xref: /linux/drivers/rtc/rtc-sh.c (revision 93fde774546c947ac8563da431f0a6d47452551d)
1 /*
2  * SuperH On-Chip RTC Support
3  *
4  * Copyright (C) 2006, 2007, 2008  Paul Mundt
5  * Copyright (C) 2006  Jamie Lenehan
6  * Copyright (C) 2008  Angelo Castello
7  *
8  * Based on the old arch/sh/kernel/cpu/rtc.c by:
9  *
10  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
11  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
12  *
13  * This file is subject to the terms and conditions of the GNU General Public
14  * License.  See the file "COPYING" in the main directory of this archive
15  * for more details.
16  */
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/bcd.h>
20 #include <linux/rtc.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/seq_file.h>
24 #include <linux/interrupt.h>
25 #include <linux/spinlock.h>
26 #include <linux/io.h>
27 #include <linux/log2.h>
28 #include <asm/rtc.h>
29 
30 #define DRV_NAME	"sh-rtc"
31 #define DRV_VERSION	"0.2.0"
32 
33 #define RTC_REG(r)	((r) * rtc_reg_size)
34 
35 #define R64CNT		RTC_REG(0)
36 
37 #define RSECCNT		RTC_REG(1)	/* RTC sec */
38 #define RMINCNT		RTC_REG(2)	/* RTC min */
39 #define RHRCNT		RTC_REG(3)	/* RTC hour */
40 #define RWKCNT		RTC_REG(4)	/* RTC week */
41 #define RDAYCNT		RTC_REG(5)	/* RTC day */
42 #define RMONCNT		RTC_REG(6)	/* RTC month */
43 #define RYRCNT		RTC_REG(7)	/* RTC year */
44 #define RSECAR		RTC_REG(8)	/* ALARM sec */
45 #define RMINAR		RTC_REG(9)	/* ALARM min */
46 #define RHRAR		RTC_REG(10)	/* ALARM hour */
47 #define RWKAR		RTC_REG(11)	/* ALARM week */
48 #define RDAYAR		RTC_REG(12)	/* ALARM day */
49 #define RMONAR		RTC_REG(13)	/* ALARM month */
50 #define RCR1		RTC_REG(14)	/* Control */
51 #define RCR2		RTC_REG(15)	/* Control */
52 
53 /*
54  * Note on RYRAR and RCR3: Up until this point most of the register
55  * definitions are consistent across all of the available parts. However,
56  * the placement of the optional RYRAR and RCR3 (the RYRAR control
57  * register used to control RYRCNT/RYRAR compare) varies considerably
58  * across various parts, occasionally being mapped in to a completely
59  * unrelated address space. For proper RYRAR support a separate resource
60  * would have to be handed off, but as this is purely optional in
61  * practice, we simply opt not to support it, thereby keeping the code
62  * quite a bit more simplified.
63  */
64 
65 /* ALARM Bits - or with BCD encoded value */
66 #define AR_ENB		0x80	/* Enable for alarm cmp   */
67 
68 /* Period Bits */
69 #define PF_HP		0x100	/* Enable Half Period to support 8,32,128Hz */
70 #define PF_COUNT	0x200	/* Half periodic counter */
71 #define PF_OXS		0x400	/* Periodic One x Second */
72 #define PF_KOU		0x800	/* Kernel or User periodic request 1=kernel */
73 #define PF_MASK		0xf00
74 
75 /* RCR1 Bits */
76 #define RCR1_CF		0x80	/* Carry Flag             */
77 #define RCR1_CIE	0x10	/* Carry Interrupt Enable */
78 #define RCR1_AIE	0x08	/* Alarm Interrupt Enable */
79 #define RCR1_AF		0x01	/* Alarm Flag             */
80 
81 /* RCR2 Bits */
82 #define RCR2_PEF	0x80	/* PEriodic interrupt Flag */
83 #define RCR2_PESMASK	0x70	/* Periodic interrupt Set  */
84 #define RCR2_RTCEN	0x08	/* ENable RTC              */
