[deliverable/linux.git] / drivers / rtc / rtc-at91rm9200.c

/*
 *	Real Time Clock interface for Linux on Atmel AT91RM9200
 *
 *	Copyright (C) 2002 Rick Bronson
 *
 *	Converted to RTC class model by Andrew Victor
 *
 *	Ported to Linux 2.6 by Steven Scholz
 *	Based on s3c2410-rtc.c Simtec Electronics
 *
 *	Based on sa1100-rtc.c by Nils Faerber
 *	Based on rtc.c by Paul Gortmaker
 *
 *	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; either version
 *	2 of the License, or (at your option) any later version.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/ioctl.h>
#include <linux/completion.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <asm/uaccess.h>

#include "rtc-at91rm9200.h"

#define at91_rtc_read(field) \
	__raw_readl(at91_rtc_regs + field)
#define at91_rtc_write(field, val) \
	__raw_writel((val), at91_rtc_regs + field)

#define AT91_RTC_EPOCH		1900UL	/* just like arch/arm/common/rtctime.c */

struct at91_rtc_config {
	bool use_shadow_imr;
};

static const struct at91_rtc_config *at91_rtc_config;
static DECLARE_COMPLETION(at91_rtc_updated);
static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
static void __iomem *at91_rtc_regs;
static int irq;
static DEFINE_SPINLOCK(at91_rtc_lock);
static u32 at91_rtc_shadow_imr;

static void at91_rtc_write_ier(u32 mask)
{
	unsigned long flags;

	spin_lock_irqsave(&at91_rtc_lock, flags);
	at91_rtc_shadow_imr |= mask;
	at91_rtc_write(AT91_RTC_IER, mask);
	spin_unlock_irqrestore(&at91_rtc_lock, flags);
}

static void at91_rtc_write_idr(u32 mask)
{
	unsigned long flags;

	spin_lock_irqsave(&at91_rtc_lock, flags);
	at91_rtc_write(AT91_RTC_IDR, mask);
	/*
	 * Register read back (of any RTC-register) needed to make sure
	 * IDR-register write has reached the peripheral before updating
	 * shadow mask.
	 *
	 * Note that there is still a possibility that the mask is updated
	 * before interrupts have actually been disabled in hardware. The only
	 * way to be certain would be to poll the IMR-register, which is is
	 * the very register we are trying to emulate. The register read back
	 * is a reasonable heuristic.
	 */
	at91_rtc_read(AT91_RTC_SR);
	at91_rtc_shadow_imr &= ~mask;
	spin_unlock_irqrestore(&at91_rtc_lock, flags);
}

static u32 at91_rtc_read_imr(void)
{
	unsigned long flags;
	u32 mask;

	if (at91_rtc_config->use_shadow_imr) {
		spin_lock_irqsave(&at91_rtc_lock, flags);
		mask = at91_rtc_shadow_imr;
		spin_unlock_irqrestore(&at91_rtc_lock, flags);
	} else {
		mask = at91_rtc_read(AT91_RTC_IMR);
	}

	return mask;
}

/*
 * Decode time/date into rtc_time structure
 */
static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
				struct rtc_time *tm)
{
	unsigned int time, date;

	/* must read twice in case it changes */
	do {
		time = at91_rtc_read(timereg);
		date = at91_rtc_read(calreg);
	} while ((time != at91_rtc_read(timereg)) ||
			(date != at91_rtc_read(calreg)));

	tm->tm_sec  = bcd2bin((time & AT91_RTC_SEC) >> 0);
	tm->tm_min  = bcd2bin((time & AT91_RTC_MIN) >> 8);
	tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);

	/*
	 * The Calendar Alarm register does not have a field for
	 * the year - so these will return an invalid value.  When an
	 * alarm is set, at91_alarm_year will store the current year.
	 */
	tm->tm_year  = bcd2bin(date & AT91_RTC_CENT) * 100;	/* century */
	tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8);	/* year */

	tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1;	/* day of the week [0-6], Sunday=0 */
	tm->tm_mon  = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
	tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
}

/*
 * Read current time and date in RTC
 */
static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
{
	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	tm->tm_year = tm->tm_year - 1900;

