[linux.git] / drivers / rtc / rtc-nuc900.c

/*
 * Copyright (c) 2008-2009 Nuvoton technology corporation.
 *
 * Wan ZongShun <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation;version 2 of the License.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/rtc.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/bcd.h>

/* RTC Control Registers */
#define REG_RTC_INIR		0x00
#define REG_RTC_AER		0x04
#define REG_RTC_FCR		0x08
#define REG_RTC_TLR		0x0C
#define REG_RTC_CLR		0x10
#define REG_RTC_TSSR		0x14
#define REG_RTC_DWR		0x18
#define REG_RTC_TAR		0x1C
#define REG_RTC_CAR		0x20
#define REG_RTC_LIR		0x24
#define REG_RTC_RIER		0x28
#define REG_RTC_RIIR		0x2C
#define REG_RTC_TTR		0x30

#define RTCSET			0x01
#define AERRWENB		0x10000
#define INIRRESET		0xa5eb1357
#define AERPOWERON		0xA965
#define AERPOWEROFF		0x0000
#define LEAPYEAR		0x0001
#define TICKENB			0x80
#define TICKINTENB		0x0002
#define ALARMINTENB		0x0001
#define MODE24			0x0001

struct nuc900_rtc {
	int			irq_num;
	void __iomem		*rtc_reg;
	struct rtc_device	*rtcdev;
};

struct nuc900_bcd_time {
	int bcd_sec;
	int bcd_min;
	int bcd_hour;
	int bcd_mday;
	int bcd_mon;
	int bcd_year;
};

static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
{
	struct nuc900_rtc *rtc = _rtc;
	unsigned long events = 0, rtc_irq;

	rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);

	if (rtc_irq & ALARMINTENB) {
		rtc_irq &= ~ALARMINTENB;
		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
		events |= RTC_AF | RTC_IRQF;
	}

	if (rtc_irq & TICKINTENB) {
		rtc_irq &= ~TICKINTENB;
		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
		events |= RTC_UF | RTC_IRQF;
	}

	rtc_update_irq(rtc->rtcdev, 1, events);

	return IRQ_HANDLED;
}

static int *check_rtc_access_enable(struct nuc900_rtc *nuc900_rtc)
{
	unsigned int timeout = 0x1000;
	__raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);

	mdelay(10);

	__raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);

	while (!(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
								&& timeout--)
		mdelay(1);

	if (!timeout)
		return ERR_PTR(-EPERM);

	return 0;
}

static int nuc900_rtc_bcd2bin(unsigned int timereg,
				unsigned int calreg, struct rtc_time *tm)
{
	tm->tm_mday	= bcd2bin(calreg >> 0);
	tm->tm_mon	= bcd2bin(calreg >> 8);
	tm->tm_year	= bcd2bin(calreg >> 16) + 100;

	tm->tm_sec	= bcd2bin(timereg >> 0);
	tm->tm_min	= bcd2bin(timereg >> 8);
	tm->tm_hour	= bcd2bin(timereg >> 16);

	return rtc_valid_tm(tm);
}

static void nuc900_rtc_bin2bcd(struct device *dev, struct rtc_time *settm,
						struct nuc900_bcd_time *gettm)
{
	gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
	gettm->bcd_mon  = bin2bcd(settm->tm_mon) << 8;

	if (settm->tm_year < 100) {
		dev_warn(dev, "The year will be between 1970-1999, right?\n");
		gettm->bcd_year = bin2bcd(settm->tm_year) << 16;
	} else {
		gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
	}

	gettm->bcd_sec  = bin2bcd(settm->tm_sec) << 0;
	gettm->bcd_min  = bin2bcd(settm->tm_min) << 8;
	gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
}

static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct nuc900_rtc *rtc = dev_get_drvdata(dev);

	if (enabled)
		__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
				(ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
	else
		__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
				(~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);

	return 0;
}

static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	unsigned int timeval, clrval;