85 #define RCR2_ADJ	0x04	/* ADJustment (30-second)  */
86 #define RCR2_RESET	0x02	/* Reset bit               */
87 #define RCR2_START	0x01	/* Start bit               */
88 
89 struct sh_rtc {
90 	void __iomem *regbase;
91 	unsigned long regsize;
92 	struct resource *res;
93 	int alarm_irq;
94 	int periodic_irq;
95 	int carry_irq;
96 	struct rtc_device *rtc_dev;
97 	spinlock_t lock;
98 	unsigned long capabilities;	/* See asm-sh/rtc.h for cap bits */
99 	unsigned short periodic_freq;
100 };
101 
102 static int __sh_rtc_interrupt(struct sh_rtc *rtc)
103 {
104 	unsigned int tmp, pending;
105 
106 	tmp = readb(rtc->regbase + RCR1);
107 	pending = tmp & RCR1_CF;
108 	tmp &= ~RCR1_CF;
109 	writeb(tmp, rtc->regbase + RCR1);
110 
111 	/* Users have requested One x Second IRQ */
112 	if (pending && rtc->periodic_freq & PF_OXS)
113 		rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
114 
115 	return pending;
116 }
117 
118 static int __sh_rtc_alarm(struct sh_rtc *rtc)
119 {
120 	unsigned int tmp, pending;
121 
122 	tmp = readb(rtc->regbase + RCR1);
123 	pending = tmp & RCR1_AF;
124 	tmp &= ~(RCR1_AF | RCR1_AIE);
125 	writeb(tmp, rtc->regbase + RCR1);
126 
127 	if (pending)
128 		rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
129 
130 	return pending;
131 }
132 
133 static int __sh_rtc_periodic(struct sh_rtc *rtc)
134 {
135 	struct rtc_device *rtc_dev = rtc->rtc_dev;
136 	struct rtc_task *irq_task;
137 	unsigned int tmp, pending;
138 
139 	tmp = readb(rtc->regbase + RCR2);
140 	pending = tmp & RCR2_PEF;
141 	tmp &= ~RCR2_PEF;
142 	writeb(tmp, rtc->regbase + RCR2);
143 
144 	if (!pending)
145 		return 0;
146 
147 	/* Half period enabled than one skipped and the next notified */
148 	if ((rtc->periodic_freq & PF_HP) && (rtc->periodic_freq & PF_COUNT))
149 		rtc->periodic_freq &= ~PF_COUNT;
150 	else {
151 		if (rtc->periodic_freq & PF_HP)
152 			rtc->periodic_freq |= PF_COUNT;
153 		if (rtc->periodic_freq & PF_KOU) {
154 			spin_lock(&rtc_dev->irq_task_lock);
155 			irq_task = rtc_dev->irq_task;
156 			if (irq_task)
157 				irq_task->func(irq_task->private_data);
158 			spin_unlock(&rtc_dev->irq_task_lock);
159 		} else
160 			rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
161 	}
162 
163 	return pending;
164 }
165 
166 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
167 {
168 	struct sh_rtc *rtc = dev_id;
169 	int ret;
170 
171 	spin_lock(&rtc->lock);
172 	ret = __sh_rtc_interrupt(rtc);
173 	spin_unlock(&rtc->lock);
174 
175 	return IRQ_RETVAL(ret);
176 }
177 
178 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
179 {
180 	struct sh_rtc *rtc = dev_id;
181 	int ret;
182 
183 	spin_lock(&rtc->lock);
184 	ret = __sh_rtc_alarm(rtc);
185 	spin_unlock(&rtc->lock);
186 
187 	return IRQ_RETVAL(ret);
188 }
189 
190 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
191 {
192 	struct sh_rtc *rtc = dev_id;
193 	int ret;
194 
195 	spin_lock(&rtc->lock);
196 	ret = __sh_rtc_periodic(rtc);
197 	spin_unlock(&rtc->lock);
198 
199 	return IRQ_RETVAL(ret);
200 }
201 
202 static irqreturn_t sh_rtc_shared(int irq, void *dev_id)
203 {
204 	struct sh_rtc *rtc = dev_id;
205 	int ret;
206 
207 	spin_lock(&rtc->lock);
208 	ret = __sh_rtc_interrupt(rtc);
209 	ret |= __sh_rtc_alarm(rtc);
