xref: /openbmc/linux/drivers/rtc/rtc-sh.c (revision 64c70b1c)
1 /*
2  * SuperH On-Chip RTC Support
3  *
4  * Copyright (C) 2006  Paul Mundt
5  * Copyright (C) 2006  Jamie Lenehan
6  *
7  * Based on the old arch/sh/kernel/cpu/rtc.c by:
8  *
9  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
10  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
11  *
12  * This file is subject to the terms and conditions of the GNU General Public
13  * License.  See the file "COPYING" in the main directory of this archive
14  * for more details.
15  */
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/bcd.h>
19 #include <linux/rtc.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/seq_file.h>
23 #include <linux/interrupt.h>
24 #include <linux/spinlock.h>
25 #include <linux/io.h>
26 
27 #define DRV_NAME	"sh-rtc"
28 #define DRV_VERSION	"0.1.2"
29 
30 #ifdef CONFIG_CPU_SH3
31 #define rtc_reg_size		sizeof(u16)
32 #define RTC_BIT_INVERTED	0	/* No bug on SH7708, SH7709A */
33 #elif defined(CONFIG_CPU_SH4)
34 #define rtc_reg_size		sizeof(u32)
35 #define RTC_BIT_INVERTED	0x40	/* bug on SH7750, SH7750S */
36 #endif
37 
38 #define RTC_REG(r)	((r) * rtc_reg_size)
39 
40 #define R64CNT		RTC_REG(0)
41 
42 #define RSECCNT		RTC_REG(1)	/* RTC sec */
43 #define RMINCNT		RTC_REG(2)	/* RTC min */
44 #define RHRCNT		RTC_REG(3)	/* RTC hour */
45 #define RWKCNT		RTC_REG(4)	/* RTC week */
46 #define RDAYCNT		RTC_REG(5)	/* RTC day */
47 #define RMONCNT		RTC_REG(6)	/* RTC month */
48 #define RYRCNT		RTC_REG(7)	/* RTC year */
49 #define RSECAR		RTC_REG(8)	/* ALARM sec */
50 #define RMINAR		RTC_REG(9)	/* ALARM min */
51 #define RHRAR		RTC_REG(10)	/* ALARM hour */
52 #define RWKAR		RTC_REG(11)	/* ALARM week */
53 #define RDAYAR		RTC_REG(12)	/* ALARM day */
54 #define RMONAR		RTC_REG(13)	/* ALARM month */
55 #define RCR1		RTC_REG(14)	/* Control */
56 #define RCR2		RTC_REG(15)	/* Control */
57 
58 /* ALARM Bits - or with BCD encoded value */
59 #define AR_ENB		0x80	/* Enable for alarm cmp   */
60 
61 /* RCR1 Bits */
62 #define RCR1_CF		0x80	/* Carry Flag             */
63 #define RCR1_CIE	0x10	/* Carry Interrupt Enable */
64 #define RCR1_AIE	0x08	/* Alarm Interrupt Enable */
65 #define RCR1_AF		0x01	/* Alarm Flag             */
66 
67 /* RCR2 Bits */
68 #define RCR2_PEF	0x80	/* PEriodic interrupt Flag */
69 #define RCR2_PESMASK	0x70	/* Periodic interrupt Set  */
70 #define RCR2_RTCEN	0x08	/* ENable RTC              */
71 #define RCR2_ADJ	0x04	/* ADJustment (30-second)  */
72 #define RCR2_RESET	0x02	/* Reset bit               */
73 #define RCR2_START	0x01	/* Start bit               */
74 
75 struct sh_rtc {
76 	void __iomem *regbase;
77 	unsigned long regsize;
78 	struct resource *res;
79 	unsigned int alarm_irq, periodic_irq, carry_irq;
80 	struct rtc_device *rtc_dev;
81 	spinlock_t lock;
82 	int rearm_aie;
83 };
84 
85 static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
86 {
87 	struct platform_device *pdev = to_platform_device(dev_id);
88 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
89 	unsigned int tmp, events = 0;
90 
91 	spin_lock(&rtc->lock);
92 
93 	tmp = readb(rtc->regbase + RCR1);
94 	tmp &= ~RCR1_CF;
95 
96 	if (rtc->rearm_aie) {
97 		if (tmp & RCR1_AF)
98 			tmp &= ~RCR1_AF;	/* try to clear AF again */
99 		else {
100 			tmp |= RCR1_AIE;	/* AF has cleared, rearm IRQ */
101 			rtc->rearm_aie = 0;
102 		}
103 	}
104 
105 	writeb(tmp, rtc->regbase + RCR1);
106 
107 	rtc_update_irq(rtc->rtc_dev, 1, events);
108 
109 	spin_unlock(&rtc->lock);
110 
111 	return IRQ_HANDLED;
112 }
113 
114 static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
115 {
116 	struct platform_device *pdev = to_platform_device(dev_id);
117 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
118 	unsigned int tmp, events = 0;
119 
120 	spin_lock(&rtc->lock);
121 
122 	tmp = readb(rtc->regbase + RCR1);
123 
124 	/*
125 	 * If AF is set then the alarm has triggered. If we clear AF while
126 	 * the alarm time still matches the RTC time then AF will
127 	 * immediately be set again, and if AIE is enabled then the alarm
128 	 * interrupt will immediately be retrigger. So we clear AIE here
129 	 * and use rtc->rearm_aie so that the carry interrupt will keep
130 	 * trying to clear AF and once it stays cleared it'll re-enable
131 	 * AIE.