	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
	clrval	= __raw_readl(rtc->rtc_reg + REG_RTC_CLR);

	return nuc900_rtc_bcd2bin(timeval, clrval, tm);
}

static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	struct nuc900_bcd_time gettm;
	unsigned long val;
	int *err;

	nuc900_rtc_bin2bcd(dev, tm, &gettm);

	err = check_rtc_access_enable(rtc);
	if (IS_ERR(err))
		return PTR_ERR(err);

	val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
	__raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);

	val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
	__raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);

	return 0;
}

static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	unsigned int timeval, carval;

	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
	carval	= __raw_readl(rtc->rtc_reg + REG_RTC_CAR);

	return nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
}

static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	struct nuc900_bcd_time tm;
	unsigned long val;
	int *err;

	nuc900_rtc_bin2bcd(dev, &alrm->time, &tm);

	err = check_rtc_access_enable(rtc);
	if (IS_ERR(err))
		return PTR_ERR(err);

	val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
	__raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);

	val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
	__raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);

	return 0;
}

static struct rtc_class_ops nuc900_rtc_ops = {
	.read_time = nuc900_rtc_read_time,
	.set_time = nuc900_rtc_set_time,
	.read_alarm = nuc900_rtc_read_alarm,
	.set_alarm = nuc900_rtc_set_alarm,
	.alarm_irq_enable = nuc900_alarm_irq_enable,
};

static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct nuc900_rtc *nuc900_rtc;
	int err = 0;

	nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
	if (!nuc900_rtc) {
		dev_err(&pdev->dev, "kzalloc nuc900_rtc failed\n");
		return -ENOMEM;
	}
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "platform_get_resource failed\n");
		err = -ENXIO;
		goto fail1;
	}

	if (!request_mem_region(res->start, resource_size(res),
				pdev->name)) {
		dev_err(&pdev->dev, "request_mem_region failed\n");
		err = -EBUSY;
		goto fail1;
	}

	nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
	if (!nuc900_rtc->rtc_reg) {
		dev_err(&pdev->dev, "ioremap rtc_reg failed\n");
		err = -ENOMEM;
		goto fail2;
	}

	platform_set_drvdata(pdev, nuc900_rtc);

	nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
						&nuc900_rtc_ops, THIS_MODULE);
	if (IS_ERR(nuc900_rtc->rtcdev)) {
		dev_err(&pdev->dev, "rtc device register failed\n");
		err = PTR_ERR(nuc900_rtc->rtcdev);
		goto fail3;
	}

	__raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
					nuc900_rtc->rtc_reg + REG_RTC_TSSR);

	nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
	if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
				0, "nuc900rtc", nuc900_rtc)) {
		dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
		err = -EBUSY;
		goto fail4;
	}

	return 0;

fail4:	rtc_device_unregister(nuc900_rtc->rtcdev);
fail3:	iounmap(nuc900_rtc->rtc_reg);
fail2:	release_mem_region(res->start, resource_size(res));
fail1:	kfree(nuc900_rtc);
	return err;
}

static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
{
	struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
	struct resource *res;

	free_irq(nuc900_rtc->irq_num, nuc900_rtc);
	rtc_device_unregister(nuc900_rtc->rtcdev);
	iounmap(nuc900_rtc->rtc_reg);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(res->start, resource_size(res));

	kfree(nuc900_rtc);

	platform_set_drvdata(pdev, NULL);

	return 0;
}

static struct platform_driver nuc900_rtc_driver = {
	.remove		= __devexit_p(nuc900_rtc_remove),
	.driver		= {
		.name	= "nuc900-rtc",
		.owner	= THIS_MODULE,
	},
};

static int __init nuc900_rtc_init(void)
{
	return platform_driver_probe(&nuc900_rtc_driver, nuc900_rtc_probe);
}

static void __exit nuc900_rtc_exit(void)
{
	platform_driver_unregister(&nuc900_rtc_driver);
}

module_init(nuc900_rtc_init);
module_exit(nuc900_rtc_exit);

