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 "0.1.4"
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
39 #elif defined(CONFIG_CPU_SH5)
40 #define rtc_reg_size sizeof(u32)
41 #define RTC_BIT_INVERTED 0 /* The SH-5 RTC is surprisingly sane! */
42 #define RTC_DEF_CAPABILITIES RTC_CAP_4_DIGIT_YEAR
45 #define RTC_REG(r) ((r) * rtc_reg_size)
47 #define R64CNT RTC_REG(0)
49 #define RSECCNT RTC_REG(1) /* RTC sec */
50 #define RMINCNT RTC_REG(2) /* RTC min */
51 #define RHRCNT RTC_REG(3) /* RTC hour */
52 #define RWKCNT RTC_REG(4) /* RTC week */
53 #define RDAYCNT RTC_REG(5) /* RTC day */
54 #define RMONCNT RTC_REG(6) /* RTC month */
55 #define RYRCNT RTC_REG(7) /* RTC year */
56 #define RSECAR RTC_REG(8) /* ALARM sec */
57 #define RMINAR RTC_REG(9) /* ALARM min */
58 #define RHRAR RTC_REG(10) /* ALARM hour */
59 #define RWKAR RTC_REG(11) /* ALARM week */
60 #define RDAYAR RTC_REG(12) /* ALARM day */
61 #define RMONAR RTC_REG(13) /* ALARM month */
62 #define RCR1 RTC_REG(14) /* Control */
63 #define RCR2 RTC_REG(15) /* Control */
65 /* ALARM Bits - or with BCD encoded value */
66 #define AR_ENB 0x80 /* Enable for alarm cmp */
69 #define RCR1_CF 0x80 /* Carry Flag */
70 #define RCR1_CIE 0x10 /* Carry Interrupt Enable */
71 #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
72 #define RCR1_AF 0x01 /* Alarm Flag */
75 #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
76 #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
77 #define RCR2_RTCEN 0x08 /* ENable RTC */
78 #define RCR2_ADJ 0x04 /* ADJustment (30-second) */
79 #define RCR2_RESET 0x02 /* Reset bit */
80 #define RCR2_START 0x01 /* Start bit */
83 void __iomem *regbase;
84 unsigned long regsize;
86 unsigned int alarm_irq, periodic_irq, carry_irq;
87 struct rtc_device *rtc_dev;
90 unsigned long capabilities; /* See asm-sh/rtc.h for cap bits */
93 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
95 struct platform_device *pdev = to_platform_device(dev_id);
96 struct sh_rtc *rtc = platform_get_drvdata(pdev);
97 unsigned int tmp, events = 0;
99 spin_lock(&rtc->lock);
101 tmp = readb(rtc->regbase + RCR1);
104 if (rtc->rearm_aie) {
106 tmp &= ~RCR1_AF; /* try to clear AF again */
108 tmp |= RCR1_AIE; /* AF has cleared, rearm IRQ */
113 writeb(tmp, rtc->regbase + RCR1);
115 rtc_update_irq(rtc->rtc_dev, 1, events);
117 spin_unlock(&rtc->lock);
122 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
124 struct platform_device *pdev = to_platform_device(dev_id);
125 struct sh_rtc *rtc = platform_get_drvdata(pdev);
126 unsigned int tmp, events = 0;
128 spin_lock(&rtc->lock);
130 tmp = readb(rtc->regbase + RCR1);
133 * If AF is set then the alarm has triggered. If we clear AF while
134 * the alarm time still matches the RTC time then AF will
135 * immediately be set again, and if AIE is enabled then the alarm
136 * interrupt will immediately be retrigger. So we clear AIE here
137 * and use rtc->rearm_aie so that the carry interrupt will keep
138 * trying to clear AF and once it stays cleared it'll re-enable
142 events |= RTC_AF | RTC_IRQF;
144 tmp &= ~(RCR1_AF|RCR1_AIE);
146 writeb(tmp, rtc->regbase + RCR1);
150 rtc_update_irq(rtc->rtc_dev, 1, events);
153 spin_unlock(&rtc->lock);
157 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
159 struct platform_device *pdev = to_platform_device(dev_id);
