xref: /linux/drivers/rtc/rtc-sh.c (revision 8ec3b8432e4fe8d452f88f1ed9a3450e715bb797)
1 /*
2  * SuperH On-Chip RTC Support
3  *
4  * Copyright (C) 2006 - 2009  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 <linux/clk.h>
29 #include <linux/slab.h>
30 #include <asm/rtc.h>
31 
32 #define DRV_NAME	"sh-rtc"
33 #define DRV_VERSION	"0.2.3"
34 
35 #define RTC_REG(r)	((r) * rtc_reg_size)
36 
37 #define R64CNT		RTC_REG(0)
38 
39 #define RSECCNT		RTC_REG(1)	/* RTC sec */
40 #define RMINCNT		RTC_REG(2)	/* RTC min */
41 #define RHRCNT		RTC_REG(3)	/* RTC hour */
42 #define RWKCNT		RTC_REG(4)	/* RTC week */
43 #define RDAYCNT		RTC_REG(5)	/* RTC day */
44 #define RMONCNT		RTC_REG(6)	/* RTC month */
45 #define RYRCNT		RTC_REG(7)	/* RTC year */
46 #define RSECAR		RTC_REG(8)	/* ALARM sec */
47 #define RMINAR		RTC_REG(9)	/* ALARM min */
48 #define RHRAR		RTC_REG(10)	/* ALARM hour */
49 #define RWKAR		RTC_REG(11)	/* ALARM week */
50 #define RDAYAR		RTC_REG(12)	/* ALARM day */
51 #define RMONAR		RTC_REG(13)	/* ALARM month */
52 #define RCR1		RTC_REG(14)	/* Control */
53 #define RCR2		RTC_REG(15)	/* Control */
54 
55 /*
56  * Note on RYRAR and RCR3: Up until this point most of the register
57  * definitions are consistent across all of the available parts. However,
58  * the placement of the optional RYRAR and RCR3 (the RYRAR control
59  * register used to control RYRCNT/RYRAR compare) varies considerably
60  * across various parts, occasionally being mapped in to a completely
61  * unrelated address space. For proper RYRAR support a separate resource
62  * would have to be handed off, but as this is purely optional in
63  * practice, we simply opt not to support it, thereby keeping the code
64  * quite a bit more simplified.
65  */
66 
67 /* ALARM Bits - or with BCD encoded value */
68 #define AR_ENB		0x80	/* Enable for alarm cmp   */
69 
70 /* Period Bits */
71 #define PF_HP		0x100	/* Enable Half Period to support 8,32,128Hz */
72 #define PF_COUNT	0x200	/* Half periodic counter */
73 #define PF_OXS		0x400	/* Periodic One x Second */
74 #define PF_KOU		0x800	/* Kernel or User periodic request 1=kernel */
75 #define PF_MASK		0xf00
76 
77 /* RCR1 Bits */
78 #define RCR1_CF		0x80	/* Carry Flag             */
79 #define RCR1_CIE	0x10	/* Carry Interrupt Enable */
80 #define RCR1_AIE	0x08	/* Alarm Interrupt Enable */
81 #define RCR1_AF		0x01	/* Alarm Flag             */
82 
83 /* RCR2 Bits */
84 #define RCR2_PEF	0x80	/* PEriodic interrupt Flag */
85 #define RCR2_PESMASK	0x70	/* Periodic interrupt Set  */
86 #define RCR2_RTCEN	0x08	/* ENable RTC              */
87 #define RCR2_ADJ	0x04	/* ADJustment (30-second)  */
88 #define RCR2_RESET	0x02	/* Reset bit               */
89 #define RCR2_START	0x01	/* Start bit               */
90 
91 struct sh_rtc {
92 	void __iomem		*regbase;
93 	unsigned long		regsize;
94 	struct resource		*res;
95 	int			alarm_irq;
96 	int			periodic_irq;
97 	int			carry_irq;
98 	struct clk		*clk;
99 	struct rtc_device	*rtc_dev;
100 	spinlock_t		lock;
101 	unsigned long		capabilities;	/* See asm/rtc.h for cap bits */
102 	unsigned short		periodic_freq;
103 };
104 
105 static int __sh_rtc_interrupt(struct sh_rtc *rtc)
106 {
107 	unsigned int tmp, pending;
108 
109 	tmp = readb(rtc->regbase + RCR1);
110 	pending = tmp & RCR1_CF;
111 	tmp &= ~RCR1_CF;
112 	writeb(tmp, rtc->regbase + RCR1);
113 
114 	/* Users have requested One x Second IRQ */
115 	if (pending && rtc->periodic_freq & PF_OXS)
116 		rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
117 
118 	return pending;
119 }
120 
121 static int __sh_rtc_alarm(struct sh_rtc *rtc)
122 {
123 	unsigned int tmp, pending;