132 	 */
133 	if (tmp & RCR1_AF) {
134 		events |= RTC_AF | RTC_IRQF;
135 
136 		tmp &= ~(RCR1_AF|RCR1_AIE);
137 
138 		writeb(tmp, rtc->regbase + RCR1);
139 
140 		rtc->rearm_aie = 1;
141 
142 		rtc_update_irq(rtc->rtc_dev, 1, events);
143 	}
144 
145 	spin_unlock(&rtc->lock);
146 	return IRQ_HANDLED;
147 }
148 
149 static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
150 {
151 	struct platform_device *pdev = to_platform_device(dev_id);
152 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
153 
154 	spin_lock(&rtc->lock);
155 
156 	rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
157 
158 	spin_unlock(&rtc->lock);
159 
160 	return IRQ_HANDLED;
161 }
162 
163 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
164 {
165 	struct sh_rtc *rtc = dev_get_drvdata(dev);
166 	unsigned int tmp;
167 
168 	spin_lock_irq(&rtc->lock);
169 
170 	tmp = readb(rtc->regbase + RCR2);
171 
172 	if (enable) {
173 		tmp &= ~RCR2_PESMASK;
174 		tmp |= RCR2_PEF | (2 << 4);
175 	} else
176 		tmp &= ~(RCR2_PESMASK | RCR2_PEF);
177 
178 	writeb(tmp, rtc->regbase + RCR2);
179 
180 	spin_unlock_irq(&rtc->lock);
181 }
182 
183 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
184 {
185 	struct sh_rtc *rtc = dev_get_drvdata(dev);
186 	unsigned int tmp;
187 
188 	spin_lock_irq(&rtc->lock);
189 
190 	tmp = readb(rtc->regbase + RCR1);
191 
192 	if (!enable) {
193 		tmp &= ~RCR1_AIE;
194 		rtc->rearm_aie = 0;
195 	} else if (rtc->rearm_aie == 0)
196 		tmp |= RCR1_AIE;
197 
198 	writeb(tmp, rtc->regbase + RCR1);
199 
200 	spin_unlock_irq(&rtc->lock);
201 }
202 
203 static int sh_rtc_open(struct device *dev)
204 {
205 	struct sh_rtc *rtc = dev_get_drvdata(dev);
206 	unsigned int tmp;
207 	int ret;
208 
209 	tmp = readb(rtc->regbase + RCR1);
210 	tmp &= ~RCR1_CF;
211 	tmp |= RCR1_CIE;
212 	writeb(tmp, rtc->regbase + RCR1);
213 
214 	ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED,
215 			  "sh-rtc period", dev);
216 	if (unlikely(ret)) {
217 		dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
218 			ret, rtc->periodic_irq);
219 		return ret;
220 	}
221 
222 	ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED,
223 			  "sh-rtc carry", dev);
224 	if (unlikely(ret)) {
225 		dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
226 			ret, rtc->carry_irq);
227 		free_irq(rtc->periodic_irq, dev);
228 		goto err_bad_carry;
229 	}
230 
231 	ret = request_irq(rtc->alarm_irq, sh_rtc_alarm, IRQF_DISABLED,
232 			  "sh-rtc alarm", dev);
233 	if (unlikely(ret)) {
234 		dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
235 			ret, rtc->alarm_irq);
236 		goto err_bad_alarm;
237 	}
238 
239 	return 0;
240 
241 err_bad_alarm:
242 	free_irq(rtc->carry_irq, dev);
243 err_bad_carry:
244 	free_irq(rtc->periodic_irq, dev);
245 
246 	return ret;
247 }
248 
249 static void sh_rtc_release(struct device *dev)
250 {
251 	struct sh_rtc *rtc = dev_get_drvdata(dev);
252 
253 	sh_rtc_setpie(dev, 0);
254 	sh_rtc_setaie(dev, 0);
255 
256 	free_irq(rtc->periodic_irq, dev);
257 	free_irq(rtc->carry_irq, dev);
258 	free_irq(rtc->alarm_irq, dev);
259 }
260 
261 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
262 {
263 	struct sh_rtc *rtc = dev_get_drvdata(dev);
264 	unsigned int tmp;
265 
266 	tmp = readb(rtc->regbase + RCR1);
267 	seq_printf(seq, "carry_IRQ\t: %s\n",
268 		   (tmp & RCR1_CIE) ? "yes" : "no");
269 
270 	tmp = readb(rtc->regbase + RCR2);
271 	seq_printf(seq, "periodic_IRQ\t: %s\n",