	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
		1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
		tm->tm_hour, tm->tm_min, tm->tm_sec);

	return 0;
}

/*
 * Set current time and date in RTC
 */
static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
{
	unsigned long cr;

	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
		1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
		tm->tm_hour, tm->tm_min, tm->tm_sec);

	/* Stop Time/Calendar from counting */
	cr = at91_rtc_read(AT91_RTC_CR);
	at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);

	at91_rtc_write_ier(AT91_RTC_ACKUPD);
	wait_for_completion(&at91_rtc_updated);	/* wait for ACKUPD interrupt */
	at91_rtc_write_idr(AT91_RTC_ACKUPD);

	at91_rtc_write(AT91_RTC_TIMR,
			  bin2bcd(tm->tm_sec) << 0
			| bin2bcd(tm->tm_min) << 8
			| bin2bcd(tm->tm_hour) << 16);

	at91_rtc_write(AT91_RTC_CALR,
			  bin2bcd((tm->tm_year + 1900) / 100)	/* century */
			| bin2bcd(tm->tm_year % 100) << 8	/* year */
			| bin2bcd(tm->tm_mon + 1) << 16		/* tm_mon starts at zero */
			| bin2bcd(tm->tm_wday + 1) << 21	/* day of the week [0-6], Sunday=0 */
			| bin2bcd(tm->tm_mday) << 24);

	/* Restart Time/Calendar */
	cr = at91_rtc_read(AT91_RTC_CR);
	at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));

	return 0;
}

/*
 * Read alarm time and date in RTC
 */
static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rtc_time *tm = &alrm->time;

	at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	tm->tm_year = at91_alarm_year - 1900;

	alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
			? 1 : 0;

	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
		1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
		tm->tm_hour, tm->tm_min, tm->tm_sec);

	return 0;
}

/*
 * Set alarm time and date in RTC
 */
static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rtc_time tm;

	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);

	at91_alarm_year = tm.tm_year;

	tm.tm_hour = alrm->time.tm_hour;
	tm.tm_min = alrm->time.tm_min;
	tm.tm_sec = alrm->time.tm_sec;

	at91_rtc_write_idr(AT91_RTC_ALARM);
	at91_rtc_write(AT91_RTC_TIMALR,
		  bin2bcd(tm.tm_sec) << 0
		| bin2bcd(tm.tm_min) << 8
		| bin2bcd(tm.tm_hour) << 16
		| AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
	at91_rtc_write(AT91_RTC_CALALR,
		  bin2bcd(tm.tm_mon + 1) << 16		/* tm_mon starts at zero */
		| bin2bcd(tm.tm_mday) << 24
		| AT91_RTC_DATEEN | AT91_RTC_MTHEN);

	if (alrm->enabled) {
		at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
		at91_rtc_write_ier(AT91_RTC_ALARM);
	}

	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
		at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
		tm.tm_min, tm.tm_sec);

	return 0;
}

static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);

	if (enabled) {
		at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
		at91_rtc_write_ier(AT91_RTC_ALARM);
	} else
		at91_rtc_write_idr(AT91_RTC_ALARM);

	return 0;
}
/*
 * Provide additional RTC information in /proc/driver/rtc
 */
static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
{
	unsigned long imr = at91_rtc_read_imr();

	seq_printf(seq, "update_IRQ\t: %s\n",
			(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
	seq_printf(seq, "periodic_IRQ\t: %s\n",
			(imr & AT91_RTC_SECEV) ? "yes" : "no");

	return 0;
}

/*
 * IRQ handler for the RTC
 */
static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
{
	struct platform_device *pdev = dev_id;
	struct rtc_device *rtc = platform_get_drvdata(pdev);
	unsigned int rtsr;
	unsigned long events = 0;

	rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
	if (rtsr) {		/* this interrupt is shared!  Is it ours? */
		if (rtsr & AT91_RTC_ALARM)
			events |= (RTC_AF | RTC_IRQF);
		if (rtsr & AT91_RTC_SECEV)
			events |= (RTC_UF | RTC_IRQF);
		if (rtsr & AT91_RTC_ACKUPD)
			complete(&at91_rtc_updated);

		at91_rtc_write(AT91_RTC_SCCR, rtsr);	/* clear status reg */

		rtc_update_irq(rtc, 1, events);

		dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
			events >> 8, events & 0x000000FF);

		return IRQ_HANDLED;
	}
	return IRQ_NONE;		/* not handled */
}

static const struct at91_rtc_config at91rm9200_config = {
};