124 
125 	tmp = readb(rtc->regbase + RCR1);
126 	pending = tmp & RCR1_AF;
127 	tmp &= ~(RCR1_AF | RCR1_AIE);
128 	writeb(tmp, rtc->regbase + RCR1);
129 
130 	if (pending)
131 		rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
132 
133 	return pending;
134 }
135 
136 static int __sh_rtc_periodic(struct sh_rtc *rtc)
137 {
138 	struct rtc_device *rtc_dev = rtc->rtc_dev;
139 	struct rtc_task *irq_task;
140 	unsigned int tmp, pending;
141 
142 	tmp = readb(rtc->regbase + RCR2);
143 	pending = tmp & RCR2_PEF;
144 	tmp &= ~RCR2_PEF;
145 	writeb(tmp, rtc->regbase + RCR2);
146 
147 	if (!pending)
148 		return 0;
149 
150 	/* Half period enabled than one skipped and the next notified */
151 	if ((rtc->periodic_freq & PF_HP) && (rtc->periodic_freq & PF_COUNT))
152 		rtc->periodic_freq &= ~PF_COUNT;
153 	else {
154 		if (rtc->periodic_freq & PF_HP)
155 			rtc->periodic_freq |= PF_COUNT;
156 		if (rtc->periodic_freq & PF_KOU) {
157 			spin_lock(&rtc_dev->irq_task_lock);
158 			irq_task = rtc_dev->irq_task;
159 			if (irq_task)
160 				irq_task->func(irq_task->private_data);
161 			spin_unlock(&rtc_dev->irq_task_lock);
162 		} else
163 			rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
164 	}
165 
166 	return pending;
167 }
168 
169 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
170 {
171 	struct sh_rtc *rtc = dev_id;
172 	int ret;
173 
174 	spin_lock(&rtc->lock);
175 	ret = __sh_rtc_interrupt(rtc);
176 	spin_unlock(&rtc->lock);
177 
178 	return IRQ_RETVAL(ret);
179 }
180 
181 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
182 {
183 	struct sh_rtc *rtc = dev_id;
184 	int ret;
185 
186 	spin_lock(&rtc->lock);
187 	ret = __sh_rtc_alarm(rtc);
188 	spin_unlock(&rtc->lock);
189 
190 	return IRQ_RETVAL(ret);
191 }
192 
193 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
194 {
195 	struct sh_rtc *rtc = dev_id;
196 	int ret;
197 
198 	spin_lock(&rtc->lock);
199 	ret = __sh_rtc_periodic(rtc);
200 	spin_unlock(&rtc->lock);
201 
202 	return IRQ_RETVAL(ret);
203 }
204 
205 static irqreturn_t sh_rtc_shared(int irq, void *dev_id)
206 {
207 	struct sh_rtc *rtc = dev_id;
208 	int ret;
209 
210 	spin_lock(&rtc->lock);
211 	ret = __sh_rtc_interrupt(rtc);
212 	ret |= __sh_rtc_alarm(rtc);
213 	ret |= __sh_rtc_periodic(rtc);
214 	spin_unlock(&rtc->lock);
215 
216 	return IRQ_RETVAL(ret);
217 }
218 
219 static int sh_rtc_irq_set_state(struct device *dev, int enable)
220 {
221 	struct sh_rtc *rtc = dev_get_drvdata(dev);
222 	unsigned int tmp;
223 
224 	spin_lock_irq(&rtc->lock);
225 
226 	tmp = readb(rtc->regbase + RCR2);
227 
228 	if (enable) {
229 		rtc->periodic_freq |= PF_KOU;
230 		tmp &= ~RCR2_PEF;	/* Clear PES bit */
231 		tmp |= (rtc->periodic_freq & ~PF_HP);	/* Set PES2-0 */
232 	} else {
233 		rtc->periodic_freq &= ~PF_KOU;
234 		tmp &= ~(RCR2_PESMASK | RCR2_PEF);
235 	}
236 
237 	writeb(tmp, rtc->regbase + RCR2);
238 
239 	spin_unlock_irq(&rtc->lock);
240 
241 	return 0;
242 }
243 
244 static int sh_rtc_irq_set_freq(struct device *dev, int freq)
245 {
246 	struct sh_rtc *rtc = dev_get_drvdata(dev);
247 	int tmp, ret = 0;
248 
249 	spin_lock_irq(&rtc->lock);
250 	tmp = rtc->periodic_freq & PF_MASK;
251 
252 	switch (freq) {
253 	case 0:
254 		rtc->periodic_freq = 0x00;
255 		break;
256 	case 1:
257 		rtc->periodic_freq = 0x60;
258 		break;
259 	case 2:
260 		rtc->periodic_freq = 0x50;
261 		break;
262 	case 4:
263 		rtc->periodic_freq = 0x40;
264 		break;
265 	case 8:
266 		rtc->periodic_freq = 0x30 | PF_HP;
267 		break;
268 	case 16:
269 		rtc->periodic_freq = 0x30;
270 		break;
271 	case 32:
272 		rtc->periodic_freq = 0x20 | PF_HP;
273 		break;
274 	case 64:
275 		rtc->periodic_freq = 0x20;
276 		break;
277 	case 128:
278 		rtc->periodic_freq = 0x10 | PF_HP;
279 		break;
280 	case 256:
281 		rtc->periodic_freq = 0x10;
282 		break;
283 	default:
284 		ret = -ENOTSUPP;
285 	}
286 
287 	if (ret == 0)
288 		rtc->periodic_freq |= tmp;
289 
290 	spin_unlock_irq(&rtc->lock);
291 	return ret;
292 }
293 
294 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
295 {
296 	struct sh_rtc *rtc = dev_get_drvdata(dev);
297 	unsigned int tmp;
298 
299 	spin_lock_irq(&rtc->lock);
300 
301 	tmp = readb(rtc->regbase + RCR1);
302 
303 	if (enable)
304 		tmp |= RCR1_AIE;
305 	else
306 		tmp &= ~RCR1_AIE;
307 
308 	writeb(tmp, rtc->regbase + RCR1);
309 
310 	spin_unlock_irq(&rtc->lock);
311 }
312 
313 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
314 {
315 	struct sh_rtc *rtc = dev_get_drvdata(dev);
316 	unsigned int tmp;
317 
318 	tmp = readb(rtc->regbase + RCR1);
319 	seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no");
320 
321 	tmp = readb(rtc->regbase + RCR2);
322 	seq_printf(seq, "periodic_IRQ\t: %s\n",
323 		   (tmp & RCR2_PESMASK) ? "yes" : "no");
324 
325 	return 0;
326 }
327 
328 static inline void sh_rtc_setcie(struct device *dev, unsigned int enable)
329 {
330 	struct sh_rtc *rtc = dev_get_drvdata(dev);
331 	unsigned int tmp;
332 
333 	spin_lock_irq(&rtc->lock);
334 
335 	tmp = readb(rtc->regbase + RCR1);
336 
337 	if (!enable)
338 		tmp &= ~RCR1_CIE;
339 	else
340 		tmp |= RCR1_CIE;
341 
342 	writeb(tmp, rtc->regbase + RCR1);
343 
344 	spin_unlock_irq(&rtc->lock);
345 }
346 
347 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
348 {
349 	struct sh_rtc *rtc = dev_get_drvdata(dev);
350 	unsigned int ret = 0;
351 
352 	switch (cmd) {
353 	case RTC_UIE_OFF:
354 		rtc->periodic_freq &= ~PF_OXS;
355 		sh_rtc_setcie(dev, 0);
356 		break;
357 	case RTC_UIE_ON:
358 		rtc->periodic_freq |= PF_OXS;
359 		sh_rtc_setcie(dev, 1);
360 		break;
361 	default:
362 		ret = -ENOIOCTLCMD;
363 	}
364 
365 	return ret;
366 }
367 
368 static int sh_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
369 {
370 	sh_rtc_setaie(dev, enabled);
371 	return 0;
372 }
373 
374 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
375 {
376 	struct platform_device *pdev = to_platform_device(dev);
377 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
378 	unsigned int sec128, sec2, yr, yr100, cf_bit;
379 
380 	do {
381 		unsigned int tmp;
382 
383 		spin_lock_irq(&rtc->lock);
384 
385 		tmp = readb(rtc->regbase + RCR1);
386 		tmp &= ~RCR1_CF; /* Clear CF-bit */
387 		tmp |= RCR1_CIE;
388 		writeb(tmp, rtc->regbase + RCR1);
389 
390 		sec128 = readb(rtc->regbase + R64CNT);
391 
392 		tm->tm_sec	= bcd2bin(readb(rtc->regbase + RSECCNT));
393 		tm->tm_min	= bcd2bin(readb(rtc->regbase + RMINCNT));
394 		tm->tm_hour	= bcd2bin(readb(rtc->regbase + RHRCNT));
395 		tm->tm_wday	= bcd2bin(readb(rtc->regbase + RWKCNT));
396 		tm->tm_mday	= bcd2bin(readb(rtc->regbase + RDAYCNT));
397 		tm->tm_mon	= bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
398 
399 		if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
400 			yr  = readw(rtc->regbase + RYRCNT);
401 			yr100 = bcd2bin(yr >> 8);
402 			yr &= 0xff;
403 		} else {
404 			yr  = readb(rtc->regbase + RYRCNT);
405 			yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
406 		}
407 
408 		tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
409 
410 		sec2 = readb(rtc->regbase + R64CNT);
411 		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
412 
413 		spin_unlock_irq(&rtc->lock);
414 	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
415 
416 #if RTC_BIT_INVERTED != 0
417 	if ((sec128 & RTC_BIT_INVERTED))
