xref: /openbmc/linux/drivers/rtc/rtc-sh.c (revision b627b4ed)
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	"0.2.1"
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 inline void sh_rtc_setcie(struct device *dev, unsigned int enable)
323 {
324 	struct sh_rtc *rtc = dev_get_drvdata(dev);
325 	unsigned int tmp;
326 
327 	spin_lock_irq(&rtc->lock);
328 
329 	tmp = readb(rtc->regbase + RCR1);
330 
331 	if (!enable)
332 		tmp &= ~RCR1_CIE;
333 	else
334 		tmp |= RCR1_CIE;
335 
336 	writeb(tmp, rtc->regbase + RCR1);
337 
338 	spin_unlock_irq(&rtc->lock);
339 }
340 
341 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
342 {
343 	struct sh_rtc *rtc = dev_get_drvdata(dev);
344 	unsigned int ret = 0;
345 
346 	switch (cmd) {
347 	case RTC_PIE_OFF:
348 	case RTC_PIE_ON:
349 		sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
350 		break;
351 	case RTC_AIE_OFF:
352 	case RTC_AIE_ON:
353 		sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
354 		break;
355 	case RTC_UIE_OFF:
356 		rtc->periodic_freq &= ~PF_OXS;
357 		sh_rtc_setcie(dev, 0);
358 		break;
359 	case RTC_UIE_ON:
360 		rtc->periodic_freq |= PF_OXS;
361 		sh_rtc_setcie(dev, 1);
362 		break;
363 	case RTC_IRQP_READ:
364 		ret = put_user(rtc->rtc_dev->irq_freq,
365 			       (unsigned long __user *)arg);
366 		break;
367 	case RTC_IRQP_SET:
368 		ret = sh_rtc_setfreq(dev, arg);
369 		break;
370 	default:
371 		ret = -ENOIOCTLCMD;
372 	}
373 
374 	return ret;
375 }
376 
377 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
378 {
379 	struct platform_device *pdev = to_platform_device(dev);
380 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
381 	unsigned int sec128, sec2, yr, yr100, cf_bit;
382 
383 	do {
384 		unsigned int tmp;
385 
386 		spin_lock_irq(&rtc->lock);
387 
388 		tmp = readb(rtc->regbase + RCR1);
389 		tmp &= ~RCR1_CF; /* Clear CF-bit */
390 		tmp |= RCR1_CIE;
391 		writeb(tmp, rtc->regbase + RCR1);
392 
393 		sec128 = readb(rtc->regbase + R64CNT);
394 
395 		tm->tm_sec	= bcd2bin(readb(rtc->regbase + RSECCNT));
396 		tm->tm_min	= bcd2bin(readb(rtc->regbase + RMINCNT));
397 		tm->tm_hour	= bcd2bin(readb(rtc->regbase + RHRCNT));
398 		tm->tm_wday	= bcd2bin(readb(rtc->regbase + RWKCNT));
399 		tm->tm_mday	= bcd2bin(readb(rtc->regbase + RDAYCNT));
400 		tm->tm_mon	= bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
401 
402 		if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
403 			yr  = readw(rtc->regbase + RYRCNT);
404 			yr100 = bcd2bin(yr >> 8);
405 			yr &= 0xff;
406 		} else {
407 			yr  = readb(rtc->regbase + RYRCNT);
408 			yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
409 		}
410 
411 		tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
412 
413 		sec2 = readb(rtc->regbase + R64CNT);
414 		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
415 
416 		spin_unlock_irq(&rtc->lock);
417 	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
418 
419 #if RTC_BIT_INVERTED != 0
420 	if ((sec128 & RTC_BIT_INVERTED))
421 		tm->tm_sec--;
422 #endif
423 
424 	/* only keep the carry interrupt enabled if UIE is on */
425 	if (!(rtc->periodic_freq & PF_OXS))
426 		sh_rtc_setcie(dev, 0);
427 
428 	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
429 		"mday=%d, mon=%d, year=%d, wday=%d\n",
430 		__func__,
431 		tm->tm_sec, tm->tm_min, tm->tm_hour,