210 	ret |= __sh_rtc_periodic(rtc);
211 	spin_unlock(&rtc->lock);
212 
213 	return IRQ_RETVAL(ret);
214 }
215 
216 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
217 {
218 	struct sh_rtc *rtc = dev_get_drvdata(dev);
219 	unsigned int tmp;
220 
221 	spin_lock_irq(&rtc->lock);
222 
223 	tmp = readb(rtc->regbase + RCR2);
224 
225 	if (enable) {
226 		tmp &= ~RCR2_PEF;	/* Clear PES bit */
227 		tmp |= (rtc->periodic_freq & ~PF_HP);	/* Set PES2-0 */
228 	} else
229 		tmp &= ~(RCR2_PESMASK | RCR2_PEF);
230 
231 	writeb(tmp, rtc->regbase + RCR2);
232 
233 	spin_unlock_irq(&rtc->lock);
234 }
235 
236 static inline int sh_rtc_setfreq(struct device *dev, unsigned int freq)
237 {
238 	struct sh_rtc *rtc = dev_get_drvdata(dev);
239 	int tmp, ret = 0;
240 
241 	spin_lock_irq(&rtc->lock);
242 	tmp = rtc->periodic_freq & PF_MASK;
243 
244 	switch (freq) {
245 	case 0:
246 		rtc->periodic_freq = 0x00;
247 		break;
248 	case 1:
249 		rtc->periodic_freq = 0x60;
250 		break;
251 	case 2:
252 		rtc->periodic_freq = 0x50;
253 		break;
254 	case 4:
255 		rtc->periodic_freq = 0x40;
256 		break;
257 	case 8:
258 		rtc->periodic_freq = 0x30 | PF_HP;
259 		break;
260 	case 16:
261 		rtc->periodic_freq = 0x30;
262 		break;
263 	case 32:
264 		rtc->periodic_freq = 0x20 | PF_HP;
265 		break;
266 	case 64:
267 		rtc->periodic_freq = 0x20;
268 		break;
269 	case 128:
270 		rtc->periodic_freq = 0x10 | PF_HP;
271 		break;
272 	case 256:
273 		rtc->periodic_freq = 0x10;
274 		break;
275 	default:
276 		ret = -ENOTSUPP;
277 	}
278 
279 	if (ret == 0) {
280 		rtc->periodic_freq |= tmp;
281 		rtc->rtc_dev->irq_freq = freq;
282 	}
283 
284 	spin_unlock_irq(&rtc->lock);
285 	return ret;
286 }
287 
288 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
289 {
290 	struct sh_rtc *rtc = dev_get_drvdata(dev);
291 	unsigned int tmp;
292 
293 	spin_lock_irq(&rtc->lock);
294 
295 	tmp = readb(rtc->regbase + RCR1);
296 
297 	if (!enable)
298 		tmp &= ~RCR1_AIE;
299 	else
300 		tmp |= RCR1_AIE;
301 
302 	writeb(tmp, rtc->regbase + RCR1);
303 
304 	spin_unlock_irq(&rtc->lock);
305 }
306 
307 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
308 {
309 	struct sh_rtc *rtc = dev_get_drvdata(dev);
310 	unsigned int tmp;
311 
312 	tmp = readb(rtc->regbase + RCR1);
313 	seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no");
314 
315 	tmp = readb(rtc->regbase + RCR2);
316 	seq_printf(seq, "periodic_IRQ\t: %s\n",
317 		   (tmp & RCR2_PESMASK) ? "yes" : "no");
318 
319 	return 0;
320 }
321 
322 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
323 {
324 	struct sh_rtc *rtc = dev_get_drvdata(dev);
325 	unsigned int ret = 0;
326 
327 	switch (cmd) {
328 	case RTC_PIE_OFF:
329 	case RTC_PIE_ON:
330 		sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
331 		break;
332 	case RTC_AIE_OFF:
333 	case RTC_AIE_ON:
334 		sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
335 		break;
336 	case RTC_UIE_OFF:
337 		rtc->periodic_freq &= ~PF_OXS;
338 		break;
339 	case RTC_UIE_ON:
340 		rtc->periodic_freq |= PF_OXS;
341 		break;
342 	case RTC_IRQP_READ:
343 		ret = put_user(rtc->rtc_dev->irq_freq,
344 			       (unsigned long __user *)arg);
345 		break;
346 	case RTC_IRQP_SET:
347 		ret = sh_rtc_setfreq(dev, arg);
348 		break;
349 	default:
350 		ret = -ENOIOCTLCMD;
351 	}
352 
353 	return ret;
354 }
355 
356 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
357 {
358 	struct platform_device *pdev = to_platform_device(dev);
359 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
360 	unsigned int sec128, sec2, yr, yr100, cf_bit;
361 
362 	do {
363 		unsigned int tmp;
364 
365 		spin_lock_irq(&rtc->lock);
366 
367 		tmp = readb(rtc->regbase + RCR1);
368 		tmp &= ~RCR1_CF; /* Clear CF-bit */
369 		tmp |= RCR1_CIE;
370 		writeb(tmp, rtc->regbase + RCR1);
371 
372 		sec128 = readb(rtc->regbase + R64CNT);
373 
374 		tm->tm_sec	= bcd2bin(readb(rtc->regbase + RSECCNT));
375 		tm->tm_min	= bcd2bin(readb(rtc->regbase + RMINCNT));
376 		tm->tm_hour	= bcd2bin(readb(rtc->regbase + RHRCNT));
377 		tm->tm_wday	= bcd2bin(readb(rtc->regbase + RWKCNT));
378 		tm->tm_mday	= bcd2bin(readb(rtc->regbase + RDAYCNT));
379 		tm->tm_mon	= bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
380 
381 		if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
382 			yr  = readw(rtc->regbase + RYRCNT);
383 			yr100 = bcd2bin(yr >> 8);
384 			yr &= 0xff;
385 		} else {
386 			yr  = readb(rtc->regbase + RYRCNT);
387 			yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
388 		}
389 
390 		tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
391 
392 		sec2 = readb(rtc->regbase + R64CNT);
393 		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
394 
395 		spin_unlock_irq(&rtc->lock);
396 	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
397 
398 #if RTC_BIT_INVERTED != 0
399 	if ((sec128 & RTC_BIT_INVERTED))
400 		tm->tm_sec--;
401 #endif
402 
403 	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
404 		"mday=%d, mon=%d, year=%d, wday=%d\n",
405 		__func__,
406 		tm->tm_sec, tm->tm_min, tm->tm_hour,
407 		tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
408 
409 	if (rtc_valid_tm(tm) < 0) {
410 		dev_err(dev, "invalid date\n");
411 		rtc_time_to_tm(0, tm);
412 	}
413 
414 	return 0;
415 }
416 
417 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
418 {
419 	struct platform_device *pdev = to_platform_device(dev);
420 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
421 	unsigned int tmp;
422 	int year;
423 
424 	spin_lock_irq(&rtc->lock);
425 
426 	/* Reset pre-scaler & stop RTC */
427 	tmp = readb(rtc->regbase + RCR2);
428 	tmp |= RCR2_RESET;
429 	tmp &= ~RCR2_START;
430 	writeb(tmp, rtc->regbase + RCR2);
431 
432 	writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
433 	writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
434 	writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
435 	writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
436 	writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
437 	writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
438 
439 	if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
440 		year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
441 			bin2bcd(tm->tm_year % 100);
442 		writew(year, rtc->regbase + RYRCNT);
443 	} else {
444 		year = tm->tm_year % 100;
445 		writeb(bin2bcd(year), rtc->regbase + RYRCNT);
446 	}
447 
448 	/* Start RTC */
449 	tmp = readb(rtc->regbase + RCR2);
