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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/rtc/
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
91struct 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
105static 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
121static 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
136static 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
169static 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
181static 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
193static 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
205static 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
219static 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
244static 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
294static 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
313static 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
328static 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
347static 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_AIE_OFF:
354	case RTC_AIE_ON:
355		sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
356		break;
357	case RTC_UIE_OFF:
358		rtc->periodic_freq &= ~PF_OXS;
359		sh_rtc_setcie(dev, 0);
360		break;
361	case RTC_UIE_ON:
362		rtc->periodic_freq |= PF_OXS;
363		sh_rtc_setcie(dev, 1);
364		break;
365	default:
366		ret = -ENOIOCTLCMD;
367	}
368
369	return ret;
370}
371
372static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
373{
374	struct platform_device *pdev = to_platform_device(dev);
375	struct sh_rtc *rtc = platform_get_drvdata(pdev);
376	unsigned int sec128, sec2, yr, yr100, cf_bit;
377
378	do {
379		unsigned int tmp;
380
381		spin_lock_irq(&rtc->lock);
382
383		tmp = readb(rtc->regbase + RCR1);
384		tmp &= ~RCR1_CF; /* Clear CF-bit */
385		tmp |= RCR1_CIE;
386		writeb(tmp, rtc->regbase + RCR1);
387
388		sec128 = readb(rtc->regbase + R64CNT);
389
390		tm->tm_sec	= bcd2bin(readb(rtc->regbase + RSECCNT));
391		tm->tm_min	= bcd2bin(readb(rtc->regbase + RMINCNT));
392		tm->tm_hour	= bcd2bin(readb(rtc->regbase + RHRCNT));
393		tm->tm_wday	= bcd2bin(readb(rtc->regbase + RWKCNT));
394		tm->tm_mday	= bcd2bin(readb(rtc->regbase + RDAYCNT));
395		tm->tm_mon	= bcd2bin(readb(rtc->regbase + RMONCNT)) - 1;
396
397		if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
398			yr  = readw(rtc->regbase + RYRCNT);
399			yr100 = bcd2bin(yr >> 8);
400			yr &= 0xff;
401		} else {
402			yr  = readb(rtc->regbase + RYRCNT);
403			yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20);
404		}
405
406		tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900;
407
408		sec2 = readb(rtc->regbase + R64CNT);
409		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
410
411		spin_unlock_irq(&rtc->lock);
412	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
413
414#if RTC_BIT_INVERTED != 0
415	if ((sec128 & RTC_BIT_INVERTED))
416		tm->tm_sec--;
417#endif
418
419	/* only keep the carry interrupt enabled if UIE is on */
420	if (!(rtc->periodic_freq & PF_OXS))
421		sh_rtc_setcie(dev, 0);
422
423	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
424		"mday=%d, mon=%d, year=%d, wday=%d\n",
425		__func__,
426		tm->tm_sec, tm->tm_min, tm->tm_hour,
427		tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
428
429	return rtc_valid_tm(tm);
430}
431
432static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
433{
434	struct platform_device *pdev = to_platform_device(dev);
435	struct sh_rtc *rtc = platform_get_drvdata(pdev);
436	unsigned int tmp;
437	int year;
438
439	spin_lock_irq(&rtc->lock);
440
441	/* Reset pre-scaler & stop RTC */
442	tmp = readb(rtc->regbase + RCR2);
443	tmp |= RCR2_RESET;
444	tmp &= ~RCR2_START;
445	writeb(tmp, rtc->regbase + RCR2);
446
447	writeb(bin2bcd(tm->tm_sec),  rtc->regbase + RSECCNT);
