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>
25 #include <mach/hardware.h>
26 #include <asm/uaccess.h>
29 #include <asm/plat-s3c/regs-rtc.h>
31 /* I have yet to find an S3C implementation with more than one
32 * of these rtc blocks in */
34 static struct resource
*s3c_rtc_mem
;
36 static void __iomem
*s3c_rtc_base
;
37 static int s3c_rtc_alarmno
= NO_IRQ
;
38 static int s3c_rtc_tickno
= NO_IRQ
;
40 static DEFINE_SPINLOCK(s3c_rtc_pie_lock
);
44 static irqreturn_t
s3c_rtc_alarmirq(int irq
, void *id
)
46 struct rtc_device
*rdev
= id
;
48 rtc_update_irq(rdev
, 1, RTC_AF
| RTC_IRQF
);
52 static irqreturn_t
s3c_rtc_tickirq(int irq
, void *id
)
54 struct rtc_device
*rdev
= id
;
56 rtc_update_irq(rdev
, 1, RTC_PF
| RTC_IRQF
);
60 /* Update control registers */
61 static void s3c_rtc_setaie(int to
)
65 pr_debug("%s: aie=%d\n", __func__
, to
);
67 tmp
= readb(s3c_rtc_base
+ S3C2410_RTCALM
) & ~S3C2410_RTCALM_ALMEN
;
70 tmp
|= S3C2410_RTCALM_ALMEN
;
72 writeb(tmp
, s3c_rtc_base
+ S3C2410_RTCALM
);
75 static int s3c_rtc_setpie(struct device
*dev
, int enabled
)
79 pr_debug("%s: pie=%d\n", __func__
, enabled
);
81 spin_lock_irq(&s3c_rtc_pie_lock
);
82 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & ~S3C2410_TICNT_ENABLE
;
85 tmp
|= S3C2410_TICNT_ENABLE
;
87 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
88 spin_unlock_irq(&s3c_rtc_pie_lock
);
93 static int s3c_rtc_setfreq(struct device
*dev
, int freq
)
97 spin_lock_irq(&s3c_rtc_pie_lock
);
99 tmp
= readb(s3c_rtc_base
+ S3C2410_TICNT
) & S3C2410_TICNT_ENABLE
;
100 tmp
|= (128 / freq
)-1;
102 writeb(tmp
, s3c_rtc_base
+ S3C2410_TICNT
);
103 spin_unlock_irq(&s3c_rtc_pie_lock
);
108 /* Time read/write */
110 static int s3c_rtc_gettime(struct device
*dev
, struct rtc_time
*rtc_tm
)
112 unsigned int have_retried
= 0;
113 void __iomem
*base
= s3c_rtc_base
;
116 rtc_tm
->tm_min
= readb(base
+ S3C2410_RTCMIN
);
117 rtc_tm
->tm_hour
= readb(base
+ S3C2410_RTCHOUR
);
118 rtc_tm
->tm_mday
= readb(base
+ S3C2410_RTCDATE
);
119 rtc_tm
->tm_mon
= readb(base
+ S3C2410_RTCMON
);
120 rtc_tm
->tm_year
= readb(base
+ S3C2410_RTCYEAR
);
121 rtc_tm
->tm_sec
= readb(base
+ S3C2410_RTCSEC
);
123 /* the only way to work out wether the system was mid-update
124 * when we read it is to check the second counter, and if it
125 * is zero, then we re-try the entire read
128 if (rtc_tm
->tm_sec
== 0 && !have_retried
) {
133 pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
134 rtc_tm
->tm_year
, rtc_tm
->tm_mon
, rtc_tm
->tm_mday
,
135 rtc_tm
->tm_hour
, rtc_tm
->tm_min
, rtc_tm
->tm_sec
);
137 rtc_tm
->tm_sec
= bcd2bin(rtc_tm
->tm_sec
);
138 rtc_tm
->tm_min
= bcd2bin(rtc_tm
->tm_min
);
139 rtc_tm
->tm_hour
= bcd2bin(rtc_tm
->tm_hour
);
140 rtc_tm
->tm_mday
= bcd2bin(rtc_tm
->tm_mday
);
141 rtc_tm
->tm_mon
= bcd2bin(rtc_tm
->tm_mon
);
142 rtc_tm
->tm_year
= bcd2bin(rtc_tm
->tm_year
);
144 rtc_tm
->tm_year
+= 100;
150 static int s3c_rtc_settime(struct device
*dev
, struct rtc_time
*tm
)
152 void __iomem
*base
= s3c_rtc_base
;
153 int year
= tm
->tm_year