272 		   (tmp & RCR2_PEF) ? "yes" : "no");
273 
274 	return 0;
275 }
276 
277 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
278 {
279 	unsigned int ret = -ENOIOCTLCMD;
280 
281 	switch (cmd) {
282 	case RTC_PIE_OFF:
283 	case RTC_PIE_ON:
284 		sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
285 		ret = 0;
286 		break;
287 	case RTC_AIE_OFF:
288 	case RTC_AIE_ON:
289 		sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
290 		ret = 0;
291 		break;
292 	}
293 
294 	return ret;
295 }
296 
297 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
298 {
299 	struct platform_device *pdev = to_platform_device(dev);
300 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
301 	unsigned int sec128, sec2, yr, yr100, cf_bit;
302 
303 	do {
304 		unsigned int tmp;
305 
306 		spin_lock_irq(&rtc->lock);
307 
308 		tmp = readb(rtc->regbase + RCR1);
309 		tmp &= ~RCR1_CF; /* Clear CF-bit */
310 		tmp |= RCR1_CIE;
311 		writeb(tmp, rtc->regbase + RCR1);
312 
313 		sec128 = readb(rtc->regbase + R64CNT);
314 
315 		tm->tm_sec	= BCD2BIN(readb(rtc->regbase + RSECCNT));
316 		tm->tm_min	= BCD2BIN(readb(rtc->regbase + RMINCNT));
317 		tm->tm_hour	= BCD2BIN(readb(rtc->regbase + RHRCNT));
318 		tm->tm_wday	= BCD2BIN(readb(rtc->regbase + RWKCNT));
319 		tm->tm_mday	= BCD2BIN(readb(rtc->regbase + RDAYCNT));
320 		tm->tm_mon	= BCD2BIN(readb(rtc->regbase + RMONCNT)) - 1;
321 
322 #if defined(CONFIG_CPU_SH4)
323 		yr  = readw(rtc->regbase + RYRCNT);
324 		yr100 = BCD2BIN(yr >> 8);
325 		yr &= 0xff;
326 #else
327 		yr  = readb(rtc->regbase + RYRCNT);
328 		yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
329 #endif
330 
331 		tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
332 
333 		sec2 = readb(rtc->regbase + R64CNT);
334 		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
335 
336 		spin_unlock_irq(&rtc->lock);
337 	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
338 
339 #if RTC_BIT_INVERTED != 0
340 	if ((sec128 & RTC_BIT_INVERTED))
341 		tm->tm_sec--;
342 #endif
343 
344 	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
345 		"mday=%d, mon=%d, year=%d, wday=%d\n",
346 		__FUNCTION__,
347 		tm->tm_sec, tm->tm_min, tm->tm_hour,
348 		tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
349 
350 	if (rtc_valid_tm(tm) < 0)
351 		dev_err(dev, "invalid date\n");
352 
353 	return 0;
354 }
355 
356 static int sh_rtc_set_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 tmp;
361 	int year;
362 
363 	spin_lock_irq(&rtc->lock);
364 
365 	/* Reset pre-scaler & stop RTC */
366 	tmp = readb(rtc->regbase + RCR2);
367 	tmp |= RCR2_RESET;
368 	writeb(tmp, rtc->regbase + RCR2);
369 
370 	writeb(BIN2BCD(tm->tm_sec),  rtc->regbase + RSECCNT);
371 	writeb(BIN2BCD(tm->tm_min),  rtc->regbase + RMINCNT);
372 	writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
373 	writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
374 	writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
375 	writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT);
376 
377 #ifdef CONFIG_CPU_SH3
378 	year = tm->tm_year % 100;
379 	writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
380 #else
381 	year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
382 		BIN2BCD(tm->tm_year % 100);
383 	writew(year, rtc->regbase + RYRCNT);
384 #endif
385 
386 	/* Start RTC */
387 	tmp = readb(rtc->regbase + RCR2);
388 	tmp &= ~RCR2_RESET;
389 	tmp |= RCR2_RTCEN | RCR2_START;
390 	writeb(tmp, rtc->regbase + RCR2);
391 