450 	tmp &= ~RCR2_RESET;
451 	tmp |= RCR2_RTCEN | RCR2_START;
452 	writeb(tmp, rtc->regbase + RCR2);
453 
454 	spin_unlock_irq(&rtc->lock);
455 
456 	return 0;
457 }
458 
459 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
460 {
461 	unsigned int byte;
462 	int value = 0xff;	/* return 0xff for ignored values */
463 
464 	byte = readb(rtc->regbase + reg_off);
465 	if (byte & AR_ENB) {
466 		byte &= ~AR_ENB;	/* strip the enable bit */
467 		value = bcd2bin(byte);
468 	}
469 
470 	return value;
471 }
472 
473 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
474 {
475 	struct platform_device *pdev = to_platform_device(dev);
476 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
477 	struct rtc_time *tm = &wkalrm->time;
478 
479 	spin_lock_irq(&rtc->lock);
480 
481 	tm->tm_sec	= sh_rtc_read_alarm_value(rtc, RSECAR);
482 	tm->tm_min	= sh_rtc_read_alarm_value(rtc, RMINAR);
483 	tm->tm_hour	= sh_rtc_read_alarm_value(rtc, RHRAR);
484 	tm->tm_wday	= sh_rtc_read_alarm_value(rtc, RWKAR);
485 	tm->tm_mday	= sh_rtc_read_alarm_value(rtc, RDAYAR);
486 	tm->tm_mon	= sh_rtc_read_alarm_value(rtc, RMONAR);
487 	if (tm->tm_mon > 0)
488 		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
489 	tm->tm_year     = 0xffff;
490 
491 	wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
492 
493 	spin_unlock_irq(&rtc->lock);
494 
495 	return 0;
496 }
497 
498 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
499 					    int value, int reg_off)
500 {
501 	/* < 0 for a value that is ignored */
502 	if (value < 0)
503 		writeb(0, rtc->regbase + reg_off);
504 	else
505 		writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
506 }
507 
508 static int sh_rtc_check_alarm(struct rtc_time *tm)
509 {
510 	/*
511 	 * The original rtc says anything > 0xc0 is "don't care" or "match
512 	 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
513 	 * The original rtc doesn't support years - some things use -1 and
514 	 * some 0xffff. We use -1 to make out tests easier.
515 	 */
516 	if (tm->tm_year == 0xffff)
517 		tm->tm_year = -1;
518 	if (tm->tm_mon >= 0xff)
519 		tm->tm_mon = -1;
520 	if (tm->tm_mday >= 0xff)
521 		tm->tm_mday = -1;
522 	if (tm->tm_wday >= 0xff)
523 		tm->tm_wday = -1;
524 	if (tm->tm_hour >= 0xff)
525 		tm->tm_hour = -1;
526 	if (tm->tm_min >= 0xff)
527 		tm->tm_min = -1;
528 	if (tm->tm_sec >= 0xff)
529 		tm->tm_sec = -1;
530 
531 	if (tm->tm_year > 9999 ||
532 		tm->tm_mon >= 12 ||
533 		tm->tm_mday == 0 || tm->tm_mday >= 32 ||
534 		tm->tm_wday >= 7 ||
535 		tm->tm_hour >= 24 ||
536 		tm->tm_min >= 60 ||
537 		tm->tm_sec >= 60)
538 		return -EINVAL;
539 
540 	return 0;
541 }
542 
543 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
544 {
545 	struct platform_device *pdev = to_platform_device(dev);
546 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
547 	unsigned int rcr1;
548 	struct rtc_time *tm = &wkalrm->time;
549 	int mon, err;
550 
551 	err = sh_rtc_check_alarm(tm);
552 	if (unlikely(err < 0))
553 		return err;
554 
555 	spin_lock_irq(&rtc->lock);
556 
557 	/* disable alarm interrupt and clear the alarm flag */
558 	rcr1 = readb(rtc->regbase + RCR1);
559 	rcr1 &= ~(RCR1_AF | RCR1_AIE);
560 	writeb(rcr1, rtc->regbase + RCR1);
561 