#ifdef CONFIG_OF
static const struct of_device_id at91_rtc_dt_ids[] = {
	{
		.compatible = "atmel,at91rm9200-rtc",
		.data = &at91rm9200_config,
	}, {
		/* sentinel */
	}
};
MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
#endif

static const struct at91_rtc_config *
at91_rtc_get_config(struct platform_device *pdev)
{
	const struct of_device_id *match;

	if (pdev->dev.of_node) {
		match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
		if (!match)
			return NULL;
		return (const struct at91_rtc_config *)match->data;
	}

	return &at91rm9200_config;
}

static const struct rtc_class_ops at91_rtc_ops = {
	.read_time	= at91_rtc_readtime,
	.set_time	= at91_rtc_settime,
	.read_alarm	= at91_rtc_readalarm,
	.set_alarm	= at91_rtc_setalarm,
	.proc		= at91_rtc_proc,
	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
};

/*
 * Initialize and install RTC driver
 */
static int __init at91_rtc_probe(struct platform_device *pdev)
{
	struct rtc_device *rtc;
	struct resource *regs;
	int ret = 0;

	at91_rtc_config = at91_rtc_get_config(pdev);
	if (!at91_rtc_config)
		return -ENODEV;

	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!regs) {
		dev_err(&pdev->dev, "no mmio resource defined\n");
		return -ENXIO;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "no irq resource defined\n");
		return -ENXIO;
	}

	at91_rtc_regs = ioremap(regs->start, resource_size(regs));
	if (!at91_rtc_regs) {
		dev_err(&pdev->dev, "failed to map registers, aborting.\n");
		return -ENOMEM;
	}

	at91_rtc_write(AT91_RTC_CR, 0);
	at91_rtc_write(AT91_RTC_MR, 0);		/* 24 hour mode */

	/* Disable all interrupts */
	at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
					AT91_RTC_SECEV | AT91_RTC_TIMEV |
					AT91_RTC_CALEV);

	ret = request_irq(irq, at91_rtc_interrupt,
				IRQF_SHARED,
				"at91_rtc", pdev);
	if (ret) {
		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
		goto err_unmap;
	}

	/* cpu init code should really have flagged this device as
	 * being wake-capable; if it didn't, do that here.
	 */
	if (!device_can_wakeup(&pdev->dev))
		device_init_wakeup(&pdev->dev, 1);

	rtc = rtc_device_register(pdev->name, &pdev->dev,
				&at91_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc)) {
		ret = PTR_ERR(rtc);
		goto err_free_irq;
	}
	platform_set_drvdata(pdev, rtc);

	dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
	return 0;

err_free_irq:
	free_irq(irq, pdev);
err_unmap:
	iounmap(at91_rtc_regs);

	return ret;
}

/*
 * Disable and remove the RTC driver
 */
static int __exit at91_rtc_remove(struct platform_device *pdev)
{
	struct rtc_device *rtc = platform_get_drvdata(pdev);

	/* Disable all interrupts */
	at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
					AT91_RTC_SECEV | AT91_RTC_TIMEV |
					AT91_RTC_CALEV);
	free_irq(irq, pdev);

	rtc_device_unregister(rtc);
	iounmap(at91_rtc_regs);
	platform_set_drvdata(pdev, NULL);

	return 0;
}

#ifdef CONFIG_PM_SLEEP

/* AT91RM9200 RTC Power management control */

static u32 at91_rtc_imr;

static int at91_rtc_suspend(struct device *dev)
{
	/* this IRQ is shared with DBGU and other hardware which isn't
	 * necessarily doing PM like we are...
	 */
	at91_rtc_imr = at91_rtc_read_imr()
			& (AT91_RTC_ALARM|AT91_RTC_SECEV);
	if (at91_rtc_imr) {
		if (device_may_wakeup(dev))
			enable_irq_wake(irq);
		else
			at91_rtc_write_idr(at91_rtc_imr);
	}
	return 0;
}