432 		tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
433 
434 	return rtc_valid_tm(tm);
435 }
436 
437 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
438 {
439 	struct platform_device *pdev = to_platform_device(dev);
440 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
441 	unsigned int tmp;
442 	int year;
443 
444 	spin_lock_irq(&rtc->lock);
445 
446 	/* Reset pre-scaler & stop RTC */
447 	tmp = readb(rtc->regbase + RCR2);
448 	tmp |= RCR2_RESET;
449 	tmp &= ~RCR2_START;
450 	writeb(tmp, rtc->regbase + RCR2);
451 
452 	writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
453 	writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
454 	writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
455 	writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
456 	writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
457 	writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
458 
459 	if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
460 		year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
461 			bin2bcd(tm->tm_year % 100);
462 		writew(year, rtc->regbase + RYRCNT);
463 	} else {
464 		year = tm->tm_year % 100;
465 		writeb(bin2bcd(year), rtc->regbase + RYRCNT);
466 	}
467 
468 	/* Start RTC */
469 	tmp = readb(rtc->regbase + RCR2);
470 	tmp &= ~RCR2_RESET;
471 	tmp |= RCR2_RTCEN | RCR2_START;
472 	writeb(tmp, rtc->regbase + RCR2);
473 
474 	spin_unlock_irq(&rtc->lock);
475 
476 	return 0;
477 }
478 
479 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
480 {
481 	unsigned int byte;
482 	int value = 0xff;	/* return 0xff for ignored values */
483 
484 	byte = readb(rtc->regbase + reg_off);
485 	if (byte & AR_ENB) {
486 		byte &= ~AR_ENB;	/* strip the enable bit */
487 		value = bcd2bin(byte);
488 	}
489 
490 	return value;
491 }
492 
493 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
494 {
495 	struct platform_device *pdev = to_platform_device(dev);
496 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
497 	struct rtc_time *tm = &wkalrm->time;
498 
499 	spin_lock_irq(&rtc->lock);
500 
501 	tm->tm_sec	= sh_rtc_read_alarm_value(rtc, RSECAR);
502 	tm->tm_min	= sh_rtc_read_alarm_value(rtc, RMINAR);
503 	tm->tm_hour	= sh_rtc_read_alarm_value(rtc, RHRAR);
504 	tm->tm_wday	= sh_rtc_read_alarm_value(rtc, RWKAR);
505 	tm->tm_mday	= sh_rtc_read_alarm_value(rtc, RDAYAR);
506 	tm->tm_mon	= sh_rtc_read_alarm_value(rtc, RMONAR);
507 	if (tm->tm_mon > 0)
508 		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
509 	tm->tm_year     = 0xffff;
510 
511 	wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
512 
513 	spin_unlock_irq(&rtc->lock);
514 
515 	return 0;
516 }
517 
518 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
519 					    int value, int reg_off)
520 {
521 	/* < 0 for a value that is ignored */
522 	if (value < 0)
523 		writeb(0, rtc->regbase + reg_off);
524 	else
525 		writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
526 }
527 
528 static int sh_rtc_check_alarm(struct rtc_time *tm)
529 {
530 	/*
531 	 * The original rtc says anything > 0xc0 is "don't care" or "match
532 	 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
533 	 * The original rtc doesn't support years - some things use -1 and
534 	 * some 0xffff. We use -1 to make out tests easier.
