[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 <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 DECLARE_COMPLETION(at91_rtc_upd_rdy);
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);

	wait_for_completion(&at91_rtc_upd_rdy);

	/* 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_SCCR, AT91_RTC_SECEV);
	at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
	at91_rtc_write_ier(AT91_RTC_SECEV);

	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_mon = alrm->time.tm_mon;
	tm.tm_mday = alrm->time.tm_mday;
	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) {
			complete(&at91_rtc_upd_rdy);
			at91_rtc_write_idr(AT91_RTC_SECEV);
		}
		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);

	/* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy
	 * completion.
	 */
	at91_rtc_write_ier(AT91_RTC_SECEV);

	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",
		.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	50	static DECLARE_COMPLETION(at91_rtc_updated);
2fe121e1	51	static DECLARE_COMPLETION(at91_rtc_upd_rdy);
788b1fc6	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	164
2fe121e1 BB	165	wait_for_completion(&at91_rtc_upd_rdy);
2fe121e1 BB	166
788b1fc6	167	/* Stop Time/Calendar from counting */
d28bdfc5 JCPV	168	cr = at91_rtc_read(AT91_RTC_CR);
d28bdfc5 JCPV	169	at91_rtc_write(AT91_RTC_CR, cr \| AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM);
788b1fc6	170
e304fcd0	171	at91_rtc_write_ier(AT91_RTC_ACKUPD);
e7a8bb12	172	wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
e304fcd0	173	at91_rtc_write_idr(AT91_RTC_ACKUPD);
788b1fc6	174
d28bdfc5	175	at91_rtc_write(AT91_RTC_TIMR,
fe20ba70 AB	176	bin2bcd(tm->tm_sec) << 0
	177	\| bin2bcd(tm->tm_min) << 8
	178	\| bin2bcd(tm->tm_hour) << 16);
788b1fc6	179
d28bdfc5	180	at91_rtc_write(AT91_RTC_CALR,
fe20ba70 AB	181	bin2bcd((tm->tm_year + 1900) / 100) /* century */
	182	\| bin2bcd(tm->tm_year % 100) << 8 /* year */
	183	\| bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
	184	\| bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
	185	\| bin2bcd(tm->tm_mday) << 24);
788b1fc6 AV	186
788b1fc6 AV	187	/* Restart Time/Calendar */
d28bdfc5	188	cr = at91_rtc_read(AT91_RTC_CR);
2fe121e1	189	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_SECEV);
d28bdfc5	190	at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL \| AT91_RTC_UPDTIM));
2fe121e1	191	at91_rtc_write_ier(AT91_RTC_SECEV);
788b1fc6 AV	192
	193	return 0;
	194	}
	195
	196	/*
	197	* Read alarm time and date in RTC
	198	*/
	199	static int at91_rtc_readalarm(struct device dev, struct rtc_wkalrm alrm)
	200	{
	201	struct rtc_time *tm = &alrm->time;
	202
	203	at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
	204	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	205	tm->tm_year = at91_alarm_year - 1900;
	206
e304fcd0	207	alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
a2db8dfc DB	208	? 1 : 0;
a2db8dfc DB	209
6588208c	210	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	211	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
e7a8bb12 AM	212	tm->tm_hour, tm->tm_min, tm->tm_sec);
788b1fc6 AV	213
	214	return 0;
	215	}
	216
	217	/*
	218	* Set alarm time and date in RTC
	219	*/
	220	static int at91_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	221	{
	222	struct rtc_time tm;
	223
	224	at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
	225
	226	at91_alarm_year = tm.tm_year;
	227
eb3c2272 LP	228	tm.tm_mon = alrm->time.tm_mon;
eb3c2272 LP	229	tm.tm_mday = alrm->time.tm_mday;
788b1fc6 AV	230	tm.tm_hour = alrm->time.tm_hour;
	231	tm.tm_min = alrm->time.tm_min;
	232	tm.tm_sec = alrm->time.tm_sec;
	233
e304fcd0	234	at91_rtc_write_idr(AT91_RTC_ALARM);
d28bdfc5	235	at91_rtc_write(AT91_RTC_TIMALR,
fe20ba70 AB	236	bin2bcd(tm.tm_sec) << 0
	237	\| bin2bcd(tm.tm_min) << 8
	238	\| bin2bcd(tm.tm_hour) << 16
788b1fc6	239	\| AT91_RTC_HOUREN \| AT91_RTC_MINEN \| AT91_RTC_SECEN);
d28bdfc5	240	at91_rtc_write(AT91_RTC_CALALR,
fe20ba70 AB	241	bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
fe20ba70 AB	242	\| bin2bcd(tm.tm_mday) << 24
788b1fc6 AV	243	\| AT91_RTC_DATEEN \| AT91_RTC_MTHEN);
788b1fc6 AV	244
449321b3	245	if (alrm->enabled) {