static int at91_rtc_resume(struct device *dev)
{
	if (at91_rtc_imr) {
		if (device_may_wakeup(dev))
			disable_irq_wake(irq);
		else
			at91_rtc_write_ier(at91_rtc_imr);
	}
	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);

static struct platform_driver at91_rtc_driver = {
	.remove		= __exit_p(at91_rtc_remove),
	.driver		= {
		.name	= "at91_rtc",
		.owner	= THIS_MODULE,
		.pm	= &at91_rtc_pm_ops,
		.of_match_table = of_match_ptr(at91_rtc_dt_ids),
	},
};

module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);

MODULE_AUTHOR("Rick Bronson");
MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:at91_rtc");
Commit	Line	Data
788b1fc6 AV	1	/*
	2	* Real Time Clock interface for Linux on Atmel AT91RM9200
	3	*
	4	* Copyright (C) 2002 Rick Bronson
	5	*
	6	* Converted to RTC class model by Andrew Victor
	7	*
	8	* Ported to Linux 2.6 by Steven Scholz
	9	* Based on s3c2410-rtc.c Simtec Electronics
	10	*
	11	* Based on sa1100-rtc.c by Nils Faerber
	12	* Based on rtc.c by Paul Gortmaker
	13	*
	14	* This program is free software; you can redistribute it and/or
	15	* modify it under the terms of the GNU General Public License
	16	* as published by the Free Software Foundation; either version
	17	* 2 of the License, or (at your option) any later version.
	18	*
	19	*/
	20
	21	#include <linux/module.h>
	22	#include <linux/kernel.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/time.h>
	25	#include <linux/rtc.h>
	26	#include <linux/bcd.h>
	27	#include <linux/interrupt.h>
e9f08bbe	28	#include <linux/spinlock.h>
788b1fc6 AV	29	#include <linux/ioctl.h>
788b1fc6 AV	30	#include <linux/completion.h>
14070ade	31	#include <linux/io.h>
7c1b68d4 JE	32	#include <linux/of.h>
7c1b68d4 JE	33	#include <linux/of_device.h>
788b1fc6 AV	34
788b1fc6 AV	35	#include <asm/uaccess.h>
fb0d4ec4	36
75984df0	37	#include "rtc-at91rm9200.h"
d73e3cd7	38
d28bdfc5 JCPV	39	#define at91_rtc_read(field) \
	40	__raw_readl(at91_rtc_regs + field)
	41	#define at91_rtc_write(field, val) \
	42	__raw_writel((val), at91_rtc_regs + field)
788b1fc6	43
788b1fc6 AV	44	#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
788b1fc6 AV	45
de645475	46	struct at91_rtc_config {
e9f08bbe	47	bool use_shadow_imr;
de645475 JH	48	};
	49
	50	static const struct at91_rtc_config *at91_rtc_config;
788b1fc6 AV	51	static DECLARE_COMPLETION(at91_rtc_updated);
788b1fc6 AV	52	static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
d28bdfc5 JCPV	53	static void __iomem *at91_rtc_regs;
d28bdfc5 JCPV	54	static int irq;
e9f08bbe JH	55	static DEFINE_SPINLOCK(at91_rtc_lock);
e9f08bbe JH	56	static u32 at91_rtc_shadow_imr;
788b1fc6	57
e304fcd0 JH	58	static void at91_rtc_write_ier(u32 mask)
e304fcd0 JH	59	{
e9f08bbe JH	60	unsigned long flags;
	61
	62	spin_lock_irqsave(&at91_rtc_lock, flags);
	63	at91_rtc_shadow_imr \|= mask;
e304fcd0	64	at91_rtc_write(AT91_RTC_IER, mask);
e9f08bbe	65	spin_unlock_irqrestore(&at91_rtc_lock, flags);
e304fcd0 JH	66	}
	67
	68	static void at91_rtc_write_idr(u32 mask)
	69	{
e9f08bbe JH	70	unsigned long flags;
	71
	72	spin_lock_irqsave(&at91_rtc_lock, flags);
e304fcd0	73	at91_rtc_write(AT91_RTC_IDR, mask);
e9f08bbe JH	74	/*
	75	* Register read back (of any RTC-register) needed to make sure
	76	* IDR-register write has reached the peripheral before updating
	77	* shadow mask.
	78	*
	79	* Note that there is still a possibility that the mask is updated
