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->class_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->class_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->class_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, "alarm_IRQ\t: %s\n",
268 (tmp & RCR1_AIE) ? "yes" : "no");
269 seq_printf(seq, "carry_IRQ\t: %s\n",
270 (tmp & RCR1_CIE) ? "yes" : "no");
272 tmp = readb(rtc->regbase + RCR2);
273 seq_printf(seq, "periodic_IRQ\t: %s\n",
274 (tmp & RCR2_PEF) ? "yes" : "no");
279 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
281 unsigned int ret = -ENOIOCTLCMD;
286 sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
291 sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
299 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
301 struct platform_device *pdev = to_platform_device(dev);
302 struct sh_rtc *rtc = platform_get_drvdata(pdev);
303 unsigned int sec128, sec2, yr, yr100, cf_bit;
308 spin_lock_irq(&rtc->lock);
310 tmp = readb(rtc->regbase + RCR1);
311 tmp &= ~RCR1_CF; /* Clear CF-bit */
313 writeb(tmp, rtc->regbase + RCR1);
315 sec128 = readb(rtc->regbase + R64CNT);
317 tm->tm_sec = BCD2BIN(readb(rtc->regbase + RSECCNT));
318 tm->tm_min = BCD2BIN(readb(rtc->regbase + RMINCNT));
319 tm->tm_hour = BCD2BIN(readb(rtc->regbase + RHRCNT));
320 tm->tm_wday = BCD2BIN(readb(rtc->regbase + RWKCNT));
321 tm->tm_mday = BCD2BIN(readb(rtc->regbase + RDAYCNT));
322 tm->tm_mon = BCD2BIN(readb(rtc->regbase + RMONCNT)) - 1;
324 #if defined(CONFIG_CPU_SH4)
325 yr = readw(rtc->regbase + RYRCNT);
326 yr100 = BCD2BIN(yr >> 8);
329 yr = readb(rtc->regbase + RYRCNT);
330 yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
333 tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
335 sec2 = readb(rtc->regbase + R64CNT);
336 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
338 spin_unlock_irq(&rtc->lock);
339 } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
341 #if RTC_BIT_INVERTED != 0
342 if ((sec128 & RTC_BIT_INVERTED))
346 dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
347 "mday=%d, mon=%d, year=%d, wday=%d\n",
349 tm->tm_sec, tm->tm_min, tm->tm_hour,
350 tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
352 if (rtc_valid_tm(tm) < 0)
353 dev_err(dev, "invalid date\n");
358 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
360 struct platform_device *pdev = to_platform_device(dev);
361 struct sh_rtc *rtc = platform_get_drvdata(pdev);
365 spin_lock_irq(&rtc->lock);
367 /* Reset pre-scaler & stop RTC */
368 tmp = readb(rtc->regbase + RCR2);
370 writeb(tmp, rtc->regbase + RCR2);
372 writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT);
373 writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT);
374 writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
375 writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
376 writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
377 writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT);
379 #ifdef CONFIG_CPU_SH3
380 year = tm->tm_year % 100;
381 writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
383 year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
384 BIN2BCD(tm->tm_year % 100);
385 writew(year, rtc->regbase + RYRCNT);
389 tmp = readb(rtc->regbase + RCR2);
391 tmp |= RCR2_RTCEN | RCR2_START;
392 writeb(tmp, rtc->regbase + RCR2);
394 spin_unlock_irq(&rtc->lock);
399 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
402 int value = 0xff; /* return 0xff for ignored values */
404 byte = readb(rtc->regbase + reg_off);
406 byte &= ~AR_ENB; /* strip the enable bit */
407 value = BCD2BIN(byte);
413 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
415 struct platform_device *pdev = to_platform_device(dev);
416 struct sh_rtc *rtc = platform_get_drvdata(pdev);
417 struct rtc_time* tm = &wkalrm->time;
419 spin_lock_irq(&rtc->lock);
421 tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR);
422 tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR);
423 tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR);
424 tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR);
425 tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR);
426 tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR);
428 tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
429 tm->tm_year = 0xffff;
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 flag */
496 rcr1 = readb(rtc->regbase + RCR1);
498 writeb(rcr1 & ~RCR1_AIE, 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 /* Restore interrupt activation status */
514 writeb(rcr1, rtc->regbase + RCR1);
516 spin_unlock_irq(&rtc->lock);
521 static struct rtc_class_ops sh_rtc_ops = {
523 .release = sh_rtc_release,
524 .ioctl = sh_rtc_ioctl,
525 .read_time = sh_rtc_read_time,
526 .set_time = sh_rtc_set_time,
527 .read_alarm = sh_rtc_read_alarm,
528 .set_alarm = sh_rtc_set_alarm,
532 static int __devinit sh_rtc_probe(struct platform_device *pdev)
535 struct resource *res;
538 rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
542 spin_lock_init(&rtc->lock);
544 rtc->periodic_irq = platform_get_irq(pdev, 0);
545 if (unlikely(rtc->periodic_irq < 0)) {
546 dev_err(&pdev->dev, "No IRQ for period\n");
550 rtc->carry_irq = platform_get_irq(pdev, 1);
551 if (unlikely(rtc->carry_irq < 0)) {
552 dev_err(&pdev->dev, "No IRQ for carry\n");
556 rtc->alarm_irq = platform_get_irq(pdev, 2);
557 if (unlikely(rtc->alarm_irq < 0)) {
558 dev_err(&pdev->dev, "No IRQ for alarm\n");
562 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
563 if (unlikely(res == NULL)) {
564 dev_err(&pdev->dev, "No IO resource\n");
568 rtc->regsize = res->end - res->start + 1;
570 rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
571 if (unlikely(!rtc->res)) {
576 rtc->regbase = (void __iomem *)rtc->res->start;
577 if (unlikely(!rtc->regbase)) {
582 rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
583 &sh_rtc_ops, THIS_MODULE);
585 ret = PTR_ERR(rtc->rtc_dev);
589 platform_set_drvdata(pdev, rtc);
594 release_resource(rtc->res);
601 static int __devexit sh_rtc_remove(struct platform_device *pdev)
603 struct sh_rtc *rtc = platform_get_drvdata(pdev);
605 if (likely(rtc->rtc_dev))
606 rtc_device_unregister(rtc->rtc_dev);
608 sh_rtc_setpie(&pdev->dev, 0);
609 sh_rtc_setaie(&pdev->dev, 0);
611 release_resource(rtc->res);
613 platform_set_drvdata(pdev, NULL);
619 static struct platform_driver sh_rtc_platform_driver = {
622 .owner = THIS_MODULE,
624 .probe = sh_rtc_probe,
625 .remove = __devexit_p(sh_rtc_remove),
628 static int __init sh_rtc_init(void)
630 return platform_driver_register(&sh_rtc_platform_driver);
633 static void __exit sh_rtc_exit(void)
635 platform_driver_unregister(&sh_rtc_platform_driver);
638 module_init(sh_rtc_init);
639 module_exit(sh_rtc_exit);
641 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
642 MODULE_VERSION(DRV_VERSION);
643 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
644 MODULE_LICENSE("GPL");