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
);
54 static void s3c_rtc_alarm_clk_enable(bool enable
)
56 static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock
);
57 static bool alarm_clk_enabled
;
58 unsigned long irq_flags
;
60 spin_lock_irqsave(&s3c_rtc_alarm_clk_lock
, irq_flags
);
62 if (!alarm_clk_enabled
) {
64 alarm_clk_enabled
= true;
67 if (alarm_clk_enabled
) {
69 alarm_clk_enabled
= false;
72 spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock
, irq_flags
);
77 static irqreturn_t
s3c_rtc_alarmirq(int irq
, void *id
)
79 struct rtc_device
*rdev
= id
;
82 rtc_update_irq(rdev
, 1, RTC_AF
| RTC_IRQF
);
84 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
85 writeb(S3C2410_INTP_ALM
, s3c_rtc_base
+ S3C2410_INTP
);
89 s3c_rtc_alarm_clk_enable(false);
94 static irqreturn_t
s3c_rtc_tickirq(int irq
, void *id
)
96 struct rtc_device
*rdev
= id
;
99 rtc_update_irq(rdev
, 1, RTC_PF
| RTC_IRQF
);
101 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
102 writeb(S3C2410_INTP_TIC
, s3c_rtc_base
+ S3C2410_INTP
);
104 clk_disable(rtc_clk
);
108 /* Update control registers */
109 static int s3c_rtc_setaie(struct device
*dev
, unsigned int enabled
)
113 pr_debug("%s: aie=%d\n", __func__
, enabled
);
116 tmp
= readb(s3c_rtc_base
+ S3C2410_RTCALM
) & ~S3C2410_RTCALM_ALMEN
;
119 tmp
|= S3C2410_RTCALM_ALMEN
;
121 writeb(tmp
, s3c_rtc_base
+ S3C2410_RTCALM
);
122 clk_disable(rtc_clk
);
124 s3c_rtc_alarm_clk_enable(enabled
);
129 static int s3c_rtc_setfreq(struct device
*dev
, int freq
)
131 struct platform_device
*pdev
= to_platform_device(dev
);
132 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
133 unsigned int tmp
= 0;
135 if (!is_power_of_2(freq
))
139 spin_lock_irq(&s3c_rtc_pie_lock
);
141 if (s3c_rtc_cpu_type
== TYPE_S3C2410
) {
142 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
143 tmp
&= S3C2410_TICNT_ENABLE
;
146 tmp
|= (rtc_dev
->max_user_freq
/ freq
)-1;
148 writel(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
149 spin_unlock_irq(&s3c_rtc_pie_lock
);
150 clk_disable(rtc_clk
);
155 /* Time read/write */
157 static int s3c_rtc_gettime(struct device
*dev
, struct rtc_time
*rtc_tm
)
159 unsigned int have_retried
= 0;
160 void __iomem
*base
= s3c_rtc_base
;
164 rtc_tm
->tm_min
= readb(base
+ S3C2410_RTCMIN
);
165 rtc_tm
->tm_hour
= readb(base
+ S3C2410_RTCHOUR
);
166 rtc_tm
->tm_mday
= readb(base
+ S3C2410_RTCDATE
);
167 rtc_tm
->tm_mon
= readb(base
+ S3C2410_RTCMON
);
168 rtc_tm
->tm_year
= readb(base
+ S3C2410_RTCYEAR
);
169 rtc_tm
->tm_sec
= readb(base
+ S3C2410_RTCSEC
);
171 /* the only way to work out wether the system was mid-update
172 * when we read it is to check the second counter, and if it
173 * is zero, then we re-try the entire read
176 if (rtc_tm
->tm_sec
== 0 && !have_retried
) {
181 rtc_tm
->tm_sec
= bcd2bin(rtc_tm
->tm_sec
);
182 rtc_tm
->tm_min
= bcd2bin(rtc_tm
->tm_min
);
183 rtc_tm
->tm_hour
= bcd2bin(rtc_tm
->tm_hour
);
184 rtc_tm
->tm_mday
= bcd2bin(rtc_tm
->tm_mday
);
185 rtc_tm
->tm_mon
= bcd2bin(rtc_tm
->tm_mon
);
186 rtc_tm
->tm_year
= bcd2bin(rtc_tm
->tm_year
);
188 rtc_tm
->tm_year
+= 100;
190 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
191 1900 + rtc_tm
->tm_year
, rtc_tm
->tm_mon
, rtc_tm
->tm_mday
,
192 rtc_tm
->tm_hour
, rtc_tm
->tm_min
, rtc_tm
->tm_sec
);
196 clk_disable(rtc_clk
);
197 return rtc_valid_tm(rtc_tm
);
200 static int s3c_rtc_settime(struct device
*dev
, struct rtc_time
*tm
)
202 void __iomem
*base
= s3c_rtc_base
;
203 int year
= tm
->tm_year
- 100;