160 struct sh_rtc *rtc = platform_get_drvdata(pdev);
162 spin_lock(&rtc->lock);
164 rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
166 spin_unlock(&rtc->lock);
171 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
173 struct sh_rtc *rtc = dev_get_drvdata(dev);
176 spin_lock_irq(&rtc->lock);
178 tmp = readb(rtc->regbase + RCR2);
181 tmp &= ~RCR2_PESMASK;
182 tmp |= RCR2_PEF | (2 << 4);
184 tmp &= ~(RCR2_PESMASK | RCR2_PEF);
186 writeb(tmp, rtc->regbase + RCR2);
188 spin_unlock_irq(&rtc->lock);
191 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
193 struct sh_rtc *rtc = dev_get_drvdata(dev);
196 spin_lock_irq(&rtc->lock);
198 tmp = readb(rtc->regbase + RCR1);
203 } else if (rtc->rearm_aie == 0)
206 writeb(tmp, rtc->regbase + RCR1);
208 spin_unlock_irq(&rtc->lock);
211 static int sh_rtc_open(struct device *dev)
213 struct sh_rtc *rtc = dev_get_drvdata(dev);
217 tmp = readb(rtc->regbase + RCR1);
220 writeb(tmp, rtc->regbase + RCR1);
222 ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED,
223 "sh-rtc period", dev);
225 dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
226 ret, rtc->periodic_irq);
230 ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED,
231 "sh-rtc carry", dev);
233 dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
234 ret, rtc->carry_irq);
235 free_irq(rtc->periodic_irq, dev);
239 ret = request_irq(rtc->alarm_irq, sh_rtc_alarm, IRQF_DISABLED,
240 "sh-rtc alarm", dev);
242 dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
243 ret, rtc->alarm_irq);
250 free_irq(rtc->carry_irq, dev);
252 free_irq(rtc->periodic_irq, dev);
257 static void sh_rtc_release(struct device *dev)
259 struct sh_rtc *rtc = dev_get_drvdata(dev);
261 sh_rtc_setpie(dev, 0);
262 sh_rtc_setaie(dev, 0);
264 free_irq(rtc->periodic_irq, dev);
265 free_irq(rtc->carry_irq, dev);
266 free_irq(rtc->alarm_irq, dev);
269 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
271 struct sh_rtc *rtc = dev_get_drvdata(dev);
274 tmp = readb(rtc->regbase + RCR1);
275 seq_printf(seq, "carry_IRQ\t: %s\n",
276 (tmp & RCR1_CIE) ? "yes" : "no");
278 tmp = readb(rtc->regbase + RCR2);
279 seq_printf(seq, "periodic_IRQ\t: %s\n",
280 (tmp & RCR2_PEF) ? "yes" : "no");
285 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
287 unsigned int ret = -ENOIOCTLCMD;
292 sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
297 sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
305 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
307 struct platform_device *pdev = to_platform_device(dev);
308 struct sh_rtc *rtc = platform_get_drvdata(pdev);
309 unsigned int sec128, sec2, yr, yr100, cf_bit;
314 spin_lock_irq(&rtc->lock);
316 tmp = readb(rtc->regbase + RCR1);
317 tmp &= ~RCR1_CF; /* Clear CF-bit */
319 writeb(tmp, rtc->regbase + RCR1);
321 sec128 = readb(rtc->regbase + R64CNT);
323 tm->tm_sec = BCD2BIN(readb(rtc->regbase + RSECCNT));
324 tm->tm_min = BCD2BIN(readb(rtc->regbase + RMINCNT));
325 tm->tm_hour = BCD2BIN(readb(rtc->regbase + RHRCNT));
326 tm->tm_wday = BCD2BIN(readb(rtc->regbase + RWKCNT));
327 tm->tm_mday = BCD2BIN(readb(rtc->regbase + RDAYCNT));
328 tm->tm_mon = BCD2BIN(readb(rtc->regbase + RMONCNT)) - 1;
330 if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
331 yr = readw(rtc->regbase + RYRCNT);
332 yr100 = BCD2BIN(yr >> 8);
335 yr = readb(rtc->regbase + RYRCNT);