562 	/* set alarm time */
563 	sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
564 	sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
565 	sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
566 	sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
567 	sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
568 	mon = tm->tm_mon;
569 	if (mon >= 0)
570 		mon += 1;
571 	sh_rtc_write_alarm_value(rtc, mon, RMONAR);
572 
573 	if (wkalrm->enabled) {
574 		rcr1 |= RCR1_AIE;
575 		writeb(rcr1, rtc->regbase + RCR1);
576 	}
577 
578 	spin_unlock_irq(&rtc->lock);
579 
580 	return 0;
581 }
582 
583 static int sh_rtc_irq_set_state(struct device *dev, int enabled)
584 {
585 	struct platform_device *pdev = to_platform_device(dev);
586 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
587 
588 	if (enabled) {
589 		rtc->periodic_freq |= PF_KOU;
590 		return sh_rtc_ioctl(dev, RTC_PIE_ON, 0);
591 	} else {
592 		rtc->periodic_freq &= ~PF_KOU;
593 		return sh_rtc_ioctl(dev, RTC_PIE_OFF, 0);
594 	}
595 }
596 
597 static int sh_rtc_irq_set_freq(struct device *dev, int freq)
598 {
599 	if (!is_power_of_2(freq))
600 		return -EINVAL;
601 	return sh_rtc_ioctl(dev, RTC_IRQP_SET, freq);
602 }
603 
604 static struct rtc_class_ops sh_rtc_ops = {
605 	.ioctl		= sh_rtc_ioctl,
606 	.read_time	= sh_rtc_read_time,
607 	.set_time	= sh_rtc_set_time,
608 	.read_alarm	= sh_rtc_read_alarm,
609 	.set_alarm	= sh_rtc_set_alarm,
610 	.irq_set_state	= sh_rtc_irq_set_state,
611 	.irq_set_freq	= sh_rtc_irq_set_freq,
612 	.proc		= sh_rtc_proc,
613 };
614 
615 static int __devinit sh_rtc_probe(struct platform_device *pdev)
616 {
617 	struct sh_rtc *rtc;
618 	struct resource *res;
619 	unsigned int tmp;
620 	int ret;
621 
622 	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
623 	if (unlikely(!rtc))
624 		return -ENOMEM;
625 
626 	spin_lock_init(&rtc->lock);
627 
628 	/* get periodic/carry/alarm irqs */
629 	ret = platform_get_irq(pdev, 0);
630 	if (unlikely(ret <= 0)) {
631 		ret = -ENOENT;
632 		dev_err(&pdev->dev, "No IRQ resource\n");
633 		goto err_badres;
634 	}
635 	rtc->periodic_irq = ret;
636 	rtc->carry_irq = platform_get_irq(pdev, 1);
637 	rtc->alarm_irq = platform_get_irq(pdev, 2);
638 
639 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
640 	if (unlikely(res == NULL)) {
641 		ret = -ENOENT;
642 		dev_err(&pdev->dev, "No IO resource\n");
643 		goto err_badres;
644 	}
645 
646 	rtc->regsize = res->end - res->start + 1;
647 
648 	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
649 	if (unlikely(!rtc->res)) {
650 		ret = -EBUSY;
651 		goto err_badres;
652 	}
653 
654 	rtc->regbase = ioremap_nocache(rtc->res->start, rtc->regsize);
655 	if (unlikely(!rtc->regbase)) {
656 		ret = -EINVAL;
657 		goto err_badmap;
658 	}
659 
660 	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
661 					   &sh_rtc_ops, THIS_MODULE);
662 	if (IS_ERR(rtc->rtc_dev)) {
663 		ret = PTR_ERR(rtc->rtc_dev);
664 		goto err_unmap;
665 	}
666 
667 	rtc->capabilities = RTC_DEF_CAPABILITIES;
668 	if (pdev->dev.platform_data) {
669 		struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
670 
671 		/*
672 		 * Some CPUs have special capabilities in addition to the
673 		 * default set. Add those in here.