	80	* before interrupts have actually been disabled in hardware. The only
	81	* way to be certain would be to poll the IMR-register, which is is
	82	* the very register we are trying to emulate. The register read back
	83	* is a reasonable heuristic.
	84	*/
	85	at91_rtc_read(AT91_RTC_SR);
	86	at91_rtc_shadow_imr &= ~mask;
	87	spin_unlock_irqrestore(&at91_rtc_lock, flags);
e304fcd0 JH	88	}
	89
	90	static u32 at91_rtc_read_imr(void)
	91	{
e9f08bbe JH	92	unsigned long flags;
	93	u32 mask;
	94
	95	if (at91_rtc_config->use_shadow_imr) {
	96	spin_lock_irqsave(&at91_rtc_lock, flags);
	97	mask = at91_rtc_shadow_imr;
	98	spin_unlock_irqrestore(&at91_rtc_lock, flags);
	99	} else {
	100	mask = at91_rtc_read(AT91_RTC_IMR);
	101	}
	102
	103	return mask;
e304fcd0 JH	104	}
e304fcd0 JH	105
788b1fc6 AV	106	/*
	107	* Decode time/date into rtc_time structure
	108	*/
e7a8bb12 AM	109	static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
e7a8bb12 AM	110	struct rtc_time *tm)
788b1fc6 AV	111	{
	112	unsigned int time, date;
	113
	114	/* must read twice in case it changes */
	115	do {
d28bdfc5 JCPV	116	time = at91_rtc_read(timereg);
	117	date = at91_rtc_read(calreg);
	118	} while ((time != at91_rtc_read(timereg)) \|\|
	119	(date != at91_rtc_read(calreg)));
788b1fc6	120
fe20ba70 AB	121	tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
	122	tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
	123	tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
788b1fc6 AV	124
	125	/*
	126	* The Calendar Alarm register does not have a field for
	127	* the year - so these will return an invalid value. When an
25985edc	128	* alarm is set, at91_alarm_year will store the current year.
788b1fc6	129	*/
fe20ba70 AB	130	tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
fe20ba70 AB	131	tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
788b1fc6	132
fe20ba70 AB	133	tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
	134	tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
	135	tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
788b1fc6 AV	136	}
	137
	138	/*
	139	* Read current time and date in RTC
	140	*/
	141	static int at91_rtc_readtime(struct device dev, struct rtc_time tm)
	142	{
	143	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
	144	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	145	tm->tm_year = tm->tm_year - 1900;
	146
6588208c	147	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	148	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	149	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	150
	151	return 0;
	152	}
	153
	154	/*
	155	* Set current time and date in RTC
	156	*/
	157	static int at91_rtc_settime(struct device dev, struct rtc_time tm)
	158	{
	159	unsigned long cr;
	160
6588208c	161	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	162	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	163	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	164
788b1fc6 AV	165	/* Stop Time/Calendar from counting */
d28bdfc5 JCPV	166	cr = at91_rtc_read(AT91_RTC_CR);
d28bdfc5 JCPV	167	at91_rtc_write(AT91_RTC_CR, cr \| AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM);
788b1fc6	168
e304fcd0	169	at91_rtc_write_ier(AT91_RTC_ACKUPD);
e7a8bb12	170	wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
e304fcd0	171	at91_rtc_write_idr(AT91_RTC_ACKUPD);
788b1fc6	172
d28bdfc5	173	at91_rtc_write(AT91_RTC_TIMR,
fe20ba70 AB	174	bin2bcd(tm->tm_sec) << 0