MODULE_AUTHOR("Wan ZongShun <[email protected]>");
MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:nuc900-rtc");
Commit	Line	Data
afd49a7e WZ	1	/*
	2	* Copyright (c) 2008-2009 Nuvoton technology corporation.
	3	*
	4	* Wan ZongShun <[email protected]>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation;version 2 of the License.
	9	*
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/init.h>
	14	#include <linux/platform_device.h>
5a0e3ad6	15	#include <linux/slab.h>
afd49a7e WZ	16	#include <linux/rtc.h>
	17	#include <linux/delay.h>
	18	#include <linux/io.h>
	19	#include <linux/bcd.h>
	20
	21	/* RTC Control Registers */
	22	#define REG_RTC_INIR 0x00
	23	#define REG_RTC_AER 0x04
	24	#define REG_RTC_FCR 0x08
	25	#define REG_RTC_TLR 0x0C
	26	#define REG_RTC_CLR 0x10
	27	#define REG_RTC_TSSR 0x14
	28	#define REG_RTC_DWR 0x18
	29	#define REG_RTC_TAR 0x1C
	30	#define REG_RTC_CAR 0x20
	31	#define REG_RTC_LIR 0x24
	32	#define REG_RTC_RIER 0x28
	33	#define REG_RTC_RIIR 0x2C
	34	#define REG_RTC_TTR 0x30
	35
	36	#define RTCSET 0x01
	37	#define AERRWENB 0x10000
	38	#define INIRRESET 0xa5eb1357
	39	#define AERPOWERON 0xA965
	40	#define AERPOWEROFF 0x0000
	41	#define LEAPYEAR 0x0001
	42	#define TICKENB 0x80
	43	#define TICKINTENB 0x0002
	44	#define ALARMINTENB 0x0001
	45	#define MODE24 0x0001
	46
	47	struct nuc900_rtc {
	48	int irq_num;
	49	void __iomem *rtc_reg;
	50	struct rtc_device *rtcdev;
	51	};
	52
	53	struct nuc900_bcd_time {
	54	int bcd_sec;
	55	int bcd_min;
	56	int bcd_hour;
	57	int bcd_mday;
	58	int bcd_mon;
	59	int bcd_year;
	60	};
	61
	62	static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
	63	{
	64	struct nuc900_rtc *rtc = _rtc;
	65	unsigned long events = 0, rtc_irq;
	66
	67	rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
	68
	69	if (rtc_irq & ALARMINTENB) {
	70	rtc_irq &= ~ALARMINTENB;
	71	__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
	72	events \|= RTC_AF \| RTC_IRQF;
	73	}
	74
	75	if (rtc_irq & TICKINTENB) {
	76	rtc_irq &= ~TICKINTENB;
	77	__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
	78	events \|= RTC_UF \| RTC_IRQF;
	79	}
80
81	rtc_update_irq(rtc->rtcdev, 1, events);
82
83	return IRQ_HANDLED;
84	}
85
86	static int check_rtc_access_enable(struct nuc900_rtc nuc900_rtc)
87	{
2f11e57d	88	unsigned int timeout = 0x1000;
afd49a7e WZ	89	__raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
	90
	91	mdelay(10);
	92
	93	__raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
	94
0a89b553 WZ	95	while (!(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
	96	&& timeout--)
	97	mdelay(1);
afd49a7e	98
0a89b553 WZ	99	if (!timeout)
0a89b553 WZ	100	return ERR_PTR(-EPERM);
afd49a7e	101
0a89b553	102	return 0;
afd49a7e WZ	103	}
afd49a7e WZ	104
84f20a69	105	static int nuc900_rtc_bcd2bin(unsigned int timereg,
afd49a7e WZ	106	unsigned int calreg, struct rtc_time *tm)
	107	{
	108	tm->tm_mday = bcd2bin(calreg >> 0);
	109	tm->tm_mon = bcd2bin(calreg >> 8);
	110	tm->tm_year = bcd2bin(calreg >> 16) + 100;
	111
	112	tm->tm_sec = bcd2bin(timereg >> 0);
	113	tm->tm_min = bcd2bin(timereg >> 8);
	114	tm->tm_hour = bcd2bin(timereg >> 16);
	115
84f20a69	116	return rtc_valid_tm(tm);
afd49a7e WZ	117	}
afd49a7e WZ	118
70d2a0ba	119	static void nuc900_rtc_bin2bcd(struct device dev, struct rtc_time settm,
afd49a7e WZ	120	struct nuc900_bcd_time *gettm)
	121	{