418 		tm->tm_sec--;
419 #endif
420 
421 	/* only keep the carry interrupt enabled if UIE is on */
422 	if (!(rtc->periodic_freq & PF_OXS))
423 		sh_rtc_setcie(dev, 0);
424 
425 	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
426 		"mday=%d, mon=%d, year=%d, wday=%d\n",
427 		__func__,
428 		tm->tm_sec, tm->tm_min, tm->tm_hour,
429 		tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
430 
431 	return rtc_valid_tm(tm);
432 }
433 
434 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
435 {
436 	struct platform_device *pdev = to_platform_device(dev);
437 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
438 	unsigned int tmp;
439 	int year;
440 
441 	spin_lock_irq(&rtc->lock);
442 
443 	/* Reset pre-scaler & stop RTC */
444 	tmp = readb(rtc->regbase + RCR2);
445 	tmp |= RCR2_RESET;
446 	tmp &= ~RCR2_START;
447 	writeb(tmp, rtc->regbase + RCR2);
448 
449 	writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
450 	writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
451 	writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
452 	writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
453 	writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
454 	writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
455 
456 	if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
457 		year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
458 			bin2bcd(tm->tm_year % 100);
459 		writew(year, rtc->regbase + RYRCNT);
460 	} else {
461 		year = tm->tm_year % 100;
462 		writeb(bin2bcd(year), rtc->regbase + RYRCNT);
463 	}
464 
465 	/* Start RTC */
466 	tmp = readb(rtc->regbase + RCR2);
467 	tmp &= ~RCR2_RESET;
468 	tmp |= RCR2_RTCEN | RCR2_START;
469 	writeb(tmp, rtc->regbase + RCR2);
470 
471 	spin_unlock_irq(&rtc->lock);
472 
473 	return 0;
474 }
475 
476 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
477 {
478 	unsigned int byte;
479 	int value = 0xff;	/* return 0xff for ignored values */
480 
481 	byte = readb(rtc->regbase + reg_off);
482 	if (byte & AR_ENB) {
483 		byte &= ~AR_ENB;	/* strip the enable bit */
484 		value = bcd2bin(byte);
485 	}
486 
487 	return value;
488 }
489 
490 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
491 {
492 	struct platform_device *pdev = to_platform_device(dev);
493 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
494 	struct rtc_time *tm = &wkalrm->time;
495 
496 	spin_lock_irq(&rtc->lock);
497 
498 	tm->tm_sec	= sh_rtc_read_alarm_value(rtc, RSECAR);
499 	tm->tm_min	= sh_rtc_read_alarm_value(rtc, RMINAR);
500 	tm->tm_hour	= sh_rtc_read_alarm_value(rtc, RHRAR);
501 	tm->tm_wday	= sh_rtc_read_alarm_value(rtc, RWKAR);
502 	tm->tm_mday	= sh_rtc_read_alarm_value(rtc, RDAYAR);
503 	tm->tm_mon	= sh_rtc_read_alarm_value(rtc, RMONAR);
504 	if (tm->tm_mon > 0)
505 		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
506 	tm->tm_year     = 0xffff;
507 
508 	wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
509 
510 	spin_unlock_irq(&rtc->lock);
511 
512 	return 0;
513 }
514 
515 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
516 					    int value, int reg_off)
517 {
518 	/* < 0 for a value that is ignored */
519 	if (value < 0)
520 		writeb(0, rtc->regbase + reg_off);
521 	else
522 		writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
523 }
524 
525 static int sh_rtc_check_alarm(struct rtc_time *tm)
526 {
527 	/*
528 	 * The original rtc says anything > 0xc0 is "don't care" or "match
529 	 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
530 	 * The original rtc doesn't support years - some things use -1 and
531 	 * some 0xffff. We use -1 to make out tests easier.
