2 * SuperH On-Chip RTC Support
4 * Copyright (C) 2006 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>
27 #define DRV_NAME "sh-rtc"
28 #define DRV_VERSION "0.1.2"
31 #define rtc_reg_size sizeof(u16)
32 #define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */
33 #elif defined(CONFIG_CPU_SH4)
34 #define rtc_reg_size sizeof(u32)
35 #define RTC_BIT_INVERTED 0x40 /* bug on SH7750, SH7750S */
38 #define RTC_REG(r) ((r) * rtc_reg_size)
40 #define R64CNT RTC_REG(0)
42 #define RSECCNT RTC_REG(1) /* RTC sec */
43 #define RMINCNT RTC_REG(2) /* RTC min */
44 #define RHRCNT RTC_REG(3) /* RTC hour */
45 #define RWKCNT RTC_REG(4) /* RTC week */
46 #define RDAYCNT RTC_REG(5) /* RTC day */
47 #define RMONCNT RTC_REG(6) /* RTC month */
48 #define RYRCNT RTC_REG(7) /* RTC year */
49 #define RSECAR RTC_REG(8) /* ALARM sec */
50 #define RMINAR RTC_REG(9) /* ALARM min */
51 #define RHRAR RTC_REG(10) /* ALARM hour */
52 #define RWKAR RTC_REG(11) /* ALARM week */
53 #define RDAYAR RTC_REG(12) /* ALARM day */
54 #define RMONAR RTC_REG(13) /* ALARM month */
55 #define RCR1 RTC_REG(14) /* Control */
56 #define RCR2 RTC_REG(15) /* Control */
58 /* ALARM Bits - or with BCD encoded value */
59 #define AR_ENB 0x80 /* Enable for alarm cmp */
62 #define RCR1_CF 0x80 /* Carry Flag */
63 #define RCR1_CIE 0x10 /* Carry Interrupt Enable */
64 #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
65 #define RCR1_AF 0x01 /* Alarm Flag */
68 #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
69 #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
70 #define RCR2_RTCEN 0x08 /* ENable RTC */
71 #define RCR2_ADJ 0x04 /* ADJustment (30-second) */
72 #define RCR2_RESET 0x02 /* Reset bit */
73 #define RCR2_START 0x01 /* Start bit */
76 void __iomem
*regbase
;
77 unsigned long regsize
;
79 unsigned int alarm_irq
, periodic_irq
, carry_irq
;
80 struct rtc_device
*rtc_dev
;
85 static irqreturn_t
sh_rtc_interrupt(int irq
, void *dev_id
)
87 struct platform_device
*pdev
= to_platform_device(dev_id
);
88 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
89 unsigned int tmp
, events
= 0;
91 spin_lock(&rtc
->lock
);
93 tmp
= readb(rtc
->regbase
+ RCR1
);
98 tmp
&= ~RCR1_AF
; /* try to clear AF again */
100 tmp
|= RCR1_AIE
; /* AF has cleared, rearm IRQ */
105 writeb(tmp
, rtc
->regbase
+ RCR1
);
107 rtc_update_irq(rtc
->rtc_dev
, 1, events
);
109 spin_unlock(&rtc
->lock
);
114 static irqreturn_t
sh_rtc_alarm(int irq
, void *dev_id
)
116 struct platform_device
*pdev
= to_platform_device(dev_id
);
117 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
118 unsigned int tmp
, events
= 0;
120 spin_lock(&rtc
->lock
);
122 tmp
= readb(rtc
->regbase
+ RCR1
);
125 * If AF is set then the alarm has triggered. If we clear AF while
126 * the alarm time still matches the RTC time then AF will