205 pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
206 1900 + tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
207 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
209 /* we get around y2k by simply not supporting it */
211 if (year
< 0 || year
>= 100) {
212 dev_err(dev
, "rtc only supports 100 years\n");
217 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_RTCSEC
);
218 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_RTCMIN
);
219 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_RTCHOUR
);
220 writeb(bin2bcd(tm
->tm_mday
), base
+ S3C2410_RTCDATE
);
221 writeb(bin2bcd(tm
->tm_mon
+ 1), base
+ S3C2410_RTCMON
);
222 writeb(bin2bcd(year
), base
+ S3C2410_RTCYEAR
);
223 clk_disable(rtc_clk
);
228 static int s3c_rtc_getalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
230 struct rtc_time
*alm_tm
= &alrm
->time
;
231 void __iomem
*base
= s3c_rtc_base
;
235 alm_tm
->tm_sec
= readb(base
+ S3C2410_ALMSEC
);
236 alm_tm
->tm_min
= readb(base
+ S3C2410_ALMMIN
);
237 alm_tm
->tm_hour
= readb(base
+ S3C2410_ALMHOUR
);
238 alm_tm
->tm_mon
= readb(base
+ S3C2410_ALMMON
);
239 alm_tm
->tm_mday
= readb(base
+ S3C2410_ALMDATE
);
240 alm_tm
->tm_year
= readb(base
+ S3C2410_ALMYEAR
);
242 alm_en
= readb(base
+ S3C2410_RTCALM
);
244 alrm
->enabled
= (alm_en
& S3C2410_RTCALM_ALMEN
) ? 1 : 0;
246 pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
248 1900 + alm_tm
->tm_year
, alm_tm
->tm_mon
, alm_tm
->tm_mday
,
249 alm_tm
->tm_hour
, alm_tm
->tm_min
, alm_tm
->tm_sec
);
252 /* decode the alarm enable field */
254 if (alm_en
& S3C2410_RTCALM_SECEN
)
255 alm_tm
->tm_sec
= bcd2bin(alm_tm
->tm_sec
);
259 if (alm_en
& S3C2410_RTCALM_MINEN
)
260 alm_tm
->tm_min
= bcd2bin(alm_tm
->tm_min
);
264 if (alm_en
& S3C2410_RTCALM_HOUREN
)
265 alm_tm
->tm_hour
= bcd2bin(alm_tm
->tm_hour
);
267 alm_tm
->tm_hour
= -1;
269 if (alm_en
& S3C2410_RTCALM_DAYEN
)
270 alm_tm
->tm_mday
= bcd2bin(alm_tm
->tm_mday
);
272 alm_tm
->tm_mday
= -1;
274 if (alm_en
& S3C2410_RTCALM_MONEN
) {
275 alm_tm
->tm_mon
= bcd2bin(alm_tm
->tm_mon
);
281 if (alm_en
& S3C2410_RTCALM_YEAREN
)
282 alm_tm
->tm_year
= bcd2bin(alm_tm
->tm_year
);
284 alm_tm
->tm_year
= -1;
286 clk_disable(rtc_clk
);
290 static int s3c_rtc_setalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
292 struct rtc_time
*tm
= &alrm
->time
;
293 void __iomem
*base
= s3c_rtc_base
;
294 unsigned int alrm_en
;
297 pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
299 1900 + tm
->tm_year
, tm
->tm_mon
+ 1, tm
->tm_mday
,
300 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
302 alrm_en
= readb(base
+ S3C2410_RTCALM
) & S3C2410_RTCALM_ALMEN
;
303 writeb(0x00, base
+ S3C2410_RTCALM
);
305 if (tm
->tm_sec
< 60 && tm
->tm_sec
>= 0) {
306 alrm_en
|= S3C2410_RTCALM_SECEN
;
307 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_ALMSEC
);
310 if (tm
->tm_min
< 60 && tm
->tm_min
>= 0) {
311 alrm_en
|= S3C2410_RTCALM_MINEN
;
312 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_ALMMIN
);
315 if (tm
->tm_hour
< 24 && tm
->tm_hour
>= 0) {
316 alrm_en
|= S3C2410_RTCALM_HOUREN
;
317 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_ALMHOUR
);
320 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en
);
322 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
324 s3c_rtc_setaie(dev
, alrm
->enabled
);
326 clk_disable(rtc_clk
);
330 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
335 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
) {
336 ticnt
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
337 ticnt
&= S3C64XX_RTCCON_TICEN
;