- 100;
155 pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
156 tm
->tm_year
, tm
->tm_mon
, tm
->tm_mday
,
157 tm
->tm_hour
, tm
->tm_min
, tm
->tm_sec
);
159 /* we get around y2k by simply not supporting it */
161 if (year
< 0 || year
>= 100) {
162 dev_err(dev
, "rtc only supports 100 years\n");
166 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_RTCSEC
);
167 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_RTCMIN
);
168 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_RTCHOUR
);
169 writeb(bin2bcd(tm
->tm_mday
), base
+ S3C2410_RTCDATE
);
170 writeb(bin2bcd(tm
->tm_mon
+ 1), base
+ S3C2410_RTCMON
);
171 writeb(bin2bcd(year
), base
+ S3C2410_RTCYEAR
);
176 static int s3c_rtc_getalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
178 struct rtc_time
*alm_tm
= &alrm
->time
;
179 void __iomem
*base
= s3c_rtc_base
;
182 alm_tm
->tm_sec
= readb(base
+ S3C2410_ALMSEC
);
183 alm_tm
->tm_min
= readb(base
+ S3C2410_ALMMIN
);
184 alm_tm
->tm_hour
= readb(base
+ S3C2410_ALMHOUR
);
185 alm_tm
->tm_mon
= readb(base
+ S3C2410_ALMMON
);
186 alm_tm
->tm_mday
= readb(base
+ S3C2410_ALMDATE
);
187 alm_tm
->tm_year
= readb(base
+ S3C2410_ALMYEAR
);
189 alm_en
= readb(base
+ S3C2410_RTCALM
);
191 alrm
->enabled
= (alm_en
& S3C2410_RTCALM_ALMEN
) ? 1 : 0;
193 pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
195 alm_tm
->tm_year
, alm_tm
->tm_mon
, alm_tm
->tm_mday
,
196 alm_tm
->tm_hour
, alm_tm
->tm_min
, alm_tm
->tm_sec
);
199 /* decode the alarm enable field */
201 if (alm_en
& S3C2410_RTCALM_SECEN
)
202 alm_tm
->tm_sec
= bcd2bin(alm_tm
->tm_sec
);
204 alm_tm
->tm_sec
= 0xff;
206 if (alm_en
& S3C2410_RTCALM_MINEN
)
207 alm_tm
->tm_min
= bcd2bin(alm_tm
->tm_min
);
209 alm_tm
->tm_min
= 0xff;
211 if (alm_en
& S3C2410_RTCALM_HOUREN
)
212 alm_tm
->tm_hour
= bcd2bin(alm_tm
->tm_hour
);
214 alm_tm
->tm_hour
= 0xff;
216 if (alm_en
& S3C2410_RTCALM_DAYEN
)
217 alm_tm
->tm_mday
= bcd2bin(alm_tm
->tm_mday
);
219 alm_tm
->tm_mday
= 0xff;
221 if (alm_en
& S3C2410_RTCALM_MONEN
) {
222 alm_tm
->tm_mon
= bcd2bin(alm_tm
->tm_mon
);
225 alm_tm
->tm_mon
= 0xff;
228 if (alm_en
& S3C2410_RTCALM_YEAREN
)
229 alm_tm
->tm_year
= bcd2bin(alm_tm
->tm_year
);
231 alm_tm
->tm_year
= 0xffff;
236 static int s3c_rtc_setalarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
238 struct rtc_time
*tm
= &alrm
->time
;
239 void __iomem
*base
= s3c_rtc_base
;
240 unsigned int alrm_en
;
242 pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
244 tm
->tm_mday
& 0xff, tm
->tm_mon
& 0xff, tm
->tm_year
& 0xff,
245 tm
->tm_hour
& 0xff, tm
->tm_min
& 0xff, tm
->tm_sec
);
248 alrm_en
= readb(base
+ S3C2410_RTCALM
) & S3C2410_RTCALM_ALMEN
;
249 writeb(0x00, base
+ S3C2410_RTCALM
);
251 if (tm
->tm_sec
< 60 && tm
->tm_sec
>= 0) {
252 alrm_en
|= S3C2410_RTCALM_SECEN
;
253 writeb(bin2bcd(tm
->tm_sec
), base
+ S3C2410_ALMSEC
);
256 if (tm
->tm_min
< 60 && tm
->tm_min
>= 0) {
257 alrm_en
|= S3C2410_RTCALM_MINEN
;
258 writeb(bin2bcd(tm
->tm_min
), base
+ S3C2410_ALMMIN
);
261 if (tm
->tm_hour
< 24 && tm
->tm_hour