	122	gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
	123	gettm->bcd_mon = bin2bcd(settm->tm_mon) << 8;
70d2a0ba WZ	124
	125	if (settm->tm_year < 100) {
	126	dev_warn(dev, "The year will be between 1970-1999, right?\n");
	127	gettm->bcd_year = bin2bcd(settm->tm_year) << 16;
	128	} else {
	129	gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
	130	}
afd49a7e WZ	131
	132	gettm->bcd_sec = bin2bcd(settm->tm_sec) << 0;
	133	gettm->bcd_min = bin2bcd(settm->tm_min) << 8;
	134	gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
	135	}
	136
afd49a7e WZ	137	static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
	138	{
	139	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	140
	141	if (enabled)
	142	__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)\|
	143	(ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
	144	else
	145	__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
	146	(~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
	147
	148	return 0;
	149	}
	150
	151	static int nuc900_rtc_read_time(struct device dev, struct rtc_time tm)
	152	{
	153	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	154	unsigned int timeval, clrval;
	155
	156	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
	157	clrval = __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
	158
84f20a69	159	return nuc900_rtc_bcd2bin(timeval, clrval, tm);
afd49a7e WZ	160	}
	161
	162	static int nuc900_rtc_set_time(struct device dev, struct rtc_time tm)
	163	{
	164	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	165	struct nuc900_bcd_time gettm;
	166	unsigned long val;
	167	int *err;
	168
70d2a0ba	169	nuc900_rtc_bin2bcd(dev, tm, &gettm);
afd49a7e WZ	170
	171	err = check_rtc_access_enable(rtc);
	172	if (IS_ERR(err))
	173	return PTR_ERR(err);
	174
	175	val = gettm.bcd_mday \| gettm.bcd_mon \| gettm.bcd_year;
	176	__raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
	177
	178	val = gettm.bcd_sec \| gettm.bcd_min \| gettm.bcd_hour;
	179	__raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
	180
	181	return 0;
	182	}
	183
	184	static int nuc900_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	185	{
	186	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	187	unsigned int timeval, carval;
	188
	189	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
	190	carval = __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
	191
84f20a69	192	return nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
afd49a7e WZ	193	}
	194
	195	static int nuc900_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	196	{
	197	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
	198	struct nuc900_bcd_time tm;
	199	unsigned long val;
	200	int *err;
	201
70d2a0ba	202	nuc900_rtc_bin2bcd(dev, &alrm->time, &tm);
afd49a7e WZ	203
	204	err = check_rtc_access_enable(rtc);
	205	if (IS_ERR(err))
	206	return PTR_ERR(err);
	207
	208	val = tm.bcd_mday \| tm.bcd_mon \| tm.bcd_year;
	209	__raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
	210
	211	val = tm.bcd_sec \| tm.bcd_min \| tm.bcd_hour;
	212	__raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
	213
	214	return 0;
	215	}
	216
	217	static struct rtc_class_ops nuc900_rtc_ops = {
	218	.read_time = nuc900_rtc_read_time,
	219	.set_time = nuc900_rtc_set_time,
	220	.read_alarm = nuc900_rtc_read_alarm,
	221	.set_alarm = nuc900_rtc_set_alarm,
