2 * SuperH On-Chip RTC Support
4 * Copyright (C) 2006, 2007 Paul Mundt
5 * Copyright (C) 2006 Jamie Lenehan
7 * Based on the old arch/sh/kernel/cpu/rtc.c by:
9 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
10 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
12 * This file is subject to the terms and conditions of the GNU General Public
13 * License. See the file "COPYING" in the main directory of this archive
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/bcd.h>
19 #include <linux/rtc.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/seq_file.h>
23 #include <linux/interrupt.h>
24 #include <linux/spinlock.h>
28 #define DRV_NAME "sh-rtc"
29 #define DRV_VERSION "0.1.3"
32 #define rtc_reg_size sizeof(u16)
33 #define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */
34 #define RTC_DEF_CAPABILITIES 0UL
35 #elif defined(CONFIG_CPU_SH4)
36 #define rtc_reg_size sizeof(u32)
37 #define RTC_BIT_INVERTED 0x40 /* bug on SH7750, SH7750S */
38 #define RTC_DEF_CAPABILITIES RTC_CAP_4_DIGIT_YEAR
41 #define RTC_REG(r) ((r) * rtc_reg_size)
43 #define R64CNT RTC_REG(0)
45 #define RSECCNT RTC_REG(1) /* RTC sec */
46 #define RMINCNT RTC_REG(2) /* RTC min */
47 #define RHRCNT RTC_REG(3) /* RTC hour */
48 #define RWKCNT RTC_REG(4) /* RTC week */
49 #define RDAYCNT RTC_REG(5) /* RTC day */
50 #define RMONCNT RTC_REG(6) /* RTC month */
51 #define RYRCNT RTC_REG(7) /* RTC year */
52 #define RSECAR RTC_REG(8) /* ALARM sec */
53 #define RMINAR RTC_REG(9) /* ALARM min */
54 #define RHRAR RTC_REG(10) /* ALARM hour */
55 #define RWKAR RTC_REG(11) /* ALARM week */
56 #define RDAYAR RTC_REG(12) /* ALARM day */
57 #define RMONAR RTC_REG(13) /* ALARM month */
58 #define RCR1 RTC_REG(14) /* Control */
59 #define RCR2 RTC_REG(15) /* Control */
61 /* ALARM Bits - or with BCD encoded value */
62 #define AR_ENB 0x80 /* Enable for alarm cmp */
65 #define RCR1_CF 0x80 /* Carry Flag */
66 #define RCR1_CIE 0x10 /* Carry Interrupt Enable */
67 #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
68 #define RCR1_AF 0x01 /* Alarm Flag */
71 #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
72 #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
73 #define RCR2_RTCEN 0x08 /* ENable RTC */
74 #define RCR2_ADJ 0x04 /* ADJustment (30-second) */
75 #define RCR2_RESET 0x02 /* Reset bit */
76 #define RCR2_START 0x01 /* Start bit */
79 void __iomem
*regbase
;
80 unsigned long regsize
;
82 unsigned int alarm_irq
, periodic_irq
, carry_irq
;
83 struct rtc_device
*rtc_dev
;
86 unsigned long capabilities
; /* See asm-sh/rtc.h for cap bits */
89 static irqreturn_t
sh_rtc_interrupt(int irq
, void *dev_id
)
91 struct platform_device
*pdev
= to_platform_device(dev_id
);
92 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
93 unsigned int tmp
, events
= 0;
95 spin_lock(&rtc
->lock
);
97 tmp
= readb(rtc
->regbase
+ RCR1
);
100 if (rtc
->rearm_aie
) {
102 tmp
&= ~RCR1_AF
; /* try to clear AF again */
104 tmp
|= RCR1_AIE
; /* AF has cleared, rearm IRQ */
109 writeb(tmp
, rtc
->regbase
+ RCR1
);
111 rtc_update_irq(rtc
