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");
360 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
362 struct platform_device *pdev = to_platform_device(dev);
363 struct sh_rtc *rtc = platform_get_drvdata(pdev);
367 spin_lock_irq(&rtc->lock);
369 /* Reset pre-scaler & stop RTC */
370 tmp = readb(rtc->regbase + RCR2);
373 writeb(tmp, rtc->regbase + RCR2);
375 writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT);
376 writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT);
377 writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
378 writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
379 writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
380 writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT);
382 if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
383 year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
384 BIN2BCD(tm->tm_year % 100);
385 writew(year, rtc->regbase + RYRCNT);
387 year = tm->tm_year % 100;
388 writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
392 tmp = readb(rtc->regbase + RCR2);
394 tmp |= RCR2_RTCEN | RCR2_START;
395 writeb(tmp, rtc->regbase + RCR2);
397 spin_unlock_irq(&rtc->lock);
402 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
405 int value = 0xff; /* return 0xff for ignored values */
407 byte = readb(rtc->regbase + reg_off);
409 byte &= ~AR_ENB; /* strip the enable bit */
410 value = BCD2BIN(byte);
416 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
418 struct platform_device *pdev = to_platform_device(dev);
419 struct sh_rtc *rtc = platform_get_drvdata(pdev);
420 struct rtc_time* tm = &wkalrm->time;
422 spin_lock_irq(&rtc->lock);
424 tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR);
425 tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR);
426 tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR);
427 tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR);
428 tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR);
429 tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR);
431 tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
432 tm->tm_year = 0xffff;
434 wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
436 spin_unlock_irq(&rtc->lock);
441 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
442 int value, int reg_off)
444 /* < 0 for a value that is ignored */
446 writeb(0, rtc->regbase + reg_off);
448 writeb(BIN2BCD(value) | AR_ENB, rtc->regbase + reg_off);
451 static int sh_rtc_check_alarm(struct rtc_time* tm)
454 * The original rtc says anything > 0xc0 is "don't care" or "match
455 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
456 * The original rtc doesn't support years - some things use -1 and
457 * some 0xffff. We use -1 to make out tests easier.
459 if (tm->tm_year == 0xffff)
461 if (tm->tm_mon >= 0xff)
463 if (tm->tm_mday >= 0xff)
465 if (tm->tm_wday >= 0xff)
467 if (tm->tm_hour >= 0xff)
469 if (tm->tm_min >= 0xff)
471 if (tm->tm_sec >= 0xff)
474 if (tm->tm_year > 9999 ||
476 tm->tm_mday == 0 || tm->tm_mday >= 32 ||
486 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
488 struct platform_device *pdev = to_platform_device(dev);
489 struct sh_rtc *rtc = platform_get_drvdata(pdev);
491 struct rtc_time *tm = &wkalrm->time;
494 err = sh_rtc_check_alarm(tm);
495 if (unlikely(err < 0))
498 spin_lock_irq(&rtc->lock);
500 /* disable alarm interrupt and clear the alarm flag */
501 rcr1 = readb(rtc->regbase + RCR1);
502 rcr1 &= ~(RCR1_AF|RCR1_AIE);
503 writeb(rcr1, rtc->regbase + RCR1);
508 sh_rtc_write_alarm_value(rtc, tm->tm_sec, RSECAR);
509 sh_rtc_write_alarm_value(rtc, tm->tm_min, RMINAR);
510 sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
511 sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
512 sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
516 sh_rtc_write_alarm_value(rtc, mon, RMONAR);
518 if (wkalrm->enabled) {
520 writeb(rcr1, rtc->regbase + RCR1);
523 spin_unlock_irq(&rtc->lock);
528 static struct rtc_class_ops sh_rtc_ops = {
530 .release = sh_rtc_release,
531 .ioctl = sh_rtc_ioctl,
532 .read_time = sh_rtc_read_time,
533 .set_time = sh_rtc_set_time,
534 .read_alarm = sh_rtc_read_alarm,
535 .set_alarm = sh_rtc_set_alarm,
539 static int __devinit sh_rtc_probe(struct platform_device *pdev)
542 struct resource *res;
545 rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
549 spin_lock_init(&rtc->lock);
551 rtc->periodic_irq = platform_get_irq(pdev, 0);
552 if (unlikely(rtc->periodic_irq < 0)) {
553 dev_err(&pdev->dev, "No IRQ for period\n");
557 rtc->carry_irq = platform_get_irq(pdev, 1);
558 if (unlikely(rtc->carry_irq < 0)) {
559 dev_err(&pdev->dev, "No IRQ for carry\n");
563 rtc->alarm_irq = platform_get_irq(pdev, 2);
564 if (unlikely(rtc->alarm_irq < 0)) {
565 dev_err(&pdev->dev, "No IRQ for alarm\n");
569 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
570 if (unlikely(res == NULL)) {
571 dev_err(&pdev->dev, "No IO resource\n");
575 rtc->regsize = res->end - res->start + 1;
577 rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
578 if (unlikely(!rtc->res)) {
583 rtc->regbase = (void __iomem *)rtc->res->start;
584 if (unlikely(!rtc->regbase)) {
589 rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
590 &sh_rtc_ops, THIS_MODULE);
592 ret = PTR_ERR(rtc->rtc_dev);
596 rtc->capabilities = RTC_DEF_CAPABILITIES;
597 if (pdev->dev.platform_data) {
598 struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
601 * Some CPUs have special capabilities in addition to the
602 * default set. Add those in here.
604 rtc->capabilities |= pinfo->capabilities;
607 platform_set_drvdata(pdev, rtc);
612 release_resource(rtc->res);
619 static int __devexit sh_rtc_remove(struct platform_device *pdev)
621 struct sh_rtc *rtc = platform_get_drvdata(pdev);
623 if (likely(rtc->rtc_dev))
624 rtc_device_unregister(rtc->rtc_dev);
626 sh_rtc_setpie(&pdev->dev, 0);
627 sh_rtc_setaie(&pdev->dev, 0);
629 release_resource(rtc->res);
631 platform_set_drvdata(pdev, NULL);
637 static struct platform_driver sh_rtc_platform_driver = {
640 .owner = THIS_MODULE,
642 .probe = sh_rtc_probe,
643 .remove = __devexit_p(sh_rtc_remove),
646 static int __init sh_rtc_init(void)
648 return platform_driver_register(&sh_rtc_platform_driver);
651 static void __exit sh_rtc_exit(void)
653 platform_driver_unregister(&sh_rtc_platform_driver);
656 module_init(sh_rtc_init);
657 module_exit(sh_rtc_exit);
659 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
660 MODULE_VERSION(DRV_VERSION);
661 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
662 MODULE_LICENSE("GPL");