	175	\| bin2bcd(tm->tm_min) << 8
	176	\| bin2bcd(tm->tm_hour) << 16);
788b1fc6	177
d28bdfc5	178	at91_rtc_write(AT91_RTC_CALR,
fe20ba70 AB	179	bin2bcd((tm->tm_year + 1900) / 100) /* century */
	180	\| bin2bcd(tm->tm_year % 100) << 8 /* year */
	181	\| bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
	182	\| bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
	183	\| bin2bcd(tm->tm_mday) << 24);
788b1fc6 AV	184
788b1fc6 AV	185	/* Restart Time/Calendar */
d28bdfc5 JCPV	186	cr = at91_rtc_read(AT91_RTC_CR);
d28bdfc5 JCPV	187	at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM));
788b1fc6 AV	188
	189	return 0;
	190	}
	191
	192	/*
	193	* Read alarm time and date in RTC
	194	*/
	195	static int at91_rtc_readalarm(struct device dev, struct rtc_wkalrm alrm)
	196	{
	197	struct rtc_time *tm = &alrm->time;
	198
	199	at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
	200	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	201	tm->tm_year = at91_alarm_year - 1900;
	202
e304fcd0	203	alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
a2db8dfc DB	204	? 1 : 0;
a2db8dfc DB	205
6588208c	206	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	207	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	208	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	209
	210	return 0;
	211	}
	212
	213	/*
	214	* Set alarm time and date in RTC
	215	*/
	216	static int at91_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	217	{
	218	struct rtc_time tm;
	219
	220	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
	221
	222	at91_alarm_year = tm.tm_year;
	223
	224	tm.tm_hour = alrm->time.tm_hour;
	225	tm.tm_min = alrm->time.tm_min;
	226	tm.tm_sec = alrm->time.tm_sec;
	227
e304fcd0	228	at91_rtc_write_idr(AT91_RTC_ALARM);
d28bdfc5	229	at91_rtc_write(AT91_RTC_TIMALR,
fe20ba70 AB	230	bin2bcd(tm.tm_sec) << 0
	231	\| bin2bcd(tm.tm_min) << 8
	232	\| bin2bcd(tm.tm_hour) << 16
788b1fc6	233	\| AT91_RTC_HOUREN \| AT91_RTC_MINEN \| AT91_RTC_SECEN);
d28bdfc5	234	at91_rtc_write(AT91_RTC_CALALR,
fe20ba70 AB	235	bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
fe20ba70 AB	236	\| bin2bcd(tm.tm_mday) << 24
788b1fc6 AV	237	\| AT91_RTC_DATEEN \| AT91_RTC_MTHEN);
788b1fc6 AV	238
449321b3	239	if (alrm->enabled) {
d28bdfc5	240	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	241	at91_rtc_write_ier(AT91_RTC_ALARM);
449321b3	242	}
5d4675a8	243
6588208c	244	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	245	at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
e7a8bb12 AM	246	tm.tm_min, tm.tm_sec);
788b1fc6 AV	247
	248	return 0;
	249	}
	250
16380c15 JS	251	static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
16380c15 JS	252	{
6588208c	253	dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
16380c15 JS	254
16380c15 JS	255	if (enabled) {
d28bdfc5	256	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	257	at91_rtc_write_ier(AT91_RTC_ALARM);
e24b0bfa	258	} else
e304fcd0	259	at91_rtc_write_idr(AT91_RTC_ALARM);
16380c15 JS	260
	261	return 0;
	262	}
788b1fc6 AV	263	/*
	264	* Provide additional RTC information in /proc/driver/rtc
	265	*/
	266	static int at91_rtc_proc(struct device dev, struct seq_file seq)
	267	{
e304fcd0	268	unsigned long imr = at91_rtc_read_imr();
e24b0bfa	269
e7a8bb12	270	seq_printf(seq, "update_IRQ\t: %s\n",
e24b0bfa	271	(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