->rtc_dev
, 1, events
);
113 spin_unlock(&rtc
->lock
);
118 static irqreturn_t
sh_rtc_alarm(int irq
, void *dev_id
)
120 struct platform_device
*pdev
= to_platform_device(dev_id
);
121 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
122 unsigned int tmp
, events
= 0;
124 spin_lock(&rtc
->lock
);
126 tmp
= readb(rtc
->regbase
+ RCR1
);
129 * If AF is set then the alarm has triggered. If we clear AF while
130 * the alarm time still matches the RTC time then AF will
131 * immediately be set again, and if AIE is enabled then the alarm
132 * interrupt will immediately be retrigger. So we clear AIE here
133 * and use rtc->rearm_aie so that the carry interrupt will keep
134 * trying to clear AF and once it stays cleared it'll re-enable
138 events
|= RTC_AF
| RTC_IRQF
;
140 tmp
&= ~(RCR1_AF
|RCR1_AIE
);
142 writeb(tmp
, rtc
->regbase
+ RCR1
);
146 rtc_update_irq(rtc
->rtc_dev
, 1, events
);
149 spin_unlock(&rtc
->lock
);
153 static irqreturn_t
sh_rtc_periodic(int irq
, void *dev_id
)
155 struct platform_device
*pdev
= to_platform_device(dev_id
);
156 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
158 spin_lock(&rtc
->lock
);
160 rtc_update_irq(rtc
->rtc_dev
, 1, RTC_PF
| RTC_IRQF
);
162 spin_unlock(&rtc
->lock
);
167 static inline void sh_rtc_setpie(struct device
*dev
, unsigned int enable
)
169 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
172 spin_lock_irq(&rtc
->lock
);
174 tmp
= readb(rtc
->regbase
+ RCR2
);
177 tmp
&= ~RCR2_PESMASK
;
178 tmp
|= RCR2_PEF
| (2 << 4);
180 tmp
&= ~(RCR2_PESMASK
| RCR2_PEF
);
182 writeb(tmp
, rtc
->regbase
+ RCR2
);
184 spin_unlock_irq(&rtc
->lock
);
187 static inline void sh_rtc_setaie(struct device
*dev
, unsigned int enable
)
189 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
192 spin_lock_irq(&rtc
->lock
);
194 tmp
= readb(rtc
->regbase
+ RCR1
);
199 } else if (rtc
->rearm_aie
== 0)
202 writeb(tmp
, rtc
->regbase
+ RCR1
);
204 spin_unlock_irq(&rtc
->lock
);
207 static int sh_rtc_open(struct device
*dev
)
209 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
213 tmp
= readb(rtc
->regbase
+ RCR1
);
216 writeb(tmp
, rtc
->regbase
+ RCR1
);
218 ret
= request_irq(rtc
->periodic_irq
, sh_rtc_periodic
, IRQF_DISABLED
,
219 "sh-rtc period", dev
);
221 dev_err(dev
, "request period IRQ failed with %d, IRQ %d\n",
222 ret
, rtc
->periodic_irq
);
226 ret
= request_irq(rtc
->carry_irq
, sh_rtc_interrupt
, IRQF_DISABLED
,
227 "sh-rtc carry", dev
);
229 dev_err(dev
, "request carry IRQ failed with %d, IRQ %d\n",
230 ret
, rtc
->carry_irq
);
231 free_irq(rtc
->periodic_irq
, dev
);
235 ret
= request_irq(rtc
->alarm_irq
, sh_rtc_alarm
, IRQF_DISABLED
,
236 "sh-rtc alarm", dev
);
238 dev_err(dev
, "request alarm IRQ failed with %d, IRQ %d\n",
239 ret
, rtc
->alarm_irq
);
246 free_irq(rtc
->carry_irq
, dev
);
248 free_irq(rtc
->periodic_irq
, dev
);
253 static void sh_rtc_release(struct device
*dev
)
255 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
257 sh_rtc_setpie(dev
, 0);
258 sh_rtc_setaie(dev
, 0);
260 free_irq(rtc
->periodic_irq