336 yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
339 tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
341 sec2 = readb(rtc->regbase + R64CNT);
342 cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
344 spin_unlock_irq(&rtc->lock);
345 } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
347 #if RTC_BIT_INVERTED != 0
348 if ((sec128 & RTC_BIT_INVERTED))
352 dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
353 "mday=%d, mon=%d, year=%d, wday=%d\n",
355 tm->tm_sec, tm->tm_min, tm->tm_hour,
356 tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
358 if (rtc_valid_tm(tm) < 0) {
359 dev_err(dev, "invalid date\n");
360 rtc_time_to_tm(0, tm);
366 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
368 struct platform_device *pdev = to_platform_device(dev);
369 struct sh_rtc *rtc = platform_get_drvdata(pdev);
373 spin_lock_irq(&rtc->lock);
375 /* Reset pre-scaler & stop RTC */
376 tmp = readb(rtc->regbase + RCR2);
379 writeb(tmp, rtc->regbase + RCR2);
381 writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT);
382 writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT);
383 writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
384 writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
385 writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
386 writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT);
388 if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
389 year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
390 BIN2BCD(tm->tm_year % 100);
391 writew(year, rtc->regbase + RYRCNT);
393 year = tm->tm_year % 100;
394 writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
398 tmp = readb(rtc->regbase + RCR2);
400 tmp |= RCR2_RTCEN | RCR2_START;
401 writeb(tmp, rtc->regbase + RCR2);
403 spin_unlock_irq(&rtc->lock);
408 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
411 int value = 0xff; /* return 0xff for ignored values */
413 byte = readb(rtc->regbase + reg_off);
415 byte &= ~AR_ENB; /* strip the enable bit */
416 value = BCD2BIN(byte);
422 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
424 struct platform_device *pdev = to_platform_device(dev);
425 struct sh_rtc *rtc = platform_get_drvdata(pdev);
426 struct rtc_time* tm = &wkalrm->time;
428 spin_lock_irq(&rtc->lock);
430 tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR);
431 tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR);
432 tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR);
433 tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR);
434 tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR);
435 tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR);
437 tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
438 tm->tm_year = 0xffff;
440 wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
442 spin_unlock_irq(&rtc->lock);
447 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
448 int value, int reg_off)
450 /* < 0 for a value that is ignored */
452 writeb(0, rtc->regbase + reg_off);
454 writeb(BIN2BCD(value) | AR_ENB, rtc->regbase + reg_off);
457 static int sh_rtc_check_alarm(struct rtc_time* tm)
460 * The original rtc says anything > 0xc0 is "don't care" or "match
461 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
462 * The original rtc doesn't support years - some things use -1 and
463 * some 0xffff. We use -1 to make out tests easier.