392 	spin_unlock_irq(&rtc->lock);
393 
394 	return 0;
395 }
396 
397 static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
398 {
399 	unsigned int byte;
400 	int value = 0xff;	/* return 0xff for ignored values */
401 
402 	byte = readb(rtc->regbase + reg_off);
403 	if (byte & AR_ENB) {
404 		byte &= ~AR_ENB;	/* strip the enable bit */
405 		value = BCD2BIN(byte);
406 	}
407 
408 	return value;
409 }
410 
411 static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
412 {
413 	struct platform_device *pdev = to_platform_device(dev);
414 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
415 	struct rtc_time* tm = &wkalrm->time;
416 
417 	spin_lock_irq(&rtc->lock);
418 
419 	tm->tm_sec	= sh_rtc_read_alarm_value(rtc, RSECAR);
420 	tm->tm_min	= sh_rtc_read_alarm_value(rtc, RMINAR);
421 	tm->tm_hour	= sh_rtc_read_alarm_value(rtc, RHRAR);
422 	tm->tm_wday	= sh_rtc_read_alarm_value(rtc, RWKAR);
423 	tm->tm_mday	= sh_rtc_read_alarm_value(rtc, RDAYAR);
424 	tm->tm_mon	= sh_rtc_read_alarm_value(rtc, RMONAR);
425 	if (tm->tm_mon > 0)
426 		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
427 	tm->tm_year     = 0xffff;
428 
429 	wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
430 
431 	spin_unlock_irq(&rtc->lock);
432 
433 	return 0;
434 }
435 
436 static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
437 					    int value, int reg_off)
438 {
439 	/* < 0 for a value that is ignored */
440 	if (value < 0)
441 		writeb(0, rtc->regbase + reg_off);
442 	else
443 		writeb(BIN2BCD(value) | AR_ENB,  rtc->regbase + reg_off);
444 }
445 
446 static int sh_rtc_check_alarm(struct rtc_time* tm)
447 {
448 	/*
449 	 * The original rtc says anything > 0xc0 is "don't care" or "match
450 	 * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
451 	 * The original rtc doesn't support years - some things use -1 and
452 	 * some 0xffff. We use -1 to make out tests easier.
453 	 */
454 	if (tm->tm_year == 0xffff)
455 		tm->tm_year = -1;
456 	if (tm->tm_mon >= 0xff)
457 		tm->tm_mon = -1;
458 	if (tm->tm_mday >= 0xff)
459 		tm->tm_mday = -1;
460 	if (tm->tm_wday >= 0xff)
461 		tm->tm_wday = -1;
462 	if (tm->tm_hour >= 0xff)
463 		tm->tm_hour = -1;
464 	if (tm->tm_min >= 0xff)
465 		tm->tm_min = -1;
466 	if (tm->tm_sec >= 0xff)
467 		tm->tm_sec = -1;
468 
469 	if (tm->tm_year > 9999 ||
470 		tm->tm_mon >= 12 ||
471 		tm->tm_mday == 0 || tm->tm_mday >= 32 ||
472 		tm->tm_wday >= 7 ||
473 		tm->tm_hour >= 24 ||
474 		tm->tm_min >= 60 ||
475 		tm->tm_sec >= 60)
476 		return -EINVAL;
477 
478 	return 0;
479 }
480 
481 static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
482 {
483 	struct platform_device *pdev = to_platform_device(dev);
484 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
485 	unsigned int rcr1;
486 	struct rtc_time *tm = &wkalrm->time;
487 	int mon, err;
488 
489 	err = sh_rtc_check_alarm(tm);
490 	if (unlikely(err < 0))
491 		return err;
492 
493 	spin_lock_irq(&rtc->lock);
494 
495 	/* disable alarm interrupt and clear the alarm flag */
496 	rcr1 = readb(rtc->regbase + RCR1);
497 	rcr1 &= ~(RCR1_AF|RCR1_AIE);
498 	writeb(rcr1, rtc->regbase + RCR1);
499 
500 	rtc->rearm_aie = 0;
501 
502 	/* set alarm time */
503 	sh_rtc_write_alarm_value(rtc, tm->tm_sec,  RSECAR);
504 	sh_rtc_write_alarm_value(rtc, tm->tm_min,  RMINAR);
505 	sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
506 	sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
507 	sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