, dev
);
261 free_irq(rtc
->carry_irq
, dev
);
262 free_irq(rtc
->alarm_irq
, dev
);
265 static int sh_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
267 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
270 tmp
= readb(rtc
->regbase
+ RCR1
);
271 seq_printf(seq
, "carry_IRQ\t: %s\n",
272 (tmp
& RCR1_CIE
) ? "yes" : "no");
274 tmp
= readb(rtc
->regbase
+ RCR2
);
275 seq_printf(seq
, "periodic_IRQ\t: %s\n",
276 (tmp
& RCR2_PEF
) ? "yes" : "no");
281 static int sh_rtc_ioctl(struct device
*dev
, unsigned int cmd
, unsigned long arg
)
283 unsigned int ret
= -ENOIOCTLCMD
;
288 sh_rtc_setpie(dev
, cmd
== RTC_PIE_ON
);
293 sh_rtc_setaie(dev
, cmd
== RTC_AIE_ON
);
301 static int sh_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
303 struct platform_device
*pdev
= to_platform_device(dev
);
304 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
305 unsigned int sec128
, sec2
, yr
, yr100
, cf_bit
;
310 spin_lock_irq(&rtc
->lock
);
312 tmp
= readb(rtc
->regbase
+ RCR1
);
313 tmp
&= ~RCR1_CF
; /* Clear CF-bit */
315 writeb(tmp
, rtc
->regbase
+ RCR1
);
317 sec128
= readb(rtc
->regbase
+ R64CNT
);
319 tm
->tm_sec
= BCD2BIN(readb(rtc
->regbase
+ RSECCNT
));
320 tm
->tm_min
= BCD2BIN(readb(rtc
->regbase
+ RMINCNT
));
321 tm
->tm_hour
= BCD2BIN(readb(rtc
->regbase
+ RHRCNT
));
322 tm
->tm_wday
= BCD2BIN(readb(rtc
->regbase
+ RWKCNT
));
323 tm
->tm_mday
= BCD2BIN(readb(rtc
->regbase
+ RDAYCNT
));
324 tm
->tm_mon
= BCD2BIN(readb(rtc
->regbase
+ RMONCNT
)) - 1;
326 if (rtc
->capabilities
& RTC_CAP_4_DIGIT_YEAR
) {
327 yr
= readw(rtc
->regbase
+ RYRCNT
);
328 yr100
= BCD2BIN(yr
>> 8);
331 yr
= readb(rtc
->regbase
+ RYRCNT
);
332 yr100
= BCD2BIN((yr
== 0x99) ? 0x19 : 0x20);
335 tm
->tm_year
= (yr100
* 100 + BCD2BIN(yr
)) - 1900;
337 sec2
= readb(rtc
->regbase
+ R64CNT
);
338 cf_bit
= readb(rtc
->regbase
+ RCR1
) & RCR1_CF
;
340 spin_unlock_irq(&rtc
->lock
);
341 } while (cf_bit
!= 0 || ((sec128
^ sec2
) & RTC_BIT_INVERTED
) != 0);
343 #if RTC_BIT_INVERTED != 0
344 if ((sec128
& RTC_BIT_INVERTED
))
348 dev_dbg(dev
, "%s: tm is secs=%d, mins=%d, hours=%d, "
349 "mday=%d, mon=%d, year=%d, wday=%d\n",
351 tm
->tm_sec
, tm
->tm_min
, tm
->tm_hour
,
352 tm
->tm_mday
, tm
->tm_mon
+ 1, tm
->tm_year
, tm
->tm_wday
);
354 if (rtc_valid_tm(tm
) < 0) {
355 dev_err(dev
, "invalid date\n");
356 rtc_time_to_tm(0, tm
);
362 static int sh_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
364 struct platform_device
*pdev
= to_platform_device(dev
);
365 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
369 spin_lock_irq(&rtc
->lock
);
371 /* Reset pre-scaler & stop RTC */
372 tmp
= readb(rtc
->regbase
+ RCR2
);
375 writeb(tmp
, rtc
->regbase
+ RCR2
);
377 writeb(BIN2BCD(tm
->tm_sec
), rtc
->regbase
+ RSECCNT
);
378 writeb(BIN2BCD(tm
->tm_min
), rtc
->regbase
+ RMINCNT
);
379 writeb(BIN2BCD(tm
->tm_hour
), rtc
->regbase
+ RHRCNT
);
380 writeb(BIN2BCD(tm
->tm_wday
), rtc
->regbase
+ RWKCNT
);
381 writeb(BIN2BCD(tm
->tm_mday
), rtc
->regbase
+ RDAYCNT
);
382 writeb(BIN2BCD(tm
->tm_mon
+ 1), rtc