532 	 */
533 	if (tm->tm_year == 0xffff)
534 		tm->tm_year = -1;
535 	if (tm->tm_mon >= 0xff)
536 		tm->tm_mon = -1;
537 	if (tm->tm_mday >= 0xff)
538 		tm->tm_mday = -1;
539 	if (tm->tm_wday >= 0xff)
540 		tm->tm_wday = -1;
541 	if (tm->tm_hour >= 0xff)
542 		tm->tm_hour = -1;
543 	if (tm->tm_min >= 0xff)
544 		tm->tm_min = -1;
545 	if (tm->tm_sec >= 0xff)
546 		tm->tm_sec = -1;
547 
548 	if (tm->tm_year > 9999 ||
549 		tm->tm_mon >= 12 ||
550 		tm->tm_mday == 0 || tm->tm_mday >= 32 ||
551 		tm->tm_wday >= 7 ||
552 		tm->tm_hour >= 24 ||
553 		tm->tm_min >= 60 ||
554 		tm->tm_sec >= 60)
555 		return -EINVAL;
556 
557 	return 0;
558 }
559 
560 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
561 {
562 	struct platform_device *pdev = to_platform_device(dev);
563 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
564 	unsigned int rcr1;
565 	struct rtc_time *tm = &wkalrm->time;
566 	int mon, err;
567 
568 	err = sh_rtc_check_alarm(tm);
569 	if (unlikely(err < 0))
570 		return err;
571 
572 	spin_lock_irq(&rtc->lock);
573 
574 	/* disable alarm interrupt and clear the alarm flag */
575 	rcr1 = readb(rtc->regbase + RCR1);
576 	rcr1 &= ~(RCR1_AF | RCR1_AIE);
577 	writeb(rcr1, rtc->regbase + RCR1);
578 
579 	/* set alarm time */
580 	sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
581 	sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
582 	sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
583 	sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
584 	sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
585 	mon = tm->tm_mon;
586 	if (mon >= 0)
587 		mon += 1;
588 	sh_rtc_write_alarm_value(rtc, mon, RMONAR);
589 
590 	if (wkalrm->enabled) {
591 		rcr1 |= RCR1_AIE;
592 		writeb(rcr1, rtc->regbase + RCR1);
593 	}
594 
595 	spin_unlock_irq(&rtc->lock);
596 
597 	return 0;
598 }
599 
600 static struct rtc_class_ops sh_rtc_ops = {
601 	.ioctl		= sh_rtc_ioctl,
602 	.read_time	= sh_rtc_read_time,
603 	.set_time	= sh_rtc_set_time,
604 	.read_alarm	= sh_rtc_read_alarm,
605 	.set_alarm	= sh_rtc_set_alarm,
606 	.irq_set_state	= sh_rtc_irq_set_state,
607 	.irq_set_freq	= sh_rtc_irq_set_freq,
608 	.proc		= sh_rtc_proc,
609 	.alarm_irq_enable = sh_rtc_alarm_irq_enable,
610 };
611 
612 static int __init sh_rtc_probe(struct platform_device *pdev)
613 {
614 	struct sh_rtc *rtc;
615 	struct resource *res;
616 	struct rtc_time r;
617 	char clk_name[6];
618 	int clk_id, ret;
619 
620 	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
621 	if (unlikely(!rtc))
622 		return -ENOMEM;
623 
624 	spin_lock_init(&rtc->lock);
625 
626 	/* get periodic/carry/alarm irqs */
627 	ret = platform_get_irq(pdev, 0);
628 	if (unlikely(ret <= 0)) {
629 		ret = -ENOENT;
630 		dev_err(&pdev->dev, "No IRQ resource\n");
631 		goto err_badres;
632 	}
633 
634 	rtc->periodic_irq = ret;
635 	rtc->carry_irq = platform_get_irq(pdev, 1);
636 	rtc->alarm_irq = platform_get_irq(pdev, 2);
637 
638 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
639 	if (unlikely(res == NULL)) {
640 		ret = -ENOENT;
641 		dev_err(&pdev->dev, "No IO resource\n");
