[mirror_ubuntu-artful-kernel.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 <linux/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 = {
};

static const struct at91_rtc_config at91sam9x5_config = {
	.use_shadow_imr	= true,
};

#ifdef CONFIG_OF
static const struct of_device_id at91_rtc_dt_ids[] = {
	{
		.compatible = "atmel,at91rm9200-rtc",
		.data = &at91rm9200_config,
	}, {
		.compatible = "atmel,at91sam9x5-rtc",
		.data = &at91sam9x5_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 = devm_ioremap(&pdev->dev, 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 = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
				IRQF_SHARED,
				"at91_rtc", pdev);
	if (ret) {
		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
		return ret;
	}

	/* 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 = devm_rtc_device_register(&pdev->dev, pdev->name,
				&at91_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);
	platform_set_drvdata(pdev, rtc);

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

/*
 * Disable and remove the RTC driver
 */
static int __exit at91_rtc_remove(struct platform_device *pdev)
{
	/* Disable all interrupts */
	at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
					AT91_RTC_SECEV | AT91_RTC_TIMEV |
					AT91_RTC_CALEV);

	return 0;
}

static void at91_rtc_shutdown(struct platform_device *pdev)
{
	/* Disable all interrupts */
	at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
					AT91_RTC_SECEV | AT91_RTC_TIMEV |
					AT91_RTC_CALEV);
}