->regbase
+ RMONCNT
);
384 if (rtc
->capabilities
& RTC_CAP_4_DIGIT_YEAR
) {
385 year
= (BIN2BCD((tm
->tm_year
+ 1900) / 100) << 8) |
386 BIN2BCD(tm
->tm_year
% 100);
387 writew(year
, rtc
->regbase
+ RYRCNT
);
389 year
= tm
->tm_year
% 100;
390 writeb(BIN2BCD(year
), rtc
->regbase
+ RYRCNT
);
394 tmp
= readb(rtc
->regbase
+ RCR2
);
396 tmp
|= RCR2_RTCEN
| RCR2_START
;
397 writeb(tmp
, rtc
->regbase
+ RCR2
);
399 spin_unlock_irq(&rtc
->lock
);
404 static inline int sh_rtc_read_alarm_value(struct sh_rtc
*rtc
, int reg_off
)
407 int value
= 0xff; /* return 0xff for ignored values */
409 byte
= readb(rtc
->regbase
+ reg_off
);
411 byte
&= ~AR_ENB
; /* strip the enable bit */
412 value
= BCD2BIN(byte
);
418 static int sh_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*wkalrm
)
420 struct platform_device
*pdev
= to_platform_device(dev
);
421 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
422 struct rtc_time
* tm
= &wkalrm
->time
;
424 spin_lock_irq(&rtc
->lock
);
426 tm
->tm_sec
= sh_rtc_read_alarm_value(rtc
, RSECAR
);
427 tm
->tm_min
= sh_rtc_read_alarm_value(rtc
, RMINAR
);
428 tm
->tm_hour
= sh_rtc_read_alarm_value(rtc
, RHRAR
);
429 tm
->tm_wday
= sh_rtc_read_alarm_value(rtc
, RWKAR
);
430 tm
->tm_mday
= sh_rtc_read_alarm_value(rtc
, RDAYAR
);
431 tm
->tm_mon
= sh_rtc_read_alarm_value(rtc
, RMONAR
);
433 tm
->tm_mon
-= 1; /* RTC is 1-12, tm_mon is 0-11 */
434 tm
->tm_year
= 0xffff;
436 wkalrm
->enabled
= (readb(rtc
->regbase
+ RCR1
) & RCR1_AIE
) ? 1 : 0;
438 spin_unlock_irq(&rtc
->lock
);
443 static inline void sh_rtc_write_alarm_value(struct sh_rtc
*rtc
,
444 int value
, int reg_off
)
446 /* < 0 for a value that is ignored */
448 writeb(0, rtc
->regbase
+ reg_off
);
450 writeb(BIN2BCD(value
) | AR_ENB
, rtc
->regbase
+ reg_off
);
453 static int sh_rtc_check_alarm(struct rtc_time
* tm
)
456 * The original rtc says anything > 0xc0 is "don't care" or "match
457 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
458 * The original rtc doesn't support years - some things use -1 and
459 * some 0xffff. We use -1 to make out tests easier.
461 if (tm
->tm_year
== 0xffff)
463 if (tm
->tm_mon
>= 0xff)
465 if (tm
->tm_mday
>= 0xff)
467 if (tm
->tm_wday
>= 0xff)
469 if (tm
->tm_hour
>= 0xff)
471 if (tm
->tm_min
>= 0xff)
473 if (tm
->tm_sec
>= 0xff)
476 if (tm
->tm_year
> 9999 ||
478 tm
->tm_mday
== 0 || tm
->tm_mday
>= 32 ||
488 static int sh_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*wkalrm
)
490 struct platform_device
*pdev
= to_platform_device(dev
);
491 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
493 struct rtc_time
*tm
= &wkalrm
->time
;
496 err
= sh_rtc_check_alarm(tm
);
497 if (unlikely(err
< 0))
500 spin_lock_irq(&rtc
->lock
);
502 /* disable alarm interrupt and clear the alarm flag */
503 rcr1
= readb(rtc
->regbase
+ RCR1
);
504 rcr1
&= ~(RCR1_AF
|RCR1_AIE
);
505 writeb(rcr1
, rtc
->regbase
+ RCR1
);
510 sh_rtc_write_alarm_value(rtc
, tm
->tm_sec
, RSECAR
);
511 sh_rtc_write_alarm_value(rtc
, tm
->tm_min
, RMINAR
);
512 sh_rtc_write_alarm_value(rtc
, tm