127 * immediately be set again, and if AIE is enabled then the alarm
128 * interrupt will immediately be retrigger. So we clear AIE here
129 * and use rtc->rearm_aie so that the carry interrupt will keep
130 * trying to clear AF and once it stays cleared it'll re-enable
134 events
|= RTC_AF
| RTC_IRQF
;
136 tmp
&= ~(RCR1_AF
|RCR1_AIE
);
138 writeb(tmp
, rtc
->regbase
+ RCR1
);
142 rtc_update_irq(rtc
->rtc_dev
, 1, events
);
145 spin_unlock(&rtc
->lock
);
149 static irqreturn_t
sh_rtc_periodic(int irq
, void *dev_id
)
151 struct platform_device
*pdev
= to_platform_device(dev_id
);
152 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
154 spin_lock(&rtc
->lock
);
156 rtc_update_irq(rtc
->rtc_dev
, 1, RTC_PF
| RTC_IRQF
);
158 spin_unlock(&rtc
->lock
);
163 static inline void sh_rtc_setpie(struct device
*dev
, unsigned int enable
)
165 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
168 spin_lock_irq(&rtc
->lock
);
170 tmp
= readb(rtc
->regbase
+ RCR2
);
173 tmp
&= ~RCR2_PESMASK
;
174 tmp
|= RCR2_PEF
| (2 << 4);
176 tmp
&= ~(RCR2_PESMASK
| RCR2_PEF
);
178 writeb(tmp
, rtc
->regbase
+ RCR2
);
180 spin_unlock_irq(&rtc
->lock
);
183 static inline void sh_rtc_setaie(struct device
*dev
, unsigned int enable
)
185 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
188 spin_lock_irq(&rtc
->lock
);
190 tmp
= readb(rtc
->regbase
+ RCR1
);
195 } else if (rtc
->rearm_aie
== 0)
198 writeb(tmp
, rtc
->regbase
+ RCR1
);
200 spin_unlock_irq(&rtc
->lock
);
203 static int sh_rtc_open(struct device
*dev
)
205 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
209 tmp
= readb(rtc
->regbase
+ RCR1
);
212 writeb(tmp
, rtc
->regbase
+ RCR1
);
214 ret
= request_irq(rtc
->periodic_irq
, sh_rtc_periodic
, IRQF_DISABLED
,
215 "sh-rtc period", dev
);
217 dev_err(dev
, "request period IRQ failed with %d, IRQ %d\n",
218 ret
, rtc
->periodic_irq
);
222 ret
= request_irq(rtc
->carry_irq
, sh_rtc_interrupt
, IRQF_DISABLED
,
223 "sh-rtc carry", dev
);
225 dev_err(dev
, "request carry IRQ failed with %d, IRQ %d\n",
226 ret
, rtc
->carry_irq
);
227 free_irq(rtc
->periodic_irq
, dev
);
231 ret
= request_irq(rtc
->alarm_irq
, sh_rtc_alarm
, IRQF_DISABLED
,
232 "sh-rtc alarm", dev
);
234 dev_err(dev
, "request alarm IRQ failed with %d, IRQ %d\n",
235 ret
, rtc
->alarm_irq
);
242 free_irq(rtc
->carry_irq
, dev
);
244 free_irq(rtc
->periodic_irq
, dev
);
249 static void sh_rtc_release(struct device
*dev
)
251 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
253 sh_rtc_setpie(dev
, 0);
254 sh_rtc_setaie(dev
, 0);
256 free_irq(rtc
->periodic_irq
, dev
);
257 free_irq(rtc
->carry_irq
, dev
);
258 free_irq(rtc
->alarm_irq
, dev
);
261 static int sh_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
263 struct sh_rtc
*rtc
= dev_get_drvdata(dev
);
266 tmp
= readb(rtc
->regbase
+ RCR1
);