#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),
	.shutdown	= at91_rtc_shutdown,
	.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>
8ecc0bf4	34	#include <linux/uaccess.h>
fb0d4ec4	35
75984df0	36	#include "rtc-at91rm9200.h"
d73e3cd7	37
d28bdfc5 JCPV	38	#define at91_rtc_read(field) \
	39	__raw_readl(at91_rtc_regs + field)
	40	#define at91_rtc_write(field, val) \
	41	__raw_writel((val), at91_rtc_regs + field)
788b1fc6	42
788b1fc6 AV	43	#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
788b1fc6 AV	44
de645475	45	struct at91_rtc_config {
e9f08bbe	46	bool use_shadow_imr;
de645475 JH	47	};
	48
	49	static const struct at91_rtc_config *at91_rtc_config;
788b1fc6 AV	50	static DECLARE_COMPLETION(at91_rtc_updated);
788b1fc6 AV	51	static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
d28bdfc5 JCPV	52	static void __iomem *at91_rtc_regs;
d28bdfc5 JCPV	53	static int irq;
e9f08bbe JH	54	static DEFINE_SPINLOCK(at91_rtc_lock);
e9f08bbe JH	55	static u32 at91_rtc_shadow_imr;
788b1fc6	56
e304fcd0 JH	57	static void at91_rtc_write_ier(u32 mask)
e304fcd0 JH	58	{
e9f08bbe JH	59	unsigned long flags;
	60
	61	spin_lock_irqsave(&at91_rtc_lock, flags);
	62	at91_rtc_shadow_imr \|= mask;
e304fcd0	63	at91_rtc_write(AT91_RTC_IER, mask);
e9f08bbe	64	spin_unlock_irqrestore(&at91_rtc_lock, flags);
e304fcd0 JH	65	}
	66
	67	static void at91_rtc_write_idr(u32 mask)
	68	{
e9f08bbe JH	69	unsigned long flags;
	70
	71	spin_lock_irqsave(&at91_rtc_lock, flags);
e304fcd0	72	at91_rtc_write(AT91_RTC_IDR, mask);
e9f08bbe JH	73	/*
	74	* Register read back (of any RTC-register) needed to make sure
	75	* IDR-register write has reached the peripheral before updating
	76	* shadow mask.
	77	*
	78	* Note that there is still a possibility that the mask is updated
	79	* before interrupts have actually been disabled in hardware. The only
	80	* way to be certain would be to poll the IMR-register, which is is
	81	* the very register we are trying to emulate. The register read back
	82	* is a reasonable heuristic.
	83	*/
	84	at91_rtc_read(AT91_RTC_SR);
	85	at91_rtc_shadow_imr &= ~mask;
	86	spin_unlock_irqrestore(&at91_rtc_lock, flags);
e304fcd0 JH	87	}
	88
	89	static u32 at91_rtc_read_imr(void)
	90	{
e9f08bbe JH	91	unsigned long flags;
	92	u32 mask;
	93
	94	if (at91_rtc_config->use_shadow_imr) {
	95	spin_lock_irqsave(&at91_rtc_lock, flags);
	96	mask = at91_rtc_shadow_imr;
	97	spin_unlock_irqrestore(&at91_rtc_lock, flags);
	98	} else {
	99	mask = at91_rtc_read(AT91_RTC_IMR);
	100	}
	101
	102	return mask;
e304fcd0 JH	103	}
e304fcd0 JH	104
788b1fc6 AV	105	/*
	106	* Decode time/date into rtc_time structure
	107	*/
e7a8bb12 AM	108	static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
e7a8bb12 AM	109	struct rtc_time *tm)
788b1fc6 AV	110	{
	111	unsigned int time, date;
	112
	113	/* must read twice in case it changes */
	114	do {
d28bdfc5 JCPV	115	time = at91_rtc_read(timereg);
	116	date = at91_rtc_read(calreg);
	117	} while ((time != at91_rtc_read(timereg)) \|\|
	118	(date != at91_rtc_read(calreg)));
788b1fc6	119
fe20ba70 AB	120	tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
	121	tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
	122	tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
788b1fc6 AV	123
	124	/*
	125	* The Calendar Alarm register does not have a field for
	126	* the year - so these will return an invalid value. When an
25985edc	127	* alarm is set, at91_alarm_year will store the current year.
788b1fc6	128	*/
fe20ba70 AB	129	tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
fe20ba70 AB	130	tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
788b1fc6	131
fe20ba70 AB	132	tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
	133	tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
	134	tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
788b1fc6 AV	135	}
	136
	137	/*
	138	* Read current time and date in RTC
	139	*/
	140	static int at91_rtc_readtime(struct device dev, struct rtc_time tm)
	141	{
	142	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
	143	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	144	tm->tm_year = tm->tm_year - 1900;
	145
6588208c	146	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	147	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	148	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	149
	150	return 0;
	151	}
	152
	153	/*
	154	* Set current time and date in RTC
	155	*/
	156	static int at91_rtc_settime(struct device dev, struct rtc_time tm)
	157	{
	158	unsigned long cr;
	159
6588208c	160	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	161	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	162	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	163
788b1fc6 AV	164	/* Stop Time/Calendar from counting */
d28bdfc5 JCPV	165	cr = at91_rtc_read(AT91_RTC_CR);
d28bdfc5 JCPV	166	at91_rtc_write(AT91_RTC_CR, cr \| AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM);
788b1fc6	167
e304fcd0	168	at91_rtc_write_ier(AT91_RTC_ACKUPD);
e7a8bb12	169	wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