->tm_hour
, RHRAR
);
513 sh_rtc_write_alarm_value(rtc
, tm
->tm_wday
, RWKAR
);
514 sh_rtc_write_alarm_value(rtc
, tm
->tm_mday
, RDAYAR
);
518 sh_rtc_write_alarm_value(rtc
, mon
, RMONAR
);
520 if (wkalrm
->enabled
) {
522 writeb(rcr1
, rtc
->regbase
+ RCR1
);
525 spin_unlock_irq(&rtc
->lock
);
530 static struct rtc_class_ops sh_rtc_ops
= {
532 .release
= sh_rtc_release
,
533 .ioctl
= sh_rtc_ioctl
,
534 .read_time
= sh_rtc_read_time
,
535 .set_time
= sh_rtc_set_time
,
536 .read_alarm
= sh_rtc_read_alarm
,
537 .set_alarm
= sh_rtc_set_alarm
,
541 static int __devinit
sh_rtc_probe(struct platform_device
*pdev
)
544 struct resource
*res
;
547 rtc
= kzalloc(sizeof(struct sh_rtc
), GFP_KERNEL
);
551 spin_lock_init(&rtc
->lock
);
553 rtc
->periodic_irq
= platform_get_irq(pdev
, 0);
554 if (unlikely(rtc
->periodic_irq
< 0)) {
555 dev_err(&pdev
->dev
, "No IRQ for period\n");
559 rtc
->carry_irq
= platform_get_irq(pdev
, 1);
560 if (unlikely(rtc
->carry_irq
< 0)) {
561 dev_err(&pdev
->dev
, "No IRQ for carry\n");
565 rtc
->alarm_irq
= platform_get_irq(pdev
, 2);
566 if (unlikely(rtc
->alarm_irq
< 0)) {
567 dev_err(&pdev
->dev
, "No IRQ for alarm\n");
571 res
= platform_get_resource(pdev
, IORESOURCE_IO
, 0);
572 if (unlikely(res
== NULL
)) {
573 dev_err(&pdev
->dev
, "No IO resource\n");
577 rtc
->regsize
= res
->end
- res
->start
+ 1;
579 rtc
->res
= request_mem_region(res
->start
, rtc
->regsize
, pdev
->name
);
580 if (unlikely(!rtc
->res
)) {
585 rtc
->regbase
= (void __iomem
*)rtc
->res
->start
;
586 if (unlikely(!rtc
->regbase
)) {
591 rtc
->rtc_dev
= rtc_device_register("sh", &pdev
->dev
,
592 &sh_rtc_ops
, THIS_MODULE
);
593 if (IS_ERR(rtc
->rtc_dev
)) {
594 ret
= PTR_ERR(rtc
->rtc_dev
);
598 rtc
->capabilities
= RTC_DEF_CAPABILITIES
;
599 if (pdev
->dev
.platform_data
) {
600 struct sh_rtc_platform_info
*pinfo
= pdev
->dev
.platform_data
;
603 * Some CPUs have special capabilities in addition to the
604 * default set. Add those in here.
606 rtc
->capabilities
|= pinfo
->capabilities
;
609 platform_set_drvdata(pdev
, rtc
);
614 release_resource(rtc
->res
);
621 static int __devexit
sh_rtc_remove(struct platform_device
*pdev
)
623 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
625 if (likely(rtc
->rtc_dev
))
626 rtc_device_unregister(rtc
->rtc_dev
);
628 sh_rtc_setpie(&pdev
->dev
, 0);
629 sh_rtc_setaie(&pdev
->dev
, 0);
631 release_resource(rtc
->res
);
633 platform_set_drvdata(pdev
, NULL
);
639 static struct platform_driver sh_rtc_platform_driver
= {
642 .owner
= THIS_MODULE
,
644 .probe
= sh_rtc_probe
,
645 .remove
= __devexit_p(sh_rtc_remove
),
648 static int __init
sh_rtc_init(void)
650 return platform_driver_register(&sh_rtc_platform_driver
);
653 static void __exit
sh_rtc_exit(void)
655 platform_driver_unregister(&sh_rtc_platform_driver
);
658 module_init(sh_rtc_init
);
659 module_exit(sh_rtc_exit
);
661 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
662 MODULE_VERSION(DRV_VERSION
);
663 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
664 MODULE_LICENSE("GPL");