc_setaie(dev
, alrm
->enabled
);
288 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
292 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
) {
293 ticnt
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
294 ticnt
&= S3C64XX_RTCCON_TICEN
;
296 ticnt
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
297 ticnt
&= S3C2410_TICNT_ENABLE
;
300 seq_printf(seq
, "periodic_IRQ\t: %s\n", ticnt
? "yes" : "no");
304 static int s3c_rtc_open(struct device
*dev
)
306 struct platform_device
*pdev
= to_platform_device(dev
);
307 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
310 ret
= request_irq(s3c_rtc_alarmno
, s3c_rtc_alarmirq
,
311 IRQF_DISABLED
, "s3c2410-rtc alarm", rtc_dev
);
314 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_alarmno
, ret
);
318 ret
= request_irq(s3c_rtc_tickno
, s3c_rtc_tickirq
,
319 IRQF_DISABLED
, "s3c2410-rtc tick", rtc_dev
);
322 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_tickno
, ret
);
329 free_irq(s3c_rtc_alarmno
, rtc_dev
);
333 static void s3c_rtc_release(struct device
*dev
)
335 struct platform_device
*pdev
= to_platform_device(dev
);
336 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
338 /* do not clear AIE here, it may be needed for wake */
340 free_irq(s3c_rtc_alarmno
, rtc_dev
);
341 free_irq(s3c_rtc_tickno
, rtc_dev
);
344 static const struct rtc_class_ops s3c_rtcops
= {
345 .open
= s3c_rtc_open
,
346 .release
= s3c_rtc_release
,
347 .read_time
= s3c_rtc_gettime
,
348 .set_time
= s3c_rtc_settime
,
349 .read_alarm
= s3c_rtc_getalarm
,
350 .set_alarm
= s3c_rtc_setalarm
,
351 .proc
= s3c_rtc_proc
,
352 .alarm_irq_enable
= s3c_rtc_setaie
,
355 static void s3c_rtc_enable(struct platform_device
*pdev
, int en
)
357 void __iomem
*base
= s3c_rtc_base
;
360 if (s3c_rtc_base
== NULL
)
364 tmp
= readw(base
+ S3C2410_RTCCON
);
365 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
366 tmp
&= ~S3C64XX_RTCCON_TICEN
;
367 tmp
&= ~S3C2410_RTCCON_RTCEN
;
368 writew(tmp
, base
+ S3C2410_RTCCON
);
370 if (s3c_rtc_cpu_type
== TYPE_S3C2410
) {
371 tmp
= readb(base
+ S3C2410_TICNT
);
372 tmp
&= ~S3C2410_TICNT_ENABLE
;
373 writeb(tmp
, base
+ S3C2410_TICNT
);
376 /* re-enable the device, and check it is ok */
378 if ((readw(base
+S3C2410_RTCCON
) & S3C2410_RTCCON_RTCEN
) == 0) {
379 dev_info(&pdev
->dev
, "rtc disabled, re-enabling\n");
381 tmp
= readw(base
+ S3C2410_RTCCON
);
382 writew(tmp
| S3C2410_RTCCON_RTCEN
,
383 base
+ S3C2410_RTCCON
);
386 if ((readw(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CNTSEL
)) {
387 dev_info(&pdev
->dev
, "removing RTCCON_CNTSEL\n");
389 tmp
= readw(base
+ S3C2410_RTCCON
);
390 writew(tmp
& ~S3C2410_RTCCON_CNTSEL
,
391 base
+ S3C2410_RTCCON
);
394 if ((readw(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CLKRST
)) {
395 dev_info(&pdev
->dev
, "removing RTCCON_CLKRST\n");
397 tmp
= readw(base
+ S3C2410_RTCCON
);
398 writew(tmp
& ~S3C2410_RTCCON_CLKRST
,
399 base
+ S3C2410_RTCCON
);
404 static int __devexit
s3c_rtc_remove(struct platform_device
*dev
)
406 struct rtc_device
*rtc
= platform_get_drvdata(dev
);
408 platform_set_drvdata(dev
, NULL
);
409 rtc_device_unregister(rtc
);
411 s3c_rtc_setaie(&dev
->dev
, 0);
413 clk_disable(rtc_clk
);
417 iounmap(s3c_rtc_base
);
418 release_resource(s3c_rtc_mem
);
424 static int __devinit
s3c_rtc_probe(struct platform_device
*pdev
)
426 struct rtc_device
*rtc
;
427 struct rtc_time rtc_tm
;
428 struct resource
*res
;
431 pr_debug("%s: probe=%p\n", __func__
, pdev
);
435 s3c_rtc_tickno
= platform_get_irq(pdev
, 1);
436 if (s3c_rtc_tickno
< 0) {
437 dev_err(&pdev
->dev
, "no irq for rtc tick\n");
441 s3c_rtc_alarmno
= platform_get_irq(pdev
, 0);
442 if (s3c_rtc_alarmno
< 0) {
443 dev_err(&pdev
->dev
, "no irq for alarm\n");
447 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
448 s3c_rtc_tickno
, s3c_rtc_alarmno