448	writeb(bin2bcd(tm->tm_min),  rtc->regbase + RMINCNT);
449	writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT);
450	writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT);
451	writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT);
452	writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT);
453
454	if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
455		year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) |
456			bin2bcd(tm->tm_year % 100);
457		writew(year, rtc->regbase + RYRCNT);
458	} else {
459		year = tm->tm_year % 100;
460		writeb(bin2bcd(year), rtc->regbase + RYRCNT);
461	}
462
463	/* Start RTC */
464	tmp = readb(rtc->regbase + RCR2);
465	tmp &= ~RCR2_RESET;
466	tmp |= RCR2_RTCEN | RCR2_START;
467	writeb(tmp, rtc->regbase + RCR2);
468
469	spin_unlock_irq(&rtc->lock);
470
471	return 0;
472}
473
474static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
475{
476	unsigned int byte;
477	int value = 0xff;	/* return 0xff for ignored values */
478
479	byte = readb(rtc->regbase + reg_off);
480	if (byte & AR_ENB) {
481		byte &= ~AR_ENB;	/* strip the enable bit */
482		value = bcd2bin(byte);
483	}
484
485	return value;
486}
487
488static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
489{
490	struct platform_device *pdev = to_platform_device(dev);
491	struct sh_rtc *rtc = platform_get_drvdata(pdev);
492	struct rtc_time *tm = &wkalrm->time;
493
494	spin_lock_irq(&rtc->lock);
495
496	tm->tm_sec	= sh_rtc_read_alarm_value(rtc, RSECAR);
497	tm->tm_min	= sh_rtc_read_alarm_value(rtc, RMINAR);
498	tm->tm_hour	= sh_rtc_read_alarm_value(rtc, RHRAR);
499	tm->tm_wday	= sh_rtc_read_alarm_value(rtc, RWKAR);
500	tm->tm_mday	= sh_rtc_read_alarm_value(rtc, RDAYAR);
501	tm->tm_mon	= sh_rtc_read_alarm_value(rtc, RMONAR);
502	if (tm->tm_mon > 0)
503		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
504	tm->tm_year     = 0xffff;
505
506	wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
507
508	spin_unlock_irq(&rtc->lock);
509
510	return 0;
511}
512
513static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
514					    int value, int reg_off)
515{
516	/* < 0 for a value that is ignored */
517	if (value < 0)
518		writeb(0, rtc->regbase + reg_off);
519	else
520		writeb(bin2bcd(value) | AR_ENB,  rtc->regbase + reg_off);
521}
522
523static int sh_rtc_check_alarm(struct rtc_time *tm)
524{
525	/*
526	 * The original rtc says anything > 0xc0 is "don't care" or "match
527	 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
528	 * The original rtc doesn't support years - some things use -1 and
529	 * some 0xffff. We use -1 to make out tests easier.
530	 */
531	if (tm->tm_year == 0xffff)
532		tm->tm_year = -1;
533	if (tm->tm_mon >= 0xff)
534		tm->tm_mon = -1;
535	if (tm->tm_mday >= 0xff)
536		tm->tm_mday = -1;
537	if (tm->tm_wday >= 0xff)
538		tm->tm_wday = -1;
539	if (tm->tm_hour >= 0xff)
540		tm->tm_hour = -1;
541	if (tm->tm_min >= 0xff)
542		tm->tm_min = -1;
543	if (tm->tm_sec >= 0xff)
544		tm->tm_sec = -1;
545
546	if (tm->tm_year > 9999 ||
547		tm->tm_mon >= 12 ||
548		tm->tm_mday == 0 || tm->tm_mday >= 32 ||
549		tm->tm_wday >= 7 ||
550		tm->tm_hour >= 24 ||
551		tm->tm_min >= 60 ||
552		tm->tm_sec >= 60)
553		return -EINVAL;
554
555	return 0;
556}
557
558static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
559{
560	struct platform_device *pdev = to_platform_device(dev);
561	struct sh_rtc *rtc = platform_get_drvdata(pdev);
562	unsigned int rcr1;
563	struct rtc_time *tm = &wkalrm->time;
564	int mon, err;
565
566	err = sh_rtc_check_alarm(tm);
567	if (unlikely(err < 0))
568		return err;
569
570	spin_lock_irq(&rtc->lock);
571
572	/* disable alarm interrupt and clear the alarm flag */
573	rcr1 = readb(rtc->regbase + RCR1);
574	rcr1 &= ~(RCR1_AF | RCR1_AIE);
575	writeb(rcr1, rtc->regbase + RCR1);