267 seq_printf(seq
, "carry_IRQ\t: %s\n",
268 (tmp
& RCR1_CIE
) ? "yes" : "no");
270 tmp
= readb(rtc
->regbase
+ RCR2
);
271 seq_printf(seq
, "periodic_IRQ\t: %s\n",
272 (tmp
& RCR2_PEF
) ? "yes" : "no");
277 static int sh_rtc_ioctl(struct device
*dev
, unsigned int cmd
, unsigned long arg
)
279 unsigned int ret
= -ENOIOCTLCMD
;
284 sh_rtc_setpie(dev
, cmd
== RTC_PIE_ON
);
289 sh_rtc_setaie(dev
, cmd
== RTC_AIE_ON
);
297 static int sh_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
299 struct platform_device
*pdev
= to_platform_device(dev
);
300 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
301 unsigned int sec128
, sec2
, yr
, yr100
, cf_bit
;
306 spin_lock_irq(&rtc
->lock
);
308 tmp
= readb(rtc
->regbase
+ RCR1
);
309 tmp
&= ~RCR1_CF
; /* Clear CF-bit */
311 writeb(tmp
, rtc
->regbase
+ RCR1
);
313 sec128
= readb(rtc
->regbase
+ R64CNT
);
315 tm
->tm_sec
= BCD2BIN(readb(rtc
->regbase
+ RSECCNT
));
316 tm
->tm_min
= BCD2BIN(readb(rtc
->regbase
+ RMINCNT
));
317 tm
->tm_hour
= BCD2BIN(readb(rtc
->regbase
+ RHRCNT
));
318 tm
->tm_wday
= BCD2BIN(readb(rtc
->regbase
+ RWKCNT
));
319 tm
->tm_mday
= BCD2BIN(readb(rtc
->regbase
+ RDAYCNT
));
320 tm
->tm_mon
= BCD2BIN(readb(rtc
->regbase
+ RMONCNT
)) - 1;
322 #if defined(CONFIG_CPU_SH4)
323 yr
= readw(rtc
->regbase
+ RYRCNT
);
324 yr100
= BCD2BIN(yr
>> 8);
327 yr
= readb(rtc
->regbase
+ RYRCNT
);
328 yr100
= BCD2BIN((yr
== 0x99) ? 0x19 : 0x20);
331 tm
->tm_year
= (yr100
* 100 + BCD2BIN(yr
)) - 1900;
333 sec2
= readb(rtc
->regbase
+ R64CNT
);
334 cf_bit
= readb(rtc
->regbase
+ RCR1
) & RCR1_CF
;
336 spin_unlock_irq(&rtc
->lock
);
337 } while (cf_bit
!= 0 || ((sec128
^ sec2
) & RTC_BIT_INVERTED
) != 0);
339 #if RTC_BIT_INVERTED != 0
340 if ((sec128
& RTC_BIT_INVERTED
))
344 dev_dbg(dev
, "%s: tm is secs=%d, mins=%d, hours=%d, "
345 "mday=%d, mon=%d, year=%d, wday=%d\n",
347 tm
->tm_sec
, tm
->tm_min
, tm
->tm_hour
,
348 tm
->tm_mday
, tm
->tm_mon
+ 1, tm
->tm_year
, tm
->tm_wday
);
350 if (rtc_valid_tm(tm
) < 0)
351 dev_err(dev
, "invalid date\n");
356 static int sh_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
358 struct platform_device
*pdev
= to_platform_device(dev
);
359 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
363 spin_lock_irq(&rtc
->lock
);
365 /* Reset pre-scaler & stop RTC */
366 tmp
= readb(rtc
->regbase
+ RCR2
);
368 writeb(tmp
, rtc
->regbase
+ RCR2
);
370 writeb(BIN2BCD(tm
->tm_sec
), rtc
->regbase
+ RSECCNT
);
371 writeb(BIN2BCD(tm
->tm_min
), rtc
->regbase
+ RMINCNT
);
372 writeb(BIN2BCD(tm
->tm_hour
), rtc
->regbase
+ RHRCNT
);
373 writeb(BIN2BCD(tm
->tm_wday
), rtc
->regbase
+ RWKCNT
);
374 writeb(BIN2BCD(tm
->tm_mday
), rtc
->regbase
+ RDAYCNT
);
375 writeb(BIN2BCD(tm
->tm_mon
+ 1), rtc
->regbase
+ RMONCNT
);
377 #ifdef CONFIG_CPU_SH3
378 year
= tm
->tm_year
% 100;