508 	mon = tm->tm_mon;
509 	if (mon >= 0)
510 		mon += 1;
511 	sh_rtc_write_alarm_value(rtc, mon, RMONAR);
512 
513 	if (wkalrm->enabled) {
514 		rcr1 |= RCR1_AIE;
515 		writeb(rcr1, rtc->regbase + RCR1);
516 	}
517 
518 	spin_unlock_irq(&rtc->lock);
519 
520 	return 0;
521 }
522 
523 static struct rtc_class_ops sh_rtc_ops = {
524 	.open		= sh_rtc_open,
525 	.release	= sh_rtc_release,
526 	.ioctl		= sh_rtc_ioctl,
527 	.read_time	= sh_rtc_read_time,
528 	.set_time	= sh_rtc_set_time,
529 	.read_alarm	= sh_rtc_read_alarm,
530 	.set_alarm	= sh_rtc_set_alarm,
531 	.proc		= sh_rtc_proc,
532 };
533 
534 static int __devinit sh_rtc_probe(struct platform_device *pdev)
535 {
536 	struct sh_rtc *rtc;
537 	struct resource *res;
538 	int ret = -ENOENT;
539 
540 	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
541 	if (unlikely(!rtc))
542 		return -ENOMEM;
543 
544 	spin_lock_init(&rtc->lock);
545 
546 	rtc->periodic_irq = platform_get_irq(pdev, 0);
547 	if (unlikely(rtc->periodic_irq < 0)) {
548 		dev_err(&pdev->dev, "No IRQ for period\n");
549 		goto err_badres;
550 	}
551 
552 	rtc->carry_irq = platform_get_irq(pdev, 1);
553 	if (unlikely(rtc->carry_irq < 0)) {
554 		dev_err(&pdev->dev, "No IRQ for carry\n");
555 		goto err_badres;
556 	}
557 
558 	rtc->alarm_irq = platform_get_irq(pdev, 2);
559 	if (unlikely(rtc->alarm_irq < 0)) {
560 		dev_err(&pdev->dev, "No IRQ for alarm\n");
561 		goto err_badres;
562 	}
563 
564 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
565 	if (unlikely(res == NULL)) {
566 		dev_err(&pdev->dev, "No IO resource\n");
567 		goto err_badres;
568 	}
569 
570 	rtc->regsize = res->end - res->start + 1;
571 
572 	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
573 	if (unlikely(!rtc->res)) {
574 		ret = -EBUSY;
575 		goto err_badres;
576 	}
577 
578 	rtc->regbase = (void __iomem *)rtc->res->start;
579 	if (unlikely(!rtc->regbase)) {
580 		ret = -EINVAL;
581 		goto err_badmap;
582 	}
583 
584 	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
585 					   &sh_rtc_ops, THIS_MODULE);
586 	if (IS_ERR(rtc)) {
587 		ret = PTR_ERR(rtc->rtc_dev);
588 		goto err_badmap;
589 	}
590 
591 	platform_set_drvdata(pdev, rtc);
592 
593 	return 0;
594 
595 err_badmap:
596 	release_resource(rtc->res);
597 err_badres:
598 	kfree(rtc);
599 
600 	return ret;
601 }
602 
603 static int __devexit sh_rtc_remove(struct platform_device *pdev)
604 {
605 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
606 
607 	if (likely(rtc->rtc_dev))
608 		rtc_device_unregister(rtc->rtc_dev);
609 
610 	sh_rtc_setpie(&pdev->dev, 0);
611 	sh_rtc_setaie(&pdev->dev, 0);
612 
613 	release_resource(rtc->res);
614 
615 	platform_set_drvdata(pdev, NULL);
616 
617 	kfree(rtc);
618 
619 	return 0;
620 }
621 static struct platform_driver sh_rtc_platform_driver = {
622 	.driver		= {
623 		.name	= DRV_NAME,
624 		.owner	= THIS_MODULE,
625 	},
626 	.probe		= sh_rtc_probe,
627 	.remove		= __devexit_p(sh_rtc_remove),
628 };
629 
630 static int __init sh_rtc_init(void)
631 {
632 	return platform_driver_register(&sh_rtc_platform_driver);
633 }
634 
635 static void __exit sh_rtc_exit(void)
636 {
637 	platform_driver_unregister(&sh_rtc_platform_driver);
638 }
639 
640 module_init(sh_rtc_init);
641 module_exit(sh_rtc_exit);
642 
643 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
644 MODULE_VERSION(DRV_VERSION);
645 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
646 MODULE_LICENSE("GPL");
647