674 		 */
675 		rtc->capabilities |= pinfo->capabilities;
676 	}
677 
678 	rtc->rtc_dev->max_user_freq = 256;
679 	rtc->rtc_dev->irq_freq = 1;
680 	rtc->periodic_freq = 0x60;
681 
682 	platform_set_drvdata(pdev, rtc);
683 
684 	if (rtc->carry_irq <= 0) {
685 		/* register shared periodic/carry/alarm irq */
686 		ret = request_irq(rtc->periodic_irq, sh_rtc_shared,
687 				  IRQF_DISABLED, "sh-rtc", rtc);
688 		if (unlikely(ret)) {
689 			dev_err(&pdev->dev,
690 				"request IRQ failed with %d, IRQ %d\n", ret,
691 				rtc->periodic_irq);
692 			goto err_unmap;
693 		}
694 	} else {
695 		/* register periodic/carry/alarm irqs */
696 		ret = request_irq(rtc->periodic_irq, sh_rtc_periodic,
697 				  IRQF_DISABLED, "sh-rtc period", rtc);
698 		if (unlikely(ret)) {
699 			dev_err(&pdev->dev,
700 				"request period IRQ failed with %d, IRQ %d\n",
701 				ret, rtc->periodic_irq);
702 			goto err_unmap;
703 		}
704 
705 		ret = request_irq(rtc->carry_irq, sh_rtc_interrupt,
706 				  IRQF_DISABLED, "sh-rtc carry", rtc);
707 		if (unlikely(ret)) {
708 			dev_err(&pdev->dev,
709 				"request carry IRQ failed with %d, IRQ %d\n",
710 				ret, rtc->carry_irq);
711 			free_irq(rtc->periodic_irq, rtc);
712 			goto err_unmap;
713 		}
714 
715 		ret = request_irq(rtc->alarm_irq, sh_rtc_alarm,
716 				  IRQF_DISABLED, "sh-rtc alarm", rtc);
717 		if (unlikely(ret)) {
718 			dev_err(&pdev->dev,
719 				"request alarm IRQ failed with %d, IRQ %d\n",
720 				ret, rtc->alarm_irq);
721 			free_irq(rtc->carry_irq, rtc);
722 			free_irq(rtc->periodic_irq, rtc);
723 			goto err_unmap;
724 		}
725 	}
726 
727 	tmp = readb(rtc->regbase + RCR1);
728 	tmp &= ~RCR1_CF;
729 	tmp |= RCR1_CIE;
730 	writeb(tmp, rtc->regbase + RCR1);
731 
732 	return 0;
733 
734 err_unmap:
735 	iounmap(rtc->regbase);
736 err_badmap:
737 	release_resource(rtc->res);
738 err_badres:
739 	kfree(rtc);
740 
741 	return ret;
742 }
743 
744 static int __devexit sh_rtc_remove(struct platform_device *pdev)
745 {
746 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
747 
748 	if (likely(rtc->rtc_dev))
749 		rtc_device_unregister(rtc->rtc_dev);
750 
751 	sh_rtc_setpie(&pdev->dev, 0);
752 	sh_rtc_setaie(&pdev->dev, 0);
753 
754 	free_irq(rtc->periodic_irq, rtc);
755 	if (rtc->carry_irq > 0) {
756 		free_irq(rtc->carry_irq, rtc);
757 		free_irq(rtc->alarm_irq, rtc);
758 	}
759 
760 	release_resource(rtc->res);
761 
762 	iounmap(rtc->regbase);
763 
764 	platform_set_drvdata(pdev, NULL);
765 
766 	kfree(rtc);
767 
768 	return 0;
769 }
770 static struct platform_driver sh_rtc_platform_driver = {
771 	.driver		= {
772 		.name	= DRV_NAME,
773 		.owner	= THIS_MODULE,
774 	},
775 	.probe		= sh_rtc_probe,
776 	.remove		= __devexit_p(sh_rtc_remove),
777 };
778 
779 static int __init sh_rtc_init(void)
780 {
781 	return platform_driver_register(&sh_rtc_platform_driver);
782 }
783 
784 static void __exit sh_rtc_exit(void)
785 {
786 	platform_driver_unregister(&sh_rtc_platform_driver);
787 }
788 
789 module_init(sh_rtc_init);
790 module_exit(sh_rtc_exit);
791 
792 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
793 MODULE_VERSION(DRV_VERSION);
794 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
795 	      "Jamie Lenehan <lenehan@twibble.org>, "
796 	      "Angelo Castello <angelo.castello@st.com>");
797 MODULE_LICENSE("GPL");
798 MODULE_ALIAS("platform:" DRV_NAME);
799