e7a8bb12	272	seq_printf(seq, "periodic_IRQ\t: %s\n",
e24b0bfa	273	(imr & AT91_RTC_SECEV) ? "yes" : "no");
788b1fc6 AV	274
	275	return 0;
	276	}
	277
	278	/*
	279	* IRQ handler for the RTC
	280	*/
7d12e780	281	static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
788b1fc6	282	{
e7a8bb12	283	struct platform_device *pdev = dev_id;
788b1fc6 AV	284	struct rtc_device *rtc = platform_get_drvdata(pdev);
	285	unsigned int rtsr;
	286	unsigned long events = 0;
	287
e304fcd0	288	rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
788b1fc6 AV	289	if (rtsr) { /* this interrupt is shared! Is it ours? */
	290	if (rtsr & AT91_RTC_ALARM)
	291	events \|= (RTC_AF \| RTC_IRQF);
	292	if (rtsr & AT91_RTC_SECEV)
	293	events \|= (RTC_UF \| RTC_IRQF);
	294	if (rtsr & AT91_RTC_ACKUPD)
	295	complete(&at91_rtc_updated);
	296
d28bdfc5	297	at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
788b1fc6	298
ab6a2d70	299	rtc_update_irq(rtc, 1, events);
788b1fc6	300
6588208c	301	dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
788b1fc6 AV	302	events >> 8, events & 0x000000FF);
	303
	304	return IRQ_HANDLED;
	305	}
	306	return IRQ_NONE; /* not handled */
	307	}
	308
de645475 JH	309	static const struct at91_rtc_config at91rm9200_config = {
	310	};
	311
	312	#ifdef CONFIG_OF
	313	static const struct of_device_id at91_rtc_dt_ids[] = {
	314	{
	315	.compatible = "atmel,at91rm9200-rtc",
	316	.data = &at91rm9200_config,
	317	}, {
	318	/* sentinel */
	319	}
	320	};
	321	MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
	322	#endif
	323
	324	static const struct at91_rtc_config *
	325	at91_rtc_get_config(struct platform_device *pdev)
	326	{
	327	const struct of_device_id *match;
	328
	329	if (pdev->dev.of_node) {
	330	match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
	331	if (!match)
	332	return NULL;
	333	return (const struct at91_rtc_config *)match->data;
	334	}
	335
	336	return &at91rm9200_config;
	337	}
	338
ff8371ac	339	static const struct rtc_class_ops at91_rtc_ops = {
788b1fc6 AV	340	.read_time = at91_rtc_readtime,
	341	.set_time = at91_rtc_settime,
	342	.read_alarm = at91_rtc_readalarm,
	343	.set_alarm = at91_rtc_setalarm,
	344	.proc = at91_rtc_proc,
16380c15	345	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
788b1fc6 AV	346	};
	347
	348	/*
	349	* Initialize and install RTC driver
	350	*/
	351	static int __init at91_rtc_probe(struct platform_device *pdev)
	352	{
	353	struct rtc_device *rtc;
d28bdfc5 JCPV	354	struct resource *regs;
d28bdfc5 JCPV	355	int ret = 0;
788b1fc6	356
de645475 JH	357	at91_rtc_config = at91_rtc_get_config(pdev);
	358	if (!at91_rtc_config)
	359	return -ENODEV;
	360
d28bdfc5 JCPV	361	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	362	if (!regs) {
	363	dev_err(&pdev->dev, "no mmio resource defined\n");
	364	return -ENXIO;
	365	}
	366
	367	irq = platform_get_irq(pdev, 0);
	368	if (irq < 0) {
	369	dev_err(&pdev->dev, "no irq resource defined\n");
	370	return -ENXIO;
	371	}
	372
	373	at91_rtc_regs = ioremap(regs->start, resource_size(regs));
	374	if (!at91_rtc_regs) {
	375	dev_err(&pdev->dev, "failed to map registers, aborting.\n");
	376	return -ENOMEM;
	377	}
	378
	379	at91_rtc_write(AT91_RTC_CR, 0);
	380	at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
788b1fc6 AV	381
788b1fc6 AV	382	/* Disable all interrupts */
e304fcd0	383	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	384	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	385	AT91_RTC_CALEV);