d28bdfc5	246	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	247	at91_rtc_write_ier(AT91_RTC_ALARM);
449321b3	248	}
5d4675a8	249
6588208c	250	dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
e7a8bb12 AM	251	at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
e7a8bb12 AM	252	tm.tm_min, tm.tm_sec);
788b1fc6 AV	253
	254	return 0;
	255	}
	256
16380c15 JS	257	static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
16380c15 JS	258	{
6588208c	259	dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
16380c15 JS	260
16380c15 JS	261	if (enabled) {
d28bdfc5	262	at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
e304fcd0	263	at91_rtc_write_ier(AT91_RTC_ALARM);
e24b0bfa	264	} else
e304fcd0	265	at91_rtc_write_idr(AT91_RTC_ALARM);
16380c15 JS	266
	267	return 0;
	268	}
788b1fc6 AV	269	/*
	270	* Provide additional RTC information in /proc/driver/rtc
	271	*/
	272	static int at91_rtc_proc(struct device dev, struct seq_file seq)
	273	{
e304fcd0	274	unsigned long imr = at91_rtc_read_imr();
e24b0bfa	275
e7a8bb12	276	seq_printf(seq, "update_IRQ\t: %s\n",
e24b0bfa	277	(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
e7a8bb12	278	seq_printf(seq, "periodic_IRQ\t: %s\n",
e24b0bfa	279	(imr & AT91_RTC_SECEV) ? "yes" : "no");
788b1fc6 AV	280
	281	return 0;
	282	}
	283
	284	/*
	285	* IRQ handler for the RTC
	286	*/
7d12e780	287	static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
788b1fc6	288	{
e7a8bb12	289	struct platform_device *pdev = dev_id;
788b1fc6 AV	290	struct rtc_device *rtc = platform_get_drvdata(pdev);
	291	unsigned int rtsr;
	292	unsigned long events = 0;
	293
e304fcd0	294	rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
788b1fc6 AV	295	if (rtsr) { /* this interrupt is shared! Is it ours? */
	296	if (rtsr & AT91_RTC_ALARM)
	297	events \|= (RTC_AF \| RTC_IRQF);
2fe121e1 BB	298	if (rtsr & AT91_RTC_SECEV) {
	299	complete(&at91_rtc_upd_rdy);
	300	at91_rtc_write_idr(AT91_RTC_SECEV);
	301	}
788b1fc6 AV	302	if (rtsr & AT91_RTC_ACKUPD)
	303	complete(&at91_rtc_updated);
	304
d28bdfc5	305	at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
788b1fc6	306
ab6a2d70	307	rtc_update_irq(rtc, 1, events);
788b1fc6	308
6588208c	309	dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
788b1fc6 AV	310	events >> 8, events & 0x000000FF);
	311
	312	return IRQ_HANDLED;
	313	}
	314	return IRQ_NONE; /* not handled */
	315	}
	316
de645475 JH	317	static const struct at91_rtc_config at91rm9200_config = {
	318	};
	319
bba00e59 JH	320	static const struct at91_rtc_config at91sam9x5_config = {
	321	.use_shadow_imr = true,
	322	};
	323
de645475 JH	324	#ifdef CONFIG_OF
	325	static const struct of_device_id at91_rtc_dt_ids[] = {
	326	{
	327	.compatible = "atmel,at91rm9200-rtc",
	328	.data = &at91rm9200_config,
bba00e59 JH	329	}, {
	330	.compatible = "atmel,at91sam9x5-rtc",
	331	.data = &at91sam9x5_config,
de645475 JH	332	}, {
	333	/* sentinel */
	334	}
	335	};
	336	MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
	337	#endif
	338
	339	static const struct at91_rtc_config *
	340	at91_rtc_get_config(struct platform_device *pdev)
	341	{
	342	const struct of_device_id *match;
	343
	344	if (pdev->dev.of_node) {
	345	match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
	346	if (!match)
	347	return NULL;
	348	return (const struct at91_rtc_config *)match->data;
	349	}
	350
	351	return &at91rm9200_config;
	352	}
	353
ff8371ac	354	static const struct rtc_class_ops at91_rtc_ops = {
788b1fc6 AV	355	.read_time = at91_rtc_readtime,
	356	.set_time = at91_rtc_settime,
	357	.read_alarm = at91_rtc_readalarm,
	358	.set_alarm = at91_rtc_setalarm,
	359	.proc = at91_rtc_proc,
16380c15	360	.alarm_irq_enable = at91_rtc_alarm_irq_enable,
788b1fc6 AV	361	};
	362
	363	/*
	364	* Initialize and install RTC driver
	365	*/
	366	static int __init at91_rtc_probe(struct platform_device *pdev)
	367	{
	368	struct rtc_device *rtc;
d28bdfc5 JCPV	369	struct resource *regs;
d28bdfc5 JCPV	370	int ret = 0;
788b1fc6	371
de645475 JH	372	at91_rtc_config = at91_rtc_get_config(pdev);
	373	if (!at91_rtc_config)
	374	return -ENODEV;
	375
d28bdfc5 JCPV	376	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	377	if (!regs) {
	378	dev_err(&pdev->dev, "no mmio resource defined\n");