e304fcd0	170	at91_rtc_write_idr(AT91_RTC_ACKUPD);
788b1fc6	171
d28bdfc5	172	at91_rtc_write(AT91_RTC_TIMR,
fe20ba70 AB	173	bin2bcd(tm->tm_sec) << 0
	174	\| bin2bcd(tm->tm_min) << 8
	175	\| bin2bcd(tm->tm_hour) << 16);
788b1fc6	176
d28bdfc5	177	at91_rtc_write(AT91_RTC_CALR,
fe20ba70 AB	178	bin2bcd((tm->tm_year + 1900) / 100) /* century */
	179	\| bin2bcd(tm->tm_year % 100) << 8 /* year */
	180	\| bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
	181	\| bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
	182	\| bin2bcd(tm->tm_mday) << 24);
788b1fc6 AV	183
788b1fc6 AV	184	/* Restart Time/Calendar */
d28bdfc5 JCPV	185	cr = at91_rtc_read(AT91_RTC_CR);
d28bdfc5 JCPV	186	at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM));
788b1fc6 AV	187
	188	return 0;
	189	}
	190
	191	/*
	192	* Read alarm time and date in RTC
	193	*/
	194	static int at91_rtc_readalarm(struct device dev, struct rtc_wkalrm alrm)
	195	{
	196	struct rtc_time *tm = &alrm->time;
	197
	198	at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
	199	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	200	tm->tm_year = at91_alarm_year - 1900;
	201
e304fcd0	202	alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
a2db8dfc DB	203	? 1 : 0;
a2db8dfc DB	204
6588208c	205	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	206	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	207	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	208
	209	return 0;
	210	}
	211
	212	/*
	213	* Set alarm time and date in RTC
	214	*/
	215	static int at91_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	216	{
	217	struct rtc_time tm;
	218
	219	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
	220
	221	at91_alarm_year = tm.tm_year;
	222
	223	tm.tm_hour = alrm->time.tm_hour;
	224	tm.tm_min = alrm->time.tm_min;
	225	tm.tm_sec = alrm->time.tm_sec;
	226
e304fcd0	227	at91_rtc_write_idr(AT91_RTC_ALARM);
d28bdfc5	228	at91_rtc_write(AT91_RTC_TIMALR,
fe20ba70 AB	229	bin2bcd(tm.tm_sec) << 0
	230	\| bin2bcd(tm.tm_min) << 8
	231	\| bin2bcd(tm.tm_hour) << 16
788b1fc6	232	\| AT91_RTC_HOUREN \| AT91_RTC_MINEN \| AT91_RTC_SECEN);
d28bdfc5	233	at91_rtc_write(AT91_RTC_CALALR,
fe20ba70 AB	234	bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
fe20ba70 AB	235	\| bin2bcd(tm.tm_mday) << 24
788b1fc6 AV	236	\| AT91_RTC_DATEEN \| AT91_RTC_MTHEN);
788b1fc6 AV	237
449321b3	238	if (alrm->enabled) {
d28bdfc5	239	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	240	at91_rtc_write_ier(AT91_RTC_ALARM);
449321b3	241	}
5d4675a8	242
6588208c	243	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	244	at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
e7a8bb12 AM	245	tm.tm_min, tm.tm_sec);
788b1fc6 AV	246
	247	return 0;
	248	}
	249
16380c15 JS	250	static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
16380c15 JS	251	{
6588208c	252	dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
16380c15 JS	253
16380c15 JS	254	if (enabled) {
d28bdfc5	255	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	256	at91_rtc_write_ier(AT91_RTC_ALARM);
e24b0bfa	257	} else
e304fcd0	258	at91_rtc_write_idr(AT91_RTC_ALARM);
16380c15 JS	259
	260	return 0;
	261	}
788b1fc6 AV	262	/*
	263	* Provide additional RTC information in /proc/driver/rtc
	264	*/
	265	static int at91_rtc_proc(struct device dev, struct seq_file seq)
	266	{
e304fcd0	267	unsigned long imr = at91_rtc_read_imr();
e24b0bfa	268
e7a8bb12	269	seq_printf(seq, "update_IRQ\t: %s\n",
e24b0bfa	270	(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
e7a8bb12	271	seq_printf(seq, "periodic_IRQ\t: %s\n",
e24b0bfa	272	(imr & AT91_RTC_SECEV) ? "yes" : "no");
788b1fc6 AV	273
	274	return 0;
	275	}
	276
	277	/*
	278	* IRQ handler for the RTC
	279	*/
7d12e780	280	static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
788b1fc6	281	{
e7a8bb12	282	struct platform_device *pdev = dev_id;
788b1fc6 AV	283	struct rtc_device *rtc = platform_get_drvdata(pdev);
	284	unsigned int rtsr;
	285	unsigned long events = 0;
	286
e304fcd0	287	rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
788b1fc6 AV	288	if (rtsr) { /* this interrupt is shared! Is it ours? */
	289	if (rtsr & AT91_RTC_ALARM)
	290	events \|= (RTC_AF \| RTC_IRQF);
	291	if (rtsr & AT91_RTC_SECEV)
	292	events \|= (RTC_UF \| RTC_IRQF);
	293	if (rtsr & AT91_RTC_ACKUPD)
	294	complete(&at91_rtc_updated);
	295
d28bdfc5	296	at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
788b1fc6	297
ab6a2d70	298	rtc_update_irq(rtc, 1, events);
788b1fc6	299
6588208c	300	dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
788b1fc6 AV	301	events >> 8, events & 0x000000FF);
	302
	303	return IRQ_HANDLED;
	304	}
	305	return IRQ_NONE; /* not handled */
	306	}
	307
de645475 JH	308	static const struct at91_rtc_config at91rm9200_config = {
	309	};
	310
bba00e59 JH	311	static const struct at91_rtc_config at91sam9x5_config = {
	312	.use_shadow_imr = true,
	313	};
	314
de645475 JH	315	#ifdef CONFIG_OF
	316	static const struct of_device_id at91_rtc_dt_ids[] = {
	317	{
	318	.compatible = "atmel,at91rm9200-rtc",
	319	.data = &at91rm9200_config,