788b1fc6	386
d28bdfc5	387	ret = request_irq(irq, at91_rtc_interrupt,
dac94d9e	388	IRQF_SHARED,
d728b1e6	389	"at91_rtc", pdev);
788b1fc6	390	if (ret) {
6588208c	391	dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
3427de92	392	goto err_unmap;
788b1fc6 AV	393	}
788b1fc6 AV	394
5d4675a8 DB	395	/* cpu init code should really have flagged this device as
	396	* being wake-capable; if it didn't, do that here.
	397	*/
	398	if (!device_can_wakeup(&pdev->dev))
	399	device_init_wakeup(&pdev->dev, 1);
	400
e7a8bb12 AM	401	rtc = rtc_device_register(pdev->name, &pdev->dev,
e7a8bb12 AM	402	&at91_rtc_ops, THIS_MODULE);
788b1fc6	403	if (IS_ERR(rtc)) {
3427de92 JH	404	ret = PTR_ERR(rtc);
3427de92 JH	405	goto err_free_irq;
788b1fc6 AV	406	}
	407	platform_set_drvdata(pdev, rtc);
	408
6588208c	409	dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
788b1fc6	410	return 0;
3427de92 JH	411
	412	err_free_irq:
	413	free_irq(irq, pdev);
	414	err_unmap:
	415	iounmap(at91_rtc_regs);
	416
	417	return ret;
788b1fc6 AV	418	}
	419
	420	/*
	421	* Disable and remove the RTC driver
	422	*/
5d4675a8	423	static int __exit at91_rtc_remove(struct platform_device *pdev)
788b1fc6 AV	424	{
	425	struct rtc_device *rtc = platform_get_drvdata(pdev);
	426
	427	/* Disable all interrupts */
e304fcd0	428	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	429	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	430	AT91_RTC_CALEV);
d28bdfc5	431	free_irq(irq, pdev);
788b1fc6 AV	432
788b1fc6 AV	433	rtc_device_unregister(rtc);
3427de92	434	iounmap(at91_rtc_regs);
788b1fc6 AV	435	platform_set_drvdata(pdev, NULL);
	436
	437	return 0;
	438	}
	439
6975a9c1	440	#ifdef CONFIG_PM_SLEEP
788b1fc6 AV	441
	442	/* AT91RM9200 RTC Power management control */
	443
e24b0bfa	444	static u32 at91_rtc_imr;
788b1fc6	445
dac94d9e	446	static int at91_rtc_suspend(struct device *dev)
788b1fc6	447	{
90b4d648 DB	448	/* this IRQ is shared with DBGU and other hardware which isn't
	449	* necessarily doing PM like we are...
	450	*/
e304fcd0	451	at91_rtc_imr = at91_rtc_read_imr()
e24b0bfa JH	452	& (AT91_RTC_ALARM\|AT91_RTC_SECEV);
	453	if (at91_rtc_imr) {
	454	if (device_may_wakeup(dev))
d28bdfc5	455	enable_irq_wake(irq);
e24b0bfa	456	else
e304fcd0	457	at91_rtc_write_idr(at91_rtc_imr);
e24b0bfa	458	}
788b1fc6 AV	459	return 0;
	460	}
	461
dac94d9e	462	static int at91_rtc_resume(struct device *dev)
788b1fc6	463	{
e24b0bfa JH	464	if (at91_rtc_imr) {
e24b0bfa JH	465	if (device_may_wakeup(dev))
d28bdfc5	466	disable_irq_wake(irq);
e24b0bfa	467	else
e304fcd0	468	at91_rtc_write_ier(at91_rtc_imr);
90b4d648	469	}
788b1fc6 AV	470	return 0;
788b1fc6 AV	471	}
788b1fc6 AV	472	#endif
788b1fc6 AV	473
6975a9c1 JH	474	static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
6975a9c1 JH	475
788b1fc6	476	static struct platform_driver at91_rtc_driver = {
5d4675a8	477	.remove = __exit_p(at91_rtc_remove),
788b1fc6 AV	478	.driver = {
	479	.name = "at91_rtc",
	480	.owner = THIS_MODULE,
6975a9c1	481	.pm = &at91_rtc_pm_ops,
7c1b68d4	482	.of_match_table = of_match_ptr(at91_rtc_dt_ids),
788b1fc6 AV	483	},
	484	};
	485
ac36960f	486	module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);
788b1fc6 AV	487
	488	MODULE_AUTHOR("Rick Bronson");
	489	MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
	490	MODULE_LICENSE("GPL");
ad28a07b	491	MODULE_ALIAS("platform:at91_rtc");