379 writeb(BIN2BCD(year
), rtc
->regbase
+ RYRCNT
);
381 year
= (BIN2BCD((tm
->tm_year
+ 1900) / 100) << 8) |
382 BIN2BCD(tm
->tm_year
% 100);
383 writew(year
, rtc
->regbase
+ RYRCNT
);
387 tmp
= readb(rtc
->regbase
+ RCR2
);
389 tmp
|= RCR2_RTCEN
| RCR2_START
;
390 writeb(tmp
, rtc
->regbase
+ RCR2
);
392 spin_unlock_irq(&rtc
->lock
);
397 static inline int sh_rtc_read_alarm_value(struct sh_rtc
*rtc
, int reg_off
)
400 int value
= 0xff; /* return 0xff for ignored values */
402 byte
= readb(rtc
->regbase
+ reg_off
);
404 byte
&= ~AR_ENB
; /* strip the enable bit */
405 value
= BCD2BIN(byte
);
411 static int sh_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*wkalrm
)
413 struct platform_device
*pdev
= to_platform_device(dev
);
414 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
415 struct rtc_time
* tm
= &wkalrm
->time
;
417 spin_lock_irq(&rtc
->lock
);
419 tm
->tm_sec
= sh_rtc_read_alarm_value(rtc
, RSECAR
);
420 tm
->tm_min
= sh_rtc_read_alarm_value(rtc
, RMINAR
);
421 tm
->tm_hour
= sh_rtc_read_alarm_value(rtc
, RHRAR
);
422 tm
->tm_wday
= sh_rtc_read_alarm_value(rtc
, RWKAR
);
423 tm
->tm_mday
= sh_rtc_read_alarm_value(rtc
, RDAYAR
);
424 tm
->tm_mon
= sh_rtc_read_alarm_value(rtc
, RMONAR
);
426 tm
->tm_mon
-= 1; /* RTC is 1-12, tm_mon is 0-11 */
427 tm
->tm_year
= 0xffff;
429 wkalrm
->enabled
= (readb(rtc
->regbase
+ RCR1
) & RCR1_AIE
) ? 1 : 0;
431 spin_unlock_irq(&rtc
->lock
);
436 static inline void sh_rtc_write_alarm_value(struct sh_rtc
*rtc
,
437 int value
, int reg_off
)
439 /* < 0 for a value that is ignored */
441 writeb(0, rtc
->regbase
+ reg_off
);
443 writeb(BIN2BCD(value
) | AR_ENB
, rtc
->regbase
+ reg_off
);
446 static int sh_rtc_check_alarm(struct rtc_time
* tm
)
449 * The original rtc says anything > 0xc0 is "don't care" or "match
450 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
451 * The original rtc doesn't support years - some things use -1 and
452 * some 0xffff. We use -1 to make out tests easier.
454 if (tm
->tm_year
== 0xffff)
456 if (tm
->tm_mon
>= 0xff)
458 if (tm
->tm_mday
>= 0xff)
460 if (tm
->tm_wday
>= 0xff)
462 if (tm
->tm_hour
>= 0xff)
464 if (tm
->tm_min
>= 0xff)
466 if (tm
->tm_sec
>= 0xff)
469 if (tm
->tm_year
> 9999 ||
471 tm
->tm_mday
== 0 || tm
->tm_mday
>= 32 ||
481 static int sh_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*wkalrm
)
483 struct platform_device
*pdev
= to_platform_device(dev
);
484 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
486 struct rtc_time
*tm
= &wkalrm
->time
;
489 err
= sh_rtc_check_alarm(tm
);
490 if (unlikely(err
< 0))
493 spin_lock_irq(&rtc
->lock
);
495 /* disable alarm interrupt and clear the alarm flag */
496 rcr1
= readb(rtc
->regbase
+ RCR1
);
497 rcr1
&= ~(RCR1_AF
|RCR1_AIE
);
498 writeb(rcr1
, rtc
->regbase
+ RCR1
);
503 sh_rtc_write_alarm_value(rtc
, tm
->tm_sec