535 	 */
536 	if (tm->tm_year == 0xffff)
537 		tm->tm_year = -1;
538 	if (tm->tm_mon >= 0xff)
539 		tm->tm_mon = -1;
540 	if (tm->tm_mday >= 0xff)
541 		tm->tm_mday = -1;
542 	if (tm->tm_wday >= 0xff)
543 		tm->tm_wday = -1;
544 	if (tm->tm_hour >= 0xff)
545 		tm->tm_hour = -1;
546 	if (tm->tm_min >= 0xff)
547 		tm->tm_min = -1;
548 	if (tm->tm_sec >= 0xff)
549 		tm->tm_sec = -1;
550 
551 	if (tm->tm_year > 9999 ||
552 		tm->tm_mon >= 12 ||
553 		tm->tm_mday == 0 || tm->tm_mday >= 32 ||
554 		tm->tm_wday >= 7 ||
555 		tm->tm_hour >= 24 ||
556 		tm->tm_min >= 60 ||
557 		tm->tm_sec >= 60)
558 		return -EINVAL;
559 
560 	return 0;
561 }
562 
563 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
564 {
565 	struct platform_device *pdev = to_platform_device(dev);
566 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
567 	unsigned int rcr1;
568 	struct rtc_time *tm = &wkalrm->time;
569 	int mon, err;
570 
571 	err = sh_rtc_check_alarm(tm);
572 	if (unlikely(err < 0))
573 		return err;
574 
575 	spin_lock_irq(&rtc->lock);
576 
577 	/* disable alarm interrupt and clear the alarm flag */
578 	rcr1 = readb(rtc->regbase + RCR1);
579 	rcr1 &= ~(RCR1_AF | RCR1_AIE);
580 	writeb(rcr1, rtc->regbase + RCR1);
581 
582 	/* set alarm time */
583 	sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
584 	sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
585 	sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
586 	sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
587 	sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
588 	mon = tm->tm_mon;
589 	if (mon >= 0)
590 		mon += 1;
591 	sh_rtc_write_alarm_value(rtc, mon, RMONAR);
592 
593 	if (wkalrm->enabled) {
594 		rcr1 |= RCR1_AIE;
595 		writeb(rcr1, rtc->regbase + RCR1);
596 	}
597 
598 	spin_unlock_irq(&rtc->lock);
599 
600 	return 0;
601 }
602 
603 static int sh_rtc_irq_set_state(struct device *dev, int enabled)
604 {
605 	struct platform_device *pdev = to_platform_device(dev);
606 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
607 
608 	if (enabled) {
609 		rtc->periodic_freq |= PF_KOU;
610 		return sh_rtc_ioctl(dev, RTC_PIE_ON, 0);
611 	} else {
612 		rtc->periodic_freq &= ~PF_KOU;
613 		return sh_rtc_ioctl(dev, RTC_PIE_OFF, 0);
614 	}
615 }
616 
617 static int sh_rtc_irq_set_freq(struct device *dev, int freq)
618 {
619 	if (!is_power_of_2(freq))
620 		return -EINVAL;
621 	return sh_rtc_ioctl(dev, RTC_IRQP_SET, freq);
622 }
623 
624 static struct rtc_class_ops sh_rtc_ops = {
625 	.ioctl		= sh_rtc_ioctl,
626 	.read_time	= sh_rtc_read_time,
627 	.set_time	= sh_rtc_set_time,
628 	.read_alarm	= sh_rtc_read_alarm,
629 	.set_alarm	= sh_rtc_set_alarm,
630 	.irq_set_state	= sh_rtc_irq_set_state,
631 	.irq_set_freq	= sh_rtc_irq_set_freq,
632 	.proc		= sh_rtc_proc,
633 };
634 
635 static int __devinit sh_rtc_probe(struct platform_device *pdev)
636 {
637 	struct sh_rtc *rtc;
638 	struct resource *res;
639 	struct rtc_time r;
640 	int ret;
641 
642 	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