339 ticnt
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
340 ticnt
&= S3C2410_TICNT_ENABLE
;
343 seq_printf(seq
, "periodic_IRQ\t: %s\n", ticnt
? "yes" : "no");
344 clk_disable(rtc_clk
);
348 static const struct rtc_class_ops s3c_rtcops
= {
349 .read_time
= s3c_rtc_gettime
,
350 .set_time
= s3c_rtc_settime
,
351 .read_alarm
= s3c_rtc_getalarm
,
352 .set_alarm
= s3c_rtc_setalarm
,
353 .proc
= s3c_rtc_proc
,
354 .alarm_irq_enable
= s3c_rtc_setaie
,
357 static void s3c_rtc_enable(struct platform_device
*pdev
, int en
)
359 void __iomem
*base
= s3c_rtc_base
;
362 if (s3c_rtc_base
== NULL
)
367 tmp
= readw(base
+ S3C2410_RTCCON
);
368 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
369 tmp
&= ~S3C64XX_RTCCON_TICEN
;
370 tmp
&= ~S3C2410_RTCCON_RTCEN
;
371 writew(tmp
, base
+ S3C2410_RTCCON
);
373 if (s3c_rtc_cpu_type
== TYPE_S3C2410
) {
374 tmp
= readb(base
+ S3C2410_TICNT
);
375 tmp
&= ~S3C2410_TICNT_ENABLE
;
376 writeb(tmp
, base
+ S3C2410_TICNT
);
379 /* re-enable the device, and check it is ok */
381 if ((readw(base
+S3C2410_RTCCON
) & S3C2410_RTCCON_RTCEN
) == 0) {
382 dev_info(&pdev
->dev
, "rtc disabled, re-enabling\n");
384 tmp
= readw(base
+ S3C2410_RTCCON
);
385 writew(tmp
| S3C2410_RTCCON_RTCEN
,
386 base
+ S3C2410_RTCCON
);
389 if ((readw(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CNTSEL
)) {
390 dev_info(&pdev
->dev
, "removing RTCCON_CNTSEL\n");
392 tmp
= readw(base
+ S3C2410_RTCCON
);
393 writew(tmp
& ~S3C2410_RTCCON_CNTSEL
,
394 base
+ S3C2410_RTCCON
);
397 if ((readw(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CLKRST
)) {
398 dev_info(&pdev
->dev
, "removing RTCCON_CLKRST\n");
400 tmp
= readw(base
+ S3C2410_RTCCON
);
401 writew(tmp
& ~S3C2410_RTCCON_CLKRST
,
402 base
+ S3C2410_RTCCON
);
405 clk_disable(rtc_clk
);
408 static int __devexit
s3c_rtc_remove(struct platform_device
*dev
)
410 struct rtc_device
*rtc
= platform_get_drvdata(dev
);
412 free_irq(s3c_rtc_alarmno
, rtc
);
413 free_irq(s3c_rtc_tickno
, rtc
);
415 platform_set_drvdata(dev
, NULL
);
416 rtc_device_unregister(rtc
);
418 s3c_rtc_setaie(&dev
->dev
, 0);
423 iounmap(s3c_rtc_base
);
424 release_resource(s3c_rtc_mem
);
430 static int __devinit
s3c_rtc_probe(struct platform_device
*pdev
)
432 struct rtc_device
*rtc
;
433 struct rtc_time rtc_tm
;
434 struct resource
*res
;
437 pr_debug("%s: probe=%p\n", __func__
, pdev
);
441 s3c_rtc_tickno
= platform_get_irq(pdev
, 1);
442 if (s3c_rtc_tickno
< 0) {
443 dev_err(&pdev
->dev
, "no irq for rtc tick\n");
447 s3c_rtc_alarmno
= platform_get_irq(pdev
, 0);
448 if (s3c_rtc_alarmno
< 0) {
449 dev_err(&pdev
->dev
, "no irq for alarm\n");
453 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
454 s3c_rtc_tickno
, s3c_rtc_alarmno
);
456 /* get the memory region */
458 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
460 dev_err(&pdev
->dev
, "failed to get memory region resource\n");
464 s3c_rtc_mem
= request_mem_region(res
->start
, resource_size(res
),
467 if (s3c_rtc_mem
== NULL
) {
468 dev_err(&pdev
->dev
, "failed to reserve memory region\n");
473 s3c_rtc_base
= ioremap(res
->start
, resource_size(res
));
474 if (s3c_rtc_base
== NULL
) {
475 dev_err(&pdev
->dev
, "failed ioremap()\n");
480 rtc_clk
= clk_get(&pdev
->dev
, "rtc");
481 if (IS_ERR(rtc_clk
)) {
482 dev_err(&pdev
->dev
, "failed to find rtc clock source\n");
483 ret
= PTR_ERR(rtc_clk
);
490 /* check to see if everything is setup correctly */
492 s3c_rtc_enable(pdev
, 1);
494 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
495 readw(s3c_rtc_base
+ S3C2410_RTCCON
));
497 device_init_wakeup(&pdev
->dev
, 1);
499 /* register RTC and exit */
501 rtc
= rtc_device_register("s3c", &pdev
->dev
, &s3c_rtcops
,
505 dev_err(&pdev
->dev
, "cannot attach rtc\n");
510 s3c_rtc_cpu_type
= platform_get_device_id(pdev
)->driver_data
;
514 s3c_rtc_gettime(NULL
, &rtc_tm
);
516 if (rtc_valid_tm(&rtc_tm
)) {
517 rtc_tm
.tm_year
= 100;
524 s3c_rtc_settime(NULL
, &rtc_tm
);
526 dev_warn(&pdev
->dev
, "warning: invalid RTC value so initializing it\n");
529 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
)
530 rtc
->max_user_freq
= 32768;
532 rtc
->max_user_freq
= 128;
534 platform_set_drvdata(pdev
, rtc
);
536 s3c_rtc_setfreq(&pdev
->dev
, 1);
538 ret
= request_irq(s3c_rtc_alarmno
, s3c_rtc_alarmirq
,
539 IRQF_DISABLED
, "s3c2410-rtc alarm", rtc
);
541 dev_err(&pdev
->dev
, "IRQ%d error %d\n", s3c_rtc_alarmno
, ret
);
545 ret
= request_irq(s3c_rtc_tickno
, s3c_rtc_tickirq
,
546 IRQF_DISABLED
, "s3c2410-rtc tick", rtc
);
548 dev_err(&pdev
->dev
, "IRQ%d error %d\n", s3c_rtc_tickno
, ret
);
549 free_irq(s3c_rtc_alarmno
, rtc
);
553 clk_disable(rtc_clk
);
558 free_irq(s3c_rtc_alarmno
, rtc
);
561 platform_set_drvdata(pdev
, NULL
);
562 rtc_device_unregister(rtc
);
565 s3c_rtc_enable(pdev
, 0);
566 clk_disable(rtc_clk
);
570 iounmap(s3c_rtc_base
);
573 release_resource(s3c_rtc_mem
);
581 /* RTC Power management control */
583 static int ticnt_save
, ticnt_en_save
;
585 static int s3c_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
588 /* save TICNT for anyone using periodic interrupts */
589 ticnt_save
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
590 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
) {
591 ticnt_en_save
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
592 ticnt_en_save
&= S3C64XX_RTCCON_TICEN
;
594 s3c_rtc_enable(pdev
, 0);
596 if (device_may_wakeup(&pdev
->dev
) && !wake_en
) {
597 if (enable_irq_wake(s3c_rtc_alarmno
) == 0)
600 dev_err(&pdev
->dev
, "enable_irq_wake failed\n");
602 clk_disable(rtc_clk
);
607 static int s3c_rtc_resume(struct platform_device
*pdev
)
612 s3c_rtc_enable(pdev
, 1);
613 writeb(ticnt_save
, s3c_rtc_base
+ S3C2410_TICNT
);
614 if (s3c_rtc_cpu_type
== TYPE_S3C64XX
&& ticnt_en_save
) {
615 tmp
= readw(s3c_rtc_base
+ S3C2410_RTCCON
);
616 writew(tmp
| ticnt_en_save
, s3c_rtc_base
+ S3C2410_RTCCON
);
619 if (device_may_wakeup(&pdev
->dev
) && wake_en
) {
620 disable_irq_wake(s3c_rtc_alarmno
);
623 clk_disable(rtc_clk
);
628 #define s3c_rtc_suspend NULL
629 #define s3c_rtc_resume NULL
632 static struct platform_device_id s3c_rtc_driver_ids
[] = {
634 .name
= "s3c2410-rtc",
635 .driver_data
= TYPE_S3C2410
,
637 .name
= "s3c64xx-rtc",
638 .driver_data
= TYPE_S3C64XX
,
643 MODULE_DEVICE_TABLE(platform
, s3c_rtc_driver_ids
);
645 static struct platform_driver s3c_rtc_driver
= {
646 .probe
= s3c_rtc_probe
,
647 .remove
= __devexit_p(s3c_rtc_remove
),
648 .suspend
= s3c_rtc_suspend
,
649 .resume
= s3c_rtc_resume
,
650 .id_table
= s3c_rtc_driver_ids
,
653 .owner
= THIS_MODULE
,
657 static char __initdata banner
[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
659 static int __init
s3c_rtc_init(void)
662 return platform_driver_register(&s3c_rtc_driver
);
665 static void __exit
s3c_rtc_exit(void)
667 platform_driver_unregister(&s3c_rtc_driver
);
670 module_init(s3c_rtc_init
);
671 module_exit(s3c_rtc_exit
);
673 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
674 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
675 MODULE_LICENSE("GPL");
676 MODULE_ALIAS("platform:s3c2410-rtc");