	379	return -ENXIO;
	380	}
	381
	382	irq = platform_get_irq(pdev, 0);
	383	if (irq < 0) {
	384	dev_err(&pdev->dev, "no irq resource defined\n");
	385	return -ENXIO;
	386	}
	387
f3766250 SK	388	at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,
f3766250 SK	389	resource_size(regs));
d28bdfc5 JCPV	390	if (!at91_rtc_regs) {
	391	dev_err(&pdev->dev, "failed to map registers, aborting.\n");
	392	return -ENOMEM;
	393	}
	394
	395	at91_rtc_write(AT91_RTC_CR, 0);
	396	at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
788b1fc6 AV	397
788b1fc6 AV	398	/* Disable all interrupts */
e304fcd0	399	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	400	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	401	AT91_RTC_CALEV);
788b1fc6	402
f3766250	403	ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
dac94d9e	404	IRQF_SHARED,
d728b1e6	405	"at91_rtc", pdev);
788b1fc6	406	if (ret) {
6588208c	407	dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
f3766250	408	return ret;
788b1fc6 AV	409	}
788b1fc6 AV	410
5d4675a8 DB	411	/* cpu init code should really have flagged this device as
	412	* being wake-capable; if it didn't, do that here.
	413	*/
	414	if (!device_can_wakeup(&pdev->dev))
	415	device_init_wakeup(&pdev->dev, 1);
	416
f3766250	417	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
e7a8bb12	418	&at91_rtc_ops, THIS_MODULE);
f3766250 SK	419	if (IS_ERR(rtc))
f3766250 SK	420	return PTR_ERR(rtc);
788b1fc6 AV	421	platform_set_drvdata(pdev, rtc);
788b1fc6 AV	422
2fe121e1 BB	423	/* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy
	424	* completion.
	425	*/
	426	at91_rtc_write_ier(AT91_RTC_SECEV);
	427
6588208c	428	dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
788b1fc6 AV	429	return 0;
	430	}
	431
	432	/*
	433	* Disable and remove the RTC driver
	434	*/
5d4675a8	435	static int __exit at91_rtc_remove(struct platform_device *pdev)
788b1fc6	436	{
788b1fc6	437	/* Disable all interrupts */
e304fcd0	438	at91_rtc_write_idr(AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
e7a8bb12 AM	439	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
e7a8bb12 AM	440	AT91_RTC_CALEV);
788b1fc6 AV	441
	442	return 0;
	443	}
	444
51a0d036 JH	445	static void at91_rtc_shutdown(struct platform_device *pdev)
	446	{
	447	/* Disable all interrupts */
	448	at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD \| AT91_RTC_ALARM \|
	449	AT91_RTC_SECEV \| AT91_RTC_TIMEV \|
	450	AT91_RTC_CALEV);
	451	}
	452
6975a9c1	453	#ifdef CONFIG_PM_SLEEP
788b1fc6 AV	454
	455	/* AT91RM9200 RTC Power management control */
	456
e24b0bfa	457	static u32 at91_rtc_imr;
788b1fc6	458
dac94d9e	459	static int at91_rtc_suspend(struct device *dev)
788b1fc6	460	{
90b4d648 DB	461	/* this IRQ is shared with DBGU and other hardware which isn't
	462	* necessarily doing PM like we are...
	463	*/
e304fcd0	464	at91_rtc_imr = at91_rtc_read_imr()
e24b0bfa JH	465	& (AT91_RTC_ALARM\|AT91_RTC_SECEV);
	466	if (at91_rtc_imr) {
	467	if (device_may_wakeup(dev))
d28bdfc5	468	enable_irq_wake(irq);
e24b0bfa	469	else
e304fcd0	470	at91_rtc_write_idr(at91_rtc_imr);
e24b0bfa	471	}
788b1fc6 AV	472	return 0;
	473	}
	474
dac94d9e	475	static int at91_rtc_resume(struct device *dev)
788b1fc6	476	{
e24b0bfa JH	477	if (at91_rtc_imr) {
e24b0bfa JH	478	if (device_may_wakeup(dev))
d28bdfc5	479	disable_irq_wake(irq);
e24b0bfa	480	else
e304fcd0	481	at91_rtc_write_ier(at91_rtc_imr);
90b4d648	482	}
788b1fc6 AV	483	return 0;
788b1fc6 AV	484	}
788b1fc6 AV	485	#endif
788b1fc6 AV	486
6975a9c1 JH	487	static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
6975a9c1 JH	488
788b1fc6	489	static struct platform_driver at91_rtc_driver = {
5d4675a8	490	.remove = __exit_p(at91_rtc_remove),
51a0d036	491	.shutdown = at91_rtc_shutdown,
788b1fc6 AV	492	.driver = {
788b1fc6 AV	493	.name = "at91_rtc",
6975a9c1	494	.pm = &at91_rtc_pm_ops,
7c1b68d4	495	.of_match_table = of_match_ptr(at91_rtc_dt_ids),
788b1fc6 AV	496	},
	497	};
	498
ac36960f	499	module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);
788b1fc6 AV	500
	501	MODULE_AUTHOR("Rick Bronson");
	502	MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
	503	MODULE_LICENSE("GPL");
ad28a07b	504	MODULE_ALIAS("platform:at91_rtc");