643 	if (unlikely(!rtc))
644 		return -ENOMEM;
645 
646 	spin_lock_init(&rtc->lock);
647 
648 	/* get periodic/carry/alarm irqs */
649 	ret = platform_get_irq(pdev, 0);
650 	if (unlikely(ret <= 0)) {
651 		ret = -ENOENT;
652 		dev_err(&pdev->dev, "No IRQ resource\n");
653 		goto err_badres;
654 	}
655 	rtc->periodic_irq = ret;
656 	rtc->carry_irq = platform_get_irq(pdev, 1);
657 	rtc->alarm_irq = platform_get_irq(pdev, 2);
658 
659 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
660 	if (unlikely(res == NULL)) {
661 		ret = -ENOENT;
662 		dev_err(&pdev->dev, "No IO resource\n");
663 		goto err_badres;
664 	}
665 
666 	rtc->regsize = res->end - res->start + 1;
667 
668 	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
669 	if (unlikely(!rtc->res)) {
670 		ret = -EBUSY;
671 		goto err_badres;
672 	}
673 
674 	rtc->regbase = ioremap_nocache(rtc->res->start, rtc->regsize);
675 	if (unlikely(!rtc->regbase)) {
676 		ret = -EINVAL;
677 		goto err_badmap;
678 	}
679 
680 	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
681 					   &sh_rtc_ops, THIS_MODULE);
682 	if (IS_ERR(rtc->rtc_dev)) {
683 		ret = PTR_ERR(rtc->rtc_dev);
684 		goto err_unmap;
685 	}
686 
687 	rtc->capabilities = RTC_DEF_CAPABILITIES;
688 	if (pdev->dev.platform_data) {
689 		struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
690 
691 		/*
692 		 * Some CPUs have special capabilities in addition to the
693 		 * default set. Add those in here.
694 		 */
695 		rtc->capabilities |= pinfo->capabilities;
696 	}
697 
698 	rtc->rtc_dev->max_user_freq = 256;
699 
700 	platform_set_drvdata(pdev, rtc);
701 
702 	if (rtc->carry_irq <= 0) {
703 		/* register shared periodic/carry/alarm irq */
704 		ret = request_irq(rtc->periodic_irq, sh_rtc_shared,
705 				  IRQF_DISABLED, "sh-rtc", rtc);
706 		if (unlikely(ret)) {
707 			dev_err(&pdev->dev,
708 				"request IRQ failed with %d, IRQ %d\n", ret,
709 				rtc->periodic_irq);
710 			goto err_unmap;
711 		}
712 	} else {
713 		/* register periodic/carry/alarm irqs */
714 		ret = request_irq(rtc->periodic_irq, sh_rtc_periodic,
715 				  IRQF_DISABLED, "sh-rtc period", rtc);
716 		if (unlikely(ret)) {
717 			dev_err(&pdev->dev,
718 				"request period IRQ failed with %d, IRQ %d\n",
719 				ret, rtc->periodic_irq);
720 			goto err_unmap;
721 		}
722 
723 		ret = request_irq(rtc->carry_irq, sh_rtc_interrupt,
724 				  IRQF_DISABLED, "sh-rtc carry", rtc);
725 		if (unlikely(ret)) {
726 			dev_err(&pdev->dev,
727 				"request carry IRQ failed with %d, IRQ %d\n",
728 				ret, rtc->carry_irq);
729 			free_irq(rtc->periodic_irq, rtc);
730 			goto err_unmap;
731 		}
732 
733 		ret = request_irq(rtc->alarm_irq, sh_rtc_alarm,
734 				  IRQF_DISABLED, "sh-rtc alarm", rtc);
735 		if (unlikely(ret)) {
736 			dev_err(&pdev->dev,
737 				"request alarm IRQ failed with %d, IRQ %d\n",
738 				ret, rtc->alarm_irq);
739 			free_irq(rtc->carry_irq, rtc);
740 			free_irq(rtc->periodic_irq, rtc);
741 			goto err_unmap;