465 if (tm->tm_year == 0xffff)
467 if (tm->tm_mon >= 0xff)
469 if (tm->tm_mday >= 0xff)
471 if (tm->tm_wday >= 0xff)
473 if (tm->tm_hour >= 0xff)
475 if (tm->tm_min >= 0xff)
477 if (tm->tm_sec >= 0xff)
480 if (tm->tm_year > 9999 ||
482 tm->tm_mday == 0 || tm->tm_mday >= 32 ||
492 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
494 struct platform_device *pdev = to_platform_device(dev);
495 struct sh_rtc *rtc = platform_get_drvdata(pdev);
497 struct rtc_time *tm = &wkalrm->time;
500 err = sh_rtc_check_alarm(tm);
501 if (unlikely(err < 0))
504 spin_lock_irq(&rtc->lock);
506 /* disable alarm interrupt and clear the alarm flag */
507 rcr1 = readb(rtc->regbase + RCR1);
508 rcr1 &= ~(RCR1_AF|RCR1_AIE);
509 writeb(rcr1, rtc->regbase + RCR1);
514 sh_rtc_write_alarm_value(rtc, tm->tm_sec, RSECAR);
515 sh_rtc_write_alarm_value(rtc, tm->tm_min, RMINAR);
516 sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
517 sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
518 sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
522 sh_rtc_write_alarm_value(rtc, mon, RMONAR);
524 if (wkalrm->enabled) {
526 writeb(rcr1, rtc->regbase + RCR1);
529 spin_unlock_irq(&rtc->lock);
534 static struct rtc_class_ops sh_rtc_ops = {
536 .release = sh_rtc_release,
537 .ioctl = sh_rtc_ioctl,
538 .read_time = sh_rtc_read_time,
539 .set_time = sh_rtc_set_time,
540 .read_alarm = sh_rtc_read_alarm,
541 .set_alarm = sh_rtc_set_alarm,
545 static int __devinit sh_rtc_probe(struct platform_device *pdev)
548 struct resource *res;
551 rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
555 spin_lock_init(&rtc->lock);
557 rtc->periodic_irq = platform_get_irq(pdev, 0);
558 if (unlikely(rtc->periodic_irq < 0)) {
559 dev_err(&pdev->dev, "No IRQ for period\n");
563 rtc->carry_irq = platform_get_irq(pdev, 1);
564 if (unlikely(rtc->carry_irq < 0)) {
565 dev_err(&pdev->dev, "No IRQ for carry\n");
569 rtc->alarm_irq = platform_get_irq(pdev, 2);
570 if (unlikely(rtc->alarm_irq < 0)) {
571 dev_err(&pdev->dev, "No IRQ for alarm\n");
575 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
576 if (unlikely(res == NULL)) {
577 dev_err(&pdev->dev, "No IO resource\n");
581 rtc->regsize = res->end - res->start + 1;
583 rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
584 if (unlikely(!rtc->res)) {
589 rtc->regbase = (void __iomem *)rtc->res->start;
590 if (unlikely(!rtc->regbase)) {
595 rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
596 &sh_rtc_ops, THIS_MODULE);
597 if (IS_ERR(rtc->rtc_dev)) {
598 ret = PTR_ERR(rtc->rtc_dev);
602 rtc->capabilities = RTC_DEF_CAPABILITIES;
603 if (pdev->dev.platform_data) {
604 struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
607 * Some CPUs have special capabilities in addition to the
608 * default set. Add those in here.
610 rtc->capabilities |= pinfo->capabilities;
613 platform_set_drvdata(pdev, rtc);
618 release_resource(rtc->res);
625 static int __devexit sh_rtc_remove(struct platform_device *pdev)
627 struct sh_rtc *rtc = platform_get_drvdata(pdev);
629 if (likely(rtc->rtc_dev))
630 rtc_device_unregister(rtc->rtc_dev);
632 sh_rtc_setpie(&pdev->dev, 0);
633 sh_rtc_setaie(&pdev->dev, 0);
635 release_resource(rtc->res);
637 platform_set_drvdata(pdev, NULL);
643 static struct platform_driver sh_rtc_platform_driver = {
646 .owner = THIS_MODULE,
648 .probe = sh_rtc_probe,
649 .remove = __devexit_p(sh_rtc_remove),
652 static int __init sh_rtc_init(void)
654 return platform_driver_register(&sh_rtc_platform_driver);
657 static void __exit sh_rtc_exit(void)
659 platform_driver_unregister(&sh_rtc_platform_driver);
662 module_init(sh_rtc_init);
663 module_exit(sh_rtc_exit);
665 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
666 MODULE_VERSION(DRV_VERSION);
667 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
668 MODULE_LICENSE("GPL");