642 		goto err_badres;
643 	}
644 
645 	rtc->regsize = resource_size(res);
646 
647 	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
648 	if (unlikely(!rtc->res)) {
649 		ret = -EBUSY;
650 		goto err_badres;
651 	}
652 
653 	rtc->regbase = ioremap_nocache(rtc->res->start, rtc->regsize);
654 	if (unlikely(!rtc->regbase)) {
655 		ret = -EINVAL;
656 		goto err_badmap;
657 	}
658 
659 	clk_id = pdev->id;
660 	/* With a single device, the clock id is still "rtc0" */
661 	if (clk_id < 0)
662 		clk_id = 0;
663 
664 	snprintf(clk_name, sizeof(clk_name), "rtc%d", clk_id);
665 
666 	rtc->clk = clk_get(&pdev->dev, clk_name);
667 	if (IS_ERR(rtc->clk)) {
668 		/*
669 		 * No error handling for rtc->clk intentionally, not all
670 		 * platforms will have a unique clock for the RTC, and
671 		 * the clk API can handle the struct clk pointer being
672 		 * NULL.
673 		 */
674 		rtc->clk = NULL;
675 	}
676 
677 	clk_enable(rtc->clk);
678 
679 	rtc->capabilities = RTC_DEF_CAPABILITIES;
680 	if (pdev->dev.platform_data) {
681 		struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
682 
683 		/*
684 		 * Some CPUs have special capabilities in addition to the
685 		 * default set. Add those in here.
686 		 */
687 		rtc->capabilities |= pinfo->capabilities;
688 	}
689 
690 	if (rtc->carry_irq <= 0) {
691 		/* register shared periodic/carry/alarm irq */
692 		ret = request_irq(rtc->periodic_irq, sh_rtc_shared,
693 				  IRQF_DISABLED, "sh-rtc", rtc);
694 		if (unlikely(ret)) {
695 			dev_err(&pdev->dev,
696 				"request IRQ failed with %d, IRQ %d\n", ret,
697 				rtc->periodic_irq);
698 			goto err_unmap;
699 		}
700 	} else {
701 		/* register periodic/carry/alarm irqs */
702 		ret = request_irq(rtc->periodic_irq, sh_rtc_periodic,
703 				  IRQF_DISABLED, "sh-rtc period", rtc);
704 		if (unlikely(ret)) {
705 			dev_err(&pdev->dev,
706 				"request period IRQ failed with %d, IRQ %d\n",
707 				ret, rtc->periodic_irq);
708 			goto err_unmap;
709 		}
710 
711 		ret = request_irq(rtc->carry_irq, sh_rtc_interrupt,
712 				  IRQF_DISABLED, "sh-rtc carry", rtc);
713 		if (unlikely(ret)) {
714 			dev_err(&pdev->dev,
715 				"request carry IRQ failed with %d, IRQ %d\n",
716 				ret, rtc->carry_irq);
717 			free_irq(rtc->periodic_irq, rtc);
718 			goto err_unmap;
719 		}
720 
721 		ret = request_irq(rtc->alarm_irq, sh_rtc_alarm,
722 				  IRQF_DISABLED, "sh-rtc alarm", rtc);
723 		if (unlikely(ret)) {
724 			dev_err(&pdev->dev,
725 				"request alarm IRQ failed with %d, IRQ %d\n",
726 				ret, rtc->alarm_irq);
727 			free_irq(rtc->carry_irq, rtc);
728 			free_irq(rtc->periodic_irq, rtc);
729 			goto err_unmap;
730 		}
731 	}
732 
733 	platform_set_drvdata(pdev, rtc);
734 
735 	/* everything disabled by default */
736 	sh_rtc_irq_set_freq(&pdev->dev, 0);
737 	sh_rtc_irq_set_state(&pdev->dev, 0);
738 	sh_rtc_setaie(&pdev->dev, 0);
739 	sh_rtc_setcie(&pdev->dev, 0);
740 
741 	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
742 					   &sh_rtc_ops, THIS_MODULE);
743 	if (IS_ERR(rtc->rtc_dev)) {
744 		ret = PTR_ERR(rtc->rtc_dev);