);
450 /* get the memory region */
452 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
454 dev_err(&pdev
->dev
, "failed to get memory region resource\n");
458 s3c_rtc_mem
= request_mem_region(res
->start
,
459 res
->end
-res
->start
+1,
462 if (s3c_rtc_mem
== NULL
) {
463 dev_err(&pdev
->dev
, "failed to reserve memory region\n");
468 s3c_rtc_base
= ioremap(res
->start
, res
->end
- res
->start
+ 1);
469 if (s3c_rtc_base
== NULL
) {
470 dev_err(&pdev
->dev
, "failed ioremap()\n");
475 rtc_clk
= clk_get(&pdev
->dev
, "rtc");
476 if (IS_ERR(rtc_clk
)) {
477 dev_err(&pdev
->dev
, "failed to find rtc clock source\n");
478 ret
= PTR_ERR(rtc_clk
);
485 /* check to see if everything is setup correctly */
487 s3c_rtc_enable(pdev
, 1);
489 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
490 readw(s3c_rtc_base
+ S3C2410_RTCCON
));
492 device_init_wakeup(&pdev
->dev
, 1);
494 /* register RTC and exit */
496 rtc
= rtc_device_register("s3c", &pdev
->dev
, &s3c_rtcops
,
500 dev_err(&pdev
->dev
, "cannot attach rtc\n");
505 s3c_rtc_cpu_type
= platform_get_device_id(pdev
)->driver_data
;
509 s3c_rtc_gettime(NULL
, &rtc_tm
);
511 if (rtc_valid_tm(&rtc_tm
)) {
512 rtc_tm
.tm_year
= 100;
519 s3c_rtc_settime(NULL
, &rtc_tm
);
521 dev_warn(&pdev
->dev
, "warning: invalid RTC value so initializing it\n");
524 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
525 rtc
->max_user_freq
= 32768;
527 rtc
->max_user_freq
= 128;
529 platform_set_drvdata(pdev
, rtc
);
531 s3c_rtc_setfreq(&pdev
->dev
, 1);
536 s3c_rtc_enable(pdev
, 0);
537 clk_disable(rtc_clk
);
541 iounmap(s3c_rtc_base
);
544 release_resource(s3c_rtc_mem
);
552 /* RTC Power management control */
554 static int ticnt_save
, ticnt_en_save
;
556 static int s3c_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
558 /* save TICNT for anyone using periodic interrupts */
559 ticnt_save
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
560 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
) {
561 ticnt_en_save
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
562 ticnt_en_save
&= S3C64XX_RTCCON_TICEN
;
564 s3c_rtc_enable(pdev
, 0);
566 if (device_may_wakeup(&pdev
->dev
) && !wake_en
) {
567 if (enable_irq_wake(s3c_rtc_alarmno
) == 0)
570 dev_err(&pdev
->dev
, "enable_irq_wake failed\n");
576 static int s3c_rtc_resume(struct platform_device
*pdev
)
580 s3c_rtc_enable(pdev
, 1);
581 writeb(ticnt_save
, s3c_rtc_base
+ S3C2410_TICNT
);
582 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
&& ticnt_en_save
) {
583 tmp
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
584 writew(tmp
| ticnt_en_save
, s3c_rtc_base
+ S3C2410_RTCCON
);
587 if (device_may_wakeup(&pdev
->dev
) && wake_en
) {
588 disable_irq_wake(s3c_rtc_alarmno
);
595 #define s3c_rtc_suspend NULL
596 #define s3c_rtc_resume NULL
599 static struct platform_device_id s3c_rtc_driver_ids
[] = {
601 .name
= "s3c2410-rtc",
602 .driver_data
= TYPE_S3C2410
,
604 .name
= "s3c64xx-rtc",
605 .driver_data
= TYPE_S3C64XX
,
610 MODULE_DEVICE_TABLE(platform
, s3c_rtc_driver_ids
);
612 static struct platform_driver s3c_rtc_driver
= {
613 .probe
= s3c_rtc_probe
,
614 .remove
= __devexit_p(s3c_rtc_remove
),
615 .suspend
= s3c_rtc_suspend
,
616 .resume
= s3c_rtc_resume
,
617 .id_table
= s3c_rtc_driver_ids
,
620 .owner
= THIS_MODULE
,
624 static char __initdata banner
[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
626 static int __init
s3c_rtc_init(void)
629 return platform_driver_register(&s3c_rtc_driver
);
632 static void __exit
s3c_rtc_exit(void)
634 platform_driver_unregister(&s3c_rtc_driver
);
637 module_init(s3c_rtc_init
);
638 module_exit(s3c_rtc_exit
);
640 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
641 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
642 MODULE_LICENSE("GPL");
643 MODULE_ALIAS("platform:s3c2410-rtc");