bba00e59 JH	320	}, {
	321	.compatible = "atmel,at91sam9x5-rtc",
	322	.data = &at91sam9x5_config,
de645475 JH	323	}, {
	324	/* sentinel */
	325	}
	326	};
	327	MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
	328	#endif
	329
	330	static const struct at91_rtc_config *
	331	at91_rtc_get_config(struct platform_device *pdev)
	332	{
	333	const struct of_device_id *match;
	334
	335	if (pdev->dev.of_node) {
	336	match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
	337	if (!match)
	338	return NULL;
	339	return (const struct at91_rtc_config *)match->data;
	340	}
	341
	342	return &at91rm9200_config;
	343	}
	344
ff8371ac	345	static const struct rtc_class_ops at91_rtc_ops = {
788b1fc6 AV	346	.read_time = at91_rtc_readtime,
	347	.set_time = at91_rtc_settime,
	348	.read_alarm = at91_rtc_readalarm,
	349	.set_alarm = at91_rtc_setalarm,
	350	.proc = at91_rtc_proc,
16380c15	351	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
788b1fc6 AV	352	};
	353
	354	/*
	355	* Initialize and install RTC driver
	356	*/
	357	static int __init at91_rtc_probe(struct platform_device *pdev)
	358	{
	359	struct rtc_device *rtc;
d28bdfc5 JCPV	360	struct resource *regs;
d28bdfc5 JCPV	361	int ret = 0;
788b1fc6	362
de645475 JH	363	at91_rtc_config = at91_rtc_get_config(pdev);
	364	if (!at91_rtc_config)
	365	return -ENODEV;
	366
d28bdfc5 JCPV	367	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	368	if (!regs) {
	369	dev_err(&pdev->dev, "no mmio resource defined\n");
	370	return -ENXIO;
	371	}
	372
	373	irq = platform_get_irq(pdev, 0);
	374	if (irq < 0) {
	375	dev_err(&pdev->dev, "no irq resource defined\n");
	376	return -ENXIO;
	377	}
	378
f3766250 SK	379	at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,
f3766250 SK	380	resource_size(regs));
d28bdfc5 JCPV	381	if (!at91_rtc_regs) {
	382	dev_err(&pdev->dev, "failed to map registers, aborting.\n");
	383	return -ENOMEM;
	384	}
	385
	386	at91_rtc_write(AT91_RTC_CR, 0);
	387	at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
788b1fc6 AV	388
788b1fc6 AV	389	/* Disable all interrupts */
e304fcd0	390	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	391	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	392	AT91_RTC_CALEV);
788b1fc6	393
f3766250	394	ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
dac94d9e	395	IRQF_SHARED,
d728b1e6	396	"at91_rtc", pdev);
788b1fc6	397	if (ret) {
6588208c	398	dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
f3766250	399	return ret;
788b1fc6 AV	400	}
788b1fc6 AV	401
5d4675a8 DB	402	/* cpu init code should really have flagged this device as
	403	* being wake-capable; if it didn't, do that here.
	404	*/
	405	if (!device_can_wakeup(&pdev->dev))
	406	device_init_wakeup(&pdev->dev, 1);
	407
f3766250	408	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
e7a8bb12	409	&at91_rtc_ops, THIS_MODULE);
f3766250 SK	410	if (IS_ERR(rtc))
f3766250 SK	411	return PTR_ERR(rtc);
788b1fc6 AV	412	platform_set_drvdata(pdev, rtc);
788b1fc6 AV	413
6588208c	414	dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
788b1fc6 AV	415	return 0;
	416	}
	417
	418	/*
	419	* Disable and remove the RTC driver
	420	*/
5d4675a8	421	static int __exit at91_rtc_remove(struct platform_device *pdev)
788b1fc6	422	{
788b1fc6	423	/* Disable all interrupts */
e304fcd0	424	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	425	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	426	AT91_RTC_CALEV);
788b1fc6 AV	427
	428	return 0;
	429	}
	430
51a0d036 JH	431	static void at91_rtc_shutdown(struct platform_device *pdev)
	432	{
	433	/* Disable all interrupts */
	434	at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
	435	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
	436	AT91_RTC_CALEV);
	437	}
	438
6975a9c1	439	#ifdef CONFIG_PM_SLEEP
788b1fc6 AV	440
	441	/* AT91RM9200 RTC Power management control */
	442
e24b0bfa	443	static u32 at91_rtc_imr;
788b1fc6	444
dac94d9e	445	static int at91_rtc_suspend(struct device *dev)
788b1fc6	446	{
90b4d648 DB	447	/* this IRQ is shared with DBGU and other hardware which isn't
	448	* necessarily doing PM like we are...
	449	*/
e304fcd0	450	at91_rtc_imr = at91_rtc_read_imr()
e24b0bfa JH	451	& (AT91_RTC_ALARM\|AT91_RTC_SECEV);
	452	if (at91_rtc_imr) {
	453	if (device_may_wakeup(dev))
d28bdfc5	454	enable_irq_wake(irq);
e24b0bfa	455	else
e304fcd0	456	at91_rtc_write_idr(at91_rtc_imr);
e24b0bfa	457	}
788b1fc6 AV	458	return 0;
	459	}
	460
dac94d9e	461	static int at91_rtc_resume(struct device *dev)
788b1fc6	462	{
e24b0bfa JH	463	if (at91_rtc_imr) {
e24b0bfa JH	464	if (device_may_wakeup(dev))
d28bdfc5	465	disable_irq_wake(irq);
e24b0bfa	466	else
e304fcd0	467	at91_rtc_write_ier(at91_rtc_imr);
90b4d648	468	}
788b1fc6 AV	469	return 0;
788b1fc6 AV	470	}
788b1fc6 AV	471	#endif
788b1fc6 AV	472
6975a9c1 JH	473	static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
6975a9c1 JH	474
788b1fc6	475	static struct platform_driver at91_rtc_driver = {
5d4675a8	476	.remove = __exit_p(at91_rtc_remove),
51a0d036	477	.shutdown = at91_rtc_shutdown,
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");