576
577	/* set alarm time */
578	sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
579	sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
580	sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
581	sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
582	sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
583	mon = tm->tm_mon;
584	if (mon >= 0)
585		mon += 1;
586	sh_rtc_write_alarm_value(rtc, mon, RMONAR);
587
588	if (wkalrm->enabled) {
589		rcr1 |= RCR1_AIE;
590		writeb(rcr1, rtc->regbase + RCR1);
591	}
592
593	spin_unlock_irq(&rtc->lock);
594
595	return 0;
596}
597
598static struct rtc_class_ops sh_rtc_ops = {
599	.ioctl		= sh_rtc_ioctl,
600	.read_time	= sh_rtc_read_time,
601	.set_time	= sh_rtc_set_time,
602	.read_alarm	= sh_rtc_read_alarm,
603	.set_alarm	= sh_rtc_set_alarm,
604	.irq_set_state	= sh_rtc_irq_set_state,
605	.irq_set_freq	= sh_rtc_irq_set_freq,
606	.proc		= sh_rtc_proc,
607};
608
609static int __init sh_rtc_probe(struct platform_device *pdev)
610{
611	struct sh_rtc *rtc;
612	struct resource *res;
613	struct rtc_time r;
614	char clk_name[6];
615	int clk_id, ret;
616
617	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
618	if (unlikely(!rtc))
619		return -ENOMEM;
620
621	spin_lock_init(&rtc->lock);
622
623	/* get periodic/carry/alarm irqs */
624	ret = platform_get_irq(pdev, 0);
625	if (unlikely(ret <= 0)) {
626		ret = -ENOENT;
627		dev_err(&pdev->dev, "No IRQ resource\n");
628		goto err_badres;
629	}
630
631	rtc->periodic_irq = ret;
632	rtc->carry_irq = platform_get_irq(pdev, 1);
633	rtc->alarm_irq = platform_get_irq(pdev, 2);
634
635	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
636	if (unlikely(res == NULL)) {
637		ret = -ENOENT;
638		dev_err(&pdev->dev, "No IO resource\n");
639		goto err_badres;
640	}
641
642	rtc->regsize = resource_size(res);
643
644	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
645	if (unlikely(!rtc->res)) {
646		ret = -EBUSY;
647		goto err_badres;
648	}
649
650	rtc->regbase = ioremap_nocache(rtc->res->start, rtc->regsize);
651	if (unlikely(!rtc->regbase)) {
652		ret = -EINVAL;
653		goto err_badmap;
654	}
655
656	clk_id = pdev->id;
657	/* With a single device, the clock id is still "rtc0" */
658	if (clk_id < 0)
659		clk_id = 0;
660
661	snprintf(clk_name, sizeof(clk_name), "rtc%d", clk_id);
662
663	rtc->clk = clk_get(&pdev->dev, clk_name);
664	if (IS_ERR(rtc->clk)) {
665		/*
666		 * No error handling for rtc->clk intentionally, not all
667		 * platforms will have a unique clock for the RTC, and
668		 * the clk API can handle the struct clk pointer being
669		 * NULL.
670		 */
671		rtc->clk = NULL;
672	}
673
674	clk_enable(rtc->clk);
675
676	rtc->capabilities = RTC_DEF_CAPABILITIES;
677	if (pdev->dev.platform_data) {
678		struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
679
680		/*
681		 * Some CPUs have special capabilities in addition to the
682		 * default set. Add those in here.
683		 */
684		rtc->capabilities |= pinfo->capabilities;
685	}
686
687	if (rtc->carry_irq <= 0) {
688		/* register shared periodic/carry/alarm irq */
689		ret = request_irq(rtc->periodic_irq, sh_rtc_shared,
690				  IRQF_DISABLED, "sh-rtc", rtc);
691		if (unlikely(ret)) {
692			dev_err(&pdev->dev,
693				"request IRQ failed with %d, IRQ %d\n", ret,
694				rtc->periodic_irq);
695			goto err_unmap;
696		}
697	} else {
698		/* register periodic/carry/alarm irqs */
699		ret = request_irq(rtc->periodic_irq, sh_rtc_periodic,
700				  IRQF_DISABLED, "sh-rtc period", rtc);
701		if (unlikely(ret)) {
702			dev_err(&pdev->dev,
703				"request period IRQ failed with %d, IRQ %d\n",
704				ret, rtc->periodic_irq);
705			goto err_unmap;
706		}
707
708		ret = request_irq(rtc->carry_irq, sh_rtc_interrupt,
709				  IRQF_DISABLED, "sh-rtc carry", rtc);
710		if (unlikely(ret)) {