, RSECAR
);
504 sh_rtc_write_alarm_value(rtc
, tm
->tm_min
, RMINAR
);
505 sh_rtc_write_alarm_value(rtc
, tm
->tm_hour
, RHRAR
);
506 sh_rtc_write_alarm_value(rtc
, tm
->tm_wday
, RWKAR
);
507 sh_rtc_write_alarm_value(rtc
, tm
->tm_mday
, RDAYAR
);
511 sh_rtc_write_alarm_value(rtc
, mon
, RMONAR
);
513 if (wkalrm
->enabled
) {
515 writeb(rcr1
, rtc
->regbase
+ RCR1
);
518 spin_unlock_irq(&rtc
->lock
);
523 static struct rtc_class_ops sh_rtc_ops
= {
525 .release
= sh_rtc_release
,
526 .ioctl
= sh_rtc_ioctl
,
527 .read_time
= sh_rtc_read_time
,
528 .set_time
= sh_rtc_set_time
,
529 .read_alarm
= sh_rtc_read_alarm
,
530 .set_alarm
= sh_rtc_set_alarm
,
534 static int __devinit
sh_rtc_probe(struct platform_device
*pdev
)
537 struct resource
*res
;
540 rtc
= kzalloc(sizeof(struct sh_rtc
), GFP_KERNEL
);
544 spin_lock_init(&rtc
->lock
);
546 rtc
->periodic_irq
= platform_get_irq(pdev
, 0);
547 if (unlikely(rtc
->periodic_irq
< 0)) {
548 dev_err(&pdev
->dev
, "No IRQ for period\n");
552 rtc
->carry_irq
= platform_get_irq(pdev
, 1);
553 if (unlikely(rtc
->carry_irq
< 0)) {
554 dev_err(&pdev
->dev
, "No IRQ for carry\n");
558 rtc
->alarm_irq
= platform_get_irq(pdev
, 2);
559 if (unlikely(rtc
->alarm_irq
< 0)) {
560 dev_err(&pdev
->dev
, "No IRQ for alarm\n");
564 res
= platform_get_resource(pdev
, IORESOURCE_IO
, 0);
565 if (unlikely(res
== NULL
)) {
566 dev_err(&pdev
->dev
, "No IO resource\n");
570 rtc
->regsize
= res
->end
- res
->start
+ 1;
572 rtc
->res
= request_mem_region(res
->start
, rtc
->regsize
, pdev
->name
);
573 if (unlikely(!rtc
->res
)) {
578 rtc
->regbase
= (void __iomem
*)rtc
->res
->start
;
579 if (unlikely(!rtc
->regbase
)) {
584 rtc
->rtc_dev
= rtc_device_register("sh", &pdev
->dev
,
585 &sh_rtc_ops
, THIS_MODULE
);
587 ret
= PTR_ERR(rtc
->rtc_dev
);
591 platform_set_drvdata(pdev
, rtc
);
596 release_resource(rtc
->res
);
603 static int __devexit
sh_rtc_remove(struct platform_device
*pdev
)
605 struct sh_rtc
*rtc
= platform_get_drvdata(pdev
);
607 if (likely(rtc
->rtc_dev
))
608 rtc_device_unregister(rtc
->rtc_dev
);
610 sh_rtc_setpie(&pdev
->dev
, 0);
611 sh_rtc_setaie(&pdev
->dev
, 0);
613 release_resource(rtc
->res
);
615 platform_set_drvdata(pdev
, NULL
);
621 static struct platform_driver sh_rtc_platform_driver
= {
624 .owner
= THIS_MODULE
,
626 .probe
= sh_rtc_probe
,
627 .remove
= __devexit_p(sh_rtc_remove
),
630 static int __init
sh_rtc_init(void)
632 return platform_driver_register(&sh_rtc_platform_driver
);
635 static void __exit
sh_rtc_exit(void)
637 platform_driver_unregister(&sh_rtc_platform_driver
);
640 module_init(sh_rtc_init
);
641 module_exit(sh_rtc_exit
);
643 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
644 MODULE_VERSION(DRV_VERSION
);
645 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
646 MODULE_LICENSE("GPL");