>= 0) {
262 alrm_en
|= S3C2410_RTCALM_HOUREN
;
263 writeb(bin2bcd(tm
->tm_hour
), base
+ S3C2410_ALMHOUR
);
266 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en
);
268 writeb(alrm_en
, base
+ S3C2410_RTCALM
);
270 s3c_rtc_setaie(alrm
->enabled
);
273 enable_irq_wake(s3c_rtc_alarmno
);
275 disable_irq_wake(s3c_rtc_alarmno
);
280 static int s3c_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
282 unsigned int ticnt
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
284 seq_printf(seq
, "periodic_IRQ\t: %s\n",
285 (ticnt
& S3C2410_TICNT_ENABLE
) ? "yes" : "no" );
289 static int s3c_rtc_open(struct device
*dev
)
291 struct platform_device
*pdev
= to_platform_device(dev
);
292 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
295 ret
= request_irq(s3c_rtc_alarmno
, s3c_rtc_alarmirq
,
296 IRQF_DISABLED
, "s3c2410-rtc alarm", rtc_dev
);
299 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_alarmno
, ret
);
303 ret
= request_irq(s3c_rtc_tickno
, s3c_rtc_tickirq
,
304 IRQF_DISABLED
, "s3c2410-rtc tick", rtc_dev
);
307 dev_err(dev
, "IRQ%d error %d\n", s3c_rtc_tickno
, ret
);
314 free_irq(s3c_rtc_alarmno
, rtc_dev
);
318 static void s3c_rtc_release(struct device
*dev
)
320 struct platform_device
*pdev
= to_platform_device(dev
);
321 struct rtc_device
*rtc_dev
= platform_get_drvdata(pdev
);
323 /* do not clear AIE here, it may be needed for wake */
325 s3c_rtc_setpie(dev
, 0);
326 free_irq(s3c_rtc_alarmno
, rtc_dev
);
327 free_irq(s3c_rtc_tickno
, rtc_dev
);
330 static const struct rtc_class_ops s3c_rtcops
= {
331 .open
= s3c_rtc_open
,
332 .release
= s3c_rtc_release
,
333 .read_time
= s3c_rtc_gettime
,
334 .set_time
= s3c_rtc_settime
,
335 .read_alarm
= s3c_rtc_getalarm
,
336 .set_alarm
= s3c_rtc_setalarm
,
337 .irq_set_freq
= s3c_rtc_setfreq
,
338 .irq_set_state
= s3c_rtc_setpie
,
339 .proc
= s3c_rtc_proc
,
342 static void s3c_rtc_enable(struct platform_device
*pdev
, int en
)
344 void __iomem
*base
= s3c_rtc_base
;
347 if (s3c_rtc_base
== NULL
)
351 tmp
= readb(base
+ S3C2410_RTCCON
);
352 writeb(tmp
& ~S3C2410_RTCCON_RTCEN
, base
+ S3C2410_RTCCON
);
354 tmp
= readb(base
+ S3C2410_TICNT
);
355 writeb(tmp
& ~S3C2410_TICNT_ENABLE
, base
+ S3C2410_TICNT
);
357 /* re-enable the device, and check it is ok */
359 if ((readb(base
+S3C2410_RTCCON
) & S3C2410_RTCCON_RTCEN
) == 0){
360 dev_info(&pdev
->dev
, "rtc disabled, re-enabling\n");
362 tmp
= readb(base
+ S3C2410_RTCCON
);
363 writeb(tmp
|S3C2410_RTCCON_RTCEN
, base
+S3C2410_RTCCON
);
366 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CNTSEL
)){
367 dev_info(&pdev
->dev
, "removing RTCCON_CNTSEL\n");
369 tmp
= readb(base
+ S3C2410_RTCCON
);
370 writeb(tmp
& ~S3C2410_RTCCON_CNTSEL
, base
+S3C2410_RTCCON
);
373 if ((readb(base
+ S3C2410_RTCCON
) & S3C2410_RTCCON_CLKRST
)){
374 dev_info(&pdev
->dev
, "removing RTCCON_CLKRST\n");
376 tmp
= readb(base
+ S3C2410_RTCCON
);
377 writeb(tmp
& ~S3C2410_RTCCON_CLKRST
, base
+S3C2410_RTCCON
);
382 static int __devexit
s3c_rtc_remove(struct platform_device
*dev
)
384 struct rtc_device