745 		free_irq(rtc->periodic_irq, rtc);
746 		free_irq(rtc->carry_irq, rtc);
747 		free_irq(rtc->alarm_irq, rtc);
748 		goto err_unmap;
749 	}
750 
751 	rtc->rtc_dev->max_user_freq = 256;
752 
753 	/* reset rtc to epoch 0 if time is invalid */
754 	if (rtc_read_time(rtc->rtc_dev, &r) < 0) {
755 		rtc_time_to_tm(0, &r);
756 		rtc_set_time(rtc->rtc_dev, &r);
757 	}
758 
759 	device_init_wakeup(&pdev->dev, 1);
760 	return 0;
761 
762 err_unmap:
763 	clk_disable(rtc->clk);
764 	clk_put(rtc->clk);
765 	iounmap(rtc->regbase);
766 err_badmap:
767 	release_mem_region(rtc->res->start, rtc->regsize);
768 err_badres:
769 	kfree(rtc);
770 
771 	return ret;
772 }
773 
774 static int __exit sh_rtc_remove(struct platform_device *pdev)
775 {
776 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
777 
778 	rtc_device_unregister(rtc->rtc_dev);
779 	sh_rtc_irq_set_state(&pdev->dev, 0);
780 
781 	sh_rtc_setaie(&pdev->dev, 0);
782 	sh_rtc_setcie(&pdev->dev, 0);
783 
784 	free_irq(rtc->periodic_irq, rtc);
785 
786 	if (rtc->carry_irq > 0) {
787 		free_irq(rtc->carry_irq, rtc);
788 		free_irq(rtc->alarm_irq, rtc);
789 	}
790 
791 	iounmap(rtc->regbase);
792 	release_mem_region(rtc->res->start, rtc->regsize);
793 
794 	clk_disable(rtc->clk);
795 	clk_put(rtc->clk);
796 
797 	platform_set_drvdata(pdev, NULL);
798 
799 	kfree(rtc);
800 
801 	return 0;
802 }
803 
804 static void sh_rtc_set_irq_wake(struct device *dev, int enabled)
805 {
806 	struct platform_device *pdev = to_platform_device(dev);
807 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
808 
809 	set_irq_wake(rtc->periodic_irq, enabled);
810 
811 	if (rtc->carry_irq > 0) {
812 		set_irq_wake(rtc->carry_irq, enabled);
813 		set_irq_wake(rtc->alarm_irq, enabled);
814 	}
815 }
816 
817 static int sh_rtc_suspend(struct device *dev)
818 {
819 	if (device_may_wakeup(dev))
820 		sh_rtc_set_irq_wake(dev, 1);
821 
822 	return 0;
823 }
824 
825 static int sh_rtc_resume(struct device *dev)
826 {
827 	if (device_may_wakeup(dev))
828 		sh_rtc_set_irq_wake(dev, 0);
829 
830 	return 0;
831 }
832 
833 static const struct dev_pm_ops sh_rtc_dev_pm_ops = {
834 	.suspend = sh_rtc_suspend,
835 	.resume = sh_rtc_resume,
836 };
837 
838 static struct platform_driver sh_rtc_platform_driver = {
839 	.driver		= {
840 		.name	= DRV_NAME,
841 		.owner	= THIS_MODULE,
842 		.pm	= &sh_rtc_dev_pm_ops,
843 	},
844 	.remove		= __exit_p(sh_rtc_remove),
845 };
846 
847 static int __init sh_rtc_init(void)
848 {
849 	return platform_driver_probe(&sh_rtc_platform_driver, sh_rtc_probe);
850 }
851 
852 static void __exit sh_rtc_exit(void)
853 {
854 	platform_driver_unregister(&sh_rtc_platform_driver);
855 }
856 
857 module_init(sh_rtc_init);
858 module_exit(sh_rtc_exit);
859 
860 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
861 MODULE_VERSION(DRV_VERSION);
862 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
863 	      "Jamie Lenehan <lenehan@twibble.org>, "
864 	      "Angelo Castello <angelo.castello@st.com>");
865 MODULE_LICENSE("GPL");
866 MODULE_ALIAS("platform:" DRV_NAME);
867