711			dev_err(&pdev->dev,
712				"request carry IRQ failed with %d, IRQ %d\n",
713				ret, rtc->carry_irq);
714			free_irq(rtc->periodic_irq, rtc);
715			goto err_unmap;
716		}
717
718		ret = request_irq(rtc->alarm_irq, sh_rtc_alarm,
719				  IRQF_DISABLED, "sh-rtc alarm", rtc);
720		if (unlikely(ret)) {
721			dev_err(&pdev->dev,
722				"request alarm IRQ failed with %d, IRQ %d\n",
723				ret, rtc->alarm_irq);
724			free_irq(rtc->carry_irq, rtc);
725			free_irq(rtc->periodic_irq, rtc);
726			goto err_unmap;
727		}
728	}
729
730	platform_set_drvdata(pdev, rtc);
731
732	/* everything disabled by default */
733	sh_rtc_irq_set_freq(&pdev->dev, 0);
734	sh_rtc_irq_set_state(&pdev->dev, 0);
735	sh_rtc_setaie(&pdev->dev, 0);
736	sh_rtc_setcie(&pdev->dev, 0);
737
738	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
739					   &sh_rtc_ops, THIS_MODULE);
740	if (IS_ERR(rtc->rtc_dev)) {
741		ret = PTR_ERR(rtc->rtc_dev);
742		free_irq(rtc->periodic_irq, rtc);
743		free_irq(rtc->carry_irq, rtc);
744		free_irq(rtc->alarm_irq, rtc);
745		goto err_unmap;
746	}
747
748	rtc->rtc_dev->max_user_freq = 256;
749
750	/* reset rtc to epoch 0 if time is invalid */
751	if (rtc_read_time(rtc->rtc_dev, &r) < 0) {
752		rtc_time_to_tm(0, &r);
753		rtc_set_time(rtc->rtc_dev, &r);
754	}
755
756	device_init_wakeup(&pdev->dev, 1);
757	return 0;
758
759err_unmap:
760	clk_disable(rtc->clk);
761	clk_put(rtc->clk);
762	iounmap(rtc->regbase);
763err_badmap:
764	release_resource(rtc->res);
765err_badres:
766	kfree(rtc);
767
768	return ret;
769}
770
771static int __exit sh_rtc_remove(struct platform_device *pdev)
772{
773	struct sh_rtc *rtc = platform_get_drvdata(pdev);
774
775	rtc_device_unregister(rtc->rtc_dev);
776	sh_rtc_irq_set_state(&pdev->dev, 0);
777
778	sh_rtc_setaie(&pdev->dev, 0);
779	sh_rtc_setcie(&pdev->dev, 0);
780
781	free_irq(rtc->periodic_irq, rtc);
782
783	if (rtc->carry_irq > 0) {
784		free_irq(rtc->carry_irq, rtc);
785		free_irq(rtc->alarm_irq, rtc);
786	}
787
788	iounmap(rtc->regbase);
789	release_resource(rtc->res);
790
791	clk_disable(rtc->clk);
792	clk_put(rtc->clk);
793
794	platform_set_drvdata(pdev, NULL);
795
796	kfree(rtc);
797
798	return 0;
799}
800
801static void sh_rtc_set_irq_wake(struct device *dev, int enabled)
802{
803	struct platform_device *pdev = to_platform_device(dev);
804	struct sh_rtc *rtc = platform_get_drvdata(pdev);
805
806	set_irq_wake(rtc->periodic_irq, enabled);
807
808	if (rtc->carry_irq > 0) {
809		set_irq_wake(rtc->carry_irq, enabled);
810		set_irq_wake(rtc->alarm_irq, enabled);
811	}
812}
813
814static int sh_rtc_suspend(struct device *dev)
815{
816	if (device_may_wakeup(dev))
817		sh_rtc_set_irq_wake(dev, 1);
818
819	return 0;
820}
821
822static int sh_rtc_resume(struct device *dev)
823{
824	if (device_may_wakeup(dev))
825		sh_rtc_set_irq_wake(dev, 0);
826
827	return 0;
828}
829
830static const struct dev_pm_ops sh_rtc_dev_pm_ops = {
831	.suspend = sh_rtc_suspend,
832	.resume = sh_rtc_resume,
833};
834
835static struct platform_driver sh_rtc_platform_driver = {
836	.driver		= {
837		.name	= DRV_NAME,
838		.owner	= THIS_MODULE,
839		.pm	= &sh_rtc_dev_pm_ops,
840	},
841	.remove		= __exit_p(sh_rtc_remove),
842};
843
844static int __init sh_rtc_init(void)
845{
846	return platform_driver_probe(&sh_rtc_platform_driver, sh_rtc_probe);
847}
848
849static void __exit sh_rtc_exit(void)
850{
851	platform_driver_unregister(&sh_rtc_platform_driver);
852}
853
854module_init(sh_rtc_init);
855module_exit(sh_rtc_exit);
856
857MODULE_DESCRIPTION("SuperH on-chip RTC driver");
858MODULE_VERSION(DRV_VERSION);
859MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, "
860	      "Jamie Lenehan <lenehan@twibble.org>, "
861	      "Angelo Castello <angelo.castello@st.com>");
862MODULE_LICENSE("GPL");
863MODULE_ALIAS("platform:" DRV_NAME);
864