*rtc
= platform_get_drvdata(dev
);
386 platform_set_drvdata(dev
, NULL
);
387 rtc_device_unregister(rtc
);
389 s3c_rtc_setpie(&dev
->dev
, 0);
392 iounmap(s3c_rtc_base
);
393 release_resource(s3c_rtc_mem
);
399 static int __devinit
s3c_rtc_probe(struct platform_device
*pdev
)
401 struct rtc_device
*rtc
;
402 struct resource
*res
;
405 pr_debug("%s: probe=%p\n", __func__
, pdev
);
409 s3c_rtc_tickno
= platform_get_irq(pdev
, 1);
410 if (s3c_rtc_tickno
< 0) {
411 dev_err(&pdev
->dev
, "no irq for rtc tick\n");
415 s3c_rtc_alarmno
= platform_get_irq(pdev
, 0);
416 if (s3c_rtc_alarmno
< 0) {
417 dev_err(&pdev
->dev
, "no irq for alarm\n");
421 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
422 s3c_rtc_tickno
, s3c_rtc_alarmno
);
424 /* get the memory region */
426 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
428 dev_err(&pdev
->dev
, "failed to get memory region resource\n");
432 s3c_rtc_mem
= request_mem_region(res
->start
,
433 res
->end
-res
->start
+1,
436 if (s3c_rtc_mem
== NULL
) {
437 dev_err(&pdev
->dev
, "failed to reserve memory region\n");
442 s3c_rtc_base
= ioremap(res
->start
, res
->end
- res
->start
+ 1);
443 if (s3c_rtc_base
== NULL
) {
444 dev_err(&pdev
->dev
, "failed ioremap()\n");
449 /* check to see if everything is setup correctly */
451 s3c_rtc_enable(pdev
, 1);
453 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
454 readb(s3c_rtc_base
+ S3C2410_RTCCON
));
456 s3c_rtc_setfreq(&pdev
->dev
, 1);
458 /* register RTC and exit */
460 rtc
= rtc_device_register("s3c", &pdev
->dev
, &s3c_rtcops
,
464 dev_err(&pdev
->dev
, "cannot attach rtc\n");
469 rtc
->max_user_freq
= 128;
471 platform_set_drvdata(pdev
, rtc
);
475 s3c_rtc_enable(pdev
, 0);
476 iounmap(s3c_rtc_base
);
479 release_resource(s3c_rtc_mem
);
487 /* RTC Power management control */
489 static int ticnt_save
;
491 static int s3c_rtc_suspend(struct platform_device
*pdev
, pm_message_t state
)
493 /* save TICNT for anyone using periodic interrupts */
494 ticnt_save
= readb(s3c_rtc_base
+ S3C2410_TICNT
);
495 s3c_rtc_enable(pdev
, 0);
499 static int s3c_rtc_resume(struct platform_device
*pdev
)
501 s3c_rtc_enable(pdev
, 1);
502 writeb(ticnt_save
, s3c_rtc_base
+ S3C2410_TICNT
);
506 #define s3c_rtc_suspend NULL
507 #define s3c_rtc_resume NULL
510 static struct platform_driver s3c2410_rtcdrv
= {
511 .probe
= s3c_rtc_probe
,
512 .remove
= __devexit_p(s3c_rtc_remove
),
513 .suspend
= s3c_rtc_suspend
,
514 .resume
= s3c_rtc_resume
,
516 .name
= "s3c2410-rtc",
517 .owner
= THIS_MODULE
,
521 static char __initdata banner
[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
523 static int __init
s3c_rtc_init(void)
526 return platform_driver_register(&s3c2410_rtcdrv
);
529 static void __exit
s3c_rtc_exit(void)
531 platform_driver_unregister(&s3c2410_rtcdrv
);
534 module_init(s3c_rtc_init
);
535 module_exit(s3c_rtc_exit
);
537 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
538 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
539 MODULE_LICENSE("GPL");
540 MODULE_ALIAS("platform:s3c2410-rtc");