742 		}
743 	}
744 
745 	/* everything disabled by default */
746 	rtc->periodic_freq = 0;
747 	rtc->rtc_dev->irq_freq = 0;
748 	sh_rtc_setpie(&pdev->dev, 0);
749 	sh_rtc_setaie(&pdev->dev, 0);
750 	sh_rtc_setcie(&pdev->dev, 0);
751 
752 	/* reset rtc to epoch 0 if time is invalid */
753 	if (rtc_read_time(rtc->rtc_dev, &r) < 0) {
754 		rtc_time_to_tm(0, &r);
755 		rtc_set_time(rtc->rtc_dev, &r);
756 	}
757 
758 	device_init_wakeup(&pdev->dev, 1);
759 	return 0;
760 
761 err_unmap:
762 	iounmap(rtc->regbase);
763 err_badmap:
764 	release_resource(rtc->res);
765 err_badres:
766 	kfree(rtc);
767 
768 	return ret;
769 }
770 
771 static int __devexit sh_rtc_remove(struct platform_device *pdev)
772 {
773 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
774 
775 	if (likely(rtc->rtc_dev))
776 		rtc_device_unregister(rtc->rtc_dev);
777 
778 	sh_rtc_setpie(&pdev->dev, 0);
779 	sh_rtc_setaie(&pdev->dev, 0);
780 	sh_rtc_setcie(&pdev->dev, 0);
781 
782 	free_irq(rtc->periodic_irq, rtc);
783 	if (rtc->carry_irq > 0) {
784 		free_irq(rtc->carry_irq, rtc);
785 		free_irq(rtc->alarm_irq, rtc);
786 	}
787 
788 	release_resource(rtc->res);
789 
790 	iounmap(rtc->regbase);
791 
792 	platform_set_drvdata(pdev, NULL);
793 
794 	kfree(rtc);
795 
796 	return 0;
797 }
798 
799 static void sh_rtc_set_irq_wake(struct device *dev, int enabled)
800 {
801 	struct platform_device *pdev = to_platform_device(dev);
802 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
803 
804 	set_irq_wake(rtc->periodic_irq, enabled);
805 	if (rtc->carry_irq > 0) {
806 		set_irq_wake(rtc->carry_irq, enabled);
807 		set_irq_wake(rtc->alarm_irq, enabled);
808 	}
809 
810 }
811 
812 static int sh_rtc_suspend(struct device *dev)
813 {
814 	if (device_may_wakeup(dev))
815 		sh_rtc_set_irq_wake(dev, 1);
816 
817 	return 0;
818 }
819 
820 static int sh_rtc_resume(struct device *dev)
821 {
822 	if (device_may_wakeup(dev))
823 		sh_rtc_set_irq_wake(dev, 0);
824 
825 	return 0;
826 }
827 
828 static struct dev_pm_ops sh_rtc_dev_pm_ops = {
829 	.suspend = sh_rtc_suspend,
830 	.resume = sh_rtc_resume,
831 };
832 
833 static struct platform_driver sh_rtc_platform_driver = {
834 	.driver		= {
835 		.name	= DRV_NAME,
836 		.owner	= THIS_MODULE,
837 		.pm	= &sh_rtc_dev_pm_ops,
838 	},
839 	.probe		= sh_rtc_probe,
840 	.remove		= __devexit_p(sh_rtc_remove),
841 };
842 
843 static int __init sh_rtc_init(void)
844 {
845 	return platform_driver_register(&sh_rtc_platform_driver);
846 }
847 
848 static void __exit sh_rtc_exit(void)
849 {
850 	platform_driver_unregister(&sh_rtc_platform_driver);
851 }
852 
853 module_init(sh_rtc_init);
854 module_exit(sh_rtc_exit);
855 
856 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
857 MODULE_VERSION(DRV_VERSION);
858 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
859 	      "Jamie Lenehan <lenehan@twibble.org>, "
860 	      "Angelo Castello <angelo.castello@st.com>");
861 MODULE_LICENSE("GPL");
862 MODULE_ALIAS("platform:" DRV_NAME);
863