	222	.alarm_irq_enable = nuc900_alarm_irq_enable,
afd49a7e WZ	223	};
	224
	225	static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
	226	{
	227	struct resource *res;
	228	struct nuc900_rtc *nuc900_rtc;
	229	int err = 0;
	230
	231	nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
	232	if (!nuc900_rtc) {
	233	dev_err(&pdev->dev, "kzalloc nuc900_rtc failed\n");
	234	return -ENOMEM;
	235	}
	236	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	237	if (!res) {
	238	dev_err(&pdev->dev, "platform_get_resource failed\n");
	239	err = -ENXIO;
	240	goto fail1;
	241	}
	242
	243	if (!request_mem_region(res->start, resource_size(res),
	244	pdev->name)) {
	245	dev_err(&pdev->dev, "request_mem_region failed\n");
	246	err = -EBUSY;
	247	goto fail1;
	248	}
	249
	250	nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
	251	if (!nuc900_rtc->rtc_reg) {
	252	dev_err(&pdev->dev, "ioremap rtc_reg failed\n");
	253	err = -ENOMEM;
	254	goto fail2;
	255	}
	256
23e53be9	257	platform_set_drvdata(pdev, nuc900_rtc);
afd49a7e WZ	258
	259	nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
	260	&nuc900_rtc_ops, THIS_MODULE);
	261	if (IS_ERR(nuc900_rtc->rtcdev)) {
426d3107	262	dev_err(&pdev->dev, "rtc device register failed\n");
afd49a7e	263	err = PTR_ERR(nuc900_rtc->rtcdev);
23e53be9	264	goto fail3;
afd49a7e WZ	265	}
afd49a7e WZ	266
afd49a7e WZ	267	__raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) \| MODE24,
	268	nuc900_rtc->rtc_reg + REG_RTC_TSSR);
	269
23e53be9 WZ	270	nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
23e53be9 WZ	271	if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
2f6e5f94	272	0, "nuc900rtc", nuc900_rtc)) {
23e53be9 WZ	273	dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
	274	err = -EBUSY;
	275	goto fail4;
	276	}
	277
afd49a7e WZ	278	return 0;
afd49a7e WZ	279
23e53be9	280	fail4: rtc_device_unregister(nuc900_rtc->rtcdev);
afd49a7e WZ	281	fail3: iounmap(nuc900_rtc->rtc_reg);
	282	fail2: release_mem_region(res->start, resource_size(res));
	283	fail1: kfree(nuc900_rtc);
	284	return err;
	285	}
	286
	287	static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
	288	{
	289	struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
	290	struct resource *res;
	291
afd49a7e	292	free_irq(nuc900_rtc->irq_num, nuc900_rtc);
23e53be9	293	rtc_device_unregister(nuc900_rtc->rtcdev);
afd49a7e WZ	294	iounmap(nuc900_rtc->rtc_reg);
	295
	296	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	297	release_mem_region(res->start, resource_size(res));
	298
	299	kfree(nuc900_rtc);
	300
	301	platform_set_drvdata(pdev, NULL);
	302
	303	return 0;
	304	}
	305
	306	static struct platform_driver nuc900_rtc_driver = {
	307	.remove = __devexit_p(nuc900_rtc_remove),
	308	.driver = {
	309	.name = "nuc900-rtc",
	310	.owner = THIS_MODULE,
	311	},
	312	};
	313
	314	static int __init nuc900_rtc_init(void)
	315	{
	316	return platform_driver_probe(&nuc900_rtc_driver, nuc900_rtc_probe);
	317	}
	318
	319	static void __exit nuc900_rtc_exit(void)
	320	{
	321	platform_driver_unregister(&nuc900_rtc_driver);
	322	}
	323
	324	module_init(nuc900_rtc_init);
	325	module_exit(nuc900_rtc_exit);
	326
	327	MODULE_AUTHOR("Wan ZongShun <[email protected]>");
	328	MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
	329	MODULE_LICENSE("GPL");
	330	MODULE_ALIAS("platform:nuc900-rtc");