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>
23 #include <linux/log2.h>
24 #include <linux/slab.h>
26 #include <mach/hardware.h>
27 #include <asm/uaccess.h>
30 #include <plat/regs-rtc.h>
32 /* I have yet to find an S3C implementation with more than one
33 * of these rtc blocks in */
35 static struct resource
*s3c_rtc_mem
;
37 static void __iomem
*s3c_rtc_base
;
38 static int s3c_rtc_alarmno
= NO_IRQ
;
39 static int s3c_rtc_tickno
= NO_IRQ
;
41 static DEFINE_SPINLOCK(s3c_rtc_pie_lock
);
45 static irqreturn_t
s3c_rtc_alarmirq(int irq
, void *id
)
47 struct rtc_device
*rdev
= id
;
49 rtc_update_irq(rdev
, 1, RTC_AF
| RTC_IRQF
);
53 static irqreturn_t
s3c_rtc_tickirq(int irq
, void *id
)
55 struct rtc_device
*rdev
= id
;
57 rtc_update_irq(rdev
, 1, RTC_PF
| RTC_IRQF
);
61 /* Update control registers */
62 static void s3c_rtc_setaie(int to
)
66 pr_debug("%s: aie=%d\n", __func__
, to
);
68 tmp
= readb(s3c_rtc_base
+ S3C2410_RTCALM
) & ~S3C2410_RTCALM_ALMEN
;
71 tmp
|= S3C2410_RTCALM_ALMEN
;
73 writeb(tmp
, s3c_rtc_base
+ S3C2410_RTCALM
);
76 static int s3c_rtc_setpie(struct device
*dev
, int enabled
)
80 pr_debug("%s: pie=%d\n", __func__
, enabled
);
82 spin_lock_irq(&s3c_rtc_pie_lock
);
83 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & ~S3C2410_TICNT_ENABLE
;
86 tmp
|= S3C2410_TICNT_ENABLE
;
88 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
89 spin_unlock_irq(&s3c_rtc_pie_lock
);
94 static int s3c_rtc_setfreq(struct device
*dev
, int freq
)
98 if (!is_power_of_2(freq
))
101 spin_lock_irq(&s3c_rtc_pie_lock
);
103 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & S3C2410_TICNT_ENABLE
;
104 tmp
|= (128 / freq
)-1;
106 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
107 spin_unlock_irq(&s3c_rtc_pie_lock
);
112 /* Time read/write */
114 static int s3c_rtc_gettime(struct device
*dev
, struct rtc_time
*rtc_tm
)
116 unsigned int have_retried
= 0;
117 void __iomem
*base
= s3c_rtc_base
;
120 rtc_tm
->tm_min
= readb(base
+ S3C2410_RTCMIN
);
121 rtc_tm
->tm_hour
= readb(base
+ S3C2410_RTCHOUR
);
122 rtc_tm
->tm_mday
= readb(base
+ S3C2410_RTCDATE
);
123 rtc_tm
->tm_mon
= readb(base
+ S3C2410_RTCMON
);
124 rtc_tm
->tm_year
= readb(base
+ S3C2410_RTCYEAR
);
125 rtc_tm
->tm_sec
= readb(base
+ S3C2410_RTCSEC
);
127 /* the only way to work out wether the system was mid-update
128 * when we read it is to check the second counter, and if it
129 * is zero, then we re-try the entire read
132 if (rtc_tm
->tm_sec
== 0 && !have_retried
) {
137 pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
138 rtc_tm
->tm_year
, rtc_tm
->tm_mon
, rtc_tm
->tm_mday
,
139 rtc_tm
->tm_hour
, rtc_tm
->tm_min
, rtc_tm
->tm_sec
);
141 rtc_tm
->tm_sec
= bcd2bin(rtc_tm
->tm_sec
);
142 rtc_tm
->tm_min
= bcd2bin(rtc_tm
->tm_min
);
143 rtc_tm
->tm_hour
= bcd2bin(rtc_tm
->tm_hour
);
144 rtc_tm
->tm_mday
= bcd2bin(rtc_tm
->tm_mday
);
145 rtc_tm
->tm_mon
= bcd2bin(rtc_tm
->tm_mon
);
146 rtc_tm
->tm_year
= bcd2bin(rtc_tm
->tm_year
);
148 rtc_tm
->tm_year
+= 100;
154 static int s3c_rtc_settime(struct device
*dev
, struct rtc_time
*tm
)
156 void __iomem
*base
= s3c_rtc_base
;
157 int year
= tm
->tm_year
- 100;
159 pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
160 tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
161 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
163 /* we get around y2k by simply not supporting it */
165 if (year
< 0 || year
>= 100) {
166 dev_err(dev
, "rtc only supports 100 years\n");
170 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_RTCSEC
);
171 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_RTCMIN
);
172 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_RTCHOUR
);
173 writeb(bin2bcd(tm
->tm_mday
), base
+ S3C2410_RTCDATE
);
174 writeb(bin2bcd(tm
->tm_mon
+ 1), base
+ S3C2410_RTCMON
);
175 writeb(bin2bcd(year
), base
+ S3C2410_RTCYEAR
);
180 static int s3c_rtc_getalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
182 struct rtc_time
*alm_tm
= &alrm
->time
;
183 void __iomem
*base
= s3c_rtc_base
;
186 alm_tm
->tm_sec
= readb(base
+ S3C2410_ALMSEC
);
187 alm_tm
->tm_min
= readb(base
+ S3C2410_ALMMIN
);
188 alm_tm
->tm_hour
= readb(base
+ S3C2410_ALMHOUR
);
189 alm_tm
->tm_mon
= readb(base
+ S3C2410_ALMMON
);
190 alm_tm
->tm_mday
= readb(base
+ S3C2410_ALMDATE
);
191 alm_tm
->tm_year
= readb(base
+ S3C2410_ALMYEAR
);
193 alm_en
= readb(base
+ S3C2410_RTCALM
);
195 alrm
->enabled
= (alm_en
& S3C2410_RTCALM_ALMEN
) ? 1 : 0;
197 pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
199 alm_tm
->tm_year
, alm_tm
->tm_mon
, alm_tm
->tm_mday
,
200 alm_tm
->tm_hour
, alm_tm
->tm_min
, alm_tm
->tm_sec
);
203 /* decode the alarm enable field */
205 if (alm_en
& S3C2410_RTCALM_SECEN
)
206 alm_tm
->tm_sec
= bcd2bin(alm_tm
->tm_sec
);
208 alm_tm
->tm_sec
= 0xff;
210 if (alm_en
& S3C2410_RTCALM_MINEN
)
211 alm_tm
->tm_min
= bcd2bin(alm_tm
->tm_min
);
213 alm_tm
->tm_min
= 0xff;
215 if (alm_en
& S3C2410_RTCALM_HOUREN
)
216 alm_tm
->tm_hour
= bcd2bin(alm_tm
->tm_hour
);
218 alm_tm
->tm_hour
= 0xff;
220 if (alm_en
& S3C2410_RTCALM_DAYEN
)
221 alm_tm
->tm_mday
= bcd2bin(alm_tm
->tm_mday
);
223 alm_tm
->tm_mday
= 0xff;
225 if (alm_en
& S3C2410_RTCALM_MONEN
) {
226 alm_tm
->tm_mon
= bcd2bin(alm_tm
->tm_mon
);
229 alm_tm
->tm_mon
= 0xff;
232 if (alm_en
& S3C2410_RTCALM_YEAREN
)
233 alm_tm
->tm_year
= bcd2bin(alm_tm
->tm_year
);
235 alm_tm
->tm_year
= 0xffff;
240 static int s3c_rtc_setalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
242 struct rtc_time
*tm
= &alrm
->time
;
243 void __iomem
*base
= s3c_rtc_base
;
244 unsigned int alrm_en
;
246 pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
248 tm
->tm_mday
& 0xff, tm
->tm_mon
& 0xff, tm
->tm_year
& 0xff,
249 tm
->tm_hour
& 0xff, tm
->tm_min
& 0xff, tm
->tm_sec
);
252 alrm_en
= readb(base
+ S3C2410_RTCALM
) & S3C2410_RTCALM_ALMEN
;
253 writeb(0x00, base
+ S3C2410_RTCALM
);
255 if (tm
->tm_sec
< 60 && tm
->tm_sec
>= 0) {
256 alrm_en
|= S3C2410_RTCALM_SECEN
;
257 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_ALMSEC
);
260 if (tm
->tm_min
< 60 && tm
->tm_min
>= 0) {
261 alrm_en
|= S3C2410_RTCALM_MINEN
;
262 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_ALMMIN
);
265 if (tm
->tm_hour
< 24 && tm
->tm_hour
>= 0) {
266 alrm_en
|= S3C2410_RTCALM_HOUREN
;
267 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_ALMHOUR
);
270 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en
);
272 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
274 s3c_rtc_setaie(alrm
->enabled
);
277 enable_irq_wake(s3c_rtc_alarmno
);
279 disable_irq_wake(s3c_rtc_alarmno
);
284 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
286 unsigned int ticnt
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
288 seq_printf(seq
, "periodic_IRQ\t: %s\n",
289 (ticnt
& S3C2410_TICNT_ENABLE
) ? "yes" : "no" );
293 static int s3c_rtc_open(struct device
*dev
)
295 struct platform_device
*pdev
= to_platform_device(dev
);
296 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
299 ret
= request_irq(s3c_rtc_alarmno
, s3c_rtc_alarmirq
,
300 IRQF_DISABLED
, "s3c2410-rtc alarm", rtc_dev
);
303 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_alarmno
, ret
);
307 ret
= request_irq(s3c_rtc_tickno
, s3c_rtc_tickirq
,
308 IRQF_DISABLED
, "s3c2410-rtc tick", rtc_dev
);
311 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_tickno
, ret
);
318 free_irq(s3c_rtc_alarmno
, rtc_dev
);
322 static void s3c_rtc_release(struct device
*dev
)
324 struct platform_device
*pdev
= to_platform_device(dev
);
325 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
327 /* do not clear AIE here, it may be needed for wake */
329 s3c_rtc_setpie(dev
, 0);
330 free_irq(s3c_rtc_alarmno
, rtc_dev
);
331 free_irq(s3c_rtc_tickno
, rtc_dev
);
334 static const struct rtc_class_ops s3c_rtcops
= {
335 .open
= s3c_rtc_open
,
336 .release
= s3c_rtc_release
,
337 .read_time
= s3c_rtc_gettime
,
338 .set_time
= s3c_rtc_settime
,
339 .read_alarm
= s3c_rtc_getalarm
,
340 .set_alarm
= s3c_rtc_setalarm
,
341 .irq_set_freq
= s3c_rtc_setfreq
,
342 .irq_set_state
= s3c_rtc_setpie
,
343 .proc
= s3c_rtc_proc
,
346 static void s3c_rtc_enable(struct platform_device
*pdev
, int en
)
348 void __iomem
*base
= s3c_rtc_base
;
351 if (s3c_rtc_base
== NULL
)
355 tmp
= readb(base
+ S3C2410_RTCCON
);
356 writeb(tmp
& ~S3C2410_RTCCON_RTCEN
, base
+ S3C2410_RTCCON
);
358 tmp
= readb(base
+ S3C2410_TICNT
);
359 writeb(tmp
& ~S3C2410_TICNT_ENABLE
, base
+ S3C2410_TICNT
);
361 /* re-enable the device, and check it is ok */
363 if ((readb(base
+S3C2410_RTCCON
) & S3C2410_RTCCON_RTCEN
) == 0){
364 dev_info(&pdev
->dev
, "rtc disabled, re-enabling\n");
366 tmp
= readb(base
+ S3C2410_RTCCON
);
367 writeb(tmp
|S3C2410_RTCCON_RTCEN
, base
+S3C2410_RTCCON
);
370 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CNTSEL
)){
371 dev_info(&pdev
->dev
, "removing RTCCON_CNTSEL\n");
373 tmp
= readb(base
+ S3C2410_RTCCON
);
374 writeb(tmp
& ~S3C2410_RTCCON_CNTSEL
, base
+S3C2410_RTCCON
);
377 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CLKRST
)){
378 dev_info(&pdev
->dev
, "removing RTCCON_CLKRST\n");
380 tmp
= readb(base
+ S3C2410_RTCCON
);
381 writeb(tmp
& ~S3C2410_RTCCON_CLKRST
, base
+S3C2410_RTCCON
);
386 static int __devexit
s3c_rtc_remove(struct platform_device
*dev
)
388 struct rtc_device
*rtc
= platform_get_drvdata(dev
);
390 platform_set_drvdata(dev
, NULL
);
391 rtc_device_unregister(rtc
);
393 s3c_rtc_setpie(&dev
->dev
, 0);
396 iounmap(s3c_rtc_base
);
397 release_resource(s3c_rtc_mem
);
403 static int __devinit
s3c_rtc_probe(struct platform_device
*pdev
)
405 struct rtc_device
*rtc
;
406 struct resource
*res
;
409 pr_debug("%s: probe=%p\n", __func__
, pdev
);
413 s3c_rtc_tickno
= platform_get_irq(pdev
, 1);
414 if (s3c_rtc_tickno
< 0) {
415 dev_err(&pdev
->dev
, "no irq for rtc tick\n");
419 s3c_rtc_alarmno
= platform_get_irq(pdev
, 0);
420 if (s3c_rtc_alarmno
< 0) {
421 dev_err(&pdev
->dev
, "no irq for alarm\n");
425 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
426 s3c_rtc_tickno
, s3c_rtc_alarmno
);
428 /* get the memory region */
430 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
432 dev_err(&pdev
->dev
, "failed to get memory region resource\n");
436 s3c_rtc_mem
= request_mem_region(res
->start
,
437 res
->end
-res
->start
+1,
440 if (s3c_rtc_mem
== NULL
) {
441 dev_err(&pdev
->dev
, "failed to reserve memory region\n");
446 s3c_rtc_base
= ioremap(res
->start
, res
->end
- res
->start
+ 1);
447 if (s3c_rtc_base
== NULL
) {
448 dev_err(&pdev
->dev
, "failed ioremap()\n");
453 /* check to see if everything is setup correctly */
455 s3c_rtc_enable(pdev
, 1);
457 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
458 readb(s3c_rtc_base
+ S3C2410_RTCCON
));
460 s3c_rtc_setfreq(&pdev
->dev
, 1);
462 device_init_wakeup(&pdev
->dev
, 1);
464 /* register RTC and exit */
466 rtc
= rtc_device_register("s3c", &pdev
->dev
, &s3c_rtcops
,
470 dev_err(&pdev
->dev
, "cannot attach rtc\n");
475 rtc
->max_user_freq
= 128;
477 platform_set_drvdata(pdev
, rtc
);
481 s3c_rtc_enable(pdev
, 0);
482 iounmap(s3c_rtc_base
);
485 release_resource(s3c_rtc_mem
);
493 /* RTC Power management control */
495 static int ticnt_save
;
497 static int s3c_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
499 /* save TICNT for anyone using periodic interrupts */
500 ticnt_save
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
501 s3c_rtc_enable(pdev
, 0);
505 static int s3c_rtc_resume(struct platform_device
*pdev
)
507 s3c_rtc_enable(pdev
, 1);
508 writeb(ticnt_save
, s3c_rtc_base
+ S3C2410_TICNT
);
512 #define s3c_rtc_suspend NULL
513 #define s3c_rtc_resume NULL
516 static struct platform_driver s3c2410_rtc_driver
= {
517 .probe
= s3c_rtc_probe
,
518 .remove
= __devexit_p(s3c_rtc_remove
),
519 .suspend
= s3c_rtc_suspend
,
520 .resume
= s3c_rtc_resume
,
522 .name
= "s3c2410-rtc",
523 .owner
= THIS_MODULE
,
527 static char __initdata banner
[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
529 static int __init
s3c_rtc_init(void)
532 return platform_driver_register(&s3c2410_rtc_driver
);
535 static void __exit
s3c_rtc_exit(void)
537 platform_driver_unregister(&s3c2410_rtc_driver
);
540 module_init(s3c_rtc_init
);
541 module_exit(s3c_rtc_exit
);
543 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
544 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
545 MODULE_LICENSE("GPL");
546 MODULE_ALIAS